大尺度三维几何尺寸立体视觉测量系统实现

基于立体视觉的大尺度三维几何尺寸测量技术是对外形不规则的大型物体进行几何量测量的有效方法。与传统的视觉测量技术不同,大尺度视觉测量的精度随测量距离的增加而迅速下降,同时大尺度空间下照明条件难以控制,也使得测量变得不稳定。因此如何在大测量尺度的前提下提高测量精度成为这一领域的研究难点。从立体视觉测量系统的原理出发,分析了影响系统精度的各种因素,将相位一致性变换与极线约束条件引入结构光光条中心提取之中,显著提高了图像分析的精度。研制了测量系统的样机并给出了实验结果,现场测试表明该系统可以有效地保证大尺度条件下的测量精度。

Large-Scale Three-Dimensional Stereo Vision Geometric Measurement System

Large-scale three-dimensional vision measurement based on stereo vision is an effective and flexible method for precise space coordinates measurement when the object′s shape is irregular and the size is relatively large. Different from traditional methods, the accuracy of large-scale vision measurement degrades with distance rapidly. Meanwhile, it is hard to control the illumination under large-scale condition, which also makes the measurement quite unsteadily. Thus how to maintain the accuracy under large-scale situation becomes the key technique problem to be solved. The principle of the vision measurement system is introduced. The factors which affect the measuring accuracy are analyzed. Structured light extraction method with phase congruency and epipolar constraint is proposed which can increase the image analysis accuracy obviously. A prototype is developed and the experimental results show that the proposed method is of high accuracy and large measuring range.