Hello! So, pet project. Basically, I'd like to be able to monitor the distance between two moving points, with distances varying from 0-2m or so, with a resolution of at least 5cm or so. (The actual application is to measure the distance between a person's feet while moving, running, jumping etc.) The two points will not be in a particular line (3D movement of both), and since I can't guarantee that their orientation will be controller, the usual IR or ultrasonic sensors I've seen won't work. I am allowed to strap something to each ankle. Any simple sensors that I might want to look into that you can suggest? All I need is constant updates on the distance, I don't care about direction. Thank you all!