English, 15 pages, 15 figures, 12 references
Keywords: active safety, ESP

ESP deals with the problem of the driver loosing control of his car in extreme handling manoeuvers. The problem and the help ESP offers is described in physical terms, as well as all components used by the ESP system. From the difference between the motion intended by the driver and the actual vehicle motion, brake apply interventions at individual wheels are derived to reduce that difference. Additional engine interventions support the control. Using the new sensor signals in addition to the wheel speed signals a new ABS controller based on tire slip is designed and implemented. Thus a hierarchical control is obtained in which the superimposed vehicle motion controller passes on the required slip at each wheel to the ABS and ASR controllers. Furthermore, the functionality of the system in emergency manoeuvers is demonstrated. In case a sensor signal fails the system is switched off in a failure dependent way. Some of the failure detection features are discussed at the end of the paper.