表面测量中高斯滤波中线的有理逼近实现  

Rational approximation implementation approach to determine Gaussian filtering mean line in surface roughness measurement

作　　者：许景波[1,2] 袁怡宝[3] 崔晓萌[1,2] 郭欣[1,2] 王升[1,2] 

机构地区：[1]哈尔滨理工大学测控技术与通信工程学院,哈尔滨150080 [2]测控技术与仪器黑龙江省高校重点实验室,哈尔滨150080 [3]哈尔滨工业大学自动化测试与控制系,哈尔滨150001

出　　处：《吉林大学学报（工学版）》2014年第5期1347-1352,共6页Journal of Jilin University:Engineering and Technology Edition

基　　金：黑龙江省教育厅科学技术研究项目(11541053)

摘　　要：通过有理分式逼近提出了一种高斯滤波器实现方法。由有理分式模型,根据插值逼近方法确定相应系数,得出的有理逼近分式具有较高的逼近精度,与理论高斯滤波器最大幅度偏差为0.88%,截止频率内的幅度偏差小于2‰,是优化的逼近函数。由逼近分式S域左半平面极点建立逼近滤波器,由后向差分变换得出Z域模型,并应用零相移滤波技术得出了零相移数字滤波算法,满足了表面测量中对高斯滤波器实现方法的相位要求。应用这一方法,建立了表面轮廓中线,分离出表面粗糙度数据,整个算法只经一级零相移滤波就能完成,具有较高的计算效率,为表面测量高斯滤波的实现提供了一种新的方法。Based on rational fraction approximation, an implementation approach for Gaussian filter is presented. The coefficients in the rational fraction are determined by interpolation approximation. The deduced rational fraction is an optimization approximation function with high approximation accuracy. The maximum amplitude deviation from theoretical Gaussian filter is 0.88% in the whole frequency domain, and is less than 2‰ in cutoff frequency. The approximation filter is designed by the poles in the left half plane of S domain, and the corresponding digital filter in Z domain is obtained by backward difference transformation. The corresponding zero-phase-shift digital filtering algorithm is achieved by zero-phase-shift technique that meets the requirements of surface measurement. This method is applied to surface roughness measurement to determine the mean line of surface profile and separate surface roughness. The algorithm has high computation efficiency because it can be implemented by only one stage zero-phase-shift filtering, and provides a new method for surface measurement.

关 键 词：表面粗糙度测量 高斯滤波器 有理逼近 零相移滤波 

分 类 号：TB92[一般工业技术—计量学]