摘要
为解决现有的多目视觉线结构光测量系统在大视场测量时,相机之间无公共视场,导致标定工具要求高、全局标定过程复杂等问题,本文提出了一种基于辅助相机的多目视觉线结构光测量系统全局标定方法.首先,将辅助相机作为中介,它与线结构光传感器的相机有1/2左右的视场重叠,构成了双目子系统,通过拍摄标定板不同姿态的图像来建立辅助相机和相邻两个线结构光传感器的空间几何关系.然后基于此通过坐标转换求解出相邻两个无公共视场线结构光传感器的位置关系,最后再逐步换算求解出局部坐标系向全局坐标系统一的变换矩阵,完成全局标定过程.此方法对标定工具要求低,不需要借助高精度测量设备及复杂靶标,只需简易的棋盘格靶标即可完成多目视觉线结构光测量系统的全局标定,标定过程简单,并且可达到较高的标定精度.测量试验表明,该方法的全局标定误差是0.067 mm,有效提高了测量精度,为后续大构件的机器人“测量-加工”一体化作业提供精度保障.
To solve the problem of the absence of a common field of view between the cameras in the existing multi-vision line structured light measurement system,which leads to high requirements for calibration tools and complicated global-calibration process,a globalcalibration method for the multi-vision line structured light measurement system based on an auxiliary camera is introduced to achieve a large-field-of-view measurement.First,an auxiliary camera is used as an intermediary to acquire an approximately one-half overlapped field of view with the line structured light sensor,which can constitute a binocular subsystem.Then,the spatial geometric relationship between the auxiliary camera and two adjacent line structured light sensors is established based on the different pose images of the calibration plate.Second,the position relationship between the two adjacent line structured light sensors without a common field of view is solved using coordinate transformation.Finally,the transformation matrix from a local to a global coordinate system is solved one at a time to complete the global calibration process.The requirement in terms of calibration tools of the proposed calibration method is low.Further,it does require the use of high-precision measuring equipment and complex targets but only requires a simple chessboard target to complete the global calibration of a multi-vision line structured light measurement system.Meanwhile,the calibration process can achieve high calibration accuracy.Meanwhile,the measurement experiment demonstrates that the global calibration error of this method is 0.067 mm,which effectively improves the measurement accuracy and can guarantee the required accuracy for the integration of“measurement and machining”of large components using robots.
作者
葛庆如
严思杰
陈巍
吴龙
徐小虎
GE QingRu;YAN SiJie;CHEN Wei;WU Long;XU XiaoHu(Wuxi CRRC Times Intelligent Equipment Co.,Ltd.,Wuxi 214000,China;State Key Laboratory of Digital Manufacturing Equipment and Technology,Huazhong University of Science and Technology,Wuhan 430074,China)
出处
《中国科学：技术科学》
EI
CSCD
北大核心
2022年第8期1274-1284,共11页
Scientia Sinica(Technologica)
基金
国家重点研发计划(编号:2019YFA0706703)
国家自然科学基金(批准号:52075204)
国家青年科学基金(编号:52105514)资助项目。
关键词
辅助相机
大视场
全局标定
多目视觉线结构光测量系统
auxiliary camera
large field of view
global calibration
multi-vision line structured light measurement
