Evaluating tool point dynamics using output-only modal analysis with mass-change methods

摘要: Abstract This paper discusses the evaluation of tool point dynamics using output-only modal analysis methods. As compared to traditional experimental procedures that rely on input and output, both being known, methods discussed herein can evaluate parameters only measured response subjected unknown impact-based excitations. Since is not estimated shapes are unscaled. To correctly scale shapes, we use mass-change method. We present analytical models guide optimal selection mass be added as well its placement tool. Analytical systematically characterize errors in scaling eigenvector due uncertainties estimation natural frequencies. The model suggests at anti-node(s) for mode(s) interest. These experiments two tools – a slender boring bar, an end mill. Tool frequency functions (FRFs) reconstructed with frequencies, damping ratios, scaled mode evaluated method found good agreement FRFs obtained from procedures. require one less transducer, since these robust inconsistencies input, promise advantages industrial view.