An ultra-precise GPS is a technological keystone for autonomous cars. Tough to execute with satellite data alone, it needs to be physically mapped. GM realized most of their cars are already fitted with cameras, and is turning them on to cartography with partner Mobileye.

“Cameras are the most natural sensors for creating maps because they are already available in most new car models as part of the trend toward growing driver assistance deployment,” said Amnon Shashua, co-founder, chairman and chief technical officer of Mobileye in a . “Creating and updating maps using on-board camera technology supplies the missing link between on-board sensing and the requirement for full redundancy to enable safe autonomous driving.”

So basically your Chevy’s OnStar will beam landmarks and road information to a server at about 6 kilobytes per mile. For non-nerds reference; a song on your iPhone is about 3,0000 kilobytes. The image of the Chevy Volt at the top of this post is around 150 kilobytes. Still intangible and irrelevant? Well, I tried.

Mobileye is saying that this mapping method will boost accuracy to about 10 centimeters versus the GPS in your current car, which we’re told is more often close to “within 10 meters” of accuracy.

10 centimeters is still enough to dodge or ram an obstacle, but it’s a heck of a lot better than 10 meters which is about the length of two F-150s.

This is pretty much exactly what . If every automaker got onboard, and then pooled data I bet we’d have some razor-sharp roadmapping. And a data center that’s logged with the driving habits of just about everyone in America.

Start polishing those tin foil hats! Or welcome your new automotive overlords. We’ll see how long it takes for GM to get the data they need for their future cars to drive themselves, maybe we’ll be ready to hand off the steering wheel by then.

Image via GM

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