Hi to all, I still didn’t solve my problem with the WeldConstraint. I included the model and the movement (.trc file as well as the results from the inverse kinematics) so that you can see my problem – the WeldConstraint which should keep the two parts of the jaw together seems not to work :( . Than...

Hi Ana, I had an expression that when you define the .mot file with the external force (and torque) vector, you also define the point of application. Maybe I am wrong, but I expected the columns of the “force file” to be as Force Name_force_vx Name_force_vy Name_force_vz Point of application Name_fo...

Hi,
What exactly means tags <location_body_1> and <orientation_body_1> (and for the second body as well) ?

Michala

Hi to all. I am having problem with the introduction of the WeldConstraint to my model. As I described previously (https://simtk.org/forums/viewtopic.php?f=91&t=3636), my model consists of a fixed skull (upper jaw) and the movable mandible (lower jaw). These two parts I want to connect with two temp...

Hi,
I run the Analyze tool, since I am interested in the moments’ arms. And I am also wondering, where the results are saved? I got several .sto files (ActiveFibreForce, FiberForce, Force, Length, PennationAngle, etc.), but none is “MomentArm”. What am I doing wrong?

Michala

I have just found this post https://simtk.org/forums/viewtopic.php? ... +arm#p6200 so I will go through it and see if it helps.

Hi to everybody, Does the above mentioned project (OpenSim plugin to extract the muscle line of action) really compute the “moment arms” as well? I thought that it reports the “lines of action” and the “coordinates of the muscles attachments”. But not the moment arms, i.e. the distance from the musc...

Hi Chunxia, I have now similar problem as you had – I need to define a “reasonable but fake ground reaction force”. I, more or less, understand the structure of the file, but I am not sure how to insert/chose/calculate the “center of pressure” for my bony part (the _p vector). How did you define it ...

Thank you for the answer. I will try it. For now I have 4 DOF in each joint.

Michala

Hi William, I had a same error massage – in my case the problem was that I forgot to include the mass and inertial properties of individual body parts (bones). For the scaling and IK you don’t need those, so they run with no problem, but for the dynamics you need it. But as I saw in your .osim model...