Accession Number : ADA283700

Title :   Plant/Controller Optimization by Convex Methods.

Descriptive Note : Doctoral thesis,

Corporate Author : NAVAL POSTGRADUATE SCHOOL MONTEREY CA

Personal Author(s) : Niewoehner, Robert J., Jr

Report Date : JUN 1994

Pagination or Media Count : 283

Abstract : This report presents results of a three phase effort to demonstrate the use of convex control design techniques in aeronautical applications. The first phase was the demonstration of a methodology by which classical aircraft controller design requirements could be translated into the weighting matrices for H infinity controller synthesis. The second phase extended that methodology to the design of mixed H2 / H infinity controllers. The third phase considered the problem of minimizing the size of aircraft control surfaces while meeting closed-loop dynamic performance requirements. Control sizing is a critical element in the design of Reduced Static Stability (RSS) aircraft. Inadequate control power places the vehicle in peril, while too much control power forfeits the benefits of RSS, resulting in poorer performance, increased weight, increased cost, increased drag, and increased observability. Non-heuristic methods have been required by which the physical configuration and the accompanying controller can be designed directly from the flying qualities specifications. The optimization of the surfaces should be done while searching over the set of all controllers which, together in closed-loop, satisfy the flying qualities requirements. This report presents a methodology which simultaneously optimizes both the physical configuration and the control system of a rigid body, using performance requirements which can be posed as Linear Matrix Inequalities.

Descriptors :   *CONTROL SURFACES, *OPTIMIZATION, *AERONAUTICAL ENGINEERING, AIRCRAFT, BENEFITS, BODIES, CONFIGURATIONS, CONTROL SYSTEMS, COSTS, DEMONSTRATIONS, DRAG, DYNAMICS, HEURISTIC METHODS, INEQUALITIES, LOOPS, METHODOLOGY, PHASE, POWER, REQUIREMENTS, SEARCHING, SPECIFICATIONS, STABILITY, STATIC STABILITY, STATICS, SURFACES, SYNTHESIS, WEIGHT.

Subject Categories : Aerodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE