Nonlinear observers for locally uniformly observable systems

Abstract. This paper deals with the observability analysis and the observer synthesis of a class of nonlinear systems. In the single output case, it is known [4–6] that systems which are observable independently of the inputs, admit an observable canonical form. These systems are called uniformly observable systems. Moreover, a high gain observer for these systems can be designed on the basis of this canonical form. In this paper, we extend the above results to multi-output uniformly observable systems. Corresponding canonical forms are presented and sufficient conditions which permit the design of constant and high gain observers for these systems are given