Google’s fleet of robotic Toyota Priuses has now logged more than 190,000 miles (about 300,000 km), driving in city traffic, busy highways, and mountainous roads with only occasional human intervention. Their driverless car technology could change transportation in the near future. (Nevada recently became the first U.S. state to make self-driving cars legal.)
Stanford University professor Sebastian Thrun, who guides the project for Google, described how it works in a keynote speech at the IEEE International Conference on Intelligent Robots and Systems in San Francisco last month.
The “heart of the system” is a laser range finder mounted on the roof of the car. The device, a Velodyne 64-beam laser, generates a detailed 3D map of the environment. The car then combines the laser measurements with high-resolution maps, producing different types of data models that allow it to drive itself while avoiding obstacles and respecting traffic laws.
Before sending the self-driving car on a road test, Google engineers drive along the route one or more times to gather data about the environment. When it’s the autonomous vehicle’s turn to drive itself, it compares the data it is acquiring to the previously recorded data, an approach that is useful to differentiate pedestrians from stationary objects like poles and mailboxes.