Robust Adaptive Dynamic Surface Control of Multi-link Flexible Joint Manipulator with Input Saturation

This paper investigates the tracking control for multi-link flexible joint manipulator system with disturbance, uncertain stiffness and input saturation. A robust adaptive dynamic surface control scheme is developed with an auxiliary dynamic system. The auxiliary dynamic system is employed to handle input saturation. To compensate for disturbance, an adaptive law for disturbance upper bound estimation is designed. The value of uncertain stiffness is updated by another adaptive law. It is proved that the proposed control scheme can realize precise tracking of link angles and guarantee the uniform ultimate boundedness of all the signals in the closed-loop by appropriately choosing the parameters to be designed. Finally, simulation results demonstrate the effectiveness of the proposed control method.