A vibrating accelerator pedal that tells motorists when to slow down could save them a substantial amount of money in fuel bills.

Most drivers waste fuel by braking for traffic lights or other obstacles only at the last minute, but expert drivers see that they will need to slow down and take their foot off the throttle much sooner.

The vibrating pedal is part of a prototype system that mimics this approach by monitoring traffic, speed restrictions, junctions coming up and so on, and then telling drivers to ease off the gas.

The principle is simple. If your car is travelling at, say, 80 kilometres per hour, it burns more fuel per kilometre than if it is travelling at 50 kph. So if you know you have to slow down from 80 to 50 kph in perhaps 300 metres, you may as well decelerate straight away and drop to the lower fuel-consumption rate.

More here.