What is AEB?

Most manufacturers use this type of system, and it can save your life - but what is AEB?

BuyaCar team
Jun 14, 2021

Car safety is a field that is always progressing, from the advent of seatbelts to the introduction of airbags. Designed to keep drivers, passengers and pedestrians safer in the event of a collision, car makers are now turning to technology to improve safety.

Autonomous Emergency Braking is a computer-based system that is designed to constantly monitor the space ahead of the car with radars and cameras, in order to sense approaching obstacles. If the system detects a hazard, it will warn the driver, and often apply the brakes or supplement the driver's braking.

Let's explore what it means:

Autonomous - a system that acts without the active input of a driver
Emergency - it will only intervene when it deems that you're on course for a collision
Braking - the system will apply the brakes

Once reserved for more expensive models, it is now finding home in smaller and cheaper cars. Pretty soon, you can expect every new car to offer AEB alongside other cutting edge safety technology. Read on for more details on how Autonomous Emergency Braking works.

Why buy a car with AEB?

AEB can act as a safety net in an emergency. You might think that you’ll never need it, but there are often factors outside of your control that can affect your judgement. The car manufacturers cite poor visibility and even glare from sunshine as a major reason for the take-up of AEB systems in their cars.

Of course, AEB systems are not fool-proof, and no car makers are saying that it will stop all accidents. But it has been scientifically proven to assist in avoiding accidents, as well as reducing the severity of them.

How does AEB work?

AEB systems use a selection of devices to essentially ‘read’ the road ahead. Most use a radar system teamed with a front facing camera, usually attached to the nose of a car. Many manufacturers are turning away from shiny metal badges to flatter, plastic alternatives, which act as housing for the sensors required to make this technology work.

From behind the wheel, generally, the first sign of the system working will be an on-screen prompt via the dashboard, alerting you to the fact that it thinks you’re about to hit something. If you don’t use the brakes or turn the steering wheel, the car will apply its brakes automatically.

Braking power and ferocity varies from manufacturer to manufacturer, and some of them will deactivate once you use the brakes.

Obviously, manufacturers, along with safety experts, do not recommend relying on AEB instead of your own right foot. AEB doesn’t kick in until the very last moment, and it’s a strong and harsh system that you wouldn’t want to use in every day traffic.

In general, the more expensive systems work up to a higher speed than cheaper systems. Most accidents occur in city driving at around 12-15mph and most AEB systems work at up to 25mph, but some work at motorway speeds too.

AEB Safety testing

Euro NCAP is a safety assessment program that every new car in Europe has to be put through. It awards cars on a star-based system, the safest cars get five stars, the most unsafe get zero.

Not only do AEB systems make a car safer for the occupants, but it’s proven to make them much safer for pedestrians. Pedestrians and cyclists account for 30% of all fatalities in the EU every year. Because of this, pedestrian and cyclist safety is a growing concern for Euro NCAP.

One of the criterias on which new cars are assessed is a pedestrian test. This is designed to check how well pedestrian-detection systems work. The tests represent common situations that cause pedestrian casualties. In these simulations, generally, when an AEB system is used, accidents that would normally result in a fatal collision can be avoided.

Safest cars in 2019 according to Euro NCAP

AEB benefits

Autonomous Emergency Braking can save lives, particularly when a driver might be momentarily distracted at the wrong time. Generally, the system makes the car safer: better for you, and better for pedestrians. It can also make insurance cheaper. A recent study by Thatcham Research found that cars fitted with AEB systems were £80 a year cheaper to insure than the same car without the system. The savings can be even more for younger and less experienced drivers.

AEB drawbacks

Obviously, the safety benefits far outweigh the drawbacks of such systems. However, if you’re the type of person that doesn’t like electronic systems interfering with your driving, AEB might irk you.

Each manufacturer's system works differently, and some don’t like you getting too close to the car in front during motorway driving. Cheaper systems can get confused between pedestrians and other cars in traffic.

Which cars have AEB?

Volkswagen Golf front view

Here are the cars that have been tested by Euro NCAP that are equipped with Autonomous Emergency Braking systems. Remember, not all are fitted with this technology as standard, and some models needed to be equipped with this optionally (at a cost). On top of this, not all models of the same generation necessarily have this safety kit - sometimes manufacturers introduce these updates halfway through a car's life. To be sure, consult the specific vehicle's spec sheet or contact the manufacturer.


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