Research On Dynamic Timing Of Direction Indicator Signals Based On The Proportion Of Road Traffic Flow

As the place where the urban road traffic is gathered and dissipated , it is an important part of the urban road, which plays a very important role in the road network.The traditional city traffic signal timing control is mostly using the timing control method to design the traffic signal timing scheme, sometimes it is considered that divided into several control periods according to the significant difference of the whole day traffic volume.No matter which scheme does not consider the randomness of traffic flow.The timing scheme of the traffic light is fixed at the same time and interval,it is difficult to adapt to the situation of the obvious fluctuation of traffic flow, which is often causing traffic jam or green space in the actual intersection.In this paper, the existing methods of signal timing optimization are summarized and analyzed,summarize the advantages and disadvantages of various methods and the applicable conditions,aiming at the disadvantages of the existing traffic signal timing control strategy, this paper proposes the idea of dynamic timing of direction indication signal based on the proportion of road traffic volume:At first,this paper defined the proportion of road traffic volume from the source and destination point,and made a detailed analysis of road traffic volume destination composition.And expounded the influence of the proportion of traffic volume on the direction indication signal intersection timing.According to the characteristics of traffic flow and its turning characteristics,and based on the detailed comparative analysis of short-time prediction method on common traffic flow.useing the ARIMA model to forecast the proportion of road traffic volume.Then, according to the forecast value of the proportion of the traffic volume of each section,the paper puts forward the initial judgment method of real time intersection phase scheme based on the intersection vehicle delay.And Webster timing method is introduced and analyzed in detail,in view of the fact that it can not adapt to the real-time change of traffic volume and may cause the waste of road resources,amending the two phase distribution formula base on the traffic volume proportion,and obtaining the two phase direction indicator dynamic timing method.Then,based on the considering of the symmetry of the opposite import road traffic volume proportion,the adjustment strategy and dynamic timing formula under different intersection phase schemes are given,and the strategy and principle of dynamic adjustment of intersection direction indication signal is given.Finally, the actual intersection in Chengdu which is using the Webster timing method was investigated,using Eviews software to establish the ARIMA model of the proportion of traffic volume of each section of the intersection,fitting the survey data to predict the value. According to the predicted value judging the phase scheme in real time,calculating the dynamic timing results of the direction indication signal at intersections,giving the green light time adjustment strategy for each direction indication signal of each entrance road.And the feasibility of the proposed method is compared with Webster timing scheme from three aspects:operating factor of green time?intersection delay and traffic capacity .To verify the effectiveness of the method proposed in this paper.