An automated adventure at the wheel of a driverless BMW

We're doing 130kph on the inside lane of a wide motorway near Munich, Germany, and I can see the rear of a large lorry looming in the middle distance. Normally, I'd check the mirrors, signal and move out to overtake in plenty of time before slipping back in front of the slower traffic. Today, however, both my hands are behind my head and my feet are lying flat on the floor in front of me. Is disaster imminent? No, the car calmly does the indicating, blind spot checking and lane changing for me so I can relax. This could be the future if BMW has its way; this is a driverless car and we're on a public road. Driverless cars have been the stuff of science fiction for years. Herbie, KITT, the Batmobile - they've all captivated audiences with their ability to hit the road by themselves. Ironically, it was the Bond film Tomorrow Never Dies that spawned a not totally driverless but at least remote-controlled BMW 750i, and now the same car manufacturer has developed a pair of driverless 5 Series saloons.The German firm isn't the only manufacturer to take on a self-driving car. Volkswagen has a Passat estate with a "temporary autopilot" function, and perhaps better known is Google's driverless car project, which was doing rather well until it crashed in California - supposedly due to human error, rather than a mechanical hiccup. BMW arguably has the most complete and usable version of the technology yet. Save for the big ConnectedDrive decals along the sides, you wouldn't know the difference between this car and a standard 5 Series. Look closer, though, and the minute differences become apparent. The exterior is adorned with small sensors, cameras and a few more aerials than usual. There are a couple of square sections missing in the front bumper, and one at the rear housing a similarly innocuous black rectangle. In total, there are 12 sensors, each of which sends messages to a colossal amount of computer equipment in the boot - so golf club space is out of the question. They, in turn, talk to a highly advanced GPS system and next-generation versions of BMW's active cruise control and lane marking detection systems. All that technology allows it to travel with pinpoint accuracy and avoid other traffic, though the driver can override the system at any time by braking, accelerating or steering, similar to conventional cruise control."We began looking into this six years ago," says BMW's project director, Professor Raymond Freymann. "We made the first cars drive around race tracks, but travelling around a circuit at 50kph is not very sexy." At this stage the project was known as TrackTrainer and engineers programmed the car to follow the best line on a circuit (as previously set by human racing drivers) to guarantee a perfect run every time. This progressed to high-speed runs, much to Prof Freymann's delight: "Three months ago we went around the Laguna Seca with the technology in a 335i. We were driving [automatically] on the limits all the time and no one could keep up with us." Consistently brilliant laps do not make for entertaining racing, though, so the project was taken to the open road. BMW chose the 5 Series for the road variant because, when the project started, it had more existing sensors for the likes of assisted parking and active cruise control so it required less retro-fitting of electric gadgetry than any other model in the range. Save for the lack of a boot, it's a pretty conventional 5 Series interior. The one obvious change inside is the addition of a large monitor on the dash. It sits on the passenger side corner of the centre console, angled slightly towards the driver, and displays what looks like an archaic computer game from the 1980s. But looks can be deceiving - along with images from the front and rear cameras, a series of blue blocks of varying sizes regularly pop up and move longitudinally down the screen. These represent the vehicles around the car on the road - longer ones for lorries, shorter ones for cars, giving you an idea of just how clever the technology is.