Spherical Parallel Manipulator

Brilliant design, thank you! For those who want to build this: tolerances are very tight, it took a lot of sanding for me to be able to get the 608z bearings in their slots and still, I couldn't get them to go all the way in - I think this is why the center point is a bit off on my make, as the bearings didn't go in fully, I think the center point got a bit lower - the pin's head has a slight movement in every direction instead of remaining in the same point in space. Also, the 60mm M6 bolt used to hold the assembly together is slightly short, a 65mm one would work better. The print turned out great and the entire piece is mesmerizing to play with. Will try it with a shorter pin to see if that fixes the going off-center issue.