MTi 1-series User Manual
Xsens MTi User Manual Repository
Datasheet
Copyright © 2021 Xsens
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compensates for both hard iron and soft iron distortions.
The magnetic field mapping (calibration) is performed by moving the MTi together with the
object/platform that is causing the distortion. The results are processed on an external
computer (Windows or Linux), and the updated magnetic field calibration values are written to
the non-volatile memory of the MTi 1-series module. The magnetic field mapping procedure is
extensively documented in the
Magnetic Calibration Manual.
In-run Compass Calibration (ICC)
In-run Compass Calibration is a way to calibrate for magnetic distortions present in the sensor
operation environment using an onboard algorithm. The ICC is an alternative to the offline MFM
(Magnetic Field Mapper). It results in a solution that can run embedded on different industrial
platforms (leaving out the need for a host processor like a PC) and relies less on specific user
input. The MFM tool, which does require a host processor, is, however, still recommended over
or in addition to the ICC. The ICC is aimed at applications for which the MFM solution cannot be
used (e.g. MTi 1-s that is not able to be connected to a PC), when MFM is not sufficient (e.g.
applications that move outside of the plane of motion used during the calibration), or when the
user uses the same MFM result performed for one sensor to calibrate different sensors (typical
for large volume applications).
It should be noted that magnetic distortions present in the environment of the motion tracker
that move independently or change over time are not compensated by the ICC unless they are
changing very slowly. Such distortions do not affect the parameter estimation; they are simply
not compensated for. This also means that (ferromagnetic) objects should not be attached to
or detached from the sensor while ICC is running.
If the user is able to perform a calibration motion in a homogeneous magnetic field or
environment that is representative of the application, then it is possible (and recommended) to
use the "Representative Motion" feature (RepMo). RepMo is available in MT Manager, XDA and
Low-Level Communication Protocol (Xbus protocol).
Additional details are available on BASE.
Active Heading Stabilization (AHS)
The Active Heading Stabilization (AHS) is not a magnetic calibration procedure, but a software
component within the sensor fusion engine designed to give low-drift unreferenced heading
