Using Laser Vibrometry for Precise FRF Measurements in Experimental Substructuring

  • Francesco TrainottiEmail author
  • Tobias F. C. Berninger
  • Daniel J. Rixen
Conference paper
Part of the Conference Proceedings of the Society for Experimental Mechanics Series book series (CPSEMS)


The acquisition of high quality FRF measurements is a key factor for a successful implementation of coupling/decoupling techniques in Experimental Dynamic Substructuring. Although the use of piezo accelerometers as response transducers is very popular for impact testing due to its easy and fast implementation, the level of accuracy could not be adequate in certain applications. The laser technology provides a non-invasive alternative to standard piezo devices. The choice of a non-contact measurement technique allows to minimize the impact of external dynamic systems on the test component during the measurement process. In this paper, a validation of Lagrange Multiplier—Frequency Based Substructuring coupling by means of a Virtual Point Reduction is performed on a benchmark structure with a non-stiff interface. The necessary FRF data is acquired twice, using accelerometers and a laser Doppler vibrometer respectively. Both coupling results are compared to each other and are shown to match very well simulation data up to a high frequency range. The results underline the potential of high quality, non-intrusive measurements for Frequency Based Substructuring.


Experimental dynamics Dynamic Substructuring Frequency Based Substructuring Virtual Point Transformation FRF measurements Laser vibrometry 


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Copyright information

© Society for Experimental Mechanics, Inc. 2020

Authors and Affiliations

  • Francesco Trainotti
    • 1
    Email author
  • Tobias F. C. Berninger
    • 1
  • Daniel J. Rixen
    • 1
  1. 1.Faculty of Mechanical EngineeringTechnical University of MunichGarchingGermany

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