| In the on-ramp merging area of the highway,there is a potential conflict between the vehicles on the ramp and the vehicles on the main road.Vehicles on the ramp enter the main road,which may cause the vehicles to slow down or even stop,which not only affects safety and traffic efficiency but also increases energy consumption and environmental pollution.The rapid development of Internet of Vehicles,edge computing and connected and automated vehicles(CAVs)provide technical conditions for solving the above problems.With the help of the Internet of Vehicles and edge computing,the roadside infrastructure can interact with CAVs dynamically and in real-time within a certain range.The roadside infrastructure can obtain detailed information such as the position,speed,acceleration of each vehicle,real-time road conditions,etc.,and send instructions to the vehicles to make the vehicles drive cooperatively,which provides an opportunity for safe and efficient on-ramp merging.In this paper,we study the problem of on-ramp merging under the Internet of Vehicles.To achieve safe and efficient vehicle merging on the ramp,we propose the sequence optimization and platoon planning method.The specific research contents are as follows:(1)Based on the vehicle-road collaboration framework,a centralized hierarchical control architecture is proposed,and the system control process is designed.According to the characteristics of the on-ramp merging,on the basis of the centralized hierarchical control system architecture,the control system is divided into the edge computing layer and the vehicle system layer to balance the calculation pressure of each part of the system.The hierarchical system control flow is designed,and the vehicles is optimized wheel by wheel based on an event-driven strategy.(2)Considering the balance between real-time performance and optimization of the method,we propose a graph-based method to optimize merging sequence,and consider the influence of the merging sequence on the trajectory in the graph model,to reduce the total energy consumption,and at the same time Ensuring the efficiency of on-ramp traffic.First,the vehicles are grouped based on the hierarchical clustering method,and then the graph model is established to make the paths correspond to the confluence sequences.According to the optimization objective,the weight of the directed edge of the graph model is defined,and the shortest path is obtained in the graph model to optimize the merging sequence of vehicles.(3)Compared with vehicles traveling alone,vehicle formation on the highway has the advantages of safety,energy saving and high efficiency.When a vehicle enters a high speed,it is one of the opportunities for vehicle platoon In this paper,in the scene of the highway onramp,based on the motion planning of the vehicle,the vehicle forms a vehicle formation after passing through the merging point.Firstly,the terminal conditions of the merging point are analyzed,then the vehicle spacing of the platoon is adjusted based on the shortest time strategy,and finally the vehicle trajectory is optimized based on the optimal control principle to reduce vehicle energy consumption.The value principle derives an analytical solution to the vehicle trajectory.(4)Finally,we use MATLAB and the micro-traffic simulation tool SUMO to build a simulation platform for on-ramp merging.The simulation results show the effectiveness of the proposed sequence optimization and platoon planning methods in reducing fuel consumption and improving the efficiency of traffic,and the method has the potential for real-time applications. |
