Google declined to comment.
Absmeier was a passenger in a prototype Audi Q5 crossover vehicle equipped with lasers, radar, cameras and special computer software designed to enable the vehicle to drive itself, with a person at the wheel as a backup.
As the Delphi vehicle prepared to change lanes, a Google self-driving prototype—a Lexus RX400h crossover fitted with similar hardware and software—cut off the Audi, forcing it to abort the lane change, Absmeier said.
The Delphi car "took appropriate action," according to Absmeier.
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Delphi's Silicon Valley lab is based in Mountain View, not far from Google headquarters. While Delphi is running two Audi prototypes in California, Google has been testing more than 20 Lexus prototypes.