基于莫尔条纹的全周转角精密测量方法  

Precision measurement method of full-cycle torsion angle based on Moiréfringe

作　　者：许令鸿 张秋坤[1] 林杰文[1] 李劲林 黎昕婷 钟舜聪[1] XU Linghong;ZHANG Qiukun;LIN Jiewen;LI Jinlin;LI Xinting;ZHONG Shuncong(College of Mechanical Engineering and Automation,Fuzhou University,Fuzhou 350108,China)

机构地区：[1]福州大学机械工程及自动化学院,福建福州350108

出　　处：《应用光学》2024年第3期644-651,共8页Journal of Applied Optics

基　　金：国家自然科学基金资助项目(52275096);福建省科技重大专项(2022HZ024005)。

摘　　要：由于将莫尔条纹图进行快速傅里叶变换时会导致频谱泄露,导致无法实现360°的全周精确测量,因此提出基于莫尔条纹的全周转角测量方法并搭建转角测量系统。以1°为步距,利用CMOS相机采集不同宽度的莫尔条纹图像,采用快速傅里叶变换(fast Fourier transform,FFT)对条纹进行处理,得到光栅频谱信息。同时采用汉宁窗能量重心校正算法(Hanning-window energy centrobaric method,HnWECM)校正频谱,得到莫尔条纹图像表征转角的真实有效信息,实现全周精确测量。实验结果表明,该系统可快速精准地实现转角的全周测量,测量范围广,最大误差率为0.2433%。Due to the leakage of frequency spectrum caused by applying fast Fourier transform to the Moiréfringe image,it becomes challenging to achieve accurate 360°full-cycle measurements.A measurement method of full-cycle torsion angle based on Moiréfringe was proposed and a set of torsion angle measurement system was built.The Moiréfringe images with different widths were acquired by a CMOS camera at 1°intervals,and then the grating frequency spectrum information could be obtained by adopting fast Fourier transform(FFT).In addition,the frequency spectrum was corrected by the Hanning-window energy centrobaric method(HnWECM),and the real and effective information of torsion angle represented by Moiréfringe image could be obtained to achieve precision measurement of full-cycle torsion angle.Experimental results show that the system can quickly and accurately realize the full-cycle measurement of the torsion angle with the advantage of wide measurement range,and its maximum error rate is 0.2433%.

关 键 词：转角测量 莫尔条纹 快速傅里叶变换 汉宁窗能量重心法 

分 类 号：TN06[电子电信—物理电子学] TB22[天文地球—大地测量学与测量工程]