Abstract
Structural health monitoring for identification of the impact loading, detection of the structural damage and assessment of the severity of the damage ensures safety operation of the industrial mechanical system. Author's research group demonstrated impact identification capability of time reversal processing by using experimentally measured sensor output signals. A model based impact identification method using experimentally measured sensor signals from nine surface bonded PZT sensors on a rectangular aluminum plate was presented. The time-reversed wave traveled back through the plate and was focused on the region around a point where had been hit by the impact hammer in backward process. In this study, the effect of time duration of the measured sensor signal to the impact identification capability of time reversal processing method is experimentally demonstrated. The illustrative experimental and numerical processes demonstrated the impact identification capability of time reversal processing method. Even if the measured signals were missing the wave front induced by the impact, the signal to noise ratio of the backward process was successfully improved by using the long time duration of the measured sensor signals.
