Automatic train operation

Panel of MTR SP1950 EMU, capable of running ATO

Automatic train operation (ATO) is an operational safety enhancement device used to help automate the operation of trains. The degree of automation is indicated by the Grade of Automation (GoA), up to GoA level 4 (where the train is automatically controlled without any staff on board). ATO is primarily used on automated guideway transit and rapid transit systems where it is easier to ensure the safety of humans. On most systems, there is a driver present to mitigate risks associated with failures or emergencies.

Many modern systems are linked with automatic train control (ATC) and, in many cases, automatic train protection (ATP) where normal signaller operations such as route setting and train regulation are carried out by the system. The ATO and ATC/ATP systems will work together to maintain a train within a defined tolerance of its timetable. The combined system will marginally adjust operating parameters such as the ratio of power to coast when moving and station dwell time in order to adhere to a defined timetable.

Types of train automation[]

A diagram representing the different levels of automation possible on railways

According to the International Association of Public Transport (UITP), there are five Grades of Automation (GoA) of trains:^[1][2]

Operation of ATO[]

Whereas ATP is the safety system which ensures a safe spacing between trains and provides sufficient warning as to when to stop, ATO is the "non-safety" part of train operation related to station stops and starts, and indicates the stopping position for the train once the ATP has confirmed that the line is clear.

The train approaches the station under clear signals, so it can do a normal run-in. When it reaches the first beacon – originally a looped cable, now usually a fixed transponder – a station brake command is received by the train. The on-board computer calculates the braking curve to enable it to stop at the correct point, and as the train runs in towards the platform, the curve is updated a number of times (which varies from system to system) to ensure accuracy.^[3]

When the train has stopped, it verifies that its brakes are applied and checks that it has stopped within the door-enabling loops. These loops verify the position of the train relative to the platform and which side the doors should open. Once all this is complete, the ATO will open the doors. After a set time, predetermined or varied by the control centre as required, the ATO will close the doors and automatically restart the train if the door closed proving circuit is complete. Some systems have platform screen doors as well. ATO will also provide a signal for these to open once it has completed the on-board checking procedure. Although described here as an ATO function, door enabling at stations is often incorporated as part of the ATP equipment because it is regarded as a "vital" system and requires the same safety validation processes as ATP.^[3]

Once door operation is completed, ATO will accelerate the train to its cruising speed, allow it to coast to the next station brake command beacon and then brake into the next station, assuming no intervention by the ATP system.^[3]

Notable examples[]

Urban passenger railways[]

The two white ATO start buttons beside the power/brake lever in a Tokyo Metro 10000 series train, corresponding to GoA 2 operation

• The Barcelona Metro's (old) line II (now L5) was the first metro line in the world to install a GoA 2 photoelectric cell-based ATO system on an existing metro line and on its FMB 600 series (ca) rolling stock. This system was implemented in 1960–1961 and decommissioned in 1970. Currently, L9 (Europe's longest driverless line), L10 and L11 run with GoA 4 ATO.
• A pilot for ATO on the London Underground saw 1960 Stock trains fitted for ATO running along the Woodford to Hainault section of the Central Line from 1964 until 1986 when the trains were reverted to manual operation. The Victoria line opened in 1968 as the world's first newly-built full scale automatic railway and metro line and has since become the first to have an ATO system replaced. The full Central, Northern, and Jubilee lines have also been upgraded to run with ATO. The Circle, District, Hammersmith & City and Metropolitan lines are currently being modernised with a brand new automatic train control system.
• The PATCO Speedline between Philadelphia, Pennsylvania and Lindenwold, New Jersey, opened its first segment in 1969 as the first ATO line in the United States. (The Expo Express, which ran during the World's Fair Expo 67 in Montreal, was the first in Canada and in North America.)
• Bay Area Rapid Transit (BART), opened in 1972, was the first new metro system with multiple lines built with ATO.
• On the MTR Network in Hong Kong, all lines operated by MTR Corporation have run with ATO since 1979. The former KCR East Rail line network has used ATO since 2002.
• The Montreal Metro Green, Orange and Blue lines have been using ATO since 1977.
• The Glasgow Subway has used ATO since 1980.
• Many trains in Japan use some level of ATO. A notable example is the Yurikamome line in Tokyo, which is GoA 4.
• The French Véhicule Automatique Léger system, initially implemented on the Lille Metro in 1983, is a fully automated GoA 4 system. Its ATO system is also used with conventional heavy rolling stock on the Paris Métro Line 14, Line 1 and Lausanne Métro line 2.
• The Vancouver SkyTrain in Vancouver, British Columbia, is an automated and driverless system commissioned in 1985.
• On the Mass Rapid Transit (Singapore), all lines operating currently run with ATO since 1987.
• All of the lines on the Docklands Light Railway in London have used ATO (GoA 3) since it opened in 1987.
• On the Nuremberg U-Bahn, existing U2 and new U3 lines were converted to ATO in 2008, with one-year mix service.^[4]
• The Tren Urbano, which serves the San Juan metropolitan area, has a Siemens ATC system that allows for fully automatic operation.^[5]
• On the Milan Metro, the M1 Red Line and the M3 Yellow Line run with ATO.^[6]
• The Washington Metro is possibly the first system in the world to revert to (mostly) manual operation from ATO, following a crash in 2009. However, GoA 2 is still installed on all lines and is planned to be used again in the future.
• The Prague Metro historically operated GoA 1 system ARS on all lines. GoA 2 is available on line C (PA 135 by Siemens) and line A (LZA by AŽD Praha). As of 2020, line B is transitioning from ARS to LZA. The projected line D should operate unattended.
• São Paulo Metrô, Line 4 was opened in 2010 as the first system operating GoA 4 in South America.
• On the New York City Subway, the BMT Canarsie Line (L train) began full ATO operation using CBTC in June 2012.^[7][8] IRT Flushing Line (7 and <7>​ trains) similarly underwent track and signal modernization, with full ATO operation beginning in November 2018.^[9]
• The trains on Dubai Metro do not have a driver, neither do the trains on AnsaldoBreda Driverless Metro and on Line C of the Rome Metro^[10]
• The trains on Doha Metro recently started operation, running automatically in ATO without a driver ^[11]
• Aerotrain (KLIA) in Kuala Lumpur, Malaysia uses a GoA 4 ATO system.
• On the Los Angeles Metro system, the B Line, D Line, and C Line use the GoA 2 ATO system.
• Indonesia's capital city, Jakarta, introduced public transport (Jakarta MRT) that uses the ATO with GoA 2 Level.
• New South Wales's capital city Sydney in Australia, has the Sydney Metro which opened in 2019 and operates with GoA Level 4. Sydney is also in the process of upgrading older lines in the network to eventually enable GoA 2 and higher in the future.
• Delhi Metro started driverless train operations in December 2020 running on GoA 4 ATO system.

Freight railways[]

• The Rio Tinto Group "AutoHaul" system on its iron ore railways in the Pilbara.^[12] This system is GoA 4 capable, able to run trains without a single person aboard for the entire trip out to the mines and back to the port. In October 2017 the first fully autonomous test took place over a 100 kilometres (62 mi) section.^[13] The group was granted accreditation by Australia's Office of the National Rail Safety Regulator, approving the autonomous operation of iron ore trains in the Pilbara region of Western Australia.^[14]
• The Iron Ore Company of Canada uses nine automated GMD SW1200MG electric locomotives. This railroad is GoA4 capable, able to run trains without a single person aboard for the entire trip out to a processing plant and back to the mine in Labrador City.
• The Navajo Mine Railroad uses four remote-controlled GE E60 electric locomotives. This railroad is GoA2 capable, able to run a train without any person on board for the entire trip out to the Four Corners Generating Station and back to the mines.

Mainline operation[]

• The Czech railways have used GoA2 operation since 1991. Currently, about 400 vehicles are equipped with on-board units.^[timeframe?] 1500 km of lines (of total 9000 km network) are equipped with lineside part of ATO, next 1500 km are covered by data for GPS localisation.
• In the United Kingdom, the Thameslink core section through Central London between St Pancras and Blackfriars became the first ATO route on the National Rail network in 2018.^[15]

High speed rails[]

• German ICE high-speed lines equipped with the Linienzugbeeinflussung (LZB) signalling system support a form of GoA 2 ATO operation called AFB (Automatische Fahr- und Bremssteuerung, lit. automatic driving and braking control) which enables the driver to let the on-board train computer drive the train on autopilot, automatically driving at the maximum speed currently allowed by LZB signalling. In this mode, the driver only monitors the train and watches for unexpected obstacles on the tracks. On lines equipped with only PZB/Indusi, AFB acts entirely as a speed cruise control, driving according to the speed set by the driver with manual braking if needed.^[16]
• CR400BF-C 'Fuxing Hao', a variant of CR400 Fuxing series, running on Beijing–Zhangjiakou intercity railway is said to be the world first high-speed rail service capable of driverless automation in commercial operations. The specific Grade of Automation (GoA) was not announced.^[17][18]

Future[]

ATO will be introduced on the London Underground's Circle, District, Hammersmith & City, and Metropolitan lines by 2022. ATO will be used on parts of Crossrail once the route opens. Trains on the central London section of Thameslink were the first to use ATO on the UK mainline railway network^[19] with ETCS Level 2.

The U-Bahn in Vienna will be equipped with ATO in 2023 on the new U5 line.

All lines being built for the new Sydney Metro will feature driverless operation without any staff in attendance.

Since 2012, the Toronto subway has been undergoing signal upgrades in order to use ATO and ATC over the next decade.^[20] Work has been completed on sections Yonge–University line.^[21] The underground portion of Line 5 Eglinton will be equipped with ATC and ATO in 2022. The underground portion will use a GoA2 system while the Eglinton Maintenance and Storage Facility will use a GoA4 system and travel driverless around the yard.^[22] The Ontario Line is proposed have a GoA4 driverless system and will open in 2030.^[23]

ATO is in everyday operation on Czech Railways lines with AVV since 1991, and in test operation with ETCS since 2008.

Delhi Metro officials have stated that driverless trains with advanced features will run on the Botanical Garden – Kalkaji corridor, with trial runs planned for the last week of July 2016 and the trains being operated on the route from August 2016 onwards. Initially, drivers will be deputed to operate the trains but will be gradually withdrawn, said a metro official.^{[24][out of date]}

Since March 2021, SNCF and Hauts-de-France region have begun an experimentation with a French Regio 2N Class, equipped with sensors and software(fr).

See also[]

• List of automated urban metro subway systems
• Automation of the London Underground
• Communications-based train control – A moving block signalling system that can be used to automate operation of trains
• One-man operation – A method of train operation, sometimes seen as an intermediate step towards greater automation
• Vehicular automation
  • Personal Rapid Transit
  • Autonomous car
  • Guided bus

References[]