Principal Component Analysis of Piezo-Sensor Array for Damage Localization

摘要

This paper investigates the problem of structural health monitoring by means of an array of accelerometers or distributed piezoelectric sensors. It is well known that localized structural damage with relative small amplitude do not much affect the global modal response of the structure, at least at low frequencies. Nevertheless, it can be expected that the local dynamic behavior of a damaged structural sub-component is significantly affected. By applying a principal component analysis (PCA) on the sensor time responses (e.g.: piezoelectric laminas or accelerometers), it is possible to detect any change occurring to the subspace generated by the complete sensor response set. The subspace corresponding to the damaged structure can then be compared with the subspace of an initial state in order to diagnose and localize damage. This damage detection and localization technique is experimentally illustrated on a benchmark instrumented by accelerometers. The opportunity to apply this technique with piezo-laminate sensors is also discussed on a numerical example.