Forward Collision Warning

How does it work?

It is a collision warning system, in the event that the vehicle driven is too close to colliding with a parked or moving vehicle ahead. This is done   using a sensor that is mounted on the front of the vehicle (e.g., RADAR, LIDAR and/or camera).

These warning systems are useful in alerting the driver to dangerous situations ahead, helping them respond more quickly when the need arises. The type of warning used by the systems varies between vehicles. Some use a flashing light while others use an alarm or vibration sound.

Forward collision warning systems should not be confused with forward collision mitigation systems. Warning systems simply warn the driver when a collision is likely to occur, but do not automatically apply the brakes. It is also important to note that different vehicles have the ability to detect different types of crashes. Some vehicles will only sound the alarm if you are about to collide with another moving vehicle, for example.

Graphic: Forward collision warning icon


  • Forward collisions are among the most common types of crashes. Forward collision warning systems are therefore of great benefit, as research has shown that they can substantially reduce the risk and severity of these types of collisions.
  • Being a technology that alerts the driver about potentially dangerous situations, a conceptual benefit is that this technology has the ability to increase people’s confidence in continuing to drive safely, even when they are hampered by factors such as aging.


  • This technology is designed to warn drivers about possible hazards so that the driver can make the right decisions. Therefore, forward collision mitigation systems are not considered within this technology spectrum.
  • It is still a feature mainly present in luxury vehicles, but in combination with other active technologies, it has the potential to become standard equipment and increase its market penetration.
  • It is a feature that depends on the attention, dexterity, and good judgment of the driver for its complete effectiveness. At all times, active user surveillance is required.
  • The type of system used for forward car detection can influence its use, as camera-based systems are less effective at night than radar-based systems, and can be “blinded” by direct sunlight (e.g., early dawn and late sunset). Likewise, the effectiveness of systems based on cameras and radars can be compromised by the accumulation of snow or ice in front of the sensors.

Common names

  • Forward Collision Warning (FCW)
  • Collision Avoidance Assist
  • Collision warning with brake support
  • Adaptive cruise control with forward collision warning of automatic tail assist steering
  • Forward collision warning
  • Forward collision warning with brake mount
  • Forward collision warning with mitigation
  • OEM 4 Active Safe
  • Proximity warning function

Latest Publications on PubMed

Search results for: forward collision warning

  • Are front crash prevention systems less effective at preventing rear-end crashes where trucks and motorcycles are struck?
    by Jessica B Cicchino on March 11, 2024 at 10:00 am

    OBJECTIVE: Automatic emergency braking (AEB) and forward collision warning (FCW) are effective at preventing rear-end crashes, but they may perform better in some rear-end crash scenarios than others. The goal of this study was to estimate the effects of front crash prevention systems equipped to passenger vehicles in crashes where another passenger vehicle, a medium/heavy truck, or a motorcycle is struck and compare effectiveness by struck vehicle type.

  • Optimization of Forward Collision Warning Algorithm Considering Truck Driver Response Behavior Characteristics
    by Yanli Bao on February 10, 2024 at 11:00 am

    Forward collision warning (FCW) systems have been widely used in trucks to alert drivers of potential road situations so they can reduce the risk of crashes. Research on FCW use shows, however, that there are differences in drivers' responses to FCW alerts under different scenarios. Existing FCW algorithms do not take differences in driver response behavior into account, with the consequence that the algorithms' minimum safe distance assessments that trigger the warnings are not always...

  • Forward Collision Warning Strategy Based on Millimeter-Wave Radar and Visual Fusion
    by Chenxu Sun on December 9, 2023 at 11:00 am

    Forward collision warning (FCW) is a critical technology to improve road safety and reduce traffic accidents. However, the existing multi-sensor fusion methods for FCW suffer from a high false alarm rate and missed alarm rate in complex weather and road environments. For these issues, this paper proposes a decision-level fusion collision warning strategy. The vision algorithm and radar tracking algorithm are improved in order to reduce the false alarm rate and omission rate of forward collision...

  • Comparison of Experienced and Novice Drivers' Visual and Driving Behaviors during Warned or Unwarned Near-Forward Collisions
    by Jordan Navarro on October 14, 2023 at 10:00 am

    Forward collision warning systems (FCWSs) monitor the road ahead and warn drivers when the time to collision reaches a certain threshold. Using a driving simulator, this study compared the effects of FCWSs between novice drivers (unlicensed drivers) and experienced drivers (holding a driving license for at least four years) on near-collision events, as well as visual and driving behaviors. The experimental drives lasted about six hours spread over six consecutive weeks. Visual behaviors (e.g.,...

  • Adaptive forward collision warning system for hazmat truck drivers: Considering differential driving behavior and risk levels
    by Yichang Shao on July 20, 2023 at 10:00 am

    The risky driving behavior of hazmat truck drivers is a crucial factor in many severe traffic accidents. In-vehicle Advanced Driving Assistance Systems (ADAS), integrating vehicle active safety and driver assistance technology, has been installed into hazmat trucks aiming to reduce driving risks during emergencies. This paper presents an enhanced dynamic Forward Collision Warning (FCW) model tailored for hazmat truck drivers with different driving characteristics and risk levels. Our objective...

  • How can front crash prevention systems address more police-reported crashes in the United States?
    by David G Kidd on July 5, 2023 at 10:00 am

    Government and consumer-information organizations can motivate automakers to address additional crash types through front crash prevention (FCP) testing programs. This study examined the current state of crashes potentially relevant to current and future FCP systems to provide a roadmap for the next crash types that vehicle testing programs in the United States should evaluate. Crash records from 2016 to 2020 were extracted from the Crash Report Sampling System (CRSS) and the Fatality Analysis...

  • Characteristics of automatic emergency braking responses in passenger vehicles evaluated in the IIHS front crash prevention program
    by David G Kidd on June 10, 2023 at 10:00 am

    Researchers can estimate the potential safety benefits of front crash prevention (FCP) systems by simulating system performance in rear-end crash scenarios reported to police or captured during naturalistic driving. Data to support assumptions about FCP systems in production vehicles, particularly automatic emergency braking (AEB), are limited. This study used detailed information from the Insurance Institute for Highway Safety's (IIHS's) FCP evaluation to characterize interventions in vehicles...