An anti-lock braking system (commonly known as ABS, from the German name "Antiblockiersystem" given to it by its inventors at Bosch) is a system on motor vehicles which prevents the wheels from locking while braking. The purpose of this is twofold: to allow the driver to maintain steering control and to shorten braking distances. Robert Bosch GmbH is a German company founded by Robert Bosch in 1886. ... Vehicles are non-living means of transport. ... A wheel is a circular object that together with an axle allows low friction motion, e. ... Locking can refer to an act of concurrency management in software a device, used for security. ... For the type of ferns known as brakes, see brake (fern). ...

History

Anti-lock braking systems were first developed for aircraft. An early system was Dunlop's Maxaret system, introduced in the 1950s and still in use on some aircraft models. This was a fully mechanical system. It saw limited automobile use in the 1960s in the Ferguson P99 racing car, the Jensen FF and the experimental all wheel drive Ford Zodiac, but saw no further use; the system proved expensive and in automobile use somewhat unreliable. A purely mechanical system developed and sold by Lucas Girling was factory-fitted to the Ford Fiesta Mk III. It was called the Stop Control System. An aircraft is any machine capable of atmospheric flight. ... People whose family name is or was Dunlop include John Boyd Dunlop — Scottish inventor and founder of the Dunlop rubber company John Thomas Dunlop — United States administrator Sir Edward Weary Dunlop — Australian war hero Douglas Morton Dunlop — Scottish-American professor of history and orientalist. ... Centuries: 19th century - 20th century - 21st century Decades: 1900s 1910s 1920s 1930s 1940s 1950s - 1960s - 1970s 1980s 1990s 2000s 2010s Years: 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 Events and trends The 1960s was a turbulent decade of change around the world. ... The Jensen FF was an all wheel drive GT car produced by the British manufacturer Jensen between 1966 and 1971. ... Four wheel drive or 4x4, is a type of four wheeled vehicle drivetrain configuration that enables all four wheels to receive power from the engine simultaneously in order to provide maximum traction. ... Categories: Automobile stubs | Ford vehicles ...

The German firm of Bosch had been developing anti-lock braking technology since the 1930s, but the first production cars using Bosch's electronic system became available in 1978. They first appeared in trucks and German limousines from Mercedes-Benz. Systems were later introduced on motorcycles. Robert Bosch GmbH is a German company founded by Robert Bosch in 1886. ... Events and trends Technology Jet engine invented Science Nuclear fission discovered by Otto Hahn, Lise Meitner and Fritz Strassmann Pluto, the ninth planet from the Sun, is discovered by Clyde Tombaugh British biologist Arthur Tansley coins term ecosystem War, peace and politics Socialists proclaim The death of Capitalism Rise to... The driver of a car transporter truck prepares to offload Skoda Octavia cars in Cardiff, Wales For further uses of the word truck, see Truck (disambiguation). ... This page is about the Mercedes-Benz brand of automobiles and trucks from the DaimlerChrysler automobile manufacturer. ... A motorcycle (or motorbike) is a two-wheeled vehicle powered by an engine. ...

Operation

The anti-lock brake controller is also known as the CAB (Controller Anti-lock Brake).

A typical ABS is composed of a central electronic unit, four speed sensors (one for each wheel), and two or more hydraulic valves on the brake circuit. The electronic unit constantly monitors the rotation speed of each wheel. When it senses that one or more wheel is rotating slower than the others (a condition that will bring it to lock) it moves the valves to decrease the pressure on the braking circuit, effectively reducing the braking force on that wheel. Pressure (symbol: p or P) is the measure of the force that acts on a unit area. ...

Effectiveness

On high-traction surfaces such as bitumen, whether wet or dry, most ABS-equipped cars are able to attain braking distances better (i.e. shorter) than those that would be possible without the benefit of ABS. A moderately-skilled driver without ABS might be able, through the use of cadence-braking, to match the performance of a novice driver with an ABS-equipped vehicle. However, for a significant number of drivers, ABS will improve their braking distances in a wide variety of conditions. The recommended technique for non-expert drivers in an ABS-equipped car, in a typical full-braking emergency, is to press the brake pedal as firmly as possible and, where appropriate, to steer around obstructions. In such situations, ABS will significantly reduce the chances of a skid and subsequent loss of control—particularly with heavy vehicles. Bitumen Bitumen is a category of organic liquids which are highly viscous, black, sticky and wholly soluble in carbon disulfide. ...

In gravel and snow, ABS tends to increase braking distances. On these surfaces, locked wheels dig in and stop the vehicle more quickly. ABS prevents this from occurring. Some ABS controllers reduce this problem by slowing the cycling time, thus letting the wheels repeatedly briefly lock and unlock. The primary benefit of ABS on such surfaces is to increase the ability of the driver to maintain control of the car rather than go into a skid—though loss of control remains more likely on soft surfaces like gravel or slippery surfaces like snow or ice.

When activated, the ABS causes the brake pedal to pulse noticeably. As most drivers rarely or never brake hard enough to cause brake lockup, and a significant number rarely bother to read the car's manual, this may not be discovered until an emergency. When drivers do encounter an emergency that causes them to brake hard and thus encounter this pulsing for the first time, many are believed to reduce pedal pressure and thus lengthen braking distances, contributing to a higher level of accidents than the superior emergency stopping capabilities of ABS would otherwise promise. Some manufacturers have therefore implemented "brake assist" systems that determine the driver is attempting a crash stop and maintain braking force in this situation. Nevertheless, ABS significantly improves safety and control for drivers in on-road situations if they know not to release the brakes when they feel the pulsing of ABS.

It is worth noting that the heavier a vehicle is, the more it will benefit from ABS. This is particularly true of vehicles with less-sophisticated hydraulic braking systems where fine control is not as easy as with the more developed braking systems. Conversely, lighter vehicles, especially sports cars with highly-developed braking systems without ABS can outbrake comparable vehicles even with ABS A Honda NSX sports car A TVR Tuscan sports car A sports car is a car designed for sporting performance above utility. ...

Traction control

The ABS equipment may also be used to implement traction control on acceleration of the vehicle. If, when accelerating, the tire loses traction with the ground, the ABS controller can detect the situation and apply the brakes to reduce the acceleration so that traction is regained. Manufacturers often offer this as a separately priced option even though the infrastructure is largely shared with ABS. More sophisticated versions of this can also control throttle levels and brakes simultaneously, leading to what Bosch terms the "Electronic Stability Program" (ESP). Traction control and Vehicle Stability Control systems, on current production vehicles, are typically (but not necessarily) electro-hydraulic systems designed to prevent loss of control when excessive throttle or steering is applied by the driver. ... Bosch is the colloquial short name for the German company Robert Bosch GmbH, as well as the last name of: Hieronymus Bosch (1450-1516) - Dutch painter Robert Bosch (1861-1942) - German industrialist Carl Bosch (1874-1940) - German chemist and engineer Juan Bosch (1909-2001) - Dominican politician and writer This is... Electronic Stability Program (ESP), also known as Vehicle Dynamics Control (VDC), Electronic Skid Protection (ESP) and many other names, are electro-hydraulic systems that help control vehicles as they approach the limits of stability. ... ESP can mean Electronic Stability Program also known as Electronic Skid Prevention, a safety system in cars that detects the steering wheel angle, speed of each tire, yaw and direction of the car and can activate one brake at an appropriate wheel to prevent a skid before it happens. ...

See also: car safety. Car safety is the avoidance of car accidents or the minimization of harmful effects of accidents, in particular as pertaining to human life and health. ...