These days almost everyone has flown a drone or heard the nasty sound they produce. Although smaller drones (up to 20 kg) are Quiet about 40 decibels Compared to traditional civil aircraft, they produce a higher-pitched noise – which people find very annoying.
One NASA study It was found that the sounds of drones were more annoying than those carried by road vehicles. And My own research It has been found that the noise of drones is less better than that of civilian aircraft – even at the same volume.
Part of the problem is that drones often fly in relatively low altitude areas that are not normally exposed to aircraft noise. This is likely to increase stress Exposed communities. Of course, if noise issues are not raised appropriately, they can avoid the widespread adoption and commercialization of drones and risk significant social benefits that they can bring.
For example, small to medium-sized drones are already used for many applications such as Medical delivery And search for missing person. Another innovation in commercial aviation is the development of electric vertical takeoff and landing (and possibly autonomous) vehicles. Moving people to cities.
Several “urban air mobility” vehicles, or “flying taxis” are currently being developed. Various aircraft manufacturers. Both drones and flying taxis will produce significantly different voices from traditional civilian aircraft and share similar issues about noise annoyance.
In 2019, I started a line of research aimed at answering two big questions: How will communities react to these new vehicles when they start working on a larger scale? And how can the design of these new vehicles be improved to protect the health and quality of life of the people living in these communities?
To answer the first question, we investigated what chain perception a drone operation might affect. Special sound environment in cities. As drone can not Flew close to more than 50 meters, Virtual reality techniques were used in the selection of urban locations to produce highly realistic scenarios with drone hovering.
This laboratory study found that the noise produced by the hovering of a small quad-copter significantly affected the perception of the sound environment. For example, a significant increase in noise annoyance was reported with drone hovering, especially in low-volume locations of road traffic. It suggested that noise production by road traffic may make drone noise less noticeable. Therefore, operating drones along busy roads can increase the impact of noise occurring in the community.
We are now testing a wide variety of drones with various operating maneuvers. We seek to gather meaningful evidence to better understand and predict and further develop human responses to drone sounds Regulation of the sounds they produce.
By integrating human responses into the design process, the most undesirable noise can be avoided in the early stages of vehicle development.
This can be done either directly with subjective testing (assessing human participants and providing feedback for a range of drone noise samples) or through the use of so-called Psycho-acoustic metric Widely adopted in the automotive industry. These metrics accurately represent how different sound characteristics (pitch, temporal variation, tone) are represented. We intend to use them to inform the design of drones. For example, optimizing the position of the rotors to make the drone less annoying.
The combination of virtual reality techniques and psycho-acoustic methods to inform the design and operation of drones would go beyond the traditional approach to aircraft noise assessment and avoid costly and inefficient ad-hoc improvements at later stages. But even more importantly, if drone manufacturers incorporate these strategies into their designs, they can build machines that are not only efficient, but also less annoying.