Ulysses is astronomically unlikely as a result of nature’s tumbler
but a perfectly round stone is not. A lot of science is a mimicry of
nature. Also I repeat the maxim of Professor Warwick in “March of
the Machines” (1997). If there is anything humans can do, a machine
can do if you separate out the SPECIFIC tasks. I think it is an R&D
project but I am quite sure that a totally automated sphere-making
(bead-making) machine is do-able although it may not be a tumbler or
the tumbler may be only stage one. Perhaps Mr. Livick the
roboticist, who is on Orchid can comment.