ESO based sliding mode control for the welding robot with backstepping

摘要

This paper investigates a problem of tracking control for robotic manipulators with high accuracy. In view of the uncertainty and disturbance during the process of trajectory tracking, ESO (Extended State Observer) control is proposed to handle the uncertain factors (disturbance and dynamic uncertainty) and estimate the external torque and kinematics, respectively. Based on the combination of sliding mode control and backstepping control strategy, we design a new controller, which has strong robustness and accuracy. In term of the dynamic uncertainty in the process of trajectory tracking and considering the estimated information, the controller can guarantee the desire trajectory and the error to be zero. Lyapunov function and barbalat theorem are used to prove the global stability of the controller. During the simulation and experiment, the results show the performance of the proposed controller and the results are analysed and compared with the PID controller. The error analysis is carried out to verify the performance of the method.