In the context of modern high performance composite materials, as used in aircraft structures, impact loadings with foreign objects are a constant risk. Impacts may occur due to falling rocks, dropped tools, bird strike etc.. As a result debondings of adjoining plies (delaminations) may occur that degrade severely the mechanical properties until structural failure occurs. Hence it is desirable to monitor the “health” of the structure permanently to get information about its integrity. The classical procedure of visual inspection is very labour- and cost intensive. The object is to develop a procedure that uses piezo-ceramic actuators and sensors to excite the structure and to measure the system response, respectively. The large amount of data will be analysed by specific programmed algorithms. The structure with sensors, actuators and computer mimics a biological system. So the technical system becomes an intelligent structure that is able to perform a self-diagnosis and to make a decision on the structure’s health conditions. In the case of damage it is able to induce a maintenance. The procedure is investigated on a CFRP plate with stringers. |
