Adaptive backstepping sliding mode control of lower limb exoskele-ton robot based on combined double power reaching law

Abstract

This paper presents an adaptive backstepping sliding mode control (ABSM) method based on the combined double power reaching law (CDPRL) for a lower limb exoskeleton robot (LLER) system. Considering the influence of robot nonlinearity, strong coupling and unknown external disturbance, the ABSM controller is designed, and the CDPRL is employed to achieve fast convergence and reducing chattering phenomenon of the sliding mode control. The experiment results show that the pro-posed method can availably weaken the chattering phenomenon, and improve the accuracy of trajectory tracking and anti-inter- ference ability in comparison with advanced and classical meth- ods.