Abstract Debonding at two components interface (f.i., skin & stringer) is a common defect of composite stiffened structures. It may result from inefficient manufacturing or impacts from foreign objects. Discontinuities within an elastic solid medium under mechanical loads may cause local anomalies in the strain field. On this basis, the current work investigates disbonding at skin/stringer interface of an aeronautical plate, generated by low/medium energy impacts. Distributed fiber optics records longitudinal strain values; data are then elaborated by a methodology using different deformation-based features providing Local High Edge Observation (LHEO) in both time and space domains. Cross correlation is implemented to improve signal to noise ratio. Proposed LHEO algorithm proves its capability to detect impact area and occurred skin-stringer debonding, without reference to applied loads or a certain baseline. A dedicated Matlab routine elaborates the output further, with the aim of visualizing and estimating impact region extension.

中文翻译：

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通过互相关分析和分布式传感评估影响区域和脱粘线检测

摘要 两构件界面（fi、蒙皮和纵梁）的脱粘是复合材料加筋结构的常见缺陷。这可能是由于制造效率低下或异物影响造成的。在机械载荷下弹性固体介质内的不连续性可能会导致应变场中的局部异常。在此基础上，目前的工作研究了由低/中能量冲击产生的航空板蒙皮/纵梁界面的脱粘。分布式光纤记录纵向应变值；然后通过使用不同的基于变形的特征的方法详细阐述数据，在时域和空间域中提供局部高边缘观测 (LHEO)。实施互相关以提高信噪比。提出的 LHEO 算法证明了其能够检测撞击区域和发生的皮肤纵梁脱粘，而无需参考施加的载荷或某个基线。一个专用的 Matlab 程序进一步阐述了输出，目的是可视化和估计影响区域的扩展。