(For example, imagine a u-shaped craft with a low center of gravity and helicopter-style rotors on each tip. Add a third, smaller propeller on a turret somewhere for steering.)
Extremely minor nitpick: the low center of gravity wouldn’t stabilize the craft. Helicopters are unstable regardless of where the rotors are relative to the center of gravity, due to the pendulum rocket fallacy.
If you do the stabilisation with the rotors in the usual helicopter way, you basically have a Chinook (though you don’t need the extra steering propeller because you can control the rotors well enough)
A Chinook was basically what I was envisioning… what does a Chinook do that my U-shaped proposal wouldn’t do? How does stabilization with rotors work? EDIT: Ok, so helicopters use some sort of weighted balls attached to their rotors, and maybe some flexibility in the rotors also… I still don’t fully understand how it works but it seems like there are probably explainer videos somewhere.
Damn! I feel foolish, should have looked this up first. Thanks!
EDIT: OK, so simple design try #2: What about a quadcopter (with counter-rotating propellers of course to cancel out torque) but where the propellers are angled away from the center of mass instead of just pointing straight down—that way if the craft starts tilting in some direction, it will have an imbalance of forces such that more of the upward component comes from the side that is tilting down, and less from the side that is tilting up, and so the former side will rise and the latter side will fall, and it’ll be not-tilted again. This was the other idea I had, but I wrote the U-shaped thing because it took fewer words to explain. … is this wrong too? EDIT: Now I’m worried this is wrong too for the same reason… damn… I guess I’m still just very confused about the pendulum rocket fallacy and why it’s a fallacy. I should go read more.)
Extremely minor nitpick: the low center of gravity wouldn’t stabilize the craft. Helicopters are unstable regardless of where the rotors are relative to the center of gravity, due to the pendulum rocket fallacy.
I came here to say this :)
If you do the stabilisation with the rotors in the usual helicopter way, you basically have a Chinook (though you don’t need the extra steering propeller because you can control the rotors well enough)
A Chinook was basically what I was envisioning… what does a Chinook do that my U-shaped proposal wouldn’t do? How does stabilization with rotors work? EDIT: Ok, so helicopters use some sort of weighted balls attached to their rotors, and maybe some flexibility in the rotors also… I still don’t fully understand how it works but it seems like there are probably explainer videos somewhere.
Yeah, the mechanics of helicopter rotors is pretty complex and a bit counter-intuitive, Smarter Every Day has a series on it
Damn! I feel foolish, should have looked this up first. Thanks!
EDIT: OK, so simple design try #2: What about a quadcopter (with counter-rotating propellers of course to cancel out torque) but where the propellers are angled away from the center of mass instead of just pointing straight down—that way if the craft starts tilting in some direction, it will have an imbalance of forces such that more of the upward component comes from the side that is tilting down, and less from the side that is tilting up, and so the former side will rise and the latter side will fall, and it’ll be not-tilted again. This was the other idea I had, but I wrote the U-shaped thing because it took fewer words to explain. … is this wrong too? EDIT: Now I’m worried this is wrong too for the same reason… damn… I guess I’m still just very confused about the pendulum rocket fallacy and why it’s a fallacy. I should go read more.)