Re:Is the Kalman filter just a low-pass filter?
by defrost on Friday July 29, 2022 @12:56AM
(#32273289)
I've used it to compensate for directional measurement bias.
If you pass a moving probe through a magnetic field your meaured results vary by direction (with or perpendicular to flux) and velocity.
If you want to measure a geomagnetic field using an aircraft, the heading matters.
To normalise in post processing you calibrate a Kalman filter by flying precessing butterfly wing patterns in a known relatively level flux area and then use that to remove the magnetic signature of the aircraft and heading from data collected over multiple headings and days.
( There are a few other twists - diurnal flux and induced field from the Earths GMF interactions needs to be isolated, etc ).
If you pass a moving probe through a magnetic field your meaured results vary by direction (with or perpendicular to flux) and velocity.
If you want to measure a geomagnetic field using an aircraft, the heading matters.
To normalise in post processing you calibrate a Kalman filter by flying precessing butterfly wing patterns in a known relatively level flux area and then use that to remove the magnetic signature of the aircraft and heading from data collected over multiple headings and days.
( There are a few other twists - diurnal flux and induced field from the Earths GMF interactions needs to be isolated, etc ).