基于体视显微镜的测量系统标定研究

微观三维变形测量系统在工程上有广泛的应用。本文构建了体视显微镜双相机微观图像采集与测量系统,可以实现对微小物体形貌、位移、变形的全场测量。微观三维变形的测量精度与成像系统的畸变模型存在密切的关系。本文采用了考虑多种不确定情况的畸变模型,能很好地表达体视显微镜测量系统的成像误差,并设计了点阵式标定模板和精密的平动平台,实现了基于Tsai标定的自动标定算法。实验表明,体视显微镜测量系统可以在各种放大倍数下稳定工作,标定的精度得到很大的提高,并给出了在不同放大倍数下对规则圆柱体的形貌和直径的测量结果。

Study of Measuring System Calibration Based on Stereomicroscopy

Microscopic 3D deformation measurement system is widely applied in engineering.In this paper,a microscopic image acquisition and measurement system was constructed first,based on stereomicroscope dual-camera imaging system.By using digital image correlation method,the whole field measurement of micro object's morphology,displacement and deformation can be realized.The measurement accuracy of micro 3D deformation is closely related to distortion model of imaging system.In this study,a distortion model is adopted,which takes various uncertainties into account and can well express imaging errors of stereomicroscope measuring system.Dot matrix calibration template and a precise translational platform were designed.An automatic calibration algorithm was realized based on Tsai calibration.Experimental results show that the stereomicroscope measuring system can work stably under condition of various amplification times,the calibration accuracy is greatly improved.The measured results including morphology and diameter of a regular cylinder under different magnification are also given in this paper.