Intelligent Urban Transportation Information Platform And Dynamic Route Guidance System

The traffic congestion has increased steadily in urban traffic networks. Comparing with the expanded rate of roads and other infrastructures, vehicle ownership and the use of vehicles are growing much higher. Transportation authorities are increasingly turning to existing and new technologies to preserve traffic mobility, improve road safety, and minimize congestion, pollution, and environmental impact. The integration of computers, information, and communication technologies will change greatly the transportation in future. This exciting new field is now known as intelligent transportation systems (ITS).In this paper, we concentrate on some specific portions of ITS: GIS system based on digital map database, GPS system and map matching algorithm, traffic information system, land-based vehicle location and dynamic route guidance system, and shortest path algorithm.Our GIS system contains digitized map information with a predefined format. It can be processed by a computer for map-related functions, such as identifying and giving location, road classifications, traffic regulations, and travel information. GPS is used for automatic determination of the position of the vehicle or a mobile device. Because of the error of positioning, we presented a point-based map matching algorithm, it is a method of matching the position (or trajectory) measured or received by GPS module with a position on the map provided by the map database module. Through analyzing the real-time SCATS data with traffic flow theory, the vehicles real-time speeds in different road sections are obtained. On the congestion condition, we use the traffic emulation tools to compute the speeds of road sections. The real-time traffic infonnation obtained from SCATS data is used in traffic information release and vehicle navigation system. We discussed a complex system named dynamic route guidance system that navigates the vehicle automatically through the road network, assisted by real-time traffic infonnation. In this paper, the architectures and performances of a centrally determined route guidance system and a distributeddynamic route guidance system are studied and compared. Route planning is the process of helping vehicle drivers plan a route prior to or during their journey. It is based on a given map provided by the map database module, along with real-time traffic information received via a wireless communication network. Knowing the route, it may work with the GPS module and the map-matching module to guide the driver to follow a particular route to the destination. Based on the overview of the research and development of the shortest path algorithm, an effective algorithm, the improved dijkstra's algorithm implemented with double buckets and the heuristic A algorithm, is proposed. In this study, by using the real-time traffic information, the new shortest path algorithm is analyzed and verified, and the performance of vehicle navigation is improved.