Controlling the wheels - a potted history

At the time, electronics still worked on the basis of analogue technology which was relatively susceptible to failure – the progress made in the development of digital technology was still rather modest. In spite of this, Daimler-Benz introduced the first-generation anti-lock braking system for passenger cars, trucks and buses to the international public on the test track in Untertürkheim on December 12, 1970 – and automotive experts and trade press responded with enthusiasm. The principle was found to be convincing.

The road to ABS for large-scale production

Another eight years passed, however, before Daimler-Benz was able to offer a reliably functioning anti-lock braking system for large-scale production vehicles. This period was necessary to develop the engineering to full maturity and absolute reliability. In the process, the engineers benefited from a revolution in electronics: at last, digital technology permitted the production of small and robust computers which recorded the wheel sensor data in next to no time and reliably actuated the valves for regulating the brake pressure. The wheel sensors had also been simplified significantly, permitting the contactless transmission of signals from which the electronics calculated the acceleration and deceleration of the wheel.

The development of the first digital control unit for test purposes by development partner Robert Bosch GmbH took five years. This second-generation ABS at last ensured the unrestricted steerability of the vehicle even under emergency braking, thereby rendering a significant contribution to active safety.

1978: The world’s first standard-production ABS

In August 1978, Mercedes-Benz was the world’s first motor manufacturer to officially introduce the new ABS. In December 1978, ABS became optionally available, initially in the S-Class at an extra charge of DM 2,217.60. Before long, it also became available for the other model series. In 1984, ABS became standard on Mercedes-Benz passenger cars for the first time. Ten years after the launch, as many as one million Mercedes-Benz cars equipped with ABS were already operating on roads throughout the world.

Mercedes-Benz also adopted a pioneering role where commercial vehicles are concerned. As early as 1981, ABS, developed together with Messrs. Wabco, was offered for compressed-air brakes. Since 1987, ABS has been standard on all touring coaches and since 1991 on all trucks. In late 1990, ABS was also incorporated in the racing cars Mercedes-Benz entered in the German Touring Car Championships.

In the years to follow the motto was: smaller, lighter, more efficient. In 1989, the developers succeeded in fitting a hybrid-design control unit directly to the hydraulic unit, thereby dispensing with complex connections and reducing the weight of the ABS 2E generation. After that, additional functions were added, among them electronic brake power distribution which replaced the mechanical brake pressure reducer on the rear axle. The eighth ABS generation currently in use was introduced in 2001. It features a modular structure, permitting a single product family of brake control systems in different configurations: ABS, BAS, ASR and ESP.

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