Accession Number : ADA211957


Title :   Robust Control Design for Flight Control


Descriptive Note : Final rept. Jul 1988-Mar 1989


Corporate Author : TECHNO-SCIENCES INC GREENBELT MD


Personal Author(s) : Bennett, William H. ; Kwatny, Harold G. ; Glover, Keith


Report Date : JUL 1989


Pagination or Media Count : 92


Abstract : This project studies the application of new and advanced methods of control law synthesis for robust stabilization with respect to a combination of both unstructured model uncertainty (arising from neglected parasitic dynamics) and structured model uncertainty (arising from parametric variations which occur as flight conditions change). Efforts have focused on the characterization of a class of nonlinear models for longitudinal dynamics of aircraft in level flight subject to changes in static stability. Such 'relaxed stability' aircraft configurations are currently at issue in a wide variety of advanced designs including commercial transport and high performance aircraft. The control design approach employs H-infinity synthesis methods for optimal robust stabilization for the unstructured model uncertainty, and the requirement of worst case (i.e., robust) design for parametric uncertainty is included using a minimax optimization criteria. This study has focused on a class of flight control models with physically based parametric uncertainty. For these models, the solution of the minimax or worst case design is achieved by a straightforward procedure which can be readily combined with the requirements for robustness to parasitic dynamics using the closed form solution of the optical robust stabilization method.


Descriptors :   *FLIGHT CONTROL SYSTEMS , STATIC STABILITY , CONTROL , STABILITY , HIGH RATE , AIRCRAFT , COMMERCIAL AIRCRAFT , MODELS , SYNTHESIS , PERFORMANCE(ENGINEERING) , DYNAMICS , PARAMETERS , VARIATIONS , NONLINEAR SYSTEMS , CONFIGURATIONS , CONTROL THEORY , LEVEL FLIGHT , TRANSPORT AIRCRAFT , STABILIZATION , MATHEMATICAL MODELS


Subject Categories : FLIGHT CONTROL AND INSTRUMENTATION


Distribution Statement : APPROVED FOR PUBLIC RELEASE