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Automatic transmission
An automatic transmission (AT) or automatic gearbox is a multi-speed transmission used in motor vehicles that does not require any input from the driver other than throttle position to change forward gears under normal driving conditions.
The 1904 Sturtevant "horseless carriage gearbox" is often considered to be the first true automatic transmission.[failed verification] The first mass-produced automatic transmission is the General Motors Hydramatic four-speed hydraulic automatic, which was introduced in 1939.[citation needed]
Automatic transmissions are especially prevalent in vehicular drivetrains, particularly those subject to intense mechanical acceleration and frequent idle/transient operating conditions; commonly commercial/passenger/utility vehicles, such as buses and waste collection vehicles.
Vehicles with internal combustion engines, unlike electric vehicles, require the engine to operate in a narrow range of rates of rotation, requiring a gearbox, operated manually or automatically, to drive the wheels over a wide range of speeds.
Globally, 43% of new cars produced in 2015 were manual transmissions, falling to 37% by 2020. Automatic transmissions have long been prevalent in the United States, but only started to become common in Europe much later. In Europe in 1997, only 10–12% of cars had automatic transmissions.
In 1957 over 80% of new cars in the United States had automatic transmissions. Automatic transmissions have been standard in large cars since at least 1974. By 2020 only 2.4% of new cars had manual transmissions. Historically, automatic transmissions were less efficient, but lower fuel prices in the US made this less of a problem than in Europe.
In the United Kingdom, a majority of new cars have had automatic transmissions since 2020. Several manufacturers including Mercedes and Volvo no longer sell cars with manual transmissions. The growing prevalence of automatic transmissions is attributed to the increasing number of electric and hybrid cars, and the ease of integrating it with safety systems such as Autonomous Emergency Braking.
The efficiency (power output as a percentage of input) of conventional automatic transmissions ranges from 86 to 94%. Manual transmissions are more fuel efficient than all but the newest automatic transmissions due to their inherently low parasitic losses (typically of about 4%) in addition to being cheaper to make, lighter, better performing, and of simpler mechanical design. Fuel economy worsens with lower efficiency. However, manual transmissions require the driver to operate the clutch and change gear whenever required.
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Automatic transmission AI simulator
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Automatic transmission
An automatic transmission (AT) or automatic gearbox is a multi-speed transmission used in motor vehicles that does not require any input from the driver other than throttle position to change forward gears under normal driving conditions.
The 1904 Sturtevant "horseless carriage gearbox" is often considered to be the first true automatic transmission.[failed verification] The first mass-produced automatic transmission is the General Motors Hydramatic four-speed hydraulic automatic, which was introduced in 1939.[citation needed]
Automatic transmissions are especially prevalent in vehicular drivetrains, particularly those subject to intense mechanical acceleration and frequent idle/transient operating conditions; commonly commercial/passenger/utility vehicles, such as buses and waste collection vehicles.
Vehicles with internal combustion engines, unlike electric vehicles, require the engine to operate in a narrow range of rates of rotation, requiring a gearbox, operated manually or automatically, to drive the wheels over a wide range of speeds.
Globally, 43% of new cars produced in 2015 were manual transmissions, falling to 37% by 2020. Automatic transmissions have long been prevalent in the United States, but only started to become common in Europe much later. In Europe in 1997, only 10–12% of cars had automatic transmissions.
In 1957 over 80% of new cars in the United States had automatic transmissions. Automatic transmissions have been standard in large cars since at least 1974. By 2020 only 2.4% of new cars had manual transmissions. Historically, automatic transmissions were less efficient, but lower fuel prices in the US made this less of a problem than in Europe.
In the United Kingdom, a majority of new cars have had automatic transmissions since 2020. Several manufacturers including Mercedes and Volvo no longer sell cars with manual transmissions. The growing prevalence of automatic transmissions is attributed to the increasing number of electric and hybrid cars, and the ease of integrating it with safety systems such as Autonomous Emergency Braking.
The efficiency (power output as a percentage of input) of conventional automatic transmissions ranges from 86 to 94%. Manual transmissions are more fuel efficient than all but the newest automatic transmissions due to their inherently low parasitic losses (typically of about 4%) in addition to being cheaper to make, lighter, better performing, and of simpler mechanical design. Fuel economy worsens with lower efficiency. However, manual transmissions require the driver to operate the clutch and change gear whenever required.