simtk.org

Hello,

I am having issues with the way the GUI (both 3.3 and 4.1) is displaying the external forces.

I have an xml (attached) where I have defined GRF (in ground) and two additional internal forces defined in the talus and tibia, respectively.

I run my ID through the Matlab API and everything seems to work fine, but when I try to visualise my external forces in the GUI by associating the mot to the ID result, the forces defined in tibia and talus are reassigned to the ground by default, see pic attached, and therefore they are misplaced.

I am able then to re-edit the external forces from the GUI and put the force back to the relevant ref sys, and I can save a new xml file which would look like the one attached (_edited).

Am I doing something wrong here? Perhaps the names I use for my forces? Or is there a bug in the visualiser?

Thanks a lot for the support

Erica

Hi Erica,

There's nothing wrong with what you're doing or your workflow. The fact is that when you associate the ground reaction forces file with the motion you don't get the opportunity to specify the xml file to do the mapping, instead you only pick the motion file. The application assumes the most common scenario that these are all ground reaction forces but you get a chance to change that afterwards. Ideally you could reuse the xml file for ExternalLoads, as is, when associating the motion but that makes for a different workflow scenario depending on the file/contents. The paradigm is to make easy tasks easy and harder tasks possible seems to work as expected here.

Please let us know if that explains or if you have any further questions,
-Ayman

Hi Ayman,

thank you very much for your reply and explaination.

I did not consider the fact that, although referenced in my ID workflow, when associating the external forces file to the motion a posteriori the xml file is not called anywhere. Everything makes sense now!

Thank you again

Erica