Research On Intelligent Timing Model Of Traffic Light

At present, traffic signal fixed cycle control method, that the traffic signal lights in accordance with the predefined fixed period and the predefined phase to work, is still used in most areas in China as the control method of the traffic signal lights. It’s suitable to implement to the situation that the traffic flow and traffic type area is predictable. However with the city developing, the way of timing control mode can not meet and adapt to changes in short-term fluctuation of traffic flow. Some of its improvement way is just make the traffic light cycle simply divided into peak period and general period, which is not real time. So when the traffic flow shifts obviously. Will cause serious traffic delays. Can not adapt to real-time traffic conditions change, will not only cause the waste of time, but also brought the corresponding economic problems, environmental problems.Firstly,the internal and abroad research working present situation and existing problems are introduced in this paper.Secondly, related basic conceptions, basic theory and basic method of establishing the traffic signal control model is introduced. The definitions like traffic signal control parameters (signal cycle, the green signal ratio, etc.), raffic flow parameters (saturation flow, capacity etc.) and parameters of the evaluation of road traffic quality (delay time, number of stops) are also introduced.Then, single intersection signal control is studied, mainly analyze the timing control and induction control.Next, the traffic signal timing mathematic model is established. Considering conveniences and stability of the experimental data, queue length is set as the reference index. After comparing conventional vehicle detection, loop detection technology and video vehicle detection technology are selected to collecting data. In the model, key flow is used to determine the selection of traffic intersection, on condition that the traffic phase and cycle time are not changed, just adjust the green light time in each phase, to minimize the whole intersection delay time and make the traffic queue length in each direction relative balanced. And this model is verified with a T intersection traffic flow situation. At last, the model algorithm flow is described.Thirdly, comprehensive comparison of several common traffic simulation software, choose the VISSIM simulation software for traffic flow simulation, According to the model algorithm process to adjust the traffic signal control, through two experiments to test and analyze the result, to verify the feasibility of this model algorithm process in traffic signal control, and also to analyses its produced economic and environmental benefits.Finally, we carried on the summary to the work. inadequacy and can improvements are also discussed.