Overview: The Spidron is a planar figure consisting of two alternating sequences of isosceles triangles which, once it is folded along the edges, exhibits extraordinary spatial properties. The Spidron can be used to construct various space-filling polyhedra and reliefs, while its deformations render it suitable for the construction of finely adjustable dynamic structures.
With details: A spidron is a plane figure consisting of an alternating sequence of equilateral and isosceles (30°, 30°, 120°) triangles. Within the figure, one side of a regular triangle coincides with one of the sides of an isosceles triangle, while another side coincides with the hypotenuse of another, smaller isosceles triangle. The sequence can be repeated any number of times in the direction of the smaller and smaller triangles, and the entire figure is centrally projected through the mid-point of the base of the largest isosceles triangle.
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