Silent cars & the blind
 

http://www.npr.org/templates/story/s...toryId=7555520

'Hybrid vehicles may pose a deadly threat to people who rely on their hearing to navigate streets and crosswalks. The National Federation of the Blind is calling for hybrid manufacturers to make their cars sound like traditional car engines, so that blind people can hear them coming.

Robert Siegel talks to Dr. Fredric Schroeder, first vice president of the National Federation of the Blind.

We confirmed the comparative noise levels of hybrid and gas-powered cars, using a Toyota Prius — one of the more popular models. Toyota officials say they are studying the issue; they also note that on the opposite side of the issue are advocates of reduced noise pollution.

The Toyota officials say that the quieter cars has led them to advise drivers and pedestrians to exercise increased caution.'

Never really had a problem with a hybrid car, but have been snuck up on by Honda Gold Wings. Perhaps this may be an issue for large bike clubs & advocacy groups to join with the blind on.

I'm all for people for not being hit by cars, including the blind, and I myself make good use of the Doppler Effect while riding, but as one who lives less than two blocks from a freeway, I'm pushing for less auto noise, not more. I think once people get used to quieter cars, they'll adjust just fine.

If you can, listen to the audio from NPR. They have a standard car passing and then a hybrid. Over the radio, I did not hear the hybrid. Quieter is one thing, nearly silent is another.

Not only the blind, but most pedestrians rely on hearing to detect traffic. And most bikes are silent too. That's why so many pedestrians seem to jump in front of us at crosswalks and on the MUPs.

Easy way to solve the silence problem: Put an active IR sensor in the car that locks the brakes if something comes out in front of the car. Sliding tires make noise.:D

this is why, when riding my silent bicycle, I go vrrrrrooooom-vrrrrrroooooooom when passing pedestrians. :p

The other day I said to a ped, "If I had a bell this is when I would ring it." It got a little chuckle.

How does a blind person do that?

I tend to agree... do we really have to add noise pollution... now that we have managed to reduce some of the other air pollution.

I will admit that the cars are quite quiet, and I too was surprised by a hybrid a while back. But I don't think the answer is to make noise.

From my observations blind people typically have a more keen sense of hearing if you will. It may be once they acclimate themselves to fact there are near silent cars they may be more attuned to the sound of the tires? I dated a blind girl years ago and she could hear things that no one else in the room noticed. When riding in my car she noticed that something didn't sound right from the previous trip two weeks earlier, she was right the fan belt broke that night:o I know in some cities that crossing lights have sounds on them to let the blind know when it is supposedly safe to cross.

Aaron:)

I thought it was the noise of the tires on the pavement they listened for, not the sound of the motor. I own a brand new vehicle, not a hybrid, but it has a very quiet engine, because it is new. I'd venture to say it would not be heard either like a hybrid would not be heard.

When I ride bike I listen for & only hear the sound of the tires on the pavement, not the sound of the motor. Often time I do not hear the motor at all or if I do it is not until the vehicle is right beside me as it passes. Yet I know the vehicle is there from the sound of the tires on the pavement.

They came out with quieter tires at one point, too, but also declared them to be too dangerous because they were too quiet. Perhaps if all the other cars weren't so noisy you could hear the quieter ones. Maybe Priuses should have a bike bell on them.

Tire noise is a good point. Particularly at night I can hear a car coming from hundreds of yards away because of the tire and wind noise, but the majority of my riding is on 55-60 mph speed limit highways. It isn't the same in town. One thing I have noticed is the sound of one car can mask that of another, effectively making the second car silent. This can be disconcerting when the second car is the one coming from behind.

Maybe we should make'em all run Ground Hawgs
http://www.intercotire.com/piclib/537.jpg

or Super Swampers
http://www.intercotire.com/piclib/628.jpg

You can hear these babies singin' from way off.:D

yes.. i agree.. the blind people driving the silent cars are a huge danger to me as a cyclist. I can't say that i'm any less afraid of the blind people driving the noisy cars though. Hey, if they can't see you... it doesn't matter what they are driving if it's bigger than a bike.

I own a Prius. I would very much dislike it if I had to have a noisemaker on my car. Quiet = efficient. I kind of like the idea of my car not making extraneous noise.

And the tire thing. Again, quiet = efficient. I'd be all for more efficient tires on cars. Saves gas.

I sympathize with the blind. It would be extremely hard to navigate the world with only hearing and touch as guidance. But putting a noisemaker on every hybrid (or electric) vehicle on the road to help a very small percentage of the population is stupid. Pardon the expression. I don't think I've passed an intersection with a blind person waiting to cross in my entire life. If I have, I can count it on a single hand - and I didn't hit him or her either. There's got to be a better way to do this.

Just how big of a problem is this, and does it justify modifying (eventually) every one of the ~200-300 million cars on the road in the US to solve this problem? Perhaps, instead of putting clackers on all cars in the future (all models of cars are eventually going to be hybridized or electrified and thus be silent - give it another 10 years), we can use this issue to improve pedestrian crossings for all pedestrians. Plenty of fully sighted and hearified pedestrians get killed at intersection crossings every year, and all of these people could use some relief.

Airzound.:beer:

Horn??...

I'll add that the type of noise maker to make the low frequency rumbling of an internal combustion engine requires a lot of power to produce (think of the power consumption of a speaker system, tweeters consume little power while base consume a lot). Putting a noisemaker on the axle of any car to produce this low frequency noise will involve a significant penalty in overall vehicle efficiency. Using a higher frequency will just be drowned out by background noise and will not have the effect that the association for the blind want.

The electric buses in Seattle used to startle the heck out of me and I can see.

I rely pretty heavily on sound to decide how much I need to slow down approaching an intersction. Sometimes I joke about being struck down by a Prius.

Most high gas mileage tires are really noisy due to super stiff sidewalls.

? how much noise does a bicycle(ist) make in comparison to a prius or insight?
A) the same, more or less...
-feel, see, hear, "taste" sometimes, and smell where/when you're riding.
air-zound if needed.
electric (or) human powered vehicles may be on an up-swing!
look out, here i go, beep-beep!

It's called "space perception". You can generally estimate the size, position, and composition of objects based on the sounds they reflect. For example curbs reflect a certain kind of noise, humans create a certain hole in the noise because they absorb sound etc.

This is not BS. I lived with a totally blind person for over 6 years and developed this skill myself even though I am sighted. It is actually easy to do, but most sighted people tend to ignore obvious sound cues. A Prius is hard to hear in a noisy environment, but a parked car that that you're walking by in a quiet environment is easy to hear. You won't know the make and model, but you'll be able to guess that you're next to a large, smooth, solid object that is probably a car. Anyone who thinks I'm full of it might constantly honk their horn for safety :D

Hey, its sounds like you would know. :)

It's been proven in 97.2% of all test cases that ZOOM ZOOM is more recognized. :D