Designing Beams in Karamba for Optimization

Dear experts,
First of all, thank you for the usual very fast and efficient replies, your help is really appreciated.

I have been trying to optimize cross sections of fabric-formed beams using Karamba. While the design of the beam is slightly complicated, I have not yet seen a way to define an organic shape as a beam in Karamba to do the study or optimization.
Is there a way to define these shapes as a beam to be analyzed in Karamba?

Note: I don’t think that uploading an example can help but I can upload one if necessary. Also, I have the full version of Karamba, not that it would make a difference but just as a note.

Thanks in advance.
Kal.

Hi Kal,

it is not possible to define unique cross sections directly in Karamba3D. However if you have unique cross sections, you can use the Modify Cross Sections component to set the properties of your cross section - please refer to Angular cross-sections in Karamba?. The profile of the cross section will not be shown in the Beam View.

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Dear Mathew,
Thank you for the kind reply,

I understand that there is an option of setting the properties of a certain cross-section for a beam in Karamba, but would that work for setting different cross-sections at different points in the same beam?
This way, the beam would have determined cross-sections on multiple points along the beam, which would be exactly what i want for the optimization.
Thank you again.

Kal,

I figure it out that you´ve already checked the manual, but in fig. 3.3.1 a beam with multiple cross-sections is illustrated: https://manual.karamba3d.com/3-in-depth-component-reference/3.3-cross-section
It seems that you can merge as many cross-sections as line segments to obtain the corresponding beam segments with the desired cross-sections. I hope this helps!
PS: I haven´t verified this, eventually, would you confirm it works? Thanks!

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Yes that is correct. You can also refer to this example - https://www.karamba3d.com/examples/simple/single-span-beam/ where the beam is split into segments where you can apply multiple cross sections.

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Dear Vigardo and Mathew,
Your help really helped on many levels, thank you!

I followed the manual in trying to create a beam with multiple cross sections, it worked in model view but for some reason before analyzing the model when it enters “optiCroSec” it would eventually use one of the cross sections only, I might have a problem with that myself since my experience with Karamba is still shallow.
In addition, I also figured out that it would be easier to change my topic of research into shells instead of beams since even if I was able to fix this for now, the final shape of a designed beam with organic shapes would be a bit more complicated than choosing multiple cross sections ;which I’m suffering with now already!
I attached a copy of the gh file if you would want to check the outcome of choosing different cross sections with a picture of an example I was hoping to achieve using the definition.
If you have any further advice, I would gladly listen and try.
Thank you so much !

Kal.!
3-Figure4-1|690x244 04.gh (49.5 KB)

Hi, I know this is an old thread, but I’m running into the same issue. For me, merging the cross sections doesn’t obtain corresponding beam segments when the model is analyzed. Is there something that I’m missing?
cross sections.gh (45.1 KB)

Hi Karamba3D follows the longest list principle of Grasshopper. You only have one beam but 2 cross sections, so it will only take the first cross section in the list. If you want both cross sections to be defined in your beam then you need to split your beam into two separate elements.

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Thanks!