Sonoma, California – What Audi calls piloted driving – cars that drive themselves – is rapidly getting closer to the real world. And in this case, ‘rapidly’ means lapping the challenging 4.05 kilometre Sonoma Raceway – better known by its former name, Sears Point – at race pace, lap after lap, without a driver on board. The car in these pictures is Robby, an updated version of the autonomous RS7 that blitzed the Hockenheimring in October 2014 in front of a race day crowd at speeds of up to 240km/h. Robby is about 400kg lighter than its predecessor and has 412kW on tap – never mind who’s driving, this is one quick car. Thomas Muller, Audi’s top boffin for brakes, steering and driver aids, said: “We took the RS7 piloted driving concept to its physical limits at Sonoma, and it posted lap times better than those of sports-car drivers.” How quick? Robby’s ‘personal best’ was a potentially race-winning 2m01.01s – and it could get very close to that, every lap, until the tyres gave out. And the two RS7s are by no means the first: in September 2010 a driverless TTS called Shelley ran the 19.8...