Observability analysis of linear hybrid systems

The observability of linear hybrid system may be affected by control inputs, which include discrete and continuous control inputs. The observability of hybrid system involves initial discrete states, continuous states and discrete state switched time. The control inputs effect on system states (mainly effect on discrete states) are (analyzed.) The switching of discrete states may help to improve the observability of some linear hybrid system which is unobservable before discrete switch. And the weaker condition of hybrid system observability and rank test rules are given. An illustrative example is given at last.