How to set the contact force of lumbar facet joint?

Main Forum
1

Hi Anybody,
I'm currently studying the model of "SpineFixationWithForceDepKinematics"(AMMR2.4.2).I want to output the contact force of facetjoint, but such an error occurs

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I don't know how to modify it to output the result.
Look forward to your reply，
Liu.

2

Hi Liu,

That is strange. I believe something has been modified in your code. I can't replicate this error. The model loads fine for me.

Can you try to install the AMMR again?

Best regards,
Dave

3

Hi Dave,
I reinstall the AMMR. And I want to output the force of the facetjoint during movement. So I changed the code from "NormedMeasureOnOff = Off;" to "NormedMeasureOnOff = On;" in the "FacetContForces" file，and load the Model. Error still occur.

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Will your model experience the same issue in this situation？ Is this an error code in code programming？ Can I obtain the force of facetjoint through other methods?

Thanks in advance!
Liu

4

Hi Liu,

I understand now.

Yes, if you set NormedMeasureOnOff = On; the code will break. This is because it will combine the output from AnyKinPointSurface to a single value.

You can find the facet joint force in the code that follows: ContactForcesR.F, for example. These will be expressed in each measure of the PointSurface measure.

You can also see the Force value in the Global system in RefFrameOutput.F

Best regards
Dave