| 摘要 |
PURPOSE:To judge a route deviation in any point other than a crossing, to reduce the time-lag between the generation of the route deviation and its judgment and to make an apparatus low-cost. CONSTITUTION:A distance allowable error + or -d as an allowable range in which a route deviation is not judged to exist is computed, the rectilinear distance G between a present position obtained by a position detection device measuring the position of a vehicle and a crossing as an object is computed, a remained running distance (X-Y) which has subtracted a run distance Y from a journey distance X up to a next crossing in route search data is computed, the distance allowable error + or -d is added to the running residual distance (X-Y), and a running actual residual distance L=X-Y+ or -d is obtained. When the rectilinear distance G is larger than the running actual residual distance L, the route deviation is judged to exist. The number of route deviations is counted in order to increase the reliability of the route deviation. When it is judged that the number of route deviations is a prescribed number or higher, a route deviation flag is produced, and the route deviation is judged. |
