Cooperative Control Of Traffic Signal And Connected Vehicles At Intersections In The Mixed Traffic Environment

Intersection is commonly seen in urban scenario,and it has significant influence on traffic efficiency and vehicles' fuel consumption.Vehicles' frequent stop-and-go and idling behavior make fuel consumption worse,which is inevitable in traditional constant phase time traffic control method when traffic jam happens.The development of Intelligent and Connected Vehicle(ICV)gives more opportunity to further optimize the traffic condition.On one hand,ICVs can acquire traffic environment infomation like traffic light phasing to optimize their driving strategy.On the other hand,ICVs can aquire other vehicles' information,so controlling of the ego vehicle can have benefits on the following vehicles.However,it may take decades to realize the fully popularization of ICVs,so research on mixed traffic environment is of great importance,which is not fully studied by related researchers.In this study,the behavior of Human-Driven Vehicle(HDV)is considered in the optimization.In mixed traffic scenario,an ICV platoon formation method and a hierarchical optimized traffic light controller are proposed,which can improve both traffic efficiency and fuel economy under different market penetration rates.To take HDV information into consideration,this study proposed a mixed platoon formation method.By combining 1 ICV and N HDVs into a standard "1+N" platoon,the ICV has the initiative to guide the following HDVs in approaching the intersection.Based on system analysis,platoon stablity and controllability are discussed.System stabilization analysis is used in calculating the theoretical stabilization time of the system.More research is done on drivers' driving behavior.The optimal car following distance and maximum vehicle passing amount are discussed under constant phasing scenario.Focused on the intersection approaching in constant phase traffic light,a mixed platoon optimal control model is proposed and the pseudo-spectral method is used in solving the optimal control problem.Fuel consumption is optimized in this part.A HDV can only pass an intersection under the traffic lights' regulation,so based on the mixed traffic model mentioned above,reservation-based traffic light control method is designed.A first-come-first-serve(FCFS)method is widely used in single ICV priority assignment,which is expanded to the mixed traffic environment.A poriority assign method is designed considering the size of mixed platoons,in which eight-phase traffic light phase assignment is realized.Traffic efficiency can be optimized in this part.Based on the micro traffic flow model,a simulation platform is built to verify the optimization performance of the proposed algorithm.