Abstract:

Digital magnetic heading measuring system (DMHMS) is an essential device of modern unmanned aerial vehicles(UAV).The accuracy of the system itself is high enough,but the error caused by ferro material onboard(called magnetic deviation)is unavoidable due to the small size of UAV.This paper studies magnetic deviation compensation for arbitrary attitudes of UAV equipped with DMHMS.After analyzing the cause of deviation,an algorithm,which is able to eliminate the errors influenced by ferro material onboard before heading computation,is used to decrease computation.Deviation coefficients required in the algorithm are obtained from experiment mentioned in the paper in details.The correctness of the deviation coefficients can be examined by a computer so that there is no need of experiment repeated.In order to avoid confusion in the experiment data, a method which can find mistakes in experiment data is proposed.The methods discused in the paper have been successfully used in some UAV which needs deviation compensation in arbitrary attitudes. It can be used not only in UAV but also in other vehicles such as cars and ships.

Key words: unmanned aerial vehicle, heading measurement, magnetic compass, magnetic deviation