A Quantitative Performance Input for an Input Observer ( I ) - Analysis in Transient State -

입력관측기의 정량적 성능지표 (I) -과도상태 해석-

  • 정종철 (한양대학교 대학원 정밀기계공학과) ;
  • 이범석 (삼성테크원㈜) ;
  • 허건수 (한양대학교 기계공학부)
  • Published : 2002.10.01


The closed-loop state and input observer is a pole-placement type observer and estimates unknown state and input variables simultaneously. Pole-placement type observers may have poor transient performance with respect to ill-conditioning factors such as unknown initial estimates, round-off error, etc. For the robust transient performance, the effects of these ill-conditioning factors must be minimized in designing observers. In this paper, the transient performance of the closed-loop state and input observer is investigated quantitatively by considering the error bounds due to ill-conditioning factors. The performance indices are selected from these error bounds and are related to the observer robustness with respect to the ill -conditioning factors. The closed-loop state and input observer with small performance indices is considered as a well-conditioned observer from the transient perspective.


Performance Index;Transient State;Robustness;Closed-loop State and Input Observer(CSIO);Condition Number


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