基于变换序列权重峰值拟合的直线电机速度的快速精密测量  

Rapid-precision velocity measurement of linear motor based onweighted peak fitting of transformed sequence

作　　者：赵静[1] 王婉婉 周杨 董菲[1] ZHAO Jing;WANG Wanwan;ZHOU Yang;DONG Fei(College of Electrical Engineering and Automation,Anhui University,Hefei 230601,China)

机构地区：[1]安徽大学电气工程与自动化学院,安徽合肥230601

出　　处：《光学精密工程》2022年第5期574-583,共10页Optics and Precision Engineering

基　　金：安徽省教育厅重点项目(No.KJ2021A0009);国家自然科学基金资助项目(No.51707002,No.51907001);安徽省自然科学基金资助项目(No.1808085QE123)。

摘　　要：为了实现直线电机动子速度的实时鲁棒精密测量,研究了一种基于权重相位相关峰值拟合的直线电机速度测量方法。首先,构造出锯齿波条纹目标图像,利用线扫描相机获取运动过程中的连续锯齿波条纹序列。然后,采用相位差算法得到相邻信号的互功率谱,引入反比例函数代替傅里叶反变换后的狄拉克函数,仅通过对峰值点及两个邻域点简单加权,更加快速稳定得到条纹信号的亚像素位移。最后,根据系统标定系数和固定拍摄间隔计算直线电机动子实时速度。实验结果表明:本文方法的平均耗时约为0.02 ms,测量精度在0.05 pixel以内,速度测量精度为0.03 mm/s。To achieve real-time robust precision measurement of linear motor velocity,a measurement method based on weighted phase correlation peak fitting was proposed in this study.First,a sawtooth stripe target image was constructed,and a continuous sawtooth fringe sequence was obtained by using a line scan camera installed on the side of the mover.Then,a phase difference algorithm was used to determine the cross power spectrum of the adjacent signals,and an inverse proportion function was introduced by applying the Fourier inverse transform to the Dirac function.To obtain the sub-pixel displacement of the fringe signal more quickly and stably,simple weighting was applied to the peak point and two neighboring points.Finally,the real-time velocity of the linear motor was calculated based on the system calibration coefficient and a fixed shooting interval.The experimental results show that the average time required by this method is approximately 0.02 ms,with a measurement accuracy within 0.05 pixel and an accuracy of velocity measurement of 0.03 mm/s.

关 键 词：直线电机 图像测速 锯齿波条纹图像 权重相位相关峰值拟合 亚像素测量 

分 类 号：TH82[机械工程—仪器科学与技术] TM301[机械工程—精密仪器及机械]