simtk.org

Hi,

While performing inverse dynamics analysis when I define the external load and run the analysis the software crashes. However, when the same model is run using the external force set xml file written using the above definition of load, the analysis runs fine. Is there any bug of such sort?

Also, when I check the external force set xml file I just see the Natural Cubic Spline data for 0.15s when actually the simulation lasts for 2s. Shouldn't the file contain the spline data for entire 2 sec.

Thanks.

Hi Priyanshu,

To keep backward compatibility with how external forces were applied prior to 2.0, we do some conversion on the fly when loading old setup files. For this conversion to work you had to have the tool setup correctly to use exactly 2 external forces with specific column labels as described in the old user guide.
If you create the external forces xml file fresh from the GUI then this shouldn't be an issue.

Since we shouldn't crash regardless (but instead issue a diagnostic error message) please file a bug and attach all the files necessary to reproduce the crash with details on how these files were created.

The spline data in the external forces file do not matter since the splines are constructed from the storage file based on the column labels so I wouldn't worry about the actual data points in the file.

Hope this explains,
-Ayman

Thanks for the help Ayman. I will file the bug.