question: How do steering wheels run the electrics for media/infotainment controls through the steering column when a steering wheel can turn multiple revolutions in both directions? Don't wires get twisted to the point of giving out?
comment: Clock spring. It’s basically a spiral of wire in the wheel rolled up loosely so it can be wound tighter or looser depending on the direction you’re turning.
passages: Other power steering systems (such as those in the largest off-road construction vehicles) have no direct mechanical connection to the steering linkage; they require electrical power. Systems of this kind, with no mechanical connection, are sometimes called "drive by wire" or "steer by wire", by analogy with aviation's "fly-by-wire". In this context, "wire" refers to electrical cables that carry power and data, not thin wire rope mechanical control cables.
   The first production vehicle to implement this was the Infiniti Q50., but after negative comments they retrofitted the traditional hydraulic steering. Its implementation in road vehicles is limited by concerns over reliability although it has been demonstrated in several concept vehicles such as ThyssenKrupp Presta Steering's Mercedes-Benz Unimog, General Motors' Hy-wire and Sequel, Saabs Prometheus and the Mazda Ryuga. A rear wheel SbW system by Delphi called Quadrasteer is used on some pickup trucks but has had limited commercial success. 
   The Swedish startup Uniti will release the Uniti all electric car in 2019 with an in-house designed steer-by-wire system and will entirely replace the steering wheel. The concept was showcased in VR at the 2016 CeBit edition.
  
  This is not to be confused with Electric Power Steering. Electric Power Steering can be considered as a stage of evolution from mechanical steering to steer by wire systems.
  
  Section::::Uses in passenger cars.:Park by wire.
   This kind of system will provide steering control to a car with fewer mechanical components/linkages between the steering wheel and the wheels. The control of the wheels' direction will be established through electric motor(s) which are actuated by electronic control units monitoring the steering wheel inputs from the driver. Such a system is illegal in most jurisdictions for passenger or commercial vehicles.
   It was invented by Citroën of France.
  
  As long as there is pressure in the car's hydraulic system, there is no mechanical connection between the steering wheel and the roadwheels. This system was first introduced in the Citroën SM in 1970, and was known as 'VariPower' in the UK and 'SpeedFeel' in the U.S.
  
  Section::::Electro-hydraulic systems.
  
  Electro-hydraulic power steering systems, sometimes abbreviated EHPS, and also sometimes called "hybrid" systems, use the same hydraulic assist technology as standard systems, but the hydraulic pressure comes from a pump driven by an electric motor instead of a drive belt at the engine.
   BULLET::::- The steering is operated by a rack and pinion system which normally only works as a feedback loop.
  
  BULLET::::- The rack takes the form of a double acting hydraulic ram, but is capable of taking over full steering function in the event of a hydraulic failure. During normal operation the rack and pinion merely provides a position indication to the steering control valve through the pinion shaft. The rack and pinion do the actual steering only in the absence of system hydraulic pressure.
   BULLET::::- syntelic: both chromatids are anchored to MTs emanating from the same pole; this situation does not generate centromeric tension either, and the spindle checkpoint will be activated. If it is not corrected, both chromatids will end in the same daughter cell, generating aneuploidy.
   In the 1980s, a Japanese electronics company, Futaba, copied wheeled steering for RC cars. It was originally developed by Orbit for a transmitter specially designed for Associated cars It has been widely accepted along with a trigger control for throttle. Often configured for right hand users, the transmitter looks like a pistol with a wheel attached on its right side. Pulling the trigger would accelerate the car forward, while pushing it would either stop the car or cause it to go into reverse. Some models are available in left-handed versions.
  
  Section::::Mass production.
   Steering wheels are used in most modern land vehicles, including all mass-production automobiles, as well as buses, light and heavy trucks, and tractors. The steering wheel is the part of the steering system that is manipulated by the driver; the rest of the steering system responds to such driver inputs. This can be through direct mechanical contact as in recirculating ball or rack and pinion steering gears, without or with the assistance of hydraulic power steering, HPS, or as in some modern production cars with the assistance of computer-controlled motors, known as Electric Power Steering.
  
  Section::::History.
   Because the steering wheel can be bypassed as an input device, safety can be improved by providing computer controlled intervention of vehicle controls with systems such as electronic stability control (ESC), adaptive cruise control and Lane Assist Systems. Some systems, with appropriate modification, allow for control by laptops or even game controllers.
  
  Ergonomics can be improved by the amount of force and range of movement required by the driver and by greater flexibility in the location of controls. This flexibility also significantly expands the number of options for the vehicle's design.
  
  Section::::Disadvantages.
   In recent years, the theme park industry has begun using AGVs for rides. One of the earliest AGV ride systems was for Epcot's Universe of Energy, opened in 1982. The ride used wired navigation to drive the 'Traveling Theatre' through the ride. Many rides use wired navigation, especially when employees must frequently walk over the ride path such as at (the now-closed attraction) The Great Movie Ride at Disney's Hollywood Studios. Another ride at Hollywood Studios that uses wired navigation is The Twilight Zone Tower of Terror, a combined drop tower/dark ride. The elevator cars are AGVs that lock into place inside separate vertical motion cab to move vertically. When it reaches a floor requiring horizontal movement, the AGV unlocks from the vertical cab and drives itself out of the elevator.
   BULLET::::- A newer method, the Floor Pick-Up (FPU) system, uses alternating strips of metal across the floor separated by insulating spacers, and no ceiling grid. The alternating strips carry the supply current, and the cars are large enough so that the vehicle body can always cover at least two strips at any one time. An array of brushes under each car make random contact with whatever strip is below, and the voltage polarity on each contact is sorted out to always provide a correct and complete circuit to operate the vehicle.
   Electric power steering systems appeared on the Honda NSX in 1990,The MG F, the FIAT Punto Mk2 in 1999, the Honda S2000 in 1999, Toyota Prius in 2000[15], the BMW Z4 in 2002, and the Mazda RX-8 in 2003.
  
  The first electric power steering system appeared on the Suzuki Cervo in 1988. The system has been applied by various automobile manufacturers.
  
  Section::::Electric systems.:Electrically variable gear ratio systems.
   Many modern cars use rack and pinion steering mechanisms, where the steering wheel turns the pinion gear; the pinion moves the rack, which is a linear gear that meshes with the pinion, converting circular motion into linear motion along the transverse axis of the car (side to side motion). This motion applies steering torque to the swivel pin ball joints that replaced previously used kingpins of the stub axle of the steered wheels via tie rods and a short lever arm called the steering arm.
   However, during the anchoring process some incorrect configurations may also appear:
  
  BULLET::::- monotelic: only one of the chromatids is anchored to MTs, the second kinetochore is not anchored; in this situation, there is no centromeric tension, and the spindle checkpoint is activated, delaying entry in anaphase and allowing time for the cell to correct the error. If it is not corrected, the unanchored chromatid might randomly end in any of the two daughter cells, generating aneuploidy: one daughter cell would have chromosomes in excess and the other would lack some chromosomes.
   Drive by wire systems can be "hacked", and their control faulted or shut off, by either wired or wireless connections.
  
  Each drive-by-wire system leads to more motors in the vehicle and therefore a greater energy consumption. For instance, the drive-by-wire technology adds actuator motors to create the torque needed to turn the wheels, and a feedback transducer to create the "road feel" on the steering wheel.
   Other systems for steering exist, but are uncommon on road vehicles. Children's toys and go-karts often use a very direct linkage in the form of a bellcrank (also commonly known as a Pitman arm) attached directly between the steering column and the steering arms, and the use of cable-operated steering linkages (e.g. the capstan and bowstring mechanism) is also found on some home-built vehicles such as soapbox cars and recumbent tricycles.
  
  Section::::Land vehicle steering.:Power steering.
   An alternative form of electro-magnetic coupling is called a linear motor, first developed by Professor Eric Laithwaite at Imperial College London in the 1960s.
  
  Instead of supplying electric motors with power directly or charging on-board batteries, the RPEV is fitted with magnets which are impelled horizontally in the same way as the rotor on an ordinary electric motor is impelled to rotate. A linear motor works in exactly the same way a round motor which has been split to its centre, laid flat and extended.
   Section::::Mechanical Description.:On the OLEV.
  
  Attached beneath the vehicle, are "pick-up" modules, or the secondary coils, that consist of wide W-shaped ferrite cores with wires wrapped around the center. When the pick-ups "pick up" the flux from the primary coils, each pick-up gains about 17 kW of power from the induced current. This power is sent to the electric motor and battery through a regulator (a managing device that can distribute power based on need), thereby charging the OLEV wirelessly.
  
  Section::::Models.
   Compared to other drive mechanisms, the linear motor is typically maintenance-free. The pole faces on the track and moving plate attached to the car do not need to touch, and the gap between them can be quite wide to accommodate any side-to-side car motion, so there is no friction or wear between them. Further, the magnetic coil assembly on the driving pole plates are either potted or sealed in a weathertight enclosure, so that rain, vibration, and dust do not affect motor performance or cause drive motor slippage.
  
  Section::::Common elements.:On-ride camera.
   Linear induction motor technology is also used in some launched roller coasters. At present it is still impractical on street running trams, although this, in theory, could be done by burying it in a slotted conduit.
  
  Outside of public transportation, vertical linear motors have been proposed as lifting mechanisms in deep mines, and the use of linear motors is growing in motion control applications. They are also often used on sliding doors, such as those of low floor trams such as the Citadis and the Eurotram.
   As of 2007 there are no production cars available that rely solely on steer-by-wire technology due to safety, reliability and economic concerns, but this technology has been demonstrated in numerous concept cars and the similar "fly-by-wire" technology is in use in both military and civilian aviation applications. Removing the mechanical steering linkage in road going vehicles would require new legislation in most countries.
  
  Section::::Land vehicle steering.:Safety.
   Section::::Remote control applications.:Cars.
  
  ESCs designed for sport use in cars generally have reversing capability; newer sport controls can have the reversing ability overridden so that it can not be used in a race. Controls designed specifically for racing and even some sport controls have the added advantage of dynamic braking capability. The ESC forces the motor to act as a generator by placing an electrical load across the armature. This in turn makes the armature harder to turn, thus slowing or stopping the model. Some controllers add the benefit of regenerative braking.
  
  Section::::Remote control applications.:Helicopters.
   Passenger automobile regulations implemented by the U.S. Department of Transportation required the locking of steering wheel rotation (or transmission locked in "park") to hinder motor vehicle theft; in most vehicles, this is accomplished when the ignition key is removed from the ignition lock. See steering lock.
  
  Section::::Passenger cars.:Other designs.
  
  The driver's seat, and therefore the steering wheel, is centrally located on certain high-performance sports cars, such as the McLaren F1, and in the majority of single-seat racing cars.
   In this power steering system, the force steering the wheels comes from the car's high pressure hydraulic system and is always the same no matter what the road speed is. Turning the steering wheel moves the wheels simultaneously to a corresponding angle via a hydraulic cylinder. In order to give some artificial steering feel, there is a separate hydraulically operated system that tries to turn the steering wheel back to centre position. The amount of pressure applied is proportional to road speed, so that at low speeds the steering is very light, and at high speeds it is very difficult to move more than a small amount off centre.
  
presuppositions: Steering wheels should not be able to turn multiple revolutions in both directions without twisting the wire.
corrections: A clock spring allows it be wound tighter or looser depending on the direction you are turning.
raw_presuppositions: Steering wheels should not be able to turn multiple revolutions in both directions without twisting the wire. wires get twisted to the point of giving out
raw_corrections: A clock spring allows it be wound tighter or looser depending on the direction you are turning. A clock spring lets it be wound tighter or looser depending on the direction you are turning.