基于双目立体视觉的线结构光标定方法  

Line structured light calibration method based on binocular stereo vision

作　　者：严兴旭 杜虎兵[1] 王辉[1] 唐博[1] 张高鹏[2] 贾晋葛 YAN Xingxu;DU Hubing;WANG Hui;TANG Bo;ZHANG Gaopeng;JIA Jinge(School of Mechanical and Electrical Engineering,Xi'an University of Technology,Xi'an 710021,China;Xi'an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi'an 710119,China;Xi'an Future Intelligent Manufacturing Digital Technology Co.,LTD.,Xi'an 710000,China)

机构地区：[1]西安工业大学机电工程学院,陕西西安710021 [2]中国科学院西安光学精密机械研究所,陕西西安710119 [3]西安未来智造数字科技有限公司,陕西西安710000

出　　处：《红外与激光工程》2025年第1期209-220,共12页Infrared and Laser Engineering

基　　金：国家自然科学基金项目(51975448);国家重点研发计划项目(2019YFB2203002);中国科学院青年创新促进会会员项目(2022410);陕西省“科学家+工程师”队伍建设项目(2023KXJ-280)。

摘　　要：结构光三维轮廓测量方法目前是三维形状测量的热点,而其中的线结构光技术因其成本低、效率高、精度高成为复杂物体三维轮廓测量方法的典型代表。然而,现有的线结构光法在应用中存在着标定困难、标定精度低等问题,对此,结合双目视觉系统与具有固定特征点的靶标,建立了一种高效、可靠的激光平面方程标定方法。该方法仅需要一个平面靶标和一个额外的相机,只记录两处位置的标定图像便可完成测量系统标定工作。工作时,首先结合左、右标定图像提取的光刀中心和角点获得特征点的像素坐标;然后,通过匹配左、右图像上对应的特征点,确定相机坐标系下特征点的三维坐标;进而,基于多组不同位置的三维特征点坐标,利用最小二乘法拟合激光平面,获得激光平面方程的参数。以标准块为样品的长度测量实验表明,该方法灵活实用、靶标设计简单、具有特征点丰富的优点,相比于典型标定方法,其可高精度地完成系统标定工作,量块宽度测量实验的结果更接近于参考值。另外,对比商用线激光传感器的测量结果,文中方法的测量精度提高了约10μm。Objective High accuracy and precision 3D measurement have been extensively employed for industrial inspection,object three-dimensional reconstruction and reverse engineering.Many methods can be used to achieve the objective.Among then,line-structured light technique is regarded as a representative of the techniques of this kind owing to their advantages of high accuracy,high robustness,rapid speed,non-contact,and low cost.However,the existing line-structured light method suffers from calibration difficulties and low calibration accuracy in applications.In this regard,this paper establishes an efficient and reliable calibration method for laser plane equation by combining a binocular vision system with a target with fixed feature points.Methods The measurement system consists of a camera and a structured light projector.During the task of measurement,the light projector projects the laser stripe on the object to be measured,and the image is collected by the detector.the three-dimensional coordinates of the object are obtained based on the principle of laser triangulation if the pixel coordinate position is laser stripe centers obtained through image processing.Specifically,the calibration process of the line structured light vision system includes camera calibration and laser planes calibration.For the camera calibration,which mainly involves calculating the internal and external parameter matrix of the imaging system and the aberration coefficient,the process is considered more mature and can be well done by Zhang’s method because of its high calibration accuracy,flexibility,and low cost.The calibration process of line-structured light 3D measurement system is as follows:1)The line laser emits linestructured light stripes,which project the light plane onto the target’s surface to produce the left and right calibration images;2)The camera acquires the calibration images and extracts the feature points of the structured light contour from the light knife of the left and right calibration images;3)Calculation of

关 键 词：线结构光 双目视觉 平面靶标 相机标定 激光平面标定 

分 类 号：TH741[机械工程—光学工程]