Modeling And Simulation For Drivers' Route Choice Behavior Under The Impact Of VMS

With the rapid development of intelligent transportation technology at home and abroad, variable message signs(VMS) are applied widely in Transportation Information Real-time Publishing field, for its convenience, immediacy, and well implementing effect. VMS provide transportation prompt, warning or guidance information to traveler by way of graphic or letter signs. VMS can not only increase the travelers'especially the drivers' travel efficiency and security, but also help transportation managers to ease traffic congestion, improve road network overall efficiency and service level. However, the travel guidance information provided by VMS to improve the transportation efficiency is not always effective. The effect of VMS affected by many outside factors, and can not reach the expectations of traffic management, the rate drivers obey is often performance too high or too low. Therefore, the study of drivers'route choice behavior under the impact of VMS has important practical significance.The thesis analyzes the study in domestic and overseas on the first, and then analysis of the factors that affect the drivers' route choice behavior. The factors mainly including three aspects:real-time traffic information types (qualitative information, quantitative information, etc.) provided by VMS, personal characteristics of drivers (gender, age, driving experience, familiarity with the road network, etc.), road environment property (the congestion degree of the original path, the alternative path length and travel time, etc.). On that basis, this thesis carrying on the SP questionnaire survey of driver route choice under VMS information. The questionnaire considers the factors affecting driver route choice, surveys the drivers'route choice behavior in the case of qualitative information and three different levels of quantitative information with two possible paths. Then, according to the survey results, establishes the BP neural network model of drivers' route choice behavior under the influence of the VMS information. And on that basis establishes the drivers'route choice behavior Agent simulation model. The transportation system is abstracted to the multi-agent system that consisted of Driver-Vehicle Agent, Road Agent and the VMS Agent, the model including the control layer and the operation layer. The control layer realizes the route choice behavior of driver-vehicle Agent in real-time traffic information. The operation layer realizes the driver-vehicle Agent running on the road. At last, this thesis carry out the simulation experiments in Netlogo, analysis the effect of the overall road network operating efficiency under different VMS information, and propose the implementation advice of VMS.The simulation results show that VMS route guidance information can improve the overall road network operating efficiency in most cases. And the overall road network operating efficiency improved obviously with the rate drivers obey VMS information increase. However, the overall road network operating efficiency may reduce because excessive drivers change to alternate path will cause alternate path occurs congestion when the rate drivers obey VMS information is too high. Therefore, we should fully research the drivers'path change proportion and information publishing strategy of the current path and alternative path at different traffic conditions before setting VMS. VMS can publish route guidance information depending on different traffic volume and congestion of the current path and alternative path when the current path occurs congestion. This would ensure the VMS adaptive publish traffic information according to the different state of road environment, so that improve the road network's overall operating efficiency.