This instrument is a quick prototype that could lead to some much bigger ideas.
In a lot of my droning machines I need to place the motors as far from the pickups as possible to avoid interference/noise being generated from the moving parts. With this instrument I've used that noise/interference to my advantage to generate a dirty-synth sounding tiny machine.
Using a small variable resistor to control the speed of the motor you can get different pitches of noise/interference when that motor is next to a pickup. Add a simple switch and you can get results like this:
Very very basic stuff, it could be replicated using two motors sat next to each other too instead of the transformer I used as a pickup in the prototype.