Method and apparatus for improving dead reckoning distance calculation in vehicle navigation system
US6360165B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 21, 1999 |
| Grant date | Mar 19, 2002 |
| Priority date | — |
| Expiry date | Oct 21, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C21/28
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention enables a vehicle navigation system to automatically compensate for odometer measurement errors due to changes in tire size and/or slip, and to avoid odometer recalibration when slip is present. These capabilities improve the accuracy and reliability of the vehicle navigation system. Slip of a vehicle, e.g., a loss of traction, can occur when a road is wet or covered with snow or ice. It can occur when a road is dry, and a vehicle is accelerating or decelerating rapidly. It can occur rounding a sharp corner. Because an odometer is typically hooked up to a driven wheel, the engine or transmission, there may be large sources of error in the distance estimates derived from the odometer. Utilizing conveniently derived slip signals from an anti-lock brake system (ABS) or from a traction control system (TCS), the slip of the vehicle can be accounted for, even absent a GPS signal to recalibrate the system. This allows for improved accuracy of the system which is particularly noticeable in urban environments where GPS signals may not be available.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.