AN3192 Magnetic Sensor Calibration Method

[oleg_sidorovich_1981]

Help me? I don't understand how has obtained vector X (Equation 27-29, page 28-29, AN 3192)?

[Eleon BORLINI]

Hi oleg, equation 27 is the matricial transcription of equation 26 (which is the equation of a 3D sphere): same equation, but under different shape and with x^2 explicit before the = sign. The meaning of w and X for equation 28 and 29 is inspired to Appendix B (accelerometer) section

• Matrix X is the calibration parameters that need to be determined
• Matrix w is sensor raw data LSBs collected at stationary positions

and equation 29 (which is eq. 28 "transposed") enables you to get the calibration parameters (vector "X") from the "w" sensor raw data, using H matrix for the conversion. It's only an algebraic transformation, you should not need these two equations in a practical application or compensation.

Regards

[oleg_sidorovich_1981]

Why you said "Matrix w is sensor raw data LSBs collected at stationary

positions" if "After three 2D full round rotations magnetic sensor raw data have been collected,

it is possible to combine Mx, My, and Mz as column vector and row vector"[AN3192,page 28, under equation 27]? How you can explaine this? 

I must do three 2D full round rotations magnetic sensor. What to do with this raw data?