Design and Analysis Urban Traffic Lights Using Timed Colour Petri Nets

In this paper, we propose a method called timed colour Petri nets (TCPN) in modeling a sophisticated urban traffic light control system for nine crossroads. The variation of a vehicle´s direction in the crossroads is allowed two-phase, six-phase, or eight-phase transitions for each different crossroad. To our knowledge, this is the first work that employs TCPN to obtain the model of the urban traffic signal control system. The first feature of the model concerns when one direction has a green light. In the eight-phase translation process, right turns are allowed under a red light in the perpendicular direction. Second, the indication displays at each crossroad can be explicitly observed. Third, the time colour feature of the employed Petri nets enables the compactness and explicit interpretation of the system´s structure. With these features, the liveness and reversibility of the model for the urban traffic signal control system is verified