Automatic transmissions lower the complexity of driving, removing a barrier of entry. They also allow drivers to focus on the road rather than worries about shifting gears. Automatics vastly simplify driving though, in many countries, drivers who take their test with an automatic transmission may only drive using automatic transmission.
Thomas Sturtevant’s automatic transmission system, invented in 1904, used weights and centrifugal force to shift gears. No sooner did he announce it complete than it literally fell apart.
Eventually, Alfred Munro created and patented his system but never commercialized it.
Independent inventor Oscar Banker created the first automatic transmission that worked. No sooner did he announce it perfected than he started a years-long battle with automakers. Eventually, GM purchased his invention. Banker was a serial inventor who also created the inoculation gun and the controls for a helicopter.
Finally, Hydra-Matic became the first commercialized automatic transmission, developed in 1939 General Motors. The Hydra-Matic inventor is unclear and it may be largely from Banker’s system. However, historians disagree about how much, if any, of Banker’s transmission was included in the final design.
Unlike much of the world, 96% of the cars in the United States have automatic transmissions. Manual transmissions are reserved more as a novelty or for racecars.
Automatic transmissions used to be less fuel-efficient than manual transmissions but, thanks largely to computerized shifting, the disparity has all but disappeared. Furthermore, outside of professional racetracks, automatic transmissions accelerate at roughly the same speed as manual transmissions cars.
Due to their design, all known hybrid cars are automatic transmissions. Manual transmission wouldn’t work because the clutch would disengage the engine when the car was supposed to be recapturing energy from momentum. Electric cars do not have gears; the electric motor controls the wheels at any speed. However, this radically different design mimics an automatic transmission.