Look, No Hands Google’s self-driving car.

Google's latest tech­nology experiment isn’t about helping you navigate the Web—it’s about teach­ing cars to drive themselves. Exhibiting its usual bound­less faith in technology, the company says it hopes its work leads to cars that are safer and more efficient. The company has logged more than 140,000 miles in seven modified Toyota Pri­uses, along with one modi­fied Audi TT, in self-driving experiments, primarily around the San Francisco Bay area.

The company won’t say how much it’s spending on the project, but it’s clear that the equipment is far from everyday: the cars are loaded with sensors that feed data to an onboard computer that, in turn, controls the vehicle.

A. LIDAR LASER

Mounted on top of the car is a light detec­tion and ranging (LIDAR) laser, a technology commonly used in police speed-detection guns. Like any other LIDAR system, it deter­mines the distance and position of surround­ing objects by sending out laser pulses and measuring how long it takes for the light to bounce back. On the Google cars, the device makes about 10 rotations per second, gath­ering data about objects within a circle of roughly 70 meters.

B. RADAR

Three radar sensors in the front part of the car, and one behind, also help detect nearby objects and determine how close they are.

C. POSITION SENSORS

A sensor on the left rear wheel detects small movements. This data, when combined with information from a GPS system and internal gyroscopes, helps the self-driving car calcu­late which direction it is facing.

D. ONBOARD COMPUTER

A laptop computer inside the car gathers data from the sensors and controls the vehicle through its own onboard computer systems. This makes the steering wheel appear to turn on its own. Data from each driving session is transferred to Google servers for analysis, which is helpful in fixing bugs.

E. VIDEO CAMERA

A video camera placed near the rear­view mirror detects important visual cues such as changing traffic lights.

F. MANUAL CONTROL

The red button instantly restores manual control of the car if the standby driver deems it necessary. A person can also grab control by turning the steering wheel slightly or tapping the brake