Robust impulsive reset observers of a class of switched nonlinear systems with unknown inputs

This paper is concerned with observer designs for a class of switched nonlinear systems with unknown inputs under average dwell time (ADT) switching. Firstly, for the unknown input (UI) elimination purpose, an output derivative-based method is considered. Then, in order to avoid using differentiator signals and meanwhile maintain a satisfactory estimation performance, a full-order impulsive reset switching observer is developed. The existence condition of such an observer is given via a Riccati equation. Besides, we also devote to the construction of the reduced-order observer. And furthermore, it is found that the condition under which a full-order observer exists also guarantees a reduced-order reset switching observer. Finally, a switched nonlinear electronic circuit system is used as the simulation example to verify the effectiveness of the obtained methods.