What are advanced driver assistance systems (ADAS)?

Advanced driver assistance systems (ADAS) definition

Advanced driver assistance systems (ADAS) rely on sensors to provide the car’s location for navigation, measure speed and detect other vehicles or objects on the road.

ADAS first came to the market in the early 2000s with laser cruise control and lane-keeping assist. During this decade, most features were in high-end brands like Infiniti, Audi and Cadillac. Now, the National Highway Transportation Safety Administration (NHTSA) plans to require one ADAS feature, automatic emergency braking, on all new vehicles. Most passenger cars already have the feature.

Other ADAS features include collision warning, blind-spot monitoring, adaptive cruise control, adaptive headlights, advanced traction control, GPS navigation and automatic parking. Combined with fleet telematics, these systems can help promote a more efficient fleet for companies as well as give drivers the support to make vehicle operation and accident avoidance easier.

Here is a closer look at the features and benefits of advanced driver assistance systems.

How do ADAS work?

ADAS systems use various sensors to collect data on the car and its surroundings. These include cameras, radar, light detection and ranging (lidar), GPS and sonar.

These devices transmit data in real time to the vehicle’s onboard computer. It collects the information and analyzes it. For instance, it might see information from a radar sensor showing that the car in front of your vehicle is slowing down and causing a rapid decrease in the following distance.

The final component of the ADAS design is the electronic control unit (ECU). Each ECU controls one or more of the functions of a car, including braking, steering, acceleration or lights. ECUs apply the brakes, correct the steering, turn off the high beams or slow the car down when triggered by sensors.

Other features, such as dash cams, do not connect to an ECU, but fleets can use the information to monitor driver performance. Combined with the ADAS systems, you can boost overall safety within your fleet.

Why are ADAS important?

The NHTSA outlines the functions of the most common ADAS systems and their benefits. Each system is designed to address specific road situations and assist the driver as they deal with them.

Forward collision warning and automatic braking detect potential obstructions from cars or objects. It alerts the driver and uses the ECU to help slow the car if the driver doesn’t respond in time. It may also aid attentive drivers in low-visibility situations.
Pedestrian detection with automatic braking can alert the driver if they fail to spot a pedestrian crossing the street in front of them.
Lane departure warning and lane-keeping assist warn drivers and may help correct steering if the car drifts outside its lane. The goal is to limit sideswipe accidents or side impact collisions from lane changes.
Rear automatic braking functions like a forward collision warning system, but only works when the car is in reverse.

The NHTSA also mentions rearview cameras and automatic high beams. These systems may not control the car, but they can increase driver visibility in challenging conditions.

These sensors can interface with ECUs to send alerts to drivers. For instance, a blind-spot monitoring system will light up an icon in the side mirror if a vehicle is in the blind spot. Many systems also provide audio warnings, allowing you to correct your steering, apply the brakes or take other measures early. The ECU will take over if the driver fails to respond to these initial warnings.

Types of ADAS

ADAS systems usually fall into two categories: active and passive. Passive systems provide information and alerts or operate features that assist with safe driving. These alerts include lights, sounds or vibrations. However, passive systems do not control the vehicle, so it is still up to the driver to take accident avoidance measures.

Active systems use the same sensor data as passive ones, but they involve the ECUs. In these systems, the car can perform maneuvers, such as steering or braking, to autonomously help the driver respond to an accident or a dangerous situation.

Passive features

Passive features can provide information to make driving easier as well as offer alerts for accident avoidance.

Adaptive light control uses sensors to control the car’s high beams so that they illuminate the road but automatically turn off when another vehicle is detected.
Navigation systems provide directions and traffic information. In addition to maps, these features often include voice directions allowing you to keep your eyes on the road.
Blind-spot monitoring provides alerts, such as illuminated icons in the side mirrors, steering wheel vibrations and audio beeps, to let drivers know when another vehicle is in their blind spot.
Lane departure warning provides an alert when the car leaves its lane without activating the turn signal.
Parking sensors provide audio and visual alerts, and some combine with a rear-facing video feed and grid or steering directions to help you ease into a parking spot.

Some systems, such as anti-lock braking (ABS), may fall into the passive category because the driver still needs to manually apply the brakes before the ABS feature starts working.

Active features

Active features often offer the same warnings as passive ADAS, but they can take the next step of fully controlling the vehicle.

Adaptive cruise control uses radar, camera or lidar sensors to help keep a car in cruise-control mode at a safe distance from other vehicles by applying the brakes and gas according to sensor input.
Automatic parking uses parking sensors and cameras to steer the car into a parking space based on sensor data about the curb and other vehicles.
Lane-keeping assist aids in steering correction when it senses the vehicle leaving the lane without employing its turn signal.
Automatic braking and front collision avoidance apply the brakes if sensors detect an imminent collision. Usually, the system provides an audible, visual or haptic alert to give the driver time to react before automatically stopping the car.
Traffic jam assist is a type of adaptive cruise control, but it works at low speeds and in stop-and-go traffic.

Active ADAS systems serve as the basis for the development of fully autonomous vehicles. However, since the current ADAS technology may reduce but does not eliminate accidents, fully autonomous driving is still in the early stages of development.

The future of ADAS in fleet management

ADAS features can bolster safety, which in turn can reduce downtime and repair costs due to accidents.

The NHTSA lists the different levels of automation in driving, with Level 0 offering passive ADAS and Levels 1 and 2 providing active assistance. Levels 3 to 5 describe increasingly automated driving, however, these technologies are still in the early stages of development and not ready for use on the road.

While ADAS continues to develop, fleets can get benefits from data collected by onboard sensors to inform a fleet tracking software system. In addition to safety and driver performance, this software can help with predictive maintenance, vehicle location and other information needed for an efficient and safe operation.