Sliding Mode Control of a Power Screw Driven Positioning Table

Precise positioning and trajectory tracking control applications are important for industrial manufacturing and scientific research. Ball-screw, worm-gear, and power-screw driven systems are widely used for this purpose. Since power screw driven systems provide long range and allow precise servo control, they are commonly preferred. The control strategy developed for power screw driven systems is expected to be robust, to respond rapidly for fast tracking performance and to reject disturbances. These systems should also be controlled precisely in case of uncertainties. In order to enhance the overall system controllability, sliding mode control is one of the preferred strategies. In this paper, sliding mode control strategy developed for a power screw driven positioning table is introduced. Mathematical models of the power screw, positioning table and actuator subsystems are derived. An experimental positioning table setup consisting of a power screw is manufactured to which the developed controller is deployed for testing. The stability of the sliding mode controller is investigated in detail and its performance is compared to that of a PID controller for verification purposes.