Realtime Magnetometer Calibration for Spinning Aerospace Vehicles

Çetin, Mustafa Efe
Magnetometers are essential sensors for attitude estimation application in small spacecrafts due to their robust, inexpensive and lightweight characteristics. However, their direct usage is not applicable due to sensor errors. These errors limit the overall attitude estimation accuracy. This study proposes a complete real-time attitude independent magnetometer calibration algorithm for spinning aerospace vehicles. The recursive algorithm aims estimating the complete error state; consisting bias, scale factor and misalignment corrections, in real-time and without requiring any attitude information. To build the algorithm the well-known attitude-independent observation that is based on the magnitude of the sensed magnetic field is aided with new introduced quasi-measurements. The algorithm is tested with both simulations and real spacecraft data. Four quasi-measurements, which are derived using dynamic characteristics and orbital properties of the aerospace vehicle, considerably improve the convergence characteristics and estimation accuracy of the filter.


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Citation Formats
M. E. Çetin, “Realtime Magnetometer Calibration for Spinning Aerospace Vehicles,” M.S. - Master of Science, Middle East Technical University, 2022.