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An improved method for parameter selection in finite element model updating

Published online by Cambridge University Press:  04 July 2016

M. J. Ratcliffe  and
N. A. J. Lieven
M. J. Ratcliffe
Affiliation:
Department of Aerospace EngineeringUniversity of BristolBristol, UK
N. A. J. Lieven
Affiliation:
Department of Aerospace EngineeringUniversity of BristolBristol, UK
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Abstract

Conventional wisdom states that coordinate complete experimental response data are required to effect a successful model update. This paper examines the influence measured rotational degrees of freedom have on the behaviour of the frequency response function (FRF) sensitivity updating procedure. Three finite element (FE) model-based case studies are undertaken which suggest that very little improvement is afforded by the inclusion of measured rotations in the updating process.

Error-location strategies in the past have yielded little qualitative information about the optimum selection of updating parameters in the model updating procedure. Two further cases are investigated; these suggest that no amount of coordinate completeness will rectify the debilitating effects of an inadequate p-value choice. A method of selecting the number and location of updating parameters — based on the FRF sensitivity method — is presented. This method is shown to yield promising results.

Type
Research Article
Information
The Aeronautical Journal , Volume 102 , Issue 1016 , July 1998 , pp. 321 - 329
Copyright
Copyright © Royal Aeronautical Society 1998 

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