>>1014347
Anon can you guess what I have on my desk right now??
In any case if you used your brain a little you would understand that three knobs provide exactly half of the axes of a 3D mouse. Even if you had six knobs, you wouldn't have enough fingers to operate it with one hand. And the standard E11 rotary encoders have 20 stops in a full rotation, which is far too few to encode rotations. Among other problems. I literally tried this and then bought a pair of spacepilots for 100€ total. 50€ a piece.
You really should start trying out your great ideas.