DIC应变测量的局部平滑去噪算法研究

Research on Local Smoothing and Denoising Algorithm of DIC Strain Measurement

利用计算机生成模拟散斑图,选择数字图像相关DIC的非均匀变形二阶形函数计算Newton-Rapson法求解位移场引入的噪声,分析DIC应变测量计算误差的主要来源;为了提高DIC应变测量精度,基于局部加权回归方法对DIC位移场进行平滑去噪处理,提出了局部平滑去噪与最小二乘拟合的DIC应变测量算法;该方法与其他2种方法的比较以及复杂应变测量的模拟算例表明:局部平滑去噪方法计算编程简便、去噪效果明显、具有较好的适应性,提高了DIC应变测量精度。

Used computer to generate simulated speckle pattern,analyze digital image related DIC Newton-Rapson method to solve the noise introduced by displacement field and the main source of DIC strain measurement calculation error;in order to improve the local least squares fitting method of DIC strain measurement,increase DIC strain Measurement accuracy,based on the local weighted regression method to smooth and denoise the DIC displacement field,and propose a local smoothing and denoising DIC strain measurement algorithm;the comparison of this method with the other two methods and the simulation example of complex strain measurement show that:The smoothing denoising method has simple calculation and programming,obvious denoising effect,good adaptability,and improves the accuracy of DIC strain measurement.