No, not swinging. Spinning. It's for a POV display on an LED poi. The issue here is that the direction of rotation can (or rather will) change, so I need to detect which way it's being rotated so I know how to display the data. And everything needs to remain enclosed inside of the LED bar. The performer is holding a leather loop which is attached to a chain to which the LED bar is attached to.
And I also need to detect the rotation speed so what's being displayed stays in one spot or right side up, regardless of whether the performer is spinning it fast or slow.