正交三维扫描测头标定的多区域变参数法研究

摘要

To solve coupling of 3D orthogonal scanning probe among three detecting directions, a calibration method based on multiregion and variable parameters coefficient matrix is presented. The 3*3 calibration matrix is used in calibration process, and the standard ball is divided into four basic areas according to the probe deformations. Let the probe contact several points planned on different areas of the standard ball and approach continuously to every point, and a number of data of the probe and linear grating are collected to establish a calibration equation, then four calibration matrices are so obtained with the least square method, and high-precise calibration for 3D orthogonal scanning probe can be finally achieved. The calibration results are experimentally verified with other two methods, which shows the higher calibration rate and precision. This study may offer a foundation for the high-precise measurement of 3D orthogonal scanning probe.%针对正交三维扫描测头的3个探测方向间存在着相互干涉,即耦合的问题,提出了一种基于多区域变参数系数矩阵的正交三维扫描测头标定方法.运用3×3系数矩阵对测头进行标定,该方法依据测头变形量的正负将标准球划分为4个基本区域,通过控制测头接触标准球上不同区域中的若干探测点,在每个探测点上向标准球球心方向连续步进测量,利用两者变化量之间的关系建立标定方程,运用最小二乘方法确定出4个标定矩阵,实现了正交三维扫描测头的高精度标定.采用2种方法对标定结果进行了实验验证,实验结果表明,多区域变参数系数矩阵的标定方法是可行的,具有标定快速、准确的优势,为正交三维扫描测头的高精度测量奠定了坚实的基础.