Mixed H2/Sliding Mode Controller Design for Human Swing Leg System

Humans walking seems simple, but this process is naturally complicated with extremely nonlinear dynamics as a pendulum links represent the thigh and the shank of the human. The upper body will attach to the thigh by hip, the knee will attach thigh to the shank. To acquire a complete motion of all muscles, it is required to accomplish two control actions applied at the joints. Two control approaches which are sliding mode control and H2 control are combined in this work to control the human swing leg system. The proposed mixed H2 Sliding Mode Controller (H2/SMC) is a new control algorithm conducted to give better performance than if only one of them is used. The results show that the proposed controller can effectively achieve more desirable performance and robustness.