Problem with model scaling

[Lauri Stenroth]

Hi,

I'm having a problem with model scaling. I'm able to scale the model based on measurements taken from marker pairs but the scale tool failes as it tries to adjust model markers. Below is the error message that I get. Can anyone help?

java.lang.RuntimeException: AssemblySolver::assemble() Failed: SimTK Exception thrown at Assembler.cpp:871:
Method Assembler::assemble() failed because:
Optimizer failed with message: SimTK Exception thrown at InteriorPointOptimizer.cpp:261:
Optimizer failed: Ipopt: Infeasible problem detected (status 2)
Assembly error tolerance achieved: 0.00588688227992556 required: 1e-005.
at org.opensim.modeling.opensimModelJNI.OpenSimContext_processModelMarkerPlacer__SWIG_0(Native Method)
at org.opensim.modeling.OpenSimContext.processModelMarkerPlacer(OpenSimContext.java:329)
at org.opensim.tracking.ScaleToolModel$ScaleToolWorker.construct(ScaleToolModel.java:348)
at org.opensim.swingui.SwingWorker$2.run(SwingWorker.java:108)
[catch] at java.lang.Thread.run(Thread.java:745)

[Thomas Uchida]

The error message means that the AssemblySolver is unable to find a solution (i.e. model pose) in which the model markers are aligned with the experimental markers (see the "Marker Placement" section here: https://simtk-confluence.stanford.edu:8 ... rPlacement).

You might want to check out the YouTube video here: "OpenSim Webinar: Tips and Tricks for Data Collection, Scaling and Inverse Kinematics in OpenSim", https://www.youtube.com/watch?v=ZG7wzvQC6eU

There are also two instructional videos at the bottom of this page: https://simtk-confluence.stanford.edu:8 ... th+Scaling

[Lauri Stenroth]

Thanks you, Tom!

There was a problem with the marker data. After recreating the trc-file scaling worked normally.

-Lauri