100 REPRINTED FROM: IEEE TRANS. ON INSTRUM. MEAS. Signal Interpretation for Monitoring and Diagnosis,

Abstract—This paper discusses a method for fault detection and isola-tion in continuous dynamic systems. A key aspect of this approach is the coupling of a qualitative diagnosis engine and a monitoring system that computes symbolic feature values through a signal-to-symbol transforma-tion on the continuously sampled measurement data. Signal analysis tech-niques with a sound statistical basis are employed to generate reliable sym-bolic data. The methodology is evaluated on the diagnosis of engineered faults in the cooling system of an automobile engine that has been instru-mented with temperature and pressure sensors. Results show the interde-pendency between modeling for diagnosis and the feature extraction sys-tem. Index Terms—Fault diagnosis, feature extraction, instrumentation, monitoring, symbolic signal analysis, transient analysis. I