This asymmetric rolling shape is based on the 3-4-5 right-triangle. The perimeter is constructed from three arcs of a semicircle, with total length π * r, where r is the common radius of curvature. The shape does not have constant width like the Reuleaux polygons. The construction was created using the Geogebra interactive geometry application. Using a semicircle of fixed radius, the chord lengths in ratio 3:4:5 were found by iterative adjustment.
