Hybrid observer for switched linear systems with unknown inputs

This paper addresses the state estimation of a class of switched linear systems with unknown inputs. These systems may have modes in which the state is not fully observable. A time-varying state transformation allows to implement a suitable reduced-order observer. This observer is based on gathering partial information from individual modes of the switched system. The asymptotic state reconstruction is guaranteed in spite of the presence of unknown inputs. Some simulations highlight the efficiency of the proposed observer.