To address the safety issues posed by the relatively silent nature of electric vehicles (EV), U.S. and Japanese transportation agencies are considering requiring automakers to come up with sound producing devices to warn pedestrians and other motorists of their approach.
Organizations including advocacy groups for the visually impaired have raised concerns in recent months, and this past summer the Japanese Transportation Ministry convened a 13 member panel to study the matter and recommend possible solutions. The panel is expected to release its findings on December 31.
Toshiyuki Tabata, a Nissan engineer who has spent the last 30 years devising methods for making vehicles quieter, sees the irony in the situation. “We fought for so long to get rid of that noisy engine sound,” says Tabata, who has enlisted the aid of music composers in his quest for an effective sound for electric-powered vehicles to produce.
As they move toward greener, quieter vehicles, both Nissan and Toyota Motor Corporation are racing to develop both the sound and the means of producing it. Nissan is slated to unveil its new Leaf electric vehicle in Japan, Europe and the U.S. next year. General Motors Company has set November of 2010 as its target date to launch the Chevy Volt plug-in electric vehicle, and Toyota plans to debut its own line of battery-powered cars by 2012.
Tabata said that his years of working to eliminate engine sound caused him to recoil at the suggestion of making cars noisier. The idea of simply artificially generating the sound of a combustion engine was immediately dismissed. Tabata said, “We wanted something a bit different, something closer to the world of art.”
In their quest for the perfect sound, Tabata and his team came up with a high-pitched sound similar to that made by flying vehicles featured in the 1982 cult classic film “Blade Runner”.
He said, “We decided that if we’re going to do this, if we have to make sound, then we’re going to make it beautiful and futuristic.”
In addition to eliminating the caustic emissions, the silent running nature of electric vehicles reduces another problem created by combustion engines; noise pollution. Since their lack of engine noise is only a concern in certain situations where pedestrians might be present, a compromise is proposed by which EVs would emit sound when the vehicles are stared and automatically shut off once the vehicle reached a speed of 12 mph according to Tabata. At higher speeds, EVs naturally generate tire noise. Gas-electric hybrid models also generate engine noise at higher driving speeds as they switch from electric power to the conventional combustion method of propulsion.
Suzuki Takayuki, a spokesman for the Japan Federation of the Blind, concedes that there are no documented cases of pedestrians being seriously injured as the result of not hearing an approaching EV. However, Takayuki, who is visually impaired, says that a hybrid once ran over his cane as he was crossing a street in Tokyo. He says, “This isn’t just an issue for the blind. There’s also a danger to children and the elderly.”
In the U.S., Elly Martin, spokeswoman for the National Highway Traffic Safety Administration, said that the agency is analyzing information on accidents involving hybrid vehicles and pedestrians. The investigation was initiated in response to requests by a number of groups, including the National Federation of the Blind, to require automakers to include sound emitting devices in their hybrid and EV designs. On September 3, Nissan demonstrated its sound producing system to the NHTSA. The agency expects to publish its final report next January.
Some automotive electronics manufacturers are also attempting to come up with a solution to the problem. Japanese-based, Datasystem Company has devised a system that produces 16 different sounds, presumably to be used in different situations. Among the sounds are a “meow”, a cartoonish “boing” sound and a human voice that repeats a variety of phrases including “excuse me”. The system is currently available and sells for 12,800 yen (about $140).
Tabata says, “There is a risk of these things sprouting up like bamboo shoots everywhere and disrupting the general noise environment.” He says that, although no standardized regulations have been agreed to, Nissan may move to implement its solution before the launch of its new Leaf EV.
At this point, the question is whether the addition of sound would be a selling point or a deterrent. Tabata says, “We don’t want to destroy the brand of the electric car. We want to have something that will enhance its image.”