Research On Traffic Signal Coordinated Control Algorithm Of Saturated Trunk

With the acceleration of the process of urbanization and the increasing ownership of vehicles, the issue of transportation has become a hot thorny and difficult problem in urban. As the city traffic artery of traffic network, urban bone road take the great role in the traffic flow. To solve the urban traffic problem, the most importance is to improve the capacity of the skeleton route, to reduce the number of vehicles blocking. Owing to geography resources and the funds limit, to satisfy the needs of municipal transportation is hard to implementation just by big investing in traffic construction still. Therefore, improving the capacity of delivery vehicles about the existing traffic line become the breakthrough point of solves overburdened of the urban road facility.At present, the hot spot is intelligent dynamical control method which can make the traffic control plan according to the traffic flow changing in the traffic control field. However, the traffic flowing usually is in the saturated or close saturated condition on the skeleton route in the urban traffic network. In this case, there are many vehicles waiting at every direction of the crossing. So, due to the intelligent dynamical control method losing the factors used to making deciding, it degenerates to the static random phase-offset signal control.On the basis of analyzing problems of the skeleton route in the urban traffic network, the thesis designs new algorithms of traffic signal coordinated control. The research mainly includes several parts as follow:Firstly, in view of the non-special distance between intersections, the thesis designs coordination of timing algorithm, "Best Arrange", which forms the largest bidirectional green-band, according to saturated skeleton route status. Using "Best Arrange" algorithm , the vehicles can plus-formed cross all intersections without any blocking by the red signal at legal high speed ,also make sure the sub-route at the normal scheduling plan. Thus, it greatly reduces the number of starting and parking vehicles, and improves the throughput capability of the trunk road.Secondly, with the increasing of intersection on the bone line, the probability is reduced to find a suitable strategy of signal control, which can form the largest bidirectional green-brand on the bone line. At this point, the thesis designs "Greedy_BoneLine_Arrange" algorithm. This algorithm cuts off the bone line to several partitions, and makes sure the number of partitions is the smallest by greedy thinking, every partition can be used by "BestArrange" is the premise. In view of the different saturation between each signal light, the thesis designs "Saturation_BoneLine_Arrange". This algorithm can minimized the total delay time by dynamic programming thinking. Using this algorithm, the total delay time of generated by stop signal will be minimized in whole bone line.Finally, the thesis makes a conclusion and proposes the future research directions.