The clever thing about the globe is that it doesn't do arbitrary rotations, so the mechanical connections are simplified. Instead, it has two degrees of freedom

The clever thing about the globe is that it doesn't do arbitrary rotations, so the mechanical connections are simplified. Instead, it has two degrees of freedom through two fixed, co-axial shafts. Specifically, the globe rotates at an angle of 51.8°, corresponding to the launch angle of the spacecraft. Spinning the globe at this angle gives you the orbital track without any real computation. The other rotation is the Earth around its axis. The trick here is that the equator is a fixed frame, while the two hemispheres are rotated based on the input shaft.