| 摘要 |
PROBLEM TO BE SOLVED: To use more suitable course by performing route retrieval on the basis of possibility of direction change at a transfer point, in the technique of navigation for road guidance which is mounted on a moving body like an automobile. SOLUTION: A transfer point designating part 42 designates one or two or more transfer points. A position judging part 45 and a direction change judging part 46 judge automatically whether the direction change is possible at the transfer point, on the basis of the running state of ones own car in the vicinity of each transfer point. A manual designating part 47 receives, from an input part 11, designation by a user which is concerned with the possibility of direction change at each of the transfer points. A data base reading part 48 judges whether direction change is possible at a disignated transfer point, on the basis of information previously prepared in the data base concerning whether the direction changed is possible at each transfer point. A route calculating part 43 calculates a route, on the basis of the possibility of direction change at each transfer point. |
