多相机3D-DIC及其在高温变形测量中的应用  

On the Multiple Camera 3D-DIC System and its Application in Deformation Measurement at High Temperature

作　　者：陈凡秀[1] 陈旭[2] 谢辛[2] 徐楠[2] 冯秀[3] 杨连祥[2] 

机构地区：[1]青岛理工大学理学院,青岛266033 [2]奥克兰大学机械工程系,密歇根州48309 [3]南京化工职业技术学院,南京210048

出　　处：《实验力学》2015年第2期157-164,共8页Journal of Experimental Mechanics

基　　金：国家自然科学基金资助(No.11472145;51008166)

摘　　要：将基于双目视觉的三维数字图像相关方法 （Three-dimension digital image correlation,3D-DIC）与多相机同步采集系统相结合,形成基于多相机的3D-DIC系统。依据三维空间误差（Three-dimensional residual,3Dresidual）最小原则,确定各点对应的最佳双目视觉系统,获得物体全场三维变形。以四相机3D-DIC系统为例,与测量精度达10-20nm的电子散斑干涉测量系统同时对平板的离面位移进行测量,并对测量得到的离面位移最大值进行了对比分析。结果显示,荷载较小时,四相机3D-DIC与电子散斑干涉测量系统误差稍大,最大达到2.7%;荷载增大,物体变形增大时,两种测量系统结果基本相同。文中讨论了四相机测量系统的不稳定对实验结果的影响。利用该四相机3D-DIC系统对镍合金不锈钢材料在高温场中的变形进行测量,获得了物体的三维变形场,并分析了材料的膨胀系数,得到了试件的热应变-温度曲线和膨胀系数随温度变化的关系式。In order to obtain 3Ddeformation of object,combining 3D-DIC system（Three-Dimensional Digital Image Correlation）based on binocular vision principle with multiple camera synchronous acquisition system to form a multiple camera 3D-DIC system.Based on minimum three-dimensional（3D）residual principle,a system,in which each point is corresponding to the best binocular vision is determined.Thus,3Dcontour and 3Ddeformation of object can be obtained.Taking a four-camera3D-DIC system as the example,measurement of flat plate out plane displacement was carried out by synchronously using electronic speckle pattern interferometry system with accuracy of 10-20nm and above proposed system,and the obtained maximum out plane displacement was compared.Results show that when load is small,the maximum error from proposed 3D-DIC system is 2.7%,larger than that from electronic speckle system.With the load increasing（the deformation becomes larger）,the measurement results from both measuring systems are basically agree well.The infuluence of instability of four-camera 3D-DIC system on experimental results is analyzed in this paper.Using above proposed system,3D deformation of a specimen made of nickel alloy stainless steel was measured at high temperature,3Ddeformation of specimen was obtained,strain-temperature curve and relation between expansion coefficient and temperature were analyzed.

关 键 词：多相机 三维数字图像相关 变形 高温 

分 类 号：O348[理学—固体力学]