New Robust Control Method Applied to the Locomotion of a 5-Link Biped Robot

This paper proposes a new design of robust control combining feedback linearization, backstepping, and sliding mode control called FLBS applied to the locomotion of five-link biped robot. Due to the underactuated robot's model, the system has a hybrid nature, while the FLBS control can provide a stabilized walking movement even with the existence of large disturbances and uncertainties by implementing smooth chatter-free signals. Stability of the method is proven using the Lyapunov theorem based on the hybrid zero dynamics and Poincare map. The simulations show the controller performance such as robustness and chatter-free response in the presence of uncertainty and disturbance.