Mercedes-Benz Offers DISTRONIC PLUS Radar-Based Adaptive Cruise Control

Made possible by the DISTRONIC PLUS adaptive cruise control, another revolutionary Mercedes-Benz safety feature – PRE-SAFE® brake – can apply full braking automatically in emergencies, to reduce accident severity. Available on the S-Class sedan, CL and CLS coupe, SL roadster, M-Class sport utility and E-Class line for 2013, the system sounds three warning tones when PRE-SAFE Brake senses an impending collision. About 1.6 seconds before impact is likely, partial braking is automatically initiated, and the PRE-SAFE occupant protection system are activated. If the driver still fails to react, full-power braking is initiated about 0.6 seconds before the collision, reducing the impact and effectively acting as an "electronic crumple zone."

DISTRONIC PLUS Makes Stop-and-Go Traffic a Breeze

The DISTRONIC PLUS system, which operates at nearly all speeds up to 124 mph, can be especially helpful in stop-and-go traffic. The adaptive cruise control feature helps maintain a pre-determined distance behind the car in front, while the automatic braking feature can slow the car to a stop if necessary.

DISTRONIC PLUS uses three beams of short-range radar with a frequency of 24 gigahertz sweep the first 33 yards in a fan-shaped 80-degree pattern, working with a narrower nine-degree beam of longer-range 77-gigahertz radar. The two radar frequencies complement each other to cover a full range of more than 160 yards – more than 1½ football fields. During approval of the new 24-gigahertz radar frequency for automotive use, government agencies cited its potential to improve traffic safety, reduce injuries and ultimately save lives.

Radar-Based Blind Spot Assist and Park Assist

The DISTRONIC PLUS system now includes Blind Spot Assist, which monitors both blind spots behind the vehicle. Whenever a turn signal is activated with a vehicle in the blind spot, the driver gets visual and audible warnings.

The latest radar-based DISTRONIC PLUS also incorporates Park Assist, which utilizes six radar sensors mounted behind the front and rear. At low speeds, the system scans available parking spaces and displays a "P" in the dash if the car will fit in the space. When the car's in reverse, Park Assist displays a top-view pictogram of the car and parking space, providing helpful steering guidance.

The Proven PRE-SAFE SYSTEM

PRE-SAFE Brake builds on the original PRE-SAFE system that Mercedes-Benz launched in 2002. PRE-SAFE® automatically tightens the front seat belts during those valuable seconds just before a possible impact, and the front passenger seat (and optional power rear seats) move to positions that can provide better protection. If the system senses an impending rollover, the sun roof closes as well. Side windows also close to provide better support for the window curtain air bags, and seat cushions inflate to provide greater lateral support for occupants.

DISTRONIC Adaptive Cruise Control

The basic DISTRONIC adaptive cruise control (without the automatic emergency braking feature) uses one radar sensor at the front of the car to help maintain a pre-set distance from the car ahead. Taking its name from the words "distance" and "electronic," DISTRONIC is an available option on a number of 2013 vehicles.

The DISTRONIC system operates much like conventional cruise control – tip the stalk on the steering column, and the car maintains its set cruising speed. With DISTRONIC, the driver also selects a following distance, and when a DISTRONIC-equipped vehicle recognizes a slower moving vehicle in its path, it automatically slows down to maintain the following distance. Pull into a clear left lane, and the car resumes its original speed setting. If a slower car pulls in front, the DISTRONIC car again slows down to preserve the pre-set following distance. The following distance can be adjusted via a thumbwheel on the stalk.

Not only does DISTRONIC reduce throttle opening and downshift the transmission to control vehicle speed, but it can also apply partial braking automatically if needed, to help maintain the desired following distance.

A red triangle in the instrument panel lights up, and an audible beep sounds when the system recognizes that it cannot maintain the established following distance. A pictogram helps the driver monitor the car ahead. The driver can make the following distance a little closer by scrolling a stalk-mounted thumbwheel forward, and by scrolling rearward, the following distance is increased.

Radar Sensor Makes It Work

Mounted behind the grille, a radar module sends out a cone-shaped beam that covers about one traffic lane. This 77-gigahertz radar beam can project up to several hundred feet down the road, and the sensor receives any signals that are reflected back from objects ahead. The radar sensor sends the information about objects ahead to a microprocessor via a discrete circuit, and in turn, the microprocessor decides how to vary the acceleration and whether to apply the brakes.

The system is designed not to recognize stationary objects or oncoming traffic. The major benefit of DISTRONIC cruise control is that it makes driving more relaxed and less stressful.
PRE-SAFE® Teams Up With Brake Assist and DISTRONIC PLUS

In the early 1990s, Mercedes-Benz engineers conducting simulator tests discovered that many drivers don't push the brake pedal hard enough and soon enough in emergency braking, a discovery that led to the development of Brake Assist, standard equipment on all Mercedes-Benz vehicles since late 1990s. Brake Assist has proven itself a time and again, and simulator tests have shown that vehicles equipped with Brake Assist are involved in 26 percent fewer accidents.