Fuzzy Active Disturbance Rejection Control for Direct Driven Exoskeleton of Swing Leg

Abstract

To obtain a better control of the direct-driven exoskeleton (DDE), a fuzzy active disturbance rejection control (FADRC) is proposed to deal with the uncertainties and unknown disturbance in this paper. The dynamic model of the DDE during the swing phase was constructed and decoupled at first. Then a FADRC was built for the exoskeleton of the swing leg. To validate the feasibility of the proposed control strategy, the simulations were carried out with comparisons to the traditional active disturbance rejection control (ADRC) and proportion-integration-differentiation (PID) control. The results showed that the FADRC and ADRC were better than PID with a higher response and lower tracking error to the desired value, and also FADRC can relieve some chattering phenomena with lower torque compared with ADRC. With the presented FADRC, the DDE is able to follow the desired trajectory with a good tracking performance, strong anti-interference ability and lower driving torque.