A new approach to global adaptive tracking for nonlinear systems in generalized out-put-feedback canonical form

Abstract

In this paper, a new global adaptive output feedback dynamic compensator is proposed for tracking of a class of systems that are globally diffeomorphic into systems in generalized output feedback canonical form. Output-dependent nonlinearities are allowed to enter in both cases as additive and multiplicative. The system is allowed to contain unknown parameters multiplying output-dependent nonlinearities. The proposed method relies on a novel parameter estimator and state observer design methodology and the standard backstepping construction. It is shown in the paper the proposed design has three distinctive features not present in the known designs. The applicability and the effectiveness of our method are illustrated by means of respectively, a numerical example and two magnetic levitation systems which are, controlled by the coil current and the voltage applied to coil circuit.