Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: Handmixer.com on October 29, 2006, 01:23:30 AM

Title: Hlicopter
Post by: Handmixer.com on October 29, 2006, 01:23:30 AM
I have decided to build myself a R/C helicopter, but I have no clue how to go about it. My knowledge of helicopters is very limited. I know how to make it turn, and go up, but that is all. Can anyone help me with things like tilting foward and backward, as well as descending, making the rotor and blades and choosing the right motor?. I want it to be able to carry about a Kilogram on top of its own weight.
Title: Re: Hlicopter
Post by: polar bear6 on October 29, 2006, 05:33:45 AM
well, building a helicopter isnt an easy task, and not a big one as you want it too, 1kg is alot of weight.
http://www.angelfire.com.nyud.net:8080/blues/heli_project/
there you can get tips and stuff, but I think building a helicopter is a very hard thing to do.
Title: Re: Hlicopter
Post by: Admin on October 29, 2006, 12:38:06 PM
There are many types of helicopters (dual rotor, quadrotor, etc.), so the difficulty is dependent on that as well.

I recommend buying a cheap rc helicopter toy from radioshack and hack it to figure out how it works.
Title: Re: Hlicopter
Post by: Handmixer.com on October 30, 2006, 11:31:55 PM
Maybe 250 grams is more realistic.

I have figured out ascending and descending, left and right, but still can't puzzle out how to make the copter lean fowards or backwards. All I can think of for this, is to have a rack and pinion with a weight on it. but that will be heavy.
Title: Re: Hlicopter
Post by: JesseWelling on October 30, 2006, 11:42:33 PM
don't heli's use gyros for some purpose?

Seems like if you had a good enough gyro you could tilt it which would exert a tourqe on it....tiliting the copter maybe?

Admin is a Mech E ask him.......
Title: Re: Hlicopter
Post by: Admin on October 31, 2006, 09:44:28 AM
Real helicopters tilt the main rotor in the direction of travel to move.

If that isnt possible you could use a shifting weight, or an additional vertical tail rotor, for pitch.

what I found online:
"Normally the lift produced by the rotor aims straight upward, but the pilot can tilt the rotor blades with a device called the cyclic pitch control to make the helicopter fly in a particular direction. Although most of the lift force still points upward, some of it now also points to the front, back, left, or right, tilting the entire helicopter and pushing it in that direction."

This site has good pics too
http://www.copters.com/mech/mr_semi.html
Title: Re: Hlicopter
Post by: Handmixer.com on October 31, 2006, 11:23:19 PM
Thanks for your help guys, I had a look in a book I have, and it told me. Originally, I had thought that the cyclic control was driven by a single servo, and could only alter the rate of ascension and descension, but the book said that you have two servos and you tilt the swashplate to go forawd or bacward, or raise it or lower it to go vertically.

Next question. How do I make a swashplate?