基于三维数字图像相关法的非接触式动态位移测量方法研究

Research on Non-contact Dynamic Displacement Measurement Method Based on 3D Digital Image Correlation Method

摘要:

在动力学实验中,准确测量实验模型的动态位移响应是保证实验品质的关键环节,传统获取位移响应的方法都存在一定缺陷,比如无法全场测量,动态测量效果较差等。针对这些缺陷,提出了一种基于三维数字图像相关法 (3D-Digital Image Correlation)的非接触式光学动态位移测量方法,并搭建了基于三维数字图像相关法的非接触式光学测量平台,通过地面实验,将测量结果与真实位移进行对比分析,对其使用范围和精度进行了验证。实验结果表明,在像面内平移或垂直运动时,测量精度可靠；在绕像面横轴旋转运动时,角度应尽量小于20°。实验结果为基于三维数字图像相关法的测量技术提供了有效的参考。

Abstract:

In the dynamic experiment, accurate measurement of the dynamic displacement response of the experimental model is the key to ensure the quality of the experiment. The traditional method of obtaining the displacement response has some defects, such as unable to measure the whole field, poor dynamic measurement effect and so on. In view of these defects, a non-contact optical dynamic displacement measurement method based on three-dimensional digital image correlation is proposed, and a non-contact optical measurement platform based on three-dimensional digital image correlation is built. Through ground experiments, the measured results are compared with the real displacement, and its application range and accuracy are verified. The experimental results show that the measurement accuracy is reliable when the image plane is in translational or vertical motion; When rotating around the horizontal axis of the image plane, the angle should be less than 20 as far as possible .The experimental results provide an effective reference for the measurement technology based on 3D digital image correlation method.