Higher‐order sliding‐mode observer for state estimation and input reconstruction in nonlinear systems

Abstract In this paper, a higher‐order sliding‐mode observer is proposed to estimate exactly the observable states and asymptotically the unobservable ones in multi‐input–multi‐output nonlinear systems with unknown inputs and stable internal dynamics. In addition the unknown inputs can be identified asymptotically. Numerical examples illustrate the efficacy of the proposed observer. Copyright © 2007 John Wiley & Sons, Ltd.