How Brake Assist Works

How Brake Assist Works

If you’ve ever driven a car on a featureless highway, you’re likely familiar with the sensation of zoned-out driving. You may have even wished the automobile could drive itself.

Now consider the following: You have selected a lovely day to visit faraway friends. You and your vehicle are consuming highway miles. Life is fantastic when the satellite radio is playing your favorite songs and the sunroof is open, allowing you to tan in the car. In reality, you are slowly lulled into a driving trance until you reach the top of a hill, at which point you see an array of brake lights immediately in front of you. You pump the brake pedal, fully anticipating that you would rear-end the automobile in front of you. Your automobile somehow comes to a stop barely feet from the nearest vehicle. You breathe a sigh of relief as you recall that the auto dealer mentioned brake assist on the day you purchased your stallion.

Compared to current electronic sensors, human reaction times are rather slow. The objective of brake assist and associated technologies is to enable us to stop our automobiles more quickly and more quickly. These crucial seconds, which are typically fractions of a second, can be the difference between a collision and a narrow escape.

So, is brake assist a truly valuable safety feature or only a cunning marketing ploy aimed to sell more automobiles and increase sticker prices? Many studies demonstrate that brake assist has the potential to avoid tens of thousands of fatal auto accidents annually.

In this post, we’ll examine what enables brake help to stop cars far more swiftly and effectively than a driver operating a vehicle without assistance. With power brakes and anti-lock brakes available, why would a driver require more assistance stopping a vehicle? Understand why by navigating to the following page.

The Reason for Brake Assist

Why would a driver want brake help when there are currently so many different braking capabilities available on a normal automobile? What if the electronic devices that activate it become overly sensitive, causing jerky stops whenever the driver presses the brakes? Car enthusiast publications have long criticized these electronic “nannies” for removing much of the skill and excitement from driving.

Simply said, brake assist is for safety. Simply put, research indicates that the majority of individuals are overly timid with their brakes in an emergency. According to Mercedes-Benz, 99 percent of drivers in emergency stopping situations either failed to apply full brake application or applied brake pressure too late. In the late 1990s, when Mercedes introduced the technology to the market, the manufacturer claimed that brake assist reduced stopping distance by 45 percent. Even skilled drivers benefited from 10 percent shorter stopping distances [source: Mercedes-Benz]. In terms of safety, shorter stopping distances translate to fewer accidents.

Engineers have taken measures to prevent the powerful braking system from engaging unintentionally. Automotive engineers refer to brake assist as a driver-adaptive system. In other words, the electronics that govern brake assist monitor and measure the driver’s typical driving behaviors, including brake use. The system is able to distinguish between slowing down at a traffic light and stopping abruptly when a youngster runs into the roadway.

Automakers have been known to reject new safety improvements on occasion due to their extra expense. Mercedes-Benz and parts supplier TRW/LucasVarity, however, invented brake assist and began offering it on their automobiles [source: Mercedes-Benz]. The technology first appeared on the consumer market in 1996, when Mercedes-Benz S-Class and SL-Class models were introduced. The company made the feature standard on all vehicles in 1998. Since then, several manufacturers, including Acura, Audi, BMW, Infiniti, Land Rover, Rolls Royce, and Volvo, have offered their own versions of brake assist.

Providing Power for Panicked Stops

How Brake Assist Works

Let’s perform another assisted-braking stop. This time, we’ll tackle it step by step.

You are traveling along a deserted country road on a moonless night, with the forest on either side seemingly closing in. Your high beams emit just enough light to allow you to comfortably drive the posted speed limit. A family of deer suddenly appears on the road a few hundred feet ahead.

As your foot automatically clamps down on the brake pedal, a sensor quickly recognizes, by the speed and pressure of your foot on the pedal, that this is an emergency. Within a fraction of a second, the brake assist system sends a signal to the brakes to apply maximum clamping force to the brake calipers. The brake pedal vibrates as the anti-lock braking system (ABS) and the brake assist engage. The truck remains under control as it decelerates and stops far short of the crossing deer. No animals are harmed – – and your insurance premium escapes equally unscathed.

There are several types of brake assist. Volvo offers the City Safety system, which automatically brakes in urban stop-and-go traffic [source: Volvo]. Distronic Plus is an additional feature developed by Mercedes-Benz. Toyota has developed a system that combines navigation data with a vehicle’s brake assist system, enabling the brake assist to activate during panic stops at traffic signals [source: Toyota].

Active Brake Assist is a more recent technological advancement that applies hydraulic pressure to the brakes milliseconds before a collision. This expedites the delivery of additional stopping force to the brakes. German component manufacturer Bosch names its version Predictive Brake Assist. It’s designed to connect with the vehicle’s Adaptive Cruise Control radar sensor to spot scenarios that could evolve into an accident. Beyond a certain threshold, the system prepares the vehicle for a sudden stop by applying light brake pressure that the driver won’t even notice. In excess of a second proximity threshold, the device initiates the complete brake assist mechanism.

Why is all this necessary? Are drivers on the road truly that slow to react? Bosch sees this innovation as vital since, “even in severe situations, only approximately a third of drivers respond effectively and press the brakes firmly enough.” As a result, according to the firm, “the hydraulic brake-assist system is not activated” [source: Robert Bosch GmBH].

Does brake assist improve driving safety? Proceed to the next page to learn more.

Collision Free Cars

How Brake Assist Works

Brake assist has proven to be so effective at preventing accidents that the European Commission (EC) intends to mandate its installation on all new vehicles sold in Europe. If all cars in Europe were equipped with this technology, the European Commission estimates that 1,100 pedestrian lives may be saved annually [source: eSafety Support]. Like with stability control and anti-lock brakes, brake assist appears to be one of those technologies that were originally exclusive to luxury vehicles but will soon become standard on all automobiles.

How much safer would U.S. roadways be if obligatory brake assist technology was implemented? According to the Insurance Institute for Highway Safety (IIHS), more than 400,000 accidents occur annually in which the driver reacted by attempting to halt or avoid a collision. Over 3,000 people per year are killed in these accidents [source: United States Institute of Insurance Highway Safety]. There is no accurate method to determine how many of these accidents could have been averted if the driver had stopped sooner, but it appears that brake assist can reduce accidents when used in conjunction with other innovative safety technologies.

In addition, there is some evidence to corroborate this: The “Future Vehicles” research by the Insurance Institute for Highway Safety examined five relatively new automobile safety systems, including brake assist, forward collision warning, lane departure warning, blind spot detection, and adaptive headlights. According to the Institute’s study [source:], if all vehicles were fitted with these five safety features, they could avert 3,4 million accidents and 20,777 deaths annually.

There is no need to be an automotive futurist to recognize that, with a little fine-tuning or perhaps more processing capacity, these technologies could someday lead to self-driving automobiles. That might substantially reduce collisions. In exchange for increased safety, are individuals willing to relinquish control of their vehicle to a computer? In many cultures, automobiles and trucks are still connected with personal mobility and a sense of autonomy. But, it is almost clear that innovations like braking assist, made possible by quick-thinking electronics, will continue to make driving significantly safer.

Please read the links on the following page for additional details on braking assist and other car safety features.

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