Research On Intersection Signal Control Optimization Method Based On Fuzzy Control

With the rapid development of our economy and the expansion of the city scale,the car ownership rate rises sharply,and the contradiction between supply and demand of urban transportation system is becoming increasingly serious.As an important link in the urban traffic system,the intersection plays a vital role in maintaining the normal operation of the whole system.Therefore,making full use of the existing road traffic resources,improving the efficiency of the intersection vehicles,and then improving the efficiency of the entire traffic system,has become the current urban traffic problems to be solved.Based on the research of the existing traffic signal control system and fuzzy control system,this paper applies the fuzzy control algorithm to the intersection signal control to carry out real-time dynamic control of the signal light to reduce the delay of the whole intersection and the whole trunk line.The specific work is as follows:According to the five steps of fuzzy input variable,selection of membership function,design of fuzzy rules,fuzzy inference relation and fuzzy output variable,a fuzzy controller for green extension time is designed.Firstly,the queue length of the current green phase and the queue length difference between the current phase and the next phase are detected.Then according to the fuzzy rules of the fuzzy controller to determine the current green phase extension time,according to the fuzzy control algorithm designed in this paper,the intersection signal light real-time control,to achieve the purpose of reducing the intersection delay.Aiming at the problem of signal control at trunk intersections,a coordination fuzzy control algorithm is proposed,which is divided into coordination layer design and control layer design.The period fuzzy controller and phase difference fuzzy controller of the coordination layer of trunk intersections provide the common period and phase difference between intersections.The control layer of the trunk line opens the signal of a single intersection according to the period and phase difference provided by the coordination layer,and uses the fuzzy controller of green time extension to dynamically control the signal of a single intersection.The coordination layer and the control layer coordinate the control by exchanging parameters,ensuring the continuity of the whole system.Matlab is used to simulate the traffic volume of a four-phase intersection at different times,and the output of each cycle signal timing scheme under the dynamic control of the fuzzy controller in this paper,and respectively compared the intersection in the low peak period,peak period and peak period under the timing control,the classical fuzzy controller control and the green delay fuzzy controller control.The results show that the green delay fuzzy controller can change the intersection signal control scheme in real time.The control of the intersection is better than the current timing control,which can reduce the average delay of 39%;Compared with the control effect of classical fuzzy controller,it can reduce the vehicle delay by 14%.