Modeling And Simulation Of Microscopic Traffic Flow On Typical Roads In Vehicle-infrastructure Cooperation Environment

With the deep integration of smart roadside units and automobiles,the road traffic environment has gradually changed from static and unmeasurable traditional traffic environment to dynamic and controllable vehicle-infrastructure cooperation environment.How to reveal the coupling mechanism and complex operation rules among various traffic elements in the vehicle-infrastructure cooperation transportation environment is a scientific problem to be solved.Micro-traffic flow model uses microvariables to describe the relationship between vehicles and their movement characteristics,so as to reflect the evolution law of traffic flow.Therefore,the research on micro-traffic flow model in the vehicle-infrastructure cooperation environment has become a hot spot in the field of Intelligent Transportation.In order to accurately depict the micro-behavior of vehicles and reveal the evolution law of traffic flow in the vehicle-infrastructure cooperation environment,this paper mainly studied the micromodel of traffic flow around three typical road scenarios: ramp,curved rod and signalized intersection in the vehicle-infrastructure cooperation environment,and then explored the influence of factors such as front vehicle weight coefficient,road slope,curvature radius,and traffic lights on the traffic flow.The main research contents included:(1)The vehicle-infrastructure cooperation system and its key technologies were elaborated,and combining the three dimensions of vehicle automation,road infrastructure intelligence and network interconnection,the main technical features of today’s vehicle-infrastructure cooperation system were clearly pointed out,which lays an environmental foundation for follow-up research of this paper.Furthermore,based on the NIGSIM dataset,the mechanism of Vehicle-to-Vehicle communication on vehicle micro-behavior was analyzed by gray correlation method.(2)In view of the problem that the existing micro traffic flow models fail to take into account the comprehensive influence of road slope and multi-front vehicle information,which leads to the inaccurate description of car-following behavior on the ramp in the vehicle-infrastructure cooperation environment.So,based on the Full Velocity Difference model,an intelligent network car-following model considering road slope and dual-front vehicle information in the vehicle-infrastructure cooperation environment was proposed,and the linear stability of the model was analyzed using the perturbation method.The numerical simulation results were in agreement with the theoretical analysis,which showed that the improved model can accurately describe the car-following behavior on ramp in the vehicle-infrastructure cooperation environment.At the same time,the study also showed that the stability of traffic flow increases with the increase of slope on uphill,decreases with the increase of slope on downhill,and increases with the increase of the front vehicle weight coefficient.(3)In view of the problem that the existing micro traffic flow models fail to take into account both the curvature radius of the road and the comprehensive influence of the front vehicle information,which leads to the inaccurate description of the carfollowing behavior on curved road in the vehicle-infrastructure cooperation environment.So,based on the traditional Intelligent Driver Model,an intelligent driver model for curves with dual-front vehicle information in the vehicle-infrastructure cooperation environment was proposed,and the linear stability analysis of the model was carried out using the perturbation method.The numerical simulation results were in agreement with the theoretical analysis,which showed that the improved model can accurately describe the car-following behavior on curved roads in the vehicleinfrastructure cooperation environment.At the same time,the study also showed that the stability of traffic flow on curved roads increases with the increase of curvature radius of roads and weight coefficient of front vehicles.(4)In view of the problem that the existing micro traffic flow models fail to consider the influence of signalized intersections on vehicle operation,which leads to inaccurate description of car-following behavior at signalized intersections in the vehicle-infrastructure cooperation environment.So,this paper analyzed the guiding strategies adopted by vehicles at signalized intersections in the vehicle-infrastructure cooperation environment,and proposed a car-following model considering signaled intersections under the conditions of different guiding strategies.The numerical simulation results showed that the proposed model can well describe the car-following behavior at signalized intersections in the vehicle-infrastructure cooperation environment.At the same time,the study also showed that the traffic efficiency of vehicles at signalized intersections were significantly improved in the vehicleinfrastructure cooperation environment.And with the increase of the length of the guidance zone at signalized intersections,the higher the traffic efficiency,the lower the fuel consumption and the emission of exhaust pollutants.In summary,this study conducted modeling and simulation research on the microscopic traffic flow at slopes,curves,and signalized intersections in the vehicleinfrastructure cooperation environment.The constructed model can accurately depict the microscopic behavior of vehicles in the vehicle-infrastructure cooperation environment and effectively reveal the evolution rules of traffic flow.