This is about transformation of tetrahedra. Edges are rotated about a line between their midpoints and the origin. This is represented in the video animation linked below as in the form of Tensegrity. Compression elements are shown in color, while tension elements are shown in white or light grey, representing strings or wires. Edges are shown rotated through a sequence of skew positions, to a configuration of 3 pairs of parallels orthogonal to each other. Scenes shows some illustrations of the transformation
Related transformations can be seen Here and Here
A 3D design created in vZome. Use your mouse or touch to interact.
While the models and animation above accurately represent the metrics of the tensegrities, the model below more accurately shows how such models are constructed physically. Pointed sticks with correct proportions of compression element to tension element are compared in Scenes with square ended sticks, which must be longer by the thickness of the sticks to maintain correct proportions.
