Modeling and Supervisory Control of a Railway Signaling Systems Using Color Petri Net

Modeling and simulation are widely used in the transportation network. In fact, by using this technique, a pre-built system will be analyzed after and before launching. Petri nets are useful tools for modeling and analyzing complex networks such as railway network. In this paper, using colored petri net concept, the main elements of a railway track and signals is modeled including turn out, track segment, end segment, junction and etc. In this model, the place is intended as block similar to railway and to show that block is busy by train, it is used the arc to each place. The supervisory control is designed to supervise train input and output to yards and stations, safety and non-blocking requirements in such a way that not only proposed railway network is not blocked but also safety is guaranteed. In this regards, some arcs is intended whose conditions have the role of supervisory control and also Normal and Express trains are considered in railway network as color token in petri net model. It is analyzes the petri net model by CPN Tools to satisfy logical (safety and non-blocking) and operational requirements of network. So Availability Tree is provided by state space graphs results to verify non-blocking in train operations and satisfying safety requirements. Then Best Integer Bounds Analysis is provided to verify safety operation requirements in signaling railway blocks. Finally The Best Upper Multi set Bounds Analysis in CPN Tools is implemented to verify the maximum number of Token(Train) detection in each place (block) in order to verify that the express train is never guided to waysides.