LIDAR

Navigation Aids

Cameras

Ultrasound

Radar

RADAR

MOUNTING BASE

MOTOR HOUSING

LASER RECEIVER

LASER EMITTER

ULTRASOUND SENSOR

GPS UNIT

ACCELEROMETER

CAMERA

WHEEL SENSOR

Google’s autonomous vehicle project uses a spinning range-finding unit, called lidar, on top of the car. It has 64 lasers and receivers.

Used for lane-keeping and back-up assistance. Image-processing software can detect lane stripes, signs, stop lights, road signs and other objects.

Used for adaptive cruise control. Reflected microwaves can identify location and speed — but not always type — of nearby vehicles.

Global positioning system unit determines car’s position. Accelerom- eters and wheel sensors help with naviga- tion when satellite signals are blocked.

Used for assisted parking. Reflected sound waves detect distance to nearby objects. Some cars use short-range radar instead.