We have recently gained access to our School's Linux based cluster, and we have gotten OpenSim (4.3) to work with Matlab (by 'we', I mean an outstanding IT person). While things 'work', we have noticed that there is a pretty significant memory leak when we use the Analysis Tool (and probably other t...

Good deal. Congrats and good luck!
I might have time to attend... if that is ok with the school etc. Probably better to email the link though, so it isn't on a forum:
jbanks3@bidmc.harvard.edu
If I can't make it, good luck again!
Jake Banks

Yup... see in columns B-M??? those moments/forces have nothing to 'help' them in SOpt, and they are not trivial. So it is good to set your reserve actuator torque/force (in the RA file) for those moments/forces to be at least as high as the max you expect (probably 2x). Try that (in SOpt). While you...

Can you attach the InvDyn results? In addition, try increasing the optimal force(s) for all board and pelvis related Reserve actuators to 500. See if SOpt solves then. I think it will. As even during 'normal' situations the pelvis actuators need to be >100, as they help adjust things relative to the...

Sorry, been busy/preoccupied. You set things up how I would have (at least initially), but I have think that how the board is part of the pelvis is messing things up. Run the InvDyn tool on it. Let's see what sort of moments are being generated on the pelvis by the board. If you don't know how to do...

Do you have reserve actuators on the board DoFs? I think you may need some and that is your constraint violation. Otherwise OpenSim can't justify having the board in a given position. I was recommending you take a single time InvKin and GRF frame (say time 0 /frame 1) and repeat that frame (manually...

I'd have to see the 'new model', but my initial guess is that you added a balancing board with a mass of 0. OpenSim does not like bodies with 0 masses (or moment of inertias with 0 masses), as hard to have in the denominator. If this is not the case, you could try solving for a few 'static' frames. ...

No problem. Are you not filtering the kinematics prior (at least a 6Hz cutoff)? If not, that could be it (IK needs smoothed otherwise too much acceleration), because some of those muscles shouldn't be maxing out. Otherwise, are your GRFs in the wrong units? Do you not have GRFs? Also, add reserve ac...

Oh, suppose I neglected to answer you time/speed question No, there is no real way to speed up, unless you have faster computer or write some MATLAB parfor code to try to distribute the processing. With >600 MTAs and a lot of DoF, it just takes a long time. In our experience, on a decent PC it takes...

What sort of movement are you modeling? Which muscles are maxing? Unfortunately, in our experience, it is not uncommon for the legs to limit some lifting movements. The leg MTAs are just based off from another OpenSim model (can't recall which), that has primarily been used for gait (so only previou...