Embedded Thin Film Sensors Based Multi-Mode Guided Wave Filter

Ultrasonic guided waves used in the diagnostic process exhibits multi-mode characteristics that make the damage detection process cumbersome. This paper presents the identification and selective filtering of multimodal Lamb wave in a composite laminate using embedded thin film sensors. A numerical approach based on finite element modeling is employed to estimate the response of embedded sensors. Using simple correlation of the sensor signal waveforms, the fundamental and higher order wave modes have been extracted from the mixed response. This technique is extendable to Rayleigh, Stoneley and Love waves.