On second-order sliding mode observers with residuals´ projection for switched systems

This paper outlines some results concerning the application of second-order sliding mode techniques to address the problem of simultaneous discrete and continuous state reconstruction for linear autonomous switched systems. A stack of dynamical observers produces suitable residual signals which are used for reconstructing the discrete state and, at the same time, for identifying the unique observer that provides an asymptotically converging estimate of the continuous state. Simple tuning formulas for the suggested schemes are constructively developed along the paper by means of appropriate Lyapunov analysis. The main result and most significant novelty of this work is a projection procedure for deriving residuals characterized by finite-time convergence. Simulation results confirm the effectiveness of the proposed approach.