Cycle & Carriage - The SLK-Class Roadster

The integrated safety concept from Mercedes-Benz

Virtually no other area inspires the Mercedes-Benz engineers to produce such consistently impressive results as much as research into new safety technologies. The first important safety milestone was reached back in the 1950s with the development of the passenger safety cell, invented by Béla Barényi. Today it is just one of many components of the integral safety concept which edges us ever closer to our vision of accident-free driving.

Phase 1: Safe driving

For safe driving, the Mercedes-Benz safety concept supports you using many different measures: the control and display system is especially tailored to the driver. Then there are systems which are designed to alert and assist the driver in critical situations.

DISTRONIC PLUS proximity-controlled cruise control including PRE-SAFE® brake (optional) DISTRONIC PLUS proximity control helps the driver to maintain a specified (timed) distance from the vehicle in front when travelling at speeds of 0 to 200 km/h. Implementing BAS PLUS Brake Assist in conjunction with the PRE-SAFE® brake system helps to avoid rear-end collisions more effectively. If radar sensors identify a potential collision hazard and the driver applies the brakes, BAS PLUS is primed to apply a braking pressure in accordance with the situation. If a potential collision hazard is identified within the speed range 30 to 200 km/h and the driver fails to apply the brakes in good time, the PRE-SAFE® brake system emits visual and audible signals. If the driver does not respond to this warning, independent partial braking is activated approx. 1.6 seconds before the calculated impact at a deceleration rate of up to 4m/s2. If the system categorises the situation as highly critical and there is still no reaction from the driver, an independent full brake application can be initiated automatically 0.6 seconds before what is considered an unavoidable impact.
Adaptive brake lights The adaptive brake lights warn following traffic that emergency braking is taking place. If the driver makes an emergency stop from a speed greater than 50 km/h, the brake lights flash in order to warn following traffic. If the vehicle comes to a stop from a speed greater than 70 km/h, the hazard warning lamps are switched on automatically. In the event of emergency braking the adaptive brake light function warns following traffic by flashing the brake lights during the braking process.
ATTENTION ASSIST The ATTENTION ASSIST function is particularly helpful on long journeys and when driving at night; the system warns the driver if it detects signs of failing attention and increasing weariness. Between 80 and 180 km/h, ATTENTION ASSIST warns the driver visually and audibly as soon as it detects any signs of drowsiness or inattention. The background: sensors analyse driving behaviour to detect any changes compared with the previously determined individual driver profile.
ADAPTIVE BRAKE braking system The ADAPTIVE BRAKE system provides enhanced ride comfort and safety. With the anti-lock braking system ABS it helps drivers to master critical braking manoeuvres. Thanks to the functions for “dry braking” in wet conditions and “priming”, the brakes react even more directly. When starting on an incline unintentional rolling back is prevented and if you press the brake pedal a second time the HOLD function keeps the vehicle securely in its place.
Intelligent Light System with LED daytime running lamps and cornering light function (optional) The Intelligent Light System ensures the best possible visibility in all weather conditions and the most diverse traffic situations. When encountering oncoming traffic, in curves, fog or on free stretches of road the system adjusts to the situation adapting the characteristics of the light individually. Country mode illuminates both the road surface and the edge of the road, motorway mode the entire width of the road. The extended fog lamp function improves visibility, whilst the active light function and the cornering light function follow the driver's steering angle.

Phase 2: In the event of danger

Many accidents can be prevented right up to a few seconds before impact. This very short period of time is at the heart of the PRE-SAFE® system. Mercedes-Benz first introduced the system in 2002 and has continued to develop it ever since. PRE-SAFE® can sense critical situations and prevent accidents as well reduce their after-effects.
The PRE-SAFE® electronics of the new SLK process this information and initiate preventive measures to protect occupants in response to typical dangerous situations. These measures include automatic tensioning of the seat belts, automatic positioning of the passenger seat (in conjunction with the memory function) and automatic closure of side windows.

Phase 3: In an accident

A host of safety systems work together in the new SLK to prevent accidents. Should the worst come to the worst, however, a number of occupant safety measures are activated. They include protection for the vehicle occupants as well as for other road users:

At the core: the extremely rigid passenger cell and crumple zones ensure a high level of occupant safety. The reinforced A-pillar and the rollover bars also give the Roadster outstanding structural strength.
If required: depending on the accident type, the six airbags and belt systems are selectively activated. The sensor system only activates the restraint systems that are actually needed.
All-round protection: depending on the predicted severity of a collision, the adaptive front airbags in the SLK can be deployed in two stages (in a minor collision, in the first deployment stage the airbag is only partially filled). In side-on collisions exceeding a defined threshold, newly-developed head and sidebags in the flanks of the seat backrests are deployed on the impact side. The headbags deploy from the upper edge of the door inner sides, the sidebags are integrated on the outside edges of the seat backrests.
Safety is all in the head: crash-responsive head restraints improve occupant protection and help to reduce the risk of whiplash injury. In the event of a rear-end collision the head restraints are instantly displaced by around 40 mm towards the front and 30 mm upwards, providing support for the seat occupant's head at an earlier stage.
Intelligent protection for other road users: the standard active bonnet function can help reduce the risk of injury to pedestrians or cyclists colliding into the bonnet if the car is travelling at a speed between 25 and 55 km/h. To cushion the blow, the bonnet springs up by approx. 8.5 centimetres at the rear.

Phase 4: After an accident

To reduce consequential damage after an accident and support the work of the rescue services, a number of different actions are initiated, depending on the type and severity of the accident:

Optimum protection: The engine can be turned off automatically and the fuel supply can be cut off.
Safe lighting: hazard and emergency interior lights can activate to lower the risk of accidents and help locate the car.
Aiding escape: the side windows can be partially lowered and the door locking mechanism can be automatically released.
Measure to aid rescue: integral crash joints between the wing and the door can make opening the doors after a frontal collision easier.

Mercedes-Benz has also published multilingual rescue guidelines (accessible worldwide on the internet) as a source of information for rescue services.