摘要
针对轴径测量问题,提出一种通过建立与轴线垂直的虚拟平面,并利用基于最小二乘圆拟合算法快速获得被测轴直径的方法。对线结构光视觉系统进行标定,得到摄像机的内参、畸变系数、结构光平面参数;获得被测回转体轴线的方向向量和轴线与结构光平面交点坐标,利用已得到的方向向量和轴线与结构光平面的交点建立一个与轴线垂直的虚拟平面;再将结构光平面与零件表面上的交点投影到虚拟平面上,并通过所有投影点到轴线与光平面交点的距离排除数据中的噪点;最后利用有效投影点和轴线与光平面交点的距离,得到被测回转体的外表面圆柱度。通过轴径测量试验对该算法进行了验证,在复杂的测量环境下,当被测轴直径为30~50 mm时,平均测量误差为30μm,最大测量误差为50μm。因此,该算法可以应用于实际回转体零件的直径测量中。
A virtual plane perpendicular to the axis was proposed,and the diameter of the measured axis was obtained quickly by using the least square circle fitting method.The linear structured light vision system was calibrated to obtain the camera’s internal parameters,distortion coefficient and plane parameters of the structured light.The direction vector of the axis of the measured rotation body and the intersection point of the axis with the structural light plane were obtained,and the obtained direction vector of the axis and the intersection point of the axis with the structural light plane were used to establish a virtual plane perpendicular to the axis.The intersection points of the structure light plane and the surface of the part were projected onto the virtual plane,and the noise points in the data were eliminated by the distance from all projection points to the axis and the intersection points of the light plane.Finally,using the effective projection point and the distance between the axis and the intersection point of the optical plane,the cylindricity of the outer surface of the measured rotating body was obtained.The proposed algorithm was verified through the axial measurement experiment.In the complex measurement environment,when the diameter of the shaft under test is 30~50 mm,the average measurement error is 30μm and the maximum measurement error is 50μm.Therefore,the proposed algorithm can be applied to the diameter measurement of practical rotary parts.
作者
张翠翠
刘思远
赵京鹤
ZHANG Cuicui;LIU Siyuan;ZHAO Jinghe(College of Mechanical Engineering,Changchun Guanghua University,Changchun Jilin 130033,China;College of Mechanical and Aerospace Engineering,Jilin University,Changchun Jilin 130022,China)
出处
《机床与液压》
北大核心
2021年第17期132-136,共5页
Machine Tool & Hydraulics
关键词
线结构光
视觉检测
系统标定
轴径测量
畸变
Line-structured light
Visual inspection
System calibration
Shaft diameter measurement
Distortion
