Research On Intelligent Control Strategy And Simulation System For Urban Traffic

In China,as the number of cars increase ceaselessly, the city traffic problem become more and more serious. It is imperative that advanced scientific and technology is applied to solve the management problem of urban traffic. Intelligent Transportation System(ITS) is integrated with the latest technology achievements, such as the information,communications ,computers, electronic control, global positioning system and geographic information system, which can be applied in the transportation management system. Urban transport system is a huge system with randomness, complexity and uncertainty. Currently, path planning of existing urban intelligent transportation system is based on static road information and simple constraint network model, in which real-time status information and running efficiency of vehicles are not taken into account adequately , so it is difficult to be used in practice effectively.In the paper, sections and intersections of urban road network being taken as research object, with travel time as the objective function, the travel time is divided into travel time of sections and delay time of intersection. Based on the traditional static network model, the parameter of link travel time is introduced. The status of traffic network is considered comprehensively, so the established dynamic network model can reflect the conditions of urban traffic in real time. Based on the Greenberg theory, the change state of parameter in the transport network is described, the intersection, lane width, design speed and other factors, took into account and the link travel time model is established. On the basis of the Webster model, other factors such as the traffic flow directions at intersections etc. are introduced, and then the intersection delay time model is established. The link travel time model and intersection delay time model are used to calculate the travel time of vehicles so as to make the calculation results fit the real state of urban traffic. Based on the characteristics of dynamic traffic network model, principles and features of existing algorithm of path planning are analyzed and compared. Improved Floyd algorithm is proposed based on dynamic programming and compact cycle structure. It has higher implementation efficiency for dense graphBased on the platform of Microsoft NET, development language tools C # is used with the component MapXtreme2008 of geographic information system development of MapInfo introduced, the system simulation software is established. The proposed model and method are studied by the simulation software .The experimental results show that the proposed network model and dynamic path planning algorithm is efficient for intelligent city traffic management.