摘要

Phased array theory is utilized in the unmanned aerial vehicle (UAV) wing box to identify the damage in the structure. The phased array theory has been adapted to Lamb wave propagation to improve the detection ability of local defects in the complex composite structure. The validity of the proposed method is demonstrated by experimental research in which input signals exerted at piezoelectric (PZT) actuators/sensors on the UAV wing box are successfully reconstructed by using the phased array method. The recognition result is shown on a mapped image. The original mapped image uses gray level transformation method to enhance the image identifiable degrees. And the time of arrival of the Lamb wave signal is calculated by Shannon Wavelet. The experiments is done on carbon composite structure using one dimensional PZT linear sensors array exemplifies that phased array theory well utilized in scanning and detecting the damage and the screw loosening in the structure. The original image is processed by the gray level transformation to improve the contrast and the recognition.