A FREQUENCY DOMAIN METHOD FOR ESTIMATING THE PARAMETERS OF A NON-LINEAR STRUCTURAL DYNAMIC MODEL THROUGH FEEDBACK

✍ Scribed by D.E. ADAMS; R.J. ALLEMANG

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 250 KB
• Volume: 14
• Category: Article
• ISSN: 0888-3270
• DOI: 10.1006/mssp.2000.1292

✦ Synopsis

A unifying perspective of non-linear structural dynamic systems as linear in the open loop with non-linear feedback in the closed loop has recently been revisited by the authors. The authors have previously used feedback to derive a new formulation of frequency response function matrices of non-linear systems, which are described as modulations of nominal linear systems. The modulation creates a pseudo-separation of the linear and non-linear dynamics of the system. The present article derives a new method for estimating parameters of non-linear parametric models that uses internal feedback to account for non-linearities. The main advantage of the new formulation of non-linear system identi"cation is its simplicity. Moreover, the method estimates the linear frequency response matrix and non-linear system parameters at forced and unforced degrees of freedom of general multipledegree-of-freedom non-linear systems simultaneously. This article demonstrates the implementation of this method on simulated data from single-and multiple-degree-of-freedom lumped parameter models.