Dogbone instead of swashplate?

[IkonOne]

Hi. I am completely new to this hobby. BUT, I am coming up with ideas already. Allow me to explain.

I REALLY got into helis when I came across the pixeleto(pixeleto.reference.something I THINK is the website). Anyway, the builder states that the heli has 4 channels meaning yaw, pitch, roll, throttle. He also goes on to explain that the helicopter has no swashplate. This intrigued me and to this day I am still trying to figure out how you could control the pitch and roll with no swashplate. And what I have come up with so far is a dogbone.

Now in trying to come up with a solution to making a dogbone work, I have detailed several problems. Mainly, vibration.

What I have in mind goes like this. Motor, gears, shaft, dogbone, then above the shaft above the dogbone, a bearing with a swashplate like servo attatching rig thingamajig, blades.

Now this solution(If you understand what the hell I am talking about, I will try to provide some sort of diagram to clarify my piss poor explanation in a future post) would be practical on small helicopters I beleive. It DRAMATICALLY reduces the number of parts needed for pitch and roll control. BUT there may be serious vibration issues due to the fact that a dogbone is not inherently stable on its own. In fact any dogbone that I have used in my rc cars still seems to have play allowing it to rotate slightly(which is not supposed to happen) which could amplify vibration.

Any suggestions, comments, experiences, or better solutions to this would be greatly appreciated and more solutions would be interesting to see what other ideas may be out there. Hopefully something effective comes about and I can attmept to build my own "picocopter" to destroy along with my blade cx.

I will try to get a diagram up sometime tonight.

[IkonOne]

I think I figured it out.

The entire rotor assembly down to the motor/gears sits on its own platform. The shaft is through a hole of sorts and the servos move the botom of the platform moving the blades in the opposite direction(the "hole" that the shaft goes through acts as a fulcrum). The theory is that the shift in the body weight will change that angle of the blades. Although this solution may be plagued with the problem of a VERY small amount of control. Hmmph...

Now to figure out how the assembly is mounted. Minorly daunting but I believe that this is a better solution.

[nullie]

Rotor is heavy, spins fasts and act as a gyrostat. Body is very light, and won't affect it's rotation much. So it'll end up swinging body with controls, but no actuall effect on rotor movement...

[IkonOne]

:/ your right... I am jsut trying to figure out how the pixelito does it... anyone know? I know that it doesnt even use servos. Or so the website says.

[dbcisco]

Not sure how the pixelito works. As to replacing the paddle bar with a dogbone.. the answer id quite simple. The servos move the swashplate which changes the pitch on the paddles, lift on the paddles changes pitch on the blades and thus their lift. The reason is to relieve stress on the servos. You could move the blades directly and use a dogbone but a) the servos might have t be changed and use up more battery b) the links from swash to blades/paddles would have to be reversed. Tried this on a DF4 but the link holes are different sizes (blades/flybar) so I would have to make links. I only put this on the backburner when I decided to make a four blade rotor for it (in R&D now) have darfstmen and CNC lab working on it. I figure I might as well go full tilt on mods if I am going to put in alot of time. Actually the rotor seems to be esier to make than cutom links.
The dogbone id used alot on 2ch 2blade helis like the Syma 9093.