Traffic Coordination Control Theories And Methods Research Based On Group Dynamics

Effective design on coordination control of intersection&intersection, intersection&group of intersections, and group&group from an overall strategy view, is the newestdemand of urban traffic control systems, for achieving the objectives that traffic optimalrunning, dealing with insufficient urban traffic capacity, traffic congestion and pollution. Inthis paper, using theries of group dynamics to research on two intersetions coordinationcontrol, artery coordination control and coordination control at oversaturated conditions arethe core objectives. And the main work and achieves are summarized as follows:1. The basic model of traffic coordination control are discussed and summarized, and soas the methods for intersetion&intersection coordination control, intersetion&group ofintersections. After that, some essential issues are presented for the promising trafficcoordination control theory based on group dynamics. And finally, through the analysis ofthe characteristics of these issues, the basic method systems of the theory are presented.2. The conception of mimetic phase difference is presented. We analysed thecharacterestics of the arrival model and delay model of traffic flows, and confirmed thecontrol strategies set of each intersection in two intersection coordination control. Then themethod of group evolutionary game is introduced. Each situation will be investigated. Thebalance point (the best point) and its benifit in the situations are calculated, and so the beststrategy in the game is confirmed. On this basis, traffic coordination control model andmethod based on group dynamics are suggested, and so does the corresponding solvingalgorithm. This research will be the newest part in traffic coordination control theory, and italso increases the depth of application of group dynamics.3. In order to seek an effective method of traffic coordination control for road networks,the traffic behaviors at intersections are analyzed based on the macroscopic transmissionmodel via a gridding procedure, and a new macroscopic simulation model is constructed tofast evaluate control schemes. Then, by taking the optimal traffic running as the objective, abi-level programming model for traffic coordination control is proposed. Moreover, bycombining the macroscopic simulation model with the proposed bi-level model, a method oftraffic coordination control based on the improved macroscopic traffic model is presented. The method is finally tested on a virtual network with three different traffic demands, and theresults are compared with those of the Transyt-7F method. It is found that the proposedmethod is feasible and is superior to the Transyt-7F method especially in the high demandscenario.4. Artery coordination control strategy is designed for high traffic demand situations.With the method of hierarchical coordination, dynamically adjusting and optimizing cycleand green ratio of intersetions, the main flow on artery will be controlled under ideal phasedifference, and at the same time opposite flow under optimized offset coordination. Groupdynamics is adopted to establish adjusting operator for green ratio. Then the stability of theoperator is verified. The main ideal method of phase difference coordination to traffic floware discussed, and the linkage formula of cycle and offsets of neighbor-intersections areestablished, and so does the adjustment algorithm for the cycle of each intersection. Anotherinching green ratio algorithm is presented, for the congestion dilemma of opposite trafficflow. And based on these, the optimization model is established. The solving algorithm isgiven subsequently. Finally, the dynamic performance of the method is analyzed in detail.5. The coordination model and method for oversaturated network is presented, based ongroup evolutionary and the discussion in Chapter2. In this method, the key intersection(s) inthe network must be firstly identified, and so one or more intersection group(s) can beformed, which are all key-interseciton-centered. These groups can accurately control thetraffic volumes that come into the key area, and so to manage the demand of the key area orintersection. This will be a valid method for avoiding key area congestion. Thus the basicscheme for oversaturated network control is produced. And all to do is to optimize the otherparameters of intersections further. On this basis, the coordination control method isestablished. Some simulations are used to test this method, and the results show theeffectiveness of the model and the method. Finally, some important factors that will affectthe performance of the method are further discussed, and some conclusions are found, thatmaybe effective approaches to promote the performace of the method.