| 摘要 |
PURPOSE:To dispel driver's feeling of incompatibility and uneasiness at the time of navigation running by displaying the going state of his own vehicle only based on recognition data of a second vehicle going speed recognizing means in the case of loss of the recognizing function of a vehicle going direction recognizing means like a terrestrial magnetism sensor. CONSTITUTION:A vehicle position recognizing device 4 which recognizes the present user's own vehicle position consists of a terrestrial magnetism sensor 41, a wheel speed sensor 42, and a signal processing circuit 43 which receives outputs from both sensors 41 and 42 and detects the going direction of the vehicle and the relative distance from a prescribed reference point to recognize the present vehicle position. If the vehicle runs not on a general road but on an iron bridge or the like where the normal terrestrial magnetism cannot be obtained, the going direction is inferred and determined only based on the change of the output of the wheel speed sensor 42, and a vehicle position mark MA is displayed on a CRT 6 to continue the navigation running in form. Thus, the driver does not feel incompatibility or uneasiness though his vehicle passes on the iron bridge or the like where the terrestrial magnetism sensor 41 cannot be used. |
