Monitoring accuracy of an electronic compass
US6539639B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 6, 2000 |
| Grant date | Apr 1, 2003 |
| Priority date | — |
| Expiry date | Dec 8, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01C17/38
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A three-axis physical model is used to numerically compensate for errors in measured magnetic field values in an electronic compass for operation at any orientation. This compensation method generates certain quantities that characterize the magnetic field of the Earth in the vertical plane. These quantities are used to monitor the accuracy of the electronic compass during normal operation by comparing their current values either with values obtained during the calibration procedure or with values obtained from historical averages. Significant departure from the calibration values or from the historical averages indicates a probable loss of accuracy of the compass, and the user is so alerted.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.