Design of Fuzzy-PI Controller for Shoulder Exoskeleton with Motoric Progress of Rehabilitation Subject Consideration

Abstract

Exoskeleton robot can be effective in assisting or restoring paralyzed motor functions caused by stroke. The controller performance of the exoskeleton influences the rehabilitation process. For this reason, in this study, a fuzzy-PI controller system was developed to control the speed and position of the shoulder exoskeleton. The rehabilitation scheme given is flexion-extension and abduction-adduction of the shoulder. Target of ROM is sinusoidal trajectory based on the ROM that can be reached by rehabilitation subject. The optimal Kp value for position control is 9000 and the optimal Kp value for speed controller is 2000. The optimal Ki value for speed control is 100. The addition of a fuzzy-PI controller can reduce the overshoot rate up to 3.8% and reduce the rise time up to 22.2%. The RMSE of position after the application of fuzzy-PI controller is 0,0018°.