结构光系统标定方法研究

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题名	结构光系统标定方法研究
作者	高伟
学位类别	工学博士
答辩日期	2008-05-23
授予单位	中国科学院研究生院
授予地点	中国科学院自动化研究所
导师	胡占义
关键词	三位轮廓测量结构光系统便携式结构光系统相机标定投影仪标定相位移动算法模块补偿算法 3D shape measurement structured light system portable structured light system camera calibration projector calibration phase shift algorithm compensating modules algorithm
其他题名	A Study for Calibrating Structured Light System
学位专业	模式识别与智能系统
中文摘要	基于结构光系统的物体三维轮廓测量技术,由于具有测量速度快、非接触式等好的特性，因而在科学和商业领域得到了广泛的应用。一个基本的结构光系统包括一个相机和一个光栅条纹投射器。透射器将光栅条纹透射到物体表面，相机获取到受物体高度调制后的条纹图像。通过分析条纹图像，获得物体轮廓的三维信息。与立体视觉系统相比，结构光系统简化了对应点匹配问题。但是，在对物体进行三维轮廓测量之前，需要对结构光系统进行精确地标定。尽管国内外的许多学者提出了针对特定结构光系统的各种标定方法，但是在实际应用中，仍存在一些问题有待解决。因此，本文主要针对结构光系统标定的便捷性、普适性和准确性问题进行了研究和探索，所完成的主要工作有： 1）针对在结构光系统标定方法中，用于标定的设备比较昂贵，或者是标定过程复杂、费时的缺点，提出了一种基于模型平板诱导的单应矩阵的简易标定结构光系统的技术。整个标定过程只需要两个模板，一个模板固定在模型平板上，另外一个模板由投影仪透射到模型平板上。研究了两种不同的标定方法，一种称为黑白棋格法，另一种称为红蓝棋格法。在模型平板的每一个位置只需要拍摄一到两幅照片，就可以完成整个标定过程，该技术简单、易用。 2）针对在便携式结构光系统中，对于系统标定方法易用性的要求，提出了一种基于交比和极几何的便携式结构光系统标定技术。设计了特殊的标定板和参考板，使得该技术只需要一个模型平板就可以完成整个系统的标定，并能取得比较高的标定精度。 3）针对在彩色相位移动技术中，由于投影仪和相机之间的非线性响应、各个颜色通道之间的耦合性以及各个颜色通道之间的灰度值响应不平衡等，使得直接利用该技术进行三维测量会产生较大的误差的问题，提出了一系列模块补偿算法，通过利用多项式拟合、耦合性评价矩阵和通道平衡等方法来减少误差值。
英文摘要	Measurement of the 3D shape of objects based on the structured light techniques has found numerous applications in scientific and commercial fields due to their fast speed and non-contact nature. Typically, a sturctured light system consists of a camera and a projector in which the projector projects specially designed patterns on the objects, while the camera captures images of the paterns. By analyzing the captured images of the patterns, the 3D shape of objects are derived and the difficult corresponding problem in a classic stereo vision system is alleviated. However, the structured light system must be fully calibrated prior its usage. Although numerous approaches to calibrate a structured light sytem are reported in the literature, many difficult problems persist in the real progress of applications. This thesis is focused on the flexible, general, and accurate calibration techniques. The main work can be summarized as follows: 1)In the current available calibration methods for the structured light system, either the expensive equipments are used or the calibration procedures seem completed and time-consuming. We propose a flexible technique to easily calibrate a sturctured light system based on the homography induced by a model plane. The total procedure only requires two patterns, one is attached to a model plane, the other is projected on the model plane by a LCD projector. In order for the projector to see the calibration board like a camera, two approaches are proposed, one is called the black-and-white checkerboard method, the other is the red-and-blue checkerboard method. At each position, only one or two images need to be caputured, and the calibration procedure is completely automatic. The proposed technique is easy to use and efficient. 2)For a portable structured light system, the calibration method must be easy to use and flexible. A flexible calibration method is proposed to meet the requirements of the portable structured light system through a surface plane based on cross ratio and epipolar geometry. The special calibration board and reference board are designed, and the calibration procedure is completed and rather accurate with one model plane. 3)There would be more errors if the color phase-shifting technique were dirctly used for 3D shape measurement due to the nonlinear response curve, coupling and imbalance of projector and camera. Several compensating modules, including polynomial fitness, coupling evaluated matrix, balance of different channels and so on, are proposed to correct these errors.
语种	中文
其他标识符	200518014628047
内容类型	学位论文
源URL	[http://ir.ia.ac.cn/handle/173211/6065]
专题	毕业生_博士学位论文
推荐引用方式 GB/T 7714	高伟. 结构光系统标定方法研究[D]. 中国科学院自动化研究所. 中国科学院研究生院. 2008.