Application of Structured Low Rank Approximation in Modal Analysis

Abstract

The quality of measured vibration response signals is adversely affected by noise in modal testing. This situation often leads to serious difficulties in estimating the modal parameters with proper accuracy. This paper presents a signal de-noising method for measured impulsive response functions (IRFs) based on structured low rank approximation (SLRA) so as to improve the accuracy of the modal parameters identification. The proposed method is verified by simulation study of a cantilever beam. The results show that this method can eliminate noise from measured IRFs efficiently, and significant improvement in modal parameters estimation could be obtained based on the filtered IRFs.