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MERCEDES-BENZ CONTINUES LEADERSHIP IN VEHICLE SAFETY
Tele Aid, Smart Front Airbags, Side Curtain Airbags Join A Long History of Innovation

MONTVALE, NJ - Mercedes-Benz, the company that invented many of the significant automotive safety features in widespread use today, now equips every model it offers in the USA with the acclaimed Tele Aid emergency calling system, ESP stability control and front and side airbags. As well, Mercedes addresses the crucial issue of side impact protection with its side curtain airbags, which are standard in all 2001 C-Class, E-Class and S-Class sedans, plus CL-Class coupes. These innovative airbags span the entire length of the sides of the passenger compartment from A- to C-pillar, to help protect front and rear passengers in side impacts. In addition, the all-new 2001 C-Class sedans and the S-Class sedans, plus M-Class SUVs and the CL-Class coupes feature smart, dual-stage front airbags, which can deploy at partial or full force, depending on the severity of impact.

Tele Aid: Help Is Just A Button Away

Having debuted last year on the 2000 S-Class sedan, Tele Aid provides both convenience and emergency services at the touch of a button through a special cellular connection. All 2001 Mercedes-Benz models come with Tele Aid, which this year incorporates remote diagnosis, emergency door unlocking and theft alarm notification.

Fundamentally, Tele Aid offers four distinct services. For emergency help, an "SOS" button above the rear-view mirror immediately establishes voice contact with response specialists who can dispatch local police or other emergency services. If a collision deploys any airbag, Tele Aid automatically establishes contact, relaying all pertinent information. The onboard transmitter is crash-secure and has access to redundant antennae. Mercedes-Benz was first to make emergency calling like this standard.

The two non-emergency uses of Tele Aid include a button marked with a wrench, which puts the client in contact with Mercedes-Benz Roadside Assistance, while another button marked "i" connects users with the Mercedes-Benz Client Assistance Center, a facility that can answer questions about the car. An additional benefit of Tele Aid is vehicle theft tracking, which can actually help authorities locate the car once reported stolen. Tele Aid eliminates the need to dial a phone number, use a cellular access code, juggle a handset or locate street names during an emergency. Moreover, the standard Tele Aid system does not require a cellular phone or service - it operates on its own cellular system.

Side Curtain Airbags

Working in conjunction with existing door-mounted side airbags (themselves first introduced to the auto industry on Mercedes E-Class and SL models in 1996), the new side curtain airbag is the only system that can prevent both front and rear occupants from hitting their heads on the side window or roof pillars in a severe side impact. In addition, the air-filled cushion can block glass splinters or other objects, which could cause injury in a side impact or rollover. About six feet long, 14 inches in height and roughly two inches thick, each curtain bag deploys from the ceiling from directly above the side windows in about 25 milliseconds and extends across the front and rear windows. There is a curtain airbag on each side of the car.

Door Airbags Work in Conjunction with Curtain Side Airbags

The curtain side airbag is the latest in a long line of safety innovation from Mercedes-Benz. Starting with the 1998 lineup, Mercedes made door-mounted side airbags standard on every model. The side airbags work as part of the Supplemental Restraint System (SRS) to reduce the possibility of injury in a direct side impact, or an offset-frontal impact. Rear door- and side-mounted airbags are standard in C-, E-, S-, M- and CL-Classes.

BabySmart And Brake Assist Across the Board, Too

In the past few years, the company has introduced other significant safety advances. Standard on all 2001 Mercedes models, the patented BabySmart system deactivates the passenger-side front airbag when a special BabySmart-compatible child seat is placed in the car. In addition, Mercedes-Benz equips every car with Brake Assist, which senses emergency braking situations and automatically applies full braking force.

First with Crash Compatibility for Sport Utilities

The Mercedes-Benz M-Class sport-utility vehicles are the first SUVs to be designed for crash compatibility with passenger cars. Unlike most SUVs, the frame in the M-Class is designed so that it will not override a car?s body structure (and safety systems) in a collision. Such consideration for compatibility could lessen the severity of frontal impacts between different categories of vehicles.

Safety as a Guiding Philosophy

Since the 1930s, when it introduced independent suspension and self-adjusting brakes, Mercedes-Benz has implemented innovative engineering and features that greatly enhance automotive safety. Mercedes-Benz vehicles incorporate extensive active and passive safety features. Active features that help the driver avoid mishaps include ABS anti-lock brakes, traction control, ESP stability control and responsive suspension and steering. Passive features that prevent or limit injury if an accident occurs include full front airbags, side-impact airbags, side curtain airbags, energy-absorbing car body design, strong seat structures, interior padding, seatbelts and seatbelt tensioners.

Four key safety features widely used today trace their roots to Mercedes-Benz safety research:

the energy-absorbing car body - Patented in 1951, the "crumple zone" design combines a rigidly constructed passenger compartment, or cell, with energy absorbing front and rear body structures.

ABS anti-lock brakes - Now available in almost every car line offered in North America, both domestic and imported, an anti-lock braking system was first offered by Mercedes-Benz two decades ago. An acronym trademarked by Mercedes-Benz in 1972 which translated "anti-blocking system", ABS preserves directional stability and steering during emergency braking and has been standard equipment in all U.S. Mercedes models since the 1989 model year.

Supplemental Restraint System (SRS) - Mercedes-Benz coined the term Supplemental Restraint System (SRS) for the group of features that include front airbags, knee bolsters and front three-point seatbelts with Emergency Tensioning Retractors (and starting in 1998, door-mounted side airbags throughout the line). While ETRs remove seat-belt slack just as the airbags begin to deploy, the Mercedes-Benz SRS system now also incorporates belt force limiters which relax the belts slightly as restraining forces build on the chest later in the collision sequence. Mercedes has done pioneering work developing airbags and emphasizing that airbags are most effective when used as part of an overall safety system.

traction control - Mercedes was the first carmaker to introduce a form of traction control, called Automatic Locking Differential (ASD) in 1986. Since then, the company has advanced the technology with today?s full-range ASR traction control. ASR applies the brakes momentarily to one of the rear wheels whenever the wheel speed sensors indicate a wheel is going faster (slipping) than the others during acceleration. The system works at all speeds and can also reduce the throttle electronically if necessary to restore traction. ASR traction control is now standard on all passenger cars, while the M-Class SUVs and E-Class models ordered with optional 4MATIC all-wheel-drive employ a four-wheel electronic traction control system.

Mercedes-Benz Introduces ESP on Cars

Introduced on some 1996 model-year cars and now standard across the board, Mercedes? Electronic Stability Program (ESP) works invisibly to help the driver maintain control in hazardous driving conditions. This breakthrough system uses sensors to constantly monitor individual wheel speed, steering angle (the driver?s desired direction) and lateral acceleration (actual cornering force), as well as an advanced yaw sensor derived from aircraft technology. From these inputs, ESP can determine if a car is going in the direction the driver intends. Should the car become unstable and begin experience an incipient slide or spin, ESP temporarily applies brake pressure at one wheel - something no driver can do - to restore the driver?s intended path. ESP can even reduce throttle to help restore stability. In effect, ESP detects when a car is going "off course" and, like an invisible hand, puts it back "on course." The system is on at all times and works on any road surface.

Other Active Safety Features

The G-force sensitive brake proportioning system represents an advance in controlled braking. For maximum stopping power in a straight line, the system permits 60 percent total braking power directed to the front wheels and 40 percent to the rear. If it detects hard braking while cornering, the system directs 70 percent braking power to the front and 30 percent to the rear, minimizing the possibility of rear lock and loss of control.

The G-force brake proportioning system joins other Mercedes brake innovations, including servo-assisted disc brakes in 1961 (for improved braking) and ABS (to help maintain control during emergency situations) in 1978. Mercedes also offers a rear axle level control system, which automatically keeps the car level, regardless of cargo weight. In addition to preserving suspension geometry, this feature keeps the headlights properly aimed and also improves ride quality, even when the car is carrying a full load.

Other Passive Safety Features

Mercedes-Benz engineers have made dramatic advances in passive safety systems, including the first standard "occupant friendly" interior in 1959, incorporating energy-absorbing features like a padded steering wheel hub, sun visors, door trim, arm rests, a yielding instrument panel and recessed door handles.

Just as important, Mercedes seatbacks have been shown to withstand rear-end collisions far in excess of U.S. federal standards, so the seats don?t have a tendency to collapse backward.

The Safety Cell

A rigid passenger cell and Mercedes-patented "crumple zones" help absorb impact before it reaches passengers. The front and rear structures of the body have been designed to collapse at a pre-determined rate upon impact. Forked front frame members also aid in dissipating energy, especially in offset collisions (the 1998 SLK introduces a refinement of this design concept called ellipsoid bulkhead).

Airbag Design Pioneer

Mercedes was the first carmaker to make a driver?s side airbag standard equipment as part of its restraint system; all Mercedes models today also have a standard front passenger airbag and front door-mounted side airbags, which help protect occupants during a side impact. Dedicated sensors determine the severity of the side impact, and, within five milliseconds, trigger the respective side airbag. The bags are fully inflated 12 milliseconds later. This compares to the front airbags, which, in a car moving at 30 mph, have about 40 milliseconds to inflate.

Emergency tensioning retractors for the seat belts, which remove normal slack in the belts to increase their effectiveness in a collision, have been standard equipment on Mercedes cars since 1984, and belt force limiters made their debut on the 1996 E-Class and are featured on all 2001 Mercedes models.

Other key features include a fuel tank that is mounted ahead of the trunk, well away from the rear of the car, as well as a hood, front fenders and fold-flat side mirrors which are even specially designed to minimize injuries to pedestrians or cyclists who may be struck.

Summary of The Most Significant Mercedes-Benz Safety Innovations

1938 - self-adjusting brakes
1939 - prototype safety vehicle
1951 - safety car body with rigid passenger cell and front and rear crumple zones
1959 - first laboratory impact and rollover tests
1959 - "occupant-friendly" interior
1961 - servo-assisted disc brakes
1967 - first energy-absorbing steering wheel and column
1969 - investigation and analysis of traffic accidents (in Germany) involving Mercedes cars
1971 - fuel tank over rear axle and separated from passengers by steel panel
1971 - ribbed "anti-soil" tail lamps
1973 - front three-point seatbelts
1974 - rear three-point seatbelts
1978 - electronic anti-lock brake system (ABS)
1980 - first offset crash car design
1981 - front shoulder belt height adjustment
1983 - Supplemental Restraint System (SRS) in North America
1984 - emergency tensioning retractors to take out normal slack from seatbelts on impact
1986 - first headlamp wiper/washers for U.S. models
1988 - full front airbag system offered in North America
1990 - first automatic deploying rollover bar (SL coupe/roadsters)
1990 - first seatbelts integrated into seats (SL coupe/roadsters)
1992 - G-force brake proportioning system (S-Class)
1994 - full-front airbags standard on all Mercedes models in North America
1995 - Electronic Stability Program (ESP)
1996 - Door-mounted side airbags for driver and front passenger
1997 - BabySmart child seat detection system (1998 SLK roadster)
1998 - Brake Assist system, SUV crash compatibility
1999 - Side curtain airbags (E-Class sedans)
2000 - Tele Aid emergency calling system (2000 S-Class)
2000 - Smart front airbag, deploys in partial or full force, dependent on impact severity (S-Class)

© 2005 Marcus Blair Fitzhugh

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