Research And Simulation Of Ramp Merging Algorithm Based On Cooperative Vehicle Infrastructure

According to statistics,about 30% of the traffic accidents in China occur in the ramp area every year,and the main incentive is the traffic disturbance caused by remittance vehicles in the ramp confluence area.More and more attention has been paid to traffic control in the confluence and diversion roads.Based on the vehicle networking technology,this paper studies the collaborative confluence algorithm of vehicles in the confluence zone of the ramp.And it proposes a coordinated control method based on the speed adjustment in free-time period through the analysis of the cooperative regulation mechanism,and carries out simulation analysis of the algorithm.The main work of the thesis is as follows:Firstly,the paper proposes a framework of confluence algorithm based on the analysis of the research status of domestic and foreign research,vehicle-road coordination technology and the demand of road confluence algorithm.In order to ensure the real-time performance of the algorithm,a communication strategy between the decision module and the execution module is designed.Therefore the communication efficiency is effectively improved.Secondly,the decision module and execution module of the main components of the algorithm are designed in detail.A time planning model is proposed in the decision module.This model integrates the principles of virtual queues and kinematic principles,and uses free-time period to adjust the time conflicts and spatial conflicts of traffic flow to improve traffic efficiency.In the execution module design,several conditions of speed control were analyzed,and different modes of control algorithms were designed according to different situations,and then a suitable amount of optimization was performed to ensure the comfort requirements.Finally,Veins car networking simulation system was selected to simulate the algorithm in the paper.Combining the division of the algorithm module and the characteristics of the Veins simulation system,the on-ramp merge control system is designed and coded,and the simulation results are collated and analyzed.The simulation results show that under natural driving conditions,traffic conflicts in the converging area of the ramp was caused by lacking of interaction of two lane vehicles.When the density of the two lanes is over saturated,the traffic congestion becomes shorter with the increase of vehicle density.When this algorithm is used to control the confluence process,traffic conflicts in the confluence area are reduced,traffic efficiency and safety are improved to a certain extent,and the traffic congestion can be delayed when the vehicle density is over saturated.