| 摘要 |
PURPOSE:To offer the on-vehicle navigation which copes with cases wherein a vehicle travels in an area outside the range of map data and wherein no storage medium is loaded when the necessary map data are read in by providing a device which detects the absolute position of the vehicle from latitude and longitude information. CONSTITUTION:The detection output of a GPS device 4 for detecting the absolute position of the vehicle from the latitude and longitude information is supplied to a system controller 5. The system controller 5 is equipped with a CPU (central processing circuit) 7 which calculates the travel distance, travel azimuth, current position coordinates (longitude and latitude), etc., of the vehicle according to output data of respective sensors 1 - 4. When a no-map travel module is processed, the CPU 7 judges whether or not the GPS device 4 is connected to an interface 6 and estimates the current value of the vehicle according to the output data of the azimuth sensor 1 and distance sensor 3 unless the GPS device 4 is connected to display both the travel azimuth and travel track of the vehicle on a display. |
