Research On The Predicting Method Of Bus Travel Time

Bus priority is one signal timing technique that considers the bus benefits. According to information of buses and social vehicles collected by detectors, it allocates the way leave between buses and social vehicles by signal timing technique to realize its strategies. Bus signal priority (BSP) can improve bus speed and its service reliability, which can make great contributions to bus affinity.BSP concludes four aspects, which are bus information detection, bus information disposal, signal timing optimization model and signal timing scheme generation. Bus information detection and disposal are the foundation of BSP, they involve bus information demand analysis, detection methods determine, detectors location optimization and bus information transfer design. All of these have nearly relation with the architecture of priority control system and the optimization method of signal timing. Therefore, there are great significance for researching on bus information detection and disposal.At present, the research fruit about bus information detection and disposal mainly centralized on bus intelligent management, which adopts advanced bus detection technique, and predicting bus travel time between two bus stops for the electronic stops display, all the above research are one part of ATIS. But there are few results about bus information detection and disposal in the view of bus signal priority, so it can not satisfy the demand of BSP.This article analysis the information demands of every BSP pattern firstly, and then designs the architecture of bus information collection system based on the demand analysis. The collection method of bus information is one focal point in this article. By analysis the characteristic of different detectors, we design two detection methods, one is based on double loop plus identify card, and the other one is based on GPS, the design the bus information transfer channel for different bus information detection method.In the aspect of bus information disposal, it needs to provide direct information to bus signal optimization, so the bus travel time prediction from bus detector to stop line is the focal point of this article. We divide bus travel time into two parts, one is the time for waiting for green light start, and the other one is the dissipation time of vehicles in queue in front of the bus. Based on simple signal timing and considering factors such as vehicle volume of the lane, signal timing scheme, vehicle dissipation time and bus arrival time, and establish bus travel time prediction model for intersections with bus land and without bus lane. At the same time, the article also discusses the detectors location methods.The validation of the travel time prediction model is another important issue in this article. At first, we introduce the validation method based on fixed bus detector, and validating the precision of travel time prediction model based on that detection method. Then this article pay great attention on the validation based on GPS data, developing the bus dynamic control program and bus travel time prediction program by VB, and analyses the validation results in detail. Comparative results show that the precision of the model based on fixed detection and GPS does not have significant difference, but it is a trend that adopting GPS in the bus for dynamic management.At last, this article concludes the research results of this article and analysis the expectation of the coming research. All of the research is one part of bus signal priority system, the results can provide theory basis and technique support.