Mixing sliding mode and linear differentiators for 2nd and 3rd order systems

International audienceHigh-gain observers and sliding mode observers are two of the most common techniques to design observers (or differentiators) for lower triangular nonlinear dynamics. While sliding mode observers can handle bounded nonlinearities, high-gain linear techniques can handle global Lipschitz nonlinearities. In this preliminary paper, we present a novel observer design for second and third order systems which benefits from both techniques. More precisely, the proposed observer converges in finite-time and handles nonlinearities satisfying an incremental affine bound