Piezopolymer Interdigital Transducers for a Structural Health Monitoring System

During the last 10 years, the structural health monitoring (SHM) technique based on Lamb waves, involving intelligent sensors spread on the structure like biological receptors on the human body, achieved good and promising results showing broad-based economic benefits. There are a few who demonstrated SHM systems based on the use of a network of piezoceramic sensors applied directly to the structure for monitoring and surveying, controlled by a dedicated control unit, the health of the structure itself (detection of cracks, delaminations, disbonds, and corrosion to monitoring the mechanical impacts on metal and composite structures, etc.). The work describes a new approach for the development of this SHM system based on flexible piezopolymer transducers (PPTs) which have some advantages over the piezoceramic thin disk transducers in space applications.