Automated Estimation of Magnetic Sensor Position and Orientation in Measurement Facilities

In the present article, we propose, present and validate a concrete methodology for automating the calibration process of the magnetic field sensors in a measuring facility. The calibration process involves the dc field measurements of a well-characterized magnetic source and the modeling of its signature with multiple dipoles before the execution of the measurement campaign. Then, the signature of the calibration source is measured from various orientations, producing different spatial patterns of the dipole magnetic field. The measured dataset, along with the parameters of the source are employed by the calibration algorithm to optimize the position and alignment of the field sensors. To evaluate the accuracy levels of the developed calibration methodology, we use real measurements generated by two different current-fed coils for low-range and larger-distance placement of the sensors. In addition, we outline the practical implementation of the calibration process in two different facilities used for measurements and characterization, namely a multimagnetometer facility and a facility that performs unit rotation. The experimental results verify the capability of our method to estimate the position and orientation of the sensors, achieving position accuracy levels below 5 mm and a maximum orientation deviation of 2$^\circ$.