| 摘要 |
PROBLEM TO BE SOLVED: To prevent a vehicle from coming in an off-route state whereby the vehicle comes out of a new route immediately after a re-searching by researching the new route with minimum re-reach time, when the vehicle goes off a route which was last obtained by the results of research while the vehicle is running. SOLUTION: A route L1 is searched by a first search from a start position to a destination. When a vehicle goes off the route L1 obtained by the first research, a second research is performed by the operation of a re-search switch 45 to obtain a second search route L3 to a point Q2 on the first route L1 from the current position P2 of the vehicle. When the vehicle comes out of the second search route L3, a third search new route L4 to a point Q5 in the search route L3 obtained last is obtained from the current point P4 of the vehicle. Thus, when the vehicle goes off the route L3 as the result of search used currently by the vehicle, namely, the route L3 as the results of search obtained last, the new route L4 ranging from the current position of the vehicle to the route L3 as the result of search obtained lastly is searched from the current position of the vehicle. |
