I went all gung-ho (from Chinese 工合 …who knew!) into modelling the cross spherical gear (CSG) and monopole gears (MPG) on the ABENICS system. I have since 3D-printed them out and I think they are fine (ie they seem to mesh correctly). I’ll do a post on how I adapted for print in time, but in meantime, the STL models are here.

The gears finished, I thought I might tinker with the maths. To be honest I had been ignoring the mathematics since I was only initially interested in modelling the gears in Fusion 360. Essentially, we want the SCG at some (Euler) angle and need to know what angle to dial into our motors pairs driving the two MPGs to achieve this.

The paper includes the derivation of the rotational relationships, so I decided to try and mock up virtually (using three.js in browser).

Below and here on github is as it stands. Needless to say, it is not working!

Anyway. I thought I might put it out there. I am kind of done with it for the moment.

Too hard box for me at the moment, particularly since I do not really have an end project in mind for the ABENICS system. Maybe someone else can fix my mess.