Nonparametric kernel smoothing for model-free fault symptom generation

This paper describes some new developments to a recently proposed approach to the generation of fault symptoms in dynamic systems. The method is model-free, in the sense that no analytical model of the plant is needed. The kernel-smoother makes it possible to detect changes in the plant dynamics, possibly due to some malfunction. A simple sufficient condition for fault detectability is presented and an application example is given, showing the effectiveness of the proposed method.