The automotive industry has embraced the rapid technology-driven innovation curve to make driving easier and our roads safer and more efficient. One of these technologies is Advanced Driver-Assistance Systems or ADAS.

ADAS are a group of systems that assist drivers in various aspects of driving, enhance their on-road safety and improve the overall driving experience. In this article, we will explore ADAS in more depth covering common ADAS functionality, how it works and its contribution to risk management and reducing road accidents.

What are Advanced Driver-Assistance Systems (ADAS), and how do they work?

Advanced Driver-Assistance Systems (ADAS) incorporate a suite of safety technologies integrated into vehicles that augment the driver's skills and awareness on the road. ADAS monitor the vehicle's surroundings in real time with the help of sensors, radars, cameras and other components.

These components continuously collect data about the vehicle's environment including proximity to other cars, road markings, traffic signs and pedestrians. On-board computers process this data and, if a potential threat is detected, ADAS can alert drivers by applying automatic emergency braking systems or dashboard alerts such as Lane Departure Warning (LDW) systems.

However, it is important to note that ADAS is not a fully autonomous driving system. A driver must always remain vigilant and engaged and view ADAS as a driving assistant and a safeguarding layer to reduce accidents.

Common Features of ADAS

There are several features of ADAS that are becoming more common to vehicles manufactured within the past decade, including associated pros and cons.

1. Adaptive Cruise Control (ACC)

Adaptive Cruise Control uses sensors like radar or LIDAR to take traditional cruise control to the next level. The sensors monitor the distance between your vehicle and the one ahead. They can automatically adjust the vehicle's speed to maintain a safe driving distance even in varying traffic conditions, something that conventional cruise control cannot do.

Drivers can set a maximum speed and following distance in the system. Once the vehicle in front slows down, the system automatically reduces your vehicle's speed to maintain the set distance and return to the preset speed once the road ahead is clear.


  • Enhanced driving comfort: ACC reduces the need for constant braking and accelerating, resulting in a smoother driving experience and improved driving comfort, especially during long journeys.
  • Reduced driver fatigue: With ACC managing speed automatically in traffic, drivers can focus more on the road, be more aware and reduce mental fatigue while driving, especially during longer routes.
  • Reduced accidents: Automatic braking, speeding up and maintaining the preset following distance help reduce rear-end collisions, crash severity and tailgating and lowers stress in congested traffic.
  • Better fuel efficiency: Maintaining a consistent speed and the following distance optimises fuel consumption as well.


  • Sudden changes in traffic patterns: ACC may not respond optimally to abrupt changes in traffic flow, requiring the driver to take control in some situations.
  • Inattentive drivers: Just because the car can stop automatically doesn't mean drivers can relax while driving. Drivers need to stay alert and be ready to take control if required.
  • Close following distance: It's essential to understand that vehicles need time before stopping completely. Drivers can set a following distance that is too close for the car to stop in case of an emergency.

2. Lane Departure Warning (LDW) and Lane Keeping Assist (LKA)

While both features function separately, they work together to ensure your vehicle is in the correct lane. The LDW system tracks lane markings with the help of cameras and alerts the driver if the vehicle unintentionally drifts out of its lane. LKA, on the other hand, helps keep the car in its specific lane by actively intervening and gently steering the vehicle to prevent unintended lane departure.


  • Accident prevention: LDW and LKA help reduce lane departure accidents, especially during driver distraction or drowsiness. LDW uses sound, lights and vibrations to alert the driver of the vehicle changing its current lane.
  • Safer lane changes: LKA provides additional assistance during lane changes, reducing the risk of collisions with adjacent vehicles.


  • Poorly marked roads: On poorly marked or faded roads, the system may need help to detect lane markings accurately, leading to false alerts or reduced effectiveness.
  • Weather conditions: Adverse weather conditions like heavy rain or snow can hinder the system's performance, forcing the driver to take over completely.

3. Forward Collision Warning (FCW) and Emergency Automatic Braking (EAB)

Sometimes drivers can respond late to sudden brakes by the vehicle in front, leading to rear-end collisions. Distracted drivers are also a significant cause of such accidents.

The FCW system monitors the distance between your vehicle and the one in front with the help of sensors. The system will alert the driver immediately if it detects an imminent collision. EAB takes this safety a step further by applying the brakes autonomously to prevent or reduce the severity of a crash.


  • Collision avoidance: FCW and EAB significantly reduce the risk of rear-end collisions, the most common type of accident. It can also be lifesaving during unpredictable situations, like a child suddenly coming in front of the vehicle.
  • Mitigating collision impact: In situations where the collision cannot be avoided, EAB can significantly minimise the impact and any injuries.


  • False alarms: FCW and EAB can frighten drivers by getting activated without an apparent cause. This can be due to bad weather, road conditions, sharp curves or a vehicle cutting in your lane but accelerating away rather than stopping.
  • Limited detection range: EAB's effectiveness is limited to its sensor range and may not detect objects beyond a certain distance.

4. Blind Spot Monitoring (BSM)

Good driver visibility is essential to safe road traffic. Drivers often have difficulties registering vehicles or obstacles in their blind spot and can have accidents. With BSM, these accidents can be reduced considerably. BSM employs sensors that detect cars in your blind spots, usually located on the sides and rear of your car, and provide a visual or audible warning when a vehicle is detected in the blind spot.


  • Enhanced awareness: BSM improves situational awareness significantly when changing lanes or merging onto highways, reducing the likelihood of side-swipe accidents.
  • Safety during lane changes: BSM acts as an extra pair of eyes, making lane changes safer and more confident.


  • BSM limitations: If the vehicle is travelling at a significantly different speed or if it is partially obstructed, then the system will have difficulty detecting anything in the blind spot.
  • Over-reliance: The availability of such systems can make drivers complacent, leading them to neglect proper shoulder checks and overlook other potential hazards.

5. Rear Cross-Traffic Alert (RCTA)

While there are multiple mirrors for drivers to look at what's behind them, they can still end up colliding with vehicles or pedestrians. The RCTA system monitors approaching vehicles or pedestrians from the sides when reversing and alerts the driver if a collision is about to happen. This is especially useful in crowded parking lots or driveways.


  • Avoiding backing collisions: RCTA prevents collisions with vehicles or pedestrians that may be obscured from the driver's view.
  • Enhanced parking safety: Drivers can back out of parking spots with increased confidence and safety.


  • Limited detection range: RCTA's effectiveness is constrained to the area immediately behind the vehicle, and fast-moving objects may be challenging to detect.

How ADAS reduce accidents

ADAS play a critical role in driver awareness, reducing accidents and enhancing road safety. By providing real-time information about traffic, pedestrians and obstacles in front of the vehicle, drivers are able to respond faster and thereby reduce avoidable incidents. The different features of ADAS help to reduce rear-end collisions, blind spot accidents, lane departure incidents and other common causes of accidents.

Given that the majority of road accidents are the result of human errors, ADAS can compensate for momentary lapses in concentration such as distractions, fatigue and timing errors. Enhanced driver awareness through ADAS will be integral to reducing critical injuries, collision damage and avoidable disruption to traffic flows.

As ADAS technology continues to evolve, we can expect to see the emergence of ‘connected cars’, with vehicle-to-vehicle sharing of information providing a detailed picture of the vehicle’s perimeter and earlier warnings plus corrective actions to avoid collisions. All of this will contribute to safer cars and safer roads, with ADAS becoming central to risk management practice for vehicle fleets.

Considerations for managing fleet risk

A UK-based research project found that accident frequency in the UK can be reduced by nearly 24% if most common ADAS features are fully deployed1. In the first half of 2021, the LKA feature of ADAS was integrated into 56% of the new cars sold in Europe. In the US, 63% of the vehicles were integrated with the same features2.

This shows the increased adoption of ADAS in new cars and its benefits in preventing traffic accidents. For businesses managing fleets of vehicles, ADAS can be a prudent step to minimise fleet risk and improve overall safety. It can assist drivers in complying with traffic laws and avoiding accidents due to human errors. Reduced accidents enhance the reputation of the fleet and reduce money spent on repairs or insurance.

However, fleet managers must ensure that drivers are fully aware of the capabilities and limitations of ADAS and don't take it for granted. Proper training and education should be given to drivers to use these features and their driving skills to reduce accidents considerably. They should also ensure that ADAS sensors are regularly maintained and calibrated to ensure optimal performance.

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