| 摘要 |
PURPOSE:To perform precise position detection even when geomagnetism is locally disturbed by adding the turn angle detected by a turn angle sensor to the road azimuth on a map containing the present position to calculate the proceeding azimuth of a vehicle. CONSTITUTION:The output of a geomagnetism azimuth sensor 101 is inputted to a proceeding azimuth correcting means 105. The running distance of a vehicle is obtained by a distance sensor 103. The present estimated position with respect to a reference point is obtained from the proceeding azimuth and the running distance by a present position estimating means 106. Whether a road subject to map orientation exists around the estimated position or not is judged by a map orientation calculating means 108. If not road exists, the estimated position is outputted, if the road exists, the data of the road subject to orientation are extracted from a map memory means 107, and the present position is corrected. The present position is outputted, and proceeding azimuth of the vehicle is estimated from the azimuth of the road stored in the map memory means 107 and the turn angle detected by a turn angle sensor 102. The present position is detected in sequence whenever the data of the proceeding azimuth and the running distance are obtained in the above procedures. |
