| 摘要 |
PURPOSE:To shorten the wait time up to the completion of a search for an optimum course by using an intersection network list. CONSTITUTION:An optimum course search part 15g generates the intersection network list from road data on a CD-ROM 11 as to a map of the periphery of the position of a vehicle sequentially during a travel of the vehicle in normal guide mode, and updates and stores it in a course search memory 15h and when a route is searched for at a driver's request, an additional intersection network list is generated from the road data and additionally stored if the intersection network list stored in the course search memory 15h is deficient as to an area including the part from the starting point to the destination. Then the optimum course connecting the starting point and destination is found by Dijkstra method by using the intersection network list stored in the course search memory 15h and the found optimum course data are stored in a guide course storage part 15i. |
