Based On The Video Saturated Traffic State Single Intersection Signal Control Method Research

Along with the development of economy and society, the number of vehicles in city increases rapidly, which results in urban transport growing rapidly and often under the saturated traffic condition, especially in rush hour. So traffic congestion is inevitable. It not only reduces travel efficiency and adds travel time, but also brings a series of issues such as economic loss and environmental pollution. Intersection is the point of urban roads, where is also most likely to be under saturated traffic state and traffic congestion. If traffic congestion (traffic state recognition) in road network is able to be detected in time, organized and coordinated effectively by appropriate signal control, which will help to reduce traffic time of traffic congestion and prevent the crowded from further spreading. Therefore, it is necessary for the intersection traffic state recognition and signal control method to be in-depth researched. In this paper, the above two problems were studied.(1)On the base of definition of others, this paper draw a conclusion that detecting saturation flow combined with testing the moment of vehicles through the upstream and downstream junction will be able to detect whether there are the second line up of vehicles, that is, whether the intersection is in saturation(2)This paper proposed a hierarchical fuzzy control method based on traffic demand intensities. This method divided all phases into two types:red light phase and green light phase. The traffic demand intensities of the red light phase is characterized by the occurrence of traffic deadlock urgent and traffic busy degree, traffic demand intensities of the green phase is characterized by traffic busy degree. Then the right of priority is assigned to the phase which’s traffic demand intensities is largest. Which not only traffic deadlock is avoided, but also the right of priority is assigned to those phase most prone to traffic congestion.(3)Finally, simulations of timing control and fuzzy control two methods in the same flow state have been made respectively by software which was developed by vb.net. The simulation results show that fuzzy control method in this paper can dissipate traffic congestion as soon as possible relative to timing control and is more suitable for signal control of single intersection in the saturated traffic state.