基于光纤传像束成像的双相机三维数字图像相关方法  

3D digital image correlation method based on fiber optic image bundle imaging

作　　者：张燕燕 于玲[1] 张中亚 郑会龙[2] ZHANG Yanyan;YU Ling;ZHANG Zhongya;ZHENG Huilong(Liaoning University of Technology,Jinzhou 12100l,Liaoning,China;Institute of Engineering Thermophysics,Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]辽宁工业大学,辽宁锦州121001 [2]中国科学院工程热物理研究所,北京100190

出　　处：《实验力学》2024年第3期367-377,共11页Journal of Experimental Mechanics

基　　金：国家科技重大专项(J2019-V-006-0100);中科院青促会会员项目(2022142)。

摘　　要：数字图像相关方法的变形测量,通常会使用常规双相机进行图像采集,然而由于系统光学结构的限制,应用也受到了一定的制约。本文将光纤传像束和三维数字图像相关方法(Three-Dimensional Digital Image Correction,3D-DIC)相结合,提出一种基于光纤传像束成像的双相机三维数字图像相关方法。旨在充分利用传像束的灵活性,进一步拓宽3D-DIC方法的应用范围。由于系统中的传像束将相机和测量环境隔离,在恶劣环境下可以有效避免相机的损坏。首先,分析了不同滤波方法预处理散斑图像对测量结果的影响;然后,通过平移试验研究了散斑尺寸和密度对测量结果的影响;最后,开展了圆柱体形貌测量试验和304不锈钢单轴拉伸试验。结果表明:散斑直径为21~23pixel且密度为55%时使用该方法可得到最佳的测量结果,同时该方法不仅能够获取圆柱体的三维形貌,还能够准确测量单轴拉伸试验的全场变形,以电子引伸计为基准,相对误差始终保持在小于0.25%的范围内。Deformation measurement using Digital Image Correlation(DIC)methods often employs conventional dual-camera systems for image acquisition.However,the application is constrained to some extent due to the limitations of the optical structure of the system.This paper proposed a dual-camera three-dimensional DIC method based on fiber optic imaging bundles and 3D-DIC,aiming to fully utilize the flexibility of the imaging bundle and further expand the application range of 3D-DIC methods.By isolating the cameras from the measurement environment using the imaging bundle in the system,damage to the cameras can be effectively avoided in harsh environments.Firstly,the influence of different filtering methods on the measurement results of speckle images was analyzed.Then,the effects of speckle size and density on the measurement results were studied through translation experiments.Finally,experiments on the measurement of cylindrical surface morphology and uniaxial tensile tests of 304 stainless steel were conducted.The results show that the best measurement results can be obtained.When the speckle diameter is 21~23pixel and the density is 55%using this method.Furthermore,this method can not only obtain the three-dimensional morphology of the cylinder but also accurately measure the overall deformation of the uniaxial tensile test,with the relative error compared to the electronic extensometer always maintained within the range of less than 0.25%.

关 键 词：光纤传像束 数字图像相关方法 变形测量 双相机 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]