| 摘要 |
PROBLEM TO BE SOLVED: To provide an on-vehicle navigation device for searching a route up to the destination, even when the data of new and old versions are mixed, by updating of map data classified by administrative districts (for example, all prefectural and city governments), and to provide a route search method. SOLUTION: The on-vehicle navigation device comprises making the map data as a two-layer structure of an upper-layer level and a lower-layer level; updating by the prefectural and city governments in the upper-layer level; preparing updating version classified by all prefectures in the lower-layer level; referring to the map data, when setting the destination; searching the route up to a position in the neighborhood of the destination, by using the data of the upper-layer level when determining that the map data different in the version mix in an area, on the way to the destination; and searching the route up to the destination by using the data of the lower-layer level, when the data of the lower-layer level in the neighborhood of own vehicle position are the same version as that of the data of the lower-layer level in the neighborhood of the destination accompanying the movement of own vehicle. COPYRIGHT: (C)2008,JPO&INPIT |
