Robust tracking and disturbance rejection in nonlinear systems

This paper presents a self-contained treatment of the robust nonlinear servomechanism theory: an extension of the robust linear servomechanism or structurally stable output regulation theory to the nonlinear setting. Existence conditions for the state feedback robust controller are presented first. Then a characterization of the minimal polynomial of an augmented exosystem is given. This characterization leads to a straightforward procedure to synthesize a k/sup th/-order robust servo-regulator.<>