Hello Mike, These are mostly from practical experience. This is a more official source with additional information: http://simtk-confluence.stanford.edu:8080/display/OpenSim/Modeling+and+Simulation+Best+Practices This reply is very late because several of us who monitor this page got caught up in gr...

Hi Hassan,

I wrote up some examples of how to run a batch of IK (or any other tool) using setup files and matlab here:
http://wiki.simtk.org/modelerskitchen/S ... processing

-Edith

Hi Jae, The best source for the theory behind the Schutte muscle model is Lisa Schutte's dissertation, appendices 2 and 3. Using musculoskeletal models to explore strategies for improving performance in electrical stimulation-induced leg cycle ergometry LM Schutte - 1992 - Stanford University Accord...

A hacky way to do this would be to place a marker at the joint centers, create a "Measurement" in the scale tool between these markers, then apply manual scaling to change the segment length the desired amount. I've done this when I have functional joint center measurements at the hip by placing a m...

Hi guys, This explanation of solving for equilibrium states is not quite correct. There are two different types of equilibrium being discussed here and there is ambiguity in the tag name that obfuscates the issue a bit. Type 1: The muscle and tendon are in equilibrium such that (Muscle active force ...

Hi Ruoli, I don't think this is what is affecting your compute time. This message appears in patlig because that muscle's FMax is 0 (it's a hack from when there weren't ligaments in OpenSim). It's true that there's a small force and that's appropriate. I'm not sure why it's appearing in pectineus, e...

Hi, Yes, max_isometric_force is the parameter that people are referring to when they say to change muscle strength. Generally, unless there is reason to believe that the subject you are modeling has an atypical force distribution, I think it is best practice to increase all the muscle forces by the ...

Two bugs in the 2-leg, OpenSim version of the lower limb model were recently brought to my attention, and I have posted a new version to correct these issues. v2.1 is now available for download. The bugs and fixes are: Bug: The range of the knee_angle_r and knee_angle_l coordinate was inappropriatel...

I have added an example of how to do batch processing of open sim tools in matlab to the downloads section. Please let me know if you have any questions or suggestions.

<t>Hi Shiuan-Lin,<br/> Taking a subject's joint moment data with a dynamometer and adjusting the model's Fmax values would be a good way to validate a model if you want to argue that it is subject specific, but I think most people do not take this step. Rather, they follow a procedure more like the ...