The technical highlights of the new Mercedes B-Class: Radar-based collision warning system - A new milestone in safety technology


Detailed analysis by Mercedes-Benz's in-house accident research department indicates that almost half of all rear-end collisions could be avoided or the severity of such accidents reduced with the aid of radar-based safety systems such as COLLISION PREVENTION ASSIST and adaptive Brake Assist. This analysis drew on the experience acquired with the Mercedes innovations DISTRONIC PLUS and BAS PLUS. The company is now claiming the role of innovation leader in the compact segment, too, and will be introducing a radar-based collision warning system with adaptive Brake Assist in the new B-Class in the course of this year. In contrast to systems currently on the market in this class, the new Brake Assist feature is not merely a system intended to minimise minor damage in urban traffic. Rather, this innovative solution is aimed at protecting motorists from typical rear-end collisions in all traffic situations.


New Brake Assist system: world premiere in the compact class

This year will witness the next milestone in the democratisation of automotive safety technology: the new B-Class from Mercedes-Benz will be the first car worldwide in the compact segment to offer radar-based collision warning with adaptive Brake Assist as standard. The company expects the introduction of this technology to have a significant positive effect on accident statistics.
This expectation is backed up by test results: during tests with 110 car drivers in the driving simulator, the accident rate in three typical situations fell from 44 to eleven percent thanks to a combination of COLLISION PREVENTION ASSIST and adaptive Brake Assist.

The new assistance system fits the bill perfectly here: it gives a visual and acoustic warning to alert a possibly distracted driver and prepares Brake Assist for the most precise possible braking response. This is initiated as soon as the driver emphatically operates the brake pedal.

Key functions of the coming generation

Radar-based COLLISION PREVENTION ASSIST with adaptive Brake Assist

- recognises an inadequate distance from a vehicle ahead in the speed range between 30 and 250 km/h,
- recognises when the gap is decreasing. In case of an imminent danger of collision, the driver is provided with a visual and acoustic warning,
- is able to recognise stationary objects ahead of the vehicle and output corresponding warnings,
- recognises specific driving situations such as bumper-to-bumper traffic and adapts the activation threshold for the warning and adaptive Brake Assist accordingly,
- calculates the precise braking force ideally needed to avoid an accident when a danger of a collision is detected and makes best possible use of any distance remaining. This means that the driver behind also has better chances of preventing a rear-end collision.
- The brake pressure is adjusted if the situation changes – if the vehicle ahead accelerates, it is decreased to the level the driver requires; if the distance to moving and stopping vehicles decreases, the brake pressure is increased further.
- Preventive safety systems (PRE-SAFE®) can be activated as necessary (e.g. belt tensioners).
- The new system meets the key "Forward Collision Warning" requirements of the NHTSA, the American road and vehicle safety authority.


In Germany rear-end collisions are still responsible for 22 percent of accidents involving injury or fatalities, and in the USA the figure is as high as 31 percent. Mercedes-Benz has been working on methods to prevent such accidents for many decades now. Milestones of the company's safety developments include ABS (1978), Brake Assist BAS (1996), DISTRONIC proximity control (1998) and the further development stage DISTRONIC PLUS with BAS PLUS (2005). These new systems were always premiered in the luxury class models, but in the interests of traffic safety it has always been a principle of Mercedes-Benz to make innovative technology available on a broad basis as rapidly as possible – also outside its own model range. As a result ABS and BAS, and incidentally also the Mercedes development ESP®, are nowadays standard equipment in practically all automobiles.

Source: Daimler AG

Copyright © 2011, Mercedes-Benz-Blog. All rights reserved.