| 摘要 |
PURPOSE:To improve accuracy of a navigation system by retrieving surrounding road information in case there is no road information at a scheduled place of a next trace point and moving the trace point on the most adjacent road information. CONSTITUTION:The road information is stored in a sub-code of a compact disc (CD) as graphic data and read in a screen memory V-RAM 2 and displayed on a CRT. There are topographic data besides this in map information stored in the CD and these are also read in a screen memory V-RAM 1 and displayed on the CRT. The trace screen stores one by one a locus of the trace point showing the current position of a vehicle in a screen memory V-RAM 3. But when the next trace point 2 is deviated from the road information, the next trace point is moved on the most adjacent road information 3 in the surroundings. The inconvenience that the actual trace point is gradually separated from the road information can be prevented by performing such correction one by one. |
