A Modification to Unified Matrix Polynomial Approach (UMPA) for Modal Parameter Identification

Abstract

In this paper, a modification to Unified Matrix Polynomial Approach (UMPA) for modal parameter identification of mechanical systems is suggested. Following the proposed modification, the measured Frequency Response Functions (FRF)/Impulse Response Functions (IRF) matrices of the system are manipulated so that the vibrational modes of the system can be identified at smaller model orders. A multi degree of freedom numerical case study and the experimental data of a circular plate are then employed to investigate the enhancement in performance of UMPA framework due to the proposed modification. It will be shown that following the proposed data manipulation, matrices with large values of condition number can be avoided in modal parameter estimation.