Random Errors in Digital Image Correlation Due to Matched or Overmatched Shape Functions
Random Errors in Digital Image Correlation Due to Matched or Overmatched Shape Functions
复制标题
由于形状函数匹配或过度匹配而导致的数字图像相关随机误差
DOI：
10.1007/s11340-015-0080-7
复制
发表时间：
2015-11-01
影响因子：
2.4
通讯作者：
Pan, B.
中科院分区：
文献类型：
--
作者：
Wang, B.;Pan, B.
研究了基于子集的数字图像相关算法中由于匹配或过匹配形状函数的使用而产生的随机误差。可以定量预测这些随机误差的执政配方。理论结果表明，这些随机误差与散斑图像的噪声水平成线性关系，与被询问子集的子集强度梯度的平方和成反比。然而，对于匹配或过匹配的情况下，零阶和一阶形状函数引起的随机误差的大小相同，而二阶形状函数引起的随机误差约为常规使用的一阶形状函数引起的随机误差的两倍。通过数值试验验证了理论公式的正确性，并与已有的实验结果进行了比较。
The random errors of subset-based digital image correlation due to the use of matched or overmatched shape functions are investigated. Governing formulations that can quantitatively predict these random errors are derived. Theoretical results reveal that all these random errors are in linear proportion to the noise level of the speckle images and inverse proportion to the sum of square of subset intensity gradients of the interrogated subsets. However, for matched or overmatched cases, zero-order and first-order shape functions give rise to the same magnitude of random errors, while the random errors induced by second-order shape functions are approximately twice that resulted from the regularly used first-order shape functions. The correctness of the derived theoretical formulations is verified using numerical tests, and also shows good accordance with previously reported experimental results.