FP Coordinates
Posted: Wed Jun 24, 2015 9:40 am
Thank you for the release of v.2.2. This have made life easier for data extraction from c3d files. I have a confusion on what coordinate system to be used for rotation of the Force plates in the laboratory setup.
I have made my own laboratory setup file for acquisition. The coordinate system being used in the laboratory is defined as : <CoordinateSystemOrientation>YZX</CoordinateSystemOrientation>
This have been given as per the guidelines in the user manual. Now for defining the coordinates of FP, should I consider this (YZX) as my global coordinate or should I consider the OpenSim coordinates (XYZ) as global coordinates for the rotations defined inside <FPtoGlobalRotations>
I was using my laboratory coordinate as the global coordinate and rotated the force plates with respect to that. While performing the RRA in OpenSim my model was sinking downwards and the masses suggested for body segments are in negative. This raised the suspicion whether it could be due to the incorrect definition of coordinates to FP in data acquisition. It would be really great if your help me figure it out.
I have made my own laboratory setup file for acquisition. The coordinate system being used in the laboratory is defined as : <CoordinateSystemOrientation>YZX</CoordinateSystemOrientation>
This have been given as per the guidelines in the user manual. Now for defining the coordinates of FP, should I consider this (YZX) as my global coordinate or should I consider the OpenSim coordinates (XYZ) as global coordinates for the rotations defined inside <FPtoGlobalRotations>
I was using my laboratory coordinate as the global coordinate and rotated the force plates with respect to that. While performing the RRA in OpenSim my model was sinking downwards and the masses suggested for body segments are in negative. This raised the suspicion whether it could be due to the incorrect definition of coordinates to FP in data acquisition. It would be really great if your help me figure it out.