This project was motivated by the need for cheap weatherproof absolute rotation sensor in my robot sailboat work and seeing GeekMomProject's Bendy SAO badge add-on, which could benefit from some rotational position sensing. Customs PCBs are of course very cheap (and form the body of the Bendy SAO), so they are the obvious choice of component. 

Capacitive touch is a nearly universal feature on modern microcontrollers, so I thought that was the obvious place to start. This was not the slam dunk one would hope (as will be documented in the logs), but did point me in a better direction.