An intelligent control for crossroads traffic light

Based on analyzing the current situation of urban traffic signal control, Graph Theory and Fuzzy Control system for single intersection that consists of seven phase and three lanes are designed in this paper. This can be flexibly operation based on real-time traffic flow. First, we use Graph Theory to analyze the traffic flow of a variety of intersections, which is plain and simple. However, because of the lower availability for complex intersection, the other method Fuzzy Control is adopted in the paper. We can obtain the vehicle number of each lane through the sensor, and prescribe the maximum number of vehicles that phase traffic highest priority. It will turn to the highest priority phase when it transferred from the previous phase to the next. By fuzzy rules, namely fuzzy inference, which is adapted to the current queue length and traffic queue length, has the best green delay time. The simulation results show that the control of delay time in vehicles is improved by using fuzzy control method compared with the traditional control of time-fixed.