Improved sliding mode control based on disturbance observer for robot assisted surgery training

Abstract

The traditional sliding mode control has high robustness for the trajectory tracking of manipulator, but the output of the controller will have large jitter. To overcome the shortcomings of traditional sliding mode control, this paper proposes a novel sliding mode control scheme (DOB-PD-SMC) based on disturbance observer and proportional differential to realize robot assisted surgery training. Disturbance observer is used to estimate disturbance. The combination of disturbance observer and traditional sliding mode control can reduce the output jitter of the controller. PD control ensures that the system can quickly track the standard reference trajectory. The Lyapunov equation is used to prove that the method is stable in the surgical training system. The simulation results show the effectiveness of the scheme.