Research On The Optimal Path Planning In Vehicle Navigation System

Vehicle navigation system is an important part of intelligent transportation system, which is a driver assistance system by comprehensively applied Vehicle positioning system, geographical information technology, computer technology, network technology and modern communication technology. It is effective to prevent traffic blockage, decrease traffic accidents and reduce vehicle delaying time in the road.A basic function of vehicle navigation system is path planning, which helps a driver find an optimal path from departure place to destination. In order to prove the path planning algorithm's practicality and technical feasibility, the thesis put forward a calculation model of road section weight value, which is different from previous weight value models. As the effect of intersection queue length is taken into account, it makes estimation of traveling time more accurate.Actual vehicle navigation system has a high demand of path planning solution's rapidity and a low demand of its optimality. Based on characteristics of road network, the thesis proposes a rapid path planning algorithm by using bidirectional search, projection method and binary tree theory. Comparing with the experimental analysis of Dijkstra algorithm, the algorithm has smaller searching space and faster searching speed, so it is more suitable for vehicle navigation system.At last, it is given the development scheme of vehicle navigation system prototype, including vehicle equipment which can be installed in bus, cars and other related motor vehicle and communication receiving software of data center terminal. It is also given realization process of muti-threading programming technique, GPS data processing and serial port communication technology base on Windows CE operating system.