Shift-by-wire is an automotive concept or system that employs electrical or electronic connections that replace the mechanical connection between the driver's gearshift mechanism and the

transmission Transmission or transmit may refer to: Science and technology * Power transmission ** Electric power transmission ** Transmission (mechanical device), technology that allows controlled application of power *** Automatic transmission *** Manual tra ...

. Since becoming commercially available in 1996, shift-by-wire has been commonly used in

automated manual transmission The automated manual transmission (AMT) is a type of transmission (mechanics), transmission for motor vehicles. It is essentially a conventional manual transmission equipped with automatic actuation to operate the clutch and/or shift Gear train ...

and has later been implemented in

semi-automatic transmission A semi-automatic transmission is a multiple-speed Transmission (mechanics), transmission where part of its operation is Automation, automated (typically the actuation of the clutch), but the driver's input is still required to launch the vehicle f ...

and

automatic transmission An automatic transmission (AT) or automatic gearbox is a multi-speed transmission (mechanics), transmission used in motor vehicles that does not require any input from the driver to change forward gears under normal driving conditions. The 1904 ...

. Dispensing with gearshift mechanical linkages has several advantages: it reduces complexity and simplifies assembly; reduces the force required to shift gears and allows it to be customized with

haptic technology Haptic technology (also kinaesthetic communication or 3D touch) is technology that can create an experience of touch by applying forces, vibrations, or motions to the user. These technologies can be used to create virtual objects in a computer s ...

; allows for more

interior design Interior design is the art and science of enhancing the interior of a building to achieve a healthier and more aesthetically pleasing environment for the people using the space. With a keen eye for detail and a Creativity, creative flair, an ...

freedom in the placement of the gearshift mechanism; allows for automation of the engagement of the

parking brake In road vehicles, the parking brake, also known as a handbrake or emergency brake (e-brake), is a mechanism used to keep the vehicle securely motionless when parked. Parking brakes often consist of a pulling mechanism attached to a Wire rope, ...

and other functions; reduces cabin noise by eliminating the acoustic linkage between the transmission and the gear shift; and by reducing floor openings it improves the crash behavior of the vehicle. With a mechanical connection, the gearshift selector always matches the engaged transmission gear. With shift-by-wire, safety mechanisms need to be put in place. The system needs to block incorrect input and "guide" the gearshift back to a position that matches the state of the transmission in case of error. Another solution is to separate the gearshift selector from the gear indicator, meaning the driver has to visually monitor which gear is actually engaged, for instance on a display. Safety considerations require redundancy in the gearshift and transmission sensors and in the vehicle communication network.

Park by wire

A park by wire system engages the parking pawl of a transmission using electrical means, without the traditional mechanical system which involves linkages between the gear shifter and the transmission. Park-by-wire can be considered a part of a shift by wire system, as it shifts the transmission into park mode. The main components of a park by wire system include the driver interface which could be a lever, switch, or knob; an electronic control unit; and actuators which are capable of driving the parking pawl into and out of the locking position with the parking gear of the transmission.

References

{{Powertrain Automotive electronics Vehicle safety technologies Automotive transmission technologies

Park by wire

See also

References