A dual‐observer design for global output feedback stabilization of nonlinear systems with low‐order and high‐order nonlinearities

Abstract This paper employs a dual‐observer design to solve the problem of global output feedback stabilization for a class of nonlinear systems whose nonlinearities are bounded by both low‐order and high‐order terms. We show that the dual‐observer comprised of two individual homogeneous observers, can be implemented together to estimate low‐order and high‐order states in parallel. The proposed dual observer, together with a state feedback controller, which has both low‐order and high‐order terms, will lead to a new result combining and generalizing two recent results (Li J, Qian C. Proceedings of the 2005 IEEE Conference on Decision and Control , 2005; 2652–2657) and (Qian C. Proceedings of the 2005 American Control Conference , June 2005; 4708–4715). Copyright © 2008 John Wiley & Sons, Ltd.