An Audi A7 has driven itself over 550-miles from San Francisco all the way to CES 2015 in Las Vegas.

Audi says that the self-driving A7 has sensors that it claims are now "production ready". Despite being a futuristic car the sensors aren't all new with the long-range forward radar the same as the one found in the current A7 for adaptive cruise control.

But this also has two side and rear sensors and a LIDAR laser scanner in the grille to recognise objects. And if all that wasn't safe enough there's a 3D camera and four smaller cameras to monitor front a rear views from the corners of the car too.

All these sensors feed into a computer in the car which then controls acceleration, breaking and even steering. And before you start talking about it only working at low speeds, this works from 0-70mph. But there is indeed a caveat, once in urban areas the driver needs to take control. So ideal for US highway driving but not so great for city slickers.

The Tesla Model S has a similar system in place which basically does the same thing. But Audi says this is far from the final model and suggests we can look forward to a fully self-driving car, in all environments, in a few years.

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