DMU380ZA Series
User’s Manual
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Doc# 7430-3810 Rev.02
Page 89
The AHRS and INS380ZA products can actually measure the constant magnetic field that
is associated with your system and correct for it. The AHRS and INS380ZA products can
also make a correction for some soft iron effects. The process of measuring these non-
ideal effects and correcting for them is called
the “Mag Alignment Procedure”.
Performing a “Mag Alignment Procedure”
will help correct for magnetic fields that are
fixed with respect to the DMU380ZA Series product. It cannot correct for time varying
fields, or fields created by ferrous material that moves with respect to the DMU380ZA
Series product.
The AHRS and INS380ZA products account for the extra magnetic field by making a
series of measurements, and using these measurements to model the hard iron and soft
iron environment in your system using a two-dimensional algorithm. The AHRS and
INS380ZA products will calculate the hard iron magnetic fields and soft iron corrections
and store these as calibration constants in the EEPROM.
The “Mag Alignment Procedure”
should always be performed with the AHRS or
INS380ZA product installed in the user system. If you perform the calibration process
with the DMU380ZA Series product by itself, you will not be correcting for the
magnetism in the user system. If you then install the DMU380ZA Series product in the
system (i.e. a vehicle), and the vehicle is magnetic, you will still see errors arising from
the magnetism of the vehicle.
Mag Alignment Procedure Using NAV-VIEW
The Mag Alignment Procedure using NAV-VIEW can be performed using the following
steps below:
1.
Select “Mag Alignment” from the “Configuration” drop down menu at the
top.
2.
If you can complete your 360 degree turn within 120 seconds, select the
“Auto
-
Terminate” box.
3.
Select the “Start” button to begin the “MagAlign” Procedure and follow the
instructions at the bottom of the screen as shown in Figure 27 below.
