Xsens MTi-30 AHRS, User Manual

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10 Document MT0605P.2018.E
© Xsens Technologies B.V. MTi User Manual

C: DLL example

C++: public source example and DLL example
 Example source code and examples (Linux)

C-example

C++-public source example
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Magnetic Field Mapper – MFM (Windows and Linux)
 MFM SDK (Windows and Linux)
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Documentation

MTi User Manual [MT0506P]
 MTi 1-series Data sheet [MT0512P]
 MTi-3 DK User Manual [MT0513P]
 MT Low Level Communication Documentation [MT0101P]
 MT Magnetic Field Mapper Documentation [MT0202P]
 XDA doxygen HTML API documentation
 MTi Whitepaper
 Firmware Updater User Manual [FU0100P]
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Firmware Updater (Windows)
NOTE : the most recent version of the software, source code and documentation can always be
downloaded on www.xsens.com/mt-software-suite . Links to documentation can be found on BASE:
https://base.xsens.com/hc/en-us/articles/207003759
3.5 Installation
3.5.1 Transient accelerations
The 3D linear accelerometers in the MTi are primarily used to estimate the direction of gravity to obtain
a reference for attitude (pitch/roll). During long periods (more than tens of seconds) of transient “free”
accelerations (i.e. 2
nd derivative of position) the observation of gravity cannot be made. The sensor
fusion algorithms can mitigate these effects to a certain extent, but nonetheless it is impossible to
estimate true vertical without additional information.
The impact of transient accelerations can be minimized when you take into account a few things when
positioning the device when installing it in the object you want to track/navigate/stabilize or control.
If you want to use the MTi to measure the dynamics of a moving vehicle/craft it is best to position the
measurement device at a position close to the centre of rotation (CR) of the vehicle/craft. Any rotations
around the centre of rotation translate into centripetal accelerations at any point outside the center of
rotation. For the MTi-G-710 with a valid GNSS-fix, the detrimental effect of transient accelerations on
orientation estimates is overcome by integrating with GNSS measurements in the sensor fusion engine.
The MTi 100-series copes better with transient “free” accelerations because of the higher-class
gyroscopes in the MTi 100-series. Next to the better hardware, the algorithm in the MTi 100-series is
superior in detecting and coping with challenging conditions, such as transient accelerations.
3.5.2 Vibrations
The MTi samples IMU signals at 10kHz per channel, processing them using a strapdown integration
algorithm with coning/sculling compensation. Proper coning/sculling compensation already mitigates
errors that poorly designed signal processing pipelines introduce when the device is under vibration. For
best results however, it is recommended that the MTi be mechanically isolated from vibrations as much
as possible: since vibrations are measured directly by the accelerometers, the following two conditions
can make the readings from the accelerometers invalid;