Robust regulator for nonminimum phase systems by Lyapunov Redesign

In this paper we present a robust sliding mode (SM) controller for nonlinear non minimum phase systems with unmatched perturbations. Based on Regulation and Lyapunov Redesign concepts we design a suitable sliding manifold. On this manifold the perturbed dynamics are stable, namely they remain bounded whereas the output tracking error goes to zero in spite of the presence of perturbations. To enforce the SM motion on the designed manifold a super-twisting SM algorithm is used. The effectiveness of the proposed methodology is verified via a simple example.