Reduced order state estimation for a class of impulsive switched systems with unknown inputs.

This paper introduces a robust method for estimating states and switching signals in impulsive switched systems with unknown inputs. It uses a reduced-order estimator to handle inaccessible states and an output derivative-based method to address the effects of unknown inputs, even though this adds some impulsive effects. The method is divided into two main steps: first, dedicated estimators determine the switching signal and identify the active subsystem; then, state estimation is carried out. By incorporating the estimated switching signal, the method effectively eliminates impulsive effects caused by unknown inputs. The study also explores the key conditions needed to ensure that estimation errors decrease exponentially. It uses a common Lyapunov function and Linear Matrix Inequality techniques. Simulation results show that this method is both efficient and effective, outperforming single-estimator approaches.