Observer-based tracking controller design for a class of Lipschitz nonlinear systems

Abstract

In this paper, the observer-based controller design problem for tracking a constant reference input in Lipschitz nonlinear systems is addressed. To this end, at first, a state feedback controller is proposed and sufficient conditions for solvability of the problem are obtained in terms of linear matrix inequality feasibility conditions. Then, it is shown that for the considered Lipschitz nonlinear system, the separation principle holds and the estimation state variables can be used instead of the state variables. Subsequently, an observer for estimating the states of the system and also an observer-based controller is designed. Simulation results on a flexible link are given to verify the effectiveness of the proposed controller.