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Mercedes-Benz Stability Control Reduces Accidents

Posted by www.eMercedesBenz.com on June 14, 2006 at 10:00 AM CST

According to a recent study conducted by the Insurance Institute for  
Highway Safety, Electronic Stability Control (ESP), a technology  
pioneered by Mercedes, reduces the likelihood of all fatal accidents  
by 43% and fatal single-vehicle crashes by 56%.  In addition, the  
Insurance Institute for Highway Safety found that ESP provided a  
substantial benefit to SUV's, reducing rollovers by 80% and reducing  
single-vehicle crashes by 49%.

For those of you unfamiliar with what exactly ESP does, the system's  
main function is to monitor impending loss of control at the front or  
rear end by calculating whether or not the driver's input matches  
what the car is doing.  If any loss of control is detected, the  
system works in a split second by braking individual wheels and/or  
reducing excess engine power, something that even the most skilled  
driver cannot do. In effect, ESP can be compared to having four  
individual brake pedals, one for each wheel, with a powerful computer  
to determine which pedal should be applied when and for how long.

In real world situations, one of the most notable examples of when  
ESP would function is on a slippery road, where the system would help  
the driver prevent oversteer (i.e., rear-end fishtailing) and  
understeer (i.e., front-end plowing).  Many times, however, ESP  
functions invisibly - correcting circumstances that could lead to a  
loss of control without the driver ever realizing there was a problem.

And that, ladies and gentlemen, is a brief overview of what ESP does.

If you'd like to learn more about ESP and gain additional insight  
into the system's inner workings, keep scrolling for the full press  
release.

Enjoy.


OFFICIAL PRESS RELEASE


MERCEDES-BENZ ESP STABILITY CONTROL REDUCES ACCIDENTS


SUVs With Stability Control Have 80 Percent Fewer Rollovers

MONTVALE, NJ – Mercedes-Benz – the well-known automotive company that  
pioneered ABS anti-lock brakes, traction and ESP stability control –  
has further confirmation from the Insurance Institute for Highway  
Safety (IIHS) that the stability control system originally developed  
by Mercedes-Benz dramatically reduces accidents.

Now being used by other manufacturers, stability control systems  
reduce the likelihood of all fatal accidents by 43 percent and fatal  
single-vehicle crashes by 56 percent, according to the most recent  
IIHS accident study! And, when the IIHS recently updated the results  
of their 2004 accident study, they found that stability control  
provides even more life-saving benefits for sport utility vehicles.
Although the safety system provides significant benefits to both cars  
and SUVs, sport utility vehicles with stability control are reported  
to have 80 percent fewer rollovers than vehicles without the system.  
The study also concluded that the risk of all types of single-vehicle  
crashes in an SUV was reduced by 49 percent.

Mercedes-Benz Makes Cars Safer

After bringing the industry’s first ABS anti-lock brakes and traction  
control systems to consumers in the 1980s, Mercedes-Benz invented ESP  
stability control and introduced it in 1995. The new safety system  
made its debut on the 1996 S-Class line and became standard equipment  
on most Mercedes-Benz models by the 2000 model year and is standard  
on all Mercedes-Benz models today.

How Does Stability Control Work?

ESP can sense impending loss of control at the front or rear end. The  
system works in a split second by braking individual wheels and/or  
reducing excess engine power, something that even the most skilled  
driver cannot do. ESP can be compared to having four individual brake  
pedals, one for each wheel, with a powerful computer to determine  
which pedal should be applied when and for how long.

The Mercedes-Benz ESP system helps drivers maintain stability,  
especially on slippery roads, by helping to prevent oversteer (rear- 
end “fishtailing”) or understeer (front-end “plowing”). Even the  
“ESP” abbreviation helps underscore the system’s benefits – it works  
invisibly, seemingly intuitively, to help keep the car going where  
the driver points it, under driving circumstances that might  
otherwise lead to loss of control and a possible accident without the  
system.

Using electronic sensors and lightening-fast computer logic, the  
system constantly monitors a vehicle’s actual path against its  
intended path. If there’s any difference between what the driver is  
“asking” (primarily through the steering wheel) and what the vehicle  
is doing, the system works in a split-second by braking individual  
wheels and/or reducing excess engine power, even before the driver  
may sense any changes.

ESP uses the angle of the steering wheel and the speed of the four  
tires to calculate the path being steered, and it gets electronic  
signals about lateral “g” and vehicle “yaw rate” to measure what the  
car is actually doing. (Yaw can be demonstrated by rotating a small  
model car on a toothpick stuck down through its roof; engineers  
describe the vehicle as rotating around its vertical center axis.)
ESP measures any tendency toward understeer (when a car plows over  
its front wheels) or oversteer (when the rear wheels try to swing  
around, causing the car to “fishtail”). Whenever it senses understeer  
in a turn, ESP increases brake pressure to the inside rear wheel.  
With an oversteer tendency, it increases brake pressure to the  
outside front wheel. For example, if the rear wheels begin sliding to  
the left so the vehicle is yawing clockwise, ESP applies the left  
front brake to counter the yaw and stabilize the vehicle.

Unlike traction control alone, ESP is effective during acceleration,  
braking and coasting. The system enhances driver control and helps  
maintain directional stability in turns as well as when driving  
straight-ahead.
As a joint project of Mercedes-Benz and Bosch, the development and  
testing of the ESP system had been underway for several years before  
its introduction in model year 1996.

For more Mercedes-Benz news and information, visit  
www.eMercedesBenz.com.