一种基于双目相机与单点激光测距仪的标定方法  

Calibration method based on binocular camera and single point laser rangefinder

作　　者：储昭碧[1] 李子朋 高金辉 Chu Zhaobi;Li Zipeng;Gao Jinhui(School of Electrical Engineering and Automation,Hefei University of Technology,Hefei 230009,China)

机构地区：[1]合肥工业大学电气与自动化工程学院,合肥230009

出　　处：《仪器仪表学报》2023年第5期232-239,共8页Chinese Journal of Scientific Instrument

基　　金：安徽省科技重大专项(202103a05020001)资助。

摘　　要：近年来,随着工业机器人技术的不断完善,利用相机与激光测距仪结合测量的应用不断增多。为了使两者之间配合的更加便利,两者之间的标定是必不可少的。本文提出了一种基于双目相机与单点激光测距仪的标定方法,以双目相机光心为原点,建立相机坐标系。将单点激光测距仪光点打到标定板上,并在标定板上形成光斑,通过灰度重心法提取光斑中心像素点,利用双目相机的内参矩阵及深度数据获取光斑点的三维坐标值。然后利用两个三维坐标点建立公式求取外参参数的粗略解,同时通过相机坐标系下多个光斑点的三维坐标建立约束方程,并利用优化算法对约束方程进行优化,得到精确的外参参数值。该方法做法简单,且对标定器件无特殊要求,通过该方法得到的外参参数精度高,鲁棒性好。实测结果表明,通过该算法得到的外参参数进行重投影后,平均相对误差小于0.30%,能够应用于实际生产过程中。In recent years,with the continuous improvement of industrial robot technology,the application of combining camera and laser rangefinder for measurement is increasing.To facilitate the coordination between the binocular camera and the single point laser rangefinder,calibration between them is essential.This article proposes a calibration method of binocular camera and single point laser rangefinder.The light spot of the single point laser rangefinder is hit on the calibration board,and the light spot is formed on the calibration board.The pixel point at the center of the light spot is extracted by the gray center of the gravity method,and the three-dimensional coordinate value of the light spot is extracted by using the internal parameter matrix and depth data of the binocular camera.Then,two three-dimensional coordinate points are used to establish formulas to obtain the rough solution of the external parameter parameters.Meanwhile,the constraint equations are established through the three-dimensional coordinates of multiple light spots in the camera coordinate system,and optimization algorithms are used to optimize the constraint equations to obtain accurate external parameter values.This method is simple and has no special requirements for calibrating devices.The external parameters obtained through this method have high accuracy and good robustness.The actual measurement shows that the average relative error of the external parameter parameters obtained through this algorithm after re-projection is less than 0.30%,which can be applied in actual production process.

关 键 词：双目相机 单点激光测距仪 传感器标定 优化算法 

分 类 号：TH74[机械工程—光学工程]