Electric Cars and the Sound of Silence

 

Electric vehicles (EV's for short) are not so common where I live that they are even an every-day encounter, although being within 30 miles of the Austin Tesla plant, we do see Teslas fairly often on the highways.  But a problem that had never occurred to me about electric cars is currently being intensively studied by most car makers, and the result will affect how cityscapes sound in the future.

 

If an electric car moves faster than 20 MPH or so, its tires make enough road noise so that it's not that much quieter than most modern internal-combustion-engine (ICE) vehicles.  But at speeds lower than that, but fast enough to cause injuries in collisions with pedestrians, you simply can't hear them.  The electric motors are nearly silent.  And for visually-impaired and blind people who rely on the sounds of ICE vehicles to navigate, this can be a real problem.

 

As reported by John Seabrook in a recent New Yorker article, way back in 2003 a friend came by National Federation of the Blind activist Deborah Kerr Stein's house driving a new Toyota Prius, which in its battery mode was so quiet that Stein couldn't hear it at all even as it passed within a few feet of her.  She thought at the time "We've got a real problem."

 

After numbers of experiments with different electric vehicles and investigations into pedestrian accidents involving electric vehicles, it turned out that not only blind people, but sighted pedestrians also had problems noticing electric cars because they were so much quieter at low speeds than ICE vehicles.  Statistics reported in 2011 showed that hybrids and EVs showed a 35% greater chance of being involved in collisions with pedestrians and a 50% greater chance of collisions with bicyclists. 

 

This evidence was used to persuade Congress to pass and President Obama to sign the Pedestrian Safety Enhancement Act in 2012, which called for a "sound or set of sounds for all vehicles of the same make and model."  The National Highway Traffic Safety Administration (NHTSA) took six years after that to devise technical specifications saying how loud and in what frequency ranges these sounds must be, and now the various car manufacturers who either sell or think about selling EVs must comply.

 

Seabrook interviewed numerous sound designers and engineers at GM, Renault, Ford, and other makers, and many of those interviewed were looking forward to contributing to an entirely new aspect of automotive history:  artificial characteristic sounds. 

 

For most of the time that people have lived with ICE vehicles, we have unconsciously learned to associate certain kinds of sounds with certain vehicles.  Seabrook even unearthed an acoustic engineer who could tell the make and model of a car just by the sound of its engine idling.  To me, most cars with their engines running just sound like cars, but the one exception that comes to mind is the exhaust noise made by the old-style VW Beetle produced from the 1950s to the 1990s or so.  It had a characteristic high note that made the sound unmistakeable for anything else.  But for the most part, automakers regarded sounds made by the car as something to be minimized, and many smaller vehicles going above 30 MPH or so don't make much more sound than an electric vehicle does.

 

But now we're going to have to get used to the different sounds devised by car makers to characterize their individual EVs.  Presumably, the EVs on the road now meet these requirements, but Tesla, the current leader in numbers on the road, has had run-ins with the Feds regarding some acoustic options that were installed for a time.  After a 2020 software update, Tesla drivers could play goat bleats, ice-cream truck music, and various less presentable noises through the external speakers installed in every Tesla.  The NHTSA clamped down on it and thereby earned the title "fun police" from Elon Musk, but Teslas are presumably still compliant with the Pedestrian Safety Enhancement Act.

 

This set of developments presents a relatively rare case in which a potential engineering problem was noticed and headed off before the number of potential problem vehicles got too large to deal with conveniently. This benign outcome was enabled by an alert "mediating institution"—the National Federation of the Blind—which was accustomed to dealing with governments and helping to draft legislation.  And it has the side benefit of making EVs safer for everybody else too, as many accommodations for the disabled tend to do. 

 

The mediating institution in this case is a privately owned and operated organization, and the profession of engineering has many such entities dealing with largely technical matters:  setting standards, organizing new protocols for new technologies, and so on.  Those who would want all such operations conducted by government agencies need to consider the fact that one of the strengths of American society is its proliferation of vigorous, competent, and useful mediating institutions.  Government power was involved in this case, and many times that is an appropriate outcome, but it was not government by itself that dealt with the problem, but government prompted by the private mediating institution that got the job done. 

 

Fortunately, the issue at hand was not subject to much political pulling and hauling, as neither Republicans nor Democrats wanted to look like they were opposed to helping blind people.  So while a new technology presented a new potential problem to a certain group of people, they noticed it soon enough to deal with it in a way that is not overly burdensome on car makers, and has actually led to a considerable amount of creativity on the part of sound designers.

 

I have not had the opportunity to listen to an EV at low speed to find out if I can hear it coming if I 'm looking the other way, but if I can, I'll have the National Federation for the Blind, the Pedestrian Safety Enhancement Act, and the sound designers working for whatever car company made the car to thank.  And so will you.

 

Sources:  John Seabrook's article "On Alert" appeared on pp. 24-29 of the Aug. 8, 2022 issue of The New Yorker.

Will More Auto Safety Investigators Save More Lives?

Last Friday, the U. S. National Highway Traffic Safety Administration (NHTSA) announced that it was planning to improve the way it keeps tabs on automakers and the safety of their products.  NHTSA administrator Mark Rosekind admitted that the changes were largely inspired by his agency's failure to catch the GM ignition switch problem early enough.  The defective switches on older-model small cars such as the Saturn Ion and the Chevy Cobalt could accidentally cut power to both the engine and the vehicle's airbags, and have been identified as the cause of over 100 deaths and 200 injuries that took place before a massive recall of some 2 million vehicles last year to fix the problem. 

Rosekind acknowledged that although his staff had access to some of the data on the switch problem, they didn't understand that the switch could disable the airbags, and so in two reports issued by the agency, there are calls for improved technological expertise and more investigators in the agency's Office of Defects Investigation (ODI), which currently has about 60 full-time employees.  The report calls for increasing that number to 150, and maybe more.  Rosekind says that NHTSA has already undergone a "culture change" which relies less on the automakers to do self-policing and more on the agency to hold automakers accountable for producing needed data, and also for the agency to do more on-the-ground accident investigation itself.

The question here, as in any change of resources to address a problem with engineering implications, is:  will it do any good?  And will the good that might result be worth the resources expended?

As bureaucracies go, the NHTSA's ODI is pretty small compared to the total number of non-military Federal goverment employees—about 2.7 million people in 2014.  A few million dollars will give the NHTSA all they're asking for and more.  If you asked any of the relatives and friends of those 100 people who died because of defective GM ignition switches about this proposal, they would say the expenditure is worth it if it will save even one life in the future.  And here we get to an issue that tends to come up a lot in discussions of engineering ethics:  the monetary worth of a human life.

I'm not going to waste time playing with dollar/life quotients, because doing that means you have slipped into the never-never land of utilitarianism.  The philosophical approach to happiness called utilitarianism is conveniently (if not entirely accurately) summarized by the phrase "the greatest good for the greatest number."  It has a sneaky kind of appeal to engineering types, because it holds out the (false) promise of reducing complex morally-freighted issues to a straightforward process of mathematical optimization. 

I reject utilitarianism for a number of reasons.  While it has limited usefulness in extreme cases—it tells you, for example, that placing the value of a human life at zero is unwise—the thing usually falls apart well before you can actually sit down with a calculator and do a mathematical operation that will tell you which of several alternatives in an ethical problem is the right one.  It falls apart for me because the very act of putting a dollar value on a human life makes one no different in principle from the slave traders who did exactly that for profit.  It is simply a thing not to be done.

Well, if we can't make the situation into an optimization problem in mathematics, how should we decide if giving the NHTSA more bucks to hire more inspectors is a good idea?  To begin with, a little background might be helpful.

The history of U. S. auto safety has been one of gradual but cumulatively remarkable improvement, starting with the adoption of safety glass in the 1920s by Ford Motor Company, and progressing to seat belts, air bags, and many other safety-related technologies, only some of which were federally mandated.  The result of these improvements has been a pretty steady decline in deaths due to automobile accidents from a high of nearly 3 per 10,000 people per year in the 1930s to about 1 per 10,000 today.  So to begin with, things are getting steadily better, and if self-driving cars realize their early promise, the operator errors and drunk-driving accidents that cause most crashes today may largely go away too.  In the perspective of these numbers, while the 100 or so people who died in the GM switch accidents died needlessly, they were only 0.3% of the 30,000 or so people who died in auto accidents in each of the last few years. 

Ironically, it looks like the public is less upset when a single bad guy can be identified as the cause of a fatal crash, than when the immediate cause is something mechanical like a weak ignition switch spring.  This has nothing to do with mathematical optimizing of resources, and everything to do with how people perceive risk and danger.  You get in your car and tool out on the highway.  Maybe there's a drunk driver out there, but you think you can do something about that.  You can see him weaving around and steer out of his way, for instance.  But some un-thought-of hidden mechanical defect like a defective ignition switch—there's nothing you can do about that.  It's a lot scarier, and the news media know that, and the automakers know that.  Which is why they have been highly motivated to avoid causes of safety recalls, and deeply regret the ones that slip through their own bureaucracies (as the GM ignition switch problem did) and cause only a few verifiable fatalities.

So what is the bottom line here?  I think the bottom line is, there is no bottom line.  This is not an accounting problem.  Maybe three times as many investigators at the NHTSA will make the automakers three times as vigilant to catch the next major safety flaw before it gets built into millions of cars.  While that would be nice, I doubt it will happen, and I don't know of any objective way to tell whether it's happened after it happens, if in fact it does happen.  But the public has read in headlines that the feds are doing something about the problem, and that perception itself, rather than any meaningful actions that may happen afterwards, may have been the main point in this exercise.

Sources:  The Associated Press article on the NHTSA reports was carried by a number of outlets, including the Los Angeles Times under the headline "U. S. auto safety agency admits flaws, starts reform after GM case" at http://www.latimes.com/business/la-fi-hy-nhtsa-gm-20150605-story.html.  I referred to the Wall Street Journal for the statistic on the current (2014) number of Federal employees at http://blogs.wsj.com/economics/2014/11/07/the-federal-government-now-employs-the-fewest-people-since-1966/.  I also referred to the press release of June 5 at the NHTSA website, http://www.nhtsa.gov/About+NHTSA/Press+Releases/2015/nhtsa-forming-new-safety-teams, and the Wikipedia articles "List of motor vehicle deaths in U. S. by year" and "Windshield."  I most recently blogged on the GM ignition switch issue on April 7, 2014 at http://engineeringethicsblog.blogspot.com/2014/04/the-gm-ignition-switch-recall-too.html.