How to use Plasticity in Kangaroo when using the Beam function

Grasshopper Kangaroo
1

Hi everyone,

This is a similar question to For now, is it possible to introduce plasticity into the beam elements?. Is there a way to create plasticity for beam elements in kangaroo?

Thanks!

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Hi @Daniel_Z and @w.wu,
Sorry for not replying yet to the earlier thread.
There’s nothing in there for this right now, but I have been working on something that might be usable for this.

One new goal I have is to keep a pair of 6dof particles in the same location, and resist relative changes in orientation, but with a plastic angle threshold beyond which this rest relative orientation changes.

It might work to make the coincident end frames of consecutive beam segments separate, but connect them with this new plastic orientation goal.
This will only make the bending and twisting plastic though. The length will stay purely elastic, but I could make a new version where the rest length also changes if that’s what you are after?

It’s tricky to talk about clearly without a concrete example though. Do either of you have an example of the kind of use case you have in mind for this?
Thanks.

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Hi Daniel,

Thank you so much for your kind reply. Yes, the plasticiy you descripted (bending and twisting plastic) is exactly what we want now.

Here is the example you provided to us, and I added the anchor to one curve end. Could you please try this example? Say, if I drag the other end to change the curvature to a limit (i.e., bending the curve) then release, the curve can’t go back to its original shape because of the plasticiy. Let us know if this example is enough or not.

beam_hook2-waitingforplasticity.gh (26.4 KB)

Thank you so much again!!

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Okay, here’s a go at this:
beam_hook2plasticity.gh (21.0 KB)

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That’s a fantastic work!
I need more time to test and understand it.
Thank you again, Daniel!

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Happy to help.
I’m curious, what kind of project is this for?

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Hi Daniel, the project is for the simulation of cardiovascular stent expansion, which now only can be done by FEA simulations. If Kangaroo can do this work similiarly (of course not accurate as FEA simulation, but much faster), it will be a huge step forward.

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