Robust sliding mode controller design of a dual-stage actuator system for S-curve tracking

In order to provide speed and accuracy in a long-stroke precision positioning system, the Dual-Stage Actuator (DSA) design have been utilized widely in different industrial applications. This paper uses the Fast Non-singular Terminal Sliding Mode (FNTSM) controller, a known robust method, for controlling such a DSA system, applied to track a s-shaped reference trajectory. A full controller design is derived for this DSA system, and further analysis with the selection criteria of the controller parameters for the DSA improves the tracking performance over traditional PID and Non-Singular Terminal Sliding Mode (NTFS) ones. Simulation results demonstrate the FNTSM controller feasibility and verify its robustness, especially accounting the relative distance between the two actuators. An order of magnitude improvement on error and relative distance is shown when the DSA system is accelerating and decelerating on the s-shaped trajectory movement.