Automate plotting of motion

[Joel Quarnstrom]

Hello,

I am very new to OpenSim and object oriented programming in general. I am trying to write a script in the GUI to plot muscle tendon length for the Biceps Long Head muscle vs results. I have a model and motion file. I have been able to plot this manually, but I am looking for a way to automate the process.

The main thing I am trying to figure out is how to utilize the results of a motion file in the GUI scripting, and plot it against a muscle.

I attached a screen shot of the plot that I am trying to recreate through a script.

Thank you,
Joel

[Thomas Uchida]

I have been able to plot this manually, but I am looking for a way to automate the process.

There are example scripts in your OpenSim installation directory, under Resources\Code\GUI (e.g., C:\OpenSim4.0\Resources\Code\GUI):
- plotMuscleFiberLengthAgainstFile.py
- plotMuscleMomentArmAgainstMotion.py
If you haven't already, you can install these example files (models, scripts, etc.) by typing installResources() in the Scripting Shell. The scripts can also be viewed here: https://github.com/opensim-org/opensim- ... im/Scripts.

[Joel Quarnstrom]

I have been looking through those documents, but I am unsure how to use results with those commands. Do you know how to reference the results of a motion with the plotting commands?

[Thomas Uchida]

Please see the "Scripting in the GUI" page in the Confluence documentation (https://simtk-confluence.stanford.edu:8 ... in+the+GUI). There are links to the following doc pages under the "Interacting with the GUI (including the Plotter)" heading:
- https://simtk.org/api_docs/opensim/gui_ ... otter.html
- https://simtk.org/api_docs/opensim/gui_ ... e/gui.html
The last link lists getCurrentMotion() here: https://simtk.org/api_docs/opensim/gui_ ... ntMotion--.

[Joel Quarnstrom]

I looked at those links and had some success, I was able to create a plot of a muscle fiber-length against a joint angle, but I was unable to plot the fiber-length against the results. Here is my code, and a screen shot of the plot.
Here is my code:


loadModel("D:\Oklahoma State University\Research on Stroke device\OpenSim\My Stuff\Fourbarmodel.osim");

plotterPanel = createPlotterPanel("Plot Example")

motionfilePath = "D:\Oklahoma State University\Research on Stroke device\OpenSim\My Stuff\Arm motion 6-17-2019.mot";
motSrc = addMotionSource(plotterPanel, motionfilePath)

motiondata = addDataSource(plotterPanel, motionfilePath)

Motion = loadMotion(motionfilePath)

currentmotion = getCurrentMotion()

Curve = addAnalysisCurve(plotterPanel, "fiber-length" , "BIClong", "elbow_flexion")



The I also changed the last line to:

Curve = addAnalysisCurve(plotterPanel, "fiber-length" , "BIClong", "Results(Deg.)")

But it didn't produce a graph at all.

Do you know how to use the results from a motion with the addAnalysisCurve function?

Thank you,
Joel

[Thomas Uchida]

Have you tried addCurve()? It's listed below addAnalysisCurve() in the documentation: https://simtk.org/api_docs/opensim/gui_ ... otter.html. Please see runTutorialOne.py (line 118) for an example: https://github.com/opensim-org/opensim- ... ne.py#L118

[Joel Quarnstrom]

Thank you for your help.

Another question, is the OpenSim scripting python code? Also, how do I create a loop that runs through the same code multiple times?

Thank you,
Joel Quarnstrom

[Thomas Uchida]

is the OpenSim scripting python code?

Please read the "Scripting" page in the Confluence documentation: https://simtk-confluence.stanford.edu:8 ... /Scripting

how do I create a loop that runs through the same code multiple times?

Please see the example scripts.

[Joel Quarnstrom]

Thank you, that documentation was helpful.

Also, do you know if it is possible for a script to open a macro enabled excel file and run a macro?

[Joel Quarnstrom]

Or is it possible for a c++ program to open OpenSim and run a script?