Acoustic characteristics of a quad-copter under realistic flight conditions

Abstract

The noise features of a commercial quad-copter were experimentally studied in an anechoic chamber. Flight conditions including hover, climb and descent, as well as cruise and yaw, were tested. The measurements were conducted in a controlled environment and factors that may affect outdoor testing were avoided. The drone noise was measured by a ground-based 8×9 rectangular microphone array, as well as a linear array composed of eight microphones placed vertically. The linear array provided insight to the sound radiation characteristics along the propeller plane and the ground array provided a contour map of the sound pressure levels, and this information brought insight to the azimuthal symmetry of the noise source as well as the preferred radiation direction. A binocular vision tracking system synchronized with the noise measurements, was used to trace the drone position. The combined noise and position data captured the changes in the noise characteristics across the flight tests. © 2019, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.