This study developed a motion discrimination method considering variation of EMG signals associated with lapse of time. In previous study, we proposed real-time discrimination method based on EMG signals of forearm. Our method uses hypersphere model as a discriminator. In motion discrimination using EMG signals, there is a problem to maintain high discrimination accuracy over time. It's known that EMG signals changes along with lapse of time. This study analyzed the effect of changes in EMG signals to our method. From result of the analysis, we propose adding relearning system of decision criteria to the discrimination system. A motion discrimination method that contains the relearning system was created and the effectiveness of adding relearning system was experimentally verified. The motion discrimination system was able to discriminate 3 hand motions with discrimination accuracy above 90 % and discrimination processing time below 300 ms even after the time has elapsed.

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Hemiplesia is one of late effects after stroke and causes different impairments. For example, the ability to generate and modulate force is impaired. This study focused on the technique that encourages force generation in an arbitrary direction. We introduced the technique of physiotherapy into rehabilitation robot and visualized force direction. The technique was verified with a patient with hemiplesia. The results suggested functional improvement and correlation between the recovery of force modulation and motor control. We considered the contribution of visualizing force to motor function.

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We discuss the development method of a skeleton type myoelectric prosthetic hand by using a laser cutting machine. This myoelectric prosthetic hand has five concepts for practical application; (1) Five fingers, (2) Gripping operation using the five fingers, (3) Structure of the hand to the collision,(4) Structure in the operation of the rehabilitation training and (5) low price, saving weight. Results demonstrated these concepts capabilities of the skeleton type myoelectric prosthetic hand.

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This paper proposes a training system for controlling the five-finger EMG-prosthetic hand that enables not only fast finger motions but also a strong grasping force. The proposed system is developed based on the control method equivalent to the five-finger prosthetic hand, and conducts three types of training: muscle contraction, muscle cooperation, and grip force training. In the contraction training and the cooperation training, the control ability of muscle force and the reproducibility of EMG patterns can be trained, respectively. Appropriate gripping force according to the hardness of an object can also be trained via the grip force training using a virtual prosthetic hand. The validity of the proposed system is demonstrated in the five-day experiments conducted for three subjects.

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This paper considered a rehabilitation device for leg paralyzed patients and developed a foot pedaled exercise device. This device has foot pedal driven by motor and crank mechanism, and forcibly moves legs fixed on pedals. To confirm performance of this device as a part of brain- machine interface (BMI) lower limb rehabilitation system, we investigated user's brain activity during his foot pedal exercise by electroencephalography (EEG) and near-infrared spectroscopy (NIRS). As a result, we confirmed that the brain activity characteristics measured at using our developed device is almost the same as the characteristics measured at using bicycle ergometer. This indicates that our developed device is possible to use a lower limb rehabilitation device.

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There is a tendency that the elderly persons decline in feeding and swallowing. It is known that the oral training such as a facial exercise has an effect to facilitate a smoothness swallowing motion. This paper describes a perspective on measurement and evaluation of face exercises using PET plastic bottle, based on the Electromyography (EMG). Here, the orbicularis oris muscle were focused for an evaluation. As a result of APDF analysis, it could be confirmed that the motion of puffing the cheeks had an effect to enhance the activity of the orbicularis oris muscle.

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This paper describes "an Independence Support System", which can assist standing up and walking motion from lying on a bed. In order to relive the burden of nursing care and help a handicapped person to be more independent This machine had problems to be solved. For example, frame is very heavy, power of walking assist device is weak and there is little safety. So, we improve this machine and solve these problems. Besides, we produce a guidance device to lead Support System to toilet. Therefore, Excretion care become easier. In this paper, we report the mechanism of Support System, improvement of this machine and guidance system.

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Following a rise in the elderly population, falling accidents caused by muscle weakness of the lower limbs will increase. This paper focuses on muscle force in each muscle of the lower limbs as an indicator for the fall risk assessment, and proposes a new estimation method of muscle force. The proposed method enables to estimate muscle force during training by determining the activity level of each muscle from the posture and force information at the center of pressure. The effectiveness of this method is shown through comparison between this method, IEMG, and a conventional method.

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In rehabilitation field, there is a need for quantitative evaluation that does not depend on the subjective evaluation of therapist. The final aim of this research is to develop a quantitative evaluation support system of shoulder joint motor function by use of the three-dimensional force display robot (URRobo). In this paper, we constructed a quantitative evaluation support system by implementing the proposed quantitative evaluation method of the shoulder joint motor function to the URRobo. The URRobo reproduced the inspection movement of the shoulder joint motor function performed by the therapist. During the inspection, the URRobo measured a subject's force and rotational angle about the six basic movements. Then, we carried out experiments to verify the inspection accuracy with the quantitative evaluation support system. As a result, it was confirmed that the sensitivity was 75% and the idiosyncrasy was 75%.

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An android model of human joint is an anatomical model consisting of minimum parts for reproduction of human motion. The purpose of this study is to analyze three-dimensional movement of the knee android model by comparing human knee movement. For this purpose, we measured the movement of the knee android model using VICON. We investigated the internal-external rotation and the anterior-posterior translation during the knee android model extension. As a result, we found that the internal-external rotation of the knee android model was similar as that of human knee and that the anterior-posterior translation cannot be reproduced. We investigated the possible cause.

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The basic structure of a Redundant Drive Manipulator (RDM) has been proposed to produce compliant motions with a higher bandwidth. The structure of the RDM can reduce the total endpoint inertia. Therefore, the RDM can be proper to produce such compliant motions. In this paper, the mechanical properties of the RDM is analyzed by comparing the numerical examples and simulation. First, we discuss how the proposed RDM can reduce a set of joint and link inertias along the motion direction, comparing the inertias of a simple 1-DOF manipulator with the proposed RDM. Then, how the design parameters which we determined affect to reduce the endpoint inertia of the manipulator in its motion direction.

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In this paper we present the first clinical application of a newly developed control method for wearable lower limbs exoskeleton robots. The method we developed is one based on using body joint synergetic effect, with a walking aid cane, to estimate and provide assist on the affected limb(s). The outcome of hemiplegic persons walking with the system shows the subjects immediately being able to walk with the system, and improvements in some gait aspects. This investigation exhibits the clinical applicability of the proposed method, and prospective gait function improvements of using the system. The finding contributes to the technology for cognitively assisted locomotion, which helps the locomotion of physically challenged people.

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Most of the patients who experienced a limb amputation or deafferentation suffer from phantom limb pain. Phantom limb pain is a refractory pain, and there are few effective treatments since the pathogenesis is unknown. Rehabilitation using virtual reality (VR) is promising as a new treatment for phantom limb pain. However, long-term therapeutic effect of VR rehabilitation is not examined because systems for VR rehabilitation are large-scale (this leads to high burden on patients and health care workers, for example) in most cases and it is difcult to do experiments frequently. The purpose of this study is the development of VR rehabilitation systems with high therapeutic effect and usability. By selecting devices with high accuracy and adopting non-contact measurement of 'ngers' movement, we have succeeded in developing two systems which realized reduction of burden on patients and health care workers, cost saving and high therapeutic effect.

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As survival rate of cerebrovascular disease due to improvements in medical care, the number of patients requiring such rehabilitation is growing. Since the effects of rehabilitation show only if it is continuous, it is hard to keep motivation in monotonous rehabilitation environments. Therefore, with the use of latest virtual reality devices, it is possible to a rehabilitation environments like taking a walk outside while being at the rehabilitation's facilities. This research is about a gait rehabilitation system with the use of a Head-Mounted-Display (from now on, HMD). This HMD uses a smart phone and a method for changing the field of view on the HMD when gait is detected by the smartphone sensors. As a result, it was possible to walk with a virtual environment displayed in the HMD. However, this HMD had low frame rate issues. Future work will improve frame rate and compare with high-performance HMDs such as the OculusRift.

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In our research, we aim to reconstruct the closed loop of the brain and body for stroke rehabilitation. Stroke patients need to be supported externally when trying to move paralyzed parts of their bodies. In order to know the onset time of voluntarily motions of the patients, the motion intention needs to be detected. If people try to move voluntarily, Movement related EEG is generated. However, the signal includes a lot of noises. In this paper, we propose a method to detect motion intention by EEG. Then, we study on utility of the proposed method by analysis result of a large number of data.

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In recent years, stroke hemiplegia patients are increasing. On the other side, therapist is decreasing. Due to these reason the patient is doing the voluntary training. Therefore, we aim to realize a robot to perform the training instead of the therapists. It is confirmed that therapists change the center of gravity of the patient, and adjusts the load on the paralysis side leg during standing training. The robot we developed has two arms with three degrees of freedom. These arms hold the waist of the patient, and adjust the center of gravity during standing training. This paper describes the overview of rehabilitation training robot and the effect of the robot on examinee.

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In this study, we developed a device for the purpose of assist of the rehabilitation. The method of the rehabilitation includes what's called mirror therapy. Mirror movement can expect an effect as rehabilitation of the symptom of hemiplegia. Therefore we developed the device which caused an illusion that a paralysis limb moved the arms because a reflected image let you exercise in this study. Because without using power, the structure of the device is simple and it is easy portable device. It is the structure that is relatively small because we use synchronous belt, linear guide and a pulley for mirror movement.

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Hemiplegic patients caused a foot drop and cannot be grounded in the heel. Therefore the heel rocker does not work. Currently, although the AFO is used for them, its dorsiflexion assistance is not enough for the patients, and it has not been adapted to the heel rocker support. In order to solve the problems, we had developed the artificial muscle-driven high-dorsiflexion support RT first prototype. However, the responsiveness of the artificial muscle is too slow to support the heel rocker. In addition, it cannot be adapted to the cadence. Therefore, we developed the high-dorsiflexion support RT second prototype which is adaptable to cadence and incorporated the spring system compensates to solve the problem of slow responsiveness.

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Recently, it is reported that the number of fall down accidents in elderly people has been increasing along with the progress of aging society. The main factor of fall down accident is the gap of the center of balance from declining in physical performance. Elderly people need to recover the declined in physical performance to prevent the fall down. One way to prevent the motion, it is walking training because it can do with low-stress. Then, we focused on the shoes which is used frequently and we develop the walking training system using the high-performance shoes. In this study, we developed the high-performance shoes which has two systems. One is the visual showing system that can see the walking state in real time, the other is walking assist system using pneumatics to lighten the burden that imposed on the body.

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Hemiplegia patients have difficulty in weight shifting to the affected side because of fear of falling down. The purpose of this study was to invent an implicit method that leads weight shifting to the affected side without being noticed by the patient to decline the fear of falling by using vibratory biofeedback providing center of foot pressure displacement. Just noticeable difference of sense of weight was used to increase the amount of weight shifting without being noticed. An experiment was carried out with 12 healthy people to derive just noticeable difference of sense of weight. A clinical study was carried out with 5 hemiplegia patients and the result was that the stance phase of the affected leg while walking increased after training only in the moderate paralytics. The result suggested the implicit method could make hemiplegia patients endure on the affected leg while walking.

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When a therapist measures range of motion in finger joints to evaluate patient's motor function of a hand, a therapist usually uses a goniometer that is an angle measuring instrument. When measuring finger joint angles, therapists put a goniometer to the patient's hand. However, the measurement with goniometer takes much time because there are many joints in a hand. To solve this problem, we developed a new system for measuring range of motion of finger joints and verified the measurement accuracy of the proposed system. The system gets depth data of fingers by using a depth sensor and displays the virtual fingers and the virtual goniometer in the virtual space. Then a therapist measures the joint angles of the virtual fingers with the virtual goniometer. It was confirmed that the patient's burden was reduced.

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This study intends to develop a rehabilitation bicycle for hemiplegic patients. In this paper, we describe design of an assistive mechanism for riding and control of a pedaling force. Hemiplegic patients are difficult to pedaling the left and right equally. Under the control of a pedaling force, we eliminate the discomfort of the patient's foot. We suggest such as impedance control as the control method for hemiplegic patients. Assistive mechanism which has springs and a plunger aids patients riding a bicycle.

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This paper proposes a novel approach for supporting postural change of children with severe motor disabilities between lying and sitting by using a wearable soft robotic device. 3D motion analysis revealed that pitch and yaw motions of the lumbar joint correlate with the change of center of gravity during the postural transition. A novel pneumatic accordion actuator is proposed, and 4 such actuators were designed for assisting movement of the lumbar joint. Experiments with a dummy baby doll proved t hat the proposed system is capable to change the posture of the wearer from supine to long sitting position and vice versa.

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There has been an increase in the demand for rehabilitation from the circumstance of an aging society. In the future, in order to achieve sufficient rehabilitation, the spread of rehabilitation robot is required. Thus, a variety of upper limb rehabilitation system is being researched and developed. But it is difficult for them to spread because they are heavy and expensive. So we propose a compact support system for upper limb rehabilitation that can carry out rehabilitation easily at low cost. An Armless Movable Robot is used in this support system. In this paper, we measure the muscular activity of the upper limb when using Armless Movable Robot in order to develop the application suitable for an individual patient.

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At present, rehabilitation for the hemiplegia patients has been widely carried out in Japan. Since these patients need hours of repetition training for their recovery, the burden for the therapists to carry out the rehabilitation training is heavy. Due to this reason, the hemiplegia patients mostly carry out the rehabilitation routine by their own. However, this may not make the recovery for the paralyzed leg possible. Therefore, in order to reduce the burden of the therapist and make the recovery of the patience's paralyzed leg possible, we have been developing standing assist rehabilitation robot in recent years. In this thesis, the weight balance of the examinee is evaluated and the ability of the robot to adjust the examinee's weight balance is confirmed.

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Aphasia is one of the condition of a higher brain function disorder. Aphasia is an obstacle which forgets the name of a thing. This research,develops a novel system using the tablet PC for supporting the rehabilitation of aphasia. The system supports diagnosis by conducting statistical analysis of the diagnostic result.

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In performing rehabilitation, it is effective to generate an illusion. In this study, we invented ball-rotation system inducing of illusion of motion by visual and tactile feedback and to the evaluation experiment of it. We conducted the evaluation experiment of equipment and an illusional indecement experiment on using it before. We plan to verify the appropriate angular velocity to induce illusion using device. Furthermore, we plan to verify the illusion in various way of grips.

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Natural human movement requires appropriate coordinated contraction patterns involving multiple muscles; without this coordination, such movement cannot be achieved. This paper proposes a novel rehabilitation method based on a combination of functional electrical stimulation and pattern classification to support the evaluation and control of muscle contraction patterns for patients with hemiplegia caused by stroke or spinal cord injury. In the experiment reported here, the relationships between stimulation current and forearm joint angles were investigated using exponential functions. The results showed that muscle contraction information can be transmitted between two subjects via electoromyograms and electrical stimuli.

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Although a patient with slight hemiplegia after stroke can stand up by using both his/her legs, he/she stands up by using mainly his/her healthy leg rather than his/her paralyzed leg. Therefore, a therapist guides a patient motion to be able to stand up by using both his/her legs well in balance or by putting more weight on the paralyzed leg. The final goal of our research is to develop a rehabilitation support robot of standing up training for patients with hemiplegia after stroke to restore normal standing up motion. For this purpose, we constructed the measurement system of standing up motion by using VICON. And actually, we analyzed the standing up motion to show the effectiveness of the system.

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An operator cannot obtain feeling of grasping in robot hand tele-operation with motion-capture data of operator's hand, because an operator does not grasp an object actually. If an operator cannot obtain feeling of grasping, an operator may move his fingers by mistake. Therefore, we build robot hand tele-operation system with pseudo grasping sense feedback by using the haptic device and the visual feedback system. By using this system, an operator can feel as though he grasped an object with own hand, when a robot hand grasps an object in the tele-operation with motion-capture data of his hand. Finally, we test the usability of this system.

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We propose haptic feedback methods based on proximity sensor output in teleoperation. Composed of four distance measurement sensors, the proximity sensors are mounted on the palm of the robot hand. When the palm of the robot hand faces an object, a plane of the object can be estimated. The operator Ls given a reaction force based on a model of virtual spring. The amplitude is determined by the distance to the estimated plane, and the direction is determined by the normal vector of the plane. In this paper, especially we propose three methods how the amplitude is determined by the distance, and we verify the differences of the operator perceiving the reaction force by each method.

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In robotic manipulation visual servoing is important to achieve dexterous and accurate handling. And one of the most important problems is occlusion by the robot's body. It is difficult to know the position and orientation of the object being manipulated when the robot manipulator handles it because it is hidden by the robot itself. If its position and orientation are estimated considering the occlusion by the robot, the robot can manipulate it by visual servoing more dextrously. In this paper, we propose an algorithm to estimate the position and orientation of the manipulated object during manipulation by using a 3D sensor. The 3D information of the total environment is observed by the 3D sensor, and the observed 3D point cloud information is classified into the manipulator, the object, and the others based on their 3D model. The proposed algorithm is verified in an actual robot manipulation system.

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It is important to display the force sense on the tele-operation of the robot. The authors have developed a master slave system which consists of a multi-fingered haptic interface and a humanoid hand robot. Both the haptic interface and the robot hand have 6-DOF robot arm and 15-DOF robot hand. This paper proposes the tele-presentation for the stiffness of the object. Experiments show high performance in stiffness of objects.

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In this article, we propose a novel robot hand called uGRIPP (Underactuated Gripper for Power and Precision Grasp) which has underactuated fingers. We designed an underactuated linkage which enables the robot hand to achieve an adaptive grasp, a pinch grasp and a manipulation by a palm of the hand. A prototype of the robot hand was developed. We conducted handling experiments to evaluate the validity of the robot hand.

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In Japan, the labor power is decreasing by the aging population and lower birthrate. In production fields, there is a big demand for robots to compensate for reduced manpower. To introduce them lead to such advantages as more efficient production, high quality and improvement of working conditions. Various robots have already worked in the factories. However, the functions performed by them are limited and difficult to adapt to different environments because most factory robots are only controlled by sequence control. To solve this problem, We used the pneumatic robot arm driven by pneumatic actuators. The pneumatic robot arm has 2 DOF and grasps an object from various directions because it is like a human hand. These advantages could relieve constraint condition for the posture of robot hand tip part. Therefore, We proposed grasp posture determination method that material handling system was divide into industrial robot and pneumatic robot arm. We used potential method to decide all joints angles of my system by desire position. We determined each joint angle of industrial robot and pneumatic robot arm in stages. Finally, by performing the specified task, We could verify my determined grasp posture and the validity of proposed grasp posture determination method.

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Generally, teleoperation of a robot hand with a monocular camera has problems of lack of depth information and the occlusion occur. The operator misrecognizes the position and posture of the object, and the robot hand cannot grasp the object. In the paper, to solve this problem, we use a proximity sensor, which we have developed, attached to the palm of the robot hand. The operator is able to recognize the position and posture of the object by using the proximity sensor. In addition, autonomy control based on the sensor enables to adjust the position and posture of the robot hand. We integrate operator control with autonomy control. The number of success of grasping the object increases and an operation burden decreases.

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In this paper, we propose a modular robot hand composed of RC servo motors which follows unknown shapes of objects using fingertip proximity sensors. The fingertip proximity sensor has been proved to enable the finger to keep constant distance and run parallel to an object by sensor feedback. The feedback control is simple and robust, and so it can be operated even using microcomputers and RC servo motors. High expandability is one of advantages of RC servo motors. By making the most of its characteristics, the robot hand can be changed degree-of- freedom (DOF) easily. The robot hand will be a variously deformable robot hand according to various purposes.

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We have developed a non-contact sensor called "net-structure proximity sensor" and a contact sensor called "slip sensor. " Both sensors are mounted on fingertips of our robot hand for object manipulation. The net-structure proximity sensor detects position and posture of an object, not only in non-contact but also in contact. The slip sensor detects pressure and slippage between an object in contact. In this paper, we investigate the outputs of these sensors under contact-state-transition between fingertips and an object, such as rapidly touch and forced posture change.

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This paper presents the development of a selfadaptive and versatile gripper. This hand has three fingers and each of the fingers has a drive roller to realize handling function. The selfadaptability of the hand is obtained using underactuation. The underactuated mechanism is composed of three planetary gear reducer. Also, die way of using planetary gear reducer is not the same as the one used by other researchers. Firstly, the principle and mechanism of the gripper are proposed. Secondly, design parameters are determined using static force analysis about a finger contacting with an object. Finally, effectiveness of underactuated mechanism and design parameters are confirmed by performing simulations considering dynamic behaviour.

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It is important for robots to obtain appropriate grasp positions autonomously to make stable grasps. This paper proposes an automatic generation algorithm for getting the optimum planar grasp. Each finger is replaced with a two-dimensional linear spring model. Grasp stability is evaluated by using the eigenvalues of the grasp stiffness matrix derived from the potential energy of the grasp. To decrease the number of searching iterations, we derive the partial differentiation of the matrix by the contact position parameters. Effectiveness of our method is demonstrated through numerical examples.

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In this paper, we develop a gear driven five-fingered robotic hand that fabricated by using 3D printer and can be easily assembled. This robotic hand uses series of gears to realize synergetic motions of the fingers. This hand can realize multiple grasps using a small amount of RC servo motors. We combine several parts into one to reduce the number of parts and eliminate screws from the hand to assemble robotic hand without using tools. We execute some experiments to confirm that the robotic hand can realize multiple grasps.

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It is difficult for a grasping mechanism used for industrial robots to correspond to various shaped objects. This is because the grasping mechanism of industrial robots are designed to each object. A human finger can grasp and operate objects well because a human finger is soft and flexible. So, this article focuses on the three-fingered hand with soft fingertips with translational joints. The touch area of soft fingertips is wider than that of hard fingertips, so soft fingertips are able to grasp various objects. We verified whether this hand could grasp various objects.

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This paper describes a high-speed manipulation by using an underactuated robot finger, where flick motion generated by a single actuator is proposed. First, we introduce an active-passive hybrid finger whose joint axes are arranged in nonparallel with each other. The finger mechanism features that the fingertip vibration trajectory is variable on a curved surface in 3D space based on the input of the active joint and the viscoelasticity of the passive joint. Then, the flick motion where the soft fingertip quickly traces an environment or an object, is explored. We reveal that the flick velocity vector can be controlled by the combination of the input frequency and amplitude of the active joint. Finally, we show experimental results by using a prototype robot for confirming the validity of the proposed method.

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This paper describes an underactuated robot hand having abduction movement mechanism in a palm. It is expected to improve the stability when a robot hand grasped an object by adding an abduction mechanism to a palm. In this paper, abduction mechanisms around thumb and around a small finger is proposed. Design of these mechanisms are explained particularly. It was confirmed that an effectivity of this mechanism to realize an stable grasping of an object experimentally.

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This paper presents feature extraction by deep leaning for in-hand manipulation. In the aging society, Robots which have versatile hands to manipulate different sizes and shapes of objects are required. In order to achieve robust in-hand manipulation, the current touch state has to be taken into account. But modeling of the contact states like multiple contacts and complex shapes of the object or the fingertip is difficult. So, machine learning was used for in-hand manipulation. However, information from touch states including redundant information is hard for machine learning to adapt to manipulation with different sizes and shapes of objects. We used feature extraction by deep learning to extract important information for in-hand manipulation.

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In this study, we analyzed the resistible force for soft material fingertip via contact surface image analysis. The resistible force is defined as the maximum tangential force at which the fingertip can maintain contact when applying and increasing tangential/shearing force. In our previous study [3][4], harder fingertips produce larger resistible forces when semispherical and cylindrical fingertips with flat surfaces were used. When a tangential force was applied, large deformation by bending and shearing occurred in the soft fingertip. It is assumed that this deformation affected the deformation of the contact area and the stress distribution over the contact area. In this study, the stress distribution over the contact area was analyzed via contact surface image analysis in order to confirm this effect.

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This paper proposes a new object manipulation method by means of a multi-fingered hand using a particle filter to estimate a position and attitude of an object. In our previous work [1], the object virtual frame has been presented instead of an actual frame to manipulate an object without any external sensing information. A desired position and attitude of the object, however, has not been necessarily realized using the method because of no external sensing information. In order to cope with that, a new virtual frame is proposed based on a 3D laser range sensor data including considerable noise and time-delay in this paper. Firstly a particle filter is designed to estimate the position and attitude of the object from the sensing information. Then the new virtual frame is designed based on estimations of the particle filter.

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This paper describes an underactuated robot hand whose link posture is controlled by using dynamic effect. First we show an analytical model of two link system which has an active joint driven by an actuator and a passive joint with a viscoelastic element (viscoelastic joint). Based on the model, we reveal the variable vibration center effect of the viscoelastic joint with respect to the input frequency and amplitude of the active joint. We then discuss how to control the finger link posture of robot hand by using the effect. Here we show the design orientation for keeping a contact with an object and for expanding the movable range. Finally, we experimentally confirm the variable vibration center effect and show a grasping motion by a prototype robot finger.

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A small pinching device with three opposed fingers using 3D cam mechanism for precise pinching is developed. The 3D cam mechanism is a backlash-less joint mechanism for robot hands that has been developed by authors. By combining two sets of 3D cam mechanism, two fingered pinching device also developed by authors so far. However, the pinching performance of two fingered structure is not stable enough for various objects. In this paper, we developed three fingered pinching device to increase the stability of pinching. The design and concept are presented and the pinching performance of a manufactured prototype is also discussed with experiments.

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We developed a block type programming tool "P-CUBE" for programming beginners including visually impaired. Users can create the program of mobile robot only placing programming blocks on the program mat. We expect that users can learn fundamental programming concepts (sequential, branch, and loop) by using P-CUBE. We conducted an experimental learning programming class for the visually impaired using P-CUBE and got various opinions for P-CUBE. In this paper, we report the system configuration of P-CUBE, programming class of workshop for beginners and visually impaired, and proposed a system of transferring data to the mobile robot based on these opinions from participants.

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