| 摘要 |
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. |
