Robust control design for a planar humanoid robot arm with high strength composite gear and experimental validation

Abstract Aiming at uncertainties and variable loads of the robot arm, a nonlinear control algorithm is proposed. The design of the proposed control is based on the engineering practice of the planar humanoid robot arm with high strength composite gear. The proposed control, consisting of a PD control portion and a robust control portion, retains the dynamic characteristics of the system and realizes based on error. Theoretical analysis shows that the proposed control can guarantee the uniform boundedness and uniform ultimate boundedness. Based on the humanoid robot arm, the experimental validation with the proposed control is carried out and compared with the PID control. Numerical simulations and experimental results show that the proposed control can effectively deal with load changes and parameter uncertainties, and the trajectory tracking accuracy of the robot is improved significantly with the proposed control.