Designing for Calmness: Early Investigations into Drone Noise Pollution Management

Drone use is increasing rapidly within civil society, making their sound profiles - and potential contribution to noise pollution - increasingly relevant. Noise pollution has been demonstrated to be a public health risk including contributions to hearing impairment, hypertension, heart disease, dementia, sleep disturbance, decreased school performance, and annoyance. High-frequency and tonal noise has been identified as being particularly annoying to humans. In this work, early investigations into designing drones for calmness are explored, inspired by ethical considerations and empirical evidence about human perception of drone sounds. Experiments conducted in an anechoic chamber on a small (250 gram) quadcopter drone using one, two, and three-bladed propellers showed sound pressure peaks with fundamental frequencies at 116 Hz, 178 Hz, and 316 Hz respectively and sound pressure levels of 77.4, 76.6, and 76.4 dB(A) respectively at a distance of one meter. Therefore, in this case-study, less annoying lower- frequency sound can be achieved using single-bladed propellers. When designing for calmness, explicability should also be considered - a drone that is still audible can prevent spying and enhance trust. In the future, designers and manufacturers could increase public acceptance and reduce public health impacts by designing drones for calmness.