The Sound of Silence: Designing Electric Vehicles for Safety

Near-silent electric vehicles pose a danger to people with visual impairments, so engineers are studying ways to make the vehicles audible while maintaining the benefits of quieter streets.

Read Time: 2 minutes

August 17, 2022, 10:00 AM PDT

By Diana Ionescu @aworkoffiction


“The electrification of mobility presents humanity with a rare opportunity to reimagine the way cities might sound,” writes John Seabrook in the New Yorker, replacing the grating noise of gas engines with the quiet smoothness of electric vehicles. But car noise can also be an important warning mechanism for people with visual impairment and all pedestrians. “Not only does engine noise announce a vehicle’s presence; it can also convey its direction, its speed, and whether it is accelerating or decelerating.”

According to a little-known 2010 Congressional act, “every E.V. and hybrid manufactured since 2020 and sold in the U.S. must come equipped with a pedestrian-warning system, also known as an acoustic vehicle alerting system (AVAS), which emits noises from external speakers when the car is travelling below eighteen and a half miles per hour.”

The article outlines the development of electric car soundscapes, which have become more specialized as research reveals the most effective sounds for both pedestrians and drivers. “Automakers have enlisted musicians and composers to assist in crafting pleasing and proprietary alert systems, as well as in-cabin chimes and tones.” The question is more complicated than one might imagine: “How do you put into regulatory legal language that a car should sound like a car?” asks John Paré of the National Federation of the Blind.

Meanwhile, electric cars must still be loud and distinctive enough to be useful. To that end, we could end up with a future just as noisy as today, “a cacophony of sound and dissonance if these cars are all singing different tunes, in different key signatures and pitches,” says Douglas Moore, a senior expert in exterior noise at General Motors.

Monday, August 1, 2022 in The New Yorker

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