Current position calculating system having a function for correcting a distance factor
US5899954A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 9, 1996 |
| Grant date | May 4, 1999 |
| Priority date | — |
| Expiry date | Apr 9, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C21/30
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A current position calculation system is provided for adequately correcting a distance factor which is used for obtaining a travelled distance by utilizing various information at the time when a vehicle turns left or right. According to an output from a headed direction detecting device, an output from a travelled distance calculating device and road data of a road map, at the time when the vehicle turns left or right from a first road to a second road, there is obtained a distance error amount d which is an error in an output from the travelled distance calculating device with respect to an actual value it should be. The distance error amount d is corrected so as to be reduced. In order to obtain the distance error amount d, a moving path of the vehicle position is estimated without considering whether the position is on or off a road after completing the left or right turn, it is checked whether the estimated moving path of the vehicle position is an overshoot or an undershoot with respect to the second road on the road map, and the amount of the overshoot or the undershoot is obtained as the aforementioned distance error amount d.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.