What is Brake Assist?

1996 Mercedes-Benz S-Class, along with the Mercedes-Benz SL, was the first production model to have brake assist.

The 1996 Mercedes-Benz S-Class was the first production model (along with the SL-class) to have brake assist

It seems counterintuitive, but when most people “panic brake” they don’t brake as hard as they could. Researchers aren’t sure why that is but the result is that even experienced drivers were in a collision that might have been avoided had the car’s full braking capability had been used.

It might be possible to teach drivers how to slam on the brakes and hold ‘em down, but getting that 90 percent who don’t fully throw out the anchor—much less identifying them—into driver training is highly unlikely. The second best alternative then is to have the car brake for them.

A joint project between Daimler-Benz (maker of Mercedes-Benz automobiles) and TRW/Lucas-Verity, a “component supplier”, developed a system that would identify panic braking by the driver, and then develop something to do about it.

What was learned was that even drivers who don’t keep the pedal pressed to the floor  do react quickly, so the original M-B/TRW system reads how fast the brake pedal is pushed. If the pedal is fast enough, the system maxes out brake boost pressure and the brakes are applied harder. Brake assist can reduce stopping distances by as much as twenty percent.

A refinements of brake assist reads how quickly the gas pedal has been released and “pre-tensions” the brakes—takes the “slack out of the system”—to reduce braking distance by just that little bit more…which may be just enough.

Brake assist was first available on the 1996 Mercedes-Benz S-Class sedans and SL-Class roadsters and is now standard on all Mercedes models and models of other premium makes as well. Applications are increasingly common on lower priced models as well as brake assist becomes an industry standard, much as anti-lock brakes have become.

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