Electricity-powered vehicles (also known as EVs) are attempting to break in to the consumer and business market. The infrastructure in many towns is not yet ready to accommodate the charging needs of these types of vehicle, but another concern that may inhibit its attractiveness to consumers is the silent nature of the EV.
Not quite in the way as a friend put it: 'A man likes to hear the roar of his engine', but rather, pedestrian safety is an issue. Unless you have your MP3 player plugged in at full volume, if a car is coming toward you, there is a window in which you can get out of the way.
With a silent EV, however, there is no warning. Sight must be relied upon, and for those that are distracted or have visual impairments, EVs are more dangerous than standard cars -- where you can at least hear the splutter or rev of an engine.
Audi has given this problem its consideration, and is now developing a synthetic engine roar so the company's e-Tron vehicles can be heard by unwary pedestrians.
Audi engineer Rudolf Halbmeir is responsible for the construction of the replica motor sound design. The sound, which will be fitted to all Audi EVs, is not monotonous. Instead, the sound is generated by the millisecond using information gleaned from the car's movements-- including vehicle speed, load and motor speed. The e-Tron then uses a 40-watt loudspeaker attached to the undercarriage to play the electronic sound.
"Out of the building and to the street. A red Audi R8 e-tron pulls up around the corner, purring gently. But when Rudolf Halbmeir taps the gas pedal, the purr turns into a cultivated growl.
Though not unlike an elegant V8, it is especially pure and nuanced, and is shrouded in bright and innovative overtones. The Audi R8 e-tron certainly sounds like a sports car, but also one-of-a-kind and very futuristic."
This artificial and somewhat futuristic sound is loud enough to be heard by nearby pedestrians and cyclists. It may not be great for noise pollution, but it does mean the issue of silent car safety can now be addressed.
For more information, view the video below (Language: German).