基于三维激光扫描的H型钢尺寸误差与接长精度技术研究

Research on Dimensional and Docking Accuracy Technology of H-shaped Steel Based on 3D Laser Scanning

H型钢具有良好的强度、灵活多样的连接方式、结构重量轻等多种优势,在海洋工程、陆地结构工程大量使用,对其制造精度有较高要求。大部分大型H型钢通过钢板焊接而成,由于焊接变形的影响,其长度方向、腹板和翼缘板都存在不同程度的变形,目前采用的是人工钢丝拉线测量方法,通过卡尺逐点测量,效率低、精度差。本文利用三维激光扫描对大型H型钢进行扫描,形成不同坐标系下的点云数据,将多坐标系的点云数据进行空间转换和拼接等处理,形成归一化的H型钢三维空间点云模型;利用平面误差分析算法、结构特征轴线拟合、二维投影直线拟合等方法对H型钢的点云数据进行特征分析,形成H型钢尺寸精度评判模型,进而对H型钢的平面度和对接精度进行分析,形成相关的拟合方程,该方法具有效率高,精度高等特点,对使用H型钢的相关工程有重要的意义。

H-beam has many advantages,such as good strength,flexible and varied connection mode,light weight and so on.It is widely used in ocean engineering and land structure engineering.Due to the influence of welding deformation,the length direction,webs and flange plates of most large h-section steel are deformed to different degrees,through the caliper point by point measurement,low efficiency,poor precision.In this paper,three-dimensional laser scanning is used to scan large h-beam to form point cloud data in different coordinate systems,a normalized point cloud model of h-beam 3D was developed,and the characteristics of the point cloud data of h-beam were analyzed by the methods of plane error analysis algorithm,structure feature Axis fitting,and two-dimensional projection line fitting,then the flatness and docking precision of H-beam are analyzed,and the relevant fitting equations are formed.This method has the characteristics of high efficiency and high precision,it is of great significance to the related projects using h-beam.