This is a placeholder article for a diversion I went down today. --Karl Horton 10:43, 30 April 2007 (UTC)
There's a French architect called Alain Lobel who has spent more than a decade studying and cataloging the ways that a flexibly connected net of equilateral triangles can be used to build practical structures.
I came across him because a guest left a comment on one of Rodrigo's (rveas) structures over on flickr.
Hey, we have a way of building just such a flexible net of triangles, don't we?
Lobel's web site is at: http://www.equilatere.net and the text is in French and English.
At first I didn't believe that these structures would work: they appear preposterously flimsy, but I now think I'm wrong.
Today I built one of the dimpled C6's as a dome, and built a fully enclosed plio.rayf.rivf.60N60P4.C6 link which, incredibly, is rigid.
I'll try to help your intuition out here: as you probably know if you build a "fishing net" made out of just trianges, it is a flimsy affair. You can pick it up, and drape it over your arm, but it's so obviously unstable that when you look at the architect's diagrams of a Lobel net you assume that its stability must come from some external support.
The 'trick' is in the subtle way that the positively and negatively curved vertices nestle together: think of an egg box.
I predict that Rodrigo is going to be pretty excited about these structures: I haven't yet tried any big nets ....
Pictures to follow.