Editing Automatic transmission (section)

==Automated manual transmission (AMT)==
{{Main|Automated manual transmission}}
''Automated manual transmission (AMT)'', sometimes referred to as a ''clutchless manual'', is a type of multi-speed [[automobile]] [[transmission (mechanics)|transmission system]] that is closely based on the mechanical design of a conventional [[manual transmission]], and automates either the clutch system, the gear shifting, or both simultaneously, requiring partial, or no driver input or involvement.<ref name="NAP"/><ref>{{cite journal |title=Research on Accurate Engagement Control of Electrohydraulic Clutch Actuator |url=https://www.sae.org/publications/technical-papers/content/2005-01-1787/ |website=www.sae.org |series=SAE Technical Paper Series |access-date=26 July 2020 |language=en |date=11 April 2005|doi=10.4271/2005-01-1787 |last1=Yulong |first1=Lei |last2=Hua |first2=Tian |volume=1|url-access=subscription }}</ref><ref>{{cite web |title=Transmission Actuation |url=https://www.fte-automotive.com/fileadmin/user_upload/Valeo_Getriebe_EN_web.pdf |website=www.fte-automotive.com |access-date=26 July 2020 |archive-date=3 November 2022 |archive-url=https://web.archive.org/web/20221103071423/https://www.fte-automotive.com/fileadmin/user_upload/Valeo_Getriebe_EN_web.pdf |url-status=dead}}</ref><ref>{{Cite web|url=https://www.repairsmith.com/i/blog/manual-vs-automatic-transmission-shift-know-about/|title=Manual vs Automatic Transmission: A Shift to Know About {{pipe}} RepairSmith Blog|date=May 6, 2020}}</ref>

Earlier versions of these transmissions that are [[Semi-automatic transmission|semi-automatic]] in operation, such as ''[[Autostick#Volkswagen Autostick|Autostick]]'', control only the [[clutch]] system [[Automation|automatically]] — and use different forms of actuation (usually via an [[actuator]] or [[Servomechanism|servo]]) to automate the clutch, but still require the driver's input and full control to manually actuate gear changes by hand. Modern versions of these systems that are fully automatic in operation, such as ''[[Selespeed]]'' and ''[[Easytronic]]'', require no driver input over gear changes or clutch operation. Semi-automatic versions require only partial driver input (i.e., the driver must change gears manually), while fully automatic versions require no manual driver input, whatsoever ([[Transmission control unit|TCU]] or [[Electronic control unit|ECU]] operates both the clutch system and gear shifts automatically).

Modern automated manual transmissions (AMT) have their roots and origins in older [[clutchless manual]] transmissions that began to appear on mass-production automobiles in the early 1930s and 1940s, prior to the introduction of hydraulic automatic transmissions. These systems were designed to reduce the amount of clutch or gear shifter usage required by the driver.<ref>{{Cite web|url=https://www.caranddriver.com/research/a31862769/how-does-an-automatic-transmission-work/|title=How Does an Automatic Transmission Work?|first=Hearst Autos|last=Research|date=April 13, 2020|website=Car and Driver}}</ref> These devices were intended to reduce the difficulty of operating conventional [[Non-synchronous transmission|unsynchronised manual transmissions]] ("crash gearboxes") that were commonly used at the time, especially in stop-start driving. An early example of this transmission was introduced with the [[Hudson Commodore]] in 1942, called ''Drive-Master''. This unit was an early [[semi-automatic transmission]], based on the design of a conventional manual transmission, which used a [[Servomechanism|servo]]-controlled [[vacuum]]-operated clutch system, with three different gear shifting modes, at the touch of a button; manual shifting and manual clutch operation (fully manual), manual shifting with automated clutch operation (semi-automatic), and automatic shifting with automatic clutch operation (fully automatic).<ref>{{Cite web |url=https://auto.howstuffworks.com/1941-1947-hudson3.htm |title=1942 Hudson {{pipe}} HowStuffWorks |access-date=2020-11-25 |archive-date=2020-08-12 |archive-url=https://web.archive.org/web/20200812072455/https://auto.howstuffworks.com/1941-1947-hudson3.htm |url-status=dead}}</ref><ref>{{cite web |url=http://hudsonterraplane.com/tech/other/DrivemasterServiceInformation.pdf |title=Hudson Drive-Master Service Information |publisher=Hudson Motor Car Company |location=Detroit, Michigan |access-date=9 July 2021 |url-status=live|archive-url=https://web.archive.org/web/20160319034651/http://www.hudsonterraplane.com/tech/other/DrivemasterServiceInformation.pdf |archive-date=2016-03-19}}</ref><ref>{{Cite web |url=https://auto.howstuffworks.com/1950-hudson-commodore.htm |title=1950 Hudson Commodore {{pipe}} HowStuffWorks |access-date=2020-11-25 |archive-date=2020-10-23 |archive-url=https://web.archive.org/web/20201023002530/https://auto.howstuffworks.com/1950-hudson-commodore.htm |url-status=dead}}</ref> Another early example of this transmission system was introduced in the 1955 [[Citroën DS]], which used a 4-speed ''BVH'' transmission. This semi-automatic transmission used an automated clutch, which was [[Hydraulic actuator|actuated using hydraulics]]. Gear selection also used [[Hydraulic machinery|hydraulics]], however, the gear ratio needs to be manually selected by the driver. This system was nicknamed ''Citro-Matic'' in the U.S.

The first modern AMTs were introduced by [[BMW]] and [[Ferrari]] in 1997, with their ''SMG'' and ''F1'' transmissions, respectively.<ref>{{Cite web|url=https://magazine.ferrari.com/en/cars/2020/04/24/news/the-ferrari-automated-gearbox-from-f1-to-ferrari-roma-79244/|title=Gearing Up|website=magazine.ferrari.com}}</ref><ref>{{Cite web|url=https://europe.autonews.com/article/19970804/ANE/708040768/ferrari-launches-f1-style-gearbox-on-f355|title=FERRARI LAUNCHES F1-STYLE GEARBOX ON F355|date=August 4, 1997|website=Automotive News Europe}}</ref><ref>{{Cite web|url=https://europe.autonews.com/article/19970609/ANE/706090799/magneti-marelli-transmission-from-f1|title=MAGNETI MARELLI: TRANSMISSION FROM F1|date=June 9, 1997|website=Automotive News Europe}}</ref> Both systems used [[hydraulic actuator]]s and [[Solenoid valve|electrical solenoids]], and a designated [[transmission control unit]] (TCU) for the clutch and shifting, plus steering wheel-mounted paddle shifters, if the driver wanted to change gear manually.

Modern fully automatic AMTs, such as ''[[Selespeed]]'' and ''[[Easytronic]]'', have now been largely superseded and replaced by the increasingly widespread [[dual-clutch transmission]] design.