I want to measure the airflow around the perimeter of a "toy drone sized" spinning propeller.
I've built an X/Y gantry with a servo on it capable of moving the instrument from the back near the hub, our around the end and back to the middle of the front of the hub.
Can anyone think of a way to work out the wind speed and three-dimensional direction with some kind of instrument attached to the end of my servo arm? I need this as small as possible for accuracy reasons (e.g. the size of a pea). The data from this "air scanner" feeds into a generative design optimisation process.
Ideas I had include using some kind of magnet with a magnetometer IC (but not sure how I would mount that), using a tiny optical sensor and tiny set of spinning blades, measuring resistance through a bunch of tiny heated wires that have half of their surfaces insulated somehow, a tiny pitot tube, a high speed camera and smoke... but none of those give me confidence that they'll be ideal, or even accurate, affordable, or work at all... I need more inspiration!
Keep in mind that the airflow changes direction by at least 180 degrees at the tips, and it's never going "straight" (the flow twists a bit in the direction of the blades), and it almost certainly suffers extreme turbulence, especially every instant that each blade passes by.
