Do nothing machine

thingiverse

Archimedes' Trammel is a mechanical device that produces the shape of an ellipse.[1] It consists of two sliding shuttles, confined to intersecting channels or rails, and a connected rod with pivots fixed at specific points along its length. As the shuttles move back and forth in their respective channels, the end of the rod traces out an elliptical path. The semi-major axis 'a' and semi-minor axis 'b' are equal to the distances from the rod's end to each pivot point.