Origami: wobbly cube

Wobbly cube

Wobbly Cube, a one-shot design by me

This was one of my experiments in curved creases.  I basically cut out 12 identical S-shaped strips (with ruler and compass), and then creased them along their centers.  Then I quickly invented a scheme for secure attachment.  Not much more to say about that.  I like how it turned out.

Origami: Octopus 2

Octopus, by Sipho Mabona.

Back in 2016, I made an octopus and posted it here on A Trivial Knot.  Now I’m showing my second attempt, which was made two years later.  With more experience, I was able to make a more elegant octopus, while also using foil paper (which is generally harder to work with).  I was quite satisfied.

Although… if I want to pander to a certain someone maybe I ought to switch to spiders.

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Origami: Six intersecting pentagonal prisms

Six intersecting pentagonal prisms

Six intersecting pentagonal prisms, designed by me.

I might be less active this month, so I thought I’d make up for it with an origami model you can dig into.  This model is called “Six Intersecting Pentagonal Prisms” because it’s literally made from six pentagonal prisms.  I’ve got some photos below the fold showing the step by step addition of each pentagonal prism.

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On color theory

This is a repost of an article I published on Tumblr in 2017.  As many things I publish there, it was written somewhat extemporaneously, but it stood out as something I wanted to eventually import here.

There are really two color theories, the scientific theory of color perception, and the aesthetic theory of choosing color palettes.

The former is quite interesting, containing some surprising facts: yellow is the brightest color, many shades of green can’t be produced by modern displays, white is defined arbitrarily.

The latter is a hodgepodge of various historical ideas and a collection of overgeneralized advice. When I’ve read about aesthetic color theory online my impression is that much of it is either already taught to children or else it is not very good. Here is my attempt to identify some non-bullshit principles of color theory.

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Origami: Skarmory

Skarmory, designed by Shintaro Miyamoto

I dabble in many kinds of origami, especially in the context of interacting with origami groups.  I created this model, because someone at the origami group was really excited about making Pokemon, and asked if anyone could help him with this one.  It was difficult because we didn’t know the folding steps, we only had a crease pattern.

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Origami: Truncated octahedron

truncated octahedron

Truncated Octahedron, designed by me.  I kept this on my office desk.

Today’s model is one of my earliest original designs.   This is a truncated octahedron, which is the shape you get when you take an octahedron, and chop off the 6 tips.

I was interested in designing a model with this particular shape, because it has some special significance in condensed matter physics.  There’s a certain kind of crystal structure, called the “body-centered cubic structure”, which looks like this:

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Origami: Double-pointed VWXYZ Squares

VWXYZ variation

Double-pointed VWXYZ squares, a design by me

Ah, so here’s a really old original design that I made in 2013.  The story goes that I have a copy of Meenakshi Mukerji’s Ornamental Origami, which has a chapter on planar models.  These are models where the folded form consists of multiple intersecting planes.  One of my favorite models of all time is Tung Ken Lam’s WXYZ Triangles, which consists of four intersecting triangles.  Later origamists would take this idea even further.  What if you had 5 intersecting planes, or 6 intersecting planes, or more?  So I made a bunch of planar models with different numbers of planes.

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