| 摘要 |
PURPOSE:To recognize that a vehicle is deviated from a guidance path by outputting an alarm signal when the vehicle is deviated from the guidance path. CONSTITUTION:A storage means 12 stores necessary information including a map for travel guidance. Then, an electric wave from a satellite is received by a receiver of a position system (GPS) of a present place detection means 14 to detect the present position of the vehicle. A control means 16 receives the signal and controls the means 12 based on an operated result and performs the processing such as displaying stored information. Especially, the alarm signal is outputted when the vehicle is deviated from the guidance path on the way to guide the vehicle to a specific target place by the means 16. For instance, a prescribed distance area (d) with the intersection center (C) as a center is set and the coordinates when the vehicle enters and gets out of the area are stored and an angle formed by the intersection center (C) and the coordinates of the above-mentioned two places is calculated and compared with the angle in the correct path and the correctness or wrongness of the path is decided and if wrong, a warning is announced with a voice that 'I took the wrong road'. |
