The Present Situation of Vehicle Navigation Techniques in China and the Multi-Topological Formation and Route Computing of National Navigation Map

In China, the research of practical navigators is still in its initial stage and more difficult than in other countries with the large area and the complexity of its routes. At present, only several navigators are practical including the vehicle TV voice navigation system designed by us according to the concrete situation of road net in China. Based on GPS vehicle navigation, the topology forming and route analysis of a metropolis with very dense and complex roads are discussed. Under the special embedded circumstances, it must adopt patch method and classification to implement dynamic real time route analysis and topology forming. The patch method can resolve the issue of kinematic allocation, and the classification can reduce and speed up the operations. At the same time, a special process is put forward to compute the route when the vehicle deviates from the route. An ideal effect is realized on the finished navigator.