Autonomous Emergency Braking – Why, When, How?
Euro NCAP, the European car safety programme, announced a few days ago that from 2014 onwards, all cars that hope to get a five-star rating need to be equipped with an Autonomous Emergency Braking (AEB) system.
This is actually the first step in making such a system mandatory equipment on all cars sold across Europe, just like ABS and ESP.
The decision to include AEB technologies in the Euro NCAP assessment programme pretty much makes sense and can only be good news for the entire European Union, although some car manufacturers may need to invest more money to develop such a system.
There are already plenty of companies offering an AEB system, although they’re using a different name. Some are offering them as stand-alone products, others have included them into larger safety packages, but regardless of the way they reach the market, AEB technologies can have a great contribution to a safer traffic.
Volvo, Mercedes, Volkswagen, Mazda, Ford and others already developed such a system, so making it available on many more models across their range was only a matter of time. So let’s see what’s the deal with the AEB system, why do we need it and, more importantly, how it works to avoid accidents.
Sometimes AEB systems can fail to work properly and Volvo knows it perfectly.
If you don’t see a reason for AEB technologies becoming mandatory equipment for five-star ratings, then you probably need to see a bunch of statistics concerning road safety in the last few years.
According to official figures, the number of traffic fatalities in the US dropped by 3 percent between 2009 and 2010, from 33,808 to 32,788. While that’s a good news that less people are killed on the road, it’s only a living proof that all efforts need to be continued all over the world, regardless if we’re talking about authorities, car manufacturers, drivers, pedestrians and everybody else.
Judging only by its name, an autonomous emergency braking system can’t do much good in this regard since most of the deadly accidents take place at high speeds outside the city.
Well, it actually can, especially when these accidents involve pedestrians. Since most systems are developed to work exclusively at city speed, it’s pretty obvious that they could avoid accidents involving pedestrians too.
NHTSA said that in 2009 approximately 25 percent of the accidents that led to the death of pedestrians happened from 6 pm to 9 pm, which is actually a rush hour interval when people go back from work to home. On urban roads, that is.
The short answer would be 2014. This is actually the year when Euro NCAP will include AEB in its assessment program, which means that cars developed to get five stars in the crash tests need to come with this system too.
But as we said a bit earlier, many car manufacturers already offer such a technology. For example, premium brands that include Volvo, Infiniti and Mercedes sell AEB systems as part of much more advanced systems, but Jaguar, Audi, Lexus and Range Rover also allow its buyers to order an optional AEB.
More companies are likely to include the system in its offering very soon, including Mazda on its new CX-5, Volkswagen on the new Up and even Fiat on the brand new Panda.
AEB seems to follow the same path as ABS and ESP. Back in 2007, the European Union decided to make ABS compulsory on new cars, while last year in November it announced that by October 31st, 2013, all cars sold within the EU must come with ESP as standard equipment.
It’s just a matter of time till AEB becomes compulsory too, but this isn’t likely to happen before 2015.
The same Volvo City Safety system, this time working properly.
As we said, there are multiple similar products on the market, but they’re in essence the same pretty simple system.
In just a few words, AEB uses sensors or radars installed on the front of the vehicle, some at the top of the windshield, to monitor the road ahead. Based on a few factors that include speed and distance to the vehicle in front, a control unit detects the risk of an impact.
In most cases, front-mounted radars, cameras, sensors, or whatever technology carmakers adopt, don’t look farther than 6 to 8 meters, so that’s why they work up to 30 or 40 km/h (around 20 mph).
Based on the aforementioned process, the driver is informed about the risk of an accident and is required to push the brakes. In the meantime however, AEB pre-charges the brakes, thus allowing the car to react properly whenever the driver reacts.
In case the driver fails to react, AEB technologies can apply the brakes with full power, bringing the vehicle to a stop in order to either avoid an accident or at least reduce damage.
Of course, if the driver pushes the brakes or changes direction, AEB turns itself off and simply continues monitoring the traffic ahead.
A virtual demonstration of Honda's Collision Mitigation System. It includes an AEB technology too.
As you can see, it’s all a simple system actually, although we all know that many more components are there in order to make such a technology work properly. The good thing is that it does its job and sometimes can react even better than an experienced driver.
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As a graduate student in the Sustainable Transportation Program at the University of Washington I've become increasingly interested in the subject as technological challenges have been overcome, and social, legal, and political considerations become more important. Even though it is early days I've taken the step to begin writing a blog called (tongue in cheek) "Apeless Carriage". One of my blogs posts deals specifically with the adoption of passive safety systems (abs, seat belts)and the similarities that process may have to the adoption of autonomous (active) systems. Your article is a great overview of the present state of affairs, I'll include a link to it in my blog. Thanks! Lars Christian