基于区域灰度梯度差异的摆片基片特征尺寸视觉测量方法  

A visual measurement method for feature size of pendulum substrate based on regional gray gradient difference

作　　者：许斌[1] 徐凡颖 辛若铭 Xu Bin;Xu Fanying;Xin Ruoming(School of Mechanical Engineering,Sichuan University,Chengdu 610044,China)

机构地区：[1]四川大学机械工程学院,成都610044

出　　处：《仪器仪表学报》2022年第5期128-135,共8页Chinese Journal of Scientific Instrument

摘　　要：石英摆片是石英挠性加速度计的核心器件,其关键特征尺寸的加工精度由摆片基片加工精度决定。常规使用工具显微镜对基片表面特征尺寸进行测量,此测量过程复杂、重复性精度弱且效率低。提出了基于区域灰度梯度差异的摆片基片特征尺寸测量方法。首先对视觉测量系统硬件结构进行了设计研制,然后建立了基于区域灰度梯度的摆片基片边缘检测算法,其次围绕摆片基片结构特点提出了其特征边缘点的搜索分类方法,最后开展了摆片基片特征尺寸测量实验。实验结果表明,提出边缘检测方法在摆片基片圆心拟合偏差小于3μm的情况下可替代Zernike矩方法以提高边缘检测效率;所研测量系统2 s内即可完成摆片基片特征尺寸测量且不同位姿下的摆片基片特征尺寸测量重复性精度优于8μm。相较于工具显微镜,测量结果可靠性及重复性均有所改善,测量效率显著提升。Quartz pendulum reed is the core device of the quartz flexible accelerometer,and the machining accuracy of its key feature size is determined by the machining accuracy of the pendulum substrate.The feature size of the substrate surface is routinely measured with a tool microscope.This measurement process is complex,with poor repeatability and low efficiency.In this article,a method for measuring the feature size of the pendulum substrate based on the regional gray gradient difference is proposed.Firstly,the hardware structure of the visual measurement system is designed and developed.Secondly,the edge detection algorithm of the pendulum substrate based on the regional grayscale gradient is established.Thirdly,the search and classification method of the feature edge points is proposed around the structural characteristics of the pendulum substrate.Finally,the feature size measurement experiment of the pendulum substrate is carried out.Experimental results show that the proposed edge detection method based on regional gray gradient can replace the Zernike moment method to improve the edge detection efficiency when the fitting deviation of the center of the pendulum substrate is less than 3 μm.The measurement system can complete the measurement of the characteristic size of the pendulum substrate within 2 s,and the repeatability of the measurement of the characteristic size of the pendulum substrate in different postures is better than 8 μm.Compared with the tool microscope,the reliability and repeatability of the measurement results are improved,and the measurement efficiency is significantly improved.

关 键 词：摆片基片 边缘检测 特征搜索 视觉测量 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术] TH701[自动化与计算机技术—计算机科学与技术]