“…In order to detect anomalous system behavior and then isolate its causes, a general framework is developed in [3] where the information to be dealt with is the sign of the first and second derivatives of the measurements. In engine control systems, acceleration estimate, needed for protective supervision, is accomplished with differentiated velocity information (see [4], [5]). A wellknown test, used to implement control techniques for antiblock and anti-spin systems for passengers car, is the braketestbrench [6], [7] which uses an estimate of the zero orderderivative of the wheel velocity.…”