Variable pitch! Waterproof! This thing is awesome. Surely there is different tuning when it's in water vs when it's not, right? How do you detect the transition? Motor currents? This is a really neat project!
In their report (https://gitlab.com/hybrid-drone/paper) the authors mention that they implemented one controller for flying and another for diving. The transition seems to be initiated manually, but they propose a few ways of automatic detection and transition.
