Abstract
In this paper, we report the following important progress recently made in the basic theory and practical implementation of digital image correlation (DIC) for deformation measurement. First, we answer a basic but confusing question to the users of DIC: what is a good speckle pattern for DIC? We present a simple, easy-to-compute yet effective global parameter, called mean intensity gradient, for quality assessment of the entire speckle pattern. Second, we provide an overview of various correlation criteria used in DIC for evaluating the similarity of the reference and deformed subsets, and demonstrate the equivalence of three robust and most widely used correlation criteria, i.e., a zero-mean normalized cross-correlation (ZNCC) criterion, a zero-mean normalized sum of squared difference (ZNSSD) criterion and a parametric zero-mean normalized sum of squared difference (PSSDab) criterion with two additional unknown parameters, which elegantly unifies these correlation criteria for subset-based pattern matching. Third, we describe an iterative least squares (ILS) algorithm for accurate subpixel motion detection, which is proved to be equivalent to the existing Newton–Raphson algorithm, but the principle and implementation of ILS algorithm is more straightforward and easier. Finally, to overcome the two limitations of existing subset-based DIC technique, we introduce a robust and generally applicable reliability-guided DIC technique, in which the calculation path is guided by the ZNCC coefficients of computed points, to determine the genuine full-field deformation of an object with complex shape.
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Pan B, Qian KM, Xie HM, Asundi A (2009) Two-dimensional digital image correlation for in-plane displacement and strain measurement: a review. Meas Sci Technol 20:062001
Sutton MA, Orteu JJ, Schreier HW (2009) Image correlation for shape, motion and deformation measurements. Springer
Lecompte D, Smits A, Bossuyt S et al (2006) Quality assessment of speckle patterns for digital image correlation. Opt Lasers Eng 44(11):1132–1145
Haddadi H, Belhabib S (2008) Use of rigid-body motion for the investigation and estimation of the measurement errors related to digital image correlation technique. Opt Lasers Eng 46:185–96
Sun YF, Pang HJ (2007) Study of optimal subset size in digital image correlation of speckle pattern images. Opt Lasers Eng 45:967–974
Giachetti A (2000) Matching techniques to compute image motion. Image Vis Comput 18:247–260
Tong W (2005) An evaluation of digital image correlation criteria for strain mapping applications. Strain 41(4):167–175
Pan B, Wang ZY, Xie HM (2009) Generalized spatial-gradient based digital image correlation for displacement and shape measurement with sub-pixel accuracy. J Strain Anal Eng Des 44:659–669
Pan B, Xie HM, Xu BQ, Dai FL (2006) Performance of sub-pixel registration algorithms in digital image correlation. Meas Sci Technol 17(6):1615–1621
Jin HQ, Bruck HA (2005) Theoretical development for pointwise digital image correlation. Opt Eng 44:1–14
Cheng P, Sutton MA, Schreier HW, McNeill SR (2002) Full-field speckle pattern image correlation with B-spline deformation function. Exp Mech 42:344–352
Sun Y, Pang JH, Wong CK, Su F (2005) Finite element formulation for a digital image correlation method. Appl Opt 44:7357–7363
Besnard G, Hild F, Roux S (2006) ‘Finite-element’ displacement fields analysis from digital images: application to Portevin-le chaterlier bands. Exp Mech 46:789–803
Pan B, Xie HM, Wang ZY, Qian KM, Wang ZY (2008) Study on subset size selection in digital image correlation for speckle patterns. Opt Exp 16(10):7037–7048
Wang YQ, Sutton MA, Bruch HA, Schreier HW (2009) Quantitative error assessment in pattern matching: effects of intensity pattern noise, interpolation, strain and image contrast on motion measurement. Strain 45:160–178
Pan B, Lu ZX, Xie HM (2010) Mean intensity gradient: an effective global parameter for quality assessment of the speckle patterns used in digital image correlation. Opt Lasers Eng 48(4):469–477
Pan B, Xie HM, Wang ZY (2010) Equivalence of digital image correlation criteria for pattern matching. Appl Opt 49:5501–5509
Pan B, Xie HM, Guo ZQ, Hua T (2007) Full-field strain measurement using a two-dimensional Savitzky-Golay digital differentiator in digital image correlation. Opt Eng 46(3):033601
Bruck HA, McNeil SR, Sutton MA, Peters WH (1989) Digital image correlation using newton-raphson method of partial differential correction. Exp Mech 29(3):261–267
Vendroux G, Knauss WG (1998) Submicron deformation field measurements: Part 2. Improved digital image correlation. Exp Mech 38(2):86–92
Lu H, Cary PD (2000) Deformation measurement by digital image correlation: implementation of a second-order displacement gradient. Exp Mech 40(4):393–400
Pan B, Asundi A, Xie HM, Gao JX (2009) Digital image correlation using iterative least squares and pointwise least squares for displacement field and strain field measurements. Opt Lasers Eng 47(7–8):865–874
Pan B (2009) Reliability-guided digital image correlation for image deformation measurement. Appl Opt 48(8):1535–1542
Pan B, Wang ZY, Lu ZX (2010) Genuine full-field deformation measurement of an object with complex shape using reliability-guided digital image correlation. Opt Express 18(2):1011–1023
Acknowledgements
This work is supported by “the National Natural Science Foundation of China (under grant 11002012)” and “the Science Fund of State Key Laboratory of Automotive Safety and Energy” (under grant KF10041). I am grateful to Prof. Dongsheng Zhang of Shanghai University, China for kindly allowing the use of their experimental images and to Prof. Zhaoyang Wang of The Catholic University of America for helpful discussions.
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This paper is based on and modified from an original paper presented as a 40-minute invited talk at 2010 SEM Annual Conference.
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Pan, B. Recent Progress in Digital Image Correlation. Exp Mech 51, 1223–1235 (2011). https://doi.org/10.1007/s11340-010-9418-3
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DOI: https://doi.org/10.1007/s11340-010-9418-3