Research On And Implementation Of Intelligent Inquiry And Optimal Path Planning On VNS

Both intelligent inquiry and optimal path planning are important research subjects and key technologies for ITS. To solve problems of miscellaneous conditions, inefficiency and little intelligence in the information inquiry of VNS and to meet users'needs, it is necessary to improve the flexibility, efficiency and intelligence of the inquiry. Firstly, techniques of the blocks of maps, the unfixed-length data structure and the double index have been applied to embedded devices with limited and low speed memories. Secondly, a new inquiry system, which has fuzzy optional inquiry modes of Chinese characters, digits and the first letter of Pinyin, has been designed based on algorithm of Hash-Mapping. Finally, an intelligent inquiry system has been built up successfully by adding category and region setups to the index structure of Hash-Mapping.Optimal path planning in this paper is expected to solve two problems: how to build the topology of roads automatically in the digital map and how to realize the optimal path planning in the VNS. Firstly, data structures of road topology network have been built and an algorithm for building the topology of the network automatically has been designed. Secondly, the realization and application of algorithms of Dijkstra and A* in optimal path planning of VNS have been discussed. Finally, an optimal path planning is realized by the algorithm of A* based on researches above.More over, the intelligent inquiry and the optimal path planning have been developed successfully in the cell phone platform of MTK and integrated into the complete vehicle navigation software with other modules of VNS.