Research On Pre-Signal Control Method Considering Bus Priority

With the rapid development of urbanization in China,the problem of traffic congestion has become increasingly serious,and public transportation priority strategy is indispensable for sustainable urban development.For urban traffic,intersections are usually bottlenecks for both private cars and buses.By utilizing the basic design concept of pre-signal based intersection,this article proposes optimal lane allocation model and signal timing model,and then generated signal priority method for buses' real time arrivals.This article introduces the design idea and operation mode of the pre-signal,and analyzes the operating mechanism of the pre-signal boosting the intersection traffic capacity.At the same time,the existing bus priority control methods are summarized from two aspects of facility design and signal control.For the traditional signalized intersections with bus lanes,there are problems such as the low utilization rate of bus lanes and the waste of space and time resources.This paper proposes an optimization method that uses the pre-signal to improve the efficiency of bus operations.Firstly,this article puts forward the optimization model of intersection lane allocation and signal timing with pre-signal based design.The model aims to solve the shortest cycle time for intersections.By allocating the amount of entrance lanes and exit lanes for different directions and optimizing the signal timing,the model can effectively improve the intersection capacity,and therefore reduce the average signal delay for cars and buses.With the pre-signal optimization model as aforementioned,this article analyzes the coordination problem between main signal and pre-signal,and analyzes the traffic delay correspondingly.Then,this article proposes dynamic transit signal priority method for presignal based intersections by using phase insertion method.Based on the method of setting the pre-signalized intersection proposed in the paper and the bus priority control strategy based on the pre-signal,this paper uses Matlab to set up the simulation environment,taking the intersection of Renmin Middle Road and Xinhua Avenue in Chengdu as the research object,using the on-site survey data and Chengdu The city's bus GPS data calibrates the simulation model.The simulation studies the three control strategies of the current control intersection,the pre-signal control intersection,and the bus priority control based on the pre-signal control.With the changes in the intersection traffic volume,bus arrival rate and other parameters,the Changes in the delay of public transport vehicles have verified the effectiveness of the control model.