Automated Vehicle Terminology

Active Safety System: A vehicle-based system that uses sensor input (such as cameras and radar combined with computers and controls) to detect a potential traffic safety issue, then warn the driver and/or make a brief automatic intervention to help mitigate or prevent a collision. This is distinct from Passive Safety Systems, such as seat belts, which mitigate damage and injury after a collision.

Adaptive Cruise Control (ACC): Adaptive cruise control is a cruise control system that maintains a driver-set speed and uses sensors and automation to adjust the vehicle speed to ensure the vehicle doesn’t get too close to vehicles ahead. This is distinct from traditional cruise control, which maintains a set speed until the driver changes it.

Advanced Driver Assistance Systems (ADAS): A term describing and encompassing all systems that use advanced Active Safety technologies to support human drivers by performing a part of the driving task if engaged. Examples include Adaptive Cruise Control and Automatic Emergency Braking.

Antilock Braking System (ABS): A form of vehicle automation that is required on all new vehicles sold in the United States, antilock brakes help prevent loss of traction that can occur when wheels “lock up,” or stop rotating and skid along the road. ABS systems detect when wheels are locking up and automatically pulse the brakes on and off, sometimes many times a second, to prevent lock-up and help increase traction.

Artificial Intelligence (AI): A broad term for computer systems that can gather, process and use information to perform better. AI systems are important for advanced vehicle technologies because they can help automated vehicles operate more safely and effectively.

Automatic Emergency Braking (AEB): An active safety system that uses sensors (such as cameras and radar) combined with computers and controls to sense when a vehicle is approaching a slower moving or stopped vehicle in the same driving lane and apply the brakes automatically – even if the driver doesn’t take action. These systems can help avoid or reduce the impact of crashes when drivers fail to take action to avoid a crash.

Automated Vehicle (AV): A very broad term that can be used to describe any vehicle with some level of automation (Level 1 through 5 on the SAE International scale).

Blind Spot Monitoring (BSM): An active safety system that uses sensors (such as radar) to sense when a vehicle or other object is in or quickly approaching a driver’s “blind spot” – an area where the object is hard to see in rear-view mirrors. These systems usually use warning lights or beeps to warn the driver.

Connected Vehicle: A vehicle equipped with wireless communications technology that enables communication with other vehicles, connected infrastructure, the internet or other networks.

Driverless Vehicle: A broad term, but generally applied to fully automated vehicles (Level 4 and 5 on the SAE International scale) that can operate without a driver.

Electronic Stability Control (ESC): A form of vehicle automation that is required on all new vehicles sold in the United States, Electronic Stability Control helps drivers maintain control of their vehicle during extreme maneuvers. ESC systems sense a loss of vehicle stability and automatically apply braking to one or more wheels to help the vehicle remain stable.

Fully Automated Vehicle: A broad term, but generally applied to vehicles (Level 4 and 5 on the SAE International scale) that can operate without a driver.

Lane Centering: A system that uses cameras or other inputs and automated controls to help a vehicle stay in the center of a travel lane.

Lane-Keeping Assist (LKA): An active safety system that uses cameras or other inputs to and automated controls to keep a vehicle in the lane of travel. This technology is different from Lane Centering as the vehicle is directed back into lane but is not aligned in the center.

Levels of Automation: Technical terminology developed by SAE International and widely adopted by industry and safety advocates to describe the various levels of technology in vehicles, from no automation at all to full self-driving. These are important for engineers, but they can also help drivers understand what their role is in operating a vehicle, so they can safely operate the vehicle. SAE has a handy chart for consumers as well as a highly technical paper explaining the levels, but briefly they are:

  • Level 0: No automation; the driver must fully control all driving tasks
  • Level 1: Driver assistance — the driver is in full control of the vehicle, but design includes some automated driver-assist systems (such as adaptive cruise control).
  • Level 2: Partial automation — vehicle includes systems that can simultaneously control both speed and direction of the vehicle in specific conditions, but with the driver monitoring the driving environment and system’s performance at all times (such as automated parking systems). Level 2 is the highest level of automation available in vehicles which consumers can buy today (for example, GM Super Cruise).
  • Level 3: Conditional automation – vehicle includes systems that can perform all driving tasks under a limited set of conditions, with a driver ready to take over when alerted by the system if required.
  • Level 4: High driving automation – the vehicle is capable of performing all driving tasks within specific conditions (such as only in daytime, or within a specific neighborhood), with no expectation that a driver will be asked to intervene when the vehicle is operating in those conditions.
  • Level 5: Full automation – vehicle is capable of handling all driving tasks in any conditions.

LIDAR: Acronym for Light Detection and Ranging. A type of sensor that uses laser light to sense the environment; many automated vehicles use LIDAR along with radar (which uses radio waves to detect objects) and cameras to detect other vehicles, pedestrians and obstacles on the road. (The prominent, spinning domes or cylinders you may have seen on test vehicle? That’s an example of LIDAR equipment.)

Passengerless Vehicle: A fully automated vehicle designed to travel without any human occupants, generally designed specifically for goods delivery, that can operate without a driver and has no space for passengers.

Pedestrian Detection: A feature that uses sensors such as cameras and/or radar to detect pedestrians or cyclists near a vehicle included in some active safety systems, ADAS, and/or automated vehicles which may warn the driver or take some action to mitigate or avoid a collision with pedestrians and cyclists.

Platooning: Using on-board sensors and communication technology to allow lines of vehicles (“platoons”) to move together along the roadway. When vehicles are connected by radio or other technologies, the following vehicles can use braking and accelerating information from preceding vehicles to mirror the same actions to avoid the accordion effect from delayed braking and accelerating. Experts believe platooning can reduce traffic congestion and fuel consumption.

Radar: Acronym for Radio Detection and Ranging. Systems that transmit radio waves to sense certain objects around them. Active safety systems, ADAS, and automated vehicles use radar to detect other vehicles, pedestrians or other objects

Self-Driving Vehicle: A broad term, but generally applied to fully automated vehicles (Level 4 and 5 on the SAE International scale) that can operate without a driver.

Vehicle-To-Vehicle (V2V) Communications: Vehicles sharing data such as speed, location, and direction with other vehicles within a certain vicinity via communications medium dedicated to high-speed transmission of critical safety information. V2V systems can help prevent crashes (by alerting another vehicle that the two vehicles are on a collision course) and reduce traffic congestion (by helping traffic move more smoothly and efficiently, and helping vehicles avoid traffic jams on the road ahead).

Vehicle-to-Everything (V2X): A catch-all term for vehicles sharing data with other vehicles (V2V); specially equipped infrastructure (V2I); vulnerable road users such as pedestrians, cyclists or scooters; or other communications device. For example, a car could communicate with traffic lights, stopping or slowing as the light signals it’s about to change to red, or triggering a red light to turn green when no opposing traffic is around.