The light sensitivity of modern digital cameras has increased significantly in recent years, but their performance in low light at night still is limited. The headlights help somewhat, but their light distribution and the elements that prevent the blinding of oncoming drivers restrict how well they can illuminate the road for the camera.

Therefore, another technology comes into play here: additional illumination with invisible infrared light. Lamps with infrared emitters based on LED technology will not blind anyone. Conventional CMOS (complementary metal-oxide-semiconductor) cameras can detect this near infrared light well and therefore capture a scene even at night with good contrast and range.

Radar provides precise data on cars up ahead at a fairly great distance. In city traffic or stop-and-go situations, however, the information it provides becomes inaccurate. This problem can be solved by a LIDAR system, which and functions like radar (radio detection and ranging) except that it uses laser light.

A LIDAR system measures the distance from objects and their speed by time-of-flight measurement of the laser pulses. To obtain more detailed information on the surroundings, a camera with a strong infrared light source (headlight) can be used to detect and classify objects in the vicinity of the vehicle without blinding oncoming traffic.

If an analysis of the collected data clearly indicates a dangerous situation, the system first gives the driver a warning, which can be a loud tone or an optical warning visualized in the front windshield. However, the warning presupposes the person behind the wheel still has time to intervene. If this no longer is possible because of reaction times, automatic emergency braking can follow.

Sometimes, even the best monitoring systems and the strongest brakes cannot prevent an accident from happening. In such cases however, these systems do help minimize the severity. The lower the impact speed, the less serious the damage and the lower the risk to passengers. For their protection, the safety belts can be pre-tensioned prior to impact and the seats moved into optimum position. Another option is to adapt the control of airbag release to the situation.

But it is not only the passengers inside a car who have a safety advantage from the thorough observation of what is going on in front of the car. The first cars with pedestrian airbags are now appearing on the market. They must only trigger when the system determines a person will hit the hood – and then only with absolute certainty.