California paves way for self-driving cars - Google has modified a Toyota Prius....

California governor Jerry Brown, state senator Alex Padilla and Google co-founder Sergey Brin with a self-driving car at the Google headquarters in Mountain View yesterday. Photograph: Justin Sullivan/Getty ImageSelf-driving cars will soon motor around the most populous US state, at least on a test basis, after a law written with the help of Google was signed by California Governor Jerry Brown.

The law signed yesterday allows trials of autonomous vehicles on the state's roadways as long as there's a licensed human in the driver's seat to take over if needed.

"Today we are looking at science fiction become tomorrow's reality," Mr Brown said at a signing ceremony at Google's headquarters in Mountain View, California.

Google, the operator of the world's largest Internet search engine, has modified a Toyota Prius that drives itself using video cameras, radar sensors, a laser rangefinder and detailed maps. The vehicle includes a failsafe mechanism that lets the driver take control by grabbing the steering wheel or hitting the brakes, much like the override on a cruise control.