Automated emergency braking system explained

The World Forum for Harmonization of Vehicle Regulations define AEBS (also automated emergency braking in some jurisdictions). UN ECE regulation 131 requires a system which can automatically detect a potential forward collision and activate the vehicle braking system to decelerate a vehicle with the purpose of avoiding or mitigating a collision.[1] UN ECE regulation 152 says deceleration has to be at least 5 metres per second squared.[2]

Once an impending collision is detected, these systems provide a warning to the driver. When the collision becomes imminent, they can take action autonomously without any driver input (by braking or steering or both). Collision avoidance by braking is appropriate at low vehicle speeds (e.g. below 50km/h), while collision avoidance by steering may be more appropriate at higher vehicle speeds if lanes are clear.[3] Cars with collision avoidance may also be equipped with adaptive cruise control, using the same forward-looking sensors.

AEB differs from forward collision warning: FCW alerts the driver with a warning but does not by itself brake the vehicle.[4]

According to Euro NCAP, AEB has three characteristics:[5]

Time-to-collision could be a way to choose which avoidance method (braking or steering) is most appropriate.[6]

A collision avoidance system by steering is a new concept. It is considered by some research projects.[6] Collision avoidance system by steering has some limitations: over-dependence on lane markings, sensor limitations, and interaction between driver and system.[7]

History

Early approaches and forward collision avoidance system

Early warning systems were attempted as early as the late 1950s. An example is Cadillac, which developed a prototype vehicle named the Cadillac Cyclone which used the new radar technology to detect objects in front of the car with the radar sensors mounted inside "nose cones". It was deemed too costly to manufacture.

The first modern forward collision avoidance system was patented in 1990 by William L. Kelley.[8]

The second modern forward collision avoidance system was demonstrated in 1995 by a team of scientists and engineers at Hughes Research Laboratories (HRL) in Malibu, California. The project was funded by Delco Electronics and was led by HRL physicist Ross D. Olney. The technology was marketed as Forewarn. The system was radar-based a technology that was readily available at Hughes Electronics, but not commercially elsewhere. A small custom fabricated radar antenna was developed specifically for this automotive application at 77  GHz.

The first production laser adaptive cruise control on a Toyota vehicle was introduced on the Celsior model (Japan only) in August 1997.

Commercial and regulatory development

In 2008, AEB was introduced in the British market.[9]

Between 2010 and 2014, Euro NCAP rewarded various constructors whose system had AEB features.

Euro NCAP rewards! Maker! Year! System
BMW2014 BMW Pedestrian Warning with City Brake Activation
FIAT2013 FIAT City Brake Control
Mitsubishi2013 Mitsubishi Forward Collision Mitigation
Skoda2013 Skoda Front Assistant
Audi2012 Audi Pre Sense Front
Audi2012 Audi Pre Sense Front Plus
VW2012 Volkswagen Front Assist
Ford2011 Ford Active City Stop
Ford2011 Ford Forward Alert
Mercedes-Benz2011 Mercedes-Benz Collision Prevention Assist
VW2011 Volkswagen City Emergency Brake
Honda2010 Honda Collision Mitigation Braking System™ (CMBS™)
Mercedes-Benz2010 Mercedes-Benz PRE-SAFE® Brake
Volvo2010 Volvo City Safety

In the early-2000s, the U.S. National Highway Traffic Safety Administration (NHTSA) studied whether to make frontal collision warning systems and lane departure warning systems mandatory.[10] In 2011, the European Commission investigated the stimulation of "collision mitigation by braking" systems.[11] Mandatory fitting (extra cost option) of Advanced Emergency Braking Systems in commercial vehicles was scheduled to be implemented on 1 November 2013 for new vehicle types and on 1 November 2015 for all new vehicles in the European Union.[12] According to the "impact assessment",[13] this could prevent around 5,000 fatalities and 50,000 serious injuries per year across the EU.

In March 2016, the National Highway Traffic Safety Administration (NHTSA) and the Insurance Institute for Highway Safety announced the manufacturers of 99% of U.S. automobiles had agreed to include automatic emergency braking systems as standard on virtually all new cars sold in the U.S. by 2022.[14] In Europe, there was a related agreement about an AEBS or AEB in 2012.[15] United Nations Economic Commission for Europe (UNECE) has announced that this kind of system will become mandatory for new heavy vehicles starting in 2015.[16] AEBS is regulated by UNECE regulation 131.[17] NHTSA projected that the ensuing accelerated rollout of automatic emergency braking would prevent an estimated 28,000 collisions and 12,000 injuries.[14]

In 2016, 40% of US car model have AEB as an option.[18]

, in the United Kingdom, an estimated 1,586,103 vehicles had AEB. This makes AEB available in 4.3% of the British vehicle fleet.[9]

As of 2021, Consumer Reports shows a rise in automakers making city-speed AEB standard. In 2021, six automakers included AEB on all models, up from two in 2020, indicating increased customer demand for this safety feature.[19]

Australia:

In April 2020 AEB is:

United States:

Since 2015, the NHTSA has recommended AEB for vehicles., it is not mandatory in the US vehicles. However, in 2016, the NHTSA convinced automobile manufacturers to include AEB in 99% of new cars car sold in the US by 1 September 2022.[21]

On 9 June 2021, in Phoenix, USA, a heavy truck going too fast for traffic conditions crashed with seven other vehicles on a motorway, killing four people and hurting nine.[21] Two days later, US National Transportation Safety Board, prepare a nine-person team to investigate this crash, and to assess whether automatic emergency braking in the truck would have helped to mitigate or prevent the crash.[21]

Percent of US vehicles with AEB produced 1 September 2017 to 31 August 2018
(2018 model year)[22]
Percent of vehicles produced Sept. 1 to Aug. 31 with AEB
(2019 model year)
Percent of vehicles produced Sept. 1 to Aug. 31 with AEB (2020 model year)Percent of 2021 models with standard AEB(2021 model year)
As reported by manufacturer for light-duty vehicles or less gross vehicle weightAs reported by manufacturer for light-duty vehicles weighing 3,850 kg (8,500 lb) or lessAs reported by manufacturer for light-duty vehicles weighing 3,850 kg (8,500 lb) or lessAs compiled by Consumer Reports
Tesla100 100100100
Mercedes-Benz96 999794
Volvo93 100100100
Toyota/Lexus90 9297100
Audi87 999983
Nissan/Infiniti78 868282
Volkswagen69 929889
Honda/Acura61 869486
Mazda61 8096100
Subaru57 849957
BMW49 849994
Maserati/Alfa Romeo27 484833
General Motors24 294750
Hyundai/Genesis18 789693
Kia13 597550
Fiat Chrysler10 101420
Porsche8 385550
Ford/Lincoln6 659183
Mitsubishi6 539100
Jaguar Land Rover0 00100

In 2019, 66% of autobrake systems evaluate by the IIHS in 2019 models earn the highest rating of superior for front crash prevention.[23]

Japan:

In 2017, AEB is one of the most popular forms of ADAS in Japan,in Japan more than 40% of newly manufactured vehicles equipped with some type of ADAS had AEB.[24]

In 2018, 84.6% of cars had a kind of AEB in Japan, but the certification goal was not met by each of them.[25]

As a mandatory feature

From the fiscal year 2021, in Japan, all new cars should have automatic braking systems to prevent accidents, including with a car or pedestrian but not with cyclists, at speeds defined by three international regulations.[25]

In the European Union, advanced emergency-braking system is required by law on new vehicle models from May 2022, and all new vehicles sold by May 2024.[26]

In India, autonomous emergency braking system (AEB) could become mandatory on new cars by 2022.[27]

In the United States, automakers voluntary committed to releasing automatic emergency braking as a standard feature on all new cars and trucks starting in 2022, to provide AEB three years earlier than through a regulatory process.[28] AEB is set to be mandatory in cars and light trucks by September 2029.[29]

In Australia where AEB is not yet mandatory, the federal government has suggested in a Regulation Impact Statement (RIS) that car-to-car and pedestrian AEB should be standard on all new models launched from July 2022 and all new vehicles sold from July 2024 like in the European Union.[20] AEB systems are required on all newly introduced vehicle models from March 2023, and all models on sale in Australia from March 2025.[30]

Legal changes applicable from 2025

For HGVs and buses, new UNECE standards have been defined to improve AEB.From 2025, in the EU, those new standards will apply to new types of vehicle.[31]

Those changes were raised after crash inquiries which found some lorry drivers regularly switch off their AEB systems to drive closer to the vehicle in front. The regulation change will limit system deactivation to 15 minutes with automatic re-engagement after 15 minutes.[31]

Benefits and limitations

Benefits

A 2012 study[32] by the Insurance Institute for Highway Safety examined how particular features of crash-avoidance systems affected the number of claims under various forms of insurance coverage. The findings indicate that two crash-avoidance features provide the biggest benefits: (a) autonomous braking that would brake on its own, if the driver does not, to avoid a forward collision, and (b) adaptive headlights that would shift the headlights in the direction the driver steers. They found lane departure systems to be not helpful, and perhaps harmful, at the circa 2012 stage of development. A 2015 Insurance Institute for Highway Safety study found forward collision warning and automatic braking systems reduced rear collisions.[33]

A 2015 study based on European and Australasian data suggests the AEB can decrease rear-end collisions by 38%.[34]

In the 2016 Berlin truck attack, the vehicle used was brought to a stop by its automatic braking system.[35] Collision avoidance features are rapidly making their way into the new vehicle fleet. In a study of police-reported crashes, automatic emergency braking was found to reduce the incidence of rear-end crashes by 39 percent.[36] A 2012 study suggests that if all cars feature the system, it will reduce accidents by up to 27 percent and save up to 8,000 lives per year on European roads.[37] [38]

A 2016 US study on trucks, considering 6,000 CAS activations from over 3 million miles and 110,000 hours driving performed with year 2013 technology, find that CAS activations were the result of lead vehicle actions, such as braking, turning, switching lanes, or merging.[39]

In the UK and the US, third-party damages and costs have decreased by 10% and 40% according to some insurances.[4]

Efficiency varies depending on analysis, according to the European Commission:[40]

In April 2019, IIHS/HLDI considered real-world benefits of crash avoidance technologies, based on rates of police-reported crashes and insurance claims. Forward collision warning plus autobrake is associated with a 50% decrease in front to rear crashes and a 56% decrease in front to rear crashes with injuries, while forward collision warning alone is associated with only a 27% decrease in front to rear crashes and an only 20% decrease in front to rear crashes with injuries. The rear automatic braking is considered to have generated a 78% decrease in backing crashes (when combined with the rearview camera and parking sensor). However, repair costs with this equipment are an average of higher due to the sensors being in areas prone to damage.[41]

In Australia, AEB has been found to reduce police-reported crashes by 55 percent, rear-end crashes by 40 percent, and vehicle occupant trauma by 28 percent.[20]

A 2020 Italian study suggests AEB reduces rear-end collision by 45% based on data from event data recorders in a sample of 1.5 million vehicles in 2017 and 1.8 million in 2018, for recent vehicles.[42]

It has been estimated that ALKS could help to avoid 47,000 serious accidents and save 3,900 lives over the first decade in the United Kingdom.[43]

Limitations and safety issues

A NTSB communication suggests that some vehicle collision avoidance assist systems are not able to detect damaged crash attenuators. Therefore the vehicle may drive into the crash attenuator. The NTSB considers such a feature would be a must-have for safety with partially automated vehicles to detect potential hazards and warn of potential hazards to drivers.[44]

Inclement weather such as heavy rain, snow, or fog may temporarily inhibit the effectiveness of the systems.

In Japan, there were 72 car-reported accidents in 2018, 101 in 2018, and 80 between January and September 2019 caused by drivers placing too much confidence in automatic brakes, with 18 of them resulting in injuries or death.[45]

Unnecessary AEB

Unnecessary AEB might trigger in situations such as shadows on the road, cars parked or metal road signs on the side of the middle of a curve, steep driveways.

Features

AEB systems aim to detect possible collisions with the car in front.[46] This is performed using sensors to detect and classify things in front of the vehicle, a system to interpret the data from the sensors, and a braking system which can work autonomously.[47]

Some cars may implement lane departure warning systems.[48]

Pedestrian detection

Since 2004, Honda has developed a night vision system that highlights pedestrians in front of the vehicle by alerting the driver with an audible chime and visually displaying them via HUD. Honda's system only works in temperatures below 30 degrees Celsius (86 Fahrenheit). This system first appeared on the Honda Legend.[49]

To assist in pedestrian safety as well as driver safety, Volvo implemented a pedestrian airbag in the Volvo V40, introduced in 2012.Many more manufacturers are developing Pedestrian crash avoidance mitigation (PCAM) systems.

In the United States, the IIHS considers:.[50]

ANCAP reports

Since 2018, the ANCAP provides AEB rating and tests AEB features.[51]

The ANCAP report in its adult occupant protection section contains AEB rating taking into account AEB City from 10 to 50  km/h.

The ANCAP report in its vulnerable user protection section contains AEB rating taking into account both AEB and FCW for pedestrian and cyclists, with various speeds named "Operational from" (for instance 10 to 80  km/h) in the reports:

The ANCAP report in its safety assist section contains AEB rating taking into account the AEB interurban with various speeds named "Operational from" (for instance 10 to 180  km/h):

Reverse automatic braking

In the US by 2017, 5% of cars were capable of reverse automatic braking. This feature allows autonomous braking of the vehicle while working in the reverse direction, to avoid a reverse collision. Those systems are assessed by IIHS.[52]

See also

Notes and References

  1. Web site: Uniform provisions concerning the approval of motor vehicles with regard to the Advanced Emergency Braking Systems (AEBS) - Addendum: 130 - Regulation: 131 . United Nations . 27 February 2014 . 3 November 2019.
  2. Web site: Uniform provisions concerning the approval of motor vehicles with regard to the Advanced Emergency Braking System (AEBS) for M1 and N1 vehicles . United Nations Economic Commission for Europe . 8 . 4 February 2020 . 31 July 2020.
  3. Kanarachos . Stratis . A new method for computing optimum obstacle avoidance steering manoeuvres of vehicles . International Journal of Vehicle Autonomous Systems . 2009 . 7 . 1 . 73–95 . 10.1504/IJVAS.2009.027968 . 29 July 2015.
  4. Web site: Autonomous Emergency Braking (AEB) Frequently Asked Questions . Thatcham Research . UK . https://web.archive.org/web/20180501093131/https://www.thatcham.org/files/pdf/AEB_FAQ.pdf . 1 May 2018.
  5. Web site: Autonomous Emergency Braking . Euro NCAP . 8 June 2019.
  6. 10.3182/20130904-4-JP-2042.00104 . Improvement of Trajectory Tracking Performance in Autonomous Collision Avoidance by Steering . Ryuzo . Hayashi . Puwadech . Chatporntanadul . Masao . Nagai . IFAC Proceedings Volumes . 7th IFAC Symposium on Advances in Automotive Control . Tokyo . 4 September 2013. 46 . 21 . 410–415 .
  7. Web site: Improved Impact of Collision Avoidance by Steering Technology on Real Life Safety . Vinnova . Stockholm, Sweden . 3 November 2019.
  8. US. 4926171. Collision predicting and avoidance device for moving vehicles. Kelley. William L.. 1990-05-15.
  9. AEB Performance in the UK; A Decade of Development . Sari . Zahra . Brookes . David . Avery . Matthew . 25th International Technical Conference on the Enhanced Safety of Vehicles . Transportation Research Board . US . 5 June 2017 . 8 June 2019.
  10. Web site: Forward Collision Warning Requirements Project Final Report - Task 1 . January 2003 . National Highway Traffic Safety Administration . 29 July 2015.
  11. Web site: Written question Rear-end traffic collisions in the European Union - E-011477/2011. europa.eu. 25 January 2015.
  12. Web site: Answer to a written question - Rear-end traffic collisions in the European Union - E-011477/2011. europa.eu. 25 January 2015.
  13. Web site: Commission of the European Communities . 23 May 2008 . Annex to the proposal for a regulation of the European Parliament and of the Council concerning type-approval requirements for the general safety of motor vehicles - Impact Assessment . https://web.archive.org/web/20150623232541/http://ec.europa.eu/enterprise/sectors/automotive/files/safety/sec_2008_1908_en.pdf . 23 June 2015 . 31 March 2016.
  14. Web site: U.S. DOT and IIHS announce the historic commitment of 20 automakers to make automatic emergency braking standard on new vehicles. U.S. Department of Transportation National Highway Traffic Safety Administration. 17 March 2016. 17 March 2016.
  15. Web site: Automakers agree to make auto braking a standard by 2022.
  16. Web site: UNECE works on new standards to increase the safety of trucks and coaches.
  17. Web site: Uniform provisions concerning the approval of motor vehicles about the Advanced Emergency Braking Systems (AEBS) . United Nations . 27 February 2014 . 21 October 2019.
  18. Web site: en . Rear-end crashes go way down when cars can brake themselves . Jordan . Golson . The Verge . 27 January 2016 . 26 May 2018.
  19. Web site: By . 10 automakers fulfill automatic emergency braking pledge ahead of schedule . 2024-08-03 . IIHS-HLDI crash testing and highway safety . en.
  20. News: Government proposes mandatory AEB . Motoring . Australia . 16 October 2020 . 1 May 2021.
  21. News: U.S. to seek automated braking requirement for heavy trucks . Honolulu Star-Advertiser . US . 2021-06-11 . 2021-07-15.
  22. Web site: 10 automakers equipped most of their 2018 vehicles with automatic emergency braking . NHTSA . US . 13 March 2019 . 28 March 2019.
  23. Web site: Autobrake is good, but it could be better . Insurance Institute for Highway Safety . US . 21 February 2019 . 15 June 2019.
  24. Trusting Other Vehicles' Automatic Emergency BrakingDecreases Self-Protective DrivingYasunori Kinosada‍ ‍, Shizuoka Institute of Science and Technology, Japan,Takashi Kobayashi, and Kazumitsu Shinohara, Osaka University, Japan
  25. Web site: AEB to be Required on New Cars in Japan. 2 December 2019.
  26. Web site: Parliament approves EU rules requiring life-saving technologies in vehicles | News | European Parliament . Europarl.europa.eu . 2019-04-16 . 2020-08-31.
  27. News: Soon, all vehicles to have 'brakes with brains' . Dipak K . Dash . Times of India . 7 September 2018 . 8 June 2019.
  28. Web site: North America Publishes Report on recent Automaker Automatic Emergency Braking Commitment . JATO . 2016-06-09 . 2020-08-31.
  29. https://www.caranddriver.com/news/a60662904/federal-automatic-emergency-braking-mandate/
  30. News: Opinion: Safety should never be an 'optional extra' on a new car . Susannah . Guthrie . Drive . Australia . 2022-07-28 . 2022-08-01.
  31. Web site: ETSC welcomes higher standards for automated emergency braking systems on HGVS | ETSC.
  32. Web site: Crash avoidance features cut insurance claims . Insurance Institute for Highway Safety . US . 4 April 2015.
  33. Automatic braking reduces rear-end crashes, IIHS study finds . Automotive News . Ryan . Beene . 28 January 2016 . 10 March 2016.
  34. Web site: New study confirms real-world safety benefits of autonomous emergency braking . European Transport Safety Council . 11 July 2015 . 8 June 2019.
  35. News: Automatic brakes stopped Berlin truck during Christmas market attack . Deutsche Welle . 28 December 2016.
  36. Web site: Effectiveness of Forward Collision Warning Systems with and without Autonomous Emergency Braking in Reducing Police-Reported Crash Rates. Cicchino. Jessica. 2016. Insurance Institute for Highway Safety. https://web.archive.org/web/20160430034800/http://www.iihs.org/frontend/iihs/documents/masterfiledocs.ashx?id=2111. 30 April 2016.
  37. Web site: Euro NCAP - Autonomous Emergency Braking AEB. https://ghostarchive.org/varchive/youtube/20211221/sh0YTnWp3CI . 2021-12-21 . live. euroncapcom. 13 June 2012. YouTube.
  38. Web site: New EU legislation requires cars to include autonomous braking system.
  39. Web site: NHTSA study: Collision avoidance systems can reduce crashes . Sean . Kilcarr . Fleet Owner . 2016-06-16 . 2020-04-11.
  40. Web site: Advanced driver assistance systems 2018 . European Road Safety Observatory . 8 June 2019.
  41. Web site: Real-word benefits of crash avoidance technologies . Insurance Institute for Highway Safety . US . April 2019 . 15 June 2019.
  42. Web site: AEB systems cut rear-end collisions by 45% . European Transport Safety Council . 14 October 2020 . 1 May 2021.
  43. News: Automated system introduced to keep your car in lane . Alice . Campion . Confused . 26 August 2020 . 4 October 2020.
  44. Web site: Collision Between a Sport Utility Vehicle Operating With Partial Driving Automation and a Crash Attenuator . . California, US . HWY18FH011 . 2018-03-23 . 2020-04-10.
  45. News: Japan to make automatic-emergency braking mandatory . New Zealand . 2019-12-18 . 2022-02-13.
  46. Web site: Car Safety Feature - Auto Emergency Braking (AEB) . Howsafeisyourcar.com.au . Australia . 8 June 2019.
  47. Web site: Potential Benefits of Autonomous Emergency Braking Based on In-depth Crash Reconstruction and Simulation . National Highway Traffic Safety Administration . Robert . Anderson . Samuel . Doecke . James . Macken . 8767744 . Paper Number 13-0152 .
  48. Umar Zakir Abdul . Hamid . Current Collision Mitigation Technologies for Advanced Driver Assistance Systems–A Survey . PERINTIS eJournal . 2016 . 6 . 2 . etal. 14 June 2017.
  49. Web site: Safety - Honda's Intelligent Night Vision system . Automotive Engineer PLUS . October 2004 . https://web.archive.org/web/20080808135950/http://www.ae-plus.com/key%20topics/kt-safety-news7.htm . 8 August 2008.
  50. Effects of automatic emergency braking systems on pedestrian crash risk . Cicchino . Jessica B. . Accident Analysis and Prevention . May 2022 . 172 . 106686 . 10.1016/j.aap.2022.106686 . 35580401 . 248805604 . 10 August 2022.
  51. Web site: AEB or auto emergency braking: Not all systems are created equal . CarsGuide . Australia . 26 February 2018 . Tom . White . 8 June 2019.
  52. News: IIHS begins testing reverse automatic braking . Andrew . Krok . Roadshow . CNN . US . 22 February 2018. 8 June 2019.