Output Tracking of Nonminimum-Phase Systems via Reduced-Order Sliding-Mode Design

In this paper, a method to design the reduced-order sliding-mode control is proposed for the robust output tracking of an arbitrary signal for nonminimum-phase systems. The main contributions in this paper include the design of the reduced-order switching function that ensures the asymptotic tracking of an arbitrary reference signal during sliding motion, the design of the reduced-order sliding-mode controller that enforces the sliding motion in finite time, and the computation of bounds on stable and virtually stable zero dynamics that is required for the output tracking. To show the effectiveness of the proposed design method, results of implementation on the experimental setup of an inverted pendulum system are also presented here.