| 摘要 |
PURPOSE:To accurately detect the vehicle position and its running direction. CONSTITUTION:This invention is applied to a position detector for vehicle that is provided with a car speed sensor 1, bearing sensor 2, GPS receiver 3 and CPU 5, and the CPU 5 measures the number of car speed pulses outputted from the sensor 1 at fine time interval. The vehicle position and its running direction are detected at about 100msec intervals through the car speed pulse and the output of the sensor 2. Further, the CPU 5 performs GPS measurement at about 1 second intervals. The GPS measurement is performed to estimate the respective reliabilities of the vehicle position and its running direction obtained by the GPS signals. The vehicle position and its running direction are corrected based on the reliabilities. Thus the vehicle position and its running direction can be obtained accurately. |
