Optimization And Realization Of Green Channel For Specially Authorized Vehicles

With the accelerating process of urbanization,the internal structure of urban road network is also more complex.A series of emergencies in the road network crisis the safety of people’s lives and property to a great extent.When an unpredictable emergency occurs,the city emergency center will send special authorized vehicles to the place where the accident occurs to carry out rescue work.The shorter the vehicle arrival time is,the smaller the loss caused by the emergency will be.Although the special authorized vehicles have the priority of road traffic,they are also affected by vehicle congestion in the actual driving process,and it is difficult to achieve the priority of traffic,resulting in great delay.Therefore,on the premise of reducing the impact on ordinary vehicles,this paper focuses on how to make special authorized vehicles quickly arrive at the place where the accident happened.Firstly,a special authorized vehicle routing scheme based on discrete particle swarm optimization(DPSO)is proposed.Considering the traffic state parameters of each road section in the road network,the weight of each road section is calculated,and the optimal path selection model is established on the road network connected graph abstracted by graph theory.Discrete particle swarm optimization(DPSO)algorithm is used to discretize the particle optimization process,and the optimal path is solved with the objective of minimizing the vehicle arrival time.Finally,the shortest time-consuming preset driving route is planned.Secondly,on the basis of the optimal path selected by the route selection scheme,a special authorized vehicle early warning system is proposed.The system combines the basic characteristics of VANET and urban road network to design a dynamic transmission scheme of emergency messages sent by special authorized vehicles,which mainly includes the dynamic transmission range of emergency messages and the forwarding rules of the receiving nodes.Then,it defines the avoidance strategies that other vehicles need to take in case of emergency,so as to reduce the situation that special authorized vehicles are interfered by other vehicles in the process of driving on the optimal path,so that special authorized vehicles can arrive at the accident site with less average travel time.Finally,in the part of experimental analysis,through the simulation of road network and simulation experiments,it is proved that the optimal path selection scheme and vehicle early warning system are feasible,which can effectively reduce the average travel time of vehicles on the optimal path in the process of special authorized vehicles.At the end of this paper,the shortcomings of the research work and the follow-up research content are described.