A New Method of Double Electric Compass for Localization

A new electric compass technique is proposed for localization to improve the reliability of automobile navigation system. On account of its sensitivity to external interferences of the magnetic field, the electric compass itself is not accurate enough to be used for localization compared with the rate gyroscope. To overcome this shortcoming, in this research, a robust electric compass was designed by using two electric compasses to efficiently cancel out the low-frequency interferences. That is, in this paper, a double electric compass predictive calibration algorithm which corrects irregular and long-lasting magnetic-field interferences is newly proposed and implemented. When the external interferences are eliminated from the double electric compass, it becomes much more accurate than the gyroscope-based system that suffers from accumulative drift error. The reliability and performance of the designed system were verified through real navigation experiments