Isolated Intersection Traffic Signal Timing Problem: A Fuzzy Control Approach and A Case Study

摘要

Considering the randomness of the traffic flow, a self-adaptive control method for isolated intersection signal timing is proposed, which imitates the traffic police's signal controlling behaviors. Firstly, we define the concepts of Busy Level (for the phase that has got the right of way) and Urgent Level (for the other phases that have not got the right of way). Based on the definitions, the signal control method is put forward, which can be summarized in brief that when Urgent Level is greater than Busy Level, the phase with the highest Urgent Level gains the right of way. Then, based on the fuzzy control theory, we elaborate the fuzzy modeling process of Busy Level and Urgent Level and put forward an optimization method of the membership function using the traversing method. The proposed method is a breakthrough comparing with the old methods that optimize the circle time, the split or the amount of the green time extension. The method has the charactaristics of no fixed circle time, no fixed phase sequence and is more effective to suit the fluctuant traffic flow. At last, the computational results of an simulation demostrates that the proposed method is far more effective than the pretimed signal timing methods.