Distronic Plus and Brake Assist Plus Reduce Rear-end collisions by 20%

Muamer Hodzic June 10, 2008

Distronic Plus and Brake Assist Plus, the Mercedes-Benz assistance systems based on sophisticated German engineered radar technology, are proving to be effective contributors to accident prevention. This is the conclusion reached after an analysis carried out by Mercedes-Benz on the basis of representative accident research data. With the help of this technology an average of one fifth of all rear-end collisions could be prevented in Germany alone. And on motorways, rear-end collisions could be reduced even further: by an average of 36%. The Mercedes-Benz systems warn drivers when they are maintaining too little distance from the vehicle traveling in front and provide support in the event of emergency braking.

Press Release

Engineers working for the Stuttgart-based car manufacturer have developed a procedure which for the first time makes possible a predictive calculation of the usefulness of new safety technologies. For this the specialists have taken into account both official statistics and the analysis of the approximately 16,000 traffic accidents which have so far been studied within the framework GIDAS (German In-Depth Accident Study).

The evaluation of the safety potential offered by the DISTRONIC PLUS and Brake Assist PLUS assistance systems is based on the reconstruction of more than 800 rear-end collisions. The focus of the representative study was the question: how many of those accidents could have been avoided if all the passenger cars had been equipped with this Mercedes-Benz technology?

The results confirmed the great safety effect of the systems: with DISTRONIC PLUS and Brake Assist PLUS an average of more than 20 percent of all rear-end collisions could be prevented. In a further one-quarter of all collisions the systems could contribute to a significant reduction of the severity of the accident.

The greatest safety potential is offered by the interaction of modern radar and braking technology on motorways, where around 36 percent of all rear-end collisions could be avoided.

Around 40 percent of all S-Class saloons equipped with radar technology

The DISTRONIC PLUS proximity control system keeps your vehicle at a previously chosen distance from the vehicle travelling in front and, if necessary brakes your vehicle to a complete standstill, depending on the traffic situation. If the distance to the preceding vehicle narrows down too rapidly, the system warns the driver and calculates the required brake pressure, which is then provided instantaneously by the Brake Assist PLUS system as soon as the brake pedal is depressed. Should the driver disregard the warning, the PRE-SAFE® Brake system performs an emergency partial braking manoeuvre, significantly reducing the severity of the impact.

Since 2005, Mercedes-Benz has offered these radar-based assistance systems for the S-Class, and since 2006 for the CL luxury coupe. Around 40 percent of all German customers buying new S-Class vehicles equip them with this safety technology; while the proportion of CL-Class outfitted with DISTRONIC PLUSand Brake Assist PLUSis even higher, exceeding 80 percent. Since 2005 Mercedes-Benz has delivered a total of more than 45,000 passenger cars featuring these innovative systems.

In order to calculate the safety benefits provided by this technology, Mercedes-Benz specialists make use of relevant data from the individual accidents, such as speed, distance to the other vehicle and driver’s braking behaviour. With these data, together with the governing algorithms of DISTRONIC PLUS and Brake Assist PLUS, the individual speed reduction is calculated. The engineers from Mercedes-Benz decided to apply a conservative calculation principle and did not take into account, for example, the additional safety-enhancing effect of the visual and audible distance warnings which prompt the driver to apply the brakes himself if the system determines it can no longer avoid a collision by itself. The analysis is based on the assumption that the drivers ignore these warnings.

In Germany there are over 50,000 severe rear-end collisions every year, causing death or serious injuries to around 5,700 people. Of all the accidents involving personal injury, one in six is a rear-end collision. In the United States this accident type makes up around 30 percent of all serious traffic accidents.

The engineers of the Stuttgart-based car manufacturer continue to work tirelessly on the development of further driver assistance systems aimed at helping to prevent road accidents.