Hierarchical intelligent control and coordination of urban traffic management systems

On the basis of analyzing the present urban traffic management systems in China, this paper presents a hierarchical intelligent control and coordination conceptual architecture of urban traffic control system and urban traffic guidance system, which are two dominant and efficient traffic management systems. The technique expects to be much easier for deployment. In the primary coordination of fixed timing control for different time of the day and outdoor guidance system, the paper suggests the signal timing parameters should be regulated in a week interval according to statistical intersection delays, and the guidance information should be explicit traffic condition estimation with fuzzy matching from congestion measurement of links and intersections. Further more, the higher coordination mechanism of adaptive signal control and in-vehicle route guidance is also put forward, a system optimum equilibrium flow model is described with minimizing the total delay of the road networks, getting optimal traffic volume on a link, then calculating the signal timing parameters and optimal route so to make full use of road network resources and realize efficient transportation.