Abstract:

This paper presents a fuzzy control system for an urban junction adopting fixed phase orders and multiphase. The traffic flows in the next cycle may be estimated, and the maximum time of green light is adjusted dynamically. Each phase time is determined according to traffic urgency degree of the current phase and the next phase. Through imitating the ways of traffic police managing the traffic, this signal control strategy has the ability of intelligently controlling the light signals according to the real traffic flow. Using genetic algorithm to modify fuzzy membership functions, the system can change its membership functions adaptively to an optimal setting in different traffic situations. A simulation experiment at intersection is performed and the performance is measured with average vehicle delays through the intersection. Simulations result shows that the fuzzy control system can effectively decrease the average delay time in the intersection and is superior to the conventional method. The strategy can deal with more stochastic and more uncertain traffic flow.

Key words: traffic flow;multiphase;fuzzy control;genetic algorithm;optimization