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earthgoodboy
27th Jun 2012, 06:14
hi,
i am working on a project to design a helicopter. Right now my task is to acquired the force required from actuators to tilt the rotor.
I have done some research and with my understanding, I am very confused on the way to get or estimate that force.
First way I tried was to use the pitching moment of my helicopter. Then, with that moment and the swash-plate dimensions, I could obtain the force needed to hold the body and the rotor in a certain position when the CG is not directly under the mask.
Other way I found is to take the moment at the shaft. When sum of the moments are equal to inertia times angular acceleration, I could get another value of force required for tilting the rotor at certain speed.

I found force value of the first method of pitching moment is quite high (30000N for 4000kg copter) and second method provides me as low as only 400N.

Therefore would really like to ask anyone or expert that could explain to me how this works. If both of my method are wrong, the alternative would also be appreciated.
thanks

cockney steve
27th Jun 2012, 14:29
It seems like english isn't your first language!

Other than that, have you also considered the gyroscopic precession of the rotor-mass? have you also considered that the swash-plate doesn't actually tilt the disc per -se, rather it alters the blade -pitches so the disc tilts itself.

I'm NOT a helicopter engineer, so don't accept the above as gospel. I DO have an interest in R/C model helicopters and suggest that you buy a used 30-90 size, either nitro or electric and you'll have a basic model to study the various features that make these overgrown egg-whisks beat the air into submission.

Models are NOT toys, they can and HAVE decapitated people...treat them with the utmost respect.......learn more on Runryder, the leading model Heli forum.