FIXING THE EQUATION:

As millions of cars are under recall for potentially lethal air bags, designers are trying to reduce the need for the device -- using sensors, radar, cameras and lasers to prevent collisions in the first place.

With driver error blamed for over 90% of road accidents, the thinking is it would be better to have them do less of the driving. The US-based Insurance Institute for Highway Safety found that forward-collision warning systems cut vehicle-to-vehicle crashes by 7% -- not a quantum leap, but a potential life saver. Nearly 31,000 people died in car accidents in 2012 in the United States alone.

"Passive safety features will stay important, and we need them. The next level is now visible. Autonomous driving for us is clearly a strategy to realise our vision for accident-free driving," said Thomas Weber, global R&D head at Mercedes-Benz .

While giving a computer full control of a car is some way off, there's a lot it can do in the meantime.

For now, in some cars you can take your foot off the pedal and hands off the wheel in slow-moving traffic, and the car will keep pace with the vehicle in front; it can jolt you awake if it senses you're nodding off; alert you if you're crossing into another lane; and brake automatically if you don't react to warnings of a hazard ahead.

How close this all comes to leaving the driver out of the equation was illustrated by an experiment at Daimler last year: adding just a few off-the-shelf components to an S-class Mercedes, a team went on a 100 km ride in Germany without human intervention. "The project was about showing how far you can go, not just with fancy lasers, but with stuff you can buy off the shelf," said David Pfeiffer, one of the team.

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