Structural adaptive damage detection under uncertainty based on probability dissimilarity and moving average control chart

For engineering applications of guided-wave-based online structural damage detection, dealing with uncertainty caused by time-varying conditions (TVCs) is an issue of fundamental importance. In this study, a structural adaptive damage detection method based on probability dissimilarity and moving average control chart (MACC) is proposed. To suppress the uncertain effects of TVCs on signals, the probability dissimilarity-based damage index (PDDI) is extracted based on the proposed adaptive probability modeling of signal feature and probability distribution dissimilarity measure. Then, the automatic damage alarm mechanism based on MACC is proposed to determine alarm threshold adaptively and restrain the uncertain influence further by the moving average of PDDI. The proposed method is verified by the damage detection experiments on typical aircraft lug specimens under varying load and temperature, and then the method is applied to the full-scale aircraft fatigue test. The results demonstrate that the proposed method realizes reliable and adaptive structural damage detection under uncertain conditions.