CoSIGN: A Fictitious Play Algorithm for Coordinated Traffic Signal Control

The problem of finding efficient coordinated signal timing plans for a large number of traffic signals is a challenging problem because of the exponential growth in the number of joint timing plans that need to be explored as the network size grows. In this paper, we employ the game-theoretic paradigm of fictitious play to iteratively converge to a locally optimal coordinated signal timing plan. Since there is only one traffic simulation required per iteration, the resulting algorithm is robustly scalable to realistic size networks modelled with high fidelity simulations. We report the results of a case study for the the city of Troy, Michigan where we experienced delay and throughput savings in excess of 10 percent for a network model of 75 signalized intersections.