Dear Heinrich,
I wish to congratulate you for your excellent description of the Zero-G movement.
It is the only "engineering point of view" available on Internet relating to the transmission
of movement through 2 angular disturbances (2 degrees of freedom)
Other elementary information, and especially images, appear in the interview with the chairman of Zenith:
forumamontres.forumactif.com
On my side, I drew the Pichard&Besson's network graph:
documents.epfl.ch
French Engineers Pichard & Besson are authors of the
"General Model representative of the Power transmissions":
wiki.epfl.ch
This method proves very effective to model a network
of differential gears like the Zero-G movement.
Thank you for your great contribution !
Best regards.