Backstepping Sliding Mode Control for Robot Manipulator via Nonlinear Disturbance Observer

A kind of backstepping sliding mode control method is presented for the nonlinear, uncertainty and strong interference manipulator system via nonlinear disturbance observer. Firstly, combining sliding mode control algorithms with backstepping technique, a backstepping sliding mode position tracking controller is developed. Secondly, a nonlinear disturbance observer is designed for the existed disturbance in manipulator system, which can compensate for backstepping sliding mode position tracking controller. Stability analysis of closed loop system is given by Lyapunov stability theorem. Finally, the system simulation results of sliding mode control and backstepping sliding mode control are given respectively. The simulation comparison shows that the presented control method improves the position tracking control accuracy of the manipulator.