点阵夹芯梁多缺陷参数的相图特征识别方法

Phase Diagram Feature Recognition Method for Multi Defect Parameters of Lattice Sandwich Beam

针对金字塔型点阵夹芯梁出现的蒙皮呼吸裂纹和芯层内部缺陷,提出一种基于相图几何特征的缺陷参数识别方法。采用超谐共振频率激励下得到的相图,利用垂线将相图分割为左右两部分,并通过图像处理方法分别计算两部分的面积,定义右侧面积与左侧面积之比为缺陷的识别指标。分析了蒙皮裂纹位置、深度及芯层缺陷位置的变化对识别指标的影响并用指标的散点图识别出点阵夹芯梁的缺陷参数。数值算例结果表明,所提方法可同时识别蒙皮裂纹位置、深度及芯层缺陷位置。

In order to detect the skin breathing crack and inner defect of core layer of pyramid truss core sandwich beam, an identification method based on phase diagram geometric feature is proposed. The phase diagram was divided into left and right parts by vertical line, and the area of the two parts was calculated by an image processing method. The ratio of right area to left area was defined as defect identification index. The influence of the position and depth of the skin crack and the position of the core layer defect on the identification index was analyzed, and the defect parameters of the sandwich beam were identified by the scatter diagram of the index. The results of numerical examples show that the method can identify the position and depth of skin cracks and the position of core defects simultaneously.