User Manual

© Xsens Technologies B.V.
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inside the MTw inaccurate. Performing a Magnetic Field Mapping on the MTw may recover
the calibration if the magnetization is not too strong.
3.3.2 Settling Time
As with all filters of its kind, the XKF-3w filter is based on history. For this reason, some time
is needed for the XKF-3w filters to settle to a stable state, this is referred to as “settling
time”. Users should be aware that prior to a measurement, the MTw’s should be allowed to
reach some filter stability. In practice this means, that users should try to minimise
movement when making a wireless connection. Furthermore, depending on the update rate,
users should minimise movement, or keep any movements to calm and slow movements for
the first few seconds, to one minute after entering measurement mode.
3.3.3 Operating Conditions
The MTw has been designed to be used or worn close to the human body. Take care when
exposing the MTw to strongly deviating environmental conditions. The recommended
operating temperature is between -20°C and +55°C ambient temperature. If operated
outside this temperature range performance may decrease or the device may become
damaged. Fast transient temperature fluctuations may cause significant temperature
gradients across the device. Such gradients cannot be properly modelled by temperature
compensation and may therefore decrease performance. Additionally, operating around 0
o
may cause water particles to freeze and condense around the components, causing potential
damage to the internal electronics. For optimal performance, the ambient temperature
should remain as constant as possible during the measurement. Cold environments may
provide shorter operation time of the trackers.
The MTw and Awinda Station must be kept dry at all times. Condensation and water may
damage the internal electronics. Using the MTw with the straps will protect the MTw to
body moisture to a limited degree.
Protect the MTw from violent handling such as drops on hard surfaces. Excessive shocks or
violent handling may damage the MTw or render the factory calibration no longer
applicable. When handling the MTw at a desk, it is advised to place cushioning material
between the desk and the MTw.
Do not put MTw’s in the pockets in the suit case while in operation. Due to the high thermal
insulation of the foam then surrounding the MTw the device will not be able to dissipate the
small amount of heat that it generates during operation and it may become (too) hot.
3.3.4 Absolute Maximum Ratings
Stresses above the absolute maximum ratings to the MTw may cause permanent damage to
the device components.