Xsens MTi 1 Series, Руководство пользователя

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MTi 1-series User Manual
Xsens MTi User Manual Repository Datasheet
Copyright © 2021 Xsens Page 37
The table below reports the different filter profiles the user can set based on the application
scenario. Every application is different, and results may vary from setup to setup. It is
recommended to reprocess recorded data with different filter profiles in MT Manager to
determine the best results in your specific application.
Filter profiles for MTi-7/8 (GNSS/INS)
Name GNSS
#1
Barometer
#1
Magnetometer Description
General / General_RTK • • This filter profile is the default setting. Yaw is North referenced (when
GNSS is available). Altitude (height) is determined by combining static
pressure, GNSS altitude and accelerometers. The barometric baseline is
referenced by GNSS, so during GNSS outages, accuracy of height
measurements is maintained.
GeneralNoBaro /
GeneralNoBaro_RTK
• This filter profile is very similar to the general filter profile except for the
use of the barometer.
GeneralMag / GeneralMag_RTK
#2
• • • This filter profile bases its yaw estimate mainly on magnetic heading and
GNSS measurements. A homogenous or magnetic field calibration is
essential for good performance.
[1] External aiding sensors for the MTi-7/8
[2] This filter profile can be used even when the barometer is not part of the design.
Magnetic interference
Magnetic interference can be a major source of error for the heading accuracy of any AHRS. As
an AHRS uses the magnetic field to reference the dead-reckoned orientation on the horizontal
plane with respect to the (magnetic) north, a severe and prolonged distortion in that magnetic
field will cause the magnetic reference to be inaccurate. The MTi 1-series module has several
ways to cope with these distortions to minimize the effect on the estimated orientation.
Magnetic Field Mapping
When the distortion moves with the MTi (i.e. when a ferromagnetic object solidly moves with
the MTi module), the MTi can be calibrated for this distortion. Examples are the cases where the
MTi is attached to a car, aircraft, ship or other platforms that can distort the magnetic field. It
also handles situations in which the sensor has become magnetized. These types of errors are
usually referred to as soft and hard iron distortions. The Magnetic Field Mapping procedure