Repetitive control for the periodic walking training in a gait rehabilitation robot

AbstractThe number of people with difficulty in walking has increased with aging issues worldwide. It is possible to regain walking ability after persistent locomotion training. With the development of robotics, cyclic walking motion is implemented to stimulate the correct walking pattern. In order to better track the planned walking motion, this paper focuses on the “repetitive” motion input for the lower limb, and the intelligent control algorithm is proposed to diminish the tracking error. Repetitive control algorithm, based on the characteristics of a cyclical input signal and the internal model control principle, implanted the periodic signal generator has developed into the closed-loop system in order to achieve steady tracking of cyclic reference signals and rejecting disturbance on the rehabilitation robot. Results are applied on the simulation model of a bedecked overground walking gait system. It shows the effectiveness of the proposed method compared with the conventional PD controller.