Modal Reduction Based on Accurate Input-Output Relation Preservation

  • M. Khorsand VakilzadehEmail author
  • S. Rahrovani
  • T. Abrahamsson
Conference paper
Part of the Conference Proceedings of the Society for Experimental Mechanics Series book series (CPSEMS)


An eigenmode based model reduction technique is proposed to obtain low-order models which contain the dominant eigenvalue subspace of the full system. A frequency-limited interval dominancy is introduced to this technique to measure the output deviation caused by deflation of eigenvalues from the original system in the frequency range of interest. Thus, the dominant eigensolutions with effective contribution can be identified and retained in the reduced-order model. This metric is an explicit formula in terms of the corresponding eigensolution. Hence, the reduction can be made at a low computational cost. In addition, the retained low-order model does not contain any uncontrollable and unobservable eigensolutions. The performance of the created reduced-order models, in regard to the approximation error, is examined by applying three different input signals; unit-impulse, unit-step and linear chirp.


Modal analysis Frequency-limited dominancy metric Unit-impulse response Model reduction Linear system dynamics 


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Copyright information

© The Society for Experimental Mechanics 2014

Authors and Affiliations

  • M. Khorsand Vakilzadeh
    • 1
    Email author
  • S. Rahrovani
    • 1
  • T. Abrahamsson
    • 1
  1. 1.Department of Applied MechanicsChalmers University of TechnologyGothenburgSweden

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