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Parameter Estimation for Randomly Excited Non-Linear Systems

A Method based on Moment Equations and Measured Response
  • J. B. Roberts
  • J. F. Dunne
  • A. Debonos
Part of the Solid Mechanics and its Applications book series (SMIA, volume 47)

Abstract

The problem of estimating unknown parameters in a non-linear randomly excited dynamic system, when the excitation is unmeasurable, is considered. It is shown that, if the excitation is modelled stochastically as a Gaussian process, with a prescribed spectral form, it is possible to estimate the parameters from response data alone using either moment equations or a spectral input-output relationship. When applied to simulated data for a particular non-linear oscillator, as an example, it is found that the use of moment equations leads to a very good estimation of the stiffness parameters but is incapable of yielding estimates of the absolute level of damping. However the latter can be found accurately by applying a spectral relationship. Improvements in the accuracy of estimation for the damping parameters, and the input intensity, are achieved by using a theoretical expression for the distribution of the energy envelope of the response in combination with statistical linearisation.

Keywords

Moment Equation Stiffness Parameter Sample Function Stochastic Average Ship Roll 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Kluwer Academic Publishers 1996

Authors and Affiliations

  • J. B. Roberts
    • 1
  • J. F. Dunne
    • 1
  • A. Debonos
    • 1
  1. 1.School of Engineering, University of SussexFalmerUK

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