Getting Quiet Cars To Make Some Noise

I’ve heard several media stories about the problem of how blind people can hear hybrid cars on the street, and I’ve had one or two close calls while crossing the street in front of my house. This story by Rebecca Williams offers a good discussion of possible solutions to the problem. It’s definitely on my radar screen (see Foot rage and the Blind Flaneur), and it’s becoming more than a blip for auto makers.

The Environment Report: Getting Quiet Cars To Make Some Noise 011909:  “A lot of people who drive gas-electric hybrid cars love how quiet they are. But others say hybrids are so quiet they’re hazardous. People in the blind community say they can’t hear hybrid cars coming… and they’d like to have sound added back into the cars. Rebecca Williams has the story:

A lot of people who drive gas-electric hybrid cars love how quiet they are. But others say hybrids are so quiet they’re hazardous. People in the blind community say they can’t hear hybrid cars coming… and they’d like to have sound added back into the cars. Rebecca Williams has the story:

(tap tap tap of white cane)

Fred Wurtzel has excellent hearing but he can’t see.

He can tell by the echo from his white cane when he’s gotten to the edge of a building or the corner of a city block. And he knows cars by their engines.

(sound of car rumbling past)

“That car had a tweety bird under its hood, probably a loose belt. Now, there was a car going the other direction. (sound of truck going past) That’s a big truck, probably a UPS truck.”

But he can’t hear hybrid cars – at least not until they’re right at his feet. That’s because the electric motor is very quiet. And when a hybrid comes to a stop, the engine shuts off.

“If you don’t know there’s a hybrid car waiting, it may start turning and you may step into its path and not even be aware there’s a car coming around.”

Wurtzel is president of the Michigan chapter of the National Federation of the Blind. He says the blind community wants some sound added back into hybrid vehicles.

“’Course I grew up in the 60’s so a nice Mustang or something like that would be good (laughs)… just a sound that would let me know that the car’s accelerating or decelerating, whatever a normal vehicle would sound like.”

Well that’s one idea.

Patrick Nyeste has several ideas. He’s a researcher at North Carolina State University. He tried out 18 different sounds on his test subjects.

Everything from sirens (sound of siren)… to whistles (sound of whistle) … to engine sounds (sound of engine).

“I had a horn from a Beetle – you know, meep meep, and I would just get giggles from that.”

But, he says to make a quiet car safer, the sound needs to be continuous – like a traditional car. That means some sounds can get annoying really fast.

(sound of continuous beeping)

Yeah that’s enough of that.

Nyeste says that engine noise we heard earlier was one of people’s favorites. They also liked white noise (sound of white noise), and the hum sound (sound of humming). He says that’s because we’re used to hearing those kinds of sounds when a car goes by.

He says a sound added to a hybrid also has to be loud enough to be heard above lawn mowers and garbage trucks.

“You want to make sure the noise is heard, especially by the blind around corners, around objects, I mean some of these sounds can get masked and that’s important information to know where an object or a vehicle is.”

But some people are worried about adding sound to our cities and suburbs, they say they’re already so noisy.

Lotus Engineering says it has a solution for that. They added a four cylinder engine sound to a Toyota Prius. But the volume’s adjustable.

Colin Peachey is an engineer with Lotus.

“You could set the sound to be higher or quieter in some circumstances – so in evening, at nighttime, where you might want a lower level of noise, we could make the sound to be whatever we fancied.”

And you don’t have to hear the sound inside the car.

There’s also a startup company in California – Enhanced Vehicle Acoustics. It’s designing a similar system for hybrids.

But it’s not clear how soon quiet cars might start making noise.

Spokespeople for Toyota and the Big Three say their companies are working on solutions. And some states and members of Congress have been talking about requiring hybrid cars to make some minimum level of sound.

Then, automakers will have to figure out exactly what a hybrid sounds like.

(montage of engine sounds)

For The Environment Report, I’m Rebecca Williams.

Kudos to The Environment Report for providing the full transcript. See related article from the New York Times; National Federation of the Blind.