基于光学自准直的旋转轴平行度测量与不确定度分析  

Coaxiality measurement and uncertainty analysis of rotating shafts based on autocollimation

作　　者：李小明[1,2] 朱国帅 郭名航 刘赢泽 张崇 Li Xiaoming;Zhu Guoshuai;Guo Minghang;Liu Yingze;Zhang Chong(National and Local Joint Engineering Research Center of Space and Optoelectronics Technology,Changchun University of Science and Technology,Changchun 130022,China;College of Mechanical and Electronic Engineering,Changchun University of Science and Technology,Changchun 130022,China;The First Military Representative Office,Shenyang Military Representative Bureau of PLA,Army Equipment Department in Changchun,Changchun 130022,China)

机构地区：[1]长春理工大学空间光电技术国家地方联合工程研究中心,吉林长春130022 [2]长春理工大学机电工程学院,吉林长春130022 [3]中国人民解放军陆军装备部驻沈阳地区军事代表局驻长春地区第一军事代表室,吉林长春130022

出　　处：《红外与激光工程》2023年第5期304-315,共12页Infrared and Laser Engineering

基　　金：航空科学基金(202000080Q8001);吉林省教育厅产业优化研究项目(JJKH20220756CY)。

摘　　要：在激光通信和光电跟瞄系统中已经开始采用基于旋转光栅或光楔的指向-捕获-跟踪(Pointing,acquisition and tracking,PAT)机构对光轴进行角度调整,该结构质量轻、体积小,非常有利于系统的轻小型化。由于结构中两个旋转轴的平行度误差会严重影响PAT机构性能,因此在机械装配时需严格保证两轴平行度。针对旋转轴系轴线不易测量,传统测试方法精度不足,轴系晃动误差影响测量结果等问题,为了满足两轴平行度高精度检测的需求,文中提出基于自准直原理的旋转轴平行度测试方法,利用自准直光学特性,结合特殊设计的半反半透基准镜,采用数据拟合方法剔除轴系晃动的影响,得到旋转轴轴线空间位置,创新地实现了无需调整测试和被测设备即可在同一基准下测量两个平行轴系轴线角度和平行度。该方法只需一台测试设备,排除了传统多台测试设备联合测量时,基准传导与变换中的测量和变换误差,提高了测试精度和测试效率。首先,设计了基于自准直仪的测试系统,采用一台自准直仪测试两个轴系轴线空间位置,从而得到旋转轴同轴误差;然后,对测试结果不确定度进行了研究,分析了测试准确性及其影响因素;最后,采用该测试方法和测试系统,对某双液晶光栅跟瞄PAT机构的两轴平行度进行了测量,系统的实际测试表明两轴平行度测试误差小于10%,该方法可以有效地测量两个同轴旋转轴系的平行度,并且具有较高的测量精度和可信度。Objective In laser communication and photoelectric tracking systems,the pointing,acquisition and tracking(PAT)mechanism based on optional grating or wedge has been used to adjust the angle of the optical axis.This structure is light in weight and small in size,which is very beneficial to the lightweight and miniaturization of the system.Since the coaxiality error of the two rotating axes of the structure seriously affect the performance of the PAT mechanism,it is necessary to strictly ensure the parallelism of the two axes during mechanical assembly.For the cross-tracking frame gimbal,the precision of shafting angle position depends on the verticality of two axes,which can be measured by autocollimator with optical mirror.But in optional grating or wedge PAT system,the gimbal is characterized by two rotating axes coaxially arranged to drive two gratings to rotate respectively,and the test method for cross-tracking frame gimbal is not applicable.The existing parallelism measurement methods,such as contact measurement and non-contact measurement,are straight-line measurements,contact measurement includes micrometer measurement and three-coordinate measurement,and the required angular deviation between two rotating axes of a coaxial turntable can be obtained only after data conversion.When the diameter of the distribution circle is small,its accuracy is low,and there are problems such as inconsistent conversion standards,poor conversion data accuracy,and low confidence.Therefore,it is necessary to establish the methods for angle parallelism measurement of grating or wedge PAT system with high precision,high reliability and high convenience to solve the engineering problems in the process of gimbal test and assembly.Methods A non-contact optical measurement method is proposed,and it uses an autocollimator as the only reference to measure the axis angle of two coaxial shafting without moving the autocollimator and the test gimbal in the test(Fig.4).Data processing is used to eliminate the influence of shafting sloshin

关 键 词：PAT 平行度 数据拟合 不确定度 旋转轴系 

分 类 号：TH741[机械工程—光学工程]