In this design, much of the kinematics regarding our setup is the same. However we looked to tackle much of the underlying problems with design 3 of our drawing arm.
In order to fix the permanent magnets to the freely rotating gears, we purchased a low carbon steel sheet from McMaster-Carr which we would then plasma cut and place directly in the middle of a freely rotating gear. The sheet could then be bolted down on either end and voila, we have a magnetic mount.
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Solving the wire problem was a bit more complicated. We decided that by using a set of electric motor carbon brushes, we could transmit current from a brush to a steel plate, so long as the brushes would remain in contact with the steel plates. The plates could then rotate with the fixed gear, providing all of our solenoids a source of either power or ground depending on which steel plate it was wired directly to.
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Although this design theoretically would work, we soon realized our project was coming to be unnecessarily complex. One of the most critical lean manufacturing principles is the idea of Takt Time. If a product takes more time to develop than the amount of time you currently hold, it is not a wise decision to continue forward.