The Research Of Traffic Control And Guidance Collaboration In Area Boundary

The two keys to solve the problem of urban traffic are Urban Traffic Control and Urban Traffic Flow Guidance. Urban Traffic Control is an effective method of microscopic control for traffic flow. By analyzing each intersection’s arrival rate and traffic data of queue, Urban Traffic Control reasonably allocates green time for different phases in time dimension to control traffic flow towards downstream section in premise of meeting all phases’need. While according to real-time traffic conditions and rational guidance and distribution of traffic flow, Urban Traffic Flow Guidance provides pedestrians different congestion information and recommended path information to avoid congestion section and traffic accident section in area dimension.Area boundary belongs to the connecting portion of two different properties sub-regions, and is restricted to different methods of control and management often forming a traffic bottleneck. Traffic control and guidance collaboration in area boundary means integrate the dispersive role of traffic control and guidance in boundary ranges of neighboring control sub-district, and accomplish traffic flow management target of control sub-district by regulating control parameters (cycle and split) and guidance parameters (arrival rate) of signal control and guidance cooperate with each other. The collaboration target is to use the Collaborative method of signal control and guidance for producing better results than sum of them.This paper is constructed by three parts as follows:(1) Division of control sub-district considering area boundary. The division provides implementation basis for collaboration in area dimension, that is it determines where to implement by analyzing partition principle of network. This paper proposes how to partition collaborative sub-district based on intersection relative degree. After knowing key intersection, it determines whether the intersection is in the same sub-district with the key one by calculating relative degree between intersections, finally it determines partition results by comparing sub-district’s delay, queuing and travel time of different methods.(2) Judgement of cooperation opportunity can provide some basis for activation time of cooperation by predicting the traffic state in the subarea. This paper has analyzed the variation of the traffic parameters when traffic is congested, reduced the dimensionality of link information through PCA (principal component analysis) method, and proposed a cooperation opportunity anticipation algorithm based on prediction data combined with fuzzy synthetic evaluation method. Simulation result shows that this algorithm can effectively anticipate the traffic state of next time interval (time interval in this paper is set to be5minute), give a timely hint to the formation and dissipation of the traffic congestion. Then, analyzing the impact of vehicle arrival rate on the dissipation of traffic congestion can help search for the optimal opportunity to activate the coorperation strategy, and provide the basis for cooperation strategy and activation of optimization algorithm.(3) Area boundary traffic control and guidance collaborative optimization model. From the perspective of the system optimization, taking the comprehensive minimum of the total network travel time and intersection delay as target, it builds control and guidance collaborative model with the components of cycle, green ratio and inflow rate. This paper uses genetic algorithms to solve the collaborative model, distributes network traffic flow both on the time and the space, finally achieves the collaboration between traffic control and guidance. It takes the optimal solution results as the network input, and verifies with simulation through the software-Paramics, then the results show that this algorithm can effectively reduce the total network travel time and intersection delay and improve the operation efficiency.