| 摘要 |
PURPOSE:To accurately find the position and speed of a vehicle even when GPS measurement is impossible. CONSTITUTION:The position detector for vehicle is provided with a GPS receiver 3, an acceleration sensor 4, and a CPU5, and the CPU5 judges whether or not GPS measurement is possible by interruption and, when the GPS measurement is possible, calculates the position, azimuth, and speed of its own vehicle on the basis of GPS signals and, at the same time, calculates the error factor for bringing the output of the sensor 4 close to real acceleration by using the speed calculated on the basis of the GPS signals and corrects the output of the sensor 4 based on the results. When it is judges that the GPS measurement is impossible, the CPU5 calculates the position, etc., of its own vehicle based on the results obtained by correcting the output of the sensor 4 by using the error factor on the basis of position, etc., of the vehicle calculated on the basis of GPS signals immediately before the GPS measurement has become impossible. Therefore, the position, etc., of the vehicle can be accurately found even when the GPS measurement is impossible. |
