基于移动最小二乘拟合的数字图像相关应变测量

为了应用数字图像相关方法得到可靠的位移场,本文提出应用移动最小二乘法对含噪声的位移场进行拟合,进而得到可靠的应变场。对原有的十字搜索算法进行了改进,实验表明改进后的搜索算法效率更高。用数字模拟实验验证了程序计算正确性,并说明能够应用该方法得到可靠的应变。并进行了复合材料板拉伸试验,复合材料平板实验计算结果和应变电测法得到的结果进行了对比,实验表明两种测量方法得到的结果相吻合。

Digital Image Correlation Strain Measurement Based on Moving Least-Squares Fitting

In order to obtain a reliable displacement field for digital speckle image correlation technique,a new displacement analysis method based on moving least squares analysis is proposed and a reliable strain field is obtained.The authors improve on the original cross search method and the improved search algorithm is more efficient.The validity of the suggested method and the relevant computer code were verified through the analysis of the computer-simulated speckle images.The method was also used to measure s...