국내 최대 기계 및 로봇 연구정보

기술보고서

기술보고서 게시판 내용
타이틀	ON-LINE ROBUST MODAL STABILITY PREDICTION USING WAVELET PROCESSING
저자	Martin J. Brenner and Rick Lind
Keyword	Aeroservoelasticity; Modal estimation; Robust stability; Uncertainty modeling;
URL	http://www.dfrc.nasa.gov/DTRS/1998/PDF/H-2246.pdf
보고서번호	NASA-TM-1998-206550
발행년도	1998
출처	NASA Dryden Flight Research Center
ABSTRACT	Wavelet analysis for filtering and system identification has been used to improve the estimation of aeroservoelastic stability margins. The conservatism of the robust stability margins is reduced with parametric and nonparametric time-frequency analysis of flight data in the model validation process. Nonparametric wavelet processing of data is used to reduce the effects of external disturbances and unmodeled dynamics. Parametric estimates of modal stability are also extracted using the wavelet transform. Computation of robust stability margins for stability boundary prediction depends on uncertainty descriptions derived from the data for model validation. The F-18 High Alpha Research Vehicle aeroservoelastic flight test data demonstrates improved robust stability prediction by extension of the stability boundary beyond the flight regime. Guidelines and computation times are presented to show the efficiency and practical aspects of these procedures for on-line implementation. Feasibility of the method is shown for processing flight data from time-varying nonstationary test points.