| 摘要 |
PURPOSE:To display the current position of a vehicle correctly by regarding the 1st passing point specified in road map data as an origin when the vehicle passes the 1st passing point, finding an azimuth error from the current position which is already calculated and the coordinates of the 1st and the 2nd passing points when the vehicle reaches the 2nd passing point, and correcting the detected traveling azimuth. CONSTITUTION:Two proper points in the road map data, i.e. points A and B are specified as a start and an arrival point for the correction and the point B is registered previously. Then a driver registers the point A when the vehicle passes the point A. When the vehicle reaches the point B, the driver presses a correction point arrival SW. At time, the position of the vehicle which is calculated from the outputs of a distance sensor and a terrestrial magnetism computer 120 is denoted as B'. Here, the azimuth error between the azimuth theta1 between the points A and B and the azimuth between the points A and B' on the road map includes the angle of deviation of the terrestrial magnetism and the fitting angle error of the terrestrial magnetic sensor. An on-vehicle navigator, therefore, finds the azimuth error theta by utilizing the coordinates of the points A, B, and B'. Then, the azimuth signal thetaS from the CPU 120 is corrected with the azimuth error theta to find the accurate current position of the vehicle. |
