基于二维混合式位置编码的高精度测角  

High-precision angle measurement based on two-dimensional hybrid position encoding

作　　者：赵会宁[1,2] 闻杰 夏豪杰 ZHAO Huining;WEN Jie;XIA Haojie(School of Instrument Science and Opto-electronics Engineering,Hefei University of Technology,Hefei 230009,China;Anhui Province Key Laboratory of Measuring Theory and Precision Instrument,Hefei 230009,China)

机构地区：[1]合肥工业大学仪器科学与光电工程学院,安徽合肥230009 [2]测量理论与精密仪器安徽省重点实验室,安徽合肥230009

出　　处：《光学精密工程》2024年第5期635-642,共8页Optics and Precision Engineering

基　　金：国家重点研发计划资助项目(No.2022YFF0705702);国家自然科学基金资助项目(No.51805139,No.51975180)。

摘　　要：针对具有精密旋转轴系类的高端制造装备或精密测量仪器,其旋转角度采用传统圆光栅难以消除偏心误差对测量角度精度的影响,提出了一种基于二维混合式位置编码的旋转角度高精度测量方法。该测角系统由一个二维混合式位置编码盘、两个CCD相机和远心镜头组成,二维混合式位置编码盘被固定在精密旋转轴系上以获得其旋转角度。然后,建立了测角模型并从数学上证明了测角精度与安装偏心无关。利用多齿分度台对已提出测角系统精度进行检测,测量角度误差在±1″。最后,利用已提出测量方法对直驱转台的角度定位精度进行测量,角度定位误差在±5″内。与传统圆光栅测角相比,该方法不需要考虑安装偏心误差对测角精度的影响,具有稳定性好、使用简单等特点,可用于角度定位误差的检测。For high-end manufacturing equipment or precision measurement instruments featuring precision rotating shafting,traditional circular grating struggles to negate the impact of eccentricity error on angle measurement accuracy.This paper introduces a highly precise method for measuring rotation angles utilizing two-dimensional hybrid position coding.Initially,the system comprises a two-dimensional hybrid position coding disk,two CCD cameras,and a telecentric lens.This assembly is attached to a precision rotating shaft to capture its rotation angle.Subsequently,an angle measurement model is developed,mathematically verifying that measurement accuracy remains unaffected by installation eccentricity.The method's accuracy is validated using a multi-tooth indexing table,confirming that angle measurement error is confined to within±1".Furthermore,when applied to assess the angle positioning accuracy of a direct drive turnta‑ble,the method achieves an angle positioning error within±5".Unlike traditional circular grating measure-ments,this approach eliminates the need to account for the impact of eccentricity error on accuracy,offer-ing robustness and simplicity in application.Thus,it proves effective for detecting angle positioning errors.

关 键 词：二维混合式位置编码 偏心误差 旋转角度 多齿分度台 

分 类 号：TH712[机械工程—测试计量技术及仪器]