Modified Evolutionary Aeromagnetic Compensation Method Considering Geomagnetic Variations

Aeromagnetic compensation is essential for enhancing the accuracy of aeromagnetic measurements by estimating and eliminating magnetic interference parameters. Traditional methods typically estimate invariant interference parameters, necessitating regular calibration flights for adjustments. In our previous work, we introduced an evolutionary aeromagnetic compensation method that updates magnetic interference parameters to adapt to variant interferences. While this evolutionary approach is effective, it assumes geomagnetic invariance, which is often not the case during regular low-altitude flights where the geomagnetic field is dynamic and complex. To enhance the applicability of the evolutionary compensation method, this article presents a modified approach that accounts for geomagnetic variations. We first developed a geomagnetic field model with estimable parameters, which we then integrated with a model of magnetic interference parameters. Building on this integrative parameter model, we refined the evolutionary aeromagnetic compensation method to enable simultaneous estimation of both variable interference and geomagnetic parameters synchronously. The efficacy of our proposed method was validated through simulations and real-flight experiments. Results indicate that, in scenarios with dynamic interference and geomagnetic fluctuations, our method reduces magnetic interference from 0.941 to 0.195 nT, which is 21% better than the traditional ridge regression (TraRR) method and 16% better than the traditional evolutionary (TraEvo) algorithm from the literature.