Research Of Bus Priority Signal Control Of Intersection Based On Bus Bottleneck Identification

Bus priority is an important strategy to alleviate traffic congestion in large cities.According to the related research,urban intersection is still an important delay area during the bus running line.Therefore,in addition to the construction of the bus lane,how to design the bus priority signal scheme with the actual traffic conditions in China becomes to be an important research topic.The purpose of the research is to realize the bottleneck identification and related characteristic analysis based on GPS(Global Positioning System)data,which can reduce the error of bus arrival time prediction.Bus priority signal control of single intersection is proposed to apply to the bottleneck section which can reduce delay effectively and therefore improve the service level of public transport.Firstly,preprocessing the GPS data can provide suitable data for the following-up research including preliminary screening,second-screening,map matching and projective correction.Secondly,GPS data was used to define the bottleneck during bus operation and the relative indication,and then to realize the identification of the bottleneck by drawing bus trajectory map,and the temporal correlation analysis by using Origin.Thirdly,a bus arrival time prediction model was proposed based on the logarithmic normal distribution which can both consider the historical data and real-time operation parameters.Finally,a priority control method of multi-phase bus signal scheme model based on the saturation constraint is proposed,which combines with the prediction of bus arrival situation at intersection.In this model,the traffic demand of non-priority phase vehicles is considered,and the rules based on “nearest principle” are adopted to determine the priority level of arriving bus.Therefore,by adjusting the green time of each signal phase can realize the bus priority control at signalized intersection.The historical GPS location data of bus No.1 in Nanjing was took as the reseach foundation in the paper.Experimental section was selected to verify the validity of bus arrival time prediction model based on the lognomal distribution.The multi-phase bus priority control method based on the “nearest principle” and saturation constraint is verified by assuming the example.Results show that the method can reduce average delay of intersection and improve traffic efficiency effectively.