MPC Joints Shared Between Bodies

MR
Matthew Ridzon
Wed, Apr 24, 2024 9:07 PM

Folks,

I'm in Workbench and have built a truss structure from line bodies.  The assembly has some shells as well.  I have nearly 50 MPC joints tying everything together.  About two dozen of those joints output bogus force reactions when I probe their results.  I receive the following warning during solution...

"Two or more remote boundary conditions are sharing a common face, edge, or vertex.  This behavior can cause solver overconstraint and is not recommended, please check results carefully.  You may select the offending object and/or geometry via RMB on this warning in the Messages window."

I believe the entangled MPC joints is the crux of my issue, since they are sharing edges, vertices, and faces, but I don't know how to fix it without deviating from reality.  I have the members tied together to emulate reality so it's not like I can just delete various joints and still be accurate.

I would share an archive or some screenshots, but I don't think this email system handles big emails like that.  So in the absence of that, I'm looking for any tips you can share that I should consider.

Matt Ridzon, PE, MSME
Sr. Engineering Analyst

Email    matt@prime-engineer.commailto:matt@prime-engineer.com
Mail        266 Main St, Burlington, VT 05401
Web      www.prime-engineer.comhttp://www.prime-engineer.com/
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PRIME ENGINEERING LLC

This message (including any attachments) may contain confidential, proprietary, privileged and/or private information. The information is intended to be for the use of the individual or entity designated above. If you are not the intended recipient of this message, please notify the sender immediately, and delete the message and any attachments. Any disclosure, reproduction, distribution or other use of this message or any attachments by an individual or entity other than the intended recipient is prohibited.

Folks, I'm in Workbench and have built a truss structure from line bodies. The assembly has some shells as well. I have nearly 50 MPC joints tying everything together. About two dozen of those joints output bogus force reactions when I probe their results. I receive the following warning during solution... "Two or more remote boundary conditions are sharing a common face, edge, or vertex. This behavior can cause solver overconstraint and is not recommended, please check results carefully. You may select the offending object and/or geometry via RMB on this warning in the Messages window." I believe the entangled MPC joints is the crux of my issue, since they are sharing edges, vertices, and faces, but I don't know how to fix it without deviating from reality. I have the members tied together to emulate reality so it's not like I can just delete various joints and still be accurate. I would share an archive or some screenshots, but I don't think this email system handles big emails like that. So in the absence of that, I'm looking for any tips you can share that I should consider. Matt Ridzon, PE, MSME Sr. Engineering Analyst Email matt@prime-engineer.com<mailto:matt@prime-engineer.com> Mail 266 Main St, Burlington, VT 05401 Web www.prime-engineer.com<http://www.prime-engineer.com/> [A blue hexagon with white letters Description automatically generated] PRIME ENGINEERING LLC This message (including any attachments) may contain confidential, proprietary, privileged and/or private information. The information is intended to be for the use of the individual or entity designated above. If you are not the intended recipient of this message, please notify the sender immediately, and delete the message and any attachments. Any disclosure, reproduction, distribution or other use of this message or any attachments by an individual or entity other than the intended recipient is prohibited.