Converting from c3d to trc without force plates

[Radhakrishnan Vignesh]

Hello,

Sorry to disturb but I have gait data in both static and dynamic trials collected on a normal treadmill in .c3d format. There is no force plate data which is causing functions like c3dExport.m to crash when I try to convert it to .trc files. How do I go about this?

Thanks, and Regards
Vignesh

[Ayman Habib]

Hi Vingesh,

Similar issue (where missing forces resulted in a crash rather than an empty table) has been fixed in early 2020 and integrated into version 4.2, can you test your code in version 4.2+ and let us know what you find out?

Thanks,
-Ayman

[Radhakrishnan Vignesh]

Hello Ayman,

Thank you for your reply. I have OpenSim version 4.2 and I installed it early this year. Would the changes have been implemented by then? Just for reference I get this error whenever I run c3dExport.m on any static file

c3dExport.JPG (42.27 KiB) Viewed 133 times

Thanks, and Regards
Vignesh

[Ayman Habib]

Hello Vignesh,

The error here is that c3dExport does not check that the forces table is empty and regardless goes on to ask for more data about the forces (e.g. forceRate) which is incorrect since the table is empty. It would be great if you can fix that on your side (handle empty forces table) and file a bug with an example .c3d file that contains no forces so we can fix the distributed script moving forward. If you can also post to this trail with what changes you needed to make that would be helpful to other users of c3dExport on this forum.

Please let us know if you need further help or run into other issues in the process.

Best regards,
-Ayman

[Radhakrishnan Vignesh]

Hey Ayman,

I shall work on this after the 16th. Thanks and shall let you know if I need any assistance regarding the same.

Regards,
Vignesh