Testing the car that drives itself

Want to be chauffeured home by a self-driving car? We’ve taken it for a road test.

I’ve just done a lap of Silicon Valley in a self-driving car so secret we had to leave our camera phones behind. No photos or video allowed: only these carefully selected hand-out shots.

With two trained technicians in the front seat of this Mercedes-Benz development vehicle we did a 15 minute loop not far from Apple headquarters.

The inside of the car appears normal except for the extra cameras on the dashboard and in the windscreen, the giant computer screens giving a detailed view of the system at work, and the loud whirring of a massive computer stashed in the centre console.

After the press of a button, the driver took his hands off the steering wheel and the car took control. Literally.

Eight radar sensors and five cameras help it spot other cars, traffic lights and stop signs.

The GPS navigation tells the car what the speed limit is, and the automated driving system does the rest from there, including braking, steering and accelerating.

The technology is still in the early stages of development, so at times the brakes are bit sudden and it feels like you’re being driven by a taxi driver with a heavy foot.

The steering isn’t as smooth as a human’s touch, but for a first effort it’s impressive.

The only time the system got tricked was when we merged onto a freeway on-ramp. Two lanes merged into one, and a car in the other lane sped up to overtake, so our car hit the brakes.

The only time the system got tricked was when we merged onto a freeway on-ramp.

We could have been rear-ended but the car decided that stopping was the best option.

Besides, our trained driver was ready to take evasive action if needed.

But when it came to merging from the ramp and onto the freeway proper, it did a better job that most Saturday morning drivers.

The next step: getting the technology to learn who has right of way at four-way intersection.

But make no mistake: the technology to create the automated car is close to reality, due in showrooms by 2020.

But will it be legal by then? No-one knows.

The most likely scenario: it will still be the driver’s responsibility to avoid a crash and not break the law. And that includes drink driving. You’ll still need to be under 0.05 even if you own an autonomous car.

To end any arguments before they may arise, Mercedes also plans to have cameras with a 360-degree view record the last 30 seconds before a crash.