The Action Lab looks deeper into why strange-shaped objects like this octohedron can roll. A lot of it is about friction, or lack of slipping. Part of the issue is probably materials as well, as an object has to be sufficiently dense for the rolling to continue. These heavier objects just need a shove of [&]

https://boingboing.net/2020/09/01/this-square-shape-can-roll-bu.html