P4.2 - Mapping Permanent Magnets with High Angular Accuracy
- AMA Conferences 2015
2015-05-19 - 2015-05-21
- Proceedings SENSOR 2015
- P4 - Magnetic Sensors
- S. Spasic, R. Popovic - SENIS AG, Baar (Switzerland), M. Blagojevic, N. Markovic, Z. Mitrovic, L. Popovic - SENTRONIS AD, Nis (Serbia)
- 786 - 790
Modern magnetic position and angle sensors consist of a combination of a permanent magnet and a magnetic field sensor. The magnetic field of the permanent magnets used in position sensors must be mapped with high accuracy. The sensitivity vectors of the mapper’s 3-axis probe are subject to angular tolerances of a few degrees. This paper describes a method of calibration of the probe within the magnetic field mapper, which reduces the angular errors to under 0.1 degree. During the calibration, the integrated 3-axis Hall probe is placed in the Calibration Cube with the reference magnet and output voltages of the probe are read. This allows for determination of all 9 components of the probe’s sensitivity tensor. Later, while mapping a magnet, the actual magnetic field vectors are calculated by multiplying the inverse sensitivity matrix by the vector of the probe’s output voltages.