Traffic Signal Optimization Control Based On Improved Cell Transmission Model

With the accelerating process of urbanization,the traffic demand is increasing,which leads to the gradual aggravation of traffic jam in urban road.As the crosspoint of road,the intersection is the location of vehicle aggregation and steering.The traffic characteristics of intersection are usually complex and traffic accidents are easy to happen,which make intersection becomes the bottleneck of traffic flow in urban road network.As the main control mode of intersection,traffic signal control is the key to solve the urban traffic congestion.Reasonable traffic signal control can effectively improve the capacity of road traffic.This paper first introduces the basic theory and method of urban traffic signal control,analyzes the traffic flow characteristics of urban signalized intersection,and then elaborates the traffic flow model commonly used in traffic management-Cell Transmission Model.To make the traffic flow model can capture and describe the dynamic characteristics of more complex traffic flow while maintaining good computational efficiency,an improved Cell Transmission Model is proposed considering the difference between different types of vehicle length in this paper,which makes the model more practical.A diversion model of channelized area is established based on the improved Cell Transmission Model.Taking the average delay of vehicles as an optimization objective,a signal timing optimization model for intersection is established.Finally,taking two intersections with different states as the research object,the Bees Algorithm is used to dynamically optimize the signal timing scheme,and the simulation is carried out by MATLAB.The results show that the dynamic optimization method can respond to the change of traffic flow in time and can effectively reduce the average delay of vehicles at the intersection under unsaturated and saturated conditions,and has better control effect in saturated condition.