In-vehicle navigator

Abstract

Abstract PURPOSE:To shorten a route calculation time by allowing the 1st route calculating means to retrieve a connection node between upper and lower hierarchical layers from a road net data including a current position and allowing the 2nd route calculating means to retrieve a connection node between upper and lower hierarchical layers including a destination to calculate respective routes. CONSTITUTION:The route is calculated by a 1st route calculating means D1 to guide a driver from the current position up to a node included in the prescribed range W2 of the destination and then the detailed route up to the destination is calculated by a 2nd route calculating means D2 to guide the driver up to the destination. Since the calculation of detained routes around an extremely far destination e.g. can be postponed, the whole calculation time can be shortened as compared with a case for calculating detailed routes around the destination from the initial stage, and when conditions on the way of traveling are changed, it is unnecessary to recalculate the route.

Inventors

• 👤 Takeo Ikeda
• 👤 武夫 池田
• 👤 Kenji Amame
• 👤 健二 天目
• 👤 Kunihiko Mitsufuji
• 👤 三藤　邦彦

Bibliographic Details