RRA doubts and validation

[Vishal R]

Dear OpenSim team,

I have been doing RRA for level ground walking on 2392 musculoskeletal model and I have a few questions on how accurate it is. I have read the RRA troubleshooting tips as mentioned in http://simtk-confluence.stanford.edu:80 ... +Practices. Please find the video of my simulation here https://www.youtube.com/watch?v=iRF8htvZq5I

And the results are:

Code: Select all

************************************************************
*                   Final Average Residuals                *
************************************************************
* After pelvis COM and Kinematics adjustments:
*  FX=16.2399 FY=-0.693978 FZ=-3.31446
*  MX=2.54391 MY=-6.48655 MZ=13.7256
************************************************************

I have edited the FX,FY,FZ, MX,MY and MZ with an optimal force as 3,41,3,3,6 and 3 respectively. I chose this value after a lot of iterations and visually checking the simulation. Also I have made the changes (like changing the point of action, center of mass from the pelvis of the body) as mentioned in the troubleshooting tips.

A small drop and slight drift can be noticed in the model. Is this OK? I would like to know if these results are good so that I can proceed with further analysis. Also, what other changes can be made to improve the results?

Thanks a lot for your valuable feedback,
Vishal

[jimmy d]

You have not accounted for all the external forces. You start RRA when the right leg is in stance, but you do not have external forces for it.