Efficient and Quiet Rotors Through Variable-Pitch Control

In addition to classical quadcopters that utilize rotational speed to adjust thrust and torque, the potential of combining variable pitch with rotational speed to augment maximum thrust and power loading, as well as to alleviate noise emission, is explored. Through a large data set of numerical simulations under different combinations of pitch and rotational speed settings, fitting models for torque, power loading, and acoustic emissions have been built. Optimal combinations of rotor pitch and rotational speed for aerodynamics and aeroacoustics have been suggested based on the fitting maps. By comparing flowfield data of variable-pitch rotors with those of fixed-pitch rotors, a strategy for improved performance has been elaborated. The presented framework establishes the foundation for a flight control strategy targeting optimal propulsion efficiency and quiet flights.