Dodecahedral Shape-shifter

Show us your models and discuss model-making techniques. Paper? Wood? Single vs double tabs? etc.
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robertw
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Dodecahedral Shape-shifter

Post by robertw » Sat Apr 04, 2009 1:35 pm

Hey,

I just uploaded photos of a new shape I made. This one is flexible! It can transform between a regular dodecahedron and a rhombic dodecahedron.

Image
http://www.software3d.com/DodMorph.php

There's even a YouTube video of it in action :)

Rob.

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oxenholme
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Post by oxenholme » Wed May 13, 2009 7:29 am

I'm lousy at mathematics, but does this imply that the volume of a regular dodecahedron is twice the cube of tau (1.6180339etc) times its edge length?

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robertw
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Post by robertw » Wed May 13, 2009 9:30 am

No, because when in rhombic dodecahedral form, there are some gaps inside (although the orange parts do fold flat against each other).

However it is true of the rhombic dodecahedron, that it has twice the volume of a cube whose edge is the length of one of the rhombus's short diagonals.

Rob.

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