DISTRONIC PLUS and Brake Assist PLUS – Mercedes assistance systems based on sophisticated radar technology – are highly effective at helping to prevent accidents. This is one of the findings of an analysis carried out by Mercedes-Benz based on representative accident-research data. This technology can prevent a fifth of all head-to-tail crashes in Germany alone. On motorways, the accident rate can be reduced by as much as around 36 percent. Mercedes-Benz has further enhanced the radar technology for the new E-Class and the model year 2009 S-Class.
Every year in Germany there are over 50,000 serious head-to-tail crashes, in which some 5700 people are either killed or seriously injured. One in six traffic accidents in which people are injured is down to a head-to-tail crash. The situation is even more serious in the US, where this type of collision accounts for around 30 percent of all serious road accidents.
In developing the DISTRONIC PLUS and Brake Assist PLUSradar-based assistance systems, which have been available for the S-Class since 2005 and the CL-Class since 2006, Mercedes-Benz has made an important contribution towards preventing head-to-tail crashes. This is one of the findings of the latest accident research carried out at Mercedes, based on the reconstruction of over 800 head-to-tail crashes. The representative study focussed on one question in particular: how many accidents of this type could be prevented if all passenger cars were equipped with this Mercedes technology?
The results confirm the considerable safety-enhancing effect of the assistance systems: DISTRONIC PLUS and Brake Assist PLUS prevent over 20 percent of head-to-tail crashes on average. In another quarter of these collisions, the systems can help to greatly reduce accident severity. This combination of state-of-the-art radar and brake technology offers the greatest safety potential on motorways, where around 36 percent of all head-to-tail crashes can be prevented.
Warns and assists the driver as well as providing emergency braking
DISTRONIC PLUS proximity control operates at speeds of between 0 and 200 km/h: it keeps the car a set distance behind the vehicle in front, applies the brakes as required and can even bring the car to a complete halt, depending on the traffic situation. If the gap to the vehicle in front narrows too quickly, the system gives the driver an audible warning and, as soon as this first warning signal sounds, automatically calculates the brake pressure required to prevent
a collision in this situation.
This technology helps the driver to gauge the level of risk and makes the calculated brake boosting force available instantly, even if the driver does not press the brake pedal forcefully enough. Brake Assist PLUS allows controlled, targeted braking and, if necessary, increases the braking force right up to the point at which an emergency stop is performed, depending on the road speed and the distance to the vehicle in front.
New radar sensor with extended range and medium-range detection
When a potential accident situation is recognised, assistance is provided courtesy of two short-range radar sensors behind the front bumper and a long-range radar in the radiator grille. Mercedes-Benz has further enhanced the performance capability of these sensors. In the new E-Class and model year 2009 S-Class, Mercedes-Benz uses a newly developed sensor with a range of 200 metres – instead of 150 metres, as previously – for the long-range radar. In addition, the sensor now also has medium-range detection capability, allowing monitoring of the area up to around 60 metres ahead of the car with a 60-degree beam width. This new technology enables even more precise monitoring of the traffic situation in front of the car and even better detection of dynamic events such as a car in front swerving suddenly. The two wide-beam short-range radar sensors (80‑degree beam width) with a range of around 30 metres are still employed.
40 percent of all S-Class saloons are equipped with radar
Mercedes-Benz offers DISTRONIC PLUS in combination with Brake Assist PLUS as an optional extra. Around 40 percent of customers buying new S-Class models in Germany specify this safety technology; in the case of the CL-Class, over 70 percent of customers order DISTRONIC PLUS and Brake Assist PLUS. Since 2005, Mercedes-Benz has supplied customers with over 50,000 cars featuring these innovative systems.