A Filtered Switching-Type Sliding-Mode Backstepping Control Approach for a Piezopositioning Stage

This paper presents a filtered switching-type sliding-mode backstepping control (FSTSMBC) approach for precise trajectory tracking of a piezopositioning stage. First, a dynamics of a mechanical motion system with the dynamics of hysteresis is constructed to represent the motion dynamics of the piezopositioning stage. Then, to simply represent the hysteresis dynamics, an approximation function is developed. From the constructed dynamics with the approximated hysteresis function, the FSTSMBC approach for the trajectory tracking is developed. By using the FSTSMBC approach, the trajectory tracking system of the piezopositioning stage possesses the features of a high-precision tracking performance, robustness, and effective chattering reduction compared to the results of using the traditional sliding-mode control. Experimental results of the time responses from the computer-controlled one-dimensional piezopositioning stage are illustrated to show the validity of the proposed control approach for practical applications.