MIDI Breath Controller

Deep breathing isn't only for mindfulness, it's for sending MIDI CC messages too. You can build a MIDI breath controller with a BMP585 air pressure sensor. This particular sensor has a port that you can attach a tube to for targeted pressure readings. In this scenario, the sensor is attached to a QT Py RP2040 running CircuitPython code that maps that pressure reading range to MIDI CC message values.