连续视场的多相机数字图像相关测量方法

Multi-camera Digital Image Correlation Method with Continuous View Field

为拓展三维数字图像相关方法的应用范围并提高测量精度,将数字图像相关方法和多相机同步采集系统相结合,形成连续视场的多相机三维数字图像相关测量方法,在满足大长细比、大曲率和复杂全表面连续变形测量需求的同时,提高应变测量精度。多个相机同步拍摄物体表面的不同区域,相邻局部区域之间满足视场重叠范围要求,通过多相机标定将数据点映射至同一全局坐标系下,实现连续视场的多相机数字图像相关测量。利用双相机系统和多相机系统同时观测板的平移实验和梁的三点弯曲实验,结果表明,连续视场的多相机数字图像相关测量方法充分利用相机空间分辨率,一定程度上提高了三维变形测量精度。

To promote the application and the measurement accuracy of the three-dimensional digital image correlation method,the digital image correlation method and the multi-camera synchronous acquisition system are combined to form a multi-camera three-dimensional digital image correlation method with continuous view field.The full-surface continuous deformation measurement requirements of objects with large slenderness,large curvature and complex surface are fulfilled,meanwhile the strain measurement accuracy is improved.Different local areas of the measured surface are simultaneously captured by multiple cameras,in which a certain view field overlap between adjacent areas is satisfied.Through multi-camera calibration,multiple cameras are unified into a global coordinate system to achieve multi-camera digital image correlation measurement with continuous view field.The stereo-camera system and multi-camera system are utilized to measure the translation experiment of plate and bending experiment of beam.Experimental results indicate that the multi-camera digital image correlation method with continuous view field makes full use of cameras'spatial resolution and improves the deformation measurement accuracy to some extent.