Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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On the Number of Modes Required to Observe Forces in Flexible Structures

유연 구조물에서 반력 평가를 위해 요구되는 모드의 수

  • Kim, Joo-Hyung (Graduate School of Autimotive Engineering, Kookmin University) ;
  • Kim, Sang-Sup (Graduate School of Autimotive Engineering, Kookmin University)
  • 김주형 (국민대학교 자동차전문 대학원) ;
  • 김상섭 (국민대학교 자동차전문 대학원)
  • Published : 2002.01.01
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Abstract

The number of required modes to provide accurate force information in a truncated model of a flexible structure is investigated. In the case of modal truncation of a distributed parameter system, the difference in convergence rates between displacements and forces is discussed. The residual flexibility. a term from past literature, is used to recapture some of the lost force information in a truncated model. This paper presents numerical and experimental results of a study where the residual flexibility is used in conjunction with a Kalman filter so that accurate force information may be obtained from a small set of displacement measurements wish a reduced-order model. The motivation for this paper is to be able to obtain accurate information about unmeasurable dynamic reaction forces in a rotating machine for diagnostic and control purposes.

Keywords

References

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