Recently, the research on finite-time observers for nonlinear systems has made great progress [1, 2, 3]. However, some of these observers are not continuous such as sliding mode observers. The continuity property and its importance in finite-time stability are realized in [4, 5]. It is also interesting to point out that continuous observers are realized to be different and unique in the nonline...

This paper introduces a new approach to output feedback stabilization of SISO systems which, unlike other techniques found in the literature, does not use quasi-linear high-gain observers and control input saturation to achieve separation between the state feedback and observer designs. Rather, we show that by using nonlinear high-gain observers working in state coordinates, together with a dyn...

Bilinear systems offer a promising approach for nonlinear control because a broad class of nonlinear problems can be reformulated and approximated in bilinear form. System identification is a technique to obtain such a bilinear approximation for a nonlinear system from input-output data. Recent discrete-time bilinear model identification methods rely on Input-Output-to-State Representations (IO...

This paper presents a comparison study of performances and characteristics of three advanced state observers, including the high-gain observers, the sliding-mode observers and the extended state observers. These observers were originally proposed to address the dependence of the classical observers, such as the Kalman Filter and the Luenberger Observer, on the accurate mathematical representati...

This work studies the problem of design of discrete-time nonlinear observers in the presence of exogenous disturbances. In particular, the present work proposes a systematic design method for discrete-time nonlinear state and disturbance observers in modular form, consisting of an observer for the disturbance-free part of the system, along with a disturbance observer and a stateestimate correct...

In this article, we propose a new approach to design globally convergent reduced-order observers for nonlinear control systems via contraction analysis and convex optimization. Despite the fact that is concept naturally suitable state estimation, existing solutions are either local or relatively conservative when applying physical systems. To address this, show problem can be translated into an...