Hello all,

I have the same problem as Yu-Wei, I can't open the website above. Actually, all "Documentation" website is inaccessible for me, but the "Topic" is fine. Interestingly, I could get access to "both" at home. It is really weird.

I just came into mind two possible reasons, one is the unit, the marker trajectory collected in Motion Analysis is in Unit mm, while OpenSim uses Unit m. The other one is misplacing of markers on the subject during motion capture. Might the above two cause the unreasonable results? Thank you.

Hi Kaewing, I actually have the same question. Recently I created a self-use markerset by adding several markers on the Gait2354 model (two are the R.PSIS and L.PSIS). I just give them a random location (-0.06 0.12 0.13, and -0.06 0.12 -0.13). After scaling, IK calculation, I got some weird results....

Hello Everyone, I am using OpenSim to calculation joint angles during gait. I define a markerset, scaled the model and do the IK calculation(see attachments). However, when I plot the results, I found unreasonable hip flexion (~25degrees) at neutral standing position where obviously it should be abo...

Dear Ayman, Thank you for viewing my email. I am a new user of OpenSim. Now I have a question during doing my work. I use the Gait2354 model, scaled it, and calculated the IK of one of my file (walking.trc), Actually, in this .trc file, certain marker (L.Acromium) is missing for the first frames (no...

Hey Miriam, I am a new user of OpenSim. I am kind of confused about some words. The virtual markers, are they those markers on the model (for example, on the sample model Gait2354), and the experimental markers are those what we used during the measurement with Motion tracking system, am I right? I ...

Hello Dear OpenSim community, I have solved the second problem after practicing with the tutorial and user guide. In terms of the first question, does anyone know the function of the markers attached to the thigh and shank ? I would be very delighted if anyone could post some suggestions. Thank you.

Hi Xiaoyan, I am having the same problem. Have you solved it? What marker set do you use in your experiment, and the values for scale factor and weights? Thank you! Hi james, Thank you for your help. Your detailed reply really helps me in understanding how to do model scaling and inverse kinematics ...

Hi Xiaoyan, I am having the same problem. Have you solved it? What marker set do you use in your experiment, and the values for scale factor and weights? Thank you! Hi james, Thank you for your help. Your detailed reply really helps me in understanding how to do model scaling and inverse kinematics ...

Hi James, Will a gap (missing marker in certain frame) in the .trc file produce the same problem ? I am a new user. I collect data using Cortex, and export .trc file. Should I fill the gaps for the motion data prior to OpenSim ? Does OpenSim has the gap-filling function? Thank you ! Abeer- Perhaps c...