Technology sometimes can be like a Broadway play—a good concept that may need a bit of out-of-town tinkering before it becomes a success. That is likely the case with autonomous vehicles: cars or trucks that can sense and navigate their environment without human drivers required.
In 2011, Nevada was the first state to pass a law concerning the operation of autonomous cars. Last fall, California followed suit when Gov. Jerry Brown signed a law that allows self-driving cars on public roads. Brown rode to the signing ceremony at Google’s headquarters in the passenger seat of a Toyota Prius modified by Google to be able to drive itself. As of this writing Google’s fleet of fully autonomous Toyota Prius hybrids have logged more than 300,000 miles.
A Google engineer sat in the driver’s seat in the car with Gov. Brown (the California law requires that a driver be present to take control of the vehicle when needed) to monitor the car’s performance, as the nascent technology still needs drivers to deal with unexpected obstacles or events such as when a car shreds a tire on the highway. 

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