| 摘要 |
PROBLEM TO BE SOLVED: To obtain a navigation system for vehicle in which a user can search a course with no anxiety by determining a returning course corresponding to a currently traveling outgoing course and storing the returning course in the form of a returning course data thereby reducing the cost for retrieving the road data stored sequentially when traveling on the outgoing course. SOLUTION: Assuming a preset outgoing course passes through roads (1) 1a→(6) 6a→(9)→(13)→(16) in this order. Since the road (1) runs in the vertical direction, the 1b direction is stored as a returning course data in an RAM when a vehicle is traveling in the direction 1a on the road (1) in order to reduce the searching cost. When the vehicle is guided to a road (9) at an intersection II, a downward load (10) closest to the road (9) is stored as a returning course data in the RAM in order to reduce the searching cost because the road (9) is a vertical one way road on which a center line 51 exists. According to the arrangement, the vehicle can be guided on a returning course identical to the outgoing course as much as possible. |
