Design of optimal configuration for generating A0 Lamb mode in a composite plate using piezoceramic transducers

This work concerned a technique for a health monitoring system based on the generation and sensing of Lamb waves, in composite structures by thin surface-bonded piezoceramic transducers. The objective was to develop transducers that are adapted for the damage detection in orthotropic composites. The key problem with the investigated Lamb waves was to select a mode to he sensitive to the damage. A hybrid modeling technique was therefore used to conceive transducers that were adapted to achieve such a feature. This modeling technique enabled Studying the influence of the transducer characteristics on the Lamb waves propagating in orthotropic plates, It was demonstrated that a Lamb mode could be generated dominantly to other modes by using a multi-element transducer. The effectiveness of this technique Was successfully verified experimentally on composite plates. It was shown that the dominant Lamb mode, obtained by use of dual-element transducers, was an appropriate mode for successfully detecting a damage in composites. (C) 2002 Acoustical Society of America.