基于数字图像相关的光学引伸计应变测量精度研究

朱飞鹏; 龚琰; 白鹏翔; 雷冬

doi:doi:10.3788/ope.20182605.1061

光学精密工程, 2018, 26 (5): 1061, 网络出版: 2018-08-14

基于数字图像相关的光学引伸计应变测量精度研究

Study on strain measurement accuracy of optical extensometers based on digital image correlation

论文大纲

朱飞鹏 ^*龚琰白鹏翔雷冬

作者单位

河海大学力学与材料学院, 江苏南京 211100

摘要

基于数字图像相关(DIC)方法的光学引伸计在应变测量领域有着广泛的应用。为了提高数字图像相关方法的测量精度, 本文采用二维DIC与三维DIC的光学引伸计、基于双45°反射镜成像的二维光学引伸计以及电测法, 对单轴拉伸试验中不锈钢试件的应变进行同时测量, 比较分析了各个光学引伸计在测量轴向与横向应变方面的优劣以及误差产生的原因。实验结果表明: 试件离面运动的存在大幅降低了普通二维光学引伸计的应变精度; 基于双45°反射镜成像的二维光学引伸计可以有效消除离面刚体位移对测量结果的影响, 其应变测量精度(尤其是横向应变精度)高于其他光学引伸计, 且测量结果与电测法的测量结果高度吻合; 三维DIC光学引伸计的横向应变精度明显不如轴向应变精度。

Abstract

Although optical extensometers based on Digital Image Correlation (DIC) method have widespread applications in strain measurement, there is a lack of systematic research on the strain measurement accuracy. For the uniaxial tensile test, testing equipment including the traditional 2D-DIC optical extensometer, three-dimensional digital image correlation (3D-DIC) optical extensometer, 2D-DIC optical extensometer equipped with dual-reflector imaging capability, and strain gauge were employed to measure the strain of stainless steel simultaneously. The results of axial and transverse strain measurement using different optical extensometers were compared, and the corresponding sources of measurement error were analyzed. The experimental results revealed that the traditional 2D-DIC optical extensometer yields low measurement accuracy because of the presence of out-of-plane motion. The 2D-DIC optical extensometer equipped with dual-reflector imaging capability can eliminate the effect of out-of-plane rigid body displacement and thus, ensure higher measurement accuracy, especially for transverse strain measurement, compared to other optical extensometers. Notably, the strain measurement results obtained using the 2D-DIC optical extensometer equipped with dual-reflector imaging capability were in good agreement with those obtained using a strain gauge. The measurement accuracy of transverse strain using 3D-DIC optical extensometer is apparently lower than that of axial strain.

参考文献

[1] 刘聪, 戴云彤, 戴美玲, 等. 二维多相机全场数字图像相关变形测量方法［J］. 光学学报, 2016, 36(12): 1212002.

LIU C, DAI Y T, DAI M L, et al.. Deformation measurement by two-dimensional multi-camera full-field digital image correlation ［J］. Acta Optica Sinica, 2016, 36(12): 1212002. (in Chinese)

[2] YONEYAMA S, KITAGAWA A, IWATA S, et al.. Bridge deflection measurement using digital image correlation ［J］. Experimental Techniques, 2007, 31(1): 34-40.

[3] 戴云彤, 陈振宁, 朱飞鹏, 等. 小尺寸低碳钢试件吕德斯效应的三维数字图像相关测量［J］. 力学学报, 2015, 47(1): 119-126.

DAI Y T, CHEN ZH N, ZHU F P, et al.. Measurement of Lüders band in small size low carbon steel specimen by 3D digital image correlation method ［J］. Chinese Journal of Theoretical and Applied Mechanics, 2015, 47(1): 119-126. (in Chinese)

[4] SHAO X X, DAI X J, CHEN ZH N, et al.. Real-time 3D digital image correlation method and its application in human pulse monitoring ［J］. Applied Optics, 2016, 55(4): 696-704.

[5] ZHU F P, BAI P X, ZHANG J B, et al.. Measurement of true stress-strain curves and evolution of plastic zone of low carbon steel under uniaxial tension using digital image correlation ［J］. Optics and Lasers in Engineering, 2015, 65: 81-88.

[6] 戴美玲, 徐向阳, 杨福俊, 等. 薄壁球壳受刚性平面压缩的连续变形测量［J］. 光学精密工程, 2016, 24(5): 993-1000.

DAI M L, XU X Y, YANG F J, et al.. Measurement of continuous deformation of thin-walled spheres compressed by a rigid plate ［J］. Opt. Precision Eng., 2016, 24(5): 993-1000. (in Chinese)

[7] TOURLONIAS M, BUENO M A, BIGU L, et al.. Contactless optical extensometer for textile materials ［J］. Experimental Mechanics, 2005, 45(5): 420-426.

[8] ZHANG D, AROLA D, CHARALAMBIDES P G, et al.. On the mechanical behavior of carbon-carbon optic grids determined using a bi-axial optical extensometer ［J］. Journal of Materials Science, 2004, 39(14): 4495-4505.

[9] KUMAR K, POOLEERY A, MADHUSOODANAN K, et al.. Optimisation of thickness of miniature tensile specimens for evaluation of mechanical properties ［J］. Materials Science and Engineering: A, 2016, 675: 32-43.

[10] DUBOS P A, FLEURIER G, HUG E. An experimental investigation of the size effects in forming processes of high-purity thin metallic sheets ［J］. Materials Science Forum, 2016, 879: 459-464.

[11] 王伟, 何小元. 光学引伸计在低维材料实时应变测量中的应用［J］. 光学学报, 2010, 30(6): 1662-1666.

WANG W, HE X Y. Application of optical extensometer on the real-strain measurement of low-dimensional materials ［J］. Acta Optica Sinica, 2010, 30(6): 1662-1666. (in Chinese)

[12] PAN B, TIAN L. Advanced video extensometer for non-contact, real-time, high-accuracy strain measurement ［J］. Optics Express, 2016, 24(17): 19082-19093.

[13] SUTTON M A, YAN J H, TIWARI V, et al.. The effect of out-of-plane motion on 2D and 3D digital image correlation measurements ［J］. Optics and Lasers in Engineering, 2008, 46(10): 746-757.

[14] BAI P X, ZHU F P, HE X Y. Optical extensometer and elimination of the effect of out-of-plane motions ［J］. Optics and Lasers in Engineering, 2015, 65: 28-37.

[15] ZHU F P, BAI P X, SHI H J, et al.. Enhancement of strain measurement accuracy using optical extensometer by application of dual-reflector imaging ［J］. Measurement Science and Technology, 2016, 27(6): 065007.

[16] 朱飞鹏, 王京荣, 雷冬, 等. 三维DIC在GFRP锚杆拉伸力学性能测试中的应用［J］. 实验力学, 2014, 29(3): 302-309.

ZHU F P, WANG J R, LEI D, et al.. Application of 3D-DIC in tensile mechanical properties test for glass fiber reinforced plastic bolt ［J］. Journal of Experimental Mechanics, 2014, 29(3): 302-309. (in Chinese)

[17] SHAO X X, EISA M M, CHEN ZH N, et al.. Self-calibration single-lens 3D video extensometer for high-accuracy and real-time strain measurement ［J］. Optics Express, 2016, 24(26): 30124-30138.

[18] 潘兵, 谢惠民, 李艳杰. 用于物体表面形貌和变形测量的三维数字图像相关方法［J］. 实验力学, 2007, 22(6): 556-567.

PAN B, XIE H M, LI Y J. Three-dimensional digital image correlation method for shape and deformation measurement of an object surface ［J］. Journal of Experimental Mechanics, 2007, 22(6): 556-567. (in Chinese)

朱飞鹏, 龚琰, 白鹏翔, 雷冬. 基于数字图像相关的光学引伸计应变测量精度研究[J]. 光学精密工程, 2018, 26(5): 1061. ZHU Fei-peng, GONG Yan, BAI Peng-xiang, LEI Dong. Study on strain measurement accuracy of optical extensometers based on digital image correlation[J]. Optics and Precision Engineering, 2018, 26(5): 1061.

基于数字图像相关的光学引伸计应变测量精度研究

关于本站 Cookie 的使用提示

全站搜索

基于数字图像相关的光学引伸计应变测量精度研究

相关论文

相关资讯

关于本站 Cookie 的使用提示

全站搜索