Additionally to the already available Automatic Stability Control (ASC) systems and the latest ASC systems (ASC+T) of the BMW top models, newly designed stability control systems will become introduced in the 3-series and 5-series BMW cars. All these systems are applicable on mechanic and automatic gearbox-equipped cars. Whereas ASC, available at BMW since 1987, is a pure engine-control system, the ASC+T systems of BMW additionally apply active braking to the driven wheels. The engine control of BMW's ASC systems is based on a selected interface structure of engine management and transmission control units. Throttle control and active braking are realized differently depending on the respective model range. Whereas the BMW 750i and 850i use bifluid hydraulic units in add-on technique for ASC, ABS-integrated hydraulics in open or semi-open version will be applied to the other types of the BMW model range. The different systems described show remarkable improvements in both vehicle stability and in traction capability during critical driving situations. Performance data and statistical analysis of test results obtained with ASC-equipped cars prove, that the ASC systems contribute significantly to improve active safety.
Abstract