ABS – a success story

The antilock braking system first brought to market by Bosch in 1978 prevents wheel lock during full braking. This ensures that the vehicle can still be steered and moved out of the way of unexpected obstacles.

“ABS substantially improves driving stability and usually shortens the brake path as well,” says Wolfgang Drees, member of the management board at Robert Bosch GmbH and head of its Chassis Systems division. Today, more than two thirds of all new vehicles manufactured worldwide are equipped with ABS.

Bosch filed a patent application for an “Apparatus for preventing lock-braking of the wheels of a motor vehicle” as early as 1936.

In 1978 Bosch was the world’s first automotive supplier to present an ABS system ready for mass production. By October that year, the ABS 2 was available on the market for the first time in S-Class cars from Mercedes-Benz. Integration in the BMW 7 series followed in December.

Since the components of the system had been cut to 140, its micro-electronics now displayed the reliability needed in cars.

In the following years, the main aim was to make the system smaller, lighter and more effective. In 1989, Bosch engineers successfully installed a control device built on the hybrid construction principle directly on the hydraulic aggregate. Complex connections were no longer required, and this generation of the ABS 2E was also far lighter.

In 1993 Bosch developers built the generation 5.0 with new magnetic valves. It was followed by the 5.3 and 5.7 versions. Additional functions were added, e.g. electronic brake force metering which replaced the mechanical brake force proportioning valve on the rear axle.

The current ABS generation is the ABS 8 introduced by Bosch in 2001. This is a modular system which permits the ABS, TCS and ESP® braking control systems to be implemented as an integrated product family. This has resulted in optimal use of synergies in production and development.

These technological advances have led to higher performance, less components and lower weight of the ABS. Whereas the ABS 2 (1978) weighed 6.3 kg, the ABS 8.0 of 2003 weighs a mere 1.6 kg.

Since production-line manufacturing of ABS took off in 1978, Bosch has delivered 100 million ABS systems worldwide.

Soon, no new car in Europe is to come without an antilock braking system. The European federation of automotive manufacturers has committed itself to fitting all news cars sold in Europe with ABS as standard from mid-2004 onwards.

Use in TCS and ESP®

Along with the technological advances of the ASB, Bosch also expanded the entire function range of Bosch brake control systems. On the basis of ABS, Bosch brought the first traction control system (TCS) for motor cars to mass production in 1986. It prevents wheel slip, permitting cars to accelerate better on slippery ground with improved traction (accelerative force) and driving safety. When bends are driven too fast, the system also improves driving stability by reducing drive torque.

The Electronic Stability Program (ESP®) was first brought to market by Bosch in 1995. It improves vehicle stability not only in braking and accelerating, but in all driving situations, and incorporates ABS and TCS.

If a car threatens to skid, ESP® cuts engine performance and brakes individual wheels, thereby improving driving safety considerably.

Development milestones

1936
Bosch is awarded a patent for an “Apparatus for preventing lock-braking of wheels in a motor vehicle”.

1978
Start of production-line installation of the first antilock braking system ABS 2 in Mercedes-Benz and then BMW vehicles.

1981
Delivery of the 100,000th ABS; ABS now also fitted in trucks.

1985
First ABS systems from Bosch are installed in US vehicles.

1986
One million Bosch ABS delivered.

1987
Start of mass production of the TCS traction control system for passenger cars.

1989
With the ABS 2E, the control device is installed directly on the hydraulic aggregate.

1992
10 million ABS from Bosch.

1993
Manufacturing of the ABS 5.0 begins.

1995
ABS 5.3 from Bosch starts mass production (with connected control device in micro-hybrid construction); serial manufacturing of the Electronic Stability Program (ESP®) starts.

1998
Bosch begins manufacturing the ABS 5.7.

1999
50 million ABS from Bosch.

2000
60 percent of all new cars worldwide are equipped with ABS.

2001
Start of mass production of ABS 8 from Bosch.

2003
25th anniversary of ABS mass production; 100 million ABS from Bosch.