simtk.org

Hello,

I have used Tim Dorn's toolbox code to convert kinetic data from .mat to .mot, however, I cannot preview the .mot files written to ensure that I have preprocessed them correctly. The data I am trying to view are forces exerted on a wheelchair rim during wheelchair propulsion. Are GRFs the only forces that can be previewed in OpenSim's data previewer?

Also, I read Chapter 23, but I do not understand the difference between a .mot file and the .sto, with the exception of the time values and time column. I have various kinetic data: forces, moments, angles, stroke length, and on/off points for hand contact with the wheelchair rim. I want to ensure that I am converting the data to the appropriate OpenSim format for my model and was wondering if there are certain cases where kinetic data would need to be in .sto format as opposed to .mot format.

Thank you,

Brooke Odle

Hi Brooke,

The data previewer looks at the headers of the .mot file and use those to decide where to draw the arrows representing the forces. The format has changed over time, particularly now that column labels are required to be unique (as of version 2.3.2 beta). Please consult the latest user guide and let us know if you continue to have questions.

The .mot file is a SIMM file format, it is very similar to our .sto files except that our .sto files have different header and a version number, and some other minor differences (e.g. angles could be in radians or degrees depending on the header while .mot files are assumed to be in degrees, also labels are unique and the files must have a time column). Again this has been mostly documented in the latest user guide so please let us know if you have questions.

All the best,
-Ayman

Hi,

I'm using OpenSim version 3.1. I can preview the old *.mot files fine. Force vectors for both sides are drawn.
For the unique label *.mot file only the first set of forces is drawn; the ones without the prefix.
Am I missing something here?

Hi Brooke
I'm facing a lot of issues processing my motion data in opensim. I was using lee-son tool box to convert my c3d files to .trc and .mot format, but I think this toolbox did not convert them in a proper opensim format. today I download Tim dorn's toolbox to convert my data but did not work for me. since you already used this tool box coud you send a quick explanation or some tips of how to use the toolbox.
thanks
abeer