基于压缩感知的兰姆波下采样和损伤定位  

Lamb Wave Down-Sampling and Damage Location Based on Compressed Sensing

作　　者：程涛[1] 杨明 吴小龙 CHENG Tao;YANG Ming;WU Xiao-long(School of Mechanical and Transportation Engineering,Guangxi University of Science and Technology,Guangxi Liuzhou 545006,China)

机构地区：[1]广西科技大学机械与交通学院,广西柳州545006

出　　处：《机械设计与制造》2024年第4期77-80,共4页Machinery Design & Manufacture

基　　金：基于压缩感知的定向遥感理论研究(41461082);基于压缩感知的超分辨显微成像理论研究(81660296)。

摘　　要：一种基于压缩感知和兰姆波的损伤检测方法利用兰姆波下采样信号构造测量矩阵,需要恰当的采样率才能使测量矩阵行数小于列数,从而满足压缩感知的适用条件。但是,过低的采样率会导致采集到的接收信号与真实信号严重失真。针对这一问题,提出基于插值的计算下采样信号与真实信号相关系数的方法,判断下采样信号与真实信号的失真程度。并结合压缩比,选择合适的采样间隔,确定测量矩阵。通过对测量矩阵做行正交规范化处理,优化测量矩阵,大大提高重构效果和损伤定位精度及能力。优化后,重构概率为1的稀疏度由1增长到12左右。A Damage detection method based on compressed sensing and Lamb wave is used to construct a measurement matrix based on the Lamb wave subsampling signals,and an appropriate sampling rate is required to make the number of rows of the measurement matrix less than the number of columns.,so as to meet the applicable conditions of compressed sensing.However,a too low sampling rate will cause serious distortion between the received signal and the real signal.For this problem,a method based on interpolation to calculate the correlation coefficient between the down-sampled signal and the real signal is proposed to determine the degree of distortion between the down-sampled signal and the real signal.And combined with the compression ra-tio,the appropriate sampling interval is selected,the measurement matrix is determined.Through the orthogonal normalization of the measurement matrix,the measurement matrix is optimized,which greatly improves the reconstruction effect and the accu-racy and ability of damage location.After optimization,the sparsity with a reconstruction probability of 1 increases from 1 to about 12.

关 键 词：压缩感知 兰姆波 损伤定位 下采样 测量矩阵 

分 类 号：TH16[机械工程—机械制造及自动化] TP391[自动化与计算机技术—计算机应用技术]