Beep, Beep: Pedestrian Warnings for Electric Cars Need to Be Obnoxious
Congress hasn't been able to agree on much lately, but it did pass the Pedestrian Safety Enhancement Act last year, which will soon require all very quiet hybrid and electric cars to produce warning sounds for the benefit of nearby folks on foot. Automakers knew this was coming, and they're starting to wire their cars for pedestrian-alert sounds. Unfortunately, their approach is too subtle to be effective.
So far, the blind community (the major driver for this legislation) is underwhelmed. The problem is that the sounds on the few cars so equipped aren't loud enough, and some come with on-off switches that defeat the whole purpose.
We're all familiar with the loud beep-beep that big trucks make when backing up. It's incredibly effective, and you can't miss it. On cars like the Nissan Leaf, however, the sound is much more unobtrusive (check the video below). And -- probably because the automakers don't want to offend anybody -- it comes across more like lull-you-to-sleep ambient noise than a persistent warning.
Sounds great... in the lab
Chris Danielson, a spokesman for the National Federation of the Blind, told me:
Some of the sounds I've heard don't stand out, and the manufacturers will have to work on them. It's not just making the sounds louder -- different pitches and tones are going to be more audible. One I heard sounded great in the parking garage, but once it was out in traffic there was a world of difference and it was much harder to hear.The Leaf's system has another flaw -- it can be switched off at any time, and many owners are going to take that option. The Chevrolet Volt's sound is only turned on by the driver pulling a stalk, so it's far from the automatic warning that the law will require.
In general, the systems in place now over-think the sounds cars need to produce, and it may take the federal law that will be phased in starting in 2014 to get the automakers on message. A system available in Japanese-market Toyota Priuses, for instance, is synthesized to emulate a whirring electric motor, and Auto Guide says:
It sounds to us like a B-movie sound effect of an alien spacecraft--If there were a theoretical hack to change the noise to something totally different it would be tempting to ditch the gentle purr of an electric motor for something more sinister -- like a velociraptor.The Leaf's switchable sound is also synthesized, and something like a quietly menacing whirr out of Blade Runner. You can't hear it inside the car. Nissan says it "worked to avoid a sound range that would add unnecessary noise to the environment," which it certainly achieved, though adding noise to the environment would seem to be the point. You could argue that warning sounds in electric cars defeat one of their chief virtues -- their incredible quietness in a world of din. But if we're going to require the warnings, they have to be effective.
The 2012 Lexus CT 200h introduces a Vehicle Proximity Notification System with sounds that vary with speed, and shuts off at 15 mph. It comes on only when the gas engine is turned off. I appreciate the sophistication of that changing tone, but the sheer variety may mean that no single sound becomes identifiable as a warning.
An auto spokeperson I talked to told me, off the record, that it would be great if the car sounds could be "like downloadable ring tones, and they'd debut new possibilities at the auto shows." No, no -- that's fun, but it's a non-starter and totally the wrong idea. There's music all around us, especially in urban settings, and there's no way sounds like that would produce a warning. We really need something simple and universal like those backing trucks. Beep, beep, it works.
Here's what the Leaf sounds like going forward; there's a separate sound for backing up:
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