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    Driver Assistance Technologies

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      Overview
                      Driver assistance technologies hold the potential to reduce traffic crashes and save thousands of lives each year. In 2022, 42,514 people died in motor vehicle crashes — many of these crashes were tied to human error. Learn more about driver assistance technologies, how they can help you, and what you should know about these technologies when buying your next vehicle.

          
                    
          
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                                Safety Facts

                                                  42,514
      LIVES LOST ON U.S. ROADS IN 2022
      Source

        Driver Assistance Technologies
                                                                                                              The Topic
                                                                                                  Technologies Explained
                                                                                NHTSA In Action
                                                                                Resources

      Technology Saves Lives
                                      Tech Overview
                                      Tech In Your Car
                                                        Collision Warning
                                      Collision Intervention
                                      Driving Control Assistance
                                      Other Systems

        Driver Assistance Technologies
      The Topic
                      
                                              Technology Saves Lives
                                                          Tech Overview
                                                          Tech In Your Car
                                                                              Technologies Explained
                      
                                              Collision Warning
                                                          Collision Intervention
                                                          Driving Control Assistance
                                                          Other Systems
                                                                              NHTSA In Action
                                                                              Resources

                    The Topic
                  

                  Technology Saves Lives
          
          
    
  
       
  

      Jason Fenske of 'Engineering Explained' Explains
          Blind Spot & Forward Collision Warnings
              Plus, Automatic Emergency Braking & Pedestrian Automatic Emergency Braking
          Watch the video
    

 
  Driver assistance technologies in your car not only help to keep you and your passengers safe, but also other drivers and pedestrians. When shopping for a new or used vehicle, you may notice that different manufacturers use different names for the technologies. NHTSA is helping consumers break through the confusion with explanations about how these technologies work. It’s important to understand that some driver assistance technologies are designed to warn you if you’re at risk of an impending crash, while others are designed to take action to avoid a crash. Be sure to review your vehicle’s owner’s manual for more information on your vehicle’s technology and safety features. Understanding how the technology works and how it can better protect you, your passengers and others is key.The Topic
                  

                  Tech Overview
          
          
    
  
       
  
      Collision Warning
                          Collision Intervention
                          Driving Control Assistance
                          Other SystemsForward Collision Warning

                Detects a potential collision with a vehicle ahead and provides a warning to the driver.

*This is a NHTSA recommended safety technology.*
                          
                            
                            Lane Departure Warning

                Monitors the vehicle’s position within the driving lane and alerts the driver as the vehicle approaches or crosses lane markers.

*This is a NHTSA recommended safety technology.*
                          
                            
                            Rear Cross Traffic Warning

                Warns the driver of a potential collision, while in reverse, that may be outside the view of the backup camera.
                          
                            
                            Blind Spot Warning

                Warns of a vehicle in the driver’s blind spot.
        Blue Car
Automatic Emergency Braking

                Applies brakes automatically when a forward collision is imminent. There are two types of automatic emergency braking systems that meet NHTSA’s performance specifications: dynamic brake support and crash imminent braking.

*These are NHTSA recommended safety technologies.*
                          
                            
                            Pedestrian Automatic Emergency Braking

                Detects a pedestrian in front of the vehicle and automatically applies brakes if a collision is imminent.
                          
                            
                            Rear Automatic Braking

                Detects a potential collision while in reverse and automatically applies brakes if a crash is imminent.
                          
                            
                            Blind Spot Intervention

                Applies brakes or provides steering if the driver begins to change to a lane where a vehicle is detected in the blind spot.
        Blue Car
Adaptive Cruise Control

                Automatically adjusts the vehicle’s speed to keep a pre-set distance from the vehicle in front of it.
                          
                            
                            Lane Centering Assistance

                Provides continual steering to keep the vehicle centered in its lane.
                          
                            
                            Lane Keeping Assistance

                Automatically and gently steers to prevent the vehicle from departing the lane.
        Blue Car
Automatic High Beams

                Automatically switches the vehicle’s headlights between low and high beams when an oncoming vehicle approaches based on lighting conditions and traffic. This is also known as semi-automatic beam switching.
                          
                            
                            Backup Camera

                Provides the driver with a clear view directly behind the vehicle when in reverse. This is also known as a rearview video system.
                          
                            
                            Automatic Crash Notification

                An automatic crash notification system notifies emergency responders that a crash has occurred and provides its location.
        Blue CarThe Topic
                  

                  Tech In Your Car
                Technologies Explained

 
  
Collision Warning
				Forward Collision Warning
                      Lane Departure Warning
                      Rear Cross Traffic Warning
                      Blind Spot Warning

 
  
NHTSA Recommends Forward Collision Warning
		Search by Vehicle to See If FCW Is Available
   
  Forward Collision Warning
Forward collision warning

 
    
      A forward collision warning system monitors the vehicle’s speed, the speed of the vehicle in front of it and the distance between the vehicles. If the vehicle gets too close to the vehicle ahead, the system will warn the driver of an impending crash. It’s important to note that forward collision warning systems only provide a warning to the driver and do not take action to avoid a crash. *Watch how it works.*
  
 
    
  More on how FCW works
              Forward collision warning systems use sensors to detect slower-moving or stationary vehicles. When the distance between vehicles becomes so short that a crash is imminent, a signal alerts the driver so that the driver can apply the brakes or take evasive action, such as steering, to prevent a potential crash. Vehicles with this technology provide drivers with an audible alert, a visual display, or other warning signals. This helps prevent frontal crashes into the rear of slower moving or stopped vehicles.

 
  
NHTSA Recommends Lane Departure Warning
		Search by Vehicle to See If LDW Is Available
   
  Lane Departure Warning
Lane departure warning

 
    
      A lane departure warning system monitors lane markings and alerts the driver when it detects that the vehicle is drifting out of its lane. It’s important to note that a lane departure warning system only provides a warning to the driver and does not take action to avoid a crash.
  
 
    
  More on how LDW works
              A lane departure warning system uses a camera to detect when the vehicle is veering out of its lane. An audio, visual, or other alert warns the driver of the unintentional lane shift so the driver can steer the vehicle back into its lane. This provides a valuable safety benefit and can help keep drivers and passengers safe from crashes such as when a vehicle strikes a car in an adjacent lane, including sideswiping a vehicle traveling in the same direction or hitting a vehicle traveling in the opposite direction. Also, lane departure warning could prevent incidence of road departure and subsequent crashes off roadway.

 
  Rear Cross Traffic Warning

 
    
      Rear cross traffic warning alerts the driver of potential collisions, while in reverse, that may be outside the view of the backup camera.
  
 
  Blind Spot Warning

 
    
      Blind spot warning systems alert drivers with an audio or visual warning if there are vehicles in adjacent lanes that the driver may not see when making a lane change. *Watch how it works.*Collision Intervention
				Automatic Emergency Braking
                      Pedestrian AEB
                      Rear Automatic Braking
                      Blind Spot Intervention

 
  
NHTSA recommends dynamic brake support and crash imminent braking systems
		Search by Vehicle to See If These Systems Are Available
   
  Automatic Emergency Braking
automatic emergency braking

 
    
      Automatic emergency braking systems apply the vehicle’s brakes automatically in time to avoid or mitigate an impending forward crash with another vehicle. NHTSA believes AEB systems represent the next wave of potentially significant advances in vehicle safety. Dynamic brake support and crash imminent braking are AEB systems that potentially save lives and reduce moderate and less severe rear-end crashes that are common on our roadways. *Watch how it works.*
  
 
    
  More on how DBS and CIB systems work
              If the system detects a crash and the driver brakes, but not hard enough to avoid the crash, DBS automatically supplements the driver’s braking to avoid a crash. If the system detects a crash but the driver does not brake to at all, CIB automatically applies the vehicle’s brakes to slow or stop the car, avoiding the crash or reducing its severity.
Extensive research on this technology and on relevant performance measures showed that a number of AEB systems currently available in the marketplace are capable of avoiding or reducing the severity of rear-end crashes in certain situations.

 
  Pedestrian Automatic Emergency Braking

 
    
      A pedestrian automatic emergency braking system uses information from forward sensors to detect a pedestrian in the vehicle’s path. The system will provide automatic braking if the driver has not acted to avoid a crash. *Watch how it works.*
  
 
  Rear Automatic Braking

 
  

      Watch the video
    

 
    
      Rear automatic braking uses sensors, like parking sensors and the backup camera, to detect objects behind the vehicle. If the system detects a potential collision while in reverse, it automatically applies the brakes if a crash is imminent.
  
 
  Blind Spot Intervention

 
  

      Watch the video
    

 
    
      Blind spot intervention helps prevent a collision with a vehicle in the driver’s blind spot. If the driver ignores the blind spot warning, and starts to change to a lane where there’s a vehicle, the system activates and automatically applies light braking pressure, or provides steering input to guide the vehicle back into the original lane. The system monitors for vehicles in the driver’s blind spot using rear-facing cameras or proximity sensors.Driving Control Assistance
				Adaptive Cruise Control
                      Lane Centering Assistance
                      Lane Keeping Assistance

 
  Adaptive Cruise Control

 
    
      Adaptive cruise control automatically adjusts the vehicle’s speed to keep a pre-set distance between it and the vehicle in front of it.
  
 
  Lane Centering Assistance

 
    
      Lane centering assistance utilizes a camera-based vision system designed to monitor the vehicle’s lane position and automatically and continuously apply steering inputs needed to keep the vehicle centered within its lane.
  
 
  Lane Keeping Assistance

 
  

      Watch the video
    

 
    
      Lane keeping assistance helps prevent the vehicle from unintentionally drifting out of its lane. The system uses information provided by lane departure warning sensors to determine whether the vehicle is about to unintentionally move out of its lane of travel. If so, the system activates and corrects the steering, brakes or accelerates one or more of the wheels, or does a combination of both, resulting in the vehicle returning to its intended lane of travel.Other Systems
				Automatic High Beams
                      Backup Camera
                      Automatic Crash Notification

 
  Automatic High Beams

 
  

      Watch the video
    

 
    
      Automatic high beams automatically switch the vehicle’s headlights between the lower beam and the higher beam, based on lighting conditions and traffic, when an oncoming vehicle approaches. This technology, also known as semi-automatic beam switching headlamps, uses photometric sensors or onboard cameras to detect when to switch between high and low beams.
  
 
  Backup Camera

 
    
      A backup camera, also known as a rearview video system, helps prevent backover crashes and protect our most vulnerable people — children and senior citizens. By providing an image of the area behind the vehicle, a backup camera helps the driver see behind the vehicle while in reverse. It’s important to remember that backup cameras are not a replacement for mirrors or turning around to look. As of May 2018, NHTSA requires this lifesaving technology on all new vehicles. *Watch how it works.*
  
 
  Automatic Crash Notification

 
    
      An automatic crash notification system is designed to notify emergency responders that a crash has occurred and provide its location. In most cases, when the system detects that an air bag has deployed or that there’s been a dramatic and sudden deceleration, the system automatically connects to an operator, who will then be able to communicate with the driver. The operator is also able to collect basic information from the vehicle, without driver input, to provide to emergency responders so they can easily locate the scene of the crash. Automatic crash notification systems can reduce death and disability by decreasing the time it takes for emergency medical services to arrive at a crash scene and transport victims to a hospital.
                NHTSA In Action
                  

                  NHTSA promotes the safe use and manufacture of vehicle equipment
          
          
    
  
       
  NHTSA promotes the safe use and manufacture of vehicle equipment.
Through safety standards and consumer information, NHTSA demonstrates its commitment to reducing crashes and saving lives in the United States. NHTSA works to inform consumers about the types of driver assistance technologies that are available and which technologies we recommend.
We now know that driver assistance technologies are the right path toward safer roads. We will work diligently to bring you updated information whenever there are breakthroughs with new driver assistance technologies.
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