posted to Github.
This toy serves as a kind of analog bridge between two remote spaces: the column of ultrasonically-oscillating air in front of the remote, and whatever body part happens to be in contact with the vibrator. Touch that invisible space above the remote, and the vibrator touches you.
In fact, it does start to feel like there’s a palpable object in space above the remote’s sensors. Move your body close to it, and it reacts. Press into it lightly, or tease the edges. Flick your hand through it, or make graceful waves back and forth. You can use your whole body to touch it, almost like a big fuzzy vibrating cone floating in air.
If the sensor can see your body’s rhythms, it responds in kind, effortlessly synchronizing to its frequency. This is exactly the sort of closed-loop control I was after.