A haptic feedback system is required to assist telerehabilitation with ro-bot hand. The system should provide the reaction force measured in the robot hand to an operator. In this pa-per, we have developed a force feedback device that presents a reaction force to the distal segment of the operator’s thumb, middle finger, and basipodite of the middle finger when the robot hand grasps an object. The device uses a shape memory alloy as an actuator, which affords a very compact, lightweight, and accurate device.

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Numerous researches have been carried out to use robot in the area of stroke rehabilitations. The conventional approach is to assist patient to perform Activities of Daily Living (ADL) through a set of pre-programmed trajectories. The main drawback lies in the lack of voluntary movement by the patient. Many of these works have been carried out by using positional feedback control. In this kind of system, it is difficult to assess patient’s muscle condition, which may results in inconveniences due to torques or forces asserted by the rehabilitation robot. The main aim of the project is to build a stroke rehabilitation system using socially inspired robot technique. The system monitors patient’s muscle activity and uses this information to drive an exoskeleton robot that will assist patient to his/her arm. Movement is generated based on voluntary muscle activity by patient and therefore will improve their learning curve. Another main advantage is the system minimizes patient’s inconveniences due to movement by robot. The system is based on torque feedback control. A sliding mode control was implemented in replace of conventional control. The main advantage of sliding mode control over conventional control is its robustness. Sliding mode control does not require precise mathematical model of the system and it is insensitive to parametric changes and uncertainties within the system.

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Augmentation of human power is an important problem in the design of human assist devices such as an exoskeleton system. The overall system consisting of a human and an assistive device is a parallel control system that includes two controllers: the human brain and the assistive device controller. It has been postulated in a previous work that the motion control system of a human is regarded as a feedback control loop that consists of the brain, muscles, and the dynamics of the extended human body, and that the brain function is modeled as a control algorithm amplified by a fictitious gain. The fictitious gain compensates for characteristic changes in the muscle and dynamics. If the human is physically impaired or subjected to demanding work, the fictitious gain is increased to assist the human. The assistive device is controlled to augment human power, the amount of which is equivalent to the one attained by the fictitious gain. This paper presents the design and verification of an assistive device for elbow joint and the controller for the device based on the fictitious gain concept.

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This paper presents the design, and performance of a high fidelity three degree-of-freedom wrist exoskeleton robot, for neuroscience study, training and rehabilitation. The IIT-Wrist is intended to provide kinesthetic feedback during the training of motor skills or rehabilitation of reaching movements. Motivation for such applications is based on findings that show robot-assisted physical therapy aids in the rehabilitation process following neurological injuriesIn the present paper the IIT-Wrist haptic robot is described in terms of kinematics and haptics features to meet specific requirements for a safety human.machine interaction. In relation with a feasibility study in the field of robot therapy a preliminary training of stroke patient was perfrormed. The task consisted in tracking a target using one degree of freedom at time: Flexion/Extension, adduction/abduction, pronation/supination separately. The target motion is harmonic and tracking is aided by a suitable force field. The preliminary study with three patients shows the stability and the efficacy of the control scheme.

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In this paper we introduce the use of force feedback in conjunction with myoelectric control to establish an improved interface for a powered prosthetic limb. The force feedback is delivered through a single-axis exoskeleton worn about the elbow, while the EMG signal is derived from the biceps muscle. This combination is intended to produce a sense of effort in the biceps that is associated with the action of the motorized prosthetic gripper. The method engages both efferent and afferent signals innervating a functional muscle with the aim of realizing a muscle that is effectively biarticular. The controlling muscle spans one joint physiologically and a second, prosthetic joint functionally. Preliminary experiments have demonstrated that force feedback can substitute for vision during grasp and lift tasks.

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