Tis was a grabbing mechanism I designed the Saturday of kickoff. Unfortunately we won’t be building it, so I don’t get to see it in action
It’s two pneumatic 4" cylinders that provide wrist and grabbing movement. It would be attached to the end of an arm. In the case of the overall design in my head, a telescoping arm with a 180 degree pivot, similar to one of the 60s robots from 2005 (66, I’m pretty sure, never found a picture of that robot). I did the fingers as tubes with triangles cut out, bent into shape and then welded. More complicated (and probably weaker) than simple bending with a tube bender, but pretty flipping sweet looking, as it looks more like the joints of your finguers. The curved bars between the front two prongs would ideally keep the donut from rotating in your grip.
Oh, and I did this with Solidworks (I’m a college freshman mentor, former student, for/of FRC Team 1015, PiHiSamurai)