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Multivariable Techniques for High-Speed Research Flight Control SystemsThis report describes the activities and findings conducted under contract with NASA Langley Research Center. Subject matter is the investigation of suitable multivariable flight control design methodologies and solutions for large, flexible high-speed vehicles. Specifically, methodologies are to address the inner control loops used for stabilization and augmentation of a highly coupled airframe system possibly involving rigid-body motion, structural vibrations, unsteady aerodynamics, and actuator dynamics. Design and analysis techniques considered in this body of work are both conventional-based and contemporary-based, and the vehicle of interest is the High-Speed Civil Transport (HSCT). Major findings include: (1) control architectures based on aft tail only are not well suited for highly flexible, high-speed vehicles, (2) theoretical underpinnings of the Wykes structural mode control logic is based on several assumptions concerning vehicle dynamic characteristics, and if not satisfied, the control logic can break down leading to mode destabilization, (3) two-loop control architectures that utilize small forward vanes with the aft tail provide highly attractive and feasible solutions to the longitudinal axis control challenges, and (4) closed-loop simulation sizing analyses indicate the baseline vane model utilized in this report is most likely oversized for normal loading conditions.
Document ID
20000012320
Acquisition Source
Langley Research Center
Document Type
Contractor Report (CR)
Authors
Newman, Brett A.
(Old Dominion Univ. Norfolk, VA United States)
Date Acquired
September 7, 2013
Publication Date
December 1, 1999
Subject Category
Aircraft Stability And Control
Report/Patent Number
NASA/CR-1999-209528
NAS 1.26:209528
Funding Number(s)
CONTRACT_GRANT: NAS1-19858
PROJECT: RTOP 537-07-24-23
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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