Stress function based form-finding

I’m assuming people who love Kangaroo or RhinoVault once heard a rumor/myth about Airy stress function. I think there are no plug-ins/Grasshopper components available at this moment
Sorry, it is not a plug-in yet, but I am creating a simple Grasshopper definition (attached below) that computes a form in equilibrium using an Airy stress polyhedron and seeking a possibility to release it as a form of a plug-in. This is a spin-off from my research. Research is research, the code I wrote for the research is over 6000 lines and it is not for everybody’s use.
But, on another hand, this Grasshopper definition I am creating is a lot simpler, almost as minimum as possible, and does not require any external library.
I’m posting this to see if there is a demand, and also if the script is simple enough that this forum’s users can figure out how to use it. I’m also open to any type of feedback/requests.

PS. Please move this thread to the right place if I’m not posting to the right place.

What should pop up on your computer screen.

Grasshopper definition


[02/23/2021]**The attached file below has been updated so that the external library dependencies are fully removed.
flower - fdm -polyhedral (57.5 KB)


Hi @mikity_kogekoge

Thank you for sharing this!

The possibility of form-finding mixed compression/tension shells is exciting.

Adding a link here to your paper:

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Yes thanks for sharing this. Really interesting research!

Considering the dependencies and content I updated the category to #grasshopper-developer :slight_smile:

Update: I’m getting the expected results:

But am also getting the following dependency warnings when opening the file:

2021-02-23 11_11_24-Assembly Reference could not be resolved

2021-02-23 11_11_33-Assembly Reference could not be resolved

And am not seeing any reference to these in the C# script (and it executes without warnings):

Ya, I forgot to remove the links to the DLLs.
Here is a corrected one. (I also replaced the file in the original post)
flower - fdm -polyhedral (57.5 KB)

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Thanks Daniel!

This is what happens when tension and compression are mixed in general.
Once tension and compression are mixed, it is very hard to predict/control the shape.
(this animation changes the red lines from compression to tension (the rests are in compression))

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For the mixed type shells found with this tool am I right in thinking you would generally need internal tension cables/reinforcement, not just at the boundary?

Could you even turn them into structures of just masonry and cables like Block/Rippmann’s funicular funnel shells, but with internal cables following principal tension directions?

Hi Daniel, Philippe/Rippmann’s funnel shell has a tension ring on the perimeter. This one has tension forces in the internal area meaning if it is realized with materials with no capacity of tension (concrete/bricks/stones), then you need reinforcement bars/tension cables. But the location and directions are already known (cool!)

And if it is realized by steel plate (don’t ask how to bend) or by a grid shell, the tension/compression forces will appear just as designed in the tool. (this is also an amazing moment, just plug in the geometry to Karamba and you will see almost the same stress distribution specified by the tool)