| 摘要 |
PURPOSE:To improve the azimuth detection accuracy by using absolute azimuth data when a state wherein only a relative azimuth sensor is used continues for a specific distance or time and it is judged that relative azimuth data easily becomes erroneous. CONSTITUTION:When the state wherein the data of an earth magnetism sensor 12 is not used at all and only the data of the relative azimuth sensor such as an optical fiber gyro 13 or vibration gyro 14 is used for azimuth estimation continues for the constant travel distance or time and it is judged from output data the vehicle is under travel conditions where the relative azimuth data easily become erroneous, a locator 1 fetches the data of the earth magnetism sensor 12 and the azimuth of the vehicle which is found so far is reset and replaced with the mean value of the data of the earth magnetism sensor 12 to detect the position of the vehicle. Consequently, the accumulation of an error due to the continuous use of only the relative azimuth data is eliminated and the azimuth detection accuracy is improved. |
