An Approach to the Verification of Cyber Physical Systems

Cyber-physical systems (CPS) are systems that combine a physical system with an embedded information processing system such that the resulting system has novel capabilities that could not be achieved by either the physical or the computational entity alone. Reachability study has become the most basic and important challenging subject of Cyber physical systems. In this paper present a reachability analysis method of switched continuous system. According to the given faces, the new outgoing faces can be calculated and the recursive call can be continued from the new faces until all the reachable faces are found. The paper focused on reachability analysis of Rectangular Hybrid Automata model. The modeling and reachability analysis of rectangular hybrid automata is applied on a single intersection. For the case that vehicle flow show continuous behavior and traffic light exhibit discrete event behavior, a rectangular hybrid automata model of a four-phase intersection is given, in which the queue lengths are considered as continuous variables to represent the vehicle flow behavior of the intersection and the discrete event part represent the traffic light behavior. Based on the rectangular hybrid automata model all directional vehicle flows are analyzed.