Holographic phase enables quantitative observation of the morphology of bioprinted structures and holds strong potential in bio-fabrication. However, achieving accurate and rapid holographic phase reconstruction for real-time monitoring during 3D bioprinting remains a challenge. In this paper, we propose a novel Global Attention Phase Network (GAP-Net) that focuses on real-time and accurate phase reconstruction for holographic phase monitoring in bioprinting. The GAP-Net leverages lightweight feature extraction module and global attention for semantic segmentation of wrapped phases, enhancing reconstruction precision. In addition, by predicting the first six Zernike coefficients to capture the dominant background aberrations, the method effectively mitigates phase distortions and further improves reconstruction accuracy. The approach achieves real-time phase reconstruction at 22.8 FPS with a 1.11-fold accuracy improvement over existing deep learning methods. The proposed method also enables successful real-time visualization of the curing dynamics of biological samples during bioprinting, further demonstrating its practical effectiveness. This work not only provides real-time observational data for bioprinting but also shows promising potential for broader applications in fields such as optics and biomedical imaging.

Precise motion control of magnetic microrobots in complex and dynamic environments remains a critical challenge for enabling key applications such as targeted therapy and micromanipulation. Purely manual teleoperation is prone to operator fatigue and error, while fully autonomous systems often lack the robustness and adaptability to handle. Here, we propose a human-machine shared cascade control method for magnetically driven microrobots, which effectively integrates human cognitive intelligence with machine autonomy for collision-free navigation in dynamic environments. The outer-loop hybrid shared control unit smoothly modulates control authority in response to real-time collision risk, dynamically integrating the operator instructions and the autonomous navigation system output guided by the enhanced artificial potential field method to formulate the guidance law. For the inner-loop motion tracking, a data-driven adaptive orientation controller is designed, which integrates a nonlinear feedforward compensator leveraging a Gaussian process regression (GPR) model with a linear feedback controller whose parameters are optimized using the virtual reference feedback tuning (VRFT) method, ensuring fast and precise tracking of the desired motion. The effectiveness of the proposed method was validated through both simulation and physical experiments. In human-subject studies conducted on a physical magnetic actuation platform featuring both static and dynamic obstacle scenarios, quantitative results demonstrate that the shared control strategy significantly outperforms both purely manual and fully autonomous modes across all key metrics, including success rate, task completion time, stability, and safety ( $p \lt 0.001$ ). Furthermore, successful navigation within a complex gastric model demonstrates the potential of the shared control system for practical application in unstructured environments.

Magnetic soft millirobotic-grippers, equipped with agile pivot-walking motions and adaptive enveloping morph abilities, hold great promise for biomedical target acquisition tasks. However, deploying these millirobotic-grippers in highly constrained, disturbed, and variable terrains to realize multisequence target acquisition and transport tasks remains challenging. Here, we introduce a hierarchical multimodal motion control method for pivot-walking magnetic milliroboticgrippers, which enhances adaptive locomotion capabilities and enables high-precision motion control, facilitating autonomous target acquisition in complex terrains. The millirobotic-gripper utilizes a centrosymmetric three-pivot design, enabling adaptive soft enveloping deformation and robust multimodal locomotion. A hierarchical control architecture is proposed, comprising: 1) an upper-level Event-Based Finite State Machine planner that dynamically orchestrates transitions between motion modes according to environmental feedback and task-specific conditions; and 2) a lower-level Sliding Mode controller integrated with Gaussian Process-based gait parameter optimization, significantly improving motion accuracy and robustness against environmental disturbances. Experimental results demonstrate that our proposed method allows millirobotic-grippers to efficiently navigate morphing tunnels, leap across gaps exceeding 3 times their body length, accurately follow arbitrary paths with errors less than 5% of their body length, and reliably perform three types of targets grasping and transport. Furthermore, the biomedical application potential of our system is initially validated through ex vivo porcine gastrointestinal tract experiment with ultrasound guidance.

Various forms of biohybrid robots have been developed; however, creating robots with multiple degrees of freedom remains a challenging task. In this paper, we developed a multi-joint biohybrid robot by using skeletal muscle tissue. To achieve this, we first developed a modular bio-actuator actuated by skeletal muscle tissues. The objective of this study was to enhance the contraction force of the actuator and establish optimal experimental conditions for creating high-performance robots. By applying continuous electrical stimulation for five days during culture of bio-actuator, we were able to increase the contraction force by more than threefold. Additionally, we determined the appropriate electric field based on the electrode distance, which enabled us to establish an optimal experimental setup. We also confirmed that connecting the actuators in series can significantly increase the moving distance. Connecting two actuators in series resulted in a total movement distance equivalent to the sum of the distances of each actuator. This finding suggests the potential to create robots with a larger operational workspace. Using these actuators, we first constructed a manipulator with a rotational joint. This research is expected to contribute not only to the development of various robots utilizing bio-actuators but also to advancements in biology technology.

Recent progress in stereo-based 3D Gaussian Splatting (3DGS) SLAM has enabled small-scale robots, which are too small to carry depth cameras, to achieve localization and reconstruct photorealistic scenes with high-speed rendering. However, initializing 3D Gaussians from binocular vision still requires further improvement, and the potential of robot proprioception has not been fully leveraged. This work presents a robust stereo 3DGS SLAM with efficient inertial-legged fusion for small-scale quadruped robots (SaQu-SLAM). We develop a light-weight network to densely initialize the 3D Gaussians in the space. Besides, an efficient fusion method of inertial and legged encoder data based on Kalman filter is introduced. To improve the cross-platform generalization of our algorithm, multiple configuration combinations of these three types of sensors are provided. Moreover, we propose a mode-switching mechanism to handle intermittent visual failures. At last, we perform evaluation on a benchmark dataset, which includes large- and small-scale scenes, and a small quadruped robot in real-world confined-scale scenes, reducing the absolute trajectory error by an average of 19%, 13% and 25% respectively, when compared with other state-of-the-art methods in a similar context. It is also the only successful method in our self-customized confined mixed textured and textureless scene, whereas all vision-based or visual-inertial methods fail. Our system achieves real-time performance even on an embedded platform (Jetson AGX Orin).

For individuals with limited mobility who are bedridden for extended periods, providing comfortable assisted feeding services is one of the most significant actions to enhance their quality of life. Despite the development of various feeding assistive robots, there remain limitations in terms of interaction convenience and safety, which restrict the overall feeding experience for users. To address these challenges, this study first establishes a feeding assistive robot system that integrates multimodal interaction methods. Furthermore, we propose an interactive feeding method that combines both safety and comfort. This method utilizes visual recognition to detect the user’s active meal intent, food selection preferences, and chewing status. Additionally, based on a Large Language Model (LLM), a monitoring thread is designed to conduct voice interactions regarding the user’s ambiguous intentions, temporary changes in intent, emergency situations, and risky behaviors throughout the feeding process. Comprehensive experimental results demonstrate that the proposed multimodal interaction method, which aligns with the natural eating patterns, incorporates both language and visual interactions, the two most convenient forms for users. It also matches force sensing and pose control techniques during the feeding stages, thereby enhancing the flexibility and safety of the assisted feeding system.

Magnetic helical microrobots have great potential in biomedical applications due to their ability to access confined and enclosed environments via remote manipulation by magnetic fields. However, achieving collision-free navigation for microrobots in complex and unstructured environments, particularly in highly dynamic settings, remains a challenge. In this paper, we present a novel deep reinforcement learning-based control framework for magnetic helical microrobots, focusing on the tasks of goal-reaching and dynamic obstacle avoidance. To streamline data collection, a specialized training environment capturing essential aspects of navigation for magnetic helical microrobots is devised. The robustness and adaptability of the trained policy are supported using a randomization technique within the training environment. To facilitate seamless integration with real-world magnetic actuation systems, a visual processing algorithm based on OpenCV is devised and incorporated to collect policy observations. Simulations and experiments in various scenarios validate the high robustness and adaptability of the method. The performance assessment revealed a success rate of 99% in navigating the microrobot around 4 dynamic obstacles of comparable speeds and a success rate of 90% in environments with 14 dynamic obstacles. The results indicate the potential for future applications of our method in unstructured, confined, and dynamic living environments.Note to Practitioners—The motivation of this work is to develop a robust and effective control scheme for collision-free navigation of magnetic helical microrobots in dynamic environments. The conventional navigation strategies in dynamic environments mainly include global path planning and local path replanning; thus, highly dynamic environments require frequent updates to the planned path, making it difficult to apply in highly dynamic environments. In this work, a deep reinforcement learning-based control framework is proposed that can guide microrobots through many dynamic obstacles to a series of locations without collisions. The simulation and experimental results validate the efficacy of the proposed control framework and the robustness and adaptability of the trained policy. The proposed control scheme enables better understanding of advanced motion control methods for magnetic microrobots.

Soft millirobots are highly promising for biomedical applications due to their reconfigurability and multifunctionality within physiological environments. However, the diverse and narrow biological cavity environments pose significant adaptability challenges for these millirobots. Here, we present a dual-morphology, thin-film millirobot equipped with a magnetic drive head and a functional tail to facilitate multimodal motion and targeted cell delivery. The millirobot can reversibly switch between two distinct morphologies in response to environmental stimuli through the deformation of its hydrogel body. Utilizing these dual morphologies, the millirobot can perform robust multimodal fundamental motions controlled by magnetic fields. We encapsulate fundamental motions with specific programmable magnetic field parameters into motion primitives, allowing easy invocation and adjustment of motion modes on demand. A knowledge graph is established to map terrain features to motion units, enabling the identification of optimal motion modes based on typical terrain characteristics. Experimental results indicate that the millirobot can effectively switch its morphology and movement modes to navigate various terrains, including narrow and curved channels as small as 1 mm, 0.8 mm high stairs with a 15° incline, and even the complex environment of a swine intestinal lumen. Its functional tail can carry immune cells to target and kill cancer cells. This robot can transport drugs and cells while navigating complex terrains through multimodal motion, paving the way for targeted medical tasks in intricate human environments in the future.

Tactile information is the research hotspot of wearable flexible sensors due to its importance and complexity. With the innovation of wearable technology and robotics in healthcare, researchers are increasingly integrating wearable flexible sensors on the front end of robots to reproduce the hand tactile manipulation of human tissues. Therefore, it is hoped to develop a thin-film sensor that can be deployed in a small area to assist robots in surgery and data collection of human tissues. Here we use a one-step injection method to fabricate a novel composite sensor based on liquid metal. By laminating multiple PDMS microfluidic layers, the two parameters of pressure and deformation are measured simultaneously in a decoupled manner. The sensor is small and thin, making it easy to integrate into fingers/robot fingers for assistance. The finger/robot finger exerts pressure on the sensor and the sensor deforms with the material to identify the hardness of the material being touched. Separate performance tests of the two sensors show that the strain and pressure functions are decoupled from each other, and their ratios can identify and classify the hardness of different touched materials (glass, PDMS and silicone). This novel composite sensor we proposed can assist robots in manipulating human tissues during medical surgeries. At the same time, its function in tactile information feedback also has broad applications in medical treatment, rehabilitation and services.

Microrobotic contact manipulation enables automated and precise cell capture, positioning and screening and has potential in biomedical engineering and disease detection. However, when using an optical microscope for visual positioning of targets, the poor clarity, limited cell-background contrast and lack of global 3D information of the cells in the field of view hinder global strategy making and automation, thereby affecting the accuracy and efficiency of manipulation. Here, we propose the 3D locating of multiple biological targets based on digital holography. Global–local combined visual feedback is developed for overall spatial locating and partial locating in a liquid-phase bright-field environment. By applying a filtering-based planar locating algorithm and maximum-area-based depth detection algorithm, the 3D global distribution of micro-targets in the field of view is periodically updated with a high detection rate. By applying a planar locating algorithm based on a convolutional neural network and a depth detection algorithm based on a gradient descent, the 3D fast locating of targets is performed precisely. Experiments show that the detection rate of the global positioning is 95.1%, the mean average precision of the local planar positioning is 90.53%, and the deviation of the local depth positioning is$1.22~\mu \text{m}$. When capturing cells, this method reaches an average speed of 7.4 cells/min and a collection rate of 90.5%. We anticipate that our method will support the research in cell-based bioengineering including cell screening and early disease diagnosis. Note to Practitioners—Automated cell manipulation is one of the most significant techniques in cell-based biomedical applications. This paper introduces a three-dimensional multi-target visual positioning method for automated cell manipulation. Combining with holographic imaging technique, the global information for the cells in the limited field of view is provided with improved imaging clarity and extended depth of field. The visual recognition algorithm can screen and extract the rare cells in the cell population, which will support the research in the field of early disease diagnosis and biomedicine. The research outcome provides an effective and precise solution to achieve biological targets positioning, capture, and screening within 3D liquid-phase bright-field environment.

Magnetic helical microrobots have attracted considerable attention in navigation control. However, the performance of microrobots is negatively affected by time-varying uncertain perturbations and obstacles, at the microscale. In this study, we present a navigation control scheme for accurately guiding the helical microrobot to targeted positions in dynamically changing environments. To efficiently plan smooth paths, a search-based algorithm with pruning rules is implemented to quickly find collision-free waypoints and design an optimal method with spatial and dynamic constraints for obtaining smooth paths globally. Velocity gain and potential fields are integrated to develop an emergency local motion replanning method for addressing random obstacles that suddenly appear in the preset path. In order to attain microrobot system dynamic linearization and achieve precise path following of a helical microrobot, a robust control strategy that integrates geometric and model-free controllers in a complementary manner is presented. The geometric controller as a feedforward controller, responsible for managing path information and generating guidance laws. In contrast, the model-free controller operates as a feedback controller, specifically designed to rapidly address position deviation. Meanwhile, we employ an observer to compensate for disturbances. Experimental results of precise motion control in both static and dynamic environments demonstrate the effectiveness of this navigation control scheme, which is promising for moving with high accuracy in cluttered and dynamic living enclosed environments.Note to Practitioners—This paper was motivated by the problem of the navigation control of magnetic microrobots in dynamic environment. The existing navigation control methods of microrobots mainly focus on the static environment, which is challenging to meet the emergency obstacle avoidance requirements in the cluttered environment with low Reynolds number. In addition, the conventional path following control always ignores the nonlinearity of the microrobot system, resulting in insufficient following accuracy. In this work, a novel navigation control method for microrobots is proposed, which can guide microrobots to accurately follow dynamically planned paths in cluttered environments without collision. Simulations and experiments validate the performance of the proposed navigation control method using helical microrobots. The proposed navigation control method paves the way for a better understanding of advanced navigation control method for magnetic microrobots.

Manipulating heterogeneous microtargets based on optoelectronic tweezers (OETs) to construct micropatterns with specific distribution and ordered arrangement enables recapitulating the spatial architecture of cells in native tissues, and has significant potential in tissue regeneration, medical diagnostics, and cell behavior research. However, the uncertain disturbances in liquid environment, collision risk, and electrokinetic interference in OETs system can cause microtargets to deviate from the safe and controlled state, especially for manipulation tasks with heterogeneous microtargets. Here, we propose an improved hierarchical value iteration network (IHVIN)-GAT-based path planning method for parallel manipulation of heterogeneous microtargets with independent control, integrating goal assignment, feature extraction, and decentralized decision-making. The Kuhn-Munkres-based goal assignment model periodically modifies the matching relationship between microtargets and goal positions to reduce the task complexity. High-order features involving path planning are extracted by an IHVIN model, and then selectively aggregated and convolved through GAT to yield real-time locomotion strategies for all microtargets. For the issues of constraint variability and system heterogeneity, discrete locomotion constraints are developed through analysis of escape mechanism, then embedded into modeling procedures and converted to heterogeneous edge weights in graph domain. The simulation and experimental results demonstrate the desired performance of the IHVIN-GAT model in high timeliness, high strategy quality, and compatibility for microtarget number, where up to 20 microtargets from three categories are parallel manipulated within 16 s to form arbitrary micropatterns recapitulating microscale architecture of cells in native tissues. We anticipate that our method will contribute to construct more biomimetic microstructures with heterogeneous cells for biomedical applications in the future.

Micron-range untethered, magnetic helical robots have great potential for biomedical applications due to their desirable performance with high flexibility and accuracy in unstructured and confined environments. However, at the microscale, time-varying uncertain disturbances in the environment and electromagnetic system greatly hinder helical microrobot tracking control performance. When a microrobot is replaced or even a derivative version with a slight helical body structure change is used for different tasks, the performance of the original control scheme remarkably decreases or even becomes ineffective. Here, we propose a data-driven optimal integrated controller (D2-OIC) that realizes precise tracking and transfer control among a series of helical microrobots with derived structures in different situations. The control approach has a parallel structure with nonlinear feedforward and linear feedback controllers. The nonlinear feedforward controller inversely maps the relationship between the electromagnetic field state and the helical microrobot motion state, allowing the helical microrobot to quickly approach the desired motion state. The linear feedback controller effectively adjusts the controller parameters using the virtual reference feedback tuning (VRFT) method, thus eliminating any residual motion errors arising from nonlinear control. By retraining on newly acquired and collected cumulative data with assigned weights, the nonlinear feedforward controller is updated to achieve transfer control among various helical microrobot types. In the experiment, two helical microrobot types performed arbitrary path tracking and obstacle avoidance tasks with tracking errors consistently less than 4% of the microrobot body length, demonstrating the feasibility of the proposed method.

In this paper, we propose a system for real-time rat pose estimation based on stereo vision. The system is dedicated to robot-rat interaction research. First, we design a lightweight, high-resolution network (RRKDNet) for keypoint detection of the rat. The network is trained on a dataset of rat images, which are captured by the robotic rat in first-person view. Second, based on the keypoint detection results, the pose of the rat is obtained by stereo vision model calculation and robot coordinate transformation. At last, we complete a real-time simulation experiment to reproduce the pose of the rat and the robotic rat. The system has been subjected to a series of experiments and the results demonstrate that our network performs better in speed and performance than similar networks. Compared to similar networks, our network has about one-third the number of parameters, while the detection rate increases by 45.25% (the detection rate is 71.57%). The inference speed (34.42 FPS with dual model simultaneous inference) is also faster. The validation error is only 13.85 pixels on the homemade dataset, which is lower than all backbones in Deeplabcut (a toolbox more frequently used for rat keypoint detection). Thus, this work is a significant step in the autonomous intelligent interaction between robots and rats.

In this paper, we fabricated a soft sensor based on PEDOT:PSS for thin film structure. The developed soft sensor can measure the contraction force at real time to be embedded in a modular bio-actuator [1]. The modular actuator generated contraction forces at 0.3 mN when applying electric pulse stimulation. To measure millinewton contraction forces and make a built in sensor, we fabricated a soft sensor using PEDOT:PSS-PDMS film. To verify that the sensor can measure the force of the actuator and can be integrated to the actuator, we analyzed characteristic of the sensor. First, we measure Young's modulus of the sensor and compare them with the bio-actuator. From the previous research [2], the Young's modulus of the bio-actuator and sensor were 45.8 kPa and 165 kPa, respectively. In addition, we simulated the sensors to estimate the change of the displacement according to the applied force. Next, we have experiments by stretching sensors using stepping motor to measure the resistance change of the sensor. From the simulation data, the displacement change is 23 µm when applying 0.3 mN of forces and then we detect the displacement change smaller than is 20 µm from the experiments. Finally, we analyzed the movement of the bio-actuator when applying stimulation using high speed camera and time response of the developed sensor. The actuator was contracted to the maximum after 150 ms from the electrical stimulation and the sensor detected the repeated motion at 10 Hz without time delay. As a result, the proposed sensor can measure the force of bioactuator at real time.

Legged robots are very promising for use in real-world applications, but their operation in narrow spaces is still challenging. One solution for enhancing their environmental adaptability is to design a small-sized biomimetic robot capable of performing multiple motions. By capturing a decent representation of an actual rat (rattus norvegicus), we developed a small-sized quadruped robotic rat (SQuRo), which includes four limbs and one flexible spine. On the basis of the extracted key movement joints, SQuRo was subtly designed with a relatively elongated slim body (aspect ratio: 3.42) and smaller weight (220 g) compared with quadruped robots of the same scale. Accordingly, we propose a control framework for multimodal motion planning, and the appropriate control parameters were tuned through optimization with consideration to the stability and actuation limits. The results obtained through a series of experimental tests reveal that SQuRo achieves a superior motion performance compared with existing state-of-the-art small-sized quadruped robots. Remarkably, SQuRo has an extremely small turning radius (0.48 BL) and strong payload capacity (200 g), and it can recover from falls.

Many previous works have facilitated muscle cell (C2C12) alignment to form fiber-like cell structures. However, there still remains a challenge how to induce C2C12 myoblasts in the cell structures to differentiate into matured myocytes to form a functional muscle tissue, while external mechanical stimulation has been proved to have good effects on proliferation and differentiation of myoblasts. In this paper, we proposed a vision-based micro robotic manipulation system to achieve automatic mechanical stimulation for one single muscle fiber-like cell structures (MFCS). A tube, which is attached to a three degree-of-freedom (DOF) manipulator, and a probe are employed to apply the uniaxial mechanical stimulation to train the MFCS. To measure the force applied on MFCS, a vision-based measuring and correction method is utilized, which decrease the error by 74%. Moreover, based on the viscoelastic property of the MFCS, a feedback control algorithm has been applied to compensate for the force loss to realize the force stimulation. And the final value of force remains 699 ± 1μN after 110s experiment.

In spite of recent high attention of the biohybrid robot system, the previous researches focused on actuation system depend on simple on/off control without feedback control. To solve this problem, we proposed a soft sensor for feedback control of a bio-actuator driven by skeletal muscle. The proposed soft sensor can measure contraction forces of the proposed bio-actuator [1]. The bio-actuator was constructed with tendon structure and culture template made by polydimethylsiloxane (PDMS). It generated contraction forces at 0.3 mN when applying electrical stimulation. To measure that kind of small amount of contraction forces (0.3 mN), we fabricated a soft sensor using liquid metal, Galinstan, and HTV-2000. At first, we measured the Young’s modulus of the bioactuator and sensor and then fabricated the soft sensor having 68.52 kPa of Young’s modulus that is similar the bioactuator (45.8 kPa). Next, we simulated the sensor to estimate the resistance change according to the applied force. Since the resistance change is too small, we design the circuit to amplify the signal. Then, we detect very small resistance at milli-ohm. In addition, we analyzed time response to detect signal of actuator faster than 200 ms. As a result, the proposed sensor can measure the force of bioactuator without time delay.

In this paper, we propose an automatic robot-rat interaction framework that enables a robotic rat to realize real-time localization, tracking and movement analysis of a laboratory rat. Specifically, we combine an object detector with stereo matching to achieve fast localization of the laboratory rat. Combined with the rat-like motion of the robot, one-step tracking of the rat is achieved, which enables the robot to eliminate last location error in one cycle of visual servo control. When positioning the rat, a unified quantitative description and analysis of rat motion is implemented by using a state vector composed of the centroids of head, body and tail. Preliminary robot-rat interaction tests show that the robot achieved a steady tracking of a fast-moving rat for a duration of 10 minutes. To the best of our knowledge, it is the first time that a rat-sized robot achieves a continuous tracking of actual rats by a built-in miniature stereo vision system. Experimental results show that the sequence of state vectors accurately represents the pitch movement of the rat. Thus, this work is a step toward more natural interaction between robots and animals.

For a small-sized biomimetic robot, it is challenging to mimic animal-like motion with high speed and high flexibility. To enable high flexibility, high stability, and high biomimicry degree for the robotic rat, we drew inspirations from three agile rat movements, namely, the pitch, yaw, and U-turn movements. First, we proposed key movement joints (KMJs) to capture a decent representation of the rat with a reduced-order model. By extracting the primary KMJs, we determined the number and distribution of robotic joints for the design of a bioinspired spine mechanism. Second, to meet the demand of high biomimicry degree, we generated an optimal compensation term to minimize the trajectory error introduced by simplifying the model. Moreover, we calculated the optimal minimum motion cycle based on the constraints of equilibrium under extreme conditions to ensure high flexibility without compromising the stability. Finally, the proposed method was successfully verified through simulation and experimental tests with a robotic rat endowed with the bioinspired spine mechanism.

In this paper, we have constructed actively perfusable multiple hepatic lobule-like vascular networks in a 3D cellular structure by using magnetic tweezers. Without well-organized channel networks, cells in a large 3D tissue cannot receive nutrients and oxygen from the channel, and therefore, the cells will be dead after few days. To construct well-organized channel networks, we fabricated a hepatic lobule like vascular networks by using magnetic fields in our previous works. However, the size of the hepatic lobule like vascular network was more than five times larger than real hepatic tissue. To improve the previous research, we have proposed several things. First, we have constructed the vascular network having similar size of the real thing in this step. Second, we have cultured the constructed structure for a long-time (more than two weeks) to verify the biocompatible condition. Third, we assemble the constructed hepatic tissues to make a large size of organ, liver. Finally, an actively perfusable system have been adopted to implement a bioreactor system by adding micro pump.

We propose a novel adsorption pad for wall climbing robot and irregular surface object using capillary force and water sealing. We call this adsorption pad as Super Wet Adsorption pad. The SWA pad has a porous part and a capillary part. The porous part is made by salt reaching method. When the SWA pad adsorbs to the wall which some sand and dust are attached, water comes from the porous part to avoid vacuum breaking. The capillary part is connected to the porous part to supply and stock the water. In this paper, we show the design of the porous part and the capillary part, fabrication process of each parts, and perform the evaluation experiment of the capillary force and adsorption of uneven surfaces, demonstration of wall climbing robot and adsorption of irregular surface foods.

In this paper, we have fabricated a multilayered hepatic lobule-like vascular network in a 3D tissue using a heptapole magnetic tweezer. The tissue consists of cell-laden hydrogels with 3D channel networks. To fabricate multilayered channel system, magnetic hydrogel fibers were manipulated by a magnetic tweezer. The hepatic lobule tissue shows a hexagonal structure with different sizes of veins. Six portal veins transfer the blood including nutrients and oxygen to a central vein by sinusoids. The portal and central veins are made by steel rods, whereas the magnetic hydrogel fibers has a role of sinusoids. An important point of this research is to connect two veins - portal and central vein - by magnetic fibers. For this, we used magnetic tweezer with seven poles to magnetize the steel rods. In order to generate high magnetic fields, we design magnetic tweezer with a flat tip and additional lower tweezer based on simulation data. The manipulation was performed in fibrin gel inside rat liver cells. By applying high magnetic fields, we attracted magnetic fibers to the steel rods and constructed 3D channel network in cellular structure. To verify the efficiency of the channel, we supply culture medium to the channel and then analyze the cell viability according to the distance from the channel. As a result, the cells located at close to the channel show higher cell viability than others.

The research on rare cells makes a significant contribution to biology research and medical treatment for the application of diagnostic operation as well as prognoses treatment. Therefore, sorting them from heterogeneous mixtures is crucial and valuable. Traditional cell sorting methods featured with poor purity and recovery rate as well as limited flexibility, which are not ideal approaches for rare type. In this paper, we proposed a cell screening method based on automated microrobotic aspiration-and-placement strategy under fluorescence microscope. An innovative autofocusing visual feedback (AVF) method is proposed for precise three-dimensional (3D) locating of target cells. For depth detection, multiple depth from defocus (MDFD) method is adopted to solve symmetry problem and attain an average accuracy of 97.07%. For planar locating, Markov random field (MRF) based locating method is utilized to separate and locate the overlapped cells. The end actuator locating and real-time tracking are performed relying on normalized cross-correlation (NCC) method. Experiential results show that our system collects rare cells (100 cells ml-1) at a speed of 5 cells min-1with 90% purity and 75% recovery rate, which is valuable for biological and medical application.

Social interaction between a robot and rats is important since the robot can generate reproducible social behaviors across trials. However, lacking internal state feedback from the rat makes current robot-rat interaction a very preliminary level comparing with rat-rat interaction. Previous biological studies showed that ultrasonic vocalizations (USVs) emitted by a rat are expressions of its internal emotional states, which therefore can be used as part of feedback for a robot-rat interaction. The challenge is to accurately identify rat USVs in real-time from mix sounds generated by the robot in a noisy environment. To address these problems, we propose an SVM-based rat USVs identification method. This SVM method uses three types of features to represents the characteristics of mix sound and use these multidimensional features to identify rat USVs. Results show that our identification method has an accuracy of 84.29% with only 4.84% false-positive rate. Furthermore, we carefully design the filter window length with respect to sound chunk length and use only one microphone to record the mix sound. All of these efforts are to reduce the calculation time to realize real-time identification. Eventually, the identification process can be executed within 3. 5ms, which definitely meet the real-time demand. This research lays the foundation of the feedback based interaction between rat and robot, and also shows promise in the study of ethology and the interaction between robot and animals.

Nanomanipulation system based on scanning electron microscope(SEM) with good real-time visual feedback and nanoscale observation resolution had high operability in a vacuum working environment. Different nanomanipulation tasks of carbon nanotubes (CNTs) are carried out through the nanomanipulation system in SEM. Nanomanipulation platform existed inherent manufacture errors, installation errors and other errors, and imprecise nanomanipulation system were also time-consuming and laborious for operators. This paper presentes a method of combining the visual feedback and feedforward control to detect and compensate the motion error of the multi-dimensional SmarAct nanomanipulation platform in the nanomanipulation system in SEM. This method reduces the motion error in the X-Y direction and achieved higher operating accuracy. At the different step speed, the motion error in the X direction and Y direction is 135.7nm and 112.9nm respectively. After the feedforward compensation, the motion error in the X direction and Y direction reduces to 61.3nm and 54.1nm respectively.

Fabrication of vascular network is an important research for transporting required nutrients and oxygen to the artificial tissues. In this paper, we propose a novel method to construct a hepatic lobule-like vascular network in a 3D cellular structure. The network is simply constructed by three types of veins, central vein, portal vein, and sinusoids. To realize these kinds veins, we utilize two different sizes of steel rods and magnetic fibers for delivering nutrients in 3D cellular structure. Alginate gel fibers embedding ferrite particles are prepared as the same length and are magnetized by magnetizer at 3T. A magnetic tweezer with seven poles is proposed to generate sufficient forces that can manipulate magnetized fibers. Here, two types of rods are magnetized to different magnetic poles in order to attract opposite the end of fibers. This manipulation process is performed in fibrinogen and thrombin solution with liver cells (RLC-18). After solidification of the solution, we deposit solutions with cells and fibers repeatedly, and therefore, a multi-layered structure can be constructed. In addition, we investigate cell a viability in fibrin gel according to the depth of the gel. The result is that the deeper the depth of the gel is, the lower the cell viability is. The cell viability is conducted in several condition. As a result, at the low temperature (here at 22 °C), the viability of cell is increased.

Microgrippers play a significant role in manipulation of micro-objects. To achieve dexterous and precise manipulation, a microgripper is required to be compactly designed and embedded with sensing feedback. Meanwhile, to convert the sensor position into displacement of the microgripper, the embedded sensors should be calibrated by additional equipment like laser sensor. However, a microgripper always needs to be calibrated during manipulation (online calibration), which is still a big challenge with current technology. In this paper, we proposed a highly compact microgripper integrated with position sensors, and a visual-based calibration method to handle such challenge. Moreover, to enhance grasping accuracy, flexure hinges are employed to achieve a low impedance grasping mechanism and to avoid the backlash in traditional bearing. Furthermore, kinematics analysis and Fine Element Analysis (FEA) are implemented to improve the design efficiency. Finally, fibrous micro-rings are successfully assembled, and the results reveal that the calibrated microgripper can be well employed to operate micro-objects.

Study of cellular behaviors, especially the ultra-rare cell type, can aid in the accuracy of clinic diagnoses as well as the development of bioresearch engineering, thus the importance of isolating them from heterogeneous mixtures. However, current methods may fail in purity, versatility or cause contamination to cell targets, which is fatal drawback to rare cells. To address this issue, we propose a versatile method to automatically select and capture fluorescent stained target cells with high purity and recovery rate, through developing a novel 3D image processing algorithm under dark field. With the automated pick-and-place strategies, the micro-robotic system achieves cell screening even in an environment with ultra-sparse cells. In the proposed visual method, Markov Random Field (MRF) separation is adapted into the fluorescent environment to attain real-time planar location of micropipette and target cells. A reformative method derived from Depth from Defocus (DFD) is brought up to acquire 3D information. The basic system for this method mainly consists of a camera mounted on motorized fluorescent microscope and a micromanipulator for cell capture. The fluorescent label help to screen out most of the undesired cells while also bring extra constraints and requisition to our visual method. Finally, experiments of collecting 3 T3 cells are performed to verify the feasibility and validity of the designed method, achieving average 98% purity and 80% recovery rate within the time limits. This study indicates that proposed visual processing method can not only provides reliable location feedback for micro-manipulation in rare cell sorting, but also can be easily extended to satisfy other automated micro-robotics manipulation.

This paper addresses the fault detection and isolation (FDI) problem for robotic assembly of electrical connectors in the framework of set-membership. Both the fault-free and faulty cases of assembly are modeled by different switched linear models with known switching sequences, bounded parameters, and external disturbances. The locations of switching points of each model are assumed to be inside some areas but the accurate positions are not clear. Given current input/output data, the feasible parameter set of fault-free switched linear model is obtained by sequentially calculating an optimal ellipsoid. If the pair of data is not consistent with any possible submodel, a fault is then detected. The isolation of fault is realized by checking the consistency between the data sequence and each possible fault model one by one. The robustness of the proposed FDI algorithms is proved. The effectiveness of these algorithms is verified by the robotic assembly experiments of mating electrical connectors.

Intravascular ultrasound (IVUS) imaging provides two-dimensional (2-D) real-time luminal and transmural cross-sectional images of intravascular vessels with detailed pathological information. It has offered significant advantages in terms of diagnosis and guidance and has been increasingly introduced from coronary interventions into more generalized endovascular surgery. However, IVUS itself does not provide spatial pose information for its generated images, making it difficult to construct a 3-D intravascular visualization. To address this limitation, IVUS imaging-driven 3-D intravascular reconstruction techniques have been developed. These techniques enable accurate diagnosis and quantitative measurements of intravascular diseases to facilitate optimal treatment determination. Such reconstruction extends the IVUS imaging modality from pure diagnostic assistance to intraoperative navigation and guidance and supports both therapeutic options and interventional operations. This paper presents a comprehensive survey of technological advances and recent progress on IVUS imaging-based 3-D intravascular reconstruction and its state-of-the-art applications. Limitations of existing technologies and prospects of new technologies are also discussed.

In micromanipulation, lots of methods have been developed to manipulate objects in microscale. However, few of them can be applied in both the transportation and the rotation of the micro objects. In this paper, we present a novel method to realize the non-contact transportation and rotation of the micro objects based on the vibration-induced swirl flow. A piezo actuator is set between the glass needle and a metal rod. The sine wave with controlled frequency and amplitude is input into the piezo actuator to drive the glass needle to move circularly, which is caused by resonance of the actuator and the metal rod. We place the glass needle under water and keep a limited distance to the bottom. The circular vibration of the glass needle can generate a swirl flow and low pressure around it. The low pressure can trap and transport the micro objects vertically to the glass needle, and the swirl flow can rotate the objects continuously. Finally, we realize the trap and rotation of micro object with only one piezo actuator. Experiments of transportation and rotation of microbeads are carried out, and the results demonstrate it is a simple, low-cost, effective micromanipulation method.

This study presents the high-precision microinjection of fluorescent micro-gel beads into Caenorhabditis elegans trapped in a suction microchannel. In our previous works, we demonstrated survival microinjection by a conventional micromanipulation technique. However, the focal planes differed between the tip of the microinjection tool and the target axon inside the C. elegans body. To resolve this problem, we here propose a suction microchannel that traps C. elegans during the microinjection operation. The focal plane of the target nerve axon matches that of the fluorescent microbead in the microinjection tool, enabling high-precision microinjection into the interior of the C. elegans body under a microscopic view. In an experimental evaluation, the positioning accuracy of the injection into C. elegans was within the target accuracy (15 μm). The head-flrst navigation alignment of C. elegans along the microchannel was controlled by electrotaxis. Injection of the fluorescent micro-gel bead into the C. elegans body was quantitatively confirmed by confocal microscopy.

Helical structure assembled by hydrogel microfibers is significant for culture of smooth muscle cells. However, the helical structure is only fabricated at the macroscale, while the fabrication of helical microstructure is still a challenge due to the lack of assembly method. In this paper, we propose a robotics-based assembly method to handle such challenge. An electromagnetic needle (EMN) is employed as end-effector to magnetically reel the microfiber encapsulating magnetic nanoparticles around a micropillar, and a dual-ring structure is designed to keep the microfiber being attracted at the EMN tip. For enhancing the stability of tip attraction, the manipulation mode of anticlockwise pushing microfiber is established. Moreover, the interaction mechanism between EMN tip and microfiber is analyzed by developing a static force model, and then the key condition of stably reeling microfiber is concluded. Furthermore, a robotics-based motion trajectory of EMN tip is planned to achieve a smooth reeling process. Based on such planning, the size of dual-ring structure is further optimized to improve the success rate of reeling. Finally, the helical microstructure with there-turn coils is successfully fabricated.

This paper describes a octo-rotor unmanned aerial vehicle (UAV) with one degree of freedom (DoF) manipulator for bridge inspection. The UAV has an ability to contact bridge pier to conduct hammering test. To control contact force applied by the UAV to the bridge pier, one DoF is enough for the manipulator implemented on the UAV. A preliminary experiment shows that the force is proportional to the pitch angle of the UAV when it contacts the bridge pier. A bridge pier contact experiment shows that our developed UAV can control contact force between its end-effector and the bridge pier; mean error of the contact force is 4.27 ± 3.64 [N] against 20[N] desired force.

In this paper, we introduce a walking load control strategy with a cane-type robot for gait training. The population of elderly people is increasing in most of the developed countries, and there is a growing demand for caregivers. Assistive robots are expected as a solution to provide aid in order to reduce the burden of caregivers in gait training of elderly people. Our research group has been developing a series of cane-type walking assistive robots named Intelligent Cane on admittance control to provide safe and efficient gait training. We propose an adaptive design method of the admittance control model in order to control user's walking load for the purpose of rapid improvement of user's physical strength. In the proposed method, the cane robot automatically adjusts control parameters of an admittance control model based on a correlation between a set of admittance parameters and a user's walking energy consumption. We conducted experiments to evaluate the proposed adaptive control strategy through a convergence error between estimated walking load and target one while walking training. We confirm the advantage of using the cane robot in rehabilitation.

The interaction test between a robotic rat and living rat is considered as a possible way to quantitatively characterize the rat sociality. In such robot-rat interactions, the robot should be designed to fully replicate a real rat in terms of morphological and behavioral characteristics. To address this problem, a multi-jointed robot prototype has been modified based on our previous work. We optimally update the forelimb of the robot and redesign the control board to make it more dexterous and increase its behavioral capability. Then, we systematically and kinematically analyze the rotational range of joint variables and the workspace of the robot by using traversal method. To evaluate the motion capability of the modified robot, we propose two quantitative parameters: maximum reachable height (MRH) and minimum bendable distance (MBD). Additionally, we achieve to quantitatively evaluate the behavioral similarity between the robot and rat with the calculated accumulative distance (AD) by using dynamic time warping (DTW). These evaluated methods show high promise to improve the robot-rat interaction to be more similar to rat-rat interaction.

In this research, we fabricated movable toroidal cell structures inside a microfluidic device for tissue engineering applications. A photo-crosslinkable biodegradable hydrogel gelatin methacrylate (GelMA) was employed to encapsulate biological cells for assembling cell structures. The UV light power and the concentration GelMA hydrogel were optimized to achieve both fabrication of microstructures and live condition of cells. The two-layered toroidal cell structures were fabricated which can mimic the multi-layered structure of blood vessels. The movable microstructures were achieved by the water repellent coating on the substrate surface. Finally, on-chip fabrication of GelMA microstructures and peeling off of the fabricated microstructures were achieved using a microfluidic chip. The results indicate that the fabricated movable GelMA microstructures can be used for further three dimensional assembly to achieve vascular-like tube structures.

Microscopy has been an indispensable tool for micro/nanosample imaging, manipulation, and characterization. However, viewing the micro/nanosample from multidirection is still a big challenge for current microscopy. To address the above issue, this paper proposes a novel nanorobotic manipulation system for the automatic alignment and multidirectional imaging under microscopes. First, a miniature rotation robot with three degrees of freedom is designed and integrated with a microscope. Then, a forward-backward alignment strategy containing three loops, i.e., position shift loop, angle loop, and magnification loop, is proposed to align the sample to the rotation axis of the robot automatically. After that, the sample is imaged from multidirection by rotating the robot with one revolution (360°). Finally, the alignment accuracy is evaluated and multi-directional images of various samples are implemented. This study provides a new way for the microscopic imaging, which is expected to exert a significant impact in multiple fields on a small scale, including microscopy imaging, microdefect detection, micromanipulation, in situ characterization, and so on.

Conventional humanoids have achieved walking and running by independent controllers, even though a transition between these independent motions should be added to connect them while ensuring stability. In contrast, human selects walking/running at low/high speed in terms of energy efficiency, and transits between them naturally. This fact implies that human gait shares the inherent controller among walking and running despite their quite different appearances. Hence, we propose a “unified bipedal gait,” which includes walking, running, and the transition. The unified bipedal gait has the inherent controller: passive dynamic autonomous control (PDAC) with a damping and spring loaded inverted pendulum (D-SLIP) model. The PDAC constrains the humanoid natural dynamics by a virtual holonomic constraint (VHC) that degenerates the natural manifold of the states for stabilization. Compliance in the D-SLIP is capable to yield the required characteristics of walking/running: low/high compliant legs for walking/running. Thus, a novel VHC is designed to extract the required characteristics of walking/running from the D-SLIP dynamics and form the proper manifold. As a result, we achieved the unified bipedal gait that bifurcates to walking and running via the natural transition. The high energy efficiency was confirmed in this unified bipedal gait at any gait speed.

This paper presents a novel In situ nanomanipulation integrated with scanning electron microscope- computed tomography (SEM-CT) imaging system for 3D nanomanipulation. In our previous works, a nanorobotic manipulation system was established inside an environmental-SEM (E-SEM) for water-contained samples, including biological organism, based on a real-time high resolution SEM observation. However, the SEM image is limited in two dimensional (2D) and surficial information from the signals of secondly electrons. For nanosurgery applications, such as nanoinjection, it is needed to evaluate the sample in 3D space with its internal information after manipulation. The SEM-CT imaging system is developed for In situ nanomanipulation based on SEM observation. The CT is an effective method to obtain the internal 3D information as a non-destructive manner. The imaging resolution of our SEM-CT system is in less than 400 nm. A Caenorhabditis elegans (C. elegans) was used as a target of biological sample. To improve the contrast of SEM-CT imaging of C. elegans, the X-ray was tested by generating using brass and copper materials. Finally, the nanoinjection was demonstrated with SEM-CT imaging system to C. elegans using the nanoinjector which was fabricated by focused ion beam (FIB) process.

It is of great importance to pick up a single carbon nanotube (CNT) from a bulk of CNTs for nanodevice fabrication. In this study, we have proposed a nanorobotic manipulation system allowing automated pick-up of CNTs based on visual feedback. We utilize histogram normalization for automatic binarization, and it achieves to clearly distinguish CNTs from substrate and other impurities under different image brightness. Furthermore, we develop the gradient orientation inversion (GOI) algorithm to recognize CNT tip and atomic force microscopy (AFM) cantilever. Taking full advantages of the geometrical characteristics of CNT and AFM cantilever, GOI is proved to be quite robust. We have designed segment detection method (SDM) to successfully separate the AFM cantilever and CNT, whereas the contact detection between them is achieved by analyzing the straightness variation. Preliminary experimental results imply that our method shows high promise in realistic fabrication of nanodevices.

This paper proposes a quasi-passive dynamic autonomous control (Q-PDAC) for a three-dimensional (3-D) bipedal gait of humanoid robots from start points to goal points. The major approach for 3-D traveling is currently footstep planning by a constantly stable gait with an emphasis on its accurate and secure traveling. However, energy would potentially be wasted when the robot accurately travels according to the planned footsteps. In contrast, a limit-cycle-based gait possesses the good efficiency by a gait speed control, although the accurate and secure traveling is difficult for it. Its gait speed control is unfortunately not enough to freely travel on 3-D spaces: shortages of a turning speed control, trackability of horizontal speed, and stability of the bipedal gait. Hence, the Q-PDAC supplies three proper angular momenta by hip and ankle joints to achieve the turning motion and enhance the trackability of horizontal motion. Three angular momenta are simply designed consistent in the PDAC dynamics, and achieved the sufficient gait speed control for 3-D traveling. As a result, the robot can efficiently travel from the start point to the goal point while following a leader point not to collide with walls.

In this paper, we propose a new method to assemble microstructures with biological cells towards in vitro 3D cellular structures. The proposed assembly method uses self-assembly process of magnetized toroidal microstructures. Biocompatible toroidal hydrogel microstructures are prepared by electrodeposition method, and ferrite particles are put on the fabricated structures using poly-L-lysine (PLL). The microstructures are magnetized by the magnetic field at 3 T, and assembled by the magnetic self-assembly process. Biological cells were encapsulated in the microstructures and cultured to achieve high density of cells inside structures. The magnetized microstructures were assembled automatically. The magnetic force generated from the ferrite embedded microstructures was estimated and compared to the fluid resistance applied to the microstructures. The proposed method can be applied to achieve 3D in vitro cell structures with vascular networks for tissue engineering applications.

This paper describes a magnetic resonance imaging (MRI) compatibility assessment of our lower-extremity motion simulator called LoMS which provides gait-like motion for a wearer within his/her lying posture during functional MRI (fMRI) imaging. We confirmed that the existence and the movement of LoMS do not decrease the fMRI image quality when the distance between LoMS and the head coil of MRI is practical distance (more than 400 mm). We also confirmed that LoMS can operate properly in MRI environment, which is to measure own joint angle avoiding the noise from fMRI imaging. Then we show that the brain activity related to gait motion can be imaged during gait-like motion.

Walking capability composed of stability and efficiency is one of the most important issues in the field of humanoid robots. An effective swing of the arms is expected to enhance the walking capability under the constraints from the limited body. We propose an arm-swing method to enhance the stability and efficiency by selecting optimal arm-swing strategy depending on the walking conditions. In this research, we select the optimal strategy between the support of the center of gravity (COG) tracking for stability and the walk without arm-swing for efficiency. To support the COG tracking, we employ a predictive control. States are defined as an inverted pendulum model and inputs are given as an inertial force of arm-swing. Input and output weights in the predictive control are adjustable by a support weight introduced in this paper. Selection of the optimal support weight by a selection algorithm for locomotion (Su-SAL) switches the two strategies by adjusting the ratio of input and output (I/O) weights. Su-SAL maximizes the efficiency while keeping the stability in comparison with the case of the constant support weight.

Fall prevention is one of the most important functions of walking assistance devices for user's safety. It is preferable that these devices obviates factors which induce falling over rather than helping them recovering from falling motion. Tandem stance, where both legs form a line along walking direction, is a factor of falling. It is often observed in turning motion because a swing leg moves in lateral direction as well as forward. Generally, upper body's turning of a person proceeds before lower limb's turning during walking, and the behavior of the lower limb is constrained by upper body turning. It is thus possible to control behavior of the lower limb for tandem stance prevention by constraining behavior of the upper body. This paper therefore introduces a tandem stance prevention method for safer walk of the elderly or physically challenged person. The method adjusts admittance of cane robot's turning motion according to the positions of a support leg and a swing leg. The cane robot measures user's leg position and estimates a walk phase of the user. By adjusting an admittance model of the cane robot based on the walk phase, the cane robot resists to turn while support leg is on the same side of the turning direction. As a result, the tandem stance is avoided. Through experiments, we confirmed that the cane robot successfully controls user's upper body's behavior to prevent the user from being in tandem stance.

Due to the poor controllability in hydrogels, Hydrogels-based assembly to form larger 3D complex shapes is still a big challenge. In this paper, we have reported a novel “bottom-up” method to fabricate three-dimensional (3D) magnetic alginate microfibers (MAMs) assemblies with complex shapes. Specifically, Alginate microfibers encapsulating Fe3O4magnetic nanoparticles (MNs) and fibroblasts (NIH/3T3) have been spun using microfluidic method with “pinch-off” scheme. Experimental results show that the MAMs can respond quickly to the magnetic field, enabling their enhanced controllability. The magnetic assembly system is constructed by PDMS microfluidic device, 3D supporting model adhered on the bottom surface of dish filled with deionized water and magnet. The microfluidic “printing“ and magnetic deposition in magnetic assembly process are experimentally demonstrated, respectively. Because of magnetic field, the complex assembly shapes can be fabricated just by moving the microfluidic device in a plane. To match well with the shape of supporting model and to keep a stable assembly structure, the secondary cross-linking method is employed. From the LIVE/DEAD assay, cells can survive well during the magnetic assembly process.

In this paper, we conducted a new method to assemble microstructures inside a droplet named “Lab in a Droplet (LiD)”. The method can realize the assembly of micro-nano structures inside a droplet size. The surface tension is used to assemble microstructures automatically. Micro-scale or nano-scale objects are ejected from an inkjet nozzle. They are gathered at the center of the droplet and assembled by the surface tension. We conducted preliminary experiments to check whether the self-assembly of microstructures can be achieved by LiD. The experimental results show that the self-assembly of microbeads is conducted inside a droplet. The nano-scale objects can be patterned on a substrate depend on their sizes. A microstructure made of photo-crosslinkable resin was prepared, and microbeads were assembled with the microstructure inside a droplet. The method can be used for autonomous assembly of micro-nano structures in high precision.

This paper presents a fabrication method of multi-graphene box structure by a nanomanipulation in a Field Emission Scanning Electron Microscope (FESEM). To bend the multi-graphene in plastic deformation region, the bending stress were measured using a silicon cantilever based on the nanomanipulation. In this study, defects were introduced inside the multi-graphene on the folding line of the multi-graphene by irradiating an electron beam assisted with oxygen gas. From experimental bending stress measurement, the bending stress was dropped with electron beam irradiation in oxygen gas environment. The fabrication of 3D box structure of multi-graphene was demonstrated from a cubic net of multi-graphene which was fabricated by a Focused Ion Beam (FIB) etching process. For bending the one side of the cubic net graphene, a tungsten probe was used after reforming by FIB etching as end-effector of nanomanipulator. The multi graphene was bent to form a box structure in 3D space.

In this study, we describe a novel method of fabricating shape-controlled calcium alginate gel microcapsules. Alginate-poly-L-lysine (PLL) hydrogel microcapsules with predefined shapes were constructed based on electrodeposition method. Firstly, electrolysis of water in alginate solutions with calcium carbonate particles induced alginate gelation on micro-patterned electrode to form 2D gel structures. Then, these structures will be detached from the electrode surface and treated with the alginate-PLL microcapsules system. By passive control based on the micro-pattern geometric confinement and electrodeposition parameters, we succeeded in producing calcium alginate-PLL microcapsules with diverse shapes (such as sphere rod and cubic). The shape and size of the calcium alginate microcapsules could be tuned by adjusting the geometric design of micro-pattern on electrode and the apply voltage of electrodepostion. The preparation conditions of size- and shape-controlled calcium alginate-PLL microcapsules and influence factors were studied. This proposed method can lead to more accurate and creative studies of fabricating biocompatibility scaffold for tissue engineering.

Fabrication of artificial blood vessels in micro scale significantly benefits the regeneration of functional human vascular networks. In this paper, we develop an efficient multi-microrobotic system with an innovative motorized sample holder (MSH) and two manipulators. Air is injected into the solution through a glass pipette fixed on one manipulator to create bubbles. These bubbles conduct a regular rising movement, which is utilized to assemble the 2D ring-shaped microgels fabricated in a simple micro fluidic device. With this novel bubble-based method and the robotic system, we achieve the automation of the assembly. A 1.2 mm long vascular-like microtube with an outer diameter of 200 μm is fabricated. The whole process of the bubble-based assembly is visually observed and analyzed with side view. Key parameters are characterized to improve the assembly. Results show that the automated bubble-based assembly success rate is 100% and average time cost of assembling every microgel is as low as 3.25s.

In this study, cell-laden alginate-poly-L-lysine (PLL) hydrogel structures with arbitrary shapes were constructed based on electrodeposition method. Electrolysis of water in alginate solutions with calcium carbonate particles induced alginate gelation on micro-patterned anode electrode, and cell-laden alginate gel structures were formed. The several different shapes of gel were generated at one time by predefined micro-patterns. The micro-patterned electrode was fabricated by coating photoresist on Fluorine-doped tin oxide (FTO) glass slide. Alginate-PLL encapsulation technique was introduced to this platform forming alginate-PLL hydrogel structures. This proposed method can lead to more accurate and creative studies of fabricating cell-laden scaffold for tissue engineering.

This study presents the survival microinjection into Caenorhabditis elegans (C. elegans) with in vivo observation based on micromanipulation. The microinjections were achieved with micro-gel beads which are enable to encapsulate chemicals for injection. In this study, a fluorescent material was used to evaluate the injection positional precision inside the C. elegans. The fluorescent microbead was picked up at the tip of a micropipette injection tool and injected by a piezo actuated microinjector. The distance between the injected micro-gel bead and closest nerve axon was measured as 20.3 μm and 16.5 μm by in vivo observation of a confocal microscopy. The two types of pipette tools were used to evaluate the success and survival rates of microinjection, and the smaller pipette (pipette A, 0.8 μm in diameter) showed higher rates as 50 % and 67 % respectively.

A cane-type robot called intelligent cane has been developed to support the elderly during walking. By supporting a part of a user's body weight, the cane robot aims to reduce a load applied to a user's affected leg. Therefore, while the user's affected leg is a support leg, it is preferable that the cane robot stops to sufficiently support the user. In our previous work, the cane robot is controlled based on horizontal component of force applied to the cane robot and moment around a vertical axis. In this paper, virtual friction force, which is proportional to vertical component of force, is proposed to improve a walking assistance capability of the cane robot. In addition, virtual frictional coefficients are arranged based on the user's state inferred by a laser range finder. By employing the proposed method, the cane robot moves easily in the both legs support phase, stops in the healthy leg support phase, and supports the user reliably in the affected leg support phase.

An environmentally specific type of locomotion (e.g., bipedal or quadrupedal walking) is effective only under the specified environments. However, other conditions could cause physical body constraints and decrease mobility. Despite these constraints, legged robots are desired with high overall mobility such that they can walk under various conditions. Thus, a combination of types of locomotion is needed to maximize overall mobility. We have developed a gorilla-type robot, which can switch between bipedal and quadrupedal walking. A selection technique to optimize locomotion choice would be beneficial to the robot, which will experience challenging situations when walking through complex terrains, receiving disturbances, or malfunctioning. We present a selection algorithm for locomotion (SAL) that improves overall mobility by autonomously selecting the optimal locomotion. The falling risk of each locomotion mode is evaluated with a Bayesian network to represent the robot's situation. The evaluation function for the SAL determines the optimal locomotion choice based on falling risk and moving speed. In this paper, the SAL is used for two state variables of locomotion: gait (Ga-SAL) and speed (Sp-SAL). Both the simulations and experiments validated that the robot traveled efficiently in complex environments.

In the past we achieved to use a rat-like robot and a single rat to develop Animal Models of Mental Disorder (AMMDs) through stress exposure. However, to simulate the real social environment, we use a rat-like robot composed of multiple links to chase a specific rat (target) in a group of rats (outside observers). In this paper, we aim to develop a real-time control system for a multi-link robot surrounded by multiple rats. A virtual impedance model was adopted to generate posture and trajectory for a multi-link robot named WR-5. With the analysis of virtual forces/moments acting on WR-5 based on the model, corresponding dynamic equations can be obtained to control the motion of WR-5. Simulation results show that the head of WR-5 can accurately direct a target object in the following test. After conducting experiments with three rat subjects (a target rat, two outside observers), the output results suggest that the head and body gesture of WR-5 achieves to follow the target in real-time. Meanwhile, the control system allows real-time avoidance of the moving outside observers during interaction.

3D assembly of cellular structures is important for the fabrication of biological substitute in tissue engineering. In this paper, a novel rail-guided multi-microrobotic system was proposed for the assembly of cellular structure. The cellular 2-dimensional (2D) module was fabricated by UV illumination of the crosslinkable hydrogel. The coordinated manipulation among the micromanipulators was performed with newly designed concentric movement along the rail, which realized the arbitrary change of micromanipulator posture. Through the rotation of the end-effectors around the specimen without swapping out the visual field, the manipulation flexibility was improved. The distance information between the micromanipulator and the module was acquired from vision feedback system and utilized for the automatic pick-up of the microstructure. Through the cooperation among multi-manipulators with hybrid motors, the micromanipulation to assemble the 3D structure with 30 nm operation resolution was achieved. Finally, the rail-guided DeSCom system realized the bottom-up fabrication of cellular vascular-like microtube with vision feedback.

Microfluidic devices provide efficient approaches for building cellular tubular structures for in vitro tissue models in tissue engineering. In this paper, we report a novel method of constructing three-dimensional (3D) multilayered tubular structures based on axis translation of two-dimensionally (2D) microstructures inside microfluidic devices. The on-chip fabrication of movable 2D microstructures embedding fibroblasts (NIH/3T3) based on Poly (ethylene glycol) Diacrylate (PEGDA) was reported. Novel two-layered microfluidic devices were fabricated by Polydimethylsiloxane (PDMS), for conducting the fluidic self-assembly of the 2D microstructures. The self-assembly process was experimentally demonstrated. For improving the assembly results, a funneled structure and 3 micro grooves were added inside the microfluidic channel. Improved self-assembly result of constructing a multilayered tubular microstructure with higher efficiency was demonstrated.

In this paper, we achieved three dimensional (3D) assemblies of multi-cell spheroids towards 3D in vitro cell structures. The 3D assembly of cells in vitro is one of the important techniques to reveal cell growth, differentiation and hystogenesis. The techniques can be used for applications in tissue engineering, drug screening, and cell characterization. The multi-cell spheroids were used as building blocks for 3D structure, and thermoresponsive gel was used for spheroids assembly. The mouse myoblast cells C2C12 and mouse fibroblast cells NIH 3T3 were cultured in an ultra-low atachment surface flask. The cells were naturally aggregated in the flask and cell spheroids were prepared in self-assembly process. The rat liver cell RLC-18 was also cultured to prepare spheroids. The thermoresponsive Gel probe (GeT probe) we proposed was employed for assembly of the prepared spheroids in 3D. The handled spheroids by GeT probe were cultured inside the thermoresponsive gel and the cell viability was confirmed. The cultured structure was handled by the GeT probe for further assembly. The results validate that the GeT probe can manipulate spheroids with keeping live condition of cells and achieve 3D cell assembly inside the thermoresponsive gel with arbitrary and precise patterning.

Cellular vascular-like microtubes occupy an important position in tissue engineering for building in vitro tissue models. In this paper, we report a method of constructing three-dimensional (3D) multilayered vascular-like microtubes based on fluidic axis-translation self-assembly of two-dimensional (2D) microstructures inside microfluidic devices. The on-chip fabrication of cell (fibroblasts NIH/3T3) embedded 2D microstructures based on Poly (ethylene glycol) Diacrylate (PEGDA) and biodegradable material Gelatin Methacrylate (GelMa) were reported. A multilayered Polydimethylsiloxane (PDMS) microfluidic device was fabricated for conducting the fluidic self-assembly of 2D microstructures. The fluidic axis-translation self-assembly process was experimentally demonstrated. Multiple hydrogels embedded microtube was constructed. The fabrication of GelMa microstructures was demonstrated. The degradability of cell embedded GelMa microstructures was evaluated by long-term observation, and it shows the great potential of GelMa to be used for constructing cellular vascular-like microtubes.

In human and robot collaborative hybrid assembly cell as we proposed, it is important to develop automatic subtask allocation strategy for human and robot in usage of their advantages. We introduce a folk-joint task model that describes the sequential and parallel features and logic restriction of human and robot collaboration appropriately. To preserve a cost-effectiveness level of task allocation, we develop a logic mathematic method to quantitatively describe this discrete-event system by considering the system tradeoff between the assembly time cost and payment cost. A genetic based revolutionary algorithm is developed for real-time and reliable subtask allocation to meet the required cost-effectiveness. This task allocation strategy is built for a human worker and collaborates with various robot co-workers to meet the small production situation in future. The performance of proposed algorithm is experimentally studied, and the cost-effectiveness is analyzed comparatively on an electronic assembly case.

This paper introduces a novel catalytic mobile micro/nanorobot made only of platinum that realizes nanometer locomotion in hydrogen peroxide solution. The innovative mechanism and principle of the nanorobot are presented. A simple and effective fabrication process by focused ion beam and a stable manipulation method of the nanorobot are demonstrated. The nanorobot can steer or navigate by its finely designed geometry, and keep a stable rotational motion rather than arbitrary and uncertain movement. This paper evaluates the influence of some critical factors on the movement of the nanorobot, such as the concentration and temperature of the hydrogen peroxide solution, and the geometry of a nanorobot. The control of the nanorobot's movement can be realized based on the result of this evaluation. Compared with previous studies, this catalytic platinum nanorobot realizes bidirectional rather than unidirectional movement. The Langevin equation is used to describe the dynamic model of the platinum nanorobot.

This paper introduces a region of interest (ROI) sharing protocol for robots, each of which observes different regions in the same scene. This type of observation is generally referred to as “distributed sensing.” The ROI sharing protocol is implemented based on a concept of semantic stability, which helps to find a stable context by selecting sufficient information from an image or a scene. The semantic stability is formulated based on semantic relatedness and the information gap in the relations found in the ROI. Moreover, the necessary and sufficient information is determined by selecting the best ROI from a given image. Finally, the best ROI is shared between the robots for making cooperation. Experimental results show that the ROI sharing is efficient in terms of task performance and robustness.

The introduction of robotics technology within endovascular surgical procedures has realised accurate catheter navigation and reduced surgeon irradiation. Insufficient force information from the catheter remains a limitation for significant improvement in the performance of these procedures. While recent developments of catheter tip-force measurement sensors have witnessed a notable outcome, packaging complexities and sensor size constraints limit their application. This work presents an approach to catheter tip-force measurement during endovascular surgery simulation. Image processing and photoelasticity are utilized to measure arterial stress and morphological deformation in a carotid artery segment model. Deformation is measured in real-time and conveyed to the user as haptic feedback during tele-operation of a robotic catheter insertion system. A preliminary single user study was completed to realise the potential of force feedback as it is correlated to the level of deformation and stress in the artery model. The results of this haptic feedback are compared with experimental results of the same operator manually inserting the catheter, and also using a computer graphical-user-interface to control the catheter insertion system.

Fault detection functions with learning method of a robotic manipulator are very useful for factory automation. All production has the possibility to fail due to unexpected accidents. To reduce the fatigue of human workers, small errors automatically should be corrected by a robot system. Also a learning method is important for fault detection, because labor of system integrator should be reduced. In this paper, an external thread fastening task by a robotic manipulator is investigated. To discriminate the four states of a task, linear support vector machine methods with two feature parameters are introduced. The effectiveness of the proposed algorithm is confirmed through an experiment and recognition examination. Finally, the ability of linear SVM is compared with artificial neural network method.

This paper presents a new in-vitro simulator that can simulate the new technology of three-dimensional digital subtraction angiography (DSA) to perform a cerebral aneurysm surgery. Then, propose a new technique for the numerical evaluation of the surgical tools applied within this interventional surgery to aid in the design and selection of surgical instruments. Initially, the in-vitro intravascular simulator was constructed, followed by cerebral aneurysm models that were fabricated with highly sensitive photoelastic materials of epoxy resin. Then reconstruct virtual reality modeling of the blood vessel and catheter to record the position information and realize virtual guidance for training. Meanwhile, conduct image processing of photoelastic effects for numerical evaluations of surgical instruments such as catheter insertion and stent expansion. During the stent expansion experiment, the average stress in the selected region of interest caused by the expansion was calculated and compared with the corresponding value obtained before the expansion. The presented simulator and measurement technique can assist in improving a surgeons skills, quantifying the performance of medical mechanisms, and contribute to 3D analysis of stress distribution. This approach can also provide feedback control for robot assisted endovascular systems.

In this paper, we propose a new method to assemble microstructures made of a thermoresponsive gel using hysteresis character of the thermoresponsive polymer solution. This method can be used for 3 dimensional cell assembly by embedding cells in the thermoresponsive gel structures. Gel blocks can be maintained the gel condition by the hysteresis character and the microstructures can be formed by assembling the gel blocks. The temperature distribution around a microheater was analyzed to generate the thermoresponsive gel and avoid thermal damages to cells. The generation of thermoresponsive gel was conducted using the microheater which was embedded in a probe tip and manipulated by a micromanipulator. The fabrication of a gel block was achieved using the hysteresis character and the fabricated gel block was picked and placed by the probe. Cells were embedded in the gel by controlling the position of microheater to avoid the influence of thermal convection flow. The positioning of the gel blocks can be precisely controlled by the micromanipulator. The results indicate the method we propose has a great possibility to achieve 3D cell assembly without large stress to cells during the assembly and cell culture.

3D tailor-made biodegradable scaffold integrated with biological cells or molecules is of great importance for tissue engineering. This paper addresses an improved method for exploring magnetic tweezers in patterning and aligning magnetic hydrogel fiber to fabricate large-scale engineered cell-hydrogel constructs. Magnetic hydrogel fibers were fabricated based on microfluidic device. The fabricated hydrogel fiber is made of alginic acid sodium and with a diameter of 34 μm. Magnetic nanoparticles is added into the alginic acid sodium solution to append magnetic material inside the fibers. The magnetic material inside the hydrogel fiber is regulated by the microfluidic device. Magnetic tweezers system based on solenoid electromagnet is utilized to evaluate the magnetic response of the magnetic hydrogel fiber. Evaluation results show the hydrogel fiber can be maneuvered by the proposed system with a positioning resolution of sub-micro level. The cultivation results of hydrogel fiber with C2C12 cells shows the potential for real applications of the proposed method in tissue engineering.

This paper shows improvement of stability and efficiency for mobility using locomotion selection strategy. First strategy is the selection of a gait relying on locomotion rewards. The locomotion reward has been proposed as an indicator for selection algorithm based on Falling Risk and the moving speed. This strategy has achieved a capability of large changes of uncertainties, such as a steep slope. Second strategy is adjustment of moving speed by the extended locomotion reward that explicitly shows the relationship between the moving speed and Falling Risk. The robot aims at the maximum moving speed without a falling, and removes small changes of uncertainties as a result. We performed an experiment in order to confirm effects of two strategies in an environment that includes a rough terrain as a small uncertainty and two steps as a large uncertainty. The robot improved the moving speed about 37.5% from the case of only using the gait selection strategy.

In this paper, we conducted an assembly of microstructures made of a thermoresponsive gel using hysteresis character of the thermoresponsive polymer solution. This method can be used for 3 dimensional cell assembly by embedding cells in the thermoresponsive gel structures. Gel sheets can be fabricated by micrheaters on a substrate and maintained in the gel condition by the hysteresis character. The microstructures can be formed by assembling the gel sheets using a probe device. The generation of a thermoresponsive gel was conducted using the microheaters made of ITO on a substrate and the generated gel sheets were manipulated by a micromanipulator. The fabrication of a gel sheets was achieved using the hysteresis character and the fabricated gel sheets were picked and placed by the probe. The positioning of the gel blocks can be precisely controlled by the micromanipulator. The results indicate the method we propose has a great possibility to achieve 3D cell assembly without large stress to cells during the assembly and cell culture.

Recently the research about constructing 3 dimensional cell structures is very important for its great potential applications in tissue engineering. In this paper, we report a novel method of constructing multi-layered microstructures embedding cells via microfluidic devices. The on-chip fabrication of movable microstructures embedding fibroblasts (NIH/3T3) based on Poly (ethylene glycol) Diacrylate (PEGDA) was reported. Two approaches for assembling these movable microstructures were presented. One was a manual assembly method based on micromanipulation system and the other one was a self-assembly method based on microfluidic channel. Several manual assembly ways were demonstrated and a tube-shaped microstructure with 17 layers was assembled by an efficient assembly method. A novel microfluidic channel was presented for conducting self-assembly method and a 2-layered experimental microfluidic device was fabricated by Polydimethylsiloxane (PDMS). The self-assembly process of fabricated microstructures via this device was preliminarily demonstrated.

Intelligent cane is a robot developed for assisting the elderly or handicapped people in walking. As a nursing-care device, the cane robot is designed to assist the elderly or handicapped people not only in indoor environments but also in outdoor environments. Therefore the cane robot is required to be smaller and lighter. In addition, it is preferred that the cane robot is movable in omni-directions so that it can be used in various situations. A concept called “intentional direction (ITD)” was proposed to estimate the user's walking intention by analyzing signals from a 6-axis force/torque sensor fixed to the handle of the aluminum stick. Admittance control method was applied to the motion control of the cane robot. In this paper, a new algorithm based on the usage and purpose of an ordinary cane is proposed. In the proposed algorithm, the cane robot is appropriately stopped to support the elderly more effectively. The effectiveness of the proposed method is verified through the experiments.

In electronic manufacturing system, the design of the robotic gripper is important for the successful accomplishment of the assembly task. Due to the restriction of the architecture of traditional robotic hands, the status of assembly parts during the assembly process cannot be effectively detected. In this research, an intelligent robotic gripper - i-Hand equipped with multiple small sensors is designed and built for this purpose, getting the essential parameters for some specific mathematical model. Mating connectors by robot, as an experimental case in this paper, is studied to evaluate the performance of i-Hand. A simple new model is proposed to describe the process of mating connectors, within which the distance between the connector and deformable Printed Circuit Board (PCB) is detected by i-Hand. An online Fault Detection and Diagnosis (FDD) algorithm is proposed. Various possible situations during assembly are considered and handled according to an event driven work flow. The effectiveness of proposed model and algorithm is proved by the experiments.

In this paper, we try to establish new technique that the components of the biological clock are reconstituted into the liposome. In other words, we try to produce a nano size clock, capsulated into the liposome, made by protein molecules. The circadian clock is a basic cellular system found in almost all organisms. This clock generates self-sustained oscillations under constant conditions with a ≈ 24-hour (circadian) period. In cyanobacteria, circadian clock could be reconstituted in vitro only by mixing the three clock proteins, KaiA, KaiB, KaiC, with adenosine triphosphate (ATP). So we reconstitute these proteins and adenosine triphosphate (ATP) into phospholipid-coated microdroplet and confirmed the clock function. The clocks in phospholipids-coated microdroplet indicate long period more than 24 hours. In this case, period length became 35 hour, self-sustaining oscillation was reaming with little dumping. To reveal why the time cycle became long period, we observed localization of Kai proteins in phospholipid-coated microdroplets by using fluorescents labeled Kai proteins under fluorescent (confocal) microscopy. From the observation of localization of Kai proteins, we found KaiB protein was distributed equivalently, on the other hand, KaiC protein was located near membrane of phospholipid-coated microdroplet. These results indicate that different localization between Kai proteins cause long period oscillation and we could control period length depend on calculation data from localization.

Recently, micro-nano robots intended for application to various fields are developed. However, motors which are robot's power are not yet practical. In this paper, to realize the motor which can be applied to micro-nano robot's power source, we established bio-motor by using surface swarming of Vibrio alginolyticus. First, we succeeded in driving the micro gear in the closed micro channel. Next, to transmit power of rotational movement, we fabricated the open micro channel, and succeeded in driving the gear in the open micro channel similarly. In addition, we revealed that ratchet type gear rotated faster than other type. Finally, we assembled the micro gear with shaft. Therefore, it became possible transmitting the power from rotational movement to outside. Thus, we achieved to construct base of bio-motor.

A novel nanotool exchanger system is proposed based on Environmental Scanning Electron Microscope (E-SEM) nanorobotic manipulation system. We proposed to use the E-SEM nanomanipulation system for the analysis of biological specimen using various “nanotools” to realize flexible and complex nano-scale stiffness measurement, adhesion force measurement, cutting, and injection. The E-SEM can use to observe the biological samples in nano-scale and real-time without any drying or dyeing processes. As previous works, we applied the system to manipulate biological specimens, such as Caenorhabditis elegans (C. elegans) and yeast cells. To maintain the livable condition of biological cells, it is important to reduce the exchange time of the nanotools. This is also important to improve the efficiency of biological specimen analysis using various nanotools without break the chamber pressure. This paper presents a novel nanotool exchanger system for exchanging different nanotools within the ESEM chamber. Through the nanotool exchanger system, the following advantages are mainly obtained, 1) it is not needed to open the sample chamber to exchange the nanotools and to evacuate the sample chamber pressure again, 2) it is not needed to operate manually to exchange nanotools, 3) it is possible to recover the nanotools by exchanging new one, 4) it is possible to use different tools continuously. Firstly, the design and fabrication are presented for the proposed nanotool adaptor, nanotool attachment and nanotool holder. Finally, we demonstrate to exchange the different nanotools based on E-SEM nanomanipulation system.

In this paper, an automatic system for single cell analysis inside an environmental scanning electron microscopy (ESEM) was proposed. Single yeast cell was put on an tungsten probe substrate inside ESEM. The endeffector for single cell analysis was fixed to an nanorobotic manipulator, which has three degrees of freedom, i.e. X, Y and Z translation. The real time images during the experiment can be observed by ESEM system in realtime. Therefore, the position of the endeffector and the single cell can be recognized by imaging processing. These position information were used as the feedback signal to control the movement of the nanorobotic manipulator. Finally, a single cell cutting experiment was performed to demonstrate the working mechanism of this system. Two types of cell pattern substrates were also designed and fabricated as the cell analysis chips for the automation single cell analysis in the future.

For the development of medical micro-robotics and robotic manipulation of catheter it is necessary to ensure tissue integrity. In-vitro evaluation of tissue manipulation can be achieved using photoelastic stress analysis and vasculature modeling with photoelastic materials. In this research we propose epoxy resin as photoelastic material for vasculature modeling as it has a larger photoelastic coefficient than previously studied materials and it has a young modulus similar to human vasculature. A model of a saccular aneurysm with bleb was built with the purpose of measuring stress overshoots that enable to differentiate embolization techniques according to the respect for tissue integrity. During embolization using a coil with smaller size than the aneurysm dome diameter, an average area of 0.72 mm2with stress above 90 kPa was measured. This area increased to 0.77 mm2when the dome was touched with the release mechanism of the coil, and to 0.74 mm2for embolization with larger size coil. The presented modeling material and measurement technique is useful for tissue respect quantification for micro-mechanisms evaluation.

Constructing different patterns of cells and immobilizing these cells inside certain structures are very important issues for artificial tissue engineering. In this paper, we present methods of forming line pattern of yeast cells by dielectrophoresis (DEP) and immobilizing patterned cells by photo-crosslinkable resin. High speed cell pattering by DEP and on-chip fabrication of microstructure which contains patterned yeast cells is demonstrated. In order to applying DEP force for forming cell pattern, several novel microelectrodes are fabricated by Indium Tin Oxides (ITO) which are coated on the glass. The two kinds of DEP responses of yeast cell (W303) and the precise experimental parameters of them are confirmed. Based on negative DEP phenomenon, cell traps generated by microelectrode are demonstrated. Position control and transportation of yeast cells is performed by using cell traps. Besides, a cell trap matrix is fabricated and high speed cell pattering is performed. The experimental results show that the cell line patterns which contain hundreds of yeast cells can be formed by DEP within 1 second. The on-chip fabrication for arbitrary shapes of microstructures based on Poly Ethylene Glycol Diacrylate (PEG-DA) is reported. With the cell patterning by DEP and immobilizing by on-chip fabrication, microstructure which contains 3 lines of yeast cells is fabricated in the microfluidic channel, inside PEG-DA and NaCl solution.

The traffic congestion is growing in urban area these days due to the rapidly increasing number of automobiles. One of the traffic problem solutions is to increase the flow rate of a particular traffic artery. To make the vehicle smaller and narrower might be a good idea. We developed a new conceptual Narrow Tilting Vehicle (NTV) that has one front wheel and two rear wheels. The proposed NTV is very narrow and all three wheels can tilt to improve the stability during turning. We also derive a new switching dynamical model of the NTV. This model considers several states including normal running, temporary running with one rear wheel not on the ground and totally falling down. Based on this model, a simulation platform is established, which is useful to test different control methods and to investigate dangerous driving situations in case hurt drivers in real experiments. The effectiveness of proposed dynamical model is verified through comparison study of simulations and corresponding experiments.

Magnetic field has been used for manipulation of micro-robots; in this research we use it for scaffold fabrication. Magnetic sugar particle (MSP) was used as porogen to control pore size, pore structure and pore density in the scaffold. We studied the influence of the strength of magnetic fields for controlling the coating thickness of unmagnetized MSPs during the fabrication of sheet-like scaffolds. The experimental relationship between magnetic flux density and the thickness of MSP layer was illustrated. Furthermore we investigated the infiltration capacity of poly(L-lactide-co-ε-caprolactone) (PLCL) which was used as scaffold material on the MSP clusters. 5% and 10% PLCL solutions were employed in the experiments. After polymer casting and removal of the sugar template, spherical pores were generated inside scaffold, the thickness evaluation of a single layer scaffold was carried out and the cytocompatibility experiment of NdFeB powder used in fabrication of MSP was confirmed with human umbilical vein endothelial cells.

We proposed a micro fluidic device to control the position of Caenorhabditis elegans (C. elegans) and to analyze the condition of C. elegans as a bioindicator during its lifespan. In this device, we can filter C. elegans depending on size and control the position of C. elegans to culture and test C. elegans and to measure the capacitance change. The capacitance change depends on the body volume of C. elegans. Through the correlation with the capacitance change and the body volume of C. elegans, the body volume of C. elegans is assessed without imaging system. The proposed micro fluidic device was implemented using a PDMS layer and a glass substrate that were bonded together. The PDMS layer had a valve system and pattern rows to filter, culture and test C. elegans. A pair of electrodes is used to measure the capacitance change. In this study, we filtered C. elegans into the same size by filter and one C. elegans was introduced into a chamber row to be cultured and tested. And it was confirmed the correlation between the capacitance change and the body volume of C. elegans. And the proposed micro fluidic device will be applied to observe the effect of chemical or toxicant like heavy metal (Cd) on C. elegans as bioindicator.

This paper deals with a method of locomotion selection based on Falling Risk and moving efficiency. The robot estimates information from sensors by solving state equation. The robot evaluates the Falling Risk as an indicator of uncertainty. Falling Risk is derived from measured information by using Bayesian Network. Locomotion selection during walking is modeled as a Semi-Markov Decision Process and the most appropriate locomotion is selected by using the greedy algorithm. As a result, the robot can move in the environment that is difficult to travel by single locomotion mode, maintaining the maximum moving efficiency.

Quantification of human skills is a challenge for simulator based medical training, particularly for endovascular intervention. For that purpose it is needed to measure different biometric parameters from the user and additionally measure the interaction between endovascular instruments and vasculature models membrane. For that purpose in this research we present an optical sensor for encoding linear and rotational motion of the catheter through the insertion port. Additionally we present two studies for measuring tissue integrity, time to complete a task, reaction time, and wasting motion using two populations of expert and beginner. The optical encoder showed an average error of 0.39mm and 10.78deg. In both studies the presented cyber-physical system is useful to identify the users with qualities closer to the expert among users with low performance.

Micro-nano robots intended for application to various fields are developed. However, motors, which are robot's power, are not yet practical. In this paper, to realize the motor, which can be applied to micro-nano robot's power source, we established bio-motor by using surface swarming of Vibrio alginolyticus. We succeeded in controlling movement of surface swarming by ratchet shape micro channel and then driving the micro gear in the closed micro channel. As a next step, to transmit power of rotational movement, we fabricated the open micro channel and micro object (floating pillar, micro gear etc.) and succeeded in driving the object in the open micro channel. In addition, we revealed that rotational power of floating pillar by deformation of nano probe. Finally, we assembled the micro gear with shaft like crank. Therefore, it became possible transmitting the power from rotational movement to outside. Thus, we achieved to construct base of bio-motor.

For multi-contact robot motion, a closed chain is formed by robot links and the environment. This paper proposes a new methodology named “key joint method” for reducing the energy cost by adjusting an internal stress inside a closed chain. Firstly, we analyze the internal stress theoretically taking the degrees of freedom (DOF) and the number of position actuated joints into consideration, then a practical key joint method is proposed by changing a suitable redundant position controlled joint to be force control. After that, a parametric family is introduced for representing various of possible motions subjected to the robot dynamics and other constraints. Finally, a general optimization method is proposed for planning an energetically efficient multi-contact robot motion taking the motion trajectories and internal stress into consideration. As an example, the pace gait ladder decent motion is taken to explain the principle and realization of the proposed method. As experimental evaluation shows, the key joint method is effective for reducing the energy cost in the multi-contact motion.

This paper presents a novel selective nano-injection method using fluorescent nanobeads based on nanomanipulation for in-vivo single cell analysis. The nanomanipulation system was constructed under hybrid microscope. The hybrid microscope consists of the optical microscope (OM) and environmental-scanning electron microscope (E-SEM) to realize biological specimen analysis by optical imaging including fluorescent imaging, and nano-scale manipulation by E-SEM imaging. Based on the bio-nano manipulation system, we propose a nanoinjection method by nanoprobe insertion and nanobead embeddedness. The nanoprobe was designed to have four tips to fix single nanobead. It is fabricated by focused ion beam (FIB) process. Its nano-scale size is considered to be important for minimal damage to a biological specimen. In this work, as biological specimen, the Caenorhabditis elegans (C. elegans) was used. It is one of the important model organisms for various diseases analysis. The nanoinjection technique is applied to transport fluorescent materials or specific biological organism into a specific cell for in-vivo experiment of C. elegans. The proposed system is considered to be important as future nano-surgery system for life innovation using model organism.

Single cell's mechanical property characterization is important for the understanding of the cell's condition and activity. In this paper, an automatic nanomanipulation system was proposed for single cell mechanical property characterization inside an environmental scanning electron microscopy (ESEM). A nanoneedle was fabricated from AFM (atomic force microscopy) cantilever by FIB (focused ion beam) etching technique. The nanoneedle was fixed to a nanorobotic manipulator, which has three degrees of freedom, i.e. X, Y and Z translation. Single yeast cell was put on an tungsten probe substrate inside ESEM. The position information of the nanoneedle and single cell were used as the feedback signals to control the movement of the nanorobotic manipulator. Finally, the stiffness of the single cell was measured using the nanoneedle driven by the automatic nanomanipulation system.

For the development of artificial intelligent diagnosis for cerebrovascular intervention, it is desirable to forecast the growth of cerebral aneurysms. In order to achieve such purpose, it is needed to evaluate wall shear stress, strain, pressure, deformation and flow velocity in the aneurysm region. In this research, we focus on in-vitro strain and deformation measurements of cerebral aneurysm models, and propose a cyber-physical system, in which a scaled-up membranous silicone model of cerebral aneurysm was built and integrated with a specialized pump for the pulsatile blood flow simulation, and a vision system was constructed to measure the strain on different regions on the model with pulsatile blood flow circulated inside. Experimental results show that both distance and area strain maxima were larger for the aneurysm neck (0.042 and 0.052), followed by the aneurysm dome (0.023 and 0.04) and then by the main blood vessel section (0.01 and 0.014), which were complemented with computer fluid dynamics simulation for the inclusion of wall shear stress, oscillatory shear index and aneurysm formation index. Medical imaging data of the cerebral aneurysm in 2008 and 2011 was obtained. Diagnosis results have concordance with the aneurysm growth in 2011. The presented measurement method offers an option for measuring strain and deformation to be complementary with computer fluid dynamics and photoelastic stress analysis for advanced diagnostic in the endovascular surgery.

For tissue engineering, it is very important to construct cell patterns and immobilize patterned cells inside certain structures. In this paper, we present methods of forming cell pattern by dielectrophoresis (DEP) and immobilizing cells by photo-crosslinkable resin inside microfluidic chips. High speed cell manipulation, including patterning and concentration control by DEP is demonstrated. Movable microstructure embedding cells is on-chip fabricated. Several microelectrodes are fabricated by Indium Tin Oxides (ITO) and Cr/Au. The two kinds of DEP responses of yeast cell (W303) and other particles are experimentally confirmed. Based on negative DEP phenomenon, line and circle patterns of cells and microbeads are high speed performed. Cell manipulation for patterning is completed within 1 second. The on-chip fabrication of movable microstructures embedding cells based on Poly Ethylene Glycol Diacrylate (PEG-DA) is reported. The microfluidic chip with separated patterning and fabrication areas is fabricated. With the cell concentration control by DEP and on-chip fabrication method, movable microstructures embedding microbeads of which the concentration is controllable are fabricated in the microfluidic channel, inside PEG-DA and NaCl solution.

An intelligent cane robot (iCane) was designed for aiding the elderly who have muscle weakness on lower limbs. A commercial omni-directional wheels robot was used as an omni-directional mobile base, and an aluminum stick was installed on the base of cane robot. A Concept called “intentional direction (ITD)” was proposed for estimating the user's walking intention by analyzing the signal of a 6-axis force/torque sensor which is fixed to the handle of stick. A universal joint driven by two DC motors was designed to control the posture of the stick. As a care-nursing device, the cane robot was designed to assist the elderly in both indoor and outdoor environments. Therefore the size and weight of cane robot should be minimized. But in that case, there is high risk that the cane robot would be pushed over by the user. In this paper a constrained nonlinear multivariable algorithm was designed to optimize the stable posture of cane robot. By controlling the posture of stick, the maximums sufferable torque moment which lead to cane robot falling over can be increased. The experimental results show that the stability of cane robot can be enhanced effectively.

Toward to realizing a novel drug delivery system, a simulation system is considered to be important for a future analysis of it. In this paper, a novel, miniature, and energy-efficient bio-mimetic propulsion concept was proposed. The antibody binding technique is developed and used to attach bacteria to liposome's surface for enhancing liposome mobility. Bacteria and liposome are strongly combined through antibody. Consequently, the effect of antibody when bacteria attached to liposome is studied experimentally. The stochastic nature of bacterial propulsion of liposome is investigated experimentally and analytically. It is shown that antibody plays an important role in attaching bacteria to liposome and the liposome with bacteria moved broader compared to the liposome without bacteria. Statistical calculation matches well with experimental data.

The microstructures are expected to be used as the components of on-chip single cell analysis system such as cell manipulation and measurement tools. We previously proposed a method to fabricate and assemble the microstructures within a microfluidic channel. Micro objects with arbitrary shape are fabricated by illumination of patterned UV-ray through the mask. The arbitrary shape objects are made of the photo-crosslinkable resin on the microfluidic device under a microscope and these objects are manipulated by optical tweezers. In this paper, we report a method of hybrid-microstructures fabrication which improves the trapping efficiency by optical tweezers. The hybrid-microstructure is composed of the photo-crosslinkable resin and polystyrene beads. The manipulation speed of the hybrid-microstructure increases when the optical tweezers trap the polystyrene beads. This is because the trapping efficiency of spherical configuration is higher than that of planar shape. We fabricate this hybrid-microstructure and evaluate the trapping efficiency compared with normal microstructure.

In this paper, we established the transport systems for micro object by using surface swarming of Vibrio alginolyticus. First, we confirmed that V. alginolyticus were able to transport the micro beads. In this experiment, we used YM19 and YM19ΔcheY that were a kind of the variant strain of V. alginolyticus appropriate for surface swarming. Next, we examined relationship between the transport speed and the diameter of the micro bead. The micro channel was applied to control the cell movement. And then we succeeded in causing the rotational transport of object through this method.

This paper presents a novel nano-injection method by nanoprobe insertion based on environmental-scanning electron microscope (E-SEM) under hybrid microscope. The hybrid microscope is designed to combine the optical microscope (OM) and E-SEM to realize biological specimen analysis by optical imaging including fluorescent imaging, and nano-scale manipulation by E-SEM imaging. Based on the bio-nano manipulation system, we propose a nano-injection method by nanoprobe insertion. The nanoprobe is designed to have a sharp tip to insert the probe into biological specimen. It is fabricated by focused ion beam (FIB) process. The nano-scale size is important for minimal damage to biological specimen. The Caenorhabditis elegans (C. elegans) is used as a target biological specimen, which is one of the important model organism for diseases analysis. The nano-injection technique is needed to transport fluorescent materials or specific biological organism into specific cell for in-vivo experiment. The proposed system is considered to be important as future nano-surgery system for life innovation using model organism.

In this paper, a novel oscillating nano knife for single cell cutting at its native state was proposed. The nano knife with a small edge angle 5° was fabricated from a commercial AFM cantilever by focused ion beam (FIB) etching. The spring constant of the nano knife was calibrated by nanorobotic manipulation method. A piezo actuator was employed to generate the vibration of the nano knife. The oscillating amplitude response to the applied voltage was calculated based on the realtime image observation. Single yeast cell (W303) cutting using oscillating nano knife was performed based on the nanorobotic manipulation system inside an environment-SEM. The maximum cutting forces and the slices angle were measured from the deformation of the nano knife beam and the single cell. The result showed the oscillating nano knife was capable and effective for single cell cutting task.

In this paper, we propose new probe device which can realize soft handling of single cells using thermal gel. In general, probe devices are one of the important devices for single cell manipulation. However, conventional probe devices have some problems: damage to the manipulated cells and difficulty to release the manipulated objects by the effect of surface force. As one solution of these problems, we propose "soft handling probe" in this paper. The probe has an electrode as a microheater. The thermoresponsive polymer can be gelled when a current is applied to the electrode in the thermoresponsive polymer solution. The electrode was fabricated by cupper wire and sputtering of gold on the probe. Thermal gelation of the thermoresponsive polymer was realized at the fabricated probe tip. The manipulation of micro objects and assembly of three dimensional structures were demonstrated by the probe. The handling of yeast cell and liposome were also realized by the probe. It is expected that the probe can realize the soft handling by the generated thermal gel and realize the precise positioning by reducing the effect of surface force.

Manufacturing industry tends to employ more flexible assembly cells for High-Mix, Low-Volume production. We has proposed an innovative human and robot hybrid assembly cell within this purpose to solve the problem of persistent growing cost for human resources and now and again changes in programs and configurations for robots, and to achieve a high manufacturing efficiency. One of the key issues is to find out the optimal way of allocating the assembly subtasks to both human and robot. In this paper, a model for assembly strategy generation and selection for human and robot coordinated (HRC) cell assembly is proposed. A Dual Generalized Stochastic Petri Net (GSPN) model is theoretically researched and then built based on a practical assembly task for human and robot coordination. Based on GSPN, Monte Carlo method is carried out to study the time cost and payment cost for possible strategies, and Multiple-Objective Optimization (MOOP) method related Cost-effectiveness analysis is adopted to select the optimal ones. We demonstrate the effectiveness of this approach by comparing the simulation and experimental results.

This paper reports a magnetic steering method for controlled porogen fabrication of scaffold for blood vessel regeneration. The method described involves generating gradient magnetic field by a combination structure of Helmholtz coils and Maxwell coils to propel particularly prepared magnetic sugar particles (MSPs) moving in fluid environment at desired trajectory and forming a specified 3D shape as templates for particulate leaching. The movement properties of MSP are theoretically analyzed and the corresponding dynamic mechanics model is established. Further the magnetic field distributions inside the combined coils are calculated and optimal control parameters of coils configuration are obtained. Preliminary motion control experiment is also conducted to prove the feasibility of proposed method. The result demonstrates that MSP cluster can be manipulated with average speed of 0.25 mm/s for a cluster of 12 MSPs and 0.116 mm/s for a cluster of 37 MSPs with the proposed coil system and used for improving interconnection of MSP dot patterns.

In this paper, we try to establish newly technique that the components of the biological clock are reconstituted into the liposome. In other words, we try to produce a nano size clock, capsulated into the liposome, made by protein molecules. The circadian clock is a basic cellular system found in almost all organisms. This clock generates self-sustained oscillations under constant conditions with a ≈ 24-hour (circadian) period. In cyanobacteria, circadian clock could be reconstituted in vitro only by mixing the three clock proteins, KaiA, KaiB, KaiC, with adenosine triphosphate (ATP). So we reconstitute these proteins and adenosine triphosphate (ATP) into phospholipid-coated microdroplet and confirmed the clock function. The clocks in phospholipids-coated microdroplet indicate long period more than 24 hour. In this case, period length became 35 hour, self-sustaining oscillation was reaming with little dumping. To reveal why the time cycle became long period, we observed localization of Kai proteins in phospholipid-coated microdroplets by using fluorescents labeled Kai proteins under fluorescent (conforcal) microscopy. From the observation of localization of Kai proteins, we found KaiB protein was distributed equivalently, on the other hand, KaiC protein was located near membrane of phospholipid-coated microdroplet. These results indicate that deferent localization between Kai proteins cause long period oscillation.

Micro/Nano robots have attracted scientific attention to develop novel technologies such as drug delivery systems. Recently, flagellated bacteria have been used as the driving force of microobjects to develop bacteria-driven microrobots. In this paper, we propose a method of smart manipulation of multiple bacteria-driven microobjects with single manipulated guiderobot based on bacterial autonomous movement, named ¿SMARTBOT¿, for enabling arbitrary and low cost manipulation of multiple bacteria-driven microrobots. We verify the capability of smart manipulation of multiple bacteria-driven microobjects based on bacterial autonomous movement by using micro/nano pipettes instead of a guiderobot. For the fabrication of the guiderobot and the cargo driven by the bacteria, the fabrication of the arbitrarily-shaped microobjects using photo lithography technique is demonstrated. Additionally, we demonstrate the remote control using optical tweezers and driving using flagellated bacteria of the fabricated arbitrarily-shaped microobjects.

We consider a 24-degrees-of-freedom monkey robot that is supposed to perform brachiation locomotion, i.e. swinging from one row of a horizontal ladder to the next one using the arms. The robot hand is constructed as a planar hook so that the contact point about which the robot swings is a passive hinge. We identify the 10 most relevant degrees of freedom for this underactuated mechanical system and formulate a tractable search: (a) introduce a family of coordination patterns to be enforced on the dynamics with respect to a path coordinate; (b) formulate geometric equality constraints that are necessary for periodic locomotion; (c) generate trajectories from integrable reduced dynamics associated with the passive hinge; (d) evaluate the energetic cost of transport. Moreover, we observe that a linear approximation of the reduced dynamics can be used for trajectory generation which allows us to incorporate the gradient of the cost function into the search algorithm.

This paper presents a sensor fusion between intravascular ultrasound (IVUS) and magnetic trackers for constructing the virtual reality three dimensional models of the blood vessels. We propose this approach for vasculature modeling as part of a guidance system relying on augmented reality for assistance during aortic stent graft deploy. This guidance will facilitate the alignment of the holes on the stent graft walls with the renal and mesenteric arteries ramifications. First we studied the disturbances on the magnetic tracker measurements induced by IVUS emitter after assembling the two sensors together. Then we performed a scan with the hybrid probe inside a blood silicone model submerged into a water tank, captured and fused data from both sensors. The dispersion of samples increased less than 1mm in the evaluated locations while the IVUS was activated. This enabled the construction of a three-dimensional model in virtual reality of the blood vessel model relying on the sensor fusion.

This paper presents a novel homogeneous power management system for heterogeneous self-reconfigurable multi-module systems consisting of active power suppliers, diverse power consumers and hybrids. To optimize functionality of each module, a concept separating functionality from power supply is proposed and applied in immobile payload items which can be combined with mobile modules in varying configurations autonomously. By allowing consumers and power sources to connect to common power bus, the concept enhances flexibility, reusability and performance of modular robotic systems. The power management system based on the concept is implemented and evaluated. The experimental results show that power is efficiently transferred in power bus among individual modules, consumer modules without battery packs can be kept alive during switching, and the power management system can protect individual modules from hardware faults reliably.

The on-chip fabrication and manipulation of microstructures are expected to be applied for single cell analysis system such as cell manipulation and measurement tools. In this paper, we previously present a methodology for fabricating and assembling microstructures inside a microfluidic channel. By the illumination of patterned UV-ray through the mask under a microscope, microstructures with arbitrary shape are made of the photo-crosslinkable resin inside microfluidic device. The microstructures are fabricated at the desired place inside microfluidic channel and manipulated by optical tweezers. Based on the technique which can manipulate multiple points simultaneously by high-speed scanning of a single laser with galvanometer mirror, a rotational microstructure made of a microgear and a rotation axis is assembled and rotated. We also report two methods of solution replacement inside microfluidic channel which reduces viscosity of solvent in order to improve manipulation performance. By adjusting the concentration of photo-crosslinkable resin and replacing solution components, the viscosity of solvent inside channel can be changed. The manipulation speed of the rotational microstructure increases when the viscosity of solvent decreases, because the viscosity resistance for the movement of microstructure is weaker inside lower viscosity solvent. We fabricate rotational microstructures inside lower viscosity solvent and evaluate the movement efficiency compared with microstructures inside former high viscosity solvent.

In this study, we present an omni-directional cane robot for aiding the elderly and handicapped people walking. The motion control problem is investigated for both normal and abnormal walking conditions. In the case of the user's normal walking aided by the cane robot, a concept called “Intentional Direction (ITD)” is proposed. Guided by the online estimated ITD, we apply the admittance control method in the motion control of cane robot. The gravity compensation is also considered because the user is possible to walk on a slope. For the abnormal walking, we mainly studied the case of user's falling down. The Center of Gravity (COG) of user can be estimated from the angle of an inverted pendulum which represents human model. Fall prevention algorithm based on the relationship between user's COG and the cane is proposed. This algorithm is also applied in the motion control of cane robot. The proposed method are verified through experiments.

Micro/nano robots have been actively studied toward the realization. Now, the micro living organisms have been used as the driving forces for the micro objects. To achieve the fine manipulation of bio driven micro objects, the manipulation methods have to be established. Therefore, the local environmental control technique is desired to manipulate a single cell and to analyze the detailed properties. We have developed the local environmental control system with nano/micro dual pipettes, and achieved the quick-response and iterative rotational speed manipulation of Na+-driven flagellar motor, which is a rotary molecular machine, by switching the local spout between Na+-containing and Na+-free solutions with dual pipettes. In this paper, we upgrade our local environmental control system with nano/micro dual pipettes to achieve the quantitative and long-time-stable manipulation of the rotational speed of the Na+-driven flagellar motor. We demonstrate fine and long-time-stable rotational speed manipulation of Na+-driven flagellar motor by simultaneous local spouts of Na+-containing and Na+-free solutions using dual pipettes with controlling the spouting velocities independently. And, as the driving force, the rotational torque generated by the flagellar motor is estimated at the range from ~2.3×103to ~2.8×103pN·nm.

Real-time and accurate stress calculation in walls of vasculature is desired to provide catheter insertion robots of feedback control without changing the catheter stiffness and lumen. This feedback source has also applications in endovascular surgery simulation for human skills and medical tools evaluation. For that purpose we consider photoelastic effect, as birefringence produced by light retardation relates with the stress inside the photoelastic materials. In this research a polariscope was designed for urethane elastomer vasculature models, the photoelastic coefficient of urethane elastomer was measured, and the camera system was calibrated to quantify and reduce error of the measurement system. An average error of 3.6% was found for the pressure range of 70-189 mmHg inside the model of urethane elastomer, this enables to calculate accurately stress in vasculature models during Human Blood Pressure Simulation (HBPS). That way we will be able to compare in a closed loop stress produced by HBPS and by the catheter motion when manipulated by a robot.

This paper describes a 3-D biped walking over rough terrain. The robot is modeled as the special 3-D inverted pendulum that can change the length. The dynamics of the 3-D inverted pendulum is modeled as 2-D autonomous system by applying the Passive Dynamic Autonomous Control (PDAC) that is based on the assumption of point-contact of the robot foot and the virtual holonomic constraint as to robot joints. We analyze the stability of the 2-D autonomous system by use of Poincarée map, and derive the stable range over rough terrain. By applying the virtual compliance control to an actual robot “Gorilla Robot III”, the angle of the pendulum is modified. Finally, the 3-D biped walking over rough terrain is realized by use of the Gorilla Robot III.

This paper describes walk-to-brachiate transfer of a multi-locomotion robot (MLR). The MLR has multiple types of locomotion such as biped walking, quadruped walking and brachiation. This transfer is carried out through vertical ladder climbing as the robot must raise its body to start brachiating. As a result we have designed two stable transfer motions from walk to climb and from climb to brachiate, while contact situations and constraints of the robot are changing during the transfers. In addition, we have proposed a control algorithm by considering the reaction force from environment, and the setting of parameter is based on a kinetic model of the robot in order to tolerate relative position errors between the robot and its environments such as rungs of the ladder. The robustness of the designed motions with error corrections is experimentally verified.

It is desirable for endovascular surgery simulation to describe with quantitative data the interaction between the catheter and the blood vessel model wall to make an objective evaluation of the procedure. Photoelastic stress analysis in straight segments of multi-layered models was used for that purpose. In this research we study the error introduced by stress direction on the magnitude measurements, for photoelastic stress analysis. And we propose a scanner for three dimensional visualization of photoelastic stress analysis. As result, we quantified that the maximum contribution of error from stress direction in the first half of the fringe is 2.52% for the stress magnitude measurements. Three-dimensional stress visualization was obtained in segment of straight vasculature with an average error in sample slices of 10.73%, 4.55% and 3.18% for inner pressures of 80, 120 and 160mmHg respectively.

This paper introduces the concept of semantic evaluation of Region of Interest (ROI) for intelligent robots. The intelligent robot must have the capability of understanding situations. The first step of understanding of the situation is to find where to focus on and how to behave. Focusing on some particular area or region needs selection of the objects of interaction relevant to the context. Moreover, the focused area needs to be semantically evaluated to quantify the semantic relations. In this paper, we first detect interacting objects based on dynamic interaction. Then we recognize probable objects using Dynamic Bayesian Networks. Using the probable objects and a mutual supplementation model, we determine the contextual object. We form ROIs based on possible combinations of objects and the contextual object. Finally, we semantically evaluate each ROI. Various experimental results are provided to illustrate our method.

The applicative field of activities of robots which have only one locomotion strategy is limited. As a mean of enhancing the mobile range, it is necessary to have various locomotion modes. Therefore, we focus on dynamic transitions between several kinds of locomotion modes adapting to environmental changes. In this paper, we aim to realize a stable locomotion along some unknown test courses with transition between biped and quadruped walks. To achive this transition, we propose a method to get environmental information and internal conditions. Robot plans locomotion based on recognition of test courses and estimate stability of walking using Bayesian Network. The effectiveness of proposed method is verified by experiments.

There has been increasing interest in a type of underactuated mechanical systems, mobile-wheeled inverted-pendulum (MWIP) models, which are widely used in the field of autonomous robotics and intelligent vehicles. Robust-velocity-tracking problem of the MWIP systems is investigated in this study. In the velocity-control problem, model uncertainties accompany uncertain equilibriums, which make the controller design become more difficult. Two sliding-mode-control (SMC) methods are proposed for the systems, both of which are capable of handling both parameter uncertainties and external disturbances. The asymptotical stabilities of the corresponding closed-loop systems are achieved through the selection of sliding-surface parameters, which are based on some rules. There is still a steady tracking error when the first SMC controller is used. By assuming a novel sliding surface, the second SMC controller is designed to solve this problem. The effectiveness of the proposed methods is finally confirmed by the numerical simulations.

This paper proposes a three-dimensional biped dynamic walking algorithm based on passive dynamic autonomous control (PDAC) which is previously proposed. The robot dynamics is modeled as an autonomous system of a three-dimensional inverted pendulum by applying the PDAC concept that is based on the assumption of point contact of the robot foot and the virtual constraint as to robot joints. Due to autonomy, there are two conservative quantities named ldquoPDAC constantrdquo, that determine the velocity and direction of the biped walking. We also propose the convergence algorithm to make PDAC constant converge to arbitrary value, so that walking velocity and direction is controllable. Numerical simulation results validate proposed algorithm.

There has been an increasing interest in a kind of underactuated mechanical systems, mobile wheeled inverted pendulum (MWIP) models, which are widely used in the field of autonomous robotics and intelligent vehicles. Robust velocity tracking problem of MWIP systems is investigated in this study. In the velocity control problem, model uncertainties accompany uncertain equilibriums, which make the controller design become more difficult. A sliding mode control (SMC) method based on a novel sliding surface is proposed for the systems, which are capable of handling both parameter uncertainties and external disturbances. By assuming the specially designed sliding surface, the proposed SMC controller is capable of eliminating the steady velocity tracking error. The asymptotical stability of the closed-loop system is achieved through selecting sliding surface parameters in terms of some rules. The effectiveness of the proposed methods is finally confirmed by numerical simulations.

In this paper, we propose a semi-closed microchip which can realize the probe type manipulation in the microchip with the internal environment sealed off from the external environment. Long-term experiments can be conducted for in-situ culture and analysis of cells by the semi-closed microchip. The semi-closed microchip has a bath in the middle of microchannel to allow the insertion of micropipettes into the microchip. The bath is sealed off by thin oil film to prevent the evaporation of the solution in the bath. The seal by the oil film can maintain even if micropipettes are inserted into the bath and pulled out from the bath because the oil film can fill the hole by its surface tension. The seal by the oil film was evaluated by measuring the weight of the bath after 12/24 hours. To use the semi-closed microchip for cell culture and cell analysis, the exchange of the solution in the bath was demonstrated. It was also demonstrated that the cell fixation with the thermo sensitive gel in the proposed semi-closed microchip by fabricating the ITO electrodes as heaters in the bath. Cell culture and the target cell harvesting were conducted by the semi-closed microchip. The proposed semi-closed microchip can be used for cell culture, cell analysis and cell harvesting under a microscope as the biological applications for single cell analysis.

This paper addresses a three-dimensional biped dynamic walking control based on Passive Dynamic Autonomous Control (PDAC). In our previous work, the robot dynamics is modeled as a two-dimensional autonomous system of a three-dimensional inverted pendulum by applying the PDAC concept. In addition, the convergence algorithm based on conservative quantities named ¿PDAC constant¿ was proposed, so that walking velocity and direction is controllable. In this paper, we apply our control framework to an experimental robot ¿Multi-locomotion Robot¿; then the performance and the efficiency of the proposed control algorithm are verified by experiments.

The microstructures are expected to be used as the components of on-chip single cell analysis system such as cell manipulation and measurement tools. In this paper, we propose the on-chip fabrication method of microstructures with minimum dimensions of 5 ¿m. The micro objects with arbitrary shape are fabricated by illumination of patterned UV-ray through the mask. The arbitrary shape objects are made of the photo-crosslinkable resin on the microchip under a microscope. The polymerized micro-objects, which we call as ¿Microtools¿, can be used for the single cell analysis. The microtools are fabricated at the desired place on the microchip in less than 1 second. Additionally, the microtools are manipulated by optical tweezers. By high-speed scanning of a single laser with galvanometer mirror, it is able to manipulate multiple points simultaneously. Using this technique, the rotational microstructure composed of the rotation axis and the microgear is assembled and rotated. We propose the two method of microstructure assembly. The assembled rotational microstructure is evaluated about the rotation speed depending on the laser power.

Optical adhesion control of a functional gel microtool, made of hydrophilic photo-crosslinkable resin, was developed for on-chip cell manipulation. The functional gel microtool used can be manipulated by optical tweezers and functionalized by spiropyran chromospheres, which is a photochromic polymer. Spiropyran chromospheres were used for temporal cell adhesion of the gel microtool. The adhesiveness of the gel microtools was controlled by photo irradiation. The gel microtools adhere to glass and other gel microtools, in an electrolyte solution of adjusted concentration, after ultraviolet (UV) illumination. By controlling the electrolyte concentration, the adhesion to cells can be selected as either permanent or temporal cell adhesions. UV illumination caused the cell to adhere to the gel microtool, while VIS illumination detached it from the gel-microtool. We also produced a pH sensing gel microtool by modifying the gel microtool with a pH indicator, bromothymol blue (BTB). The pH value was measured by detecting the color of the gel microtool with calibrated color information. Local measurements of the ambient pH value of a single yeast cell were performed by a ring shaped gel microtool and by immobilizing the cell on the surface of the pH sensing gel microtool.

This paper presents the local stiffness measurements of Caenorhabditis Elegans (C. elegans) by buckling nanoprobes through the nanorobotic manipulation system inside an environmental-scanning electron microscope (E-SEM). C. elegans has complex outer and inner structures constructed by approximately one thousand cells. For example, the lateral alae are the surface fine structure by seam cell body. In this paper, their fine structures were observed by E-SEM directly; without any drying or dyeing processes. The observation environments are controlled under different E-SEM chamber pressures for clear observation of C. elegans. The local stiffness of C. elegans was measured by buckling measurement method of the nanoprobe fabricated by focus ion beam (FIB) etching at the tip of atomic force microscope (AFM) cantilever. The measurement position can arbitrarily be controlled by the nanorobotic manipulator inside the E-SEM. In this work, from experimental results, the measured elasticity on lateral alae was 1.6 times larger than it around lateral alae. This local stiffness measurement technique can readily be applied to reveal unknown biological local stiffness, cell health conditions and novel cell diagnosis.

We proposed a fabrication method for multiscale transparent arteriole and capillary vessel models and demonstrated the fabrication of microchannels with circular cross sections ¿10 - 500 ¿m. First, we demonstrated fabrication of ¿10 - 500 ¿m arteriole and capillary vessel block models using photolithography. The circularity of fabricated ¿10, 50, and 500 ¿m microchannels were 84.0%, 61.5%, and 82.3%, respectively. Flow experiments demonstrated that these channels had no leakage. Next, we proposed a fabrication method for ¿100 - 500 ¿m arteriole membrane models, which connect larger membrane models and smaller block models. These models were prepared with grayscale lithography and a wax and PVA (polyvinyl alcohol) mixture material. The proposed approach overcame the brittleness of a previous sacrificial model fabricated by ink jet rapid prototyping. The membrane model had a circular cross section with a channel circularity of 90%. Finally, we succeeded in making transparent membranous and block arteriole model with which we can simulate blood circulation.

Drivers are distracted by the large amount of information displayed, which raises the driver's visual and cognitive workload. Conventional hierarchical searching, which invariably requires time even for those familiar with systems, is another factor. Our proposed user-adaptive interface consists of user modeling using a hidden Markov model (HMM) and symbol matching which is the reconfiguration of a preferred navigation sequence. The interface learns a user's navigation patterns based on accumulated navigation sequences. The navigation sequence is reconfigured by the user model and a clue. The symbol matching is performed in compliance with the user's selection and the navigation sequence is recommended to the user. Experimental results showed that reconfiguring the navigation sequence and switches reduced navigation reaction time.

This paper proposes an intelligent monitoring system based on emotional model in sensor networks. Emotional models are very useful to understand human behaviors. First, we explain the recent works on emotional models, and discuss the applicability of emotional models to real world problems. Next, we propose an emotional model composed of emotion, feeling, and mood. These three components are coupling, but their time scales are different. Next, we explain perceptual system based on image processing and the monitoring system based on the proposed emotional model. Finally, we discuss the effectiveness of the proposed method through several experimental results.

This paper describes an approach for real time detection and evaluation of region of interest (ROI) based on saliency and relevance. In our approach, we have considered moving background updating technique to adapt with real environment with camera equipped with mobile robot. We have introduced a new decision making criterion which selects the relevant objects based on human psychology of relevance. We have provided some experimental results which prove to be promising and realistic with this approach.

A novel on-chip environment measurement with functional gel-microtool was developed. Environment measurement gel-microtool was fabricated by connecting the gel-microbeads impregnated with indicators in a microchip. In this paper, Bromothymol blue (BTB) and Bromocresol green (BCG) were employed as pH indicators. BTB and BCG have the different indicator range. Rhodamine B is temperature sensitive fluorescent dye and is used for temperature measurement. Gel-microbead is made by salting-out of hydrophilic photo-crosslinkable resin and is manipulated by optical tweezers. Moreover, gel-microbead is polymerized by UV illumination and connected to other gel-microbead under an electrolyte solution. The connection of gel-microbeads is performed by contact of gel-microbeads under UV illumination. Environment measurement gel-microtool with an arbitrary shape is fabricated by connection of the gel-microtool impregnated with arbitrary indicator. Multiple environments measurement gel-microtool included with several indicators is realized by assembly of the gel-microbeads impregnated with different indicators. Environment measurement is performed by detecting the color and the fluorescence intensity of each gel-microbead. We succeeded in the on-chip fabrication of the environment measurement gel-microtools such as circular pH measurement gel-microtool and wide range pH measurement gel-microtool in a microchip.

Technologies to develop scaffolds with controlled pore layout and porosity have great significance in tissue engineering. As one method of scaffold fabrication, porogen leaching has been commonly used to control pore size, pore structure and porosity in the scaffold. In this paper, we describe a novel approach to fabricate 2D and 3D porous biodegradable scaffolds made of poly(L-lactide-co-ε-caprolactone) by using magnetic sugar particles as porogens. First, ferrite micro/nano particles were encapsulated in sugar microspheres to make them magnetized. After sieving magnetic sugar particles, those diameter-controlled particles were attracted by a magnetic force to form an assembled template for polymer casting. A magnetic field with polka-dot pattern was also utilized to align particles on desired positions. After polymer casting and removal of the sugar template, spherical pores were generated inside scaffold. For future application in vascular tissue engineering, we extended the scaffold fabrication to straight tubular scaffolds by winding 2D porous sheets on sacrificial molds. The biocompatibility of the developed scaffold was confirmed by viable cells after 4-day culture.

An animal has a characteristic ratio of forefoot and rear legs so that its morphology can adapt to the living environment. Likewise, the structure of robot should be better fitted the locomotion in the working environment. This paper derives an optimal structure of the quadruped robot, which minimizes the sum of joint torques of the robot. Minimization of the joint torque allows to reduce the joint acceleration in walking motion, and hence to reduce energy consumption. Numerical simulation analyzed joint torques in each limb length and slope angle under walking on a slope. The optimal rate of rear leg length (RRL) is derived by the simulation as the physical structure. Our analysis suggests that the joint torque will increase as the slope angle becomes steeper in the case that the rear legs are shorter than forelegs. On the other hand, the joint torque will decrease as the slope angle is declined in the case that the forelegs are shorter than the rear legs. Experimental results validated the simulation analysis.

A compact force sensor with the AT-cut quartz crystal resonator was developed. The quartz crystal resonator has the characteristic that the resonance frequency changes by the external force, which achieves high sensitivity, high-speed response, and wide range of measurement by a simple structure. Also it has the superior feature in the temperature and frequency stability. In the past, the quartz crystal resonator had been hardly applied to the force measurement because of low degree of mechanical characteristic, that is, it is weak to stress concentration by bending. The objective of this study is to construct the sensor mechanism that safely maintains the quartz crystal resonator for the external force with flat structure. We designed and analyzed a novel retention mechanism of the quartz crystal resonator. The proposed force sensor is flat, small, and sensitive. It can be applied to several usages such as medical treatment and contact force detection of human.

A three-wheeled omni-directional cane robot is designed for aiding the elderly walking. Possible move modes are analyzed and a corresponding hybrid model is constructed to describe walking behavior. A concept called intentional direction is presented to denote the moving intention of a human. Based on experiments and some assumptions, dynamic model of intentional direction is obtained as well as its online estimation method. A new admittance control scheme is presented based on intentional direction, which provides natural and intuitive human machine interface. Experiment results show the effectiveness of the design.

This paper introduces a vertical ladder climbing of the humanoid robot only by the posture control without any external sensors. The humanoid robot does not have any special structure for fixing the body to the ladder. The robot maintains the body on the ladder by its grippers like human does. As a problem of this locomotion, a free gripper position of the climbing robot is not controllable because a yawing of the robot body around the axis connecting a supporting gripper and foot on the ladder is not fixed. To solve this problem, the momentum around AOY caused by the gravity is used to control the yaw motion of the body so that the various gait such as pace gait and trot gait could be realized in a ladder climbing maneuver. The algorithm of ladder climbing with recovery motion is experimentally verified by using ldquomulti-locomotion robot(MLR)rdquo which is developed to achieve various types of locomotion such as biped, quadruped walking and brachiation.

This paper proposes a new evaluation method of feeling in switch-pressing motion based on the surface electromyogram (sEMG) signals. We introduce a hypothesis that one always predicts a necessary strength when exerting onepsilas strength to act on an object and some moderate differences between the predicted force and the result would lead to a sense of comfort. In order to validate the hypothesis, a series of experiments are conducted on switch-pressing motion and corresponding feeling. First, the predicted muscular force is estimated from sEMG which reflects our intension. Second, we derive the difference between the predicted muscular force and the actual reactive force of the switch (variation of difference from prediction - stroke pattern; D-S pattern). Finally, we evaluate the feeling evoked by the switch-pressing motion based on the D-S pattern. Experimental results show correlativity between evaluation by our proposed method and subjective evaluation, and validate our working hypothesis that some moderate differences between the prediction and the result would lead to a sense of comfort.

As one of dynamics-based control of biped walking, some researchers presented the control method to take advantage of robot dynamics directly by use of point-contact state between a robot and the ground. We proposed passive dynamic autonomous control (PDAC) previously (2004) as one of point-contact methods. PDAC expresses the robot dynamics as a 1-dimensional autonomous system based on the two concepts: 1) point-contact 2) virtual constraint (proposed by Grizzle et al. (2001) and Westervelt et al. (2004)). We actually realized 3D dynamic walking by means of proposed method, however stability is not proved and the convergence domain is not clear. Thus, this paper finds the convergence domain of the previously proposed controller and proves the stability by the Liapunov theory. Finally, the correctness of stability proof is confirmed by the numerical simulation.

In this research, we propose a method to construct an artificial blood vessel scaffold with patient-specific complex 3-dimensional shape and biocompatible porous polymer membrane adapted for cell cultivation, by introducing salt leaching technique into a fabrication technique for patient-specific 3D blood vessel model proposed by authors. In this method, a membranous PVA (polyvinyl alcohol) structure of desired 3-dimensional blood vessel shape was fabricated based on CT data. And the PVA structure was dip coated with polymer solution made by dissolving the Caprolactone (3wt%) and NaCl particle (27wt%) into chloroform (organic solvent), Finally, the NaCl particle and the membranous PVA structure were both eluted from the structure by dissolving these materials under water, and finally a patient-specific blood vessel scaffold with desired 3D vascular shape was constructed. Presented scaffold has the mechanical compliance similar to human blood vessel and provides porous polymer structure appropriate for cell cultivation.

In this paper, a series of in situ nanofabrication techniques of nanostructures, including cutting, bending and welding of carbon nanotubes (CNTs), inside a field emission scanning electron microscope (FE-SEM) is reported. In the CNT cutting technique, a CNT was exposed to a low energy beam assisted with 1 seem oxygen gas flow. The proposed technique is effective being capable of cutting a CNT in less than 1 minute. It was found that, although the total pressure of specimen chamber reached 10-2Pa, high speed cutting occurs only in the area close to the nozzle. The presence of oxygen gas in the vicinity of the CNT can be applied also for the bending of CNT, if some conditions of the cutting technique are changed. These include the increase of the acceleration voltage and/or setting the oxygen gas nozzle farther from the sample, and/or reducing the irradiation time. Using the proposed bending method the angles larger than 90deg can be formed and the location of the kink can be set accurately. It is also shown, that tungsten can be deposited on a substrate by the electron-beam-induced deposition (EBID), if the oxygen of the proposed cutting technique is replaced by W(CO)6. In this paper, these three nanofabrication methods were exploited in creation of a two dimensional (2D) nanostructure, the letters N and U, and a three dimensional (3D) nanostructure, the letter N. The 2D letters were constructed from 6 CNTs assembled on a substrate while the 3D letter N was bended from a single CNT and fixed to stand on a substrate. Based on the high performance of the proposed techniques, it is suggested that the cutting, bending, and welding techniques inside SEM will become widely utilized in the fabrication and assembly of nanodevices and in the characterization of nanomaterials.

A local pH measurement method in a microchip using a functional gel-tool was developed. We used salting-out gel-tools impregnated with Bromothymol Blue (BTB), which is a pH indicator. The gel-tool is made of hydrophilic photo-crosslinkable resin. The primary constituent of this photo-crosslinkable resin is polyethyleneglycol. A solution mixed with photo-crosslinkable resin, BTB, high concentrations of an electrolytic solution are stirred, and gel beads impregnated with BTB are obtained. Gel-tools are cured by UV-ray and adhere to the glass plate, but we can manipulate them by the optical tweezers. We can measure pH value locally from the color of gel-tool using calibrated color information in YCrCb color space. We succeeded in measuring local pH value with the pH sensing gel-tool by manipulating and locating it at the desired point in the microchip.

The purpose of the present study is to control human biological rhythm and life cycle by optimization of awakening timing. We developed a wearable interface for controlling awakening time named "BRAC (biological rhythm based awakening timing controller)". BRAC could estimate bio-rhythm by pulse wave from finger tip and send awake signal to user. An ordinary alarm clock operates according to set times that have to be set in advance. However, humans have a rhythm in their sleep, which affects one's sleep depth and wake-up timing. We consider the simplest way to control or reset human's bio-rhythm or life style is to optimize the awakening timing and the sleeping hours. We examined the relationship between controlling awakening timing based on autonomous nerve rhythm and equilibrium function. Our findings suggest indicate that the prototype "BRAC" could evaluate user's biological rhythm and awakes user at the time optimized for physical function of equilibrium.

We performed in situ measurements of mechanical properties of individual W303 wild-type yeast cells by using an integrated environmental scanning electron microscope (ESEM) - nanomanipulator system. Compression experiments to penetrate a cell wall of an individual cell under two difference conditions, i.e. ESEM (600 Pa) and high vacuum (HV) (about 3 mPa) modes have been conducted. Data from the experiments clearly show a significant increase of about twenty five times of penetration force values from ESEM mode to HV mode; i.e. 152 nN and 4 muN for 5 mum cell size with sharp tip indenter. This can be further confirmed from quantitative estimation of average cell rigidity through the Hertz model, i.e. ESEM mode (2.16 plusmn 1.21 MPa) and HV (20.58 plusmn 2.09 MPa) for all cell sizes with sharp tip indenter. Further analysis also revealed that the size of the cells can influence its mechanical strength. As the size of the cell increases, the compression force needed to penetrate its wall also increases. From these experimental results, we can conclude that the force needed to penetrate a single cell does not only depend on the internal factor, i.e. cell size but also being influenced by the external factors, i.e. the environmental conditions.

We developed a novel technique to manipulate lipid nanotubes in 3D by laser tweezers in water solutions. Laser tweezers are well known as one of the noncontact manipulation methods used in a closed space. We reported on 3D 6DOF manipulation of microbeads using 3D Synchronized Laser Micromanipulation (SLM), however, the blur is generated in the microscope image when multiple points at different height are trapped by scanning the focal point of laser. Moreover, it is difficult to manipulate a nano scaled rod-like object stably in 3D, since optical trap force is weak. To manipulate a lipid nanotube for example, firstly, we newly developed an observation system to improve blur of image by synchronization of shutter timing of CCD camera and laser scanning. As a result, we can obtain a clear image of the targets at different height while manipulating them. Secondly, we developed functional gel microtools which can adhere to the lipid nanotubes. We succeeded in controlling the position and orientation of the lipid nanotubes by using 3D SLM with shutter timing control method and novel functional gel microtools.

This paper describes a control for the brachiation robot with holonomic constraint. In our previous work, the brachiation controller is composed of two actions: swing-back and locomotion. The purpose of swing-back is to excite a robot so as to achieve the locomotion successfully, while locomotion action is to move forward by releasing the ladder with the backward arm in the direction of locomotion and gripping the target ladder with another arm. However, the conventional control can not apply brachiation in irregular ladder. And the convetional control was not consider energy efficiency. Thus, a novel method to achieve brachiation in irregular ladder and an energy-efficient brachiation by exacting a swing-back during locomotion is proposed. Experimental results show that the proposed method can improve the locomotion action as much as over 30% in energy consumption.

A force sensor with quartz crystal resonator has the characteristic that the resonance frequency changes by the external force, which achieves high sensitivity, high-speed response, and wide range measurement by a simple structure. Also it has the superior feature in the temperature and frequency stability. On the other hand, the quartz crystal resonator had been hardly applied to a dynamic force measurement because of low degree of mechanical characteristic, that is, it is weak to the impact, bend, and tension. The objective of this study is to construct the sensor mechanism that safely maintains the quartz crystal resonator for the external force with flat structure. We designed and analyzed a novel retention mechanism of the quartz crystal resonator for the flat structure. The proposed force sensor is flat, small, and sensitive enough to be applied to several usages such as medical treatment and dynamic contact force detection of human.

This paper presents a problem of odor source localization in a dynamic environment, which means the odor distribution is changing over time. Most work on chemical sensing with mobile robots assume an experimental setup that minimizes the influence of turbulent transport by either minimizing the source-to-sensor distance in trail following or by assuming a strong unidirectional air stream in the environment, including our previous work. However, not much attention has been paid to the natural environment problem. Modification Particle Swarm Optimization is a well-known algorithm, which can continuously track a changing optimum over time. PSO can be improved or adapted by incorporating the change detection and responding mechanisms for solving dynamic problems. Charged PSO, which is another extension of the PSO, has also been applied to solve dynamic problems. Odor source localization is an interesting application in dynamic problems. We will adopt two types of PSO modification concepts to develop a new algorithm in order to control autonomous vehicles. Before applying the algorithm for real implementation, some important hardware conditions must be considered. Firstly, to reduce the possibility of robots leaving the search space, a limit to the value of velocity vector is needed. The value of vector velocity can be clamped to the range [-Vmax, Vmax]; in our case for the MK-01 Robot, the maximum velocity is 0.05 m/s. Secondly, in the standard PSO algorithm there is no collision avoidance mechanism. To avoid the collision among robot we add some collision avoidance functions.

Laser tweezers is suitable for manipulation of a single microscopic biological object. It can manipulate micro bioobject without contact in the closed space. Single cell manipulation is important for biological research, and 3D 6DOF manipulation (position control and orientation control) is useful technique in many biological experiments. In this paper we propose 3D synchronized laser manipulation system that can manipulate multiple micro-objects along separate trajectories in 3D space. The position as well as the orientation of microbeads can be controlled using this system. We succeeded in achieving orientation control of the microbead by using the laser trapped microtools. We demonstrate experimentally 3D 6DOF manipulation of microbeads

This paper proposes the control method of biped walking with heel-off motion. Heel-off motion made it possible to avoid the problem for the impact shock at foot-contact to break the stabilization of walking. The 3D motion is separated into lateral and sagittal motion and each motion is designed individually under the assumption that each motion is possible to be treated independently each other. We adopt the approximate 1-mass model in both planes and derive the dynamics based on these models. It is assumed that the lateral motion is relevant to heel-off motion. On the other hand, in the sagittal plane, there are two phases: 1) the center of rotation (contact point) is ankle joint. 2) the center of rotation is toe. In phase 2), heel-off motion is designed to diminish the impact shock at foot-contact. By applying PDAC to the dynamics, phase around the contact point can be derived. By means of this phase of dynamics, it is possible to inspect heel-off motion analytically. We design the stabilizing controller for each plane and confirm the convergency of dynamics with the numerical simulation

An in vitro patient-specific vascular model, for simulating endovascular intervention is presented. Proposed vascular model reproduces the 3-dimensional vessel lumen structure using CT/MRI information with 13 mum resolution, and it also reproduce the physical characteristics of arterial tissue (elastic modulus and friction coefficient). Furthermore, in this paper, we propose a novel method to evaluate the stress on vasculature which is applied by surgical operations. This method allows quantitatively evaluating 3-dimensional stress conditions in real-time during surgical simulation. Finally, we constructed a comprehensive surgical simulation system, which reproduces whole human aorta structure (with more than Imm inside diameter), reproduce patient-specific pulsatile blood streaming, allowed to evaluate the stress applied to the aorta structure by surgical operations with almost same manner and environment as the practical endovascular intervention. Consequently proposed model, evaluation method and resultant system provides a very valuable platform for evaluating the performance of surgical robots and instruments developed by developers and researchers, and surgical procedures

In this paper, we propose an environment-adaptive antipersonnel mine detection system called Advanced Mine Sweeper. Advanced Mine Sweeper is developed based on sensing technologies, access-control technologies and system integration technologies for safe and effective demining procedure after the Level II survey. Advanced Mine Sweeper consists of a sensing vehicle/unit, an access vehicle, and an assist vehicle. The sensing vehicle/unit is composed of an integrated sensor and a small-reaction sensor head manipulator. The access vehicle is parked facing a mine field in order to control the sensing unit position in a global area using its boom. The assist vehicle is parked keeping some distance from a mine field. It controls the sensing vehicle/unit and access vehicle and then displays the processed sensing information for landmine detection, receiving sensing information and sensing position. By using this system, experiments in the field buried dummy landmines were carried out for the utility and performance evaluation

This paper presents a problem of odor source localization in a dynamic environment, which means the odor distribution is changing over time. Odor source localization is an interesting application in dynamic problems. Modified particle swarm optimization is a well-known algorithm, which can continuously track a changing optimum over time. PSO can be improved or adapted by incorporating the change detection and responding mechanisms for solving dynamic problems. Charged PSO which is another extension of the PSO has also been applied to solve dynamic problems. We adopted two types of modified concepts of PSO for a new algorithm in order to control autonomous vehicles in more realistic environment where a speed limitation of the robot behavior and collision avoidance mechanism should be taken into consideration as well as the effect of noise and threshold value for the odor sensor response, also positioning error of GPS sensor of robot. Simulations illustrate that the new approach can solve such dynamic problems in advection-diffusion odor model environment

We report a single tungsten nanowire successfully grown by controlling the distance between the emitter and substrates with a robotic nanomanipulator moved at a speed of 15 nm/s. When we draw the emitter far from the substrates during electron emission, the longest nanowire at the tip can grow continually, because the electron field at the tip is stronger than the other parts of nanowires. Although multiple nanowires grow at the beginning, the result is that only one nanowire can grow continually at the tip of carbon nanotubes (CNTs). We also show tree-like nanowires on the tip of a CNT without inter-electrode control. These nanowires were induced by field emission, with tungsten hexacarbonyl as precursors. The nanowire's geometric properties were characterized with transmission electron microscopy (TEM) and its composition was detected with TEM energy dispersive X-ray spectrometry (EDS). The EDS spectrum showed that the nanowires are mainly made of tungsten and carbon. The degradation of CNT emitter is an important problem and influences the device's stability and lifetime. We propose that the growth of nanowires can be used for modifying degraded emitters

There are many deformable objects such as papers, clothes, and ropes in life space of a person. Robots need skills to manipulate deformable objects, in order to take active parts in such space. However, it is difficult for robots to manipulate deformable objects well and possibility of failure to operate deformable objects cannot be denied. Therefore, shape recognition method for deformable object manipulation is required, that has hyper degrees of freedom structures. Thus in this paper, we propose a description method of conditions of ropes using a topological model and knot theory. And, we also propose a recognition method to obtain the structure of rope from sensor information through the CCD cameras when a robot manipulates a rope. The effectiveness of recognition method against a method using three-dimensional data is verified through an experiment

We propose a new tactile sensor utilizing piezoelectric vibration. This tactile sensor has a high sensitivity, wide measurement range, pressure resistance, flexibility, and self-sensing function. This tactile sensor comprises two piezoelectric materials. One is used for the vibration of the sensor element and the other is used for the measurement of the change in mechanical impedance induced by an external force. We achieved the wide measurement range by implementing two ideas. One was to apply the external force to the sensor element through an elastic body and the other was to use two or more modes of vibration. Moreover, for the elastic body, it is preferable to use a material whose elasticity and viscosity are easily changed by an external force, such as a gel. In this study, first, this tactile sensor was analyzed, and then its characteristics were derived. The analytical results qualitatively corresponded to the experimental results. Next, a prototype tactile sensor was fabricated and evaluated. The evaluation results showed that this tactile sensor can measure a pressure of 2.5 Pa or less and a pressure of 10 kPa or more and its pressure resistance is 1 MPa or more

In situ fabrication and electrostatic actuation of a telescoping multi-walled carbon nanotube are presented. The inner core of the telescoping nanotube is actuated by applied bias voltage with a certain gap inside a vacuum chamber. From modeling analysis, the electrostatic forces are mainly driven force for actuation. At the experimental section, one end opened telescoping multi-walled carbon nanotube (MWCNT) is directly observed inside a transmission electron microscope (TEM). The telescoping MWNT is fabricated by peeling off outer layers through destructive fabrication process. Its inner core is extended and retracted with applied DC bias voltage. These processes have been done through a hybrid nanorobotic manipulation system, which are integrated nanomanipulators inside a scanning electron microscope (SEM) and a TEM. From experimental and analytical results, the possibility of nano-scale actuator applications using telescoping MWCNT with precision has been presented

There are many electric power generators employing dynamos. However, most of them require large mechanical energy input at a time to get large electric power output. This task is not easy for elders because of heavy load. Therefore, we aimed to develop a new ubiquitous power generator suited for light power input. In order to generate large electric energy with light force, we propose a new generator mechanism to store mechanical energy using a spiral spring and gears. Large mechanical energy is stored in the spring by iteration of light force input. We designed a mechanism which can store mechanical energy in the spring by rotating an input lever several times with light force. The energy is restored to rotate the dynamo at high speed to generate electric energy efficiently. While restoring the mechanical energy, reverse rotation of the input lever is avoided by the clutch. Analysis as well as experiment of the proposed mechanism was performed here for optimal design of gear train. As an application, a power generation device which generates energy from door motion is shown to see effectiveness of this mechanism

The essential challenge in the future ubiquitous networks is to make information available to people not only at any time, at any place, and in any form, but with the right thing at the right time in the right way by inferring the users' situations. Several psychological experiments show that there are some associations between each user's situations including the user's emotions and each user's task selection. Utilizing those results, this article presents a situation-based task selection mechanism that enables a life-supporting robot system to perform tasks based on the user's situation. Stimulated by interactions between the robot and the user, this mechanism constructs and updates the association between the user's situation and tasks so that the robot can adapt to the user's behaviors related to the robot's tasks effectively. For the user adaptation, Radial Basis Function Networks (RBFNs) and associative learning algorithms are used. The proposed mechanism is applied to the CRF3 (Character robot face 3) system to prove its feasibility and effectiveness. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 973–1004, 2006.

We propose an energy-based control method for a multilocomotion robot to improve the stability of continuous brachiation. The target continuous brachiation is an effective locomotion from one bar to another exchanging a kinetic energy with potential energy like a pendulum. Our control strategy for the continuous brachiation is to control the swing-back action so that the robot pumps up the feasible energy to grasp a target bar, and then the locomotion action is designed based on the symmetric motion of a pendulum in order to conserve the total energy: summation of the kinetic and potential energy. The proposed controller is implemented on a new type of mobile multilocomotion robot named “Gorilla Robot III” whose dimensions are mimicking those of a gorilla. Continuous brachiation on various uniform ladders is experimentally achieved with this robot. The experimental results show the validity of our control algorithm. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 1025–1043, 2006.

The concepts of meaning and intentionality play a central role in understanding animal and human intelligence, and they are crucial for creating artifacts with intelligent behavior and robust autonomy in real-life scenarios. The Intentional Dynamical Systems Symposium IDS'04 was held in Memphis, Tennessee, April 26–27, 2004, and it gave a forum to researchers working on the intensively developing interdisciplinary area of dynamical approaches to embedded cognition, based on self-organized development of autonomous systems. The present issue contains selected papers from the symposium addressing dynamical aspects of intentionality and intelligent behavior. All papers have been carefully peer reviewed to meet the standards of the journal. Contributions to this issue cover neuro-physiological foundations of human cortical dynamics, computational neuro-pharmacology and hippocampal modeling, development of KIII models for cognitive map generation, utilization of KII and KIII sets as logical gates and associative memories for odor recognition, evolutionary development of control for autonomous robot, and incorporating emotional representations in interactive robots. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 875–879, 2006.

Nanoscale linear servomotors with integrated position sensing are investigated from experimental, theoretical, and design perspectives. Prismatic motion is realized using the interlayer motion of telescoping multiwalled carbon nanotubes (MWNTs). Position sensing can be achieved by monitoring field emission or by measuring resistance change between an MWNT and a gold substrate during sliding movement. Experimental results demonstrate resolution in the nanometer range. Actuation experiments demonstrate the feasibility of a linear nanoservomotor with integrated position sensing based on field emission. A local "kink"-like fluctuation of emission current is observed, which is caused by the change of the protruding length of the nanotube core, thus demonstrating the potential of using emission as a "linear encoder." The complete extension of the inner core is observed and the electrostatic force is calibrated to be tens of nano-Newtons for individual nanotubes-16.5 nN under a 30-V bias. These results demonstrate the possibility of fabricating linear servomotors at the nanometer scale with integrated position sensing. Note to Practitioners-Nanometer scale actuators and sensors that can provide motion and measurement with nanometer-order resolution will enable new industrial applications in which only a few atoms or molecules are measured, transported, or processed. Linear servomotors will play a significant role in such applications because they provide precision prismatic motion directly without requiring a conversion from rotary to linear motion. Nano linear servomotors are experimentally and theoretically investigated in this paper. The devices take advantage of the ultra-low interlayer friction of a multiwalled carbon nanotube (MWNT). Position sensing feedback is achieved by monitoring field emission, which depends on interelectrode distance, or by measuring resistance change between an MWNT and a gold substrate during sliding movement. Whereas this paper targets long-term nanotechnology contributions, some intermediate results are ready for applications in the near future. The interlayer sliding motion demonstrated would enable the building of devices, such as Gigahertz oscillators and attolitter nanosyringes, and the sensors used for position feedback could find applications independently in a macro or microscale machine for detecting proximity, touch, displacement, or orientation.

In this paper, we develop the lateral motion control based on Passive Dynamic Autonomous Control (PDAC) in order to solve two following problem in previous paper: 1) the step-length control in the sagittal plane results in the delay of one step cycle since walking period is not controlled taking the sagittal control effect into consideration 2) error of the lateral dynamics is big since the effect of the sagittal motion on the lateral dynamics is neglected. At first, the walking period is controlled, by adjusting the amplitude of side-to-side rocking motion. Secondly, the value to lengthen the lateral inverted pendulum is decided according to the sagittal motion effect on it. By means of this new lateral control in addition to sagittal step-length control, the 3-dimensional stable dynamic walking based on the robot inherent dynamics is realized.

Nanoscale linear servomotors with integrated position sensing are investigated from experimental, theoretical, and design perspectives. Prismatic motion is realized using the interlayer motion of telescoping multi-walled carbon nanotubes (MWNTs). Position sensing can be achieved by monitoring field emission or by measuring resistance change between a MWNT and a gold substrate during sliding movement. Experimental results demonstrate resolution in the nanometer range. Actuation experiments demonstrate the feasibility of a linear nano servomotor with integrated position sensing based on field emission. A local “kink”-like fluctuation of emission current is observed, which is caused by the change of the protruding length of the nanotube core, thus demonstrating the potential of using emission as a “linear encoder”. Complete extension of the inner core is observed and the electrostatic force is calibrated to be tens of nano-Newtons for individual nanotubes— 13.3 to 23.3 nN for voltages from 20 to 30V. These results demonstrate the possibility of fabricating linear servomotors at the nanometer scale with integrated position sensing.

In this paper, we present a control method to realize continuous brachiation. The target brachiation is basically divided into two actions: a swing action and a locomotion action. In order to realize the continuous brachiation effectively and stably, it is necessary to control these actions according to the total energy of the system. Because brachiation has been modeled as a pendulum-like motion and the amplitude of the oscillation determines whether the robot can grasp the target bar or not. In consideration of this point, an energy based control method is proposed and introduced into the swing action controller. The purpose of this method is to control the angular velocity of the swing action in order to satisfy the desired energy evaluated by the distance of bars. Experimental results show that the robot can successfully achieve smooth, continuous brachiation.

In recent years, single cell experiment has become very important for investigating unknown cell properties. We developed a novel technique to investigate individual cell properties on a chip using newly developed cell manipulation method by laser tweezers with the photo - crosslinkable resin. We propose new fabrication method of functional microtools, such as colored microtool, fluorescent microtool, cell binding microtool, rotation free microtool, rope shaped microtool, on a chip. These microtools are made of photo - crosslinkable resin. Colored microtool and fluorescent microtool are for cell manipulation using Image processing with low cost. Cell binding microtool is made for high - speed transportation of target cell. Rotation free microtool is made for position control and precise force measurement of cell and DNA. Rope shaped microtool is for versatile manipulation. Laser tweezers is employed to position control of microtools. We used mercury lamp for UV - ray illumination at the local area for combination of microtools. We succeeded in fabrication of our functional microtools and manipulation of cell in the microchip.

In this paper, grasping strategy using deformation of soft finger is addressed. Soft fingers, which are made of macromolecular and have large elastic deformation, have gotten a lot of attention. Soft fingers have a peculiarity that high friction force, which stabilizes a grasping condition, is generated by expansion of contact area between tip of soft finger and grasping object. However, until now nobody focuses on the fact that deformation of soft finger enables multi-fingered hand to generate force to manipulate a object which has high aspect ratio and restricted by environment. Accordingly, we focus on a task to pick up a thin plate on a floor using deformation of soft finger. The effectiveness of grasping strategy is confirmed by experiments.

We propose a novel tactile sensor, of which sensitivity and sensing range is adjustable. This sensor is a mechanical resonator sensor using a piezoelectric bimorph which measures elastic deformation of media by external force. The sensor is robust and has self-sensing capability. We derived the relationship between sensor output and spring constant at each vibration mode by the piezoelectric analysis and vibration analysis. The validity of sensor was demonstrated by experiment. As an application, a robot fingertip with tactile sensor was fabricated and evaluated.

A novel approach appropriate for rapid separation and analysis of single cell by concomitantly utilizing noncontact laser manipulation and locally thermo sensitive hydro gelation is proposed in this paper. We have employed a single laser beam as optical tweezers for separating a target cell and locating it adjacent to a fabricated transparent micro heater. Simultaneously, the target cell is immobilized or partially entrapped with thermo sensitive hydro gel by heating up the micro heater. The state of the thermo sensitive hydro gel can be switched from sol to gel and gel to sol reversibly by controlling its temperature through heating up and cooling down the micro heater. Having got rid of the other unwanted cells by the high speed cleaning flow in microchannel, the entrapped cell will be isolated effectively. It is possible to collect the immobilized target cell after analysis or culture process by switching of the micro heater and releasing the cell from the entrapment. We have demonstrated that the proposed approach is feasible for rapid manipulation, immobilization, cleaning, isolation and extraction of a single cell. Experiment results are shown here.

In this paper, the new control method to realize 3D natural dynamic walking based on the 3D robot inherent dynamics is proposed. The proposed method describes robot dynamics by use of a 3D inverted pendulum model and applies passive dynamic autonomous control (PDAC) to it. By utilizing the polar coordinate system to express the robot state around the contact-point between robot and the ground and applying PDAC, it is possible to express the 3-dimensional dynamics as 1-dimensional autonomous system. Due to autonomy, this 1D dynamics has the conservative quantity named PDAC constant. We build the stabilizing controller by means of PDAC constant and analyze the walking based on the 1D dynamics. Finally the proposed method is tested by experiment.

In this paper, we propose an in vitro patient-tailored biological model of human cerebral artery, an innovative platform for simulating intravascular neurosurgery to evaluate medical robots and devices. This anatomically accurate model reproduces 3-dimensional configuration of individual arteries with an artery-like thin membranous structure made of silicone elastomer. Its modeling resolution is 13 /spl mu/m. Presented modeling methodology also allows constructing any hollow structure, which is suitable for robot evaluations, making use of CAD. Presented model also reproduces the physical properties of arterial tissue with errors less than 5% (that include elastic modulus, poisson's ratio and frictional coefficient). Thus the cerebral arterial model reproduces not only the behavior of arteries caused by surgical operations, but also the dynamic behavior of surgical robots and devices (e.g. elastic deformation and slip/stick motion). Furthermore, we also propose a novel method that allows developers to evaluate 3-dimensional stress condition on arterial wall, which is caused by surgical operations, by making use of the photoelastic effect. As there are almost no realistic hardware platform enough to fairly evaluate medical robots and devices, it should provide an advanced testing environment for developing robots and other various medical equipments, especially for intravascular neurosurgery.

The purpose of this research is to control human state and biological rhythm. The system has to be adaptive and intelligent because it must deal with human information including personal differences. As a first step to achieve the function, we try to estimate a human's state in sleep using a wearable sensor device, under less physical movement than daytime. In the next step, we try to control human biological rhythm using the method to estimate human sleep state. We consider the simplest way to control human's sleep is to control awakening timing and sleep time. The proposed system can estimate human sleep quality and rhythms, and provide stimuli based on wake up timing. The system uses only pulse wave to estimate sleep quality because the pulse wave can be measured more easily than PSG.

Field emission properties of individual multi-walled carbon nanotubes (MWNT) have been investigated and applied to several nano devices. Field emission current changes with the distance between the tip of a carbon nanotube (CNT) emitter and a counterpart anode, which can be applied as the principle for an approaching sensor to detect nanometer scale distance by the observation of field emission current in real time. Higher field emission current in microampere-scale from a CNT emitter has been shown strong enough for performing electron-beam-induced deposition (EBID) without obvious degradation of emitters. EBID with CNT emitters can provide much higher specific deposition rate, potentially better productivity due to the possibility to be used in parallel, and richer metallic composition as introducing organometallic precursors such as W(CO)/sub 6/ as presented In this work. Energy dispersive X-ray spectrometry (EDS) analysis on deposits from W(CO)/sub 6/ shows that the mass of tungsten reaches up to over 80% among the compositions.

Isolation and separation of the target microbe is quite important. We propose a new touch sensor for separation of the target microbe on the plate using a micromanipulator with the glass pipette. Principle of this touch sensor is based on detection of mechanical impedance change after contact of the vibrating pipette tip with the plate. We improved the fixation method of the sensor with the pipette as well as electrode design of the sensor. We performed the FEM analysis to improve sensitivity of this sensor. The prototype sensor has high sensitivity and high rigidity and is excellent in durability. This sensor is sensitive enough to protect the fragile pipette tip from abrupt collision. Thus, separation task of the microbe by the micromanipulator under the microscope is improved.

Laser micromanipulation is suitable for non-contact manipulation of a small object, such as a bacteria and microbe, at the closed space. We proposed synchronized laser micromanipulation (SLM) for the trajectory control of the multiple targets by the single laser. We used the laser scanning system for scanning of the focal point of laser in high speed to realize simultaneous trajectory control of multiple objects. Condition for secure transportation of multiple objects is derived analytically and verified through the experiment. We used SLM for indirect manipulation of the microbe by the microtools, which are directly manipulated by SLM. Here we propose the force measurement method using SLM. Recognition of the microtool is improved by using a fluorescent microbead as a microtool.

This paper proposes passive trajectory control (PTC), a new control method of Acrobot, and discusses its application to biped walking robots. PTC makes the first joint passive and makes the point contact between the whole robot system and the ground, then actuates other joints according to the motion of the passive joint. Due to this interlock, the whole robot system becomes autonomous and the controller is independent of time. Hence, PTC makes it possible to design the robot motion based on not the trajectory of time, but the dynamics around the contact point. In this paper, we design the lateral motion of bipedal walking by means of PTC and realize the dynamic stable motion.

In the medical field and in biotechnology, a new type of micropump that can supply micro liquid flow has urgently been demanded. It is our purpose to develop a type of micropump that has the characteristics of flexibility, driven by a low voltage, good response and safety in body. In this paper, we propose a new prototype model of a micropump using SMA (Shape Memory Alloy) coil actuator as the servo actuator. This paper describes the new structure and the motion mechanism of a micropump using SMA actuator and discusses the possibility of the micropump. This micropump consists of two diffusers (Inlet) as one-way valve, a pump chamber made of elastic tube, and a casing. The overall size of this micropump prototype is 16 mm in diameter and 74 mm in length. Characteristic of the micropump is measured. The experimental results indicate that the micropump has the satisfactory responses, and the proposed micropump is able to make a micro flow and is suitable for the use in medical applications and in biotechnology.

Handling of microorganisms is of great interest in biology and biotechnology. Single cell capture technology has been demonstrated in our previous work with thermal gelation material and micro fluidic devise. This paper extends the system by local flow rate control to stabilize the trap with in-situ fabrication by photo-crosslinkable resin. Target cells are captured by gel and enclosed with the micro-structure. The cells, therefore, are protected from high-speed-channel flow or disturbances. This system succeeds in the separation and continuous culture of yeast cells, reaction and monitoring of the cultured cells stably by fluorescence staining in situ on a chip.

An in vitro soft membranous model of individual human cerebral artery reproduced with visco-elastic behavior, for intravascular neurosurgical simulation, preclinical testing, and testing of medical devices, is presented. The presented arterial model is reproduced with soft visco-elastic tissues, existing around the cerebral artery, in addition to the elastic membranous structure of artery, and constructed based on individual information obtained with medical imaging modality. Its human-like constitution realizes surgical simulation accompanied with realistic feel and visco-elastic structural deformation under actual surgical environment. In this report, we present a production methodology for this anatomically accurate cerebral arterial model. With this methodology, arteries with complicated or high aspect structures are precisely reproducible. We also present a technique to improve its visibility against refraction and reflection that take place on surfaces around arterial model. As the presented arterial model is compatible with current major imaging modalities such as computed tomography (CT), magnetic resonance (MR) and transcranial Doppler (TCD), it should be useful for a wide range of applications, such as hemodynamic study and radiological investigations, as well as surgical simulations.

This paper proposes a control method of vehicle cooperative behavior in an intersection and junction without infrastructures such as a signal system, a road-vehicle communication system, and so on. The vehicle cooperative behavior enables vehicles to pass through an intersection one by one or to interflow at junction one by one without vehicle collision like a weaving and zipping manner. These behaviors are achieved by generating a special-temporal pattern of a reaction diffusion system, where a mutual communication between vehicles is realized only by TVC device. The mutual communication between vehicles can be expressed in the diffusion system of a certain morphogen so that only simple broadcasting communication could be enough for vehicle communication. Van der Pol model is used as one of the reaction diffusion system. Finally, the proposed algorithm for vehicle cooperative behavior is experimentally verified using actual autonomous mobile robots.

We have been developing exoskeleton systems to assist the motion of physically weak persons such as elderly, disabled, and injured persons. The proposed exoskeletons are controlled basically based on the electromyogram (EMG) signals. Even though the EMG signals contain very important information, however, it is not very easy to predict the user's upper-limb motion (elbow and shoulder motion) based on the EMG signals in real-time because of the difficulty in using the EMG signals as the controller input signals. In this paper, we propose a control method for a 3DOF exoskeleton system for human upper-limb motion assist considering the effect of bi-articular muscles.

In this paper we propose a method to insert a long peg into a tandem shallow hole using search trajectory generation without force feedback. Automation of the assembly in a factory progressed in recent years. However the many processes where workers should assemble products by themselves still remain now. We call these processes "difficult assembly". The difficult assembly has the feature that a mating part has a unique shape. The RCC (Remote Center Compliance) is an effective method for assembly, but it is no longer useful on the condition that mating parts are complex. The RCC device has no durability since it is a product made from rubber, in addition a force sensor is expensive. If a robot could accomplish the assembly task without using those devices there is a advantage in terms of expense and durability. In our approach, the manipulator system inserts a long peg into the hole with switching the trajectory generation methods depending on the task condition.

This paper presents a situation-based task selection mechanism which enables a life supporting robot system to perform tasks-based on the user's situation. Stimulated by interactions between robot and user, this mechanism constructs and updates the association between the user's situation and tasks so that the robot could adapt to user's behaviors related to the robot's tasks effectively. For the user adaptation, radial basis function networks (RBFN) and associative learning algorithms are used. The proposed mechanism is applied to CRF3 (character robot face 3) system to prove its feasibility and effectiveness.

Significant research has been conducted in the field of Internet-based teleoperation. However, there is a lack of objective performance measures beyond completion time, which is dependent on several external factors to the system. This paper develops the concept of event-synchronization for supermedia enhanced Internet based teleoperation systems. Supermedia is the term used to refer to the different feedback streams; for example, video, haptic, temperature and others. This performance measure or system property is not affected by external factors; such as, the human operator and the communication characteristics. In addition, the design, which is based on Petri net theory, of systems satisfying this property is detailed. The experimental results obtained using a mobile manipulator bilateral teleoperation system, are given.

This paper proposes a new type of rough terrain vehicle with the interconnected suspension expected to be used to detaining action. This interconnected suspension was proposed and based on posture control of rough terrain vehicle. This suspension has 4 leg-cylinders interconnected and by employing 2 AC motors it can control its posture readily. This suspension makes rough terrain vehicle simple in mechanism. By using this kind of interconnected suspension, the rough terrain vehicle can control its posture smoothly when it walks on rough terrain. In order to compensate the response delay time and improve the control system, we use preview control and the effect was proved in our research. The rough terrain vehicle can control its impact load on every wheel with the interconnected suspension. This kind of suspension can distribute impact load among wheels due to interconnecting every leg-cylinder. In our research, the reduction of impact load on vehicle wheels was proved by experiments. By making good use of the advantages of the interconnected suspension, it is possible that the rough terrain vehicle is actually applied to executing some special tasks such as demining action.

In this paper, we introduce an adaptive sensing method to a landform using a ground reflection of a ground penetrating radar (GPR). When GPR scans a ground surface, an antenna of GPR should be put on a ground as an ideal condition. The farther an antenna is put away from a ground, the shallower the sensing depth becomes, because a ground surface reflects most of the electromagnetic wave radiated by the antenna. Practically an antenna should be manipulated, keeping a small distance from a ground in order to avoid a collision with a ground. Besides, the distance should be controlled so as to observe the ground reflection at a constant position in B-scan image, which is eliminated by a simple algorithm. There are many sensors to measure a ground configuration, but we propose an adaptive sensing which does not require any additional sensors such as laser range finder. In addition, the ground reflection in B-scan image is precisely eliminated by manipulating the sensor head according to GPR sensor information. We show some experimental results to confirm its effectiveness and its performance.

This paper presents an exoskeleton for the assist of forearm motion (elbow flexion-extension and forearm pronationsupination motion) in daily activity and rehabilitation. The exoskeleton is controlled based on the activation patterns of the electromyogram (EMG) signals of the patient's muscles, which directly reflects the motion intention of the patient, in order to realize natural motion assist The sophisticated real-time neurofuzzy control method, in which the effect of a muscle common to both motions is taken into account, is proposed. The proposed control method enables the cooperative motion of elbow and forearm of the patient by learning the muscle activation patterns of each patient. The effectiveness of the proposed method was evaluated by experiment.

A hybrid nanorobotic manipulation system, which is integrated with a nanorobotic manipulator inside a transmission electron microscope (TEM) and nanorobotic manipulators inside a scanning electron microscope (SEM), is presented. The new type of nanomanipulation system has high enough resolution to identify nano-scale objects due to the adoption of a TEM, and efficient and rapid nanomanipulations are realized with wide enough working space of the SEM nanomanipulators. The TEM nanomanipulator has been constructed with 4 multi-layer piezoelectric actuators for driving in 3 translational degrees of freedom (DOFs) and a passively driven 3-DOF sample stage through SEM nanorobotic manipulators to perform relatively complex manipulations whereas to keep compact volume to be installed inside the narrow vacuum chamber of a TEM. To show the effectiveness of the system, the interlayer resistance of a destructively fabricated multi-walled carbon nanotube has been measured inside a SEM whereas the telescoping structure formed by pulling out inner layers from outer layers of the tube is observed inside a TEM.

This paper describes a robotic-head system as a multimodal communication device for human-robot interaction, and the system's potential application in home environments. Most robotic systems for natural user interaction have facial expressions, since facial expressiveness is regarded as a key component to developing personal attachment along with prosodic expressiveness. In the first part of the paper is the description of our robotic head system Character Robot Face (CRF). A deformation approach and a parametric normalization scheme are proposed to produce facial expressions of nonhuman face models with high recognition rates. In the second half of the paper, CRF is endowed with artificial emotions and assigned tasks conceivable in home environments. A coordination mechanism between the robot's mood (an activated emotion) and its task is proposed so that the robot can, by referring to the emotion-task history, select a task depending on its current mood if there is no explicit task command from the user. When the robot performs a task, a particular emotion value gets boosted according to the same emotion-task history so that the emotion is more likely to be activated.

We have been developing robotic exoskeletons to assist motion of physically weak persons such as elderly, disabled, and injured persons. The robotic exoskeleton is controlled basically based on the electromyogram (EMG) signals, since the EMG signals of human muscles are important signals to understand how the user intends to move. Even though the EMG signals contain very important information, however, it is not very easy to predict the user's upper-limb motion (elbow and shoulder motion) based on the EMG signals in real-time because of the difficulty in using the EMG signals as the controller input signals. In this paper, we propose a robotic exoskeleton for human upper-limb motion assist, a hierarchical neuro-fuzzy controller for the robotic exoskeleton, and its adaptation method.

Isolation and separation of the target microbe is quite important. We propose a new touch sensor to get contact information that is needed for separation of the target microbe by the pipette. This sensor is sensitive enough to protect the fragile pipette tip from abrupt collision. Using this sensor, we developed a novel screening system for separation of target microorganisms from the randomly distributed samples on the plate by the local viscosity control of the thermosensitive hydro gel.

Force measurement with pico-Newton (pN) order resolution using a carbon nanotube (CNT) probe, which is calibrated by the electromechanical resonance is presented. Based on the theoretical analysis, a CNT is suitable material for the sensitive force measurement. A CNT probe is constructed by attaching a CNT to the tip of the commercially available atomic force microscope (AFM) cantilever or tungsten needle probe by the electron-beam-induced deposition (EBID) though the nanorobotic manipulators inside a field-emission scanning electron microscope (FE-SEM). In order to attach a CNT quickly and correctly, CNTs are dispersed in ethanol by ultrasonic waves for several hours and oriented by electrophoresis. The elastic moduli of CNTs are calibrated from electromechanical resonance frequency by applied electrostatic forces. We measured pico-Newton order contact forces with a CNT probe, which is constructed with nanorobotic manipulators, by measuring deformation of a CNT probe from FE-SEM images.

A nano laboratory-a prototype nano manufacturing system-is presented, which is composed with a nanorobotic manipulation system with 4 units and 16 degrees-of-freedom (DOFs), a nano fabrication system based on electron-beam-induced deposition (EBID) with an internal or external precursor evaporation reservoir equipped with a thermal field emission electron source or a nanotube cold cathode, and a real-time observation and measurement system based on a field emission scanning electron microscope (FESEM) equipped with 3-4 conventional atomic force microscope (AFM) cantilevers, piezoresistive levers or nanotube probes. Nanotube devices including a mass flow sensor, a linear bearing, and nanotube scissors are fabricated in the nano laboratory.

The coordination of multi-robots is required in many scenarios for efficiency and task completion. Combined with teleoperation capabilities, coordinating robots provide a powerful tool. Add to this the Internet and now it is possible for multi-experts at multi-remote sites to control multi-robots in a coordinated fashion. For this to be feasible there are several hurdles to be crossed including Internet type delays, uncertainties in the environment and uncertainties in the object manipulated. In addition, there is a need to measure and control the quality of tele-coordination. This paper proposes a measure for the quality of tele-coordination, referred to as the coordination index, and details the design procedure that ensures a system performs at a required index. The theory developed was tested by bilaterally tele-coordinating two mobile manipulators via the Internet. The experimental results confirmed the theory presented.

This paper proposes a simplified generation method of regrasping motion. The regrasping motion is designed by evolutional programming (EP) in our conventional study and the obtained regrasping behavior should be adjusted according to some conditions; initial posture and dimensions of a grasping object. However, the designing process of the regrasping motion is off-line because it takes several minutes to find the optimal regrasping strategy by EP. In this paper, we therefore simplified the searching process for regrasping motion in order to apply it in the realtime process. Besides, this simplified generation method is enable to achieve a regrasping motion from arbitrary initial posture because there is no strategy that is previously designed. We show its effectiveness of the simplified generation method with numerical simulations, comparing the performance of the EP-based approach.

This paper discusses practical strategies for transition from a pinching to a power grasping, where a multi-fingered hand mounted on a robotic arm envelops a cylindrical object on a table. When the manipulation system grasps a cylindrical object like a pen on a desk, a complete enveloping is not impossible in the initial configuration. The system firstly pinches the object only with two or three fingers and then grasps it with fingers and a palm after regrasping. In this pinching-grasping transition maneuver, human unconsciously selects proper strategy according to some conditions including object dimensions and initial pinching positions. In this paper we therefore develop six possible strategies for this pinching-grasping transition and then investigate their performances for some objects with various dimensions and various grasping positions, using numerical simulations. Based on their results, a strategy selection algorithm for these conditions is proposed and some experiment results are shown.

Many entertainment and healing robots have been developed. These robots have synthetic emotions so that they select behavior based on their current emotional state. On the contrary conventional robots which have designed to perform repetitive factor or office jobs do not have such emotions. Usually human operators assign tasks in explicit manner using keyboard or voice commands. In this paper we propose a coordination mechanism between robot mood (an activated emotion) and its task. On one hand, referring to the emotion-task history of the mechanism, the robot selects a task depending on its current mood if there is no explicit task command from the user. On the other hand, when it performs a task, a particular emotion gets boosted based on the same emotion-task history so that this emotion is more likely to be activated by external stimuli.

We have been developing exoskeletons (exoskeletal robots) for assisting the motion of physically weak persons such as elderly persons or slightly disabled persons in daily life. In this paper, we propose a 3 DOF exoskeleton and its control system to assist the human upper-limb motion (shoulder joint motion and elbow joint motion) of physically weak persons. The proposed robot automatically assists the human motion mainly based on the skin surface electromyogram (EMG) signals. Fuzzy control has been applied to realize the sophisticated real-time control of the exoskeleton. Experiment has been performed to evaluate the proposed exoskeleton.

A laser micromanipulation is suitable for non contact manipulation of a microscopic object, such as a bacteria and microbe, in the closed space. Here we propose the Synchronized Laser Micromanipulation (SLM) for the trajectory control of the multiple targets by the single laser. We used the laser scanning system for high speed transportation of multiple objects. Condition for secure transportation was derived and verified through the experiment. Using the SLM, we can manipulate multiple microbeads with each designed trajectories. We assembled a band of 4 adhesive microbeads. Both ends are trapped, and it is manipulated by the SLM. It is possible to transport the microbe by the indirect manipulation of the assembled microstructure by the SLM. Experiment results are shown here.

The goal of our research is to achieve a dynamic and skillful motion by a real robot. We have previously developed a brachiation controller that can achieve two kinds of brachiation: overhand and side-hand motions. In this paper, we redesign behavior controllers in order to achieve a stable continuous brachiation without a break. We make the behavior controllers that can be controlled by the angle around a catching bar because the angle is the most dominant parameters of the brachiation motions. In addition, we introduce the action of bending elbow joints in order to realize a pendulum motion and to reduce the impact of the moment of catching a bar. Finally, we show the experimental results that the robot could successfully achieve continuous brachiation.

We present an exoskeleton to assist elbow and forearm motion of physically weak persons such as elderly, injured, or disabled persons. The forearm pronation/supination motion and the elbow flexion/extension motion, which are essential motions for the activities of daily living, are assisted by the proposed exoskeleton. The electromyogram (EMG) signals of muscles in forearm and upper-arm of the exoskeleton's user and the wrist force are also used as input information for the controller. By applying the EMG signals as main input signals to the controller, automatic control can be realized for the physically weak persons without manipulating any equipment. Fuzzy control has been applied to realize the natural and flexible motion assist. Experiment has been performed to evaluate the effectiveness of the proposed exoskeleton.

This paper describes an extension of the flexible transfer system (FTS) with self-reconfigurability of the physical modular configuration. The FTS is a two-dimensional transfer system composed of many modules which transfer a pallet to the neighboring module. A decentralized control which we previously have proposed can generate feasible transfer paths with the adaptability to environmental changes, but the fixed configuration of modules causes the limitation of the adaptability. Therefore, this paper proposes a self-reconfigurable flexible transfer system (SRFTS) and the module reconfiguration method, and addresses the issue of the coevolution of the physical configuration and the control strategy. The self-reconfigurability overcomes the drawback in the conventional FTS, and improves the transfer performance and the fault tolerance. The effectiveness of the proposed method is illustrated by numerical simulations.

Recently robot manipulators have been expected to perform sophisticated tasks such as object manipulation, assembly tasks, or cooperative tasks with human workers. In order to realize these tasks with robot manipulators, it is important to understand the human strategy of object grasping and manipulation. In this study, we have examined how a human being decides the grasping force necessary to manipulate an unknown object in order to apply human object-grasping strategy for robotic systems. Experiments have been performed with several kinds of objects under several kinds of conditions to investigate how much grasping force human subjects generate. Adjustment strategy of human grasping force when the object is manipulated or in contact with an environment is also examined. Neural networks (the desired grasping force planner) that generate the humanlike desired grasping force are then designed for robotic systems. The effectiveness of the proposed desired grasping force planner is evaluated via experiments.

This paper introduces new planning and control methods for supermedia-enhanced real-time telerobotic operations via the Internet. Supermedia is the collection of video, audio, haptic information, temperature, and other sensory feedback. However, when the communication medium used, such as the Internet, introduces random communication time delay, several challenges and difficulties arise. Most importantly, random communication delay causes instability, loss of transparency, and desynchronization in real-time closed-loop telerobotic systems. Due to the complexity and diversity of such systems, the first challenge is to develop a general and efficient modeling and analysis tool. This paper proposes the use of Petri net modeling to capture the concurrency and complexity of Internet-based teleoperation. Combined with the event-based planning and control method, it also provides an efficient analysis and design tool to study the stability, transparency, and synchronization of such systems. In addition, the concepts of event transparency and event synchronization are introduced and analyzed. This modeling and control method has been applied to the design of several supermedia-enhanced Internet-based telerobotic systems, including the bilateral control of mobile robots and mobile manipulators. These systems have been experimentally implemented in three sites test bed consisting of robotic laboratories in the USA, Hong Kong, and Japan. The experimental results have verified the theoretical development and further demonstrated the stability, event transparency, and event synchronization of the systems.

Properties and potential applications of carbon nanotubes are summarized by emphasizing the aspects of nanoelectronics and nanoelectromechanical systems (NEMS). The main technologies for the assembly of nanodevices through nanomanipulations with scanning probe microscopes and nanorobotic manipulators are overviewed, focusing on that of nanotubes. Key techniques for nanoassembly include the preparation of nano building blocks and property characterization of them, the positioning of the building blocks with nanometer-scale resolution, and the connection of them. Nanorobotic manipulations, which are characterized by multiple degrees of freedom (DOFs) with both position and orientation control, independently actuated multiprobes, and a real-time observation system, are one of the most promising technologies for assembling complex nanodevices in three-dimensional space. With a nano laboratory, a prototype nanomanufacturing system based on a 16-DOF nanorobotic manipulation system, the assembly of nanodevices with multiwalled carbon nanotubes are presented. Nanotube-based building blocks are prepared by directly picking up, in situ property characterization, destructive fabrication, and shape modifications. Kinds of nanotube junctions, the fundamental elements for both nanoelectronics and NEMS, are constructed by positioning the building blocks together under the real-time observation with a field-emission scanning electron microscope, connecting them with naturally existing van der Waals forces, electron-beam-induced deposition, or mechanochemical bonding.

Proposes adjusting methods of a regrasping strategy according to position and posture errors of a grasping object. We have already derived a generation algorithm for the regrasping strategy by evolutionary programming. The regrasping strategy however becomes inapplicable when the relative position and posture between a hand and an object is not same as those in numerical simulation. We therefore propose some adjusting methods which can change the intermediate position and posture of a grasping object. This method can avoid the limitation of joint work area and fingertip's slip so that it could extend the tolerable area of the position and posture error. We show its effectiveness for the regrasping motion with numerical simulations and experiments.

We develop exoskeletal robots for the motion support of physically weak persons. In this study, the human elbow motion is assisted by the exoskeletal robot system, since the elbow motion is one of the simplest and the most important motion of human beings in everyday life activities. The angular position and impedance of the exoskeletal robot system are controlled by multiple fuzzy-neuro controllers. The skin surface electromyogram (EMG) signals and the generated wrist force by the human subject during the elbow motion are used as input information of the controller. Since the activation level of working muscles tends to vary with the human subject's arm posture, an intelligent interface that cancels out the effect of posture changes of the human subject's arm is proposed in this paper. The experimental results show the effectiveness of the proposed intelligent interface.

Manufacturing systems have become more and more complex for adapting to various process conditions. Various and numerous sensors are equipped in the system for measuring various states in process. For efficient manufacturing, a sensor fusion method is needed for inferring state which conventional sensors cannot measure. We (2001) have proposed a sensor fusion method with sensor selection based on the reliability of the sensor value and knowledge database for a response to various environmental conditions. In this paper, we propose a sensor selected fusion system with the sensor selection based gating neural network. The gating neural network is stored, which links the neural network for the inference that should be used. Thus, the gating neural network decides the configuration of the neural network from the sensor selection rule and process conditions. For showing the effectiveness, we apply the proposed method to the inference of the surface roughness in the grinding process.

Proposes a controlling method of a mobile robot with structured intelligence. Modular neural networks are applied for action control based on a perceiving-acting cycle of ecological psychology. In the proposed method, the perceptual system and action system restrict each other. Next, we conduct several experiments using a mobile robot we developed. The experimental results show the robot can learn actions based on the perceiving-acting cycle. Finally, we discuss the unit of the action using modular neural networks for robotic systems.

Minimum invasive surgery that supports doctors and reduces patient's physical pain has attracted attention. We consider a new intravascular neurosurgery system. There are two problems in intravascular neurosurgery: one is doctor's exposure to x-ray, and another is the lack of skilled doctors. We developed a remote control system by using a master-slave system to solve these problems. In this paper, we describe the development of a new slave device in the master-slave system and construct the new remote control system of catheter operation with safety. To overcome some of the problems encountered on the previous slave device (2000), we develop a new slave device with a disposable structure employing the mechanism of a mechanical pencil for safe operation.

Reports separation of the target microbe by the laser trapped micro tools for minimum invasion of laser irradiation. The size of a micro tool (MT) is around micrometer. The micro tools are manipulated by the focused lasers under the microscope to manipulate the target microbe. We propose a pinpoint injection method of micro tools at the desired location in the micro chamber, which is filled with liquid. First, we classified the injection method of the micro tools in 4 categories. We employed a new method to install the micro tools inside the micro chamber. We developed a micro tool holding chip to install the micro tools. The micro tools were injected in the micro chamber, and were manipulated successfully by the laser scanning micromanipulator to separate the target microbe. The proposed method is useful for the pinpoint injection of MTs and separation by the indirect micromanipulation.

Nanoassembly of multi-walled carbon nanotubes (MWNTs) in three-dimensional space is realized by positioning these building blocks with nanometer order accuracy, joining them together through van der Waals forces, and fixing them with electron-beam-induced deposition (EBID) or chemical bonds through mechanochemical nanorobotic manipulations. MWNT I-junctions and Y-junctions are constructed. For parallel nanoassembly, the concept of parallel EBID is presented, a MWNT electron-beam emitter is prepared through nanoassembly of MWNTs onto commercially available atomic force microscope (AFM) cantilevers, and the feasibility of using them for parallel EBID is investigated.

We have fabricated a micro touch sensor array. Every touch sensor unit is composed of Ti substrate and PZT thin film. The PZT thin film was synthesized by a hydrothermal method and used as both micro sensor and micro actuator. The micro actuator is driven at the resonant frequency point of the structure. The impedance change can be detected before and after contact by the micro sensor. This micro touch sensor array can be used as the controlling touch sensor pad of a car instead of the conventional capacity type touch pad, because it can resist high temperature. In order to improve the property of the micro touch sensor, the mechanics model, which is used to analyze the relationship between the input voltage and output voltage, was set up. According to cantilever beam theory, the response of the micro touch sensor to electric input has been discussed. Based on the model, the structural characterization of the micro touch sensor has been evaluated. The parameters that affect the output voltage have been analyzed.

This paper explores a human-robot mutual communication system, which human users can either communicate with or use as an information terminal. In particular, we propose the deformation based facial expression system. We also propose a robotic vision system, which changes its visual attention according to the environment. Firstly, the system must have advanced abilities to express their intention by means of making facial expressions, gestures, or speech. Above all, facial expression. Reconsidering the facial action coding system and action unit from the point of what expression of the robot human recognize easily. We propose the deformation based expression system. Secondly, to realize fluent communication between human and robots, we propose a robot vision system changing its gazing communication according to the environment and situation based on visual recognition. We developed an original character robot (CR) and evaluated the proposed methods. Consequently, it was shown that human-robot mutual communication is achievable.

It is our purpose to develop an underwater microrobot that has the characteristics of flexibility, driven by a low voltage, good response and safety in body. We propose a prototype model of an underwater microrobot utilizing an ICPF (ionic conducting polymer film) actuator as the servo actuator to realize swimming motion with 3 DOF. A biomimetic fish-like microrobot using an ICPF actuator as a propulsion tail fin and a buoyancy adjuster for a microrobot swimming structure in water or aqueous medium has been developed. The overall size of the underwater microrobot prototype shaped as a fish is 45mm in length, 10 mm in width and 4 mm in thickness. There is a pair of fins and a buoyancy adjuster. The characteristics of the underwater microrobot is measured by changing the frequency and amplitude of input voltage. The experimental results indicate that the swimming speed of the proposed underwater micro robot can be controlled by changing the frequency of input voltage; the moving direction (upward or downward) can be controlled by changing the amplitude and the frequency of input voltage.

Proposes adjusting methods of a regrasping strategy according to position and posture errors when grasping an object. We have already derived a generation algorithm for the regrasping strategy by evolutionary programming. The regrasping strategy however becomes inapplicable when the relative position and posture between a hand and an object is not same as those in numerical simulation. We therefore propose some adjusting methods which can change the intermediate position and posture when grasping an object. This method can avoid the limitation of joint work area and fingertip slip so that it could extend the tolerable area of the position and posture error. We show its effectiveness for the regrasping motion with numerical simulations and experiments.

We have been developing exoskeletal robots in order to support the motion of physically weak persons such as elderly persons or handicapped persons. In our previous research, the 2-DOF exoskeletal robots for shoulder motion support and its control method have been developed since the shoulder motion is especially important for people to take care of themselves in everyday life. In this paper, we propose intelligent interface, which realizes the fuzzy-neuro controller adjustment in accordance with the human subject's arm posture, in order to effectively control the 2-DOF exoskeletal robot for shoulder motion support. The intelligent interface is realized by applying a neural network. The effectiveness of the proposed intelligent interface of the exoskeletal robot has been evaluated by experiment.

In this paper, we firstly introduce new concept of multi-locomotion robot inspired by an animal and a developed robot "Gorilla Robot II", which can select a better locomotion from biped locomotion, quadruped locomotion and brachiation, according to an environment. We consider "Brachiation" which is one of the most dynamic motions in animal motions. Then we propose an enhanced control method for the robot in order to achieve a brachiation motion, adjusting the timing of local behaviors. We show that the developed robot successfully perform two kinds of brachiation motions.

The exoskeletal robots are expected to support the daily activities of physically weak persons such as elderly persons or handicapped persons in these days. In our previous research, the exoskeletal robots for elbow or shoulder motion support have been developed since the elbow and shoulder motion is especially important for people to perform tasks in everyday life. In this paper, we present a mechanism of the moving center of rotation of the shoulder joint of the exoskeletal robot for human shoulder motion support in order to fit the center of rotation of the robot shoulder joint to that of the physiological human shoulder joint during the shoulder motion. The effectiveness of the proposed mechanism of the robot has been evaluated by experiment.

Recently, micromanipulation for bio-engineering has been developed. The purpose of this research is to develop the minute size knife for the cutting of the minute object such as the cell. In this paper, we report on the microknife that cuts off the object by using ultrasonic vibration of the sharp needle. We applied the multilayer piezoelectric actuator for generating the ultrasonic vibration for cutting. We developed the touch probe sensor for microknife by the PZT thin film which is made by the hydrothermal method. We evaluated the performance of cutting and the touch probe sensor by experiments.

We propose a dome shaped touch sensor unit, which is small and is applicable in high temperature environment. The PZT thin film was made on the half-round Ti substrate, and the electrodes were deposited on its surface to form the sensor and driving actuator. The PZT thin film was made on the curved surface of the substrate by the hydrothermal method. The actuator part is driven by the high frequency voltage at the resonant frequency of 6.2 kHz and the sensing part can detect the impedance change before and after the contact. The sensor works with the low voltage (5 V). It works under the high temperature (over 50/spl deg/C). The structure is simple and easy to miniaturize. This sensor can be used as the control touch-pad of the car instead of the conventional capacitive type computer touch pad, because it can resist high temperature and disturbance from the electrostatic inductance change. The basic property of the sensor is shown.

We develop a new micromanipulation system for anatomical operation of the micro-object such as an embryo, cell, and microbe. The image of the microscope is two-dimensional, so it is hard to manipulate the target in the 3D space. To improve the manipulation work, we proposed a 3D bio-micromanipulation system combined with a virtual reality (VR) space. We propose a 3D object modeling method for presenting 3D visual information to the operator and improve the operation environment. In this system, we still have difficulty in changing the orientation of the microscopic object by manipulating a mechanical manipulator. The bio-aligner proposed is a micro device for the posture control of an object. We develop a 2D bio-aligner by microfabrication. Here we show its fabrication process and a basic rotating experiment with yeast cells.

Multi-walled carbon nanotubes (MWNTs) are manipulated in 3D space with a 10-DOF nanorobotic manipulator, which is actuated with PZTs and Picomotors/sup TM/ (New Focus Inc.) and operated inside a scanning electronic microscope (SEM). The coarse linear resolutions of the manipulator are better than 30 nm (X, Y, Z stages actuated by Picomotors) and the rotary one 2 mrad, while the resolutions of fine motions (actuated by PZTs) are within nano-order. AFM cantilevers are used as the end-effector. Several kinds of manipulations of MWNTs are performed with the developed manipulators with the assistance of dielectrophoresis and van der Waals forces. A single MWNT with estimated dimensions of /spl phi/ 40 nm /spl times/7 /spl mu/m has been picked up on an AFM cantilever. Another /spl phi/ 50 nm /spl times/6 /spl mu/m MWNT is placed between two cantilevers, and still another /spl phi/ 40 nm /spl times/8 /spl mu/m MWNT is bent between a cantilever and sample substrate. Carbon nanotube (CNT) junctions are basic building blocks for more complex devices based on CNTs. A cross-junction was constructed with two MWNTs of dimensions of /spl sim//spl phi/ 40 nm /spl times/6 /spl mu/m and /spl sim//spl phi/ 50 nm /spl times/7 /spl mu/m, and a T-junction was made of two MWNTs with the dimensions of /spl sim//spl phi/ 40 nm /spl times/3 /spl mu/m and /spl sim//spl phi/ 50 nm /spl times/2 /spl mu/m. Force measurements are performed and the flexural rigidity and Young's modulus of an /spl sim//spl phi/ 30 nm /spl times/7 /spl mu/m MWNT are estimated to be 8.641/spl times/10/sup -20/ Nm/sup 2/ and 2.17 TPa respectively. Such manipulations are essential for both the property research of CNTs and the fabrication of CNT-based NEMS.

Robotic operations carried out via the Internet face several challenges and difficulties. These range from human-computer interfacing and human-robot interaction to overcoming random time delay and task synchronization. These limitations are intensified when multi-operators at multisites are collaboratively teleoperating multirobots to achieve a certain task. In this paper, a new modeling and control method for Internet-based cooperative teleoperation is developed. Combining Petri net model and event-based planning and control theory, the new method provides an efficient way to model the concurrence and complexity of the Internet-based cooperative teleoperation. It also provides an efficient analysis tool to study the stability, transparency and synchronization of the system. Furthermore, the new modeling and control method enables us to design an Internet-based cooperative telerobotic system that is reliable, safe and intelligent. This new method has been experimentally implemented in a three site test bed consisting of robotic laboratories in the USA, Hong Kong and Japan. The experimental results have verified the theoretical development and further demonstrated the advantages of the new modeling and control method.

A method for simplification of teaching in robotic assembly is presented. Generally, an assembly task is a process in which a constraint condition between two workpieces changes. There has been much research on teaching an assembly task to a robot system by a model-based approach. However, it takes a lot of time to revise information of models that depend on the task environment when every new task is taught to a robot in these model-based approaches. We propose a method to simplify teaching by taking an approach where a human teaches a task to a robot without giving models of the task environment and task processes. Additionally, we also propose a method to realize robotic assembly that is robust to errors by executing a task as a transition process of a constraint condition. Experimental results show the effectiveness of our method.

The purpose of the study is to build a relaxation system which can control a user's body condition, changing the operation mode and intensity of the massage seat according to the user's current condition. Heart rate is an index of human conditions which can be easily measured, and it has chaotic dynamics. We show relations between the intensity of the massage operation and two indices which express chaotic properties such as correlation dimension and Lyapunov exponent. These data are indispensable for building a feedback loop between the relaxation system and a user.

We deal with exoskeletal robots for human (especially for physically weak people) motion support. In this paper, we propose a fuzzy neurocontrol method for a 1-DOF exoskeletal robot to support the human elbow motion. The proposed controller controls the angular position and impedance of the exoskeletal robot system based on vague biological signals that reflect the human subject's intention. Skin surface electromyogram (EMG) signals and the generated wrist force by the human subject during the elbow motion are used as input information of the controller. Due to the adaptation ability of the fuzzy neurocontrol, the robot is flexible enough to deal with vague biological signals such as the EMG. The experimental results show the effectiveness of the proposed controller.

This paper proposes a new tactile display to present shear deformation to the skin of human finger. For presenting the shear deformation of the finger, we fabricated a three-dimensional moving stage driven by the hydraulic actuators. For presenting different deformation under the condition of the same normal pressure, we used an air suction pad that can suck air. Using this air pad and the hydraulic display system, we performed experiments to present shear deformation. From these experiments, large deformation was achieved under the condition of the same normal pressure.

We developed a new system for random separation of a single microorganism, such as a living cell and a microbe, in a micro fluidic device under the microscope using laser manipulation and microchannel flow. The main flow in the microchannel splits at the exit of the sample chamber. One flow goes to the extraction port with high speed to take out the target. Another flow goes to the drain. The target was transported by laser manipulation from the sample chamber to put on the main flow. Since the force balance of the laser-trapped object is important for stable manipulation of the target, we propose the stagnation point control around the sample chamber exit. Pressure balance was adjusted and the stagnation point was controlled. Some preliminary experiments are conducted to show the effectiveness. The target was trapped by the laser transported to put on the main flow around the split area through the stagnation, and was taken out from the extraction port. Separation time was reduced less than 10 seconds.

We propose a method to acquire a hierarchical behavior controller which is achieved by shifting phase between local behaviors. Complex behavior is hardly obtained using any unsupervised leaning methods, because of enormous search space. In order to reduce the search space, a hierarchical behavior structure is effective. We have previously proposed a hierarchical behavior controller, which consists of two kinds of modules: behavior coordinator and behavior controller. It is applied to the control problem of a seven-link brachiation robot, which moves dynamically from branch to branch like gibbon swinging its body. Numerical simulations demonstrate that the obtained controller can successfully achieve continuous locomotion.

This paper discusses the individuality of agent consisting the group. We study the emotional algorithm evaluating and deciding the statement with artificial emotional model. This paper shows the efficiency of different characteristics of the agent with emotional algorithm, the so-called individuality, and proposes the new traffic signal system, which optimizes the traffic flow by predicting the driver's mind. The proposed traffic signal system applies the emotional algorithm to determine its motion. The emotional algorithm estimates the emotional value based on the emotional functions, which are defined on the emotional space. The emotional space consists of four factors, "happy", "relief", "afraid" and "angry", and provides the emotional states of the system by the value on it. The emotional function aims at the system not to inflict the psychological stress onto the driver. The numerical simulations show the effectiveness of the new emotional algorithm. The DEA simulator, the parameters of which dynamically change by evaluating the congestion of a road, improves the architecture of traffic signals networks.

We have been developing exoskeletal robots in order to realize the human motion support (especially for physically weak people). We propose a 2 DOF exoskeletal robot to support the human shoulder motion. In this exoskeletal robot, the flexion-extension and abduction-adduction motions of the shoulder are supported by activating the arm holder of the robot, which is attached to the upper arm of the human subject, using wires driven by DC motors. A fuzzy controller has been designed to control the robot according to skin surface electromyogram (EMG) signals in which intention of the human subject is reflected. The proposed controller controls the flexion-extension and abduction-adduction motion of the human subject. The effectiveness of the proposed exoskeletal robot has been evaluated by experiment.

This paper proposes a self-organizing control strategy of a signal network for urban traffic flows. The signal network is described using a system of nonlinear oscillators with the nearest neighborhood coupling. The natural frequency, split and coupling constants of the signals are adjusted dynamically according to local information of traffic flows so that the desired network offset patterns are self-organized through mutual entrainment. We provide a preliminary analysis of the coupled oscillator system. Numerical simulations demonstrate the effectiveness of the proposed method under dynamical environmental changes.

In order to help everyday life of physically weak people, we are developing exoskeletal robots for human (especially for physically weak people) motion support. In this paper, we propose a one degree-of-freedom (1 DOF) exoskeletal robot and its control system to support the human elbow motion. The proposed controller controls the angular position and impedance of the exoskeletal robot system based on biological signals that reflect the human subject's intention. The skin surface electromyogram (EMG) signals and the generated wrist force by the human subject during the elbow motion have been fused and used as input information of the controller. In order to make the robot flexible enough to deal with vague biological signal such as EMG, fuzzy neuro control has been applied to the controller. The experimental results show the effectiveness of the proposed exoskeletal robot system.

We have studied the generation of regrasping motion for a four-fingered robot using evolutionary programming (EP). EP has the advantage of finding the set of optimal numerical values but it requires many iterations to find it. The regrasping strategy obtained cannot be applied to other object shapes than those used in the search process. We consider that the regrasping strategy generated by EP should be reused for other sizes of object. We propose an expansion of the method for other sizes of grasped object. We show the effectiveness of the method with experimental results.

Deals with a pet robot with an emotional model. The robot requires several capabilities, such as perceiving, acting, communicating and surviving. Furthermore, it should learn various behaviors through interaction with its owner. This paper focuses on teaching a pet robot tricks or to dance. Basically, the owner can teach these tricks by simple communication based on trial and error. The robot performs the tricks by using a fuzzy controller, and further acquires tricks by a delta rule for online learning and a genetic algorithm for off-line learning. We use "Rag Warrior" as our pet robot. Experimental results show that this robot performs tricks through interaction with its owner.

In grinding process, sensor fusion methods for inferring the surface roughness from online sensing information have received much attention, because it takes a long time to measure the surface roughness during process. We propose a sensor selected fusion system using reliability based on possibility. This method can select sensor information by selection rules of reliability determined by an operator in advance. However, this method cannot select sensor with consideration of the characteristic for each sensor because selection rules for all the sensors are same. In this paper, we propose an acquisition method of selection rules for each sensor using an evolutionary strategy (ES) for the sensor selected fusion system.

The concept of multilevel fuzzy modeling is presented. It is realized as a sequence of k+1 identification procedures of one main fuzzy model and k correction fuzzy models. The resulting multilevel composite fuzzy model CFM is an additive structure of all k+1 models that has the ability to gradually improve the approximation accuracy by adding new correction models. The overall accuracy of this modeling approach highly depends on the identification accuracy of each particular sub-model. The multilevel fuzzy modeling could be used as one possible approach to decreasing the total number of parameters of the fuzzy model by its decomposition into a sequence of simpler fuzzy models. The concept of CFM can be also used with different data sets taken at different times. In such cases the CSM is able to update the overall model behavior according to the new process information still keeping the behavior learned by the previous data set. Finally the multilevel structure of the proposed model could be utilized even with different types of models, not necessarily fuzzy models only. This could be the case when the basic level model is a kind of analytical or stochastic model and the other (correction) level models are fuzzy models learned from the next available data sets. A simple test example in the paper demonstrates the technology of creating as well as the main features of the proposed multilevel fuzzy modeling.

A need has arisen to manipulate a small biological object, such as an embryo, cell, and microbe. Bio-micromanipulation is important for biology and the bioengineering field. However, it is very difficult, since the object is very small, kept in liquid, and observed by an optical microscope. The image of the microscope is two dimensional, so it is hard to manipulate the target in 3D space. The object is fragile, so it is hard to manipulate safely. To improve the manipulation works, the authors propose the viewpoint selection method in VR space, and a bilateral control system to improve manipulation of the micro object under the microscope.

The micro/nano manipulation is the key technology to produce an integrated system as well as to examine the micro/nano world. For example, the micro/nano manipulation is needed for assembly and maintenance of the micro machines and their parts. It is also important for biology and bio-engineering field to explore the micro/nano world. The micro/nano manipulation is classified into the contact type and the non-contact type based on the manipulation method. The manipulation method and system depend on the manipulation environment and the observation system. System design and control methods are completely different depending on the size of the object and the manipulation environment. Here we present highlights on-going research works on the prototyping of the micro/nano manipulation system.

We propose a flexible object manipulation system by a dual manipulator system. Flexible objects like rope or paper have shapes of irregular form, even if the manipulator goes to the same position. We use a flexible object model and vision sensor to recognize flexible object form, and we use a force sensor and vision sensor to confirm the task execution. The dual manipulator system tied a cylindrical object with rope in an experiment.

Proposes an adaptation method for a behavior-based locomotion robot. Utilization of a behavior-based controller makes the controller designing process easier and shorter, because the designer can deal with behavior controllers for simple behaviors independently, and after that can coordinate those behavior controllers in order for a robot to achieve the objective complex behavior. Some problems are still remaining. One is how to adjust the total behavior when the target task or environment is changed. We propose the method to adjust the behavior coordinator against some changes. This method adjusts the activation level of each behavior controller for the changes in fewer trials. It is applied to real brachiation robot control. The brachiation robot has a redundant mechanism to locomote from branch to branch like a long-armed ape.

The control of multi-fingered robot hands has been the subject of interest. To manipulate some object with regrasping motion, there are many parameters to be determined; the grasping points, grasping forces, regrasping phases, finger allocation and so on. It is difficult to optimize such manipulation parameters for achieving effective manipulation. We propose a generation method of regrasping motion for a four-fingered robot hand using evolutionary programming (EP). In this case, EP determines not only finger motions, but also rotation of the target object in order to increase its manipulability. In manipulating an object like a rectangular solid, it is very important to change the object directions and to grasp another face according to the task progress because the grasping faces tend to be limited to only two. The evolutionary optimization method is generally able to find optimal solutions without a supervisor after much iteration, which makes it almost impractical to apply a real robot directly. Therefore we control the real robot hand with an optimal controller that has been generated in computer simulations. We show the effectiveness of the proposed acquisition method for the regrasping motion with experimental results.

Addresses generation of observation behaviors considering various combinations of robotic units. Toward the recognition of group robots, integration of sensing information among robots and autonomous positioning for acquiring better sensing information are required. In the paper, an architecture of recognition and integration based on mappings which are obtained through learning is proposed and a method of autonomous positioning for acquiring better sensing information is also proposed. The results of numerical simulation suggest that robots are capable of generating observation behaviors in order to decrease sensing errors.

This paper presents an effective force control method in which multiple fuzzy-neuro force controllers are suitably and automatically combined with a proper rate in accordance with the unknown dynamics of an environment. The optimal combination rate of the fuzzy-neuro force controllers according to the environment dynamics is defined online by a neural network which is off-line trained with genetic algorithms. The effectiveness of the proposed method has been evaluated by computer simulation.

We report on a control strategy for the "leap" problem arising from an ape's fast brachiation when the next branch is far out of reach and the task involves a significant component of free flight as well as swing motion. In the swing phase, good regulation of velocity and angular momentum for lift-off to aim at the target bar is required. In the flight phase, control of the posture and rotation of the body is important to catch the bar. We propose a control strategy to achieve such a dynamic maneuver for a two degrees of freedom brachiating robot. Numerical simulations suggest that the proposed strategy achieves the desired leaping maneuver.

A parallel beam structure has many significant features, as follows. (i) The tip moves in parallel at the end. (ii) This structure converts a small displacement into a concentrated large strain. (iii) Each unit doesn't interfere with the other units by piling up structures. (iv) The lateral rigidity is high. We propose this structure for a piezoelectric vibrating gyroscope (angular rate sensor), and detected angular rate using this gyroscope. In this paper is shown the method for super sensitizing by bringing two resonance frequencies (drive resonance frequency and sensing resonance frequency) close together. Then we propose the suppression method of the mechanical coupling that arises by bringing two resonance frequencies close. From this result, this structure suits for the gyroscope. Experimental results are shown.

This paper deals with a multi-objective behavior coordinate for a mobile robot using fuzzy control and neural network. A task given to a mobile robot includes various objectives such as collision avoiding, target tracing, and wall following. We apply fuzzy control for describing each behavior of the robot. However, a behavior might share some fuzzy rules with other behaviors. Therefore, this paper proposes a reconfiguring method for a set of fuzzy rules. The combination of fuzzy rules is updated dynamically by a neural network according to the perceptual information. Furthermore, this paper describes a learning method of the neural network and fuzzy rules based on error functions. Simulation results show that the robot can take multi-objective behavior by the proposed method.

We proposed a new teleoperation method using the bilateral control to improve the operability of the laser scanning micromanipulation of the microobject. We propose indirect non-contact manipulation methods of the microbe. It has been reported that direct irradiation of the laser beam to the microbe may give some damage. This phenomenon depends on the target, wavelength, irradiation time and power of the laser. To avoid this problem, we proposed the indirect manipulation of the target by the laser trapped microtools. As a microtool, we tested a micro bead and Lactobacillus bulgaricus (LB) as a micro-chopsticks and a liposome as a micro capsule. Experimental results on indirect manipulation of the microbe are shown.

The e-world, also known as the Internet, has added a new dimension to many of the traditional concepts in industrial applications and everyday life. The use of robots has dramatically expanded the potential of e-services. Individuals with particular expertise can perform highly accurate and fairly complicated tasks remotely via the Internet. This increase in the human reachability is faced by several obstacles. Reliable and efficient robot facilitated services via the Internet face several challenges. These range from human-computer interfacing and overcoming random time delay to task synchronization and human-robot interaction. These limitations intensify when many operators in many sites are involved. This paper provides new theoretical and experimental results on these challenges. Specifically, multisite cooperative control of an Internet based mobile manipulator is presented. The two main characteristics of this system are Internet based real-time closed loop control and coordinated operation. In addition, it is shown that despite random time delay the stability and synchronization of the system were achieved using event-based control.

The flexible transfer system (FTS) is a self-organizing manufacturing system composed of autonomous transfer modules, which transfer a pallet loaded with machining parts. In the paper the central issue is the improvement of the performance of the FTS. By learning automata (LA), the FTS can generate a quasi-optimal transfer path by self-organization of a multi-layered strategic vector field corresponding to a task, and can also recover the system performance against sudden environmental change, such as the malfunction of some transfer modules or the change of machining task. However, in the case where the FTS is composed of large number of modules, we find that it may not work sufficiently. We suggest an idea to improve the performance in such case, and verify the effectiveness by numerical simulation.

Proposes traffic signal networks, which optimize the traffic flow by estimation of the driver's mind. The proposed simulator applies the emotional algorithm to determine the performance of each traffic signal individually and to avoid the traffic jam around it. The emotional algorithm estimates the emotional value based on the emotional functions, which are defined on the emotional space. The emotional space consists of four factors, "happy" "relief," "afraid" and "angry," and provides the emotional states of the system by the value of it. The emotional function evaluates and imitates the state of driver's mind, and aims at not inflicting psychological stress on the driver. This report proposes the principal architecture of the emotional algorithm and some simulators to use it to decide its performance of the traffic signal system. The numerical simulations clear the effectiveness of the proposed emotional algorithm and the applied system. The learning simulator, of which parameters dynamically change by evaluating the congestion of a road, especially shows the excellent performance. Date environment analysis is a good learning method to optimize the parameters in the emotional algorithm by simulation results.

We are stepping into an aging society rapidly. In that society, it is important that physically weak people are able to take care of themselves. In this paper, we introduce a 1DOF exoskeletal robot to support the elbow motion of physically weak people. Fuzzy control has been applied to control the exoskeletal robot system based on vague biological signals that reflect the human subject's intention. Skin surface electromyogram (EMG) signals and the generated force by the human subject's wrist during the human elbow motion have been used as input information of the fuzzy controller.

The authors propose an adaptation and learning algorithm to adjust behavior coordinator against small changes of the objective task or a new one. This method measures the relation between the each local behavior and the global behavior, and then determines the direction of change of the activation values from the behavior coordinator based on the measurements. The monkey-type locomotion robot, Brachiator III has 13 links and 12 joints and is able move like a real ape in a three-dimensional space. The controller is designed for a primitive case. The proposed algorithm is used when the branch interval is changed and when continuous locomotion is desired. We show the effectiveness of the proposed algorithm through experiments using Brachiator III.

This article deals with an operational assistance system for a rough terrain crane. The operation of rough terrain cranes is very difficult because of the complexity of the control system, the swing of payload, and the difficulty of controlling an underactuated system. We propose an operational assistance system for performance improvement based on an interactive adaptation interface. The system does not carry out automatic control directly. It provides information which is useful for the operator to operate more efficiently and safely. We propose a haptic display for swing suppression of a payload. Some experiments on a VR crane simulator have been carried out and show the effectiveness of the proposed system.

We propose an alternative control algorithm for a scaled telemanipulation system using the task-oriented virtual tool dynamics. The aim of the proposed virtual tool approach is to realize the ideal relationship for the human-oriented collaboration between a human operator and a controlled robot in a human-robot environment system. In the proposed cooperative system, a telemanipulator is controlled so that it has semi-autonomous virtual tool dynamics designed appropriately for a given task. It assists a human operator semi-autonomously during the task as if it were a real mechanical tool and improves the maneuverability and the efficiency in the teleoperation. The stability is analyzed based on the passivity of the resultant system, and the total stability is guaranteed for a human operator and a passive environment with unknown dynamics. The algorithm is experimentally applied to a telemanipulator. The results illustrate the validity of the system.

We report on our empirical studies of a new controller for a two-link brachiating robot. Motivated by the pendulum-like motion of an ape's brachiation, we encode this task as the output of a "target dynamical system". Numerical simulations indicate that the resulting controller solves a number of brachiation problems that we term the "ladder", "swing-up", and "rope" problems. Preliminary analysis provides some explanation for this success. The proposed controller is implemented on a physical system in our laboratory. The robot achieves behaviors including "swing locomotion" and "swing up" and is capable of continuous locomotion over several rungs of a ladder. We discuss a number of formal questions whose answers will be required to gain a full understanding of the strengths and weaknesses of this approach.

The control of multi-fingered robot hands has been the subject of recent interest. To manipulate some object with it, it is necessary to determine the contact points and grasping forces at the fingertips, but it is difficult to optimize such manipulation parameters for performing effective manipulation. In this paper, we propose an acquisition method for re-grasping motion for a four-fingered robot hand using evolutionary programming (EP). In this case, EP determines not only when and where the fingers are moved, but also which finger is operated at the next contact point according to the attitude changes of object grasping with the grasping stability. Evolutionary programming is generally able to find an optimal solution without a supervisor after much iteration, which is almost impractical using a real robot. Therefore we control the real robot hand with the optimal controller that has been obtained in computer simulations. We show the effectiveness of the proposed acquisition method for the re-grasping motion with experimental results.

The paper deals with a genetic algorithm for acquiring adaptive behaviors of a fuzzy based mobile robot. If its environmental state is stable or fixed, the behaviors of the robot can be optimized by conventional genetic algorithms. Otherwise, the behavior should be tuned by adaptation and learning according to the change of its environment. However, it is difficult for the robot to maintain behaviors suitable to various environmental states in the dynamic environment. Therefore, the paper proposes a genetic algorithm based on the perceived information about the dynamic environment, which is called a perception based genetic algorithm. We apply the proposed method to collision avoidance behaviors of the mobile robot in a dynamic environment. Furthermore, we conduct several computer simulations. Simulation results show that the proposed method can maintain various behaviors according to environmental changes.

We have previously developed a navigation system for an autonomous mobile robot. It can find the landmarks on the ceiling for navigation. However, when the robot fails to recognize a landmark, the robot can not calculate the self-position. So, the robot has to prepare for the behavior of error recovery. But an error that is not able to recover may occur. In such a case, the robot needs to relocate the self-position. In this paper, we define global matching as the behavior that is able to relocate the self-position and propose to use this module for the error recovery in HALAS (hierarchical adaptive and learning architecture system) that we have proposed as a hierarchical system.

It is important to manipulate a biological small object, such as a cell and embryo. Three-dimensional high speed micromanipulation is needed as a fundamental technology for biology and bio-engineering application. In this paper, we focus on the contact type micromanipulation in the liquid. We designed and made a contact type micromanipulation system which has a 3-DOF narrow range positioning system on a 3-DOF wide range positioning system. We developed a micro tri-axial force sensor which can be installed near the tip of the end effector. Performance of this micro-force sensor is presented.

We propose a searching method of the grasping and manipulating an object in the 3D space by using a four-fingered robot hand, which is applicable to the real robot hand. To manipulate an object, it needs to teach contact points and forces of fingertip, but it is difficult to optimize each parameter for natural grasping. This paper shows the manipulation using evolutionary programming (EP) to optimize the motion of the fingers. In this case, EP determines not only when and where the fingers are moved, but also which finger is operated to the next contact point as the grasping attitude is changed. Moreover, the coding of individual is unique, which makes it easy to optimize the parameter. The result examines the effective in computer simulation in this paper but it would be applicable to a real robot hand.

We present the design of our small robot MARS (micro autonomous robotic system) and basic experiments of group behavior pattern. MARS is small mobile autonomous robot. The robot has sensors, battery and infrared light communication device. In addition, the robot can get programs from the host computer (programmable). We focus on group behavior design (cooperation, competition coordination etc.) to use real robot MARS and we try to realize the phase change of the group behavior pattern. One of our ultimate dream is designing life-like robotics systems, such as ant or fish societies.

This paper proposes a flexible transfer system (FTS) as one of the self-organizing manufacturing systems. The FTS is composed of autonomous robotic modules, which transfer a palette carrying an object. Through the self-organization of a multilayer strategic vector field corresponding to a task, the FTS can generate quasi-optimal transfer path in fully distributed way. We apply the learning automata for path generation algorithm. Simulation is conducted to evaluate the basic performance of the system and the results show the feasibility of application. Also, the developed hardware is explained.

We propose a type of capsule micropump using an ICPF (ionic conducting polymer film) actuator as the servo actuator. This micropump consists of two active one-way valves which make use of the same ICPF actuator, and a tank. The overall size of this micropump prototype is 13 mm in diameter and 23 mm in length. The actuating mechanism is as follows. (1) The ICPF actuator as the diaphragm is bent into anode side by application of electricity. Then the volume of the pump chamber increases, resulting in the inflow of liquid from the tank to the chamber. By changing the current direction, the volume of the pump chamber decreases, resulting the liquid flow from the chamber to the outlet. (3) The ICPF actuator is applied with a sine voltage, the micropump provides liquid flow from the tank to the outlet. A characteristic of the micropump is measured. The experimental results indicate that the micropump has satisfactory responses.

Complex behavior is difficult to obtain using an unsupervised leaning method because of the enormous search space required. In this paper, we propose the hierarchical behavior controller which consists of three types of modules: behavior coordinator, behavior controller and feedback controller. We also propose a new learning algorithm for the behavior coordinator and the behavior controller that consists of some sub-coordinators and some sub-controllers, respectively. This algorithm selects a deficient one by evaluating each sub-coordinator or sub-controller using multiple regression analysis based on previously obtained evaluation values. This can reduce the search area and the learning times by avoiding the necessity of trying to tune good sub-coordinators or sub-controllers. The hierarchical behavior controller is applied to the problem of controlling a seven-link brachiation robot, which moves dynamically from branch to branch like gibbon swinging its body.

Vibration control for flexible structures has been studied by many researchers. We also have proposed decentralized vibration control for flexible structures by decoupling the mode quantities of other links. However if the modeling errors exist in the control system, the performance of the decoupling control goes down since the control method is based on the mathematical model. In this paper, in order to consider the modeling errors, adaptive control based on a neural network is applied to the vibration control of a flexible multi-link system. And by considering the axial forces in modeling, it is found that the modal dynamics is given as a nonlinear system. The effectiveness of the proposed control method is shown by the simulations of a 5-link robotic arm.

In this paper, an effective control policy for robot contact tasks with an unknown environment is proposed using fuzzy-neural techniques. In this control policy, a neural network is applied to classify the unknown environment based on its dynamic response and then fuzzy selector selects the suitable fuzzy neural force controllers. The selected fuzzy neural force controllers are able to realize the desired contact force precisely using their online adaptation ability. The fuzzy selection of controllers realize force control with the environment whose suitable fuzzy neural force controller is not prepared. The effectiveness of the proposed method is evaluated by experiment with a 2-DOF planar robot manipulator.

Robotic or manufacturing systems become more and more complex for adapting to various environmental conditions. In these systems, sensor fusion methods for estimating states of a system from multiple sensor information have received much attention. Also, it is necessary to select the sensor information for adapting to various situations flexibly. In these days, various methods of fusing multiple information have been proposed so far, but these methods cannot select the sensor information. We propose a sensor selected fusion system using a recurrent neural network. The sensor selection method is based on the production system, considering the reliability calculated by the possibility measure. The effectiveness of the proposed method is shown through a simulation of a mobile robot.

There are many researches about the motion planning problem. In this field, main research is to generate the motion for specific robot and task without the previously acquired motions. We consider the motion planning by reusing knowledge. It is our object to realize the hierarchical knowledge with reusing. In this paper, we adopt tree-based representation for expressing the knowledge of the motion and adopt genetic programming as a learning method. We construct the motion planning system using the hierarchical knowledge. We apply the proposed method to the six legged locomotion robot to show its availability.

We have previously developed a brachiation controller that allows a two degree of freedom robot to swing from hand-hold to hand-hold on a horizontal ladder with evenly space rungs as well as swing up from a suspended posture using a "target dynamics" controller. In this paper, we extend this class of algorithms to handle the much more natural problem of locomotion over irregularly spaced hand-holds. Numerical simulations and laboratory experiments illustrate the effectiveness of this generalization.

A parallel beam structure has many significant features, as follows: (i) the tip moves in parallel at the end; (ii) this structure converts a small displacement into a large strain; and (iii) when piling up this structure, each unit doesn't interfere with the other units. We used this structure for a piezoelectric vibrating gyroscope (angular rate sensor), and detected angular rate using this gyroscope. In the paper, we analyze features of the parallel beam structure by the finite element method. We show that the resonance frequency of the drive unit and sensor unit can be easily adjusted by changing the mass at the tip. From this result, this structure suits the gyroscope.

We have proposed a force display method to improve safety and operativity in a teleoperation system for intravascular neurosurgery. This method consists of two parts. One is improvement of operator's feeling of force feedback by displaying two force sensors' information. The another one is variable impedance characterization, which changes the impedance parameters of the master arm dynamically by reflecting the situation of the slave side. We present some experimental results of this force display method and show the effectiveness of this method.

It is a difficult operation to suppress the swing of round payload of a rough terrain crane. We propose a control rule to assist the operation. The stability by the control rule is confirmed with the Lyapunov stability criterion. We propose an operational assistance method with haptic display based on the rule. The system can adapt the strength of assistance to operator's state using recursive fuzzy inference. Some experiments on a crane simulator are performed and show the effectiveness of the proposed system.

Describes initial experimentations done on three LPC (linear predictive coding) derived feature-based speech models: the LPC-cepstrum, the LSP (line spectral pair) and the postfilter-cepstrum (PFL). A comparative analysis of the topological structures of these models is also given. The structures are basically self-organizing feature maps which accept these models as inputs and after training, used to distinguish between isolated word utterances and speakers. A small database of 5 utterances and 4 speakers is initially used. The performance index of isolated word recognition and speaker identification for all models are calculated based on a hit-and-miss ratio and are also discussed. Experimental results reveal that the three parameters are comparable in performance. The LSP has a slight edge over the other two feature vectors in distinguishing isolated words.

We propose a new methodology for isolation of a microbe by the optical radiation pressure and dielectrophoretic force under the microscope. Our methodology is based on the fact that an arbitrary single microbe can be isolated speedily in a microchannel, even though there are a large number of these microbes in a solution. We show that once the target microbe is trapped at the focal point of the laser manipulator, we can easily realize the non-contact exclusion of a large number of excess microbes immediately by controlling the electric field, while keeping the target at the focal point. To improve the operability of the micromanipulation in solution and to realize high-speed separation, the technique of sequential, precise and non-invasive handling is necessary. We propose a new teleoperation method using bilateral control to improve the operability of micromanipulation. Our method can be extremely useful in the pure cultivation of the targeted microbe and will be a promising method for biologists in discovering a new microbe.

In recent years, reinforcement learning has been used as one of methods for making decisions for autonomous robots. However, the algorithm for learning concludes a parameter, and has a fault that adaptation speed for unknown environment changes, according to the value of the parameter. Because of the fault, the robot with reinforcement learning is often delayed in adapting to environmental change. In this paper, we propose a method to reduce the adaptation delay. Our idea is to make it possible for the robot to know if environmental change has happened. We found that if the robot uses reinforcement learning with two different parameters, the correlation between the reinforcement values lowers due to environmental change. Thus, we use the correlation as an index showing environmental change. The effect is proved through computer simulation.

The flexible transfer system (FTS) is a self-organizing manufacturing system composed of autonomous robotic modules, which transfer a palette carrying machining parts. The central issue is realization of both higher efficiency and flexibility to cope with environmental change, such as a sudden change of machining plan or breakdowns of the modules. Through the self-organization of a multi-layered strategic vector field corresponding to a task, the FTS can generate a quasi-optimal transfer path with learning automata. Also, the optimal planning is attempted by use of genetic algorithms, and is based on the global information on the system. We propose a hybridization method between the distributed and centralized approaches. Simulation is conducted to evaluate the basic system performance and the results show the effectiveness.

We have studied a dynamically reconfigurable robot system which is a model of a multiple robot system. The purpose of our study is the realization and practical use of dynamic reconfiguration, especially in cooperation relations among robots according to task, environment and function. We consider space perception by multiple robots as the basic and important ability for robots to behave in environments. The space perception means the mapping from sensing information of each robot to a common task oriented observation coordinate system given by the designer. In the paper the mapping is acquired through learning using time series sensing information. Self-evaluation of reliability of observation for integration is also reported. We examined the proposed the method by using a task model in a two robots environment and the advantage of dynamic reconfiguration of the observation system is reported.

In the biotechnology field, it is very difficult to manipulate microscopic material through human handling. There is a great need for a new experiment system that is easy to operate. We show a 3D calibration technique for improving positional errors of a glass pipette tip, furnished on a micro-manipulator. We then propose a method of observing the manipulator tip of sub-micron order accuracy using a newly developed lighting method by an optical fiber. We also take account of the influence of the positional error of the z-axis introduced from the optical system. In the last part of the paper, we show the effectiveness of these methods through experiments.

Position/force control is one of the most important and fundamental tasks of robot manipulators. Since the desired position and force required to perform certain tasks are usually designated in the operational space, the control force vector should be given to the end-effector in the operational space. However, friction of each joint of a robot manipulator impedes control accuracy. Therefore, friction should be effectively compensated for in order to realize precise control of robot manipulators. The fuzzy-neuro approach, a combination of fuzzy reasoning and neural networks, has been playing an important role in the control of robots. Applying the fuzzy-neuro approach, learning/adaptation ability and human knowledge can be incorporated into a robot controller. We propose an effective robot manipulator fuzzy-neuro position/force control method in which joint friction is effectively compensated for using adaptive friction models. The effectiveness of the proposed control method was evaluated by experiments.

Friction of each joint of a robot manipulator has to be effectively compensated for in order to realize precise position/force control of robot manipulators. Recently, soft computing techniques (fuzzy reasoning, neural networks, and genetic algorithms) have played an important role in the control of robots. By applying soft computing techniques, learning/adaptation ability and human knowledge can be incorporated into a robot controller. In this paper, we propose a two-stage adaptive robot manipulator position/force control method in which uncertain/unknown dynamics of the environment are compensated for in the task space and joint friction is effectively compensated for in the joint space using soft computing techniques. The effectiveness of the proposed control method was evaluated by experiments.

This paper deals with an ecological model on planar gird of a genetic algorithm based on virus theory of evolution (E-VE-GA). In the E-VE-GA, each individual is placed on a planar grid and genetic operators are performed between neighborhoods. The E-

Provides an overview of the technical articles and features presented in this issue.

This paper deals with a fuzzy-based intelligent robotic system that requires various capabilities normally associated with intelligence. It acquires skills and knowledge through interaction with a dynamic environment. Subsumption architectures, behavior-based artificial intelligence, and behavioral engineering for robotic systems have been discussed as new technologies for intelligent robotic systems. This paper proposes a robotic system with "structured intelligence". We focus on a mobile robotic system with a fuzzy controller and propose a sensory network that allows the robot to perceive its environment. An evolutionary approach improves the robot's performance. Furthermore, we discuss the effectiveness of the proposed method through computer simulations of collision avoidance and path-planning problems.

We have previously developed a navigation system for autonomous mobile robots. It can find landmarks on the ceiling to move and work. However, it is impossible to recognize landmarks when the size of landmark is different from the size of template. In such cases, the robot cannot continue to work. Therefore we proposed variable template matching (VTM) that makes it possible to recognize landmarks of different sizes. We realize VTM by using the optimization method called the evolution strategy (ES). The robot can recognize the landmark faster, inferring landmark parameters by binary density projection.

Working robots with agents in the same place has become known by the expansion of the use of a remote control robot. For that reason, we need a safety system which prevents a robot from collision with an agent. An ER-joint realizes high-speed response and force-limiting mechanism at the same time. We apply these properties to an automatic safety mechanism to prevent a collision accident. Then we prove the stability of this system in the case of normal operations by Lyapunov's direct method, and apply the system to a micro-injector in order to show the effectiveness of the mechanism.

Many studies on swarm intelligent systems have been presented. However, analytical treatment on swarm intelligence has not been performed sufficiently, because of difficulties in finding general criteria to evaluate system performance. In this paper, we regard flexibility as one property of the robustness, and evaluate the flexibility of swarm intelligent systems. We propose indexes to evaluate the behavior of swarm intelligent systems, which focus an "flexibility". The proposed indexes provide a way to compare the performance between different swarm intelligent systems. We apply the indexes to evaluate two swarm intelligent systems using computer simulation, and discuss the results.

Piezoelectric materials are used for sensors and actuators. It is difficult to form complicated structures with piezoelectric materials, so the actuators and sensors are simple. Using the hydrothermal method, we can fabricate PZT thin film on a three dimensional titanium substrate. We use this feature for actuators and sensors, and made a new sensor/actuator unit using this method on a parallel beam structure. We propose application examples to a two degrees of freedom actuator, G-sensor, and vibration gyroscope.

It is our purpose to develop an underwater microrobot that has the characteristics of flexibility, driven by a low voltage, good response and safety in body. In this paper, we propose a new prototype model of an underwater microrobot utilizing ionic conducting polymer film (ICPF) actuator as the servo actuator. The fish-like propulsion using ICPF actuator as a propulsion tail fin for a microrobot swimming structure in water or aqueous medium is developed. The overall size of the underwater microrobot prototype shaped as a boat with a pair of fins is 40 mm in length, 10 mm in width and 2 mm in thickness. The characteristic of the underwater microrobot is measured by changing the frequency of input voltage from 0.1 Hz to 5 Hz. The experimental results indicate that the swimming speed of the proposed underwater microrobot can be controlled by changing the frequency of input voltage.

We assume that analyses of collective property is necessary for the establishment of swarm control theory. This paper deals an oscillation as one of the intrinsic collective properties of distributed autonomous robotic systems. The oscillation is a very important property, which influences the entire system performance. Factors which cause the oscillation include an information delay, fluctuation of the system, etc. We analyze the influence of such factors on the oscillation property. In addition, we examine the influence of oscillation on the system performance in terms of task sufficiency and efficiency. The cellular robotic system (CEBOT) is used as a model for the analysis.

Robot manipulators are expected to perform more sophisticated tasks under unlimited environment. In order to realize these tasks, the robot manipulators have to be flexible enough to work in an unknown environment. In this paper, we propose an effective adaptive neural network feedback controller for hybrid position/force control of robot manipulators for an unknown environment by applying new types of neurons which possess visco-elastic properties. The unexpected overshooting and oscillation caused by the unknown and/or unmodeled dynamics of a robot manipulator and an environment can be decreased efficiently by the proposed visco-elastic neurons. The effectiveness of the proposed visco-elastic neural network controllers is evaluated by simulation with the model of a 3-DOF direct-drive planar robot manipulator.

We propose a novel methodology on high throughput screening of microbes. We have developed a prototype of microchannel system for high throughput screening of Escherichia coli. Experimental demonstration of noncontact transportation and manipulation of Escherichia coli by dielectrophoretic force and radiation pressure of laser tweezers has been carried out with laser manipulator system. We discussed the basic strategies to improve the working efficiency and the operability of the micromanipulation and presented a new direction in this field. In experiments, we show that transportation and separation of Escherichia coli with electric field and optical radiation pressure is feasible in the future practical application for the high throughput screening of microbes.

We report on our recent empirical success in the study of a two-link brachiating robot. The "target dynamics" controller developed in our previous work (1997) is implemented on a physical system in our laboratory. The swing locomotion and swing-up behavior of the robot as well as continuous locomotion have been successfully attained. The experimental results illustrate the effectiveness of our control strategy.

A catheter is one of the medical tools for intravascular neurosurgeries. However, to control a catheter in narrow and complex blood vessels is a very difficult task, so there are not many surgeons who can operate a catheter appropriately. Moreover, these surgeons are exposed to X-ray radiation when they perform the operation. A solution to these problems is a telesurgery system. There are, however, some problems in telesurgery system. In this paper, we focus on the problem of operativity involved in a teleoperation system, and propose a new control strategy to display forces which are measured between a slave arm and the environment based on the variable impedance characterization of the master arm.

We propose a technique of grasping and manipulating an object in three-dimensional space by using a four-fingered robot hand, which is applicable to a real robot hand. In our approach, we select the condition of the passive closure as grasping form with an object by the robot hand, and then simplify the necessities for grasping using passive closure. We move the object in parallel motion from that grasping condition by using the slip. Furthermore, we show the new four-fingered robot hand with tension-difference type torque sensors and characteristics. By using this way, for some objects with different shapes, we carry out experiments with this robot hand in practice. Last of all, we verify the proposed method and examine the result.

This paper proposes a system, which manages both efficiency and flexibility in the manufacturing system. It has been considered that an autonomous distributed system is superior to a centralized system in terms of fail-proof expansion, load dispersion, flexibility, and the possibility of the evolution. However, it is difficult to manage both efficiency and flexibility according to conventional method in an autonomous distributed system. To solve the problem, we propose a method. The method is that the carrier organizes the whole number of the carrier in the system, according to the volume of the task and the complexity of it. And we evaluate the proposed method of self-organizing behavior by a multi-AGV autonomous system in the quantitative dynamic environment. It shown that the system has higher efficiency in this system than in the centralized system with self-organization in the quantitative dynamic environment.

In this paper, we propose a new method for reconstructing the shape of objects by multiple vision modules. This proposed method uses the stereo vision module and the shape-from-shading module. In stereo vision module, the conjugate pair of edge pixels is determined by structural analysis and the height is calculated by the triangulation. In shape-from-shading module, we use the Phong model (1975) as the reflectivity function and identify the reflectivity function by evolutionary programming. Then, we estimate the normal vector of pixels. An important feature of our shape reconstruction is that these modules complement insufficient information each other. We show the simulated result for reconstructing the shape of simulated objects.

Intelligent systems are required in knowledge engineering, computer science, mechatronics and robotics. This paper discusses the machine (system) intelligence from the viewpoints of adaptation, learning and evolution of living things. Next, this paper introduces computational intelligence including neural network, fuzzy system, and genetic algorithm. Finally, this paper discusses structured intelligence integrating intuitive and logical inferences, planning, and learning.

Deals with fuzzy scheduling problems including a path planning problem. We have proposed self-organizing manufacturing systems which are composed of autonomous modules. Each module decides output through the interaction with other modules, but the module does not share complete information concerning other modules. The manufacturing procedure can be divided into the sequence of three modules: tool locating module, scheduling module, and path planning module. We first solve the scheduling problem where the processing time is fuzzy. We solve the fuzzy scheduling problem by a genetic algorithm. After preplanning, the path planning module transports materials and products. Based on the processing time, the schedule module updates fuzzy processing time. We discuss the effectiveness of the proposed method through the computer simulation results.

We present a vision based navigation system which has an error recovery function for an autonomous mobile robot. A misrecognition of landmark causes the robot to mislocate itself. When this happens, the robot is unable to perform its primary objective. In order to solve this kind of problem, we have proposed a hierarchical control architecture "HALAS" (hierarchical adaptive and learning architecture system). This consists of some modules which are arranged hierarchically and each module means a single function of this robot. When one module fails in its aim, the upper module detects the error and recovers from it using other useful information from its knowledge data base. We show experimentally that the robot gets a higher reliability in autonomous mobility because the map correspondence module finds the error which has been caused by an anemo perception module (landmark recognition module) and it corrects the error utilizing its map information.

Micro manipulation is required for assembly and maintenance of micro machines and their parts. In this paper, we propose a new pick up and release method for micromanipulation. The proposed method utilizes pressure change based on temperature change inside the micro holes made on the end-effector surface. In order to pick up the micro object, the end-effector temperature is increased to exceed room temperature before touching the object. After contact with the object, its temperature is decreased and negative pressure is generated inside the micro holes to pick it up. To release it, the end-effector temperature is increased again. This method realizes quick response due to its scale advantage as long as it is miniaturized in micro order. We made a prototype end-effector by Si surface micromachining. We analyzed the static performance of this end-effector and conducted experiments. Finally, effectiveness of the proposed method is shown.

This paper proposes a control system for the flexible material handling robot. In the past, there has been reported much research work on flexible material handling robot systems. In most of the previous work, control system parameters were treated as fixed. However, they often change due to variation of the flexible payloads. In some cases, control performance is degraded and the production process is terminated in some situations. To deal with these cases, we propose an error detection method and a replanning system. If system parameters change and control performance is degraded, this system detects error by itself and changes control parameters to recover from the error automatically. Some experimental examples are shown to confirm effectiveness of this proposed system.

The purpose of this research is to generate natural motion of the biped locomotion robot like a human walking in various environments. In this paper, we report a method of natural motion generation of a biped locomotion robot. We apply the hierarchical trajectory generation method to generate the trajectory of a biped locomotion robot through energy optimization and aim to generate more natural motion by considering dynamic effect. The hierarchical trajectory generation method consists of two layers, one is the GA layer which minimizes the total energy of all actuators, and the other is the evolutionary programming (EP) layer which optimizes interpolated configuration of a biped locomotion robot. Then we formulate the trajectory generation problem, as a minimizing problem of energy and apply the hierarchical trajectory generation method. Further, we build a biped locomotion robot in trial, which has 13 joints and made of aluminium materials. Finally, we confirm that the calculated natural motion trajectory can be applied successfully to the practical biped locomotion.

The use of a nonlinear context dependent operator based on possibility theory is studied in order to provide a generic fusion mechanism in different parts of the control of a robot in an uncertain, ill-defined environment. Its main interest consists in the definition of a reliability degree for each partial result which may allow a more pertinent adaptive mechanism.

The purpose of this research is to generate natural motion of the biped locomotion robot such as the walking of a human in various environments. In this paper, we propose a method of stable motion generation of a biped locomotion robot. We apply the control of this proposed method with eight force sensors at the soles of the biped locomotion robot. The zero moment point (ZMP) is a well known index of stability in walking robots. ZMP is determined by the configuration of the robots. However, there are many configurations against the ZMP. Because of that, when we use ZMP as the stabilization index, we must select the best configuration in many stability configurations. Then it is a problem of which configurations are selected. In this paper, we solve the problem with recurrent neural networks. In both the single support and double support periods, we calculate the position of ZMP by using values from four force sensors at each sole, and actuation joints and the angles can be determined by recurrent neural networks without ZMP moving out from the supporting area of sole. We employ the recurrent neural networks with genetic algorithms for learning capability and self-adaptive mutation operator. Further, we build a biped locomotion robot in trial, which has 13 joints and verified that the calculated stable motion trajectory can be successfully applied to the practical biped locomotion.

In this paper, we propose a new prototype model of a micro pump using an ICPF (ionic conducting polymer film) actuator as the servo actuator. This micro pump consists of two one-way valves that make use of the same ICPF actuator. The overall size of this micro pump prototype is 12 mm in diameter and 20 mm in length. The actuating mechanism is as follows. (1) The ICPF actuator as the diaphragm is bent into the anode side by application of electricity. Then the volume of the pump chamber increases, resulting in the inflow of liquid from the inlet to the chamber. (2) By changing the current direction, the volume of the pump chamber decreases, resulting in liquid flow from the chamber to the outlet. (3) The ICPF actuator is put on a sine voltage, the micro pump provides liquid flow from the inlet to the outlet. The characteristics of the micro pump are measured. The experimental results indicate that the micro pump has satisfactory responses.

This paper deals with an application of a virus-evolutionary genetic algorithm (VEGA) to hierarchical trajectory planning of a redundant manipulator. The hierarchical trajectory planning is composed of a trajectory generator and position generator. The position generator generates collision-free intermediate positions of the redundant manipulator. The trajectory generator generates a collision-free trajectory based on some intermediate positions sent from the position generator. To generate a collision-free trajectory of the redundant manipulator, the VEGA is applied to the hierarchical trajectory planning only based on forward kinematics. The VEGA realizes horizontal propagation and vertical inheritance of genetic information in a population of candidate solutions. The main operator of the VEGA is a reverse transcription operator, which plays the roles of a crossover and selection simultaneously. In this paper, self-adaptive mutation is applied to the VEGA for local search of trajectory planning to obtain higher performance and the quick solution. Simulation results of the hierarchical trajectory planning show that the VEGA can generate a collision-free trajectory.

In this paper, we propose a new algorithm to control a distributed autonomous robotic system under dynamically changing environment based on immunological interaction between robots. Our algorithm can organize the robot population for dynamically changing multiple works. At first, we designed a control architecture for a multiple robotic system based on B-cell (which is main agent of immune system) interaction. Immune system has various kinds of B-cells, and B-cell interaction can organize its population balance against dynamically changing environment. We set the analogy between distributed autonomous robotic system and biological immune system. We verified the performance of our algorithm by computer simulation. As a simulation example there is considered the transportation of multiple objects to multiple locations against a deadline, with time-varying demand.

We propose a new methodology on noncontact transportation of DNA molecules by dielectrophoretic force together with the micro DNA flow system. We utilize the conformational transition in the higher order structure of DNA for transportation. We have designed a simple micro electrode-flow system. Experimental demonstrations of DNA transportation in the globule state using dielectrophoretic force and direct observation of the DNA molecule in a nonuniform electric field were carried out with fluorescence microscopy. We discuss the experimental results on the motion of the DNA molecule. We show that transportation of DNA with the state of compacted globule is profitable in the future practical application for the separation of giant DNAs such as the human gene.

We report on our preliminary studies of a new controller for a two-link brachiating robot. Motivated by the pendulum-like motion of an ape's brachiation, we encode this task as the output of a "target dynamical system". Numerical simulations indicate that the resulting controller solves a number of brachiating problems that we term the "ladder", "swing up" and "rope" problems. Preliminary analysis provides some explanation for this success. We discuss a number of formal questions whose answers will be required to gain a full understanding of the strengths and weaknesses of this approach.

Minimum invasive surgery using intravascular surgical tools is getting greater attention in the medical field. This technique allows us to reduce physical pain for patients. For example, a catheter is one of the medical tools for endovascular surgeries. The catheter is frequently used for neurosurgical operations. We propose a new type of force sensor for intravascular neurosurgery. This micro force sensor can be installed on the tip of the catheter. We developed a prototype micro force sensor whose diameter is 1.6 mm and length is 12 mm. Using this micro force sensor, we can measure the contact force between the catheter and blood vessels. It is possible to push the blood vessel wall hard when operators use the catheter. So, to express the contact force between catheter and blood vessels is very important for safe operation. In this paper, we show the structure of the micro force sensor and its characteristics.

We apply the interactive adaptation interface to an operation system. Such a system can adapt to an operator considering the following two points. One is the operator's psychological state and the other is the operator's skill. For adaptation to an operator, the system tunes the time constant of the operation controller by recursive fuzzy inference, and has a "multimodal display" which consists of various types of operational assistance such as visual display, acoustic display, force display, etc. In this paper, we propose many types of operational assistance for a rough terrain crane system. We propose a good control pattern which can suppress the payload's oscillation. The operational assistance becomes more effective by using the control pattern. We made a computer simulation and a joystick for the proposed crane system, and did operational experiments on this simulator. We show the effectiveness of the proposed assistance system for crane operation.

Micromanipulation is important in bio-science and bio-engineering field. In this paper, we propose a new micromanipulation system using a micro bio-jig and electrorheological (ER) joint. First, we propose a micro-fixture device for bio-micromanipulation (bio-jig). Property of the bio-jig is also shown based on the FEM analysis of the electric field. Next, we propose a joint containing the ER fluid (ER joint). We show its application examples to a safety mechanism and variable stiffness type microgripper. We made a prototype of the microgripper with the ER joint. The stiffness of the flexible finger is adjusted by the ER joint. We succeeded in accurate force sensing and fast motion control by controlling the applied voltage to the ER joint.

Problems of information sharing among multi-robots in cellular robotic systems (CEBOT) are described. Information sharing in three aspects (task descriptions, acquiring of robot states and acquiring of environment states) and hierarchical control architecture related to the sharing in three levels are proposed to enhance the efficiency of reasoning and planning for cooperative actions. Then, sensing information sharing related to acquiring of environment states is mainly dealt with, which is refereed to as distributed sensing focussing on sensing information exchange and integration among robots. Through analyzing the nature of distributed sensing, an approach for integration of distributed sensing information, based on evidential reasoning, is proposed. The proposed approach is examined with an application environment map building and maintaining through simulation, and the effectiveness of the distributed sensing approach for acquiring of environment states is shown.

Recently, the research of distributed autonomous robotic system (DARS) has been attracting research interest. The main advantage of DARS is flexibility, comparing with central controlled system. Cellular robotic system (CEBOT) is one of the distributed robotic system which consists of heterogeneous robots and they can change their function by means of structure reconfiguration of robotic units called "cell". In this paper, we consider distributed decision making where system is composed of large group and plural tasks and propose a method of decision making. We applied it to show adaptability of dynamically reconfigurable robotic system.

We propose a new concept of the group robotic system which decides their motion based on the mass psychology. Mass psychology is a subject of behaviour of a crowd of organisms, especially focusing the effect of emotion on the behaviour of a group of organisms. In a group of organisms, the emotion has an effect on their motion and telecommunication between them. We apply this principle of emotion based behaviour to a group robotic system and propose the algorithm to control it using this theory. The simulation results obtained show the effectiveness of the algorithms using emotion.

In this paper, we propose a new method for measuring the shape of objects. The proposed method is based on integrating stereo vision and shape-from-shading with evolutionary programming (EP). In some traditional methods the reflection of objects is treated as diffused reflection. However, the reflection of real objects consists of diffused and specular reflections, thus some methods cannot be applied to real objects. Photometric stereo can be applied to real objects, but this method needs many original images for measuring the shape accurately. The proposed method can apply Phong model to a reflectivity function and measure the shape of the object which have the effect of diffused and specular reflections. The method described using EP identifies the reflectivity function accurately.

Force measurement of the micro objects is very important for micromanipulation. For high accuracy, stiffness of the finger tip can be reduced for force measurement. It is not suitable for manipulation. So we consider to evaluate the stress on the micro structure to measure the force. Force measurement based on stress information has advantages when the structure is miniaturized. This can be shown by the scaling analysis. Hence, we propose a new force measurement and micromanipulation method using the laser Raman spectrophotometer (LRS). We design a micro gripper that employs the proposing force measurement method. We show experimental results of force measurement with the analytical evaluation to explain the effectiveness of the proposed system.

We propose a multimedia tele-surgery system for training, diagnosis, and assistance in surgery. To realize this system, a high speed optical fiber network with asynchronous transfer mode (ATM) is used to provide high quality moving pictures. We designed a new teleoperation system based on ATM, which is different from the conventional one that is based on Ethernet. We built a prototype of the virtual simulator system for the intravascular neurosurgery that consists of a 3D-computer graphics simulator and two types of joysticks. The joysticks are used for the controller and force display of catheter head direction, position, and orientation. A visual assistance method is proposed to assist the operator. We performed teleoperation experiments between Nagoya and Tokyo, about 350 km apart from each other, using high speed optical fiber network, and evaluated the effectiveness of the proposed system.

In this paper, path planning for robots of distributed autonomous robotic system (DARS) in unknown or partially known environment is described based on the distributed sensing. We believe that the basic problem of optimality for motion planning and replanning in unknown or partially known environment is related to the environmental information sensed by robot. Particularly the key to enhance the efficiency of path replanning is to strengthen robot's sensing ability to environment. Considering the characteristics of sensing information in DARS-distributed in time-space-function, we propose that it is practical for each robot in DARS to use (integrate) sensing information of other robots so as to compensate the lack of single robot's sensing ability. Through our simulation experiments, the fact that the efficiency of path planning and replanning for robots of DARS in unknown or partially known environment is evidently raised based on distributed sensing is showed. Approach for planning and replanning in considering the uncertainty of environmental information is also described.

This paper deals with an approach for resolving deadlock conditions in the case of carrying loads by distributed autonomous robotic system such as the cellular robotic system (CEBOT). Deadlock condition occurs when a large number of robots carry loads autonomously. Therefore, we propose to introduce cooperative hand-to-hand motion into the distributed autonomous robotic system to resolve the deadlock conditions using only partial local information. Through the simulation results, we show the effectiveness of hand-to-hand motion and consider influences of environmental characteristics.

A template matching is a popular method for visual recognition. It costs much time to detect the target object. We have applied fuzzy and neural network algorithm to solve this problem. However, the problem to mistake recognizing the target object is not solved. Hence, in this paper, we propose robust visual recognition algorithm for the autonomous robot navigation. The proposing algorithm employs a fuzzy template matching with the target object as well as the similar objects in the environment. As a result, the robot verifies the tentative recognition by comparing the likelihood of plus elements (target objects) with that of minus elements (similar objects). To integrate this algorithm into the robot navigation system, we propose a hierarchical control architecture. The validity of the proposing navigation system is shown with experimental results.

We have proposed a new prototype model of micro catheter with active guide wire that has two bending degrees of freedom using ICPF (ionic conducting polymer film) actuator on its front end as the servo actuator. In this paper, the bending characteristics of the micro active catheter (MAC) have been measured by application of electricity in physiological saline solution. By using simulators (whose conditions are similar to those of a body cavity), we also carried out simulation experiments "in vitro" and the contrast experiments of operability between the proposed catheter and conventional guide wire catheter. The experimental results indicate that the proposed MAC is applicable to intracavity operations.

Position and force controls are important and fundamental tasks of robot manipulators. In order to control position of the robot which simultaneously applies force to the environment, the friction between the robot and the environment has to be compensated. However, the friction force varies according to the applied force to the environment. Therefore, it is difficult to compensate the friction effectively with conventional controllers if we do not know the friction coefficient. Many researches have been done on fuzzy neural control, the combination of neural networks and fuzzy control, in order to make up for each other's weak points. The fuzzy neural control is expected to perform more sophisticated control than conventional control in an unknown environment. In this paper, we propose a new friction compensation method using the fuzzy neural network which contains a specialized neuron for friction compensation and a switch-learning. Simulation has done using a 3DOF planar robot manipulator to confirm the effectiveness of the proposed method.

This paper proposes a control algorithm of a scaled telemanipulation system with communication time delay. With the proposed algorithm, the motion and force relation between the master manipulator and the slave manipulator can be specified freely by using two scaling factors: a motion scaling factor, and a force scaling factor. The scattering transformation is used to guarantee the passivity of the communication system. The stability of the resultant system is analyzed in view of the passivity and the total stability is guaranteed for an operator and a passive environment with unknown dynamics. The proposed method is experimentally applied to a master slave manipulator and the experimental results illustrate the validity of the system.

This paper proposes a force control algorithm for Stewart platform type of parallel link manipulators with velocity controlled hydraulic actuators. First, we design a control scheme for one degree-of-freedom, hydraulic actuator then we extend the control scheme to the parallel link manipulator. The hybrid force/position control scheme for parallel link manipulator is also proposed. The control scheme is designed based on velocity based force control algorithm, so that we can apply it to the parallel link manipulators with velocity controlled hydraulic actuators. The proposed algorithm is applied to the experimental system with six degrees of freedom and the experimental results illustrate the validity of the system.

This paper proposes a population control architecture for a multiple robotic system inspired from biological immune networks. The authors' architecture organizes suitable population balance against dynamic environment independently of any centralized control, while each robot decides its action without a global world model. This group behavior, suitable population balance, is organized as side-effect of the interaction of the individual robots in the world.

In this paper, we propose a new approach to noncontact transportation of DNA molecules by dielectrophoretic force and the idea of the micro DNA flow system. Such system can be made by using microfabrication technology. At first, we designed a simple micro electrode-flow system and carried out experiments. Experimental demonstration of DNA transportation using dielectrophoretic force and direct observation of the DNA molecule in a nonuniform electric field was carried out with fluorescence microscopy. We showed a simple electrode design and the possibility of noncontact transportation of DNA molecules based on micro DNA flow system. In future we consider the possibility of the micro DNA flow system as one of the biomanipulation and automation systems for DNA sequencing.

This paper deals with a modeling and controlling strategy for multi-robot group behavior. While distributed autonomous robot system has advantages in flexibility of the system, it has also difficulties in coordinating the global system behavior as expected by the designer. Our research is to develop an approach in dealing with this problem. Self-organization is a natural principle which can be seen in the dissipative system. We present a hybrid top-down and bottom-up approach and a basic model for coordinating a macro scale group behavior based on the self-organizing mechanism. In particular, we realize the self-organization of temporal behavior patterns.

Micro manipulation is required for assembling and maintenance of micro machines and their parts. As the handling objects are miniaturized, attractive forces such van der Waals force, surface tension force and electrostatic force between micro objects and gripper surface become dominant in the air, and they work as adhesive forces. We cannot neglect such adhesive forces in micro manipulation. Considering the physical phenomena in the micro world, we propose reduction methods of adhesive forces. Surface roughness of the endeffector surface is effective to reduce the van der Waals force. We propose to make micro pyramids on the end-effector surface by micromachining techniques. We designed and made a prototype of the micro gripper with a micro end-effector whose gripping surface is covered with micro pyramids. Experimental results show effectiveness of micro pyramids for reduction of the adhesive force. We also made a semiconductor strain gauge at the end of the micro end-effector surface for force measurement. Both micro pyramids and the integrated piezoresistive force sensor are fabricated on the micro end-effector by the micromachining techniques. Performance of this force sensor is shown.

Distributed autonomous robotic system (DARS) has advantage in flexibility, comparing with central control system. The former researches of DARS mainly deal with the system which is composed of homogenous robots. Cellular robotic system (CEBOT) is one of the distributed robotic system which consists of heterogenous robots and they can change their function by means of connection or disconnection of robotic units called "cell". Functional reconfiguration increases the adaptability against the change of environment further, but it has specific problem concerned with the cost for changing its function. This paper deals with the behavior and the property of system that is composed of functionary reconfigurable robots and we focus on the effectivity of dynamic reconfiguration and the property of system, especially the trade-off between the effectivity of reconfiguration and the cost of reconfiguration through computer simulation by using a model of load transport in the production system.

We propose noncontact sensing and control methods of flexible plate materials handled by a robotic manipulator. A displacement sensor and a force/torque sensor are introduced to measure vibration. Based on the proposed neural network controller, which employs the feedback error learning method as the basic control architecture, this paper deals with the spillover effect to asymptotic convergence of learning. The conditions for asymptotic convergence of feedback error learning method for each trials are obtained. The influence of the vibration modes unmodeled on the conditions for asymptotic convergence is discussed. Based on the results obtained here, we present a new learning method to improve the control performance. The control system consists of a low pass filter and two neural networks. The learning method is to change the learning rate according to the convergence conditions. From simulation results, we show that the tracking performance is improved by using proposed learning method.

Describes the hierarchical control architecture of real mobile robots for Cellular Robotic System Mark-V (CEBOT Mark-V). A parallel processing control system has been adopted, and by adjusting the role of parallel processes standing for the states of independent primitive behaviors, the change of system organization is realized to adapt the redefinition of plural tasks and the variation of environments. The authors propose a method for decision making of a mobile robot's behavior through integrating multiple behavioral processes. The authors define two relation matrices denoting the relationship among the processes: the priority matrix and the interest relation matrix. The matrices are used to adjust the outputs of behavioral processes and optimize the behavior of mobile robots. To obtain the most suitable priority matrix, the authors introduce a learning-adapting algorithm. The results of simulation and experiment with a real CEBOT Mark-V showed the effectiveness of the proposed matrices and learning-adapting algorithm. On the other hand, instead of simply selecting processes for decision making of the robot's behavior, the integration of multiple processes based on the proposed matrices enhanced the control robustness of robot system.

This paper describes a walking method and inclination control experiments of the new omni-directional walking robot, which has six legs and can move in any direction. The mechanism consists of a parallel link mechanism connecting the two frames with three linear actuators. Legs are attached to each frame. The relative position and angle of the two frames are selected arbitrarily in accordance with the length of three actuators, and the posture of it's upper surface are changed with extendable legs. The walking mechanism is composed by combining the two functions. The mechanism and control method of this robot are presented in this paper.

This paper deals with a micro mobile robot in water utilizing a PZT(Pb(Zr,Ti)O/sub 3/) as an actuator. A robot driven by a PZT requires a magnification mechanism and the effects of the resonance to enlarge the displacement of the PZT. In this paper, the authors propose a prototype micro mobile robot which has a new steering mechanism. The robot possesses a pair of legs and each leg has a pair of fins with some angle, which is essential to the improvement of the robot performance. A leg generates force both forward and backward according to frequency because the offset angle between a pair of fins works properly. Therefore, the robot can steer efficiently by combination of both modes. The size of the robot is 32 mm in length and 19 mm in width. This robot has many possible applications, such as small pipelines inspection and use in biomedical fields.

In this paper, we propose a new prototype model of micro-catheter with active guide wire that has two bending degrees of freedom. The design and fabrication methods of this micro active catheters (MAC) are described. Prototype models are 3Fr, 4Fr, 6Fr (1Fr=1/3 mm) in diameter and consist of catheter tube and active guide wire with ionic conducting polymer film actuator on its front end as the servo actuator. The bending characteristics of the MAC have been measured by application of electricity in physiological saline solution. We also modeled this MAC for characteristic evaluation. Experimental results show that the model of the active catheter is reasonable for practical applications. By using simulators (whose conditions are similar to those of a body cavity), we also carried out simulation experiments "in vitro". The experimental results indicate that the proposed MAC is applicable to intracavity operations.

The distributed micro robotic system is a group robotic system, which consists of many micro robots. A mobile robot plays an important role in the distributed micro robotic system. In this paper, the authors propose two types of the micro mobile robot. One is a micro line trace robot that runs along a black line using a pair of photo-sensors. The other is a micro autonomous robotic system constituted by some micro mobile robots controlled by a simple logic. The micro line trace robot consists of a pair of photo-sensors, a pair of electromagnetic actuators and a programmable logic device, but does not include a battery and the interfaces between the controller and actuator. The micro mobile robot constituting the micro autonomous robotic system moves toward the direction of high illumination of light, and includes a battery and interfaces.

A lot of researches have been done on fuzzy-neural control, the combination of neural networks control which has a learning ability from experiments and fuzzy control which has an ability of dealing with human knowledge, in order to make up for each other's weak points. In this paper, fuzzy-neural controller is introduced for robot manipulator contact force control to an unknown environment. A robot manipulator controller, which approaches, contacts and applies force to the environment, is designed using fuzzy logic in order to realize human like control and then modeled as a neural network to adjust membership functions and rules in order to achieve desired contact force control. Error between desired force and measured force and momentum of robot manipulator are used as input signals of the controller. Simulation has done using a 3DOF planar robot manipulator to confirm the effectiveness of the controller for the tasks of approach, contact and force control.

This paper proposes an alternative control algorithm for a tele-manipulator system based on a task-oriented virtual mechanism. For a given task, a task-oriented virtual tool (or a task-oriented virtual mechanism) is designed so that it has the tool dynamics which is used as a tool and assists an operator. Then the authors design a controller for the tele-manipulator system which has the dynamics of the task-oriented tool. Thus, the maneuverability of the system is greatly improved by controlling the tele-manipulator system so that the system behaves as a tool. In this paper, the authors discuss the total stability of the resultant system in view of passivity. Because the system satisfies the passivity condition, the total stability is guaranteed for a passive environment with unknown dynamics by assuming the passivity of a human operator. The proposed control algorithm is experimentally applied to a tele-manipulator system. The experimental results illustrate the validity of the proposed control algorithm.

In this paper, we design a control system so that the dynamic characteristics of the teleoperation system is specified appropriately for the task execution and the extraction of the operator's skill. We define such dynamic characteristics as "reference dynamics" for the task. We consider to design a control algorithm for the master arm manipulating the virtual environment so that the system has the reference dynamics. Then we consider to design a control algorithm for the teleoperation system so that the system has the reference dynamics given to the manipulator of the virtual environment. By designing the control scheme so that the master and slave arm has the same dynamic characteristics, the skill extracted from the operation of the virtual environment would be applied to the real task directly. The proposed system is applied to experimental manipulator system and experimental results illustrate the validity of the system.

We propose a coordinated motion control algorithm of manipulators by which each manipulator is controlled by its own controller in a decentralized way. In this paper, we consider both the manipulation of a single object and assembly of two parts by two arms in coordination. When two arms are manipulating a single object, a follower estimates the desired motion of a leader based on the information from its own force sensor and executes the task in coordination with the leader. An assembly task is described by a motion of a part manipulated by the leader and the relative motion between two parts given to the follower. The relative motion is observed and controlled by a vision sensor attached to the follower and the assembly task is executed independently of the motion of the leader. Experimental results illustrate the proposed system.

Proposes a control algorithm of dual manipulators handling a flexible sheet metal. How to bend a sheet metal and how to manipulate the deformed sheet are discussed in this paper. First the authors derive the relation between the static deformation of the sheet metal and the bending moments exerted on the sheet using Lagrange's equation based on a finite element model of the sheet. The authors then design a control algorithm by which the motion of the manipulated sheet is controlled using the resultant force applied to the sheet and the deformation of the sheet is controlled using the internal force applied to the sheet. Since the rigidity of the deformed sheet is not uniform, that is, the stiffness of the deformed sheet may depend on the direction along which the external force is applied, the authors cannot use the compliance of the flexible sheet for tasks having interactions between the sheet and its environment. The proposed control algorithm is designed so that the apparent impedance of the manipulated sheet metal is specified. The experimental results using industrial robots illustrate the validity of the proposed control system.

This paper presents both the hardware and the software architectures for the multi agent robotic system. For the hardware architecture of the multi agent robotic system, the authors show the programmable MARS (micro autonomous robotic system). This robot can work for one of the agents of the multi agent robotic system. The size of this robot is 20 mm cubic. The authors can rewrite and download any programs by the infrared communication function and the programmable function. For the software architecture of the multi agent system, the authors propose the algorithm which can adapt and generate the swarm strategy in the dynamic environment, based on the biological immune system. The authors adopt the self and non-self recognition network of the immune system in their algorithm.

This paper describes a scheme to enhance adaptability of the multiple robot system using prediction results. The main purpose of this paper is attempt to construct a prediction model, which actively incorporates knowledge of the environment and reflects reasoning results of the conditionally dependent behavior pattern, not only based on the conventional statistical analysis. The presented method will meet the demand and contribute to more efficient decision making in the dynamical environment. Also, some remaining problems are mentioned finally.

Artificial neural network (NN) can be applied to complex dynamical control system. The multilayer neural network with sigmoid function is often used in this field. But this type of NN cannot learn the patterns additionally. It must learn both unlearned patterns and patterns given before. The neural network based on the distance between patterns (NDP) can memorize patterns additionally and recognize unlearned patterns. Adaptive force control using NDP is proposed in this paper. Hierarchical neuromorphic controller is used, in which the higher level NDP detects changes in environments and activates a corresponding lower level controller. Multilayer neural networks are used at the lower level for the control of unknown plant. Hierarchical structure can enlarge the range of the adaptation autonomously, and learn additionally.

Micro manipulation is required for assembling and maintenance works of micro machines and their parts. This paper proposes a handling strategy for micro objects based on micro physics. Attractive forces are modeled and their reduction methods are presented. The authors show experimental results of reducing these forces. Based on the proposed reduction methods, the authors present a new micro manipulation strategy. Grasping of the micro object or press motion is required in some situations, and force information becomes important. The authors propose to use a laser Raman spectrophotometer with single crystal silicon and a strain gauge for the measurement and calibration of the force applied to the micro object. The experimental results of calibrating the force sensing system is presented.

This paper describes a construction mechanism of group behavior on decentralized autonomous robotic systems with cooperation. The decentralized autonomous robotic systems refer to multiple robotic systems including many autonomous robots, such as the cellular robotic system (CEBOT). The CEBOT consists of a number of functional robotic units called "cells". In the research on the CEBOT, same as the decentralized robotic systems, it is one of the most important issues to cooperate among many robots for the group behavior and to coordinate the group behavior, since it is important to organize the behavior of each robot in the multiple robotic systems. In order to organize the behavior in dynamic environment, we proposed a concept of the "self-recognition" for the decision making of the behavior in a robotic group. In addition to the proposed concept, this paper shows the construction mechanism of group behavior using the character of attractor. Based on this idea, we present the behavioral evolution of the group robotic systems.

We propose a vision based navigation system for autonomous mobile robots that recognizes outlets of air conditioning system (anemo) located on the ceiling as landmarks. Because landmarks on the ceiling are not obstructed by other objects, robots can find them easier than landmarks on the floor. To detect the landmark, we applied the fuzzy template matching (FTM) method. Based on FTM, a fuzzy template (FT) is modeled based on the edge information of landmarks in the image. In addition, we use neural network (NN) to detect landmarks quickly. Inputs of NN are the grades of fuzzy memberships and the learned NN directs FT to the landmark in the image. Because FTM does not use image processing, except edge extraction, it does not make processing error and the landmark can be detected precisely. The navigation system can calculate the distance and the angle of the anemo from the map information. As a result, the navigation system can identify the present robot's position and orientation. By the proposed algorithm, precise and fast landmark detection become possible even if the landmark follows the shadow.

We propose a new prototype model of micro-active guide wire catheter that has two bending degrees of freedom. The fabrication methods of this micro-active catheters (MAC) are described. Prototype models are 3Fr, 4Fr, 6Fr (1Fr=1 mm) in diameter and consist of catheter tube and active guide wire with ionic conducting polymer film on its front end as the servo actuator. The bending characteristics of the MAC have been measured by application of electricity in physiological saline solution. By using simulators (whose conditions are similar to those of a body cavity), we carried out simulation experiments "in vitro" and the contrast experiments of operability between the proposed catheter and a conventional guide wire catheter. The experimental results indicate that the proposed MAC is applicable to intracavity operations.

This paper proposes an alternative control algorithm for a scaled telemanipulation system based on a semi-autonomous task-oriented virtual tool. In the algorithm a telemanipulator is controlled so that it has a virtual tool dynamics. The virtual tool dynamics designed appropriately for a given task is to assist an operator as a tool and the operator executes the task easily with the tool. In addition, the motion and force relation between the master and the slave can be specified freely by using two scaling factors; a motion scaling factor and a force scaling factor. The stability of the resultant system is analyzed based on the passivity of the resultant system and the total stability is guaranteed for an operator and a passive environment with unknown dynamics. The proposed algorithm is experimentally applied to a telemanipulator. The experimental results illustrate the validity of the algorithm.

We propose a coordinated motion control algorithm of manipulators, by which each manipulator is controlled by its own controller in a decentralized way. We select a manipulator as a leader and a task is described by the motion of the leader and the motions of the other manipulators relative to the motion of the leader. The latter manipulators are referred to the followers. First we consider the problem of manipulation of a single object by multiple manipulators. In this task, the motion of the object is given to the leader. To execute the task in a decentralized way, we propose an algorithm for each follower to estimate the notion of the leader based on the information from its own force sensor. Using the algorithm, the manipulation of a single object is executed in a decentralized way. We consider the parts-mating problem, next, by two manipulators in coordination. An assembly task is described by the motion of a part manipulated by the leader and the relative motion between two parts given to the follower. The relative motion is observed and controlled by a vision sensor attached to the follower and the assembly task is executed independently of the motion of the leader. Experimental results using two industrial robots will illustrate the validity of the proposed control system.

Proposes a trajectory control method for a flexible plates handling system with unknown parameters and joint friction. First a recurrent neural network (RNN) learns the dynamics model of the flexible plate handled by a robotic manipulator. Next, the authors obtain the feedfoward control input based on the RNN model using the proposed learning control method. The authors applied this repetitive method to both linear system and nonlinear system control. Coulomb friction is considered at the joint as the nonlinear effect. Simulation examples are conducted to show effectiveness of the proposed method.>

In this paper, we propose a new prototype model of serial-parallel type of active micro catheter (MAC) with two bending degrees of freedom. It is 4 Fr, 5 Fr and 6 Fr (1 Fr=1/3 mm) in diameter and consist of 3 active units incorporating SMA wires in lumina as the servo actuator. The bending motion, bending direction and bending angle of the MAC have been measured by application of electricity in air and in physiological saline solution. We also modeled this MAC. Experimental results show that the model of the MAC is reasonable for practical applications. By using simulators (conditions similar to a body cavity), we carried out the simulation experiments of "in vitro" and "in vivo". The experimental results indicate that the proposed MAC is applicable to intracavity operations.>

This paper addresses an optimization method of the group behavior on decentralized autonomous robotic systems. Decentralized autonomous robotic systems refer to multiple robotic systems, such as cellular robotic system (CEBOT). The CEBOT, which has been proposed by the authors, consists of a number of robotic units called cells. In the research on the CEBOT, the same as decentralized robotic systems, the optimization of the behavior of each robot is one of the most important issues, since it is difficult to predict the behavior of the each robot in multiple robotic systems. In order to optimize the behavior in a dynamic environment, the authors propose a concept of self-recognition for the decision making of the behavior in a group. According to the proposed concept, this paper shows the learning and adaptation strategy for the group behavior, and presents some simulation results.>

This paper deals with a micro-mobile robot in water utilizing PZT(Pb(Zr, Ti)O/sub 3/) as an actuator. A robot driven by PZT requires a magnification mechanism and the effects of the resonance condition to enlarge the displacement of the PZT to some extent. In this paper, we show a prototype micro-mobile robot in water (double-fin-fish robot), which possesses a pair of fins and moves them symmetrically. Therefore, the momentum of this robot is canceled and the tendency to move straight ahead is improved. The size of the robot is 50 mm in length. We propose a structure for the magnification mechanism, which is made by the wire cut method. The magnification ratio is 326 geometrically. This robot has many possible applications, such as small pipeline inspections and biomedical fields.>

This paper deals with a criterion to reduce excessive communication in the Cellular Robotic System (CEBOT). While communication plays a significant role in acquiring necessary information for the decision making, we should consider its cost especially in a case that a large number of agents are involved. Therefore, we attempt to achieve the "intelligent communication" that is defined as accumulation of knowledge bringing higher performance and less frequency in the robot communication. For acquiring information through the communication, a probability model is constructed. The decision is presumed based on the model but the risk for that is evaluated as to whether the communication is negligible. We show that there exists correlation between accuracy of the estimate model and communication necessity.>

This paper discusses a framework and the algorithms for a reconfigurable intelligent system, which is capable of "knowledge amplification". The proposed intelligent system consists of many kinds of knowledge sources, which have simple levels of data and intelligence together with some blackboards which dynamically organize a hierarchical structure in order to optimize its own performance index. The system has two strategies for reconfiguration of the system structure: one is "entropy maximum strategy" the other is " entropy minimum strategy". The entropy maximum strategy is used when many kinds of tasks are given to the system. The entropy minimum strategy is applied in cases were the system deals with a few tasks only. This paper addresses the fundamental configuration and algorithms which include these two strategies for reconfiguration. The efficiency of the proposed system is shown by some simulations.>

This paper describes the overall architecture for complex motion learning of practical robotic systems and then proposes a method to extend reinforcement learning to the domain of continuous robot control problem in order to apply it to behavior learning of practical robotic systems. To represent continuous control variables, CMAC is employed for utility networks, and to fully utilize experiences, experience sequences are stored and replayed with priorities. As a testbed, the learning system is applied in simulation to the control of swing amplitude of a two-link brachiation robot which is hardly constrained with dynamics.>

This paper deals with a self-organization of the group of multiple robotic systems, such as the cellular robotic system. Especially, in this paper, the authors present the self-organization of the hierarchical structure of the cellular robotic system as one of the group robotic systems. The structural organization is simulated based on the idea of interdependence between autonomous robots, which is derived from the model of group organization of humans. That is, the groups are organized and any leaders emerge from the interdependence in the individuals. This paper represents simulation results of self-organization of hierarchical structure on the basis of a given task model.>

This paper proposes a method to design a force controller based on frequency characteristics. Generally, force control algorithms are classified into two types, the explicit force control algorithms such as hybrid position/force control and the implicit force control algorithms such as impedance control. The explicit force control algorithms control the contact force directly, while the implicit force control algorithms control the manipulator motion-force relation. Recently, Goldenberg (1992) and others have shown the equivalence of these two types of algorithms. In this paper, we propose a method to design an explicit force controller based on its equivalence to the impedance controller so that the resultant control system has desired frequency characteristics. The method is applied to a manipulator with one-degree-of-freedom and experimental results illustrate the effectiveness of the proposed method.>

This paper describes a predictive decision making strategy for the multiple robotic systems. Although communication plays an important role in the robot system, it tends to be regarded as merely information exchanges by data transmission. However, it is one of the vital intelligent activities in the multiple robot systems. In this paper, we propose a framework of "intelligent communication" which treats communication as an essential part of decision making considering interaction with the other agents. It includes knowledge abstraction from discrete events, intention reasoning and prediction, etc. This paper focuses on the intention reasoning with prediction, and proposes the concept of hierarchical prediction model for its realization. We discuss the advantage of prediction and its difficulty for application to the robot through the simulation results.>

This paper proposes an alternative control scheme for a teleoperation system which consists of a master arm, a slave arm and a virtual environment. For a given task, the operator manipulates a virtual environment and executes the task, a skill for the task is extracted through the manipulation, and the skill is transferred to the remote site to execute the task in real. First, the authors consider the design of a control algorithm for a master arm manipulating the virtual environment so that the system has a given dynamics for the operator and the environment. Then the authors consider the design of a control algorithm for the master-slave system manipulating the real environment so that the system has the same dynamics given to the manipulator of the virtual environment. By designing a control scheme, with which the master arm with a real environment and the master arm with a virtual environment have the same dynamics, the skill extracted from the operation of the virtual environment would be applied to the real task using the slave arm. The proposed control system is applied to an experimental master-slave manipulator and experimental results illustrate the effectiveness of the system.>

This paper proposes a unified coordinated motion control algorithm of manipulators, which is applicable to both manipulation of an object and a parts-mating task. First, the authors consider the manipulation of an object by impedance controlled manipulators; the impedance of each arm is designed so that the apparent impedance of the manipulated object is specified. Then the authors consider the parts-mating problem using the same control algorithm proposed for the manipulation of a single object. The authors propose a method to design the impedance of each arm so that the relative motion of two manipulators has the dynamics of the remote center compliance. The experimental results using two industrial robots illustrate the validity of the proposed control system.>

Some existing production technologies cause environmental deterioration. It becomes a key issue to save and use resources effectively from the view point of environment protection. Therefore, trends of technologies are now changing from improving the productivity to improving the recycling. This paper presents robotic technology for automatic reusable manufacturing that more effective usage of resources than conventional manufacturing. Some examples for aircraft industry will be presented.>

This paper presents a new scheme for intelligent control of robotic manipulators. This scheme is a hierarchically integrated approach to neuromorphic and symbolic control of robotic manipulators. This includes an applied neural network for servo control and knowledge-based approximation. The neural network in the servo control level is based on a numerical manipulation, while the knowledge based part is symbolic manipulation. The knowledge base part develops control strategies symbolically for the servo level. The neural network compensates for vagueness in the control strategies, nonlinearities of the system and uncertainties in its environment using neuromorphic control.

Deals with the improvement of learning speed based on the analysis of the convergence of the feedback error learning method. The authors derive the condition for the asymptotic convergence of the feedback error learning method for each trial. This condition is the relationship between the learning rate and the /spl alpha/ function, which is calculated from the input-output relationship of the system. Using the /spl alpha/ function obtained above, a high-speed learning method for a trajectory control system is obtained. Simulations results are given for the trajectory control of a 1 link robot manipulator in two cases: (1) using a general feedback error learning method and (2) using the proposed high-speed learning method. The simulation results show the effectiveness of the proposed conditions and learning method.

The authors propose a micro mobile robotic system on an air bearing with a cordless optical power supply system. The system consists of a floating robot mounted with a PLZT pyroelectric transducer and an air table with air nozzles and blocks. The robot uses the PLZT element to convert the optical energy to electric energy. Illuminating the PLZT with ultraviolet light generates an electric voltage high enough to drive the robot. To solve the friction problem, the air bearing and air guide system are used. The air system makes it possible for the robot to travel autonomously and to be driven by small force. The experimental results for movement and the capacities of the micro optical mobile robotic system are demonstrated.

Recurrent neural networks have dynamic characteristics and can express functions which depend on time. To apply these neural networks to the memory of robotic motions, i.e., trajectories of manipulators, it is necessary to determine appropriate network interconnection weights. A new learning scheme for recurrent neural networks using a genetic algorithm (GA) is presented and used to determine the interconnection weights. The GA approach is compared with backpropagation through time. Simulations illustrate the performance of the new approach.

Presents a new approach to communication in an autonomous distributed system, focusing on the cellular robotic system (CEBOT). The CEBOT is a self-organizing robotic system composed of a large number of robotic units (cells) with a simple function. In order for cellular robots to implement a task efficiently, cooperation and coordination among cells are of great importance and require efficient communication. Since communication takes place in the process of task execution, it is likely to be intensive and biased by the small number of cells related to the task. This could decrease communication efficiency. To deal with these problems of robot communication, the authors propose demand-based intensive communication (DBIC), and show its effectiveness with simulation and experimental results for the prototype CEBOT Mark IV.

The authors have studied the cellular robotic system (CEBOT) with the aim of realizing a self-organizing robotic system. It can be regarded that CEBOT is one of the multi-agents robotic systems studied by many researchers. It is generally considered that one of the features of the multi-agents robot is that the system can carry out many kinds of tasks under various environments due to coordination among many agents. It is assumed that a group of the agents can get higher performance than an ability of single agent. In this paper, the relation between the resource amount, which implies both hardware and software installed into the system, and system performance is discussed. At first, a new concept called function amplification is proposed and defined, the control law of each agent to achieve the function amplification is secondarily discussed. In the last part of this paper, some simulations are reported and discussed to demonstrate the relation between resource amount and system performance.

This paper proposes an alternative control algorithm for the mechanical system which interferes with both an environment and a human operator (man-machine system). The algorithm is designed so as to control the dynamics of the mechanical system to imitate passive tool dynamics. The proposed control algorithm specifies the human force augmentation ratio and the maneuverability of the system. The stability of the system is guaranteed for the passive environment and the passive human dynamics; the stability of the proposed control system is verified using Popov's hyperstability theorem.

This paper proposes a method to evaluate kinematic structures of a Stewart platform type of manipulator based on the relationship between actuator forces and output forces/moments of the mechanisms. The input/output force analyses proposed so far have been based on the manipulator Jacobian, in which forces and moments are dealt with together. However, it is not natural to deal with both force and moment together, since the force and the moment have different dimensions. The authors analyze manipulators by dealing with the output forces and the output moments independently. They evaluate an output force ellipsoid and an output moment ellipsoid for input force vector whose Euclidean norm is equal to one. The kinematic structure is then evaluated based on the force ellipsoid and the moment ellipsoid of the moving platform. The method is natural and intuitive and is useful for the design of the manipulator kinematic structure.

A new strategy for motion planning of multiple robots as a multi-agent system is proposed. The system has a decentralized configuration. All the robots cannot communicate globally, but some robots can communicate locally and coordinate to avoid conflicts for public resources. In such systems, it is difficult for each robot to plan its motion effectively while considering other robots, because the robots cannot predict the motion of other robots as an unknown environment. Therefore, each robot only determines its motion selfishly while considering a known environment. In the proposed approach, each robot plans its motion while considering the known environment and using empirical knowledge. The robot considers its unknown environment including the other robots in the empirical knowledge. A genetic algorithm is applied to optimize the planning of the motion of each robot. Through iterations, each robot acquires knowledge empirically using fuzzy logic For an illustration, this paper deals with path planning of multiple mobile robots and performs simulations.

The authors propose a neural network (NN) model for pattern recognition which can learn new patterns without losing patterns memorized in the past. This model is called a neural network based on distance between patterns (NDP). The NDP uses the radial basis function (RBF) as the response function in place of the sigmoid function. The response function is a smooth function similar to the Gaussian base function and the probability density function. The response function learns patterns faster than the multilayered perceptron (MLP) as well as other RBF NNs. The most salient architectural feature of the NDP is self-organization by adding nodes in the output layer one by one. The NDP also varies the curve of the response function by tuning the center and the width of the response function, and separates the input space into regions for each category appropriately.

Force control in contact tasks is discussed, and the system stability is proved theoretically using the Lyapunov direct method. A one-degree-of-freedom manipulator representing simple linear manipulators is treated. Some numerical simulations are executed both for the analysis verification and for the discussion of transient responses. As manipulators are mostly designed to do tasks acting on the environment and their home positions are in free space, the tasks naturally include contact. If the motion is fast enough, the interaction becomes collisional, which has up to the present time dominated the speed of the task because the motion at the contact has been controlled very slowly to avoid collision. In this paper, the stability of the motion is proved theoretically, and the contact, or collision, can be controlled with attention to the control law.

In the process of a cooperative search in a distributed robotic system, the local information and local knowledge, as well as the limitation of sensing range and communication range must be considered. The authors present a distributed genetic algorithm with a supplement operation as a method for cooperative searching. The distributed genetic algorithm is a search algorithm modified for a distributed robotic system. As an example of a cooperative search, path planning for configuring the structure of a cellular robot is considered. The cellular robot or cellular robotic system (CEBOT) is a distributed robotic system which consists of a large number of autonomous robotic units called cells. The process of cooperative path planning using the proposed genetic algorithm with communication between the cells is presented. The influence of the local sensing and local communication is considered.

Most of the explicit force control algorithms published so far assume the switching of the control law from position control to force control when a transition occurs from a free motion to a constrained motion, but the ideal switching of the control law is impossible for a rapid transition. Implicit force control algorithms, such as stiffness control, damping control, impedance control, etc., can be applied to both free motion and constrained motion without switching the control law. However, precise force control is difficult, especially with nonrigid environments. The authors propose an alternative force control algorithm for nonrigid environments based on damping control, so that the transition occurs naturally. They model a damping control system with environmental dynamics and design a predictive control algorithm so that the force is precisely controlled when the motion of the robot is constrained. The proposed method is applied to a manipulator with one degree of freedom, and experimental results illustrate the validity of the method.

A tracking problem for controlling the speed and azimuth of a mobile robot driven by two independent wheels is solved by using a fuzzy Gaussian neural network (FGNN) controller. The computed torque control law is first derived to obtain some relationships between the driving torque and the plant output information. To simplify the FGNN controller for the two-input two-output controlled system, a learning controller consisting of two FGNNs based on independent reasoning and a connection net with fixed weights is proposed. The effectiveness of the method is illustrated by performing the simulation of a circular trajectory tracking control.

A primitive approach to the self-organization of the structural configuration of the CEBOT is described. CEBOT consists of a large number of autonomous robotic units called cells. Assuming that there are sufficient cells in the environment to configure the cellular robots, the cells, which have information about a structure, use random walk to search for other cells to configure the structure. Since each cell organizes a cellular module/robot distributively, these cells must cooperate and negotiate to achieve the configuration of the goal structure. The behavior of the cells is examined on the basis of the selfish criterion. The entropy of structure configuration is proposed as an evaluation criterion in the global environment. The simulation represents the influence of the selfish behavior and the sensing range for the configuration of the cellular robots.>

The authors propose a center of gravity control method for a manipulator/vehicle system to ensure that the system cannot fall down. The algorithm controls the tip position of the end effector and the combined center of gravity of the manipulator and the payload. This control algorithm has been applied to a system in which a human cooperates with a robot. The trajectory of the manipulator is given by the operator and the center of gravity is pre-set so that it does not tumble. An experiment was carried out to confirm the effectiveness of this control algorithm for the manipulator/vehicle system.>

The authors propose a genetic knowledge production algorithm (GKPA) for CEBOT, in order to realize a self-organizing and self-evolutionary knowledge system. They propose a new kind of distributed intelligence system which is based on the concept of CEBOT employing the GKPA. This proposed intelligence system has capabilities of learning, reasoning, and self-organizing. This system consists of various kinds of intelligence units called knowledge-cells. As an example of the applications of the self-organizing intelligence, a robotic manipulator capable of learning and reasoning has been made from the CEBOT concept by installing the intelligence system with GKPA in the manipulator. The knowledge acquisition ability of the manipulator is demonstrated by experimental results.>

The authors present a scheme for intelligent control of robotic manipulators. This is a hybrid system of neuromorphic control and symbolic control of a robotic manipulator, including a neural network for the servo control and a knowledge-based approximation. The neural network in the servo control level is for numerical manipulation, while the knowledge-based approximation is for symbolic manipulation. In neuromorphic control, the neural network compensates for the nonlinearity of the system and the uncertainty in the environment. The knowledge base develops the control strategy symbolically for the servo level. This is an analogous control system to the human cerebral control structure.>

The authors consider a grouping issue for a cellular robotic system (CEBOT) with multiple master cells. The CEBOT consists of a large number of autonomous robotic units called cells, that is, the system is one of group robotic systems. To evaluate the grouping effectiveness, the authors use the network energy. They consider each master cell as a coordinator in each sub-network. To evaluate the grouping network, they propose the cross-dependence matrix, which presents the relation between the cells and the task steps depending on a given task. The simulation results present the grouping examples of the cellular network. By describing the grouping issue, the authors also describe the effect for the group structure of an organization or a society.>

This paper presents hierarchical control system for compensation & vibration control of flexible material handling robot using neural network for t he control parameters scheduling and dynamic control. In this paper, compensation control method is classified into two cases; (i) a method based on estimated value of tip position, and (ii) a method based on measured value of tip position. The method (i) is only available for the simple cases (i.e., the deflection is small and the section of the material is unity). In the method (ii), by choosing control parameters properly, it is shown that the compensation & vibration control with small position error is possible. However, it is quite difficult to select proper control parameters for each different payloads so that the control system remains stable. To solve this problem, we propose hierarchical control system. This system has a gain scheduler at the upper level to roughly select proper control parameters for each different materials, and has a neural network controller at the lower level to improve control performance. After designing gain scheduler and neural network controller properly, the system can adapt to improve the response time for the large number of different kinds of materials.

Cellular Robotic SystemCEB0T has been studied to realize a dynamically r econfigurable r obotic system, which can c arry out m any kind of tasks under various environments by the authors. CEBOT consists of a lot of units called cell which has a simple function. To deal with a complex task which can not be carried out by a cell, CEBOT generates various module ,which is composed of some cells. A much complex 5ystem composed of some modules is called structure, which can carry out very complicated tasks. As above mentioned concepts, CEBOT is very similar to a living creature, because tissues and organs are formed by a lot of cells. CEBOT h as to not only create new modules and structures, but also kill some modules and structures, because the number of cells is limited. Therefore it is necessary to study a system which can create and kill new group composed of many units of the system. In this paper, We propose a strategy of self-organization. We call the strategy an Genetic Cell Production Algorithm (GCPA). The GCPA is based on the Genetic Algorithms, which are search algorithms based on the mechanics of natural se1ectiol.r and n atural genetics. We also propose a estimation method for the distributed system, which can be described by relations among subsystems. To simulate the self-organization based on the GCPA, we designed a distributed s ystem, which has a hierarchical cell-structure based on the concept of CEBOT. By using the model of a distributed system, some simulational results and analysis are reported in this paper, to verify the efficiency of the GCPA.

In this paper, a methodology is proposed to obtain a stable control law for the manipulators which perform contact tasks. The methodology is based on the Lyapunov direct method. The subject manipulators are nonlinear redundant multi-link manipulator systems which are interacting with a flexible wall with collision phenomena at the contact of tasks. The stability and response of a system are examined by parameter studies of numerical simulation. As the demands for rapid motion of robotics has been increasing in the field of industry to achieve higher efficiency, collision has become a problem to be solved, because every task includes contact when a manipulator acts on an object. In this paper we prove theoretically by Lyapunov direct method that this nonlinear system can be controlled stably with the combination of linear feedback and feedforward to compensate gravity without any expectation of the manipulator’s robustness. We also prove that the collision has the stabilization effect. It is addressed that collision can be used to control contact tasks of general elbow-type manipulators.

A six-degree-of-freedom micromanipulator using PZT actuators has been designed and tested. The micromanipulator is very small and light, because it is made of PZT actuators. Since this micromanipulator has a position and force feedback system, it can control desired poses and forces. Since the manipulator has 6 degrees of freedom, its tip can move along three axes, and can also rotate along each axis. A fuzzy-like variable gain feedback control system is employed, making this system perform better than the fixed gain feedback system. These technical merits will make it possible to operate this dextrous micromanipulator in much more complicated environments under a microscope.>