| 摘要 |
PURPOSE:To secure a chance to correct the output of an azimuth sensor even when the current position is estimated by taking in the output of the azimuth sensor at a high speed. CONSTITUTION:Two tracks are generated by connecting alternate estimated positions Pi (i=1, 2...) estimated on the basis of the outputs of a distance sensor and the azimuth sensor. When a vehicle turns, the time difference DELTAtheta between the tracks is nearly zero, but when the vehicle is turning, the time difference DELTAthetaexceeds a threshold value thetath. For the purpose, this difference DELTAtheta is decided by using the threshold value thetath to detect a straight travel. The points Pi are connected by turns, so the sensitivity of the straight travel decision for the azimuth sensor output is decreased and it is hardly decided that the vehicle is in process of turning owing to the passing of a pedestrian. The two tracks are used, so the position precision can be improved by the high-speed detection. |
