Hi team,
Thank you very much for giving us all access to such an incredible model. I am a final year biomedical engineering student at Imperial College London, and I am trying to use this model to calculate muscle forces from experimental data. I am new to OpenSim and apologise if this is rather basic, however I would love to add muscle forces to the arms of the model as well as additional markers to match the ones that were experimentally taken. I was wondering how this would be possible and any guidance would be heavily appreciated! Thank you in advance for taking the time to read this and for any additional help offered.
Best regards,
Kenneth Panteleev
Biomedical Engineering MEng candidate
Imperial College London
Adding Arm Muscles
- Jacob J. Banks
- Posts: 97
- Joined: Tue Jul 15, 2014 5:17 am
Re: Adding Arm Muscles
Ken,
Thanks for your kind words and interest in our model.
Unfortunately, we don't have an 'easy' solution for you... if we did, we would have added the arm muscles already! That said, it isn't an insurmountable task. One would just do what we did with the lower limb... find an applicable OpenSim Upper Arm model and CAREFULLY add the muscles (and maybe some DoF). Burkhart et al. 2020 touches on how this was done (in brief you just modify the .osim text file to include the muscles you want):
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8383199/
You would then want to validate the model too.
We haven't been overly concerned about arm muscles in the past because their impact on spine loading is probably minimal. That, and the shoulder is incredibly complex. We already have the lats crossing the shoulder. The lower limb was of interest because of the psoas crossing the hip and it's interaction with lumbar loading during gait.
Another solution could be to use our current model, then extract the kinematics and appropriate external forces and apply them to an upper extremity model.
Hope this sort of helps. Otherwise, happy to chat more (but would want to know more about the tasks you are trying to model and why the arm forces are of interest).
Jake Banks
Thanks for your kind words and interest in our model.
Unfortunately, we don't have an 'easy' solution for you... if we did, we would have added the arm muscles already! That said, it isn't an insurmountable task. One would just do what we did with the lower limb... find an applicable OpenSim Upper Arm model and CAREFULLY add the muscles (and maybe some DoF). Burkhart et al. 2020 touches on how this was done (in brief you just modify the .osim text file to include the muscles you want):
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8383199/
You would then want to validate the model too.
We haven't been overly concerned about arm muscles in the past because their impact on spine loading is probably minimal. That, and the shoulder is incredibly complex. We already have the lats crossing the shoulder. The lower limb was of interest because of the psoas crossing the hip and it's interaction with lumbar loading during gait.
Another solution could be to use our current model, then extract the kinematics and appropriate external forces and apply them to an upper extremity model.
Hope this sort of helps. Otherwise, happy to chat more (but would want to know more about the tasks you are trying to model and why the arm forces are of interest).
Jake Banks
- Kenneth Panteleev
- Posts: 2
- Joined: Mon Oct 17, 2022 9:17 am
Re: Adding Arm Muscles
Hi Jake,
Thank you very much for an incredibly prompt and insightful response. I will read through the paper and try to find other upper extremity models to add to the spine model.
The overall aim of my project is to quantify muscle fatigue and stability in archers. Specifically, comparing the differences in muscle forces between the two. I have experimental data, obtained through optical markers, for a novice and experienced archer and I plan to apply inverse kinematics through OpenSim, to compute the muscles forces during the motions.
It is theorised that elite-level archers experience less muscle fatigue due to the technique of their shot (they engage their shoulder and back muscles more than their biceps, the reverse is true for novice archers). I hope that through this model, this will be confirmed!
Thank you again for your advice and help! I shall be in touch again if I stumble on some hurdles!
All the best,
Kenny
Thank you very much for an incredibly prompt and insightful response. I will read through the paper and try to find other upper extremity models to add to the spine model.
The overall aim of my project is to quantify muscle fatigue and stability in archers. Specifically, comparing the differences in muscle forces between the two. I have experimental data, obtained through optical markers, for a novice and experienced archer and I plan to apply inverse kinematics through OpenSim, to compute the muscles forces during the motions.
It is theorised that elite-level archers experience less muscle fatigue due to the technique of their shot (they engage their shoulder and back muscles more than their biceps, the reverse is true for novice archers). I hope that through this model, this will be confirmed!
Thank you again for your advice and help! I shall be in touch again if I stumble on some hurdles!
All the best,
Kenny