Hello, I do not understand the output I am getting from Inverse Dynamics. As an example, attached is a plot of hip_flexion_r_moment that I get from ID run on Sam Hamner's Subject 17 at 5 m/s. It has a -5600 Nm dip at .35 seconds. It looks nothing like the usual hip flexion moment. Am I misunderstand...

Hello Ayman, Ajay and all, I would like to do the following simulation of slow knee extension from 90 to 0 degrees. This is a series of static calculations--I am not interested in acceleration. Pose the human model as if sitting, femur horizontal, leg hanging down in static equilibrium, i.e. knee an...

Thanks again.
Here is the matlab file I used to pad with zeros. Cheers,
John

Yes, Thanks Ayman,
There were blanks instead of zeros in the data file--this can be seen by comparing my data to good data in excel.
I replaced blanks with zeros with the attached matlab script and now the forces look good.
Cheers,
John

The grf file in my previous post has a problem. Here is the original:

Here are the other files: Here are screen shots of what I am doing. The green GRF arrow appears, but it is not moving.
John

Thanks Ayman, I understand what you are saying, but I am having trouble doing it. I would like to view ground reaction forces (file transformed_comfortable3_grf.mot too large to Attach) synchronized with IK results: subjectB_comfortable3_ik.mot according to load specification: externalLoadSpec.xml I...

Hi Ayman and all, I have a similar problem. I have run inverse kinematics, and now I need inverse dynamics. When I preview the grf.mot file, all I see is the yellow-red-green axis system. 1. How can I visualize the forces? 2. the marker motion data .trc file and the grf.mot files have different data...

The user manual has an explanation in the scaling chapter:
http://simtk-confluence.stanford.edu:80 ... Scale+Tool

Regards,
John

Hi Ayman and all, I am having trouble with scaling and previewing data. When I try File > Preview Motion Data... an Unexpected Exception occurs in OpenSim (red circle in lower right of GUI window) OpenSim version is 3.0 I have "3D Gait Model with Simple Arms" open first. Attached is the static pose ...