Control of large-scale urban traffic networks using hierarchical hybrid automata

Urban traffic network is a typical example of a complex system called hybrid dynamic system (SDH). Although hybrid automata (HA) is a popular formalism in modeling, analysis and controlling SDH, the HA model of large scale urban traffic network gets substantially complicated for analysis and control due to large dimensionality of such systems. To overcome this problem, a new hierarchical control structure for large network based on HA is investigated in this paper. This technique divides the complex control problem of a large traffic system into different levels. The proposed control technique has been tested for an urban traffic network of four intersections under different traffic conditions. The experimental results are compared with those from Synchro (version 8). Simulation results affirm the improvement and the effectiveness of the proposed approach.