VT-910 Visual OMA Pro™

The Visual OMA Pro™ package combines the features of the Visual Modal Pro™ package with the features of the VES-4700 Operational Modal Analysis option.  For cases where the excitation forces cannot be measured and output-only responses are acquired, modal parameters can still be extracted from a set of specially processed Cross Spectra or ODS FRFs. The Operational Modal Analysis option adds special windowing and other features to the Visual Modal Pro™package, thus providing a complete set of tools for extracting modal parameters from measurements made in any type of testing environment.

Visual OMA Pro™ Features

  • Deconvolution When this window is applied to a set of Cross Spectra or ODS FRFs, operational modal parameters can be extracted from them using FRF-based curve fitting methods
  • Mode shape scaling. A modal model (a scaled set of mode shapes) can be created from a set of output-only operational mode shapes
  • Mode counting to identify closely coupled modes & repeated roots using either the Multi-Reference Complex Mode Indicator Function (CMIF), or the Multi-Reference Multivariate Mode Indicator Function (MMIF)
  • Curve fitting using the Multiple Reference Orthogonal Polynomial method
  • Multi-Reference Quick Fit. Automatically executes three curve fitting steps (count modes, estimate frequency & damping for each mode, estimate residues for each mode) with minimal user interaction
  • Multi-Reference curve fitting using a Stability diagram and either the Z-Polynomial curve fitting method, the Complex Exponential curve fitting method, or the Alias-Free Polynomial (AF Poly) curve fitting method
  • Stability A graphical display of frequency & damping estimates (poles) in differently colored stable pole groups. All poles are calculated using curve fitting model sizes ranging from 1 to a user-defined maximum
  • Stable Poles A graphical display of poles (frequency & damping estimates) in differently colored stable pole groups
  • Stable Pole Group. A group of solutions on a Stability or Poles diagram that satisfy a user-defined minimum number of poles that lie within user-defined frequency & damping tolerances
  • Shape Complexity Plot. A graphical display of the complex shape components of one or more mode shapes
  • Shape Component Magnitude Ranking. A graphical display of the ordered magnitudes of the shape components of each mode shape
  • Shape Expansion. A set of shapes with many DOFs is curve fit to a set of shapes with few DOFs, to create new shapes with many DOFs in them
  • Poles A graph of the modal frequency & damping estimates (poles) of a set of mode shape