The updated model notes how multifidus muscles were added to the model, and I am curious where the parameters for this model came from. Several of them have tendon slack lengths that are longer than the muscle tendon length in the neutral position. Doesn't this mean that these muscles cannot generat...

Hi everyone, I am creating a dynamic head and neck model. When I run static optimization, it solves with no problems. However, when I run CMC I get this error: CMC.computeControls: ERROR- Optimizer could not find a solution. Unable to find a feasible solution at time = 1.88833. Model cannot generate...

Hi everyone, I'm trying to understand how joints are stabilized from activation of opposing muscle groups. So far, my understanding is that muscles get stiffer when they are subject to higher activation levels. This muscle stiffness generates joint stiffness even when opposing muscles cancel each ot...

The problem was with my graphics card. I simply had to adjust my graphics card setting to use my graphics card for opensim instead of the integrated card.

Thanks for your help.

What exactly am I supposed to change in the opensim.conf file? I don't see anything about available memory in that file. It looks like it happens more in models that have more bodies. Any models from the examples that have the torso/head has a significant delay. The leg6Dof9Musc model has less of a ...

I just installed opensim on a new laptop to use along side my desktop. Everything seems to be working fine, except that there is a delay when I rotate the model by clicking and dragging. When I click and drag, there is about one second of delay until the model starts rotating. Once the model rotates...

I am analyzing motions of the head and neck. I have found the head to be very unstable without some element of stiffness and damping, so I added the SpringGeneralizedForce. I have the residual actuators there to make sure that static optimization or CMC will actually solve. The problem is that the r...

Is there a way to do this just by editing the xml file? I would like to add it straight into my model and run it in the GUI.

Hi everyone, I am having a problem with the ExpressionBasedCoordinateForce. When I try to add it to my model.osim file I get the error: 'ExpressionBasedCoordinateForce' is not a registered Object! Object type ExpressionBasedCoordinateForce not recognized Is this object no longer working for OpenSim?...

Any help?