Continental to employ stereo vision for driver assistance systems

May 04, 2011 // By Christoph Hammerschmidt
Automotive supplier Continental AG has announced to add a stereo camera to its ContiGuard safety system as an integral element of its forward looking braking systems. This will help prevent or at least reduce the seriousness of the frequent accidents involving pedestrians or with vehicles at intersections, the company said.

Car accidents in which pedestrians are involved make up almost half of traffic accidents resulting in major personal injury. Since the stereo camera has two 'eyes', it is able to use the difference in the images within one camera shot to detect every type of obstacle, from loads that have fallen onto the road to people and animals, and can determine their size and the distance to them. This cannot be done sufficiently reliably with mono-cameras, which also have to be taught to recognize a car or a motorcycle and which are then only able to identify objects that they have learned.

“Since the stereo camera also realizes the already familiar assistance systems, such as Lane Departure Warning, Traffic Sign Recognition, and Intelligent Headlamp Control, we think that it will set a new trend in the medium to long term and will be available for all vehicle categories, from compact cars to premium vehicles”, said Andreas Brand, Head of Passive Safety & ADAS Business Unit at Continental's Chassis & Safety Division.

The stereo camera consists of two high-resolution CMOS mono-cameras, housed approximately 20 centimeters apart behind the windshield. Whereas a mono-camera only estimates distances, the stereo camera measures the distance to an object and its height from the road surface. Thus, the stereo camera’s analyzing electronics exploit the same effect that gives humans spatial vision, i.e. the parallax shift between two images.

At medium distances of 20 to 30 meters, the stereo camera can determine the range to the object with an accuracy of between 20 and 30 centimeters. It retains its high resolution capability even under difficult circumstances in which other technologies for object recognition might reach their limits; for example, when several objects are in close proximity to each other, when objects are partially obscured, or when there is poor contrast between the object and its background. The fundamental strength of the stereo camera is its ability to