[Clem1640]

I like the use of the ball shifter in this application, but I've got some questions

It looks as if your drive shaft (3/8" of 1/2") is your pivot axle and is taking all of the axial, radial and shear loads. I would expect this shaft to fail in use.

What bears the weight of the robot (the axial load)?

How is the rotating pivot cage secured to the vertical drive axle? This will be a high-load joint, but I don't see how this is done in the drawing.

A clever approach.