摘要
对航空大型零部件的视觉测量时,采用传统的相机标定方法需要依靠高精度的标准参照物,大型的参照物加工难度大、精度难以保证,不能满足大视场相机标定要求。针对这些问题,提出了结合四角共线标志约束进行现场标定的方法;在空间测量视场范围内靠近主点的区域布置标定控制点,利用线性变换求解标定初值,在拍摄视场四角放置共线标志约束尺,利用交比不变性质以及直线拟合完成畸变系数求解,进行控制点的数量优化以及参数的整体优化得到现场标定最优解。相关标定实验结果表明在2.5 m×1.8 m的视场范围内现场重建误差小于0.07%,可以满足现场标定的高精度要求,对于航空大型零部件的视觉测量具有较好的稳健性与适用性。
For the vision measurement of aero large parts and components,traditional camera calibration methods relies on the high precision of standard targets which are difficult to be produced.The precision of these methods can not meet the need of large field of view for traditional camera calibration.Aiming at these problems,a sitecalibration method based on collinear constraints of mark points located at the four corners is put forward.Some calibration control points are arranged close to the principal point within space measurement field of view,and the calibration initial results can be solved using the linear transformation.The collinear constraint rulers are placed in the field of four corners,the distortion coefficients can be calibrated using cross-ratio invariability and linear fitting.The number of control points and the whole parameters of calibration can be optimized,and the optimal sitecalibration result can be obtained.The relative calibration experimental results show that in the field of view of 2.5m×1.8m,the reconstruction error of site is less than 0.07%,which meets the demand that the high precision of site-calibration,and has good robustness and adaptability for the vision measurement of aero large parts.
出处
《光学学报》
EI
CAS
CSCD
北大核心
2016年第7期178-187,共10页
Acta Optica Sinica
基金
国家973计划(2014CB046504)
国家自然科学基金(51227004
51375075)
国家自然科学基金创新研究群体项目(51321004)
辽宁省自然科学基金(2014028010)
关键词
机器视觉
视觉测量
相机标定
大视场
畸变校正
machine vision
vision measurement
camera calibration
large field of view
distortion correction
