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Here are my... things :o - Twisting pentagonal tubular frame

PostPosted: Tue Dec 01, 2020 12:48 am
by Eric
I was playing around with a pentagonal tubular frame, that is very interesting because it's rock solid (but so rods-consumming :o )
Some simple rules :
- pentagons must be reinforced by a pentagonal pyramid (or a pentagonal panel to spare rods)
- pentagonal pyramids can be turned inwards or outwards (concave or convex)
- leaning on a regular icosahedron or an outwards pentagonal pyramid allows you to change direction.
- a regular icosahedron can support up to 3 different pentagonal tubular frames in 3 different directions

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Baby snake

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Mother snake

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Ascending spiral unstable and too heavy not to be propped up

Re: Here are my ... my ... my things :o

PostPosted: Tue Dec 01, 2020 12:55 am
by Eric
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Ascending then descending spiral in the same movement.
Anyway, something colorful

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From a slightly higher point of view

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The same .. thing from above. Couldn't have guessed what it would be

Re: Here are my ... my ... my things :o

PostPosted: Tue Dec 01, 2020 1:00 am
by Eric
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An alien creature
It would be a lie to say it is very stable. it is barely at the point of equilibrium. An extra row of rods to the right side would not have been too much ;-)
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Or maybe a trophy or something?

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Nope a definitely terrifying alien thing

Re: Here are my ... my ... my things :o

PostPosted: Tue Dec 01, 2020 1:09 am
by Eric
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Alien Kiss!

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From above

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Almost symmetrical

I'm telling nonsense. Ok I'm leaving.
It's time to go to bed ...

Re: Here are my... things :o - Twisting pentagonal tubular f

PostPosted: Sun Feb 26, 2023 6:28 pm
by Wagyx
Hey there,
technically speaking, any such shape can be decomposed into:
- Pentagonal antiprism for the tube part
- J62 Metabidiminished Icosahedron as a joint for changing directions
- J63 Tridiminished Icosahedron as a joint for connecting three tubes together
- J2 Pentagonal Pyramid for end caps

Mathematically speaking, I see connecting two shape together face by face as adding (or augmenting in Stella's vocabulary) and extruding one shape from another (like with J2 and any other one) as subtracting or excavating (Stella still).

It make an algorithm for the generation of such tubular shapes much easier to envision.
Of course, other shapes with pentagons could be used too, like the dodecahedron or the pentagonal prism, I guess they would disrupt the intent behind the twisting tubular frame though.