What Is an Automatic Braking System?

Child standing in front of oncoming car at night

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Automatic braking technologies combine sensors and brake controls to help prevent high-speed collisions. Some automatic braking systems can prevent collisions altogether, but most of them are designed to simply reduce the speed of a vehicle before it hits something. Since high-speed crashes are more likely to be fatal than low-speed collisions, automatic braking systems can save lives and reduce the amount of property damage that occurs during an accident. Some of these systems provide ​​braking assistance to the driver, and others are actually capable of activating the brakes with no driver input.

How Do Automatic Braking Systems Work?

Each car manufacturer has its own automatic braking system technology, but they all rely on some type of sensor input. Some of these systems use lasers, others use radar, and some even use video data. This sensor input is then used to determine if there are any objects present in the path of the vehicle. If an object is detected, the system can then determine if the speed of the vehicle is greater than the speed of the object in front of it. A significant speed differential may indicate that a collision is likely to occur, in which case the system is capable of automatically activating the brakes.

In addition to the direct measurement of sensor data, some automatic braking systems can also make use of GPS data. If a vehicle has an accurate GPS system and access to a database of stop signs and other information, it can activate its auto brakes if the driver accidentally fails to stop in time.

Do I Really Need Automatic Brakes?

All of this occurs without any driver input, so you don’t have to drive a vehicle with automatic brakes any differently than you would operate any other car or truck. If you remain perfectly vigilant at all times, you probably won’t ever notice that your vehicle even has an automatic braking system.

However, automatic brakes can save your life if you ever suffer from a momentary lapse in concentration. Automatic braking systems are primarily designed as a safeguard against distracted driving, and the technology can also save lives if a driver happens to fall asleep behind the wheel. Many drivers will never need to make use of this type of system, but it’s still a nice safety net to have.

What Systems Make Use of Automatic Brakes?

The primary use of automatic brakes is in precrash and collision avoidance systems. These systems are typically capable of warning the driver of an impending collision, tightening seat belts, and taking other actions that can help prevent an accident or reduce the damage that occurs during a collision.

In addition to pre-crash and collision avoidance systems, many adaptive cruise control systems also make use of automatic brakes. These systems are capable of measuring the speed of a leading vehicle and matching it. They can also reduce speed by cutting the throttle, downshifting, and finally activating the brakes.

How to Find a Vehicle With Automatic Braking

Most automakers offer at least one model that offers either adaptive cruise control or a collision-avoidance system. Some of the first pre-crash systems were introduced between 2002 and 2003 by companies like Honda and Mercedes-Benz, so vehicles manufactured during the intervening decade may or may not be equipped with automatic braking.

Adaptive cruise control has been around longer, but these systems have only recently been able to make use of automatic braking. One of the first automakers to roll out an adaptive cruise control system that can brake to a complete stop is BMW, which introduced the feature in 2007.

Since automatic braking is so effective at reducing fatal collisions, the Insurance Institute for Highway Safety maintains a maintains a list of vehicles that come equipped with specific advanced collision avoidance features like automatic braking, which you can use to identify a safer vehicle that comes with the exact safety features you want.

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