Automatic Braking Systems

Basic Description

A study conducted by the German Association of Insurance revealed that 50% of rear-end collisions occur without any braking and as much 70% percent occur with braking that is insufficient to stop the vehicle in time. Furthermore, nearly 75% of all accidents that result in injuries happen within city limits at speeds below 20 mph. Active braking systems are well suited for avoiding or minimizing the damage caused by accidents under these conditions.

Active braking systems monitor conditions ahead of the vehicle. If a crash appears to be imminent, these systems will automatically apply an appropriate braking pressure. Continental’s Emergency Brake Assist system, for example, uses three laser beams level with the rearview mirror to scan the road for obstacles up to eight meters ahead. The system is capable of preventing collisions if the speed differential between the two vehicles is less than 10 mph. At speeds greater than 10 mph, the system can reduce the severity of impact.

In 2010 Volvo will be implementing a new dual-mode detection technology that will be capable of detecting pedestrians as well as other vehicles and applying full break pressure. The system will use both radar located behind the rearview mirror and high resolution cameras for image detection. The combination of the two sensing technologies will enable the system to more accurately asses the situation to further aid in accident prevention.

Sensors

Headway sensor (radar), image sensor, vehicle speed sensor, accelerator pedal position, brake pedal position

Actuators

brakes, warning display

Data Communications

Control Unit Communication: Typically Control Area Network (CAN) Bus System

Manufacturers

Continental, Volvo

For More Information

[1] Volvo ready to bring cars to a full stop in an emergency - without any help from the driver, USA Today, Sep. 28, 2009.

[2] Volvo - Auto Brake, YouTube, Sep. 2008.

[3] Volvo Previews New Generation Collision Warning System, YouTube, June 2006.