BXFlyer Four Rotor Helicopter

Posted 9 Dec 2003 at 19:39 UTC by steve

Bruce J. Weimer, MD decided to build an autonomous flying robot a few years ago and the SRS recently published an article he wrote about the results. He chose an electric powered, four rotor design similar to the Dragon Flyer. Bruce's robot is controlled by a BX24 microcontroller programmed in BASIC. His robot also looks very similar to the original prototype of the Dragon Flyer, which makes an occasional appearance at DRPG meetings.

Gyroscopic four play, posted 9 Dec 2003 at 21:41 UTC by Frank McNeill » (Apprentice)

Weimer described his autonomous version of a radio-controlled "Roswell" or "Dragan" flier as having two rotors with CW rotation and two with CWW rotation. He expressed surprise that the four rotors didn't provide the gyroscopic stability he expected from this configuration. The reason for this is that counter rotating gyroscopes cancel one another out if they are fastened to one another or to a common frame. If you push the top of the frame of a spinning gyroscope in one direction, the gyroscope it will respond by tilting in a direction 90 degrees from the push in the direction of rotation. Tilting a frame with two attached gyroscopes spinning in opposite directions would cause the gyroscopes to respond by trying to tilt in opposite directions, which would ouf course cancel out the stabilizing effect that Weimer anticipated.