Output regulation of nonlinear systems by sliding mode

This paper focuses on the design of an output feedback sliding mode regulator able to achieve the asymptotic tracking of a reference trajectory for nonlinear systems. It is assumed that the reference trajectory is generated by means of a neutrally stable unforced system (exosystem) whose state is known. The design methodology is based on the center manifold theory and on the "equivalent control" concept and can be applied to both minimum and nonminimum-phase systems. (C) 2001 Elsevier Science Ltd. Ail rights reserved.