There has been some talks regarding placing some synthetic sound emitting gadgets in the vehicles, in order to help blind pedestrians. A number of pedestrians are though worried that that the silent low speed vehicles if pass by them, then they would not be able to hear them.

In the previous week, Nissan made an announcement that a pedestrian safety sound system for its upcoming Leaf electric car will be introduced. The sound system comprises of a speaker under the hood and a synthesizer in the dash.

The driver will be able to turn it off, but it comes on by default at start-up. At speeds above 30km/h, the system on its own turns itself off as natural road noise at these speeds is faultlessly easy to hear by the pedestrians.

The sound, a sine wave sweeping from 2.5 kHz to 600Hz, was designed to be easy to hear by all age groups. At set up, the sound comes on at its loudest to caution the visually challenged and other pedestrians that a car is on the verge of entering their surrounding area. When the Leaf is reversing, the system makes a blinking sound, which is similar to the back-up warning systems on trucks and vans.