An underactuated propeller for attitude control in micro air vehicles

Abstract — Traditional coaxial helicopter micro air vehicles use a large propeller motor in conjunction with two small servomotors to control thrust, pitch, and roll forces and mo-ments. Quadrotors similarly generate these necessary forces and moments through the coordinated control of multiple actuators. We present a novel propeller architecture which allows a single motor and rotor to express such control by modulating the torque applied to one passively hinged, underactuated propeller. Flight tests of a two-motor coaxial helicopter demonstrate that such a system can provide active stability and control in a real flight system. I