Why is my RBD sim acting strangely?

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Hi,

I have a very strange thing happening, and I'm guessing it has to do with my glue network and active/passive logic, but I'm not able to figure it out.

I have a box that I fractured as a ‘sinkhole’ and I used a glue network and active/passive logic to control where and when things were fractured.

I also set up a ‘cluster’ attribute using color so that the glue network would ‘stick’ together at certain points.

However, some of my fractured pieces start to fall, and then stop falling. It's very strange.

Any help would be appreciated.

Thanks,

Jim

Attachments:
sinkholeSandTest_v001.hiplc (409.7 KB)

Reel Inpsirations
Houdini Work in Progress [vimeo.com]
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Your set up seems to me a bit chaotic. It may be better to simply specify the islands of glued fracture pieces and just animate the pieces activation. I justset up a quick such scene in the sample file I gave you.
But I have to warn you, this depends on how realistic the breack you need it to be.
As even with this solution you will have the problem that the island will not fall naturally, as it will only fall once the entire pieces are active.

Attachments:
prefractureActivationwithglue.hiplc (316.6 KB)

https://www.imdb.com/name/nm8408875/ [www.imdb.com]
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Thanks Nicolas,

Definitely a different setup for sure.

My setup is based on this tutorial: http://www.digitaltutors.com/tutorial/1091-Controlling-Your-Fractures-in-Houdini#overview [digitaltutors.com]

Also, I'm going to be using this setup on a larger scale so I want to be able to deal with Packed Prims.

Realism is what I'm after as well.
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Houdini Work in Progress [vimeo.com]
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My set up can be easily adapted to use packed objects, I included here the same scene adapted to packed objects.
My idea is that rather than driving the simulation by erasing the glue network and keeping glue island you can just define the glue island and activate the pieces that you want them to start falling.

Attachments:
prefractureActivationwithgluepacked.hiplc (345.7 KB)

https://www.imdb.com/name/nm8408875/ [www.imdb.com]
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