Advanced Driver Assistance Systems (ADAS) Explained

We all want to be as safe as possible on the road. To this end, most modern vehicles are equipped with advanced driver assistance systems (ADAS) that help minimize the chance of an accident. These systems monitor the road conditions around you and can alert you or even intervene if a potentially dangerous situation arises. 

ADAS is a general term that covers many different systems. These are often referred to as driver safety features or active safety features. Many have been legally required for new cars since the early 2010s, and more are required regularly as lawmakers try to reduce the number of traffic accidents. Some manufacturers also equip their models with more features than required by law, either as standard or as optional extras.

It is worth noting that the most important factor in ensuring road safety is careful and attentive driving. ADAS features are a safety system, not a substitute for careful driving. However, it is useful to know what the various ADAS features are and how they work because you are more likely to experience their effect in everyday driving. Here are the features you are most likely to come across.

What is automatic emergency braking?

Automatic or autonomous emergency braking (AEB) can perform an emergency stop if the vehicle's sensors detect an impending collision. It's so effective at reducing the likelihood - or at least the severity - of an accident that safety experts have called it the most important advance in car safety since seat belts.

There are several types of AEB. The simplest ones can detect a stationary car in front of you in slow motion with frequent stops. More advanced systems can operate at much higher speeds, and some can detect cyclists and pedestrians who may be crossing your path. The horn will alert you to danger, but if you don't react, the car will stop on its own. 

The stop is very sudden because the car is applying full brake force, which you are unlikely to ever do yourself. The seatbelt pretensioners will also be activated, pressing you very tightly into the seat, and if your car has a manual transmission, it will probably stall if you don't press the clutch.

What is active cruise control?

Conventional cruise control systems allow you to set a certain speed, which the car then maintains, most often on high speed roads such as motorways. If you need to slow down, you turn off the cruise control with a button or by pressing the brake pedal. Then, when you're ready, you pick up speed again and turn the cruise control back on.

Active—or adaptive—cruise control still operates at the maximum speed you set, but it uses sensors at the front of the vehicle to maintain a safe distance between your vehicle and the vehicle ahead. If he slows down, so will you. You don't have to touch the brakes or gas at all, you just have to steer. When the vehicle in front moves or accelerates, your vehicle will automatically accelerate to the speed you set.

More advanced systems can work in stop-and-go traffic, bringing the car to a complete stop and then picking up speed automatically. 

Find out more about how your car works

Explanation of warning lights on car dashboard

What is DPF?

What is an in-car infotainment system?

What is Lane Keeping Assistance?

There are several types of systems designed to prevent a vehicle from leaving its lane. They are broadly divided into two parts: Lane Departure Warning, which warns you if you are crossing white lines on either side of the lane, and Lane Keeping Assist, which actively guides the car back to the center of the lane.

Cameras at the front of the car pick up white lines and can detect if you cross them without warning. Lane Keeping Assist will alert you, usually with a horn, flashing light, or seat or steering wheel vibration. Some vehicles use a combination of these warnings.

If you specify to rebuild, the system will not work. Most vehicles have an option to disable the system.

What is traffic jam assistance?

Traffic Jam Assist combines advanced Active Cruise Control and Lane Keeping Assist to accelerate, brake and steer in slow traffic, which can make things a lot easier. It works best on motorways, and the most sophisticated systems can even help your car change lanes if necessary. However, the driver must still keep an eye on the road and be prepared to regain control of the vehicle if necessary.

What is Blind Spot Assistance?

Blind Spot Assist (also known as Blind Spot Warning or Blind Spot Monitor) detects if there's another vehicle in your vehicle's blind spot - that's the view from over your right shoulder that your side mirrors can't always show. If the vehicle is there for more than one or two seconds, an amber warning light will come on in your vehicle's exterior rearview mirror, indicating that you should not enter the road of another vehicle. If you indicate when a car is nearby, you will usually hear an audible warning, see a flashing light, or both.

What is Rear Cross Traffic Alert?

Rear Cross Traffic Alert uses sensors and/or cameras to detect if a vehicle, cyclist or pedestrian is about to cross your path when you reverse out of a parking space. A warning will sound, and if you do not respond, brake in the same way as with automatic emergency braking. Some vehicles also have a front cross traffic alert system that works the same way at T-junctions.

What is hill start assist?

If you drive a car with a manual transmission, you know that they can roll back a little when you start uphill when you move your right foot from the brake pedal to the gas pedal. In older cars, you would counteract this by applying the handbrake, but cars with hill-start assist will hold the brakes for a moment after your foot releases the brake to keep the car from rolling backwards.

What are active headlights?

Active or adaptive headlights automatically switch between high and low beam when oncoming traffic is detected. More advanced active headlights can redirect the light or block out some of the high beams so you can see as far ahead as possible without dazzling oncoming drivers.

What is traffic sign recognition?

Traffic Sign Recognition uses a tiny camera system mounted at the front of the car to detect and interpret traffic signs. You will then see a picture of the sign on the driver's digital display so you know what he said, even if you missed it the first time. The system specifically looks for speed and warning signs.

What is Smart Speed ​​Assistance?

Intelligent Speed ​​Assist uses traffic sign recognition and GPS data to determine the speed limit for the section of road you are driving on and issues a continuous warning if you exceed that speed. More advanced versions of the system can limit the vehicle's speed to the current limit. You can override the system - in emergencies or if it misreads the limit - by pushing harder on the accelerator.

What is Driver Attention Detection?

Driver Attention Detection uses sensors inside the car to determine if the driver is paying enough attention to the road. Sensors look at the position of the head and eyes and notice if the driver is looking at the phone, looking in the glove compartment, or even falling asleep. An audible, visual or vibration warning is given to attract the attention of the driver. There may also be an image or text message on the driver's display prompting you to take a break. 

Cars have many other safety features that help protect you and your passengers in the event of an accident. You can read about them here.

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