Model 2392 + Umberger 2010 Metabolic Probe

[Allison Porter]

I am trying to perform a metabolic analysis on the 2392 model both in unassisted walking and with a modeled knee exoskeleton (similarly to this example: simtk-confluence.stanford.edu:8443/display/OpenSim/Simulation-Based+Design+to+Reduce+Metabolic+Cost)

At the end of the opensim example, the instructions describe how to use the metabolic probe feature with the 2392 model. However, the probe does not seem to be working for me. I followed the following steps for the unassisted walking case:
1. Open the Gait2392 model in the OpenSim GUI (Models/Gait2392_Simbody/gait2392_simbody.osim).
2. Run the addMetabolicProbes.py script.
3. When prompted, select the file containing the slow-twitch ratios for the muscles in the model (metabolicsSlowTwitchRatios_Gait2392.txt).
4. I ensured in Navigator>Probes>Metabolics, the "enabled" box was checked.
5. Tools>CMC to run CMC

However, the example states that when you run CMC, a ProbeReporter analysis runs in the background and that if you go to Toos>Plot>Y-Quantity>load file, in the CMC results folder there should be a MetabolicsReporter_Probs.sto file. There is no such file for in this folder after I run CMC.

(note, when I ran CMC, I used the provided CMC setup file).

Any help troubleshooting this error would be appreciated.

[Thomas Uchida]

If you want CMC to report the values of the metabolic probes, you need to add a ProbeReporter. One way of doing this is to edit the CMC setup file (e.g., in Notepad) and add the probe under "AnalysisSet".

Code: Select all

<AnalysisSet name="Analyses">
  <objects>
  <ProbeReporter name="ProbeReporter">
    <!--Flag (true or false) specifying whether on. True by default.-->
    <on>true</on>
    <!--Start time.-->
    <start_time>0</start_time>
    <!--End time.-->
    <end_time>100</end_time>
    <!--Specifies how often to store results during a simulation. More specifically, the interval (a positive integer) specifies how many successful integration steps should be taken before results are recorded again.-->
    <step_interval>1</step_interval>
  </ProbeReporter>
  </objects>
  <groups />
</AnalysisSet>