基于激光和CCD组合的小孔转轮重复定位精度测量方法  

Measurement method of repeated positioning accuracy of pinhole runner based on combination of laser and CCD

作　　者：梁为育 叶超[1] 胡秋[1] 刘盛[1] LIANG Weiyu;YE Chao;HU Qiu;LIU Sheng(Institute of Mechanical Manufacturing and Technology,China Academy of Engineering Physics,Mianyang 621900,China)

机构地区：[1]中国工程物理研究院机械制造工艺研究所,四川绵阳621900

出　　处：《应用光学》2021年第5期919-925,共7页Journal of Applied Optics

基　　金：国家科技重大专项(2017ZX04022001);中国工程物理研究院创新发展基金(K1189)。

摘　　要：小孔转轮是某试验装置光路自动校准系统的关键器件,重复定位精度是其重要指标之一。为了有效测量运行于真空环境下的小孔转轮重复定位精度,提出了一种基于激光和CCD组合的测量方法,并以转轮滤波小孔光斑中心的位置重复性作为其重复定位精度的评价指标,搭建了一套完整的测量系统。利用CCD采集通过转轮滤波小孔的激光光斑,通过图像处理的方法对激光光斑图像进行滤波去噪、阈值分割、二值化、边缘检测等预处理,利用最小二乘法对激光光斑进行圆拟合,得到光斑中心坐标。在非真空环境下与激光干涉仪进行了对比实验,两者测量的角度偏差仅相差11″,表明了该测量方法具有较高的精度,可以满足测量要求。采用该测量方法对真空环境下的小孔转轮进行了约6 h正反往复各60次的重复性测量,结果表明,该测量方法能有效测量真空环境下小孔转轮的重复定位精度。The pinhole runner is the key component of the optical-path automatic calibration system of an experimental device,and the repeated positioning accuracy is one of its important indexes.In order to effectively measure the repeated positioning accuracy of the pinhole runner in vacuum environment,a measurement method based on the combination of laser and charge coupled device(CCD)was proposed,and the position repeatability of laser spot center of runner filtering pinhole was taken as the evaluation index of its repeated positioning accuracy.A complete set of measurement system was built,the laser spot filtered through the runner filtering pinhole was collected by CCD,and the laser spot image was preprocessed by the image processing methods,such as filtering and noise reduction,threshold segmentation,binarization and edge detection.The least square method was used for circle fitting of the laser spot,and the center coordinates of laser spot were obtained.Compared with laser interferometer in non-vacuum environment,the angular deviation between them was only 11″,which showed that the measurement method had high accuracy and met the measurement requirements.Finally,the repeatability measurement of the pinhole runner in vacuum environment was carried out for about 60 times forward and backward reciprocation in about 6 hours.The results show that the method can effectively measure the repeated positioning accuracy of the pinhole runner in vacuum environment.

关 键 词：激光 CCD 小孔转轮 重复定位精度 图像处理 最小二乘法 

分 类 号：TN249[电子电信—物理电子学]