Cooperative Merging Control For Multiple Connected And Automated Vehicles At Highway On-ramps

Cooperative merging of connected and automated vehicle(CAV)at the highway on-ramps is the research focus.Considering the traffic congestion,energy consumption,environmental pollution and security risks in this scenario,we conclude the work of this paper in four aspects.First of all,the trajectory planning of CAV’ cooperative merging was optimized;Secondly,we optimized the merging sequence of all vehicles when new CAV entered the control zone;Thirdly,after the optimization of merging sequence,we implement longitudinal platoon control for groups of vehicles within a predetermined distance;Finally,the team built the CAV model experiment platform and carried out relevant experiments.Numerical simulation and experimental results prove the validity of the work in this paper.Firstly,we formulated the problem of cooperative merging at highway on-ramps,then followed the geometric configuration of constant distance,optimizing the trajectory of the CAV.Afrer that,the optimal trajectory planning problem was transformed into the bolza problem with terminal moment freedom and terminal state constraint.We solved and obtain the cooperative optimal control law of each vehicle.Secondly,based on the method of trajectory planning,in order to coordinate the optimization of energy consumption and traffic efficiency before merging,a joint cost function was established as the benchmark of adjustment rules.The merging sequence was adjusted and optimized through cooperative game theory when new CAV entered the control area,so as to optimize the sequence of vehicle groups in real time.Then,different vehicle groups were formed on the main road and secondary road after optimizing the vehicle sequence.When adjacent vehicles were too close to each other,each vehicle group can be regarded as a homogeneous platoon,then we used a distributed linear feedback controller to realize formation control.In the final,the stability control area under the PLF communication topology was obtained analytically,which can not only guarantee the internal stability of the platoon,but also guarantee the string stability,ensuring the safety of all CAV when they effectively pass through the merging area.Finally,due to the requirement of CAV’ cooperation and the need of algorithm research and verification,the micro-platform was built.The design of the platform involves three aspects:chassis design,hardware design and software design.It has realized the functions of highprecision positioning,environment perception,path planning and the following control between two vehicles.The platform can implement more cooperative algorithm in the future.