Communications in Information and Systems
Volume 15 (2015)
Global robust adaptive output regulation for nonlinear systems of relative degree up to two
Pages: 15 – 33
In this paper, we study the global robust output regulation problem for an uncertain nonlinear lower triangular system subject to an uncertain exosystem. Under some standard assumptions, the problem can be transformed into a robust adaptive stabilization problem of a well defined system called augmented system. In order to deal with the unknown parameter of the exosystem, we construct an internal model consisting of two dynamic compensators. As a result, the augmented system contains both the static and dynamic uncertainties and the dynamic uncertainty is not input-to-state stable. Then, we develop a recursive approach to construct the controller.