A sequence of 4 models which are stages in a continuous transformation of a structure.
In a physical form, this consists of 8 equilateral triangles, connected at vertices by linkage
that allows movement. In this model, the yellow and purple triangles are rigid, while the
green surfaces can be seen as open. The yellow triangles rotate in one direction, while the
purple triangles simultaneously rotate the other way. Rotatinng the yellows clockwise and
the purples counterclockwise, the octahedron transforms into an irregular icosahedron,
then to a cuboctahedron, then to a regular icosahedron, and back to an octahedron.
Buckminster Fuller called this transformable structure a jitterbug.