Development of rehabilitation support system for reaching exercise of upper limb

Form the social need for aging the rehabilitation robot will be expected to become one of the most significant application fields of robotics. Although many researches have been reported in this field, there have been only a few cases of the application for the upper limbs. From these backgrounds, we have been developing a rehabilitation support system for reaching exercises of the upper limb motor function. In this paper, we introduce the rehabilitation support system, which we have developed. In this system, the exercise for the subject is accomplished as follows: A subject grasps the grip. The grip and a tracing pattern are shown on the display. Then, the subject is instructed to move the grip so as to trace the pattern while watching the display. During this operation his/her traces that are off-trace are corrected to the desired pattern by the aid of servomechanism. This function is called a motion assistance function. Through this exercise, the subject is expected to increase the reaching ability and to acquire the stable reaching motion. In order to realize this function, we proposed a control method is based on impedance control. In order to confirm the effectiveness of the proposed control method, we applied the proposed system to a healthy student before applying it to patients. Some basic experimental results show that the proposed motion control is effective to achieve the reaching exercise.