PRACTICAL APPLICATION OF MULTI-VARIABLE ROBUSTNESS METHODS TO ADVANCED AIRCRAFT FLIGHT CONTROL

MUCH OF THE MOTIVATIONS FOR RECENT DEVELOPMENTS IN GENERAL THEORY FOR ASSESSING ROBUSTNESS OF LINEAR MULTI-VARIABLE CONTROL SYSTEMS COMES FROM FLIGHT CONTROL SYSTEM DESIGN FOR AEROSPACE VEHICLES, WHICH PRESENT THE DESIGNER WITH MANY UNCERTAIN AND HIGHLY VARIABLE PROPERTIES. FOR THE ASSIMILATION OF THE NEW THEORIES INTO "REAL WORLD" DESIGN, FCS DESIGNERS WILL HAVE TO TRANSLATE THE THEORY INTO PHYSICAL UNDERSTANDING. THE PROPOSED WORK IS A DISTINCTLY DIFFERENT APPROACH TO BRIDGE THE GAP BETWEEN THE GENERAL THEORY AND COMPUTATIONAL METHODS OF LINEAR MULTI-VARIABLE ROBUSTNESS PROCEDURES, AND PHYSICAL UNDERSTANDING IN THE CONTEXT OF PRACTICAL FLIGHT CONTROL DESIGN. THE APPROACH ISBASED ON COMBINING SINGULAR VALUE AND STRUCTURED SINGULAR VALUE PROCEDURES WITH A LITERAL (SYMBOLIC) DEVELOPMENT WHICHLEADS TO DIRECT IDENTIFICATION OF IMPORTANT AIRCRAFT DYNAMICAND CONTROL SYSTEM DESIGN PARAMETERS AND THEIR CONNECTIONS WITH ROBUST PERFORMANCE CRITERIA. TO KEEP THE WORK FOCUSED ON PRACTICAL FLIGHT CONTROL PROBLEMS ILLUSTRATIVE EXAMPLES WILL CONSIDER REPRESENTATIVE FCS DESIGNS NEEDED TO COPE WITH VEHICLE DYNAMIC PROBLEMS EXPECTED TO BE ENCOUNTERED IN AIR-BREATHING HYPERSONIC AND HIGH ANGLE OF ATTACK SUPERMANEUVERABLE VEHICLES, INCLUDING THE DETERMINATION OF THE KEY UNCERTAINTIES ON WHICH THESE DESIGNS DEPEND.