Pitch Curve for Realistic Scale Like Flying


Micro helis can fly and maneuver quickly, but they are not elegant flyers. Watch any videos, and you see them fly like grasshopper. They take off and immediately jumps into the air like a grasshopper. When they land, they smash into the ground. Real helicopters don't behave like that. Real helicopters have a lot of inertia, and every movements are gradual and graceful.

How can we make thess micro helicopters behave more like a real helicopter?

One way to to change the pitch curve to make it appear like the micro helicopter has a lot of "mass". Below is a strategy on how to accomlish this. Further below is an explaination on the dynamics of why this adds appearant "mass" to the helicopter if you are intersted in the details.

How Does the Scale Realism Pitch Curve Works

Adding Appearent "Mass" to Micro Helicopters

Real helicopter has alot of mass, and takes time to respond to throttle input. That makes them very elegant flyer. That is why I love helicopters in the first place. Micro helicopters are a little disappointing in that they jumps around up and down like an insect. They weight next to nothing. In the above pitch curve, the pitch actually drop from zero throttle to about 50%. Take off point is around 40%. From take off to 50% throttle, the pitch actually drops instead of rising like in a typical pitch curve. This means that right after take off, throttle advance will actually drop the pitch and loose lift instead of gaining lift. The rotor has to speed up to compensate for the drop in pitch before the helicopter goes up anymore. Therefore, the take-off is slowed down. The motor has to overcome the inertia of the rotor and speed up the rotor before the helicopter gain altitude. The result is that the helicopter raise slowly, and acts like it has a lot of weight.

Descending is the opposite of accending. With descending, the rotor has a lot of rpm. Going from 60% to 50% throttle, the pitch goes up even as the throttle goes down. Therefore, with the excess rpm and inertia in the rotor, the increase in pitch even as the throttle is cut will cause the helicopter to hover longer before gradually coming down as the rotor sheds rpm. This again gives the illusion of mass for the helicopter. With further cut in throttle, the picth goes up even more. When landing, the helicopter will appear to linger longer in the air before coming down.





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