Fast, Robust and Accurate Digital Image Correlation Calculation Without Redundant Computations

作     者：Pan, B. Li, K. Tong, W. 

作者机构：Beijing Univ Aeronaut & Astronaut Inst Solid Mech Beijing 100191 Peoples R China Shanghai Univ Dept Mech Engn Shanghai 200444 Peoples R China So Methodist Univ Dept Mech Engn Dallas TX 75275 USA 

出 版 物：《EXPERIMENTAL MECHANICS》 (实验力学)

年 卷 期：2013年第53卷第7期

页      面：1277-1289页

核心收录：

学科分类：08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0801[工学-力学（可授工学、理学学位）] 080102[工学-固体力学] 

基　　金：National Natural Science Foundation of China [11272032, 11002012, 91216301] Program for New Century Excellent Talents in University China Aerospace Science and Technology Innovation Fund Project [CASC201101] Aeronautical Science Foundation of China [2011ZD51043] Specialized Research Fund for the Doctoral Program of Higher Education 

主　　题：Digital image correlation Image matching Sub-pixel displacement Inverse compositional image alignment algorithm Newton-Raphson algorithm 

摘      要：High-efficiency and high-accuracy deformation analysis using digital image correlation (DIC) has become increasingly important in recent years, considering the ongoing trend of using higher resolution digital cameras and common requirement of processing a large sequence of images recorded in a dynamic testing. In this work, to eliminate the redundant computations involved in conventional DIC method using forward additive matching strategy and classic Newton-Raphson (FA-NR) algorithm without sacrificing its sub-pixel registration accuracy, we proposed an equivalent but more efficient DIC method by combining inverse compositional matching strategy and Gauss-Newton (IC-GN) algorithm for fast, robust and accurate full-field displacement measurement. To this purpose, first, an efficient IC-GN algorithm, without the need of re-evaluating and inverting Hessian matrix in each iteration, is introduced to optimize the robust zero-mean normalized sum of squared difference (ZNSSD) criterion to determine the desired deformation parameters of each interrogated subset. Then, an improved reliability-guided displacement tracking strategy is employed to achieve further speed advantage by automatically providing accurate and complete initial guess of deformation for the IC-GN algorithm implemented on each calculation point. Finally, an easy-to-implement interpolation coefficient look-up table approach is employed to avoid the repeated calculation of bicubic interpolation at sub-pixel locations. With the above improvements, redundant calculations involved in various procedures (i.e. initial guess of deformation, sub-pixel displacement registration and sub-pixel intensity interpolation) of conventional DIC method are entirely eliminated. The registration accuracy and computational efficiency of the proposed DIC method are carefully tested using numerical experiments and real experimental images. Experimental results verify that the proposed DIC method using IC-GN algorithm and the exist