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Multi-application controls: Robust nonlinear multivariable aerospace controls applicationsThis viewgraph presentation describes the general methodology used to apply Honywell's Multi-Application Control (MACH) and the specific application to the F-18 High Angle-of-Attack Research Vehicle (HARV) including piloted simulation handling qualities evaluation. The general steps include insertion of modeling data for geometry and mass properties, aerodynamics, propulsion data and assumptions, requirements and specifications, e.g. definition of control variables, handling qualities, stability margins and statements for bandwidth, control power, priorities, position and rate limits. The specific steps include choice of independent variables for least squares fits to aerodynamic and propulsion data, modifications to the management of the controls with regard to integrator windup and actuation limiting and priorities, e.g. pitch priority over roll, and command limiting to prevent departures and/or undesirable inertial coupling or inability to recover to a stable trim condition. The HARV control problem is characterized by significant nonlinearities and multivariable interactions in the low speed, high angle-of-attack, high angular rate flight regime. Systematic approaches to the control of vehicle motions modeled with coupled nonlinear equations of motion have been developed. This paper will discuss the dynamic inversion approach which explicity accounts for nonlinearities in the control design. Multiple control effectors (including aerodynamic control surfaces and thrust vectoring control) and sensors are used to control the motions of the vehicles in several degrees-of-freedom. Several maneuvers will be used to illustrate performance of MACH in the high angle-of-attack flight regime. Analytical methods for assessing the robust performance of the multivariable control system in the presence of math modeling uncertainty, disturbances, and commands have reached a high level of maturity. The structured singular value (mu) frequency response methodology is presented as a method for analyzing robust performance and the mu-synthesis method will be presented as a method for synthesizing a robust control system. The paper concludes with the author's expectations regarding future applications of robust nonlinear multivariable controls.
Document ID
19950007835
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Enns, Dale F. (Honeywell, Inc. Minneapolis, MN., United States)
Bugajski, Daniel J. (Honeywell, Inc. Minneapolis, MN., United States)
Carter, John (NASA Hugh L. Dryden Flight Research Center Edwards, CA, United States)
Antoniewicz, Bob (NASA Hugh L. Dryden Flight Research Center Edwards, CA, United States)
Date Acquired
September 6, 2013
Publication Date
July 1, 1994
Publication Information
Publication: Fourth High Alpha Conference, Volume 2 26 p(SEE N95-14239 03-02)
Subject Category
Aerodynamics
Accession Number
95N14249
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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IDRelationTitle19950007815Collected WorksFourth High Alpha Conference: Volume 1
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