Automated modal identification by quantification of high-spatial-resolution response measurements.

Identifying modal parameters from vibration measurements is an essential step for modal analysis and modeling of structural dynamics. A critical challenge in modal parameter identification is the determination of the physical modes from spurious modes, especially with noisy measurement data. In this study, an approach is presented to enable automated identification of modal parameters by quantifying the spatial features of full-field, high-spatial-resolution response measurements. Specifically, it is derived that the local variances of the physical and spurious mode shapes are drastically distinguishing, especially when the spatial resolution of the response measurement is high (i.e., full-field with dense spatial measurement points). This allows an effective identification of the physical modes from spurious. Experimental studies are conducted on a few structural models and detailed comparisons are performed and discussed between the presented method and existing methods, including parametric and non-parametric. • A new approach for automatically distinguishing spurious and physical modes. • Full-field measurements allow spatial and statistical analysis of mode shapes. • Local variances of physical and spurious mode shapes form well-separated clusters. • Performance is compared to existing methods both numerically and experimentally. [ABSTRACT FROM AUTHOR]