Search found 375 matches

by Ross Miller
Wed Jul 25, 2012 12:07 pm
Forum: OpenSim
Topic: Asymmetry in states of symmetric two-legged model
Replies: 5
Views: 816

Re: Asymmetry in states of symmetric two-legged model

Hi Ayman, That makes sense re: constraint tolerances, etc. It is indeed a MovingPathPoint, but both the splines defining its position as a function of the coordinate value (the knee angle, in this case) are also different, along with the positions specified in the <location> tag. The <x> values for ...
by Ross Miller
Wed Jul 25, 2012 9:59 am
Forum: OpenSim
Topic: Asymmetry in states of symmetric two-legged model
Replies: 5
Views: 816

Re: Asymmetry in states of symmetric two-legged model

Hi Ayman, It looks like all the definitions are completely symmetric in the model now (the one I'm using), but I still get some small asymmetries. They are functionally pretty meaningless (like a few hundredths of a degree at most). I'm not sure why. I have all the non-saggital DOF locked but the gr...
by Ross Miller
Wed Jul 25, 2012 8:49 am
Forum: OpenSim
Topic: plotting length
Replies: 2
Views: 404

Re: plotting length

Hi Caterina, I'm not sure how to plot ligament object lengths exactly, but if the ligament length is not showing up as a plotting choice, you could create a new muscle model that has the same coordinates as the ligament, and zero out its active and passive force properties. Then you can plot it as y...
by Ross Miller
Tue Jul 24, 2012 3:02 pm
Forum: OpenSim
Topic: Asymmetry in states of symmetric two-legged model
Replies: 5
Views: 816

Re: Asymmetry in states of symmetric two-legged model

Found it, the muscles weren't actually symmetric. It looks like there's a discrepancy in the 4th path coordinates on the left and right side for the vastus intermedius (aside from the flipping of the z-coordinate). Here's for vas_int_r: <location> 0.05546322 0.02529232 0.00180000 </location> and for...
by Ross Miller
Tue Jul 24, 2012 11:49 am
Forum: OpenSim
Topic: Asymmetry in states of symmetric two-legged model
Replies: 5
Views: 816

Asymmetry in states of symmetric two-legged model

Hi all, I'm working with a two legged model (a modified version of the Hamner full-body model). The model definition appears to be bilaterally symmetric in both the skeleton and the muscles (i.e. the left leg is a mirrored copy of the right leg). However, when I run forward simulations with the mode...