I think converting body mass to weight first so that it's in units of N is correct. I also think that while calculating the residual forces as a percent of body weight makes sense. Percent body weight makes a little less sense with residual moments since the units aren't the same, but on the whole s...

I believe that is referring to the peak joint torques for the motion (such as the output when you run inverse dynamics) rather than the peak joint torque of the model.

Yes, in general you want to have reserve actuators' optimal forces to be small. One other reason for this is how the static optimization problem is posed. If the optimal forces of the reserve actuators are high, then it's "cheap" to use in the cost function of static optimization. Thus, they should ...

Trying to predict how the GRF changes due to an external perturbation is really difficult. You're taking a very interesting approach, but as you see this leads to some big residuals because it's hard to know how to change the COP. You might be able to do some of this through trial-and-error or tryin...

No worries at all, I don't know where this would be in the documentation. Overall, you're correct. Depending on the type of each individual joint in the model, inverse dynamics will return a moment or force, or both for each joint. And as you noted, if the coordinate related to a joint is rotational...

Unfortunately, I think the provided classes in OpenSim don't give a clear way to implement your problem using MATLAB. Creating a class to do this in C++ would likely work but may not be trivial to do. I wonder if there could be a way around this by implementing your equations in MATLAB. Depending on...

I can't think of any way to easily do this off the top of my head. One possible way to work around this would be to use the Analyze tool with a PointKinematics analysis where you specific points that coincide with the markers of interest.

I looked through the TugOfWar code from 4.1, and I see the controls section between L260 and L275. It looks like it's also using a PrescribedController as you are using with a linear function. Is this what you're referring to? If so, I think it should be doable. LinearFunction should be available in...

There are a lot of steps between the input data and getting out joint reaction loads which can make it difficult to find where an issue could be. We usually suggest breaking down the problem into the individual steps along the pipeline to isolate the problem. For instance: 1. How are the errors afte...

IAA documentation can be found at https://simtk-confluence.stanford.edu/d ... n+Analysis with an example setup file.

It may also be helpful to see other projects that have used IAA, such as https://simtk.org/projects/nmbl_running/