Where to see joint contact force?
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ajinkya patil
- Posts: 33
- Joined: Wed Jun 10, 2015 11:09 pm
Where to see joint contact force?
After running inverse dynamics tool I can only plot joint moments? How to obtain joint contact force e.g. Knee joint force etc.?
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Ross Miller
- Posts: 375
- Joined: Tue Sep 22, 2009 2:02 pm
Re: Where to see joint contact force?
Hi Ajinkya,
The output STO file that the inverse dynamics analysis produces should have variables in it called the "net joint force" (or something similar to that).
Note that this force is probably not the joint contact force (i.e. the force due to contact between the joint surfaces), unless your model has no muscles. If the model has muscles, you would need to run an analysis that calculates muscle forces (e.g. static optimization), then calculate the contact force using those muscle forces.
It's a bit dated now, but the review by Crowninshield and Brand (http://www.ncbi.nlm.nih.gov/pubmed/6749521) is a good summary of this topic, or maybe the more recent Erdemir review (http://www.ncbi.nlm.nih.gov/pubmed/17070969).
Hope this helps,
Ross
The output STO file that the inverse dynamics analysis produces should have variables in it called the "net joint force" (or something similar to that).
Note that this force is probably not the joint contact force (i.e. the force due to contact between the joint surfaces), unless your model has no muscles. If the model has muscles, you would need to run an analysis that calculates muscle forces (e.g. static optimization), then calculate the contact force using those muscle forces.
It's a bit dated now, but the review by Crowninshield and Brand (http://www.ncbi.nlm.nih.gov/pubmed/6749521) is a good summary of this topic, or maybe the more recent Erdemir review (http://www.ncbi.nlm.nih.gov/pubmed/17070969).
Hope this helps,
Ross