In this paper, we present the feasibility of Lamb waves generation with a thin array transducer embedded inside the material. Interaction between the Lamb waves and damages is also investigated.

A comparison between two kinds of Lamb waves transducers is performed: array device bonded on the structure and another one embedded.

First of all, a one-millimeter-thick transducer has been embedded inside an isotropic material plate made of Plexiglas with a 4- millimeter thickness.

A comparison of Lamb waves generation and detection between a bonded transducer and an embedded one has been carried out. The measured parameter is the attenuation of Lamb waves, due to the damage, during the propagation in a transmission mode.

In a second step, a thinner transducer embedded inside a Plexiglass plate with a 400-micrometer thickness has been evaluated. Lamb waves propagation is compared with results obtained for the first demonstrator, and the sensibility of defect detection is assessed with an artificial defect (a 1 centimeter diameter hole).

This work is used as an input for the study of <<Smart Structures>>, and more particularly the detection of low and high speed impact occurring on aeronautic and automotive structures.