光笔视觉测量系统的精确测量研究  

Research on accurate measurement of light pen vision measurement system

作　　者：李为民[1] 许康康 LI Weimin;XU Kangkang(Department of Precision Machinery and Precision Instrumentation,University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]中国科学技术大学精密机械与精密仪器系,安徽合肥230026

出　　处：《传感器与微系统》2024年第7期27-31,共5页Transducer and Microsystem Technologies

摘　　要：光笔视觉测量系统是以光笔为接触式辅助测量工具的一种便携式坐标测量系统,具有便携性好、测量范围大、精度高等优点。但在接触式测量过程中,记录的是测头中心坐标,需要对测头进行半径补偿。结合光笔式测量系统,提出一种针对散乱点云进行半径补偿的可行性方法。利用点云的网格化处理,寻找散乱点云中点的拓扑关系,得到局部点云的矩形拓扑网格。使用拓扑网格点进行NURBS曲面插值拟合,得到网格中心点的法向量。实验表明,该方法求得的法向量误差角度在0.5°左右,测头半径为2.5mm情况下,测量误差在0.030mm以下。Light pen visual measurement system is a portable coordinate measuring system that employs a light pen as a contact-assisted measurement instrument.Its benefits include good portability,wide measuring range and high precision,etc.The center coordinates of probe are recorded during the process of contact measurement;thus,the radius of the probe must be compensated.A feasible radius compensation method for unorganized point cloud is proposed by combining a light pen type measurement system.Grid processing of the point cloud is used to discover topological relationships between the points in the unorganized point cloud and obtain rectangular topological grid of local point cloud.In addition,the normal vectors of the central points of grid are obtained by fitting the NURBS curve surface interpolation based on the topological grid points.Experiments show that the obtained normal vector error angle is about 0.5°,and when the probe radius is 2.5 mm,the measurement error is below 0.030 mm.

关 键 词：半径补偿 散乱点云 NURBS曲面插值 光笔 

分 类 号：TH741[机械工程—光学工程]