Dynamic Observer for Nonlinear Uncertain Systems: Applied to Vehicle State Estimation

Abstract

This paper presents an approach to design a dynamic observer (DO), ensuring the robust state estimation for a broad family of uncertain nonlinear systems under unknown inputs and disturbances. Toward this objective, it initially introduces the error variable to obtain the state-space model of estimation error. Then, by exploiting the algebraic conditions, the determination of the parameter matrices of the proposed DO is simplified. Furthermore, by using the bounded real lemma, the problem is reduced to the optimization of linear matrix inequality (LMI), which can limit the negative influence of disturbances. In the end, an example is employed to illustrate the performance of the proposed observer.