The MVNX (Moven Open XML format) files contains 3D position, 3D orientation, (and optionally; 3D acceleration, 3D velocity, 3D angular rate, 3D angular acceleration) of each segment (not the sensors) in XML format (ASCII). The following documentation is extracted partially from the XSens original documentation and by review of example files. There are still open point with unknow undocumented behavoir.

The MVNX file starts with a version number:

<mvnx version="2">

The <mvnxInfo> section contains information about the number of frames, the frame rate, recording date, original MVN file, and the contents of velocity, acceleration, angular velocity or angular acceleration data.

<mvnxInfo frameCount="1000"
 frameRate="100"
 recDate="0"
 originalFilename="c:\data\session‐001.mvn"
 velData="1"
 accData="0"
 angVelData="1"
 angAccData="0"/>