Howdy HN! I thought some folks might find this instrument kind of interesting.

Here's a demo of the instrument built using a drone motor with a 3D printed wheel that holds magnets to vibrate a pair of strings. https://www.youtube.com/watch?v=ds2I0QujzO0

If you want to build your own OSC Rotary Magnetic Bow, the source code and 3D model are here: https://github.com/spDuchamp/OSCRMB

You can listen the album "Autonomous Drone Lullabies" here: https://www.youtube.com/watch?v=1fuSljzgWFc

Happy to answer any questions.