You think your commute is bad? Google’s self-driving cars are doing 3 million miles every day, according to the company’s January report.

As it stands, the cars have clocked up more than 1 million miles driving autonomously on public roads, but using simulators, the vehicles are racking up 3 million miles daily.

That’s the equivalent of circling the equator 120 times a day, made possible by the processing power of Google’s enormous data centers.

If there’s any sort of update being rolled out that could alter the car’s performance, each vehicle re-drives every mile it’s done on real roads via the simulator before to see how it reacts to the changes.

It’s not all simulation, though, the cars are still doing between 10,000 and 15,000 miles per week on public roads. Google then uses playback of the drivers’ actions to predict what scenarios could have happened if the car had been self-driving and uses that to make refinements to its software.

When test drivers are simulating accidents, Google’s engineers use that scenario to identify deficiencies and see how the car would react on its own.

Google’s self-driving car fleet, 22 Lexus SUVs and 33 prototypes, are divided between Mountain View, California and Austin, Texas. One of the reasons Austin was chosen as a secondary location was because of its horizontal traffic lights, which Google is now gathering data on.

The company manually drives every location before programming the cars to autonomously navigate the streets, so the smallest differences, like traffic lights, lane lines or ever curb heights, need to be analyzed to ensure that the car’s sensors can be calibrated to suit.

Google will need to do this for every city it intends to make the vehicles available in, so it might be a while before we can take our hands off the wheel.

➤ Google Self-Driving Car Project Monthly Report [Google]

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