Research On Coordination Strategy Of Urban Traffic Control System And Urban Traffic Flow Guidance System

It is necessary and essential to cooperate Urban Traffic Control System with Urban Traffic Guidance System, which will integrate traffic facilities and thus building both intelligent and economical transportation system. The paper is supported by Doctor Science Research Foundation of China"study on theory and method for cooperation of urban mixed traffic control system and urban traffic flow guidance system"and ministry of education 973 pre-study Foundation"the theory, model and implement of urban traffic system intelligent coordination", mainly studied on cooperation strategy. As we all know, a good strategy can save cost, avoid resource waste, reduce the calculated and respond time. Also a good strategy creates conditions for respond traffic flow stations in time.The first chapter mainly introduced the significance and meaning of this paper. Start from the mechanism of Urban Traffic Control System (UTCS) and Urban Traffic Guidance System (UTFGS), analysis the relationship between UTCS and UTFGS in detail. UTCS and UTFGS connected with each other closely in space and time, they are input and restrict to each other, and they have the same management object and the same management target. Thus, to cooperate the two systems can solve the traffic problems more efficiency; then, the paper summarize the study history and product about cooperation from home to abroad, and point out the deficiency of them. Lastly, present the main content and chapter arrange of this paper.Chapter two summarized the cooperation content and the cooperation mode. From the functionary scope of cooperation, we summarize the cooperation content to be time and space cooperation, information cooperation, strategy cooperation, arithmetic cooperation, and technology cooperation in urban road. The paper only studies the cooperation strategy, because the cooperation strategy is the foundation to carry out cooperation. We found that the core problem of strategy cooperation is cooperation mode, there are six different kinds of cooperation modes, they are independence mode, emphasize control system or guidance system modes, harmonize mode, and integration mode. To each mode, we introduced their work principle, advantage and disadvantage. This is the bases for making cooperation strategy.Chapter three introduced the cooperation strategy in different traffic environments. A good strategy should change with traffic environments. This chapter just studies the cooperation strategy in different environments. Firstly, we divide the traffic condition to be four levels: smooth, slightly crowed, crowed and congestion. To each station we studied the cooperation strategy from the management cost, the calculated speed and the management effect, point out the cooperation goal, the cooperation mode and set up the cooperation arithmetic. In free conditions, in order to quicken the calculated speed, we choose independence mode; In slightly crowed conditions, the cooperation strategy play the important role in traffic management, if we cooperate the two system effectively, the traffic will avoid the crowed conditions, so the harmonize mode and integration mode will be good choice; If crowed conditions happened, emphasize guidance system mode is the best choice, guidance system can evacuate the traffic flow promptly. We define the congestion condition to be crowed of all the networks, in this conditions, all the traffic management have no effect, we should build more route to enlarge the network of the city.Chapter four studied the cooperation strategy in special management goal. A good strategy should consider not only traffic environments, but also management goal. Even to the same traffic environments; the cooperation strategy will be different if the management goal is different. We just study the cooperation strategy in special management goal-signal priority. There are two kinds of priority: the rescue car priority in emergency and the transit priority.Aimed at the limitation of present green signal control to rescue car, we divide the traffic flow in intersection to be two kinds, priority flow, and the lag flow. Then we design an absolutely priority strategy to rescue car. Before the rescue car reach the intersection, we control the priority flow to be green, and the lag flow to be red, this can make sure the rescue car to pass the inter section freely. At the same time, in order to relax the delay of social car caused by rescue car, we design a route guidance strategy based on absolutely priority of rescue car. This can reduce the respond time to incident and increase the capacity.Then the paper studied the cooperation strategy in transit signal priority, the bus is more than rescue car in urban road, so they can't get absolutely priority. So we design a hierarchical cooperation strategy between transit signal priority and social car route guidance, and set a model based on passenger and car. During the cooperation there are two layers, function layer and the cooperation layer. In function layer, we establish transit signal priority model and route guidance model separately in function layer, and to coordinate the two systems in cooperation layer. Until get the optimize result of control system and guidance system. This strategy can reduce the delay of social car caused by transit signal priority.Lastly, we set a network to simulate the cooperation strategy in transit signal priority. The network is based on changchun renmin street, nahu road , yatai street and free road, that's a cooperation zone. We design two projects, the first one has only transit signal priority, the second project cooperate the control system and guidance system. Analysis the result of the two projects, we found that in cooperation conditions, the traffic state is better than no cooperation condition; to cooperation the two systems can get distinct effect.Chapter five is a summary of the thesis as well as some aspects that need further research.