I made a Model of the ABENICS active ball joint mechanism, which uses a spherical gear meshing with two monopole gears. The spherical gear has 32 teeth, while each monopole gear has 16 teeth, with a module of 2 for all gears.
This novel mechanism is particularly intriguing, and I believe the best way to fully understand its principles is by working with a physical model.
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The author marked this model as their own original creation.