Global output feedback control for a class of general nonlinear systems with input matching uncertainty

Abstract

This paper is concerned with the global stabilization problem via adaptive output-feedback for a class of uncertain nonlinear systems. Different from the closely related literature, the system under investigation possesses input matching uncertainty and the unknown constant multiplied by the polynomial of output-input growth rate. To solve the problem, an extended state observer is constructed by introducing dynamic high-gain to effectively counteract the negative effects of input matching uncertainty. Particularly, only one dynamic gain is introduced to deal with the serious unknowns and the polynomial of output-input in the growth rate. Based on the high-gain observer, an adaptive output-feedback controller is designed to make all the states of the closed-loop system globally converge to zero. A numerical example is provided to illustrate the effectiveness of the theoretical results.