中文摘要：

针对工业视觉测量中的摄像机标定精度及效率低的问题,提出一种高精度CCD相机分区域标定方法.该方法首先利用三坐标测量机（CMM）带动圆形发光二极管（LED）光靶标按梯形台状做精确空间移动,结合最小二乘椭圆拟合算法求解光靶标的像面位置,并与CMM三维坐标形成精确的空间标定点集.同时,将像平面按圆环形对称结构分割成N个区域,并结合改进的Tsai算法分别对每个子区域进行相机参数的标定.标定实验结果表明：经过分区域标定,相机采集点的总误差比单区域标定法降低了17％（N=8）,单点平均误差降低了20％左右.算法可实现自动精确标定点采集,操作过程简单,基本满足中等精度的工业测量要求.所提出的相机标定法可应用于工业视觉测量,特别是大工件测量领域.

英文摘要：

A reliable sub-regional calibration method for CCD cameras was proposed to improve the accuracy and efficiency of industrial vision measurement. With the proposed method, a round light target was moved with the Coordinate Measuring Machine （CMM） according to a trapezoidal shape. The images of light target were pro- cessed with least square ellipse fitting algorithm to obtain the center positions. By 3D coordinates of CMM, a set of accurate calibration data were obtained. Furthermore, the image plane was separated into several sections ac- cording to the circle symmetrical structure and camera parameters in different regions were calculated with the sub-regional theory and improved Tsai method. Comparing with the sub-regional calibration method to single cal- ibration one, the actual calibration experiments show that the total error is decreased by 17% when the image is separated 8 regions and the average error of single point is decreased about 20% . Experiments demonstrate that the data collection process is automatic and simple, and the camera calibration accuracy meets the medium preci- sion of industrial measurement. It indicates that the method proposed is suitable for the industrial vision measure- ment, especially for the larger work piece measurement.