Research On Urban Intersection Real-time Control Method

Our country has entered a rapid development high level of urbanization and city motorized, there are almost 800 big or middle cities that get into traffic jam. And traffic congest is the most important problem that restricts the improving of citizen life. The most effective method of solving traffic congestion in the urban is creating and using advanced traffic control system. Traffic signal control is the kernel of traffic control system. Because of above all, this thesis analyses control methods of conditional intersection signal timing, and researches adaptive traffic signal control method.First, I discuss the theory of traffic flow, and introduce basic definition, performance target, traffic signal classification of traffic signal control.Secondly, this thesis deeply analysis Fix-timing control method and actuated control method, and discuss the advantage and applicable field of two signal control methods. Then, It presents a new real-time traffic flow prediction method, based on this method, this thesis give out two adaptive traffic signal control method: one is based on Genetic Algorithm; another is based on Dynamic Programming.At last, this thesis carries out simulation on the SUMO which is an open source micro traffic simulation system of German Aerospace Centre. It compares all the signal control methods presented above and analysis their applicability. The simulation result indicates that: under the middle congestion of traffic flow, the signal control methods based on adaptive traffic control has better performance than other methods, and they reduce from 13.26 percent to 40.64 percent vehicle delay in average, this is because the adaptive traffic signal control methods can response to the change of traffic flow neatly. But when the traffic flow increases to heavy congestion, also means over saturation, none of the signal control methods presented above could get good performance, all of the control results are close to Fix-timing control method. In this condition, prolong the time of signal cycle is a good method.