Sub-pixel extraction of laser stripeand itsapplication in laser plane calibration  

亚像素级激光光条提取及其激光平面标定应用(英文)

作　　者：陈平[1] 张志胜[1] 戴敏[1] 陈恺[1] 

机构地区：[1]东南大学机械工程学院,南京211189

出　　处：《Journal of Southeast University(English Edition)》2015年第1期107-112,共6页东南大学学报（英文版）

基　　金：The National Natural Science Foundation of China(No.50805023);the Science and Technology Support Program of Jiangsu Province(No.BE2008081);the Research and Innovation Project for College Graduates of Jiangsu Province(No.CXZZ13_0086);Scientific Research Foundation of Graduate School of Southeast University(No.YBJJ1401)

摘　　要：For calibrating the laser plane to implement 3D shape measurement, an algorithm for extracting the laser stripe with sub-pixel accuracy is proposed. The proposed algorithm mainly consists of two stages： two-side edge detection and center line extraction. First, the two-side edge of laser stripe is detected using the principal component angle-based progressive probabilistic Hough transform and its width is calculated through the distance between these two edges. Secondly, the center line of laser strip is extracted with 2D Taylor expansion at a sub-pixel level and the laser plane is calibrated with the 3D reconstructed coordinates from the extracted 2D sub-pixel ones. Experimental results demonstrate that the proposed method can not only extract the laser stripe at a high speed, nearly average 78 ms/frame, but also calibrate the coplanar laser stripes at a low error, limited to 0.3 mm. The proposed algorithm can satisfy the system requirement of two-side edge detection and center line extraction, and rapid speed, high precision, as well as strong anti-jamming.为了标定激光平面以实现三维形貌测量,提出一种亚像素级精度激光光条提取算法.该算法包括两侧边检测和中心线提取2个部分.首先,利用基于主成分角的渐进概率霍夫变换检测2条侧边并依赖该两侧边的距离获取光条宽度;然后,应用二维泰勒展式提取具有亚像素级精度的光条中心线并依据重建的三维坐标标定激光平面.实验结果表明,所提算法光条中心提取速度较快,平均约为78 ms/帧,光条平面共面误差较低,限制在0.3 mm以内.因而所提算法能够满足提取光条的两侧边和中心线的需要,且快速可靠、精度高和抗干扰能力强.

关 键 词：sub-pixel extraction center line extraction laser plane calibration progressive probabilistic Hough transform （PPHT） principal component （PC） angle 2D Taylor expan- sion 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术] TN911.73[自动化与计算机技术—计算机科学与技术]