| 摘要 |
PURPOSE:To eliminate strange feeling of user by comparing the actual running distance of a vehicle with the moving distance between estimated positions and when a decision is made that the moving distance is longer by a prescribed value or more than the running distance, inhibiting the display/memory of running track at that part. CONSTITUTION:Map matching is effected based on the running distance of vehicle determined by a distance sensor 2, the orientation of vehicle determined by an orientation sensor 1, and a road layer read out from a CDROM 7. An estimated position thus calculated is then compared with a position measured by a CPS receiver and corrected. Subsequently, a vehicle mark is displayed and the distances to current and previous estimated positions are determined and compared with the running distance. If the difference is larger than a prescribed value, a decision is made that the moving distance is abnormal and only the vehicle position is displayed on the map and the display/memory of track is inhibited. This constitution eliminates presentation of a running track causing strange feeling for the user when a significantly erroneous estimation of vehicle I position is made. |
