Model-Prediction Based Terminal Sliding Mode Control for Biped Robot with External Disturbance

To solve the tracking problem of biped robot with external disturbance and internal parameter uncertainty, this work proposes a hierarchical control algorithm on the basis of observer sliding mode control combined with model predictive control. Disturbance observer and model predictive control are introduced to compensate the disturbance signal and the uncertainty of internal parameters and to optimize the reference trajectory, respectively. Aiming at the chattering problem existed in sliding mode control, a new approach law is utilized to design the sliding mode control law, which is verified by Lyapunov candidate function. The simulation results show that on the premise of ensuring the stability of motion, presented control method can not only weaken the chattering problem, but also overcome the influence of external interference and modeling error.