The future of motoring: it's automated - In towns and cities

If we want a door-to-door service from our cars, they'll have to work out how to deal with far more complicated roads than motorways, however.

Mueller-Bessler developed a Golf GTI that can steer itself precisely through tight handling courses, but it can't handle the incredibly complex variations of an urban setting.

He says: 'The main problems from my point of view are the technology needed to observe the environment, to interpret the environment correctly, and legislation.'

The Golf would not only have to avoid other cars - some of them, perhaps, still driven by humans - it would have to deal with traffic lights, road signs, junctions and people.

It would have to swerve to avoid a child running out into the road, and be able to tell the difference between a drunk waving his arms around and a workman directing traffic.

Development work continues, however, and this November dozens of teams will enter the Darpa challenge for robotic cars in the US.

Previous versions of the challenge have been run in the desert, with only cactus to run into, but this time around the cars will be competing in an urban environment.

One of the leading teams is from Stanford University, using a Volkswagen Passat called Junior. It's loaded with sensors in a bid to understand what's happening in the world around it and react safely.

Honda's Thomas Brachmann is only too aware of how difficult the challenge will be: 'The traffic environment does not only consist of cars but also pedestrians, trams and motorcycles.

'Preparing a car for all eventualities is extremely difficult.'