Ri3D FIRST Capital also attempted to climb with pneumatics, but they used 3 cylinders. They posted a video of their climb: https://youtu.be/fgUumESVXhE
They said they used 1.25” bore, 7” stroke for 2 back cylinders and 8” stroke for the front cylinder.
(post: FIRST plays Ri3D on FUN!)
My team is also thinking about using four cylanders to climb to level 2, so I’m really intrested to see how testing goes.