[Veselin Kolev]

Easiest way to make your hemispherical wheels tilt is to have the motor and wheel all tilt together. 10 lb tilting assembly, with the weight of the robot on it. Sorry, but I'll pass.

But actually... it can be done. If you think about it, as the hemi-wheel tilts, it does not change the height of the robot. All you need is strong bearings on the tilting axis, and thrust bearings on the hemi-wheel. All it takes is the will to do it, and soon enough you'll see that it isnt that hard. You know, I bet you swerve drive is harder to do.

And as for me, I would control it with pneumatics. 4 cylinders, all at the same height, digitally set. When they reach the correct height, use a double and single solenoid to lock the cylinder where it is. fun fun. I will bow to the team that pulls it off.