Physical therapist (PT) emphasizes their haptic feedback during diagnosing patient symptoms. However, there is no standardized method to quantitatively assess PT's haptic sensation. In this paper, we report the difference of the haptic sensation between experts and novices using the end-feel training robot. The training robot is driven by the combination of the motor torque (controllable force) and the spring force (uncontrollable force). We employ three kinds of force protocol which imitates human end-feel reaction force. In the subjective experiment, the PTs are presented the reaction forces from the training robot and answered the most similar end-feel. We divide the PTs into two groups based on the similarity score using K-means++. The PTs are clearly classified into the high score group and the low score group. Depending on to the questionnaire, the PTs in the high score group worked long years and treated motor system disease patients mainly. This result indicates that our scoring method utilizing the training robot can evaluate the PT's haptic sensation quantitatively.

Moving to the location designated by the user is the most fundamental task for a mobile robot. Remote control is one of the effective solutions to navigate the robot to the target location, but the user suffers from the burden to continuously concentrate on the remote control. As the result, several users are required in accordance with the number of robots to operate. In this paper, we propose the remote control system that uses touch panel interface, simultaneous localization and mapping (SLAM), and motion planning to achieve autonomy of mobile robots. To navigate the robot in the proposed system, the user only designates the destination and via-points by touching on the map estimated by the SLAM. After receiving the user's input, the Rapidly-exploring Random Tree (RRT) generates the feasible path to the destination using the estimated map. The effectiveness of the proposed system is verified through experiments where multiple mobile robots are remotely controlled.

In this paper, we propose a producing method of softness sensation using device vibration. The basic idea of the softness producing method is to provide a softness illusion of stimulating cutaneous mechanoreceptor by vibration. A prototype device is developed to verify effect of parameters of the vibration: frequency, amplitude and wave shape, on softness sensation. We create a database which indicates relationship between softness sensation and the vibration parameters to control the prototype device. Then subjective experiment is conducted for validation of the softness producing method. Experimental result shows that the proposing method can be used for softness sensation producing with valid resolution.

The quantitative evaluation of product usability is important for product design. In this paper, we propose an evaluation system for product usability using a human mimetic robot hand with a tendon skeletal model. The proposed system enables us to evaluate product usability of a physical object, such as a prototype. To realize the system, we developed a robot hand which has a human mimetic structure. The design concepts of the robot hand are to imitate the human finger size, degree of freedom and fingertip structure. Ease of control is also characteristic of the robot hand. We propose to use tendon forces to evaluate the product usability. The joint torques during manipulation of the product are obtained from sensors on the robot hand. The tendon forces are calculated from the joint torques using the tendon skeletal model. Precise imitation of human finger structure makes the sensed joint torques similar to those of humans. The obtained joint torques are expected to be similar to those of humans. To evaluate the effectiveness of the proposed system, we conduct the experiments where the robot finger pushes cell phone button to evaluate its usability. The experimental result is verified by comparing with the existing questionnaire results from Ikeda [1]. The calculation score of the proposed system reflects the questionnaire result. These results indicate that the proposed system can quantitatively evaluate the actual product usability.

In this paper, we propose a novel haptic device that gives weight and friction illusions. Sensing a slip condition at a fingertip plays an important role to estimate the weight and friction properties of an object. This fact suggests that controlling the contact condition could yield weight and friction illusions. Based on this idea, a prototype device was developed that controls the contact surface between a fingertip and a rigid plate based on a camera-based eccentricity control. The desired eccentricity profile was given from the mathematical relationship between the eccentricity and the surface deformation, which is obtained by known material parameters, vertical/lateral forces applied on the contact area, and static friction coefficient. The performance of the developed device was evaluated through human experiments. The experimental results show the statistically significant difference between presented weight and friction conditions.

In this paper, we focus on the hand posture when a human subject pinches an object, and the correlation between the results of sensory evaluation by the subject and the tendon force of the subject's fingers are investigated. Surface electromyogram (surface EMG) and pinching force are measured during the pinching motion of human subjects. Experimental results show that subjects feel comfortable pinching a 60 [mm] cylinder. The surface EMGs are lower in the vicinity of 60 [mm]. Furthermore, a tendon-driven robot hand is developed as a sensing hand prototype. The surface EMGs and the motor torque are compared in a pinching experiment using the tendon-driven robot hand. Experimental results show that the tendon-driven robot hand is effective for quantitatively evaluating pinching effort. Simulation of the pinching motion is conducted using a simple finger model. The simulation results show the importance of finger posture and the moment arm in estimating tendon force. Taken together, these results demonstrate the possibility of conducting quantitative evaluation using the tendon-driven robot hand.

In this paper, we propose a tendon skeletal finger model and discuss which finger postures the human feels easy to pinch based on the tendon forces and the human experimental results. The finger model mimics a human tendon skeletal structure. The tendon forces during the pinching motion were simulated using the finger model. Simulation results show that the tendon forces closely mirror the human muscle activity. Sensory evaluation of subjective pinching effort was conducted with five subjects. The subject pinched five kinds of cylinders, from 20 [mm] to 100 [mm]. The pinching force and the surface EMGs were simultaneously measured in the experiment. Based on the human questionnaire tests, we investigated which finger postures the human feels easy to pinch a cylinder. The results show that the pattern of the EMGs measured by the experiment is very similar to that of the tendon forces calculated by the finger model simulation. This indicates that the tendon force is a useful index of the subjective pinching effort and it can be used for the quantitative evaluation instead of EMGs.

Humanoid robots and robotic manipulators with good dexterity are promising to enhance the factory productivity in next generation. Dexterity of robotic manipulators can be achieved by equipping an anthropomorphic robot hand with multiple fingers. Additionally, in order to manipulate various tools that humans are using in daily life, the size and the exerting force of the robot hand should be similar to that humans are. In this paper, we proposed a human-sized multi-fingered robot hand with detachable mechanism at the wrist. The robot hand can be split at the wrist into the hand part and the actuator part. The fingers are driven by wires and are controlled by actuators embedded in the arm part. The driving force from the arm part is transmitted to the hand part by gear mechanism at the wrist. The developed robot hand has the size of 200[mm](length) × 78[mm](width) × 24.6[mm](thickness) and can exert 10[N] at the fingertip. The performance of the developed robot hand was shown by a motion control experiment.

This paper presents the haptic interface system that consists of a base object and a haptic device. The desired force response is achieved by the combination of the real force response of the base object and the virtual force exerted by the haptic device. The proposed haptic augmented reality (AR) system can easily generate the force response of a visco-elastic object with a cheap haptic device and a base object that has the similar visco-elastic property to the target object. In the demonstration, the force response of the target object was generated by using a haptic device only (VR) and using both a haptic device and a base object (AR), respectively. The evaluation experiments by participants show that the AR method has better performance than the VR method. This result indicates the potential of the proposed haptic AR interface.

In this paper, a novel pointing device is proposed that utilizes the deformation of the fingertip. When a fingertip is pressed and slightly slid on a rigid plate, a partial slip, called an "incipient slip", occurs on the contact surface. While the deformation around the center of the contact area is small during the incipient slip, the boundary region moves to the sliding direction of the fingertip. The deformation changes depending on the sliding distance of the fingertip and the exerted force on the contact surface. The velocity of the pointer can be determined by the estimated distance and force based on the measurement of the deformation. In this study, the correlation between the sliding distance of the fingertip and the deformation and between the exerted force and the deformation are investigated. The degree of the deformation due to the sliding motion can be estimated based on the detected fingerprint center. The group delay spectrum tracking method is proposed for the detection of the fingerprint center. A prototype pointing device is developed to evaluate the operationality of the proposed device. Comparative experiments with conventional pointing devices are conducted. The validity of the proposed device is confirmed by the experiments.

In this paper, a grip-force control of an elastic object is proposed based on a visual slip-margin feedback. When an elastic object is pressed and slid slightly on a rigid plate, a partial slip, called "incipient slip," occurs on the contact surface. The slip margin between an elastic object and a rigid plate is estimated based on the analytic solution of a Hertzian contact model. A one-degree-of-freedom gripper consisting of a camera and a force sensor is developed. The slip margin can be estimated from the tangential force measured by a force sensor, the deformation of the elastic object and the radius on the contact area both measured by a camera. In the proposed method, the friction coefficient is not explicitly needed. The "eccentricity" is used to estimate the displacement of the elastic object at the contact area with high accuracy. The grip force is controlled by a direct feedback of the estimated slip margin. The proof of the contact stability by the proposed control is analytically given. As a result, the slip margin is maintained at a desired value, without occurring the gross slip against a disturbance traction force to the object. The validity of the proposed method is confirmed by experiments.

In this paper, a grip-force control of an elastic object is proposed based on a visual slip margin feedback. When an elastic object is pressed and slid slightly on a rigid plate, a partial slip, called "incipient slip" occurs on the contact surface. The slip margin between an elastic object and a rigid plate is estimated based on the analytic solution of Hertzian contact model. A 1 DOF gripper consists of a camera and a force sensor is developed. The slip margin can be estimated from the tangential force measured by a force sensor, the deformation of the elastic object and the radius on the contact area both measured by a camera. In the proposed method, the friction coefficient is not explicitly needed. The grip force is controlled by a direct feedback of the estimated slip margin, whose stability is analytically guaranteed. As a result, the slip margin is maintained to a desired value without occurring the gross slip against a disturbance load force to the object.

This paper proposes the new thin wire production system and wire conveyance device in it. The thin wire production system consists of the conveyance module, thin film deposition module, processing module and so on. The conveyance module is a key component among them since it decides the specifications of wire and performance of production system. Proposed conveyance module consists of transportation unit and rotation unit. This paper proposes the new mechanism to generate the transportation by difference of rotation action of transportation unit and rotation unit. Also, this paper demonstrates of the new mechanism by experiments. The experimental results show the performance of the wire transportation, and the prototype achieved the requirement for the practical use such as transportation speed of 300 mm/s.

In this paper, a novel pointing device is proposed which utilizes the deformation of the fingerprint. When the fingertip is pressed and slid slightly on a rigid plate, a partial slip, called "incipient slip", occurs on the contact surface. Since the deformation around the center of the contact surface is small, the center of the fingerprint can be detected during the incipient slip. The group delay spectrum (GDS) tracking is utilized to detect the center of the fingerprint. The velocity of the pointer is controlled by the changes of the contact area on the basis of the tracked center. A prototype pointing device is developed to examine the operationality of the proposed method. The experimental results show that an operator can control the pointer with high accuracy.