PVDF film sensor and its applications in damage detection

Removable and reusable sensors are essential in applications like health mo nitoring or the nondestructive evaluation of newly produced or finished com posite structures. In such tests, a major requirement is that the tested st ructures are not altered during either bonding or removal of the sensor. In this paper, removability and reusability have been introduced to polyvinyl indine fluoride (PVDF) film sensors by a very simple process that uses doub le-sided adhesive tapes. The repeatability of signals generated by such sen sors is verified through a series of tests. The use of these removable and reusable sensors is then demonstrated through a selected application where PVDF sensors are ideally suited, namely, detection of defects such as impac t damage, saw cuts, and delaminations in elastic structures. These defects change the local curvature in beams, plates, or shell structures, and PVDF sensors are ideally suited to detect these changes in curvatures.