Abstract: Aiming at the shortcomings of the conventional vision measurement method in the dynamic measurement of membrane structures, the target affects the local deformation of the film. The 3D dynamic measurement technology of membrane dot matrix projection is proposed. This technology uses a laser to project the target onto the membrane structure. Based on the OpenCV library（Open Source Computer Vision Library）, the 3D measurement algorithm is proposed to measure the 3D dynamic deformation of the membrane structure. In order to verify the 3D measurement accuracy, a standard ruler for accuracy inspection is designed. The 3D measurement accuracy of the membrane structure dot matrix projection measurement technology is tested in the principle verification experiment. The overall deformation and wave deformation of membrane structure are measured by 24 Hz frame rate photography and offline data processing. Accuracy verification experiments show that the technique can achieve the absolute accuracy of less than 0.30 mm and an accuracy of about 0.77 mm in the X, Y and Z directions, respectively, at the measurement distance of 1 m and the field of view of 1.3 m×0.8 m. At the same time, the dynamic measurement results can effectively replicate the dynamic deformation process of the membrane structure.

Key words: Membrane structure, 3D dynamic measurement, Photogrammetry, Dot matrix projection, Stereovision.

摘要： 针对常规视觉测量方法在薄膜类结构动态测量中靶标影响薄膜局部变形的弊端，提出了一种薄膜点阵投影式三维动态测量技术。此技术利用激光器将靶标投影到薄膜结构上，并基于OpenCV库（开源计算机视觉库）提出了一套三维测量算法进行薄膜结构三维动态变形测量。为了验证其三维测量精度，设计了精度检验的标准尺。在原理验证实验中检验了薄膜结构点阵投影式测量技术的三维测量精度，并以24 Hz帧率拍摄、离线处理数据的方式对薄膜结构的整体变形和波浪变形工况进行测量。精度验证实验结果证明了此技术在1 m的测量距离与1.3 m×0.8 m视场下，X、Y方向的精度小于0.30 mm，Z方向的精度约0.77 mm，同时动态测量结果能够有效复现薄膜结构动态变形过程。

关键词: 薄膜结构, 三维动态测量, 摄影测量, 点阵投影式, 立体视觉