something beginning with Y. See Beard for why I’ve referred to psi.
Sometimes I amaze myself with how stupid I can be. I’ve been ignoring yaw for a long time because:
- a quad shouldn’t yaw due to its prop rotations
- if it does, there’s nowt can be done to stop it.
But from another long chat on the Raspberry Pi forum, the completely obvious point finally became obvious to me: although yaw can’t be prevented, it still needs to be accounted for in drift correction. The fix for forwards drift plus yaw is almost certainly not reverse acceleration, and in the extreme case, with say 180° yaw, it may be forward acceleration needed probably along with some left or right also.
I’ve wasted months on drift control which couldn’t possibly work without including yaw.
For the moment, I’ll just cross my fingers and use the integrated gyro z axis, but I now definitely need a compass for longer flights.