Mathematicus - Solids of constant amplitude based on the Reuleaux triangle (Italian language)

These solids of constant width behave like spheres. This is because, regardless of the particular shape, the diameter is always the same at every point. You can demonstrate this property by placing a flat object, such as a book, on them and it will roll smoothly as if the object were on spheres. Plus, these wobbly shapes won't roll away. The precise form is an orbiform based on the revolution of a Reuleaux triangle. The enclosed booklet describes some applications, such as the rotor of the Wankel motor or the drill bit that makes square holes (not practicable with this product). Sold in sets of 3.