Research On Space-time Cooperative Method Of Urban Intersections In Intelligence Network Connection Environment

With the continuous growth of vehicle ownership,the traffic demand and pressure of traffic management are increasing day by day,which puts forward the new requirements for intelligent traffic control system.Compared with the optimization strategy of the traditional environment,the time and space resource allocation of the intersection in the intelligent network environment is more intelligent,more flexible and more efficient,which greatly improves the traffic operation efficiency of the intersection.Firstly,based on the existing domestic and abroad research on the speed guidance strategy and optimization of time and space resources in intersections,the literature review is conducted,which introduces the related theoretical technology and the present status of development in the intelligent networked environment,and also explores the impact of the penetration rate of networked cars on the capacity of road traffic in the networked and non-networked cars mixed environment through the simulation experiments.The result shows that the capacity of road traffic is improved with the increase of the penetration rate of networked vehicles.And compared with the traditional driving environment,when the penetration rate of networked vehicles reaches at100%,in the signal cycle of 60 s,80s,100 s,and 120 s,the capacity in the intelligent networked environment is increased by 62.32%,58.79%,62.04% and 56.50%,respectively.Besides,this paper divides the interval of penetration rate into low interval（0%～30%）and high interval（70%～100%）based on the analysis of the results of operating state indicators.Secondly,according to the speed guidance control method of isolated signalized intersection,this paper builds a speed guidance control model of isolated intersection and evaluates it through the PTV Vissim simulation software.The simulation result illustrates that compared to the nonspeed guidance control method in the traditional environment,the average delay of vehicles at intersections is reduced by 88.16% and the fuel consumption is reduced by 65.6% approximately.Furthermore,the method of predicting the queue length of the entrance lane is added to the vehicle speed guidance model.The result presents that the indexes are further optimized compared to the method without the queuing prediction.Additionally,based on the speed guidance control and queuing prediction of isolated intersection,this paper establishes the speed guidance control model in the continuous intersections under networked environment,and studies the changing trend of vehicles passing through continuous intersection in the form of coordinated fleet under different penetration rates of intelligent networked vehicles.Taking three consecutive signal-controlled intersections as an example,the simulation result shows that compared with the non-vehicle speed guidance control method in the traditional driving environment,after the implementation of speed guidance control and queue length prediction in the fully networked environment,the proportion of vehicles passing through three consecutive intersections without stopping is increased by 68.6%.Finally,this paper proposes the space resource allocation method according to the unbalanced characteristics of entry steering.Also,the signal control optimization model is established based on actuated control under fully intelligent networked environment.Furthermore,this paper analyses the signal cycle calculation method and constraint conditions under different degrees of saturation in the networked and non-networked mixed environment,classifies the signal phase green time allocation method,and establishes a multi-objective signal control optimization model for the signal control strategy of medium-high degree of saturation for intersection.Taking the intersection of Xinjinci Road and Changfeng West Street in Taiyuan as an example,PTV Vissim simulation software is used to simulate the time resource optimization,space resource optimization and collaborative optimization of space-time resources.The simulation result shows that compared with the traditional driving environment,the vehicle delay at the intersection which in the fully connected environment is reduced by 73.3%,the number of stops is decreased by 52.6%,the average travel speed is increased by 20.26%,and the traffic operation status of intersections has been significantly improved.