Nissan has solved the problem of overly-quiet electric vehicles. The new technology will make its debut in the LEAF when it arrives in Ireland in February 2011.
Nissan has developed a set of distinctive sounds that will come standard in the Nissan LEAF.
Nissan worked with the visually impaired and studied the work of cognitive and acoustic psychologists before coming up with the snappy title of the 'Approaching Vehicle Sound for Pedestrians' system.
The sine-wave sound system sweeps from 2.5kHz at the high end to a low of 600Hz, which is apparently an easily audible range across age groups. Nissan worked to avoid a sound range that would add unnecessary noise to the environment (around 1,000Hz).
Depending on the speed and status of the LEAF, the sound system will make sweeping, high-to-low sounds. When the car is starting, the sound will be louder, so a visually impaired person would be aware that a nearby car was starting up.
When the car is in reverse, the system will generate an intermittent sound. The system will not emit noise over 30km/h. It is all controlled through a computer and synthesizer in the dash panel, and the sound is delivered through a speaker in the engine compartment. A switch inside the vehicle can turn off these sounds.
At a demonstration of the technology in Japan, CompleteCar.ie experienced this first hand. We were asked to face the opposite direction of firstly a Tiida coming at us and then a LEAF. In both cases, we noticed the cars at the same time. The noise from the LEAF is not loud, but it reaches a pitch that triggers your awareness.