Intelligent Control Theory In The Traffic Control System

At present, the best way to solve the contradiction between the slow-increasing basic traffic establishment and the fast-increasing number of vehicles is to found a well-worked Intelligent Transportation System (ITS). Intelligent Transportation Control System (ITCS), as a part of ITS, plays a very important role, and many productions have been obtained. Some control mechanisms based on mathematic model and traditional control methods were established, and the results turned out to be good when traffic was not congested. However, when traffic flow grows heavier and heavier, the limit of the performance of traditional traffic control system is challenged over and over again, then it is urgent to introduce new techniques into this field.Intelligent Control theory is the combination of Automatic Control theory and Artificial Intelligence theory, and is suitable to control the uncertain, complicated target, which is hard to found an accurate mathematic model. So this is why Intelligent Control theory can be applied to ITCS efficiently.Fuzzy Control, as an important Intelligent Control method, also preserves that characteristic, for it's control rules are abstracted from the practical experiences, and are described by natural languages, just as men usually do in their minds. As a result, ITCS based on Fuzzy Control developed rapidly.This paper proposes a new coordinate control algorithm of urban main road to solve some problems of traditional algorithm, such as the randomicity of the arriving vehicles, the speed changing of the vehicles on main road, the discrete phenomena of the traffic flow and the arriving vehicles on the secondary road. This new algorithm applies improved fuzzy control algorithm in each intersection to increase the efficiency of the green time and reduce the traffic delay; meanwhile, interrupts the fuzzy controller, as long as mass vehicles are coming from the main road; therefore, realizes the coordinate control on the urban main road. The simulation indicates that the new algorithm can improve the traffic condition of the whole road successfully.Actually, it is always a difficult problem to abstract fuzzy rules and select membership functions. Some scholars considered that introducing certain other...