Unity3D: Simple Physics Based Helicopter
MagzTV accidentally described how a helicopter flies in an amazingly intuitive way that I've never seen before. Watching how the War Thunder helicopter flies I noticed that my helicopter was wrong in EXACTLY the same ways. After seeing the explanation of why it was wrong and how to make it right, I was very curious to try making some simple changes to an old helicopter prototype would result in.
There were two main changes I made. The first was that that all forces were now applied at the positions they would. This means that the rotor applies lift above the center of mass, pitching and rolling is induced by tilting the rotor blades while yaw is induced through a tail rotor. The second was that I brought in the SimpleWings from a previous project and added wings in reasonable places.
The results are pretty amazing. It's a night and day difference and the helicopter now flies similarly to how is described that a realistic one should. With just these two changes, a great many properties of helicopter flight just emerged naturally as a consequence of the forces involved.
The main example he used was how rolling onto the side did weird and artificial things in the fake physics, but with realistic-ish physics, once you pass a critical threshold you just kind of lose control because of the way the forces are being applied. You can watch my inputs and it's just doing it all on its own once I passed like a 45 degree bank angle. It was super neat.
Another example is how the helicopter is kind of self-stabilizing to an extent. With the center of mass below the rotors, it generates torques on its own to put the helicopter into an almost hover. It won't hover precisely or anything, nor would it in real life, but there is still a sense of the helicopter always trying to correct itself just due to how its forces are applied.
Really neat stuff. I also might be talking completely out of my ass because I don't really fly helicopters in sims much so I don't have as much of an intuition of what should happen as I do with planes.
Music is FEEL the POWER in YOUR SOUL
by Hideki Naganuma