Real-Time 3D Magnetometer Calibration for Embedded Systems Based on Ellipsoid Fitting

Magnetometers are massively diffused in a variety of instruments for different applications. However, these sensors are affected by non-idealities, especially bias and hard/soft-iron interference. Even though a number of calibration approaches could be adopted to compensate for magnetic interferences, their implementation on resources-constrained platforms is still problematic due to the highly complex, computationally intensive mathematical operations involved. The present work demonstrates the possibility to develop a fast and efficient 3D magnetometer calibration for real-time embedded systems with limited system resources. A number of techniques and approaches are discussed to mitigate the computational burden. Results confirm that this is achievable by preserving the same level of accuracy reached with more computationally intensive approaches. Results are also promising regarding the adoption of the discussed method on low-power real-life systems in several applications.