Traditional single-cell mechanical characterization techniques (e.g., atomic force microscopy) often face limitations in throughput, require invasive labeling, or fail to replicate physiological microenvironments, impeding their clinical utility for rapid cancer cell analysis. To address these limitations for automated characterization of cellular mechanical properties, this study proposes a novel method using microchannels with narrow geometric structures to measure cellular mechanical characteristics. A dynamic mechanical characterization technique with serially connected microchannels simulates malignant tumor cell deformation and migration in vivo, enabling precise identification of three malignant tumor cell lines and three normal cell lines through consecutive compressions. High-speed imaging combined with computer vision and image processing techniques facilitates rapid and accurate automated analysis for tumor cells. Furthermore, this study reveals that the mechanical properties of the cell nucleus determine the overall cellular mechanics, with the differences between tumor and normal cells attributed to variations in nucleus mechanics. This approach shows promise for early cancer diagnosis.

Micro-nano robots must break the symmetry of the flow field to generate net displacement in the low Reynolds number environment. The spherical micro-robots utilize the frictional forces generated through interaction with the surface. We designed a magnetic microroller robot powered by the rotating AC magnetic field. Here, we employed dual measurements of laser ranging and computer vision to demonstrate that a single 100 μm microroller maintains a lubrication film of 1 to 15 μm with the surface during normal motion. We found that the translational velocity of the microroller is correlated with the lubrication film thickness. Based on the robot's gravity, we controlled an additional downward gradient magnetic field to effectively increase the load of robot and reduce the lubrication film thickness, thereby controllably increasing the translational velocity of the robot. For example, the gradient magnetic field generated by superimposing a 30mA direct current input can reduce the lubrication film thickness from 8 μm to 4 μm in a 10 Hz rotating magnetic field, and increase the translational velocity from 230 μm/s to 460 μm/s. The enhancement of the robot's motion performance enables it to better control its movement in fluids. Finally, we validated the strategy for controllable acceleration of micro-scale particles rolling on surfaces, applied to control fluid motion in multiple arteries within blood vessels. These results offer deeper insights into the physical motion mechanism of surface robots and hold significant implications for future applications in biomedical engineering.

The development of magnetic soft microrobots has been constrained by the lack of precise control of microactuator’s programmability. To address such an issue, we use a piezo-driven two-fingered microhand to selectively position the magnetic microactuators within a soft scaffold. Each microactuator is sequentially oriented to a desired direction through surface rotation by applying magnetic field–based torques, and is then fixed to the scaffold using ultraviolet (UV) cross-linking. A detailed analysis is conducted on the spatial positioning capability of the microhand’s parallel mechanism and the magnetic programming performance of electromagnetic coils’ orientation control. To overcome the inefficiency and inaccuracy of labor-intensive manual assembly, we propose an automated assembly strategy to create magnetic soft-bodied microrobots following our design. The multiple fabricated microrobot prototypes exhibit programmed 2D and 3D shape transformations and various robotic gaits for surface locomotion. This strategy can enable the rapid fabrication of multimaterial 3D magnetic microrobot designs with potential applications in robotics, biomedical engineering, and environmental governance. Note to Practitioners—The motivation of this work is to address the limitations in current fabrication methods for magnetic soft microrobots, which include 3D printing, heating, mold casting, and chemical synthesis. These approaches fall short when creating microrobots with arbitrary structures, multimaterial compositions, and complex magnetization profiles. Micro-assembly offers a potential solution, yet existing techniques depend on either time-consuming manual assembly or costly equipment lacking sufficient flexibility for 3D spatial manipulations. In this work, a 3-degree-of-freedom, high-precision parallel microhand-based assembly method is proposed. The microhand provides high precision and speed for rapid positioning of assembly modules, while electromagnetic coils enable precise orientation in magnetization programming. Experimental results confirm the effectiveness of this method and demonstrate the robustness and adaptability of the automated fabrication strategy. This approach facilitates the fabrication of magnetic soft microrobots with specific deformation and locomotion capabilities according to design intent.

Micro-assembly is an emerging method to fabricate microrobots with multiple modules or particles. However, there is always a lack of a flexible and efficient method to freely create the desired magnetic soft microrobots. In this paper, an automated assembly system based on a two-fingered microhand is presented for fabricating magnetic soft microrobots. Our proposed system can automatically pick and place components to assemble microrobots with a two-fingered micromanipulator, and orient these components through an external magnetic field. The automated assembly has the advantages of high accuracy, high speed, and high success rate. It can endow magnetic microrobots with flexible material selection, arbitrary geometry design, and programable magnetization profile. We can make full use of this system to fabricate multiple magnetic soft microrobots. The experiment results demonstrate that this system can efficiently fabricate microrobots with excellent mechanical properties, which have application potential in robotics, biomedical engineering, and environmental governance.

In the last decade, researchers have been trying to develop many microrobots that mimic the extraordinary abilities of bionts in complex environments. How to fabricate the biomimetic microrobot with satisfying deformability and complex shapes to realize desired precise motion is the key issue. In this paper, we proposed an efficient programable fabrication method of the magnetic soft micro-robot through an on-chip photopolymerization system. The superparamagnetic nanoparticles were compiled according to the magnetic anisotropy and assembled in the micro-robot. Then these nanoparticles were immobilized by photopolymerization of the hydrogel polymer. With this fabrication method, a joint rotation mechanism was first fabricated to characterize the deformation performance under the magnetic field control. Besides, the snake-like micro-robot were also fabricated, and the desired motions were achieved. The experimental results show that the proposed programable on-chip fabrication of magnetic soft micro-robot has the potential to facilitate the development of magnetic microrobots and their applications in the biomedical field.

The magnetic microrobot has become a promising approach in many biomedical applications due to its small volume, flexible motion, and untethered micromachines. The micro-chain robot is one of the most popular magnetic microrobots. However, the uncontrollable magnetic moment direction and quantity of the magnetic beads consisted in the existing self-assembled micro-chain robot limit their locomotion and applications. This paper proposed an on-chip micro-chain robot fabrication method to assemble the magnetic beads with controllable magnetic moment direction and quantity. The bead quantity can be controlled by the structure limits of the microchannel, and the direction of the magnetic moment can be adj usted by the integrated external magnetic field. The assembled magnetic beads are then glued by the hydrogel under UV exposure. The micro-chain robots with different quantities and magnetic moment directions of the magnetic beads were successfully fabricated and tested in experiments. Due to the array structure of the microfluidic device, batch manufacturing of low-cost magnetic robots was achieved in our method. The movement of dual-bead microrobots with two orthogonal magnetic moment directions was analyzed and compared. One of the dual-bead microrobots was applied in the transportation of the hydrogel module using pushing and pulling modes. It indicated that the proposed controllable on-chip fabrication of the magnetic micro-chain robots has the potential to enhance the microrobot ability in biomedical applications.

Microfluidic devices for cell immobilization have significantly advanced the biological analysis at the single-cell level. However, the previous research on immobilization of multiple single cells, especially with deterministic quantities, is insufficient. In this paper, we proposed a novel microfluidic device based on the passive hydrodynamics and the uniform geometric design principle, which can array different numbers of cells in every capture cavity. The capture cavities could be stretched to accommodate more cells, and the trapping force was adjusted by modifying the related geometric parameters of the inside channel. The whole procedure was monitored and further automatized by integrating computer vision technology under a microscope. On the proposed integrated on-chip platform, we realized full-automated arraying of a single cell, two cells, and three cells on a single chip, achieving success rates up to 95%, 75%, and 72%, respectively. As a primary experimental demonstration, the cell viability test of arraying multiple cells with different quantities showed excellent biocompatibility and no significant association between trapping quantity and cell survivability. We envision that the proposed quantity-controllable, high-efficiency microfluidic devices for multiple cell arraying could be a powerful platform for an in-depth study of cell heterogeneity and cell communication between multiple cells.Note to Practitioners—This article is motivated by the biomedical applications of multi-cell arraying. The designed microfluidic devices employ passive hydrodynamics, and the capture cavities are stretched to accommodate different numbers of cells. The whole arraying procedures are automatized using computer vision technology. Simulations and experiments demonstrate the high efficiency, controllability of the cell quantity, and excellent biocompatibility.

In this paper, an automated tracking system with head and tail recognition for time-lapse observation of free-moving C. elegans is presented. In microscale field, active C. elegans can move out of the view easily without an automated tracking system because of the narrow field of view and rapid speed of C. elegans. In our previous works, we constructed an automated platform with 3D freedom to track centroid region of the nematode successfully. However, tracking time was not long enough to support a full time-lapse observation. Our proposed system in this study integrate the detection method in horizontal plane with depth evaluation more tightly. Tracking time and response speed have been greatly improved. Besides, we make full use of curvature calculation to make the system recognize the head and tail of C. elegans and the recognition rate can be up to 95%. The results demonstrate that the system can fully achieve automated long-term tracking of a free-living nematode and will be a nice tool for C. elegans behavioral analysis.

We have successfully achieved manipulation and assembly of microbeads having the size of 100μm diameter by hemispherical end-effectors with high stability and accuracy. The motivation of achieving assembly of actual cells lies in the great significance of it in tissue regeneration and cell analysis. Firstly, the most difficult problem we need to solve is the releasing problem caused by adhesion force. The viscosity on cell surface is much larger than the microbeads which makes cell releasing challenging. Secondly, the cell can generate its deformation, then contact area with end-effector will change during grasping process. This may influence the adhesion force and also bring problem to releasing. Thirdly, cell is much smaller, around 15μm in diameter, so we need to fabricate smaller end-effector to achieve successful manipulation and ensure the stability in the meantime. In this paper, we realize the manipulation by decreasing the adhesion forces and apply vibration to release a cell stably. We found the appropriate scale size for the end-effector is around 10μm diameter. It can not only grasp a 15μm cell but also bring little interference to the environment. As a demonstration of the proposed manipulation method, the repeated experiments were conducted to explore the dependence of adhesion force on the grasping distance, which can be helpful in the improvement of successful rate. Finally, we achieved automatic cell assembly using Hela cells.

For generating interactive behavior of robot to build a long-term relationship between humans and robots, we focus on the difference in familiarity of the human behaviors during conversation. It is difficult to extract interaction motion features correlated to such familiarity as a model in manual. Therefore, we use a machine learning technique: convolution neural network to learn and generate interaction behavior with different familiarity. In the evaluation experiment, we generated interaction behavior using a convolution neural network, which learned from the behaviors of friendship and unknown relationship, who have high and low familiarity respectively. We evaluated how much such interaction behavior affect the human impression by questionnaire survey.

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.

Recently, manipulation and observation of the cells are actively conducted in order to analyze the biological phenomena. Since the micro hand is usually fixed to the work environment, grasping target point of the cell on the opposite side of the micro hand by using a micro hand is limited by narrow workspace. If we move the micro hand in vertical direction to grasp the target point of the cell on the opposite side of the micro hand, we cannot focus the micro hand and the object in the microscopic field of view at the same time. In order to overcome the limitations of the limited workspace of micro hand, we assist the target point of the cell grasped by translation and rotation of the automatic stage. In this paper, we propose an automatic stage system for support the operation of the micro hand. Our automatic stage system can detect the object in the microscopic field of view by the template matching using Hu moment invariant and determine the grasping convex part of the object. by convex hull. Additionally this system can do 2d path planning considering convex part of the object to want to grasp and obstacles, and lead the micro hand to the object.

The paper describes a method of fault-tolerant adaptive gait generation based on CPG controller with interlimb coordination for multi-limbed working robot. Multi-limbed robot is expected to work in dangerous, complicated narrow spaces, where human workers cannot reach. However, if one of the limbs is broken in the dangerous/narrow working space, human operators cannot go to the space to repair it. Even in these situations, the proposed method generates a new gait adaptively using the remaining usable limbs depending on the current situation of the multi-limbed robot. This fault-tolerant ability is effective for multi-limbed robots working in dangerous/narrow space. The method is implemented to a model of a multi-limbed robot “ASTERISK” in a dynamical simulator (ODE). Experimental results show effectiveness of the proposed method.

The reliable manipulation of micro-objects has been a still difficult work in scientific and technical field due to scale effects. This paper presents two types of release methods, using local stream and inertia force generated by 3D high speed motion of an end effector, for releasing and accurate positioning of biological cells. Two-fingered microhand driven by DC motors for both end effectors and PZT actuators for right end effector is employed. A parallel mechanism controlled by three PZT actuators generates 3D high speed motions to release cells adhered to one of the end effector. The local stream and inertia force created by high speed motion of the right end effector detach the cells adhered to the left end effector and right end effector, respectively. To generate the necessary external forces for separation of the attached cells, the vibration having high frequency and suitable amplitude is applied. For accurate positioning of the object, circular motions are proposed. To verify the advantage of the proposed motion, we compare five motions, three 1D motions and two circular motions. Experiments were conducted employing 16μm NIH3T3 cells. From these analyses of experiments, we conclude that the proposed motions can detach micro objects (100%) with high position accuracy (3±0.7μm) on desired position after release.

Visual tracking of objects subjected to non-linear motion and appearance changes has shown to be a difficult task in computer vision. While research in visual object tracking has progressed significantly in terms of robust tracking of objects subjected to non-linear motion and appearance changes, these algorithms has shown limited capability for long term tracking of handheld objects during human-object interactions. The failure in tracking is a consequence of abrupt changes in the handheld object motion resulting in tracker drifting off the optimal object space. In this paper, we present a novel 3 layer RGB-D image model formulated with Bayesian filters that tracks handheld object using near constant velocity motion model. Our method divides the image into three layers of abstraction where each encodes visual information of environment, human, object and contributes toward precise localization of the handheld object during tracking. A boundary re-alignment step is introduced during tracking such that the tracker predicted object region is re-aligned to the optimal object region, therefore reducing the likelihood of tracker drifting off the object space. This compensation of the tracker prediction offset enables our algorithm to robustly track handheld object subjected to abrupt changes in motion during manipulation.

Single cell analysis has attracted much attention for revealing detailed and localized biological information. A local environmental control technique is desired when analyzing the detailed and localized properties of single cells. In this paper, we propose a local environmental stimulation system with micro dual-pipettes to stimulate the local reagent concentration dynamically, freely and automatically. When the local environment is controlled with chemical stimuli, the chemical solution is diffused and affects other objects. The local environment stimulation system with micro dual-pipettes can solve this problem by using spout pipette and suction pipette. As a cell analysis system, system quantification is necessary, so we try to realize it using a fluorescent substance. First step, we try to measure and control the light intensity. As an application of the system, the system can construct two-dimensional cell-organization by peeling off certain area of cell-sheet. Therefore, we try to control the area of peeling off cells using the system.

Recently micro manipulation techniques for cell or microorganism has attracted attention in life sciences. In this paper, non-contact manipulation method using water stream is proposed. Water stream is generated by a glass needle vibration that is actuated by a piezoelectric actuator. The stream is controlled by changing input voltage or frequency to the actuator. An accuracy of the motion of a piezoelectric actuator is in nano-meter order, so the stream is considered to be controlled precisely. The manipulator works in 3 dimensional space, that means water stream is generated in 3d space. We focused on the rotational stream generated by the glass needle 2-dimensional circular vibration. By using the resonance in a structure of the manipulator and the actuator's vibration, circular vibration can be generated by only one actuator. There is no need to use two actuators for generating circular vibration, so the structure of the manipulator is quite simple. In this paper rotational stream around the glass needle is also analyzed in 3d space using micro beads. This manipulator has the similar characteristics to the existing research of contact manipulation, so we think our method also have the capability to conduct contact manipulation.

This paper presents an active release method of microobject for the improvement of the position accuracy after releasing by using 3D high speed motions of an end effector. In the micro manipulation, the release task is the challenge work due to adhesion forces. To overcome the adhesion force and to place microobject accurately on the desired location, in this paper, we propose a high speed motion by analyzing dynamic model of manipulated end effector and attached microbeads. Two fingered microhand driven by DC motors and PZT actuators is utilized for this paper. Parallel mecahnism with three PZT actuators was used for making 3D motion at high speed. To generatge high acceleration of end effector, many researchers applied simple vibration by using an additional PZT actuator. In our research, 3D high speed motion with large amplitude was achieved by only using a compacted parallel mechanism. To verify the advantage of the proposed motion, we compare five motions, 1D motions (X, Y, and Z direction) and circular motions (clockwise and counterclockwise direction), by changing the frequency and moving distance of the end effector. From these results of experiments, we conclude that the circular motion can detach microobjects with high placing accuracy after release.

In the field of medicine and biology, many studies to be related to regenerative medicine are accomplished. In particular, the purpose of helping the operation of the cells under a microscope, many research related to micro manipulation techniques with robotic technology has been proposed. In such background, we studied two finger micro hand that realized control of the sub-micro order size object. The accurate operation of the end effector against the object by the micro hand is demanded to users. To reduce the burden, we focus on making the manipulation easy. User can perform micro manipulation with rough operation by using the actuator that varies in size. Since the actuator fills space between the end effectors and the object. Then we focus on the gel that varies in size. In this paper, we evaluate the gel that varies in size. Then we propose the manipulation that take advantage of the gel.

In this paper, a dynamic releasing method for high-speed biological cell manipulation is proposed. A compact parallel mechanism, used for grasping and releasing microob-jects, was utilized for generating controllable vibration to overcome the strong adhesion forces between the end effector and the manipulated object. To reach the required acceleration of the end effector, which is necessary for the detachment of the target object, vibration in the end effector is generated by applying sinusoidal voltage to the PZT actuator of the parallel mechanism. For the necessary acceleration, we focus on the frequency of the vibration, while keeping the amplitude of the PZT actuator vibration small (14 nm) to achieve precise positioning. Releasing of microbeads and biological cells is conducted and results are compared for the first time. The effect of the air and liquid environments are also investigated. Successful releasing (97.5%) of biological cells proves that the proposed active releasing method is an appropriate solution for the adhered biological cells during the releasing task.

Robots operating in human environments must have the ability to autonomously acquire object representations in order to perform object search and recognition tasks without human intervention. However, autonomous acquisition of object appearance model in an unstructured and cluttered human environment is a challenging task, since the object boundaries are unknown in prior. In this paper, we present a novel method to solve the problem of unknown object boundaries for handheld objects in an unstructured environment using robotic vision. The objective is to solve the problem of object segmentation without prior knowledge of the objects that human interacts with daily. In particular, we present a method that segments handheld objects by observing human-object interaction process, and performs incremental learning on the acquired models using SVM. The unknown object boundary is estimated using sequential back-tracking via exploitation of affine relationship of consecutive frames. The segmentation is achieved using identified optimal object boundaries, and the extracted models are used to perform future object search and recognition tasks.

Single cell analysis has attracted much attention to reveal the localized biological information in detail. Local environmental control technique is developed to analyze the localized detail properties of single cells. In this paper, we propose the local environmental chemical stimulation system with micro dual pipettes to stimuli the local reagent concentration dynamically and automatically. Local environmental chemical stimulation by dual pipettes is applied to the rotational speed control of bacterial flagellar motor, which is a rotary molecular machine. Here, we show quick response and rotational speed control of Na-driven flagellar motor in both accelerating and relaxing directions was demonstrated by automatic switching the local spout between Na-containing and Na-free solutions with dual pipettes. It was shown that the rotational speed could be maintained by automatic controlling the spouting velocity of Na-containing and Na-free solution with multiplying the applied DC voltage. Furthermore, it was confirmed that by applying the P-control, rotational speed of flagellar motor could be controlled more stably.

Brain Machine Interface systems provide ways of communication and control of a variety of devices that range from domestic appliances to humanoid robots. Most BMI systems are designed exclusively to control devices using low-level commands, or high-level commands when devices with pre-programmed functionalities are available. In this paper, we build on our previous work on BMI-based Learning System in which we presented a different approach for designing BMI systems that incorporate learning capabilities that relieve the user from tedious low-level control. In this work, we extend the capabilities of our framework to allow a user to be able to teach and evaluate a robotic system by using a BMI. We provide general system architecture and demonstrate its applicability in new domains such as teaching a humanoid robot object manipulation skills and evaluating its performance. Our approach consists of 1) tele-operating robot's actions while robot's camera collects object's visual properties, 2) learning manipulation skills (i.e. push-left, lift-up, etc.) by approximating a posterior probability of commonly performed actions when observing similar properties, and 3) evaluating robot's performance by considering brain-based error perception of the human while he/she passively observes the robot performing the learned skill. This technique consists of monitoring EEG signals to detect a brain potential called error related negativity (ERN) that spontaneously occurs when the user perceives an error made by the robot. By using human error perception, we demonstrate that it is possible to evaluate robot actions and provide feedback to improve its learning performance. We present results from five human subjects who successfully used our framework to teach a humanoid robot how to manipulate diverse objects, and evaluate robot skills by visual observation.

This paper presents a chip containing a flexible scaffold which facilitates the construction of tissues with different shapes. The chip, entirely made of Polydimethylsiloxane (PDMS), has 2 main components including actuator and channel layers. The actuator layer consists of a 6×6 array of membrane actuators, with round shapes. The channel layer has a single layered structure due to the simplicity in chip assembly and the ability to observe seeded cells via a microscope. The actuator array offers a flat surface, like a normal cell culture dish, in the rest state, while it temporarily offers a scaffold structure when actuators are activated. By changing the actuation pattern, formation of many scaffold structures is possible. To demonstrate the utility of this chip in biological application, a syringe pump is connected to all actuators to produced 2 different scaffolds, enabling the fabrication of multiple flat round and lattice shaped tissues. NIH3T3 cells with the amount of 5×106were seeded on the scaffold and kept inside the incubator for 24 hours. The 25 round shaped tissues with an average diameter of 623.87 μm were simultaneously fabricated when a scaffold with large deformed actuators was used. The lattice shaped tissue with a line width of about 300 μm was also fabricated with a different scaffold structure which has less actuator displacement. Results suggest the potential usage of this chip for the preparation of many building units with different structures, without the necessity of making a new mold for a new tissue shape.

Single cell analysis has attracted much attention for revealing detailed and localized biological information. A local environmental control technique is desired when analyzing the detailed and localized properties of single cells. In this paper, we propose a local environmental stimulation system with micro dual-pipettes to stimulate the local reagent concentration dynamically, freely and automatically. When the local environment is controlled with chemical stimuli, the chemical solution is diffused and affects other objects. The local environment stimulation system with micro dual-pipettes can solve this problem. By using spout pipette and suction pipette, it is possible to use local stimuli without affecting other objects. For evaluating the locality of the system, we use a fluorescent substance and measure the diffusion of the spouted solution.

This paper addresses the problem of mental fatigue caused by prolonged use of Brain Machine Interface (BMI) Systems. We propose a system that gradually becomes autonomous by learning user preferences and by considering error perception feedback. As a particular application, we show that our system allows patients to control electronic appliances in a hospital room, and learns the correlation of room sensor data, brain states, and user control commands. Moreover, error perception feedback based on a brain potential called error related negativity (ERN) - that spontaneously occurs when the user perceives an error made by the system - was used to correct system's mistakes and improve its learning performance. Experimental results with volunteers demonstrate that our system reduces the level of mental fatigue, and achieves over 90% overall learning performance when error perception feedback is considered. Note to Practitioners - This paper suggests a new approach for designing BMI systems that incorporate learning capabilities and error perception feedback in order to gradually become autonomous. This approach consists in learning the relationship between sensing data from the environment-brain and user actions when controlling robotic devices. After the system is trained, can predict control commands on behalf of the user under similar conditions. If the system makes a mistake, user's error perception feedback is considered to improve the learning performance the system. In this paper, we describe the methodologies to design and build hardware and software interfaces, acquire and process brain signals, and train the system using machine learning techniques. We then provide experimental evidence that demonstrates the effectiveness of this approach to design BMI systems that gradually become autonomous.

In this work, we present a high-speed pick-and-place method for cell-assembly applications. Besides range of motion and accuracy, rapidness of a manipulation system is an important parameter, which is so far underrated in related studies. To achieve high-speed micromanipulation, obtaining 3D positions of both the target microobject and the end effector rapidly is necessary. In addition, controlling the vibration of the end effector, which is greater at high speed, is another arduous task. We propose a new fast detection algorithm for both the target microobject and the end effector for achieving high-speed control of the system. Moreover, to realize the stable control for very fast movements, the vibration of the system is compensated. High-speed control of the microhand system is demonstrated with preliminary experiments consisting of pick-and-place actions of 40 to 60 μm microspheres; we aimed at performing a manipulation task in 1 second. Comparison with similar studies shows the merit of the proposed automated high-speed micromanipulation system.

Recently, with the development of life science field, micromanipulation technology has attracted attention. A two-fingered microhand system, that has been developed as a micro manipulator, can perform dexterous cell manipulation such as grasping, rotating, and transferring using two end effectors in a chopstick-like motion. The automated manipulation uses processing results based on all-in-focus (AIF) images and depth map obtained from the vision system; however, errors in the results still reduce the efficiency of the system. In this study, we introduce an automated grasping system that corrects the image processing error using the reaction force from the target object during grasping maneuvers. In our improved microhand system, micro force sensors that comprises strain gauge are attached to the two fingers of microhand. The two fingers with micro force sensor are set to be able to measure the horizontal and vertical forces to detect grasping state, precisely. Using the sensor information and the image processing results, we demonstrate that this system improves the accuracy and success rate of automated grasping.

In the fields of medicine and biology, it is essential to realize fine manipulation. Therefore, micromanipulation techniques and micromanipulators such as microgrippers and optical tweezers have been developed. We have developed a two-fingered microhand which is using the parallel mechanism to realize precise and stable micromanipulation. However, the previous microhand has problems about workspace and vibration. In this paper, the development of a new microhand which solves problems of previous microhand. The characteristic of new microhand is to enlarge the workspace utilizing the singularity of the parallel mechanisms. Inverse kinematics and structural analysis are used to analyze the workspace, and we show that results of two analyses match. Vibration analysis simulates transportation task and grasping task for manipulation. The new microhand has a potential to reduce the vibration by vibration analysis results.

Keyframe selection is the process of finding a representative frame in an image sequence. Although mostly known from video processing, keyframe selection faces new challenges in the lifelog domain. To obtain a keyframe that is close to a user-selected frame, we propose a keyframe selection method based on image quality measurements and excitement features. Image quality measurements such as contrast, color variance, sharpness, noise and saliency are used to filter high quality images. However, high quality images are not necessarily keyframes because humans also use emotions in the selection process. In this study, we employ a biosensor to measure the excitement of humans. In previous investigation, keyframe selection using only image quality measurements yielded an acceptance rate of 79.70%. Our proposed method achieves an acceptance rate of 84.45%.

We propose a social navigation model that allows a robot to navigate in a human environment according to human intentions, in particular during a situation where the human encounters a robot and he/she wants to avoid, unavoid (maintain his/her course), or approach the robot. Avoiding, unavoiding, and approaching trajectories of humans are classified based on the face orientation on a social force model and their predicted motion. The proposed model is developed based on human motion and behavior (especially face orientation and overlapping personal space) analysis in preliminary experiments. Our experimental evidence demonstrates that the robot is able to adapt its motion by preserving personal distance from passers-by, and approaching persons who want to interact with the robot. This work contributes to the future development of a human-robot socialization environment.

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.

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.

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.

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.

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.

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.

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, 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.

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.

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.

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.