| 摘要 |
PURPOSE:To detect the distance to the destination and the direction to the destination highly accurately in advance, by memorizing the declinations which are locally different and compensating the advancing direction of the vehicle, which is detected by a direction sensor, based on memorized value of the declination of the designated location. CONSTITUTION:A phase difference between a detected terrestrial magnetism signal from the direction sensor 1 and a reference signal is obtained in a phase detector 2. The advancing direction theta is detected, and the direction signal is sent to an operating device 5. Meanwhile, the pulse output from a running sensor 3 is inputted to a counter 4. A pulse is sent to the operating device 5 at every unit running distance. The position of the vehicle is obtained, and the distance to the destination and the direction to the destination are computed. The value of the declination alpha, which is difference for latitude is stored in a memory 10 in advance. The value is read out and imputted into the operating device. The compensation of alpha with respect to theta is applied. The highly accurate values of the direct distance to the destination and the direction to the destination, which are compensated, are displayed on a display 7. |
