Cooperative Merging Control Strategy Of Connected And Automated Vehicle Accounting For Platooning

The highway merging area is a typical traffic bottleneck section,which is easy to induce traffic congestion and accidents.The emergence of connected and automated vehicle and vehicle-road coordination provides a new solution for alleviating traffic congestion and accidents in the merging area.In particular,the platooning control technology of connected and automated vehicle has attracted great attention from the industry because of its ability to reduce the headway between the vehicles,improve the road traffic capacity,and reduce the energy consumption of vehicles.Therefore,focusing on the design of the cooperative merging strategy of connected and automated vehicles,this paper carries out the research of CAV platoon model based on driving data,the sequence planning of platooning CAV merging based on game,the analysis of CAV lane change merging spacing,and the planning research of lane change merging trajectory,and takes some sections of G25 highway as examples for simulation verification.The thesis research has important guiding significance for improving the traffic safety and efficiency of highway merging areas and reducing vehicle energy consumption.Firstly,for the problem that the spacing setting of the existing platooning model is too conservative or radical,the recommended setting scheme of vehicle platoon spacing based on the driver’s real vehicle experiment is studied.Through the following and lane changing experiments of 10 drivers in Huzhou,more than 30,000 driving behaviors and surrounding vehicle relative motion data and 10 G experimental videos of each driver were obtained.Based on the video characteristics,driving behavior characteristics and relative motion characteristics of the surrounding vehicle,the collected sample fragments of following,changing lanes and high-speed driving were screened.Then,according to the driver’s following distance and following speed distribution,the driver’s driving style and the distribution of the following and changing distances were extracted.Finally,according to the distribution of the headway of the conservative and aggressive drivers to change lanes,the recommended setting of the platoon headway is given.The simulation results show that the conservative headway is used as the inter-platoon distance of the platoon,and the aggressive headway and the minimum critical headway of lane change are used as the intra-platoon headway of the platoon,which can effectively ensure the integrity and safety of the platoon and improve the road traffic capacity.Compared with virtual mapping,the collaborative game strategy improves the average speed,energy consumption,and travel time about 15-18%.Secondly,for the problem of high merging conflict and low merging efficiency of non-platooning vehicles,a global optimal merging sequence control strategy based on collaborative game is proposed.The multi-platoon game problem is decomposed into multiple two-by-two platoon game problems,and the optimization goal is to take the lowest energy consumption,highest efficiency and best safety performance of the vehicle as the optimization goal and optimize the merging order and acceleration trajectory with the speed,acceleration limit and safety distance as constraints.This strategy outperforms the FIFO control strategy,resulting in an increase in average speed about 15%,25% reduction in the number of stops,and 20% reduction in fuel consumption.Thirdly,the existing lane changing and merging research are mostly focus on single vehicle,which cannot be applied on lane changing and merging with different size,so a collaborative lane changing decision and a trajectory planning method are developed for vehicle platoon.Four typical scenarios for changing lanes for platooning vehicles were discussed.Considering platoon to establish safety constraints for dynamic disks extends the existing five-degree polynomial lane change model.Analyzing the fuel consumption,HC and CO2 indexes of the platoon under different flow rates,as well as the number of vehicles changing lanes under different platoon lengths,the results show that with the increase of vehicle flow,the platoon lane change rate increases,and when the traffic reaches saturation,the lane change rate is the lowest.Finally,taking the merging area of the Changshen highway section as an example,the simulation system based on SUMO is tested and analyzed,the entry and exit traffic data of each toll station were collected separately,and the distribution of average speed,number of stops and fuel consumption indicators under three different strategies was analyzed under different traffic scenarios.The applicability and effectiveness of the platoon connected and automated vehicles collaborative merging strategy are verified.