When was abs developed?

The development of ABS system can be traced back to the beginning of last century, and the theory of anti-lock braking was put forward as early as 1928. In 1930s, mechanical anti-lock braking system was applied in trains and airplanes, and Bosch was the first to obtain the patent of anti-lock braking system with electromagnetic wheel speed sensor in 1936. In 1950s, more and more attention was paid to the automobile anti-lock braking system. In 1954, Ford relocated the aircraft's anti-lock braking system to Lincoln, and in 1957, Kelser Hayes conducted an experimental study on the anti-lock braking system named "automatic". The results show that the anti-lock braking system can really prevent the car from losing direction control during braking and shorten the braking distance. During this period, Chrysler also carried out experimental research on the anti-lock braking system named "SKIDCONTROL". Because all kinds of anti-lock braking systems in this period adopted mechanical brake pressure adjusting devices with mechanical wheel speed sensors, the wheel speed signals obtained were not accurate enough, the timeliness and accuracy of brake pressure adjustment were difficult to guarantee, and the control effect was not ideal. With the development of electronic technology, it is possible to develop an electronically controlled anti-lock braking system. In the late 1960s and early 1970s, some electronically controlled anti-lock braking systems began to enter the production stage. 1968, Kelser Hayes developed and produced a two-wheel anti-lock braking system called "SURETRACK". This system is equipped by Ford Company on Thunderbird (1969). By controlling the vacuum-driven brake pressure regulator, the brake pressure of the rear brake wheel cylinder is adjusted according to the rear wheel speed signal input by the electromagnetic speed sensor. The system named "SURE-TRACK" developed by Chrysler and Bendiks can prevent four wheels from locking due to braking. 197 1 year, equipped with royal vehicles. Its structural principle is basically the same as Kelser Hayes's "reliable orbit". The only difference between them is that there are two or four wheels. During this period, Bosch and TEVES also developed their first generation of electronic anti-lock braking system. These two kinds of anti-lock braking systems are controlled by the electromagnetic valve installed in the brake pipeline by the electronic control device, and the pressure of each brake wheel is directly adjusted by the electronic control. 197 1 year, Buick developed an anti-lock braking system, which automatically interrupted the engine ignition through an electronic control device to reduce the engine output torque and prevent the driving wheel from slipping. 1975, in cooperation with Mercedes-Benz, Webber equipped an anti-lock braking system for the first time on a freight car with pneumatic braking. The first anti-lock braking system ABS (Anti-lock Braking System) came out in 1950, which was first applied to aircraft in aviation field. 1968 began to be used in automobiles. In 1970s, the application of ABS in automobiles was promoted because the front wheels or front and rear wheels of new cars produced in seven European and American countries began to adopt disc brakes. After 1980, computer-controlled ABS gradually expanded rapidly in cars in Europe, America, Asia and Japan. So far, some high-end luxury cars, such as Mercedes-Benz, BMW, Yadea, Porsche and Opel in West Germany, Rolls-Royce, Jetta, Lu Hua, Bentley, Ferrari in Italy, Porsche in France, TX3, 300Z and Red Comet in Ford of the United States, Emgrand, Baron and Dodge in Chrysler of new york. By 1993, 46% of ABS has been installed in cars in the United States, and now nearly 75% of cars produced around the world use ABS.