ROBUST NONLINEAR CONTROL DESIGNS FOR COMPLEX DYNAMIC SYSTEM

THE NONLINEARITIES AND UNCERTAINTIES INHERENT IN COMPLEX DYNAMIC SYSTEMS, SUCH AS THE DEVELOPMENT OF AUTOPILOT SYSTEMS FOR AIRCRAFT, IMPOSE GREAT CHALLENGES TO LINEAR CONTROL SYSTEMS DESIGN. SEVERAL ADVANCED ROBUST NONLINEAR APPROACHES, NAMELY, NONLINEAR H-INFINITY, INVERSION-BASED CONTROL LAWS, ANALYTICAL GAIN SCHEDULING, AND NONLINEAR SERVOMECHANISM DESIGN ARE BEING USED TO DESIGN A HIGH PERFORMANCE AUTOPILOT. THE UNIQUE FEATURES OF THESE APPROACHES INCLUDE INCORPORATION OF NONLINEAR DYNAMICS INTO THE DESIGN PROCESS; PROVISION FOR ROBUST SCHEMES TO ACCOUNT FOR MODEL UNCERTAINTIES; AND UTILIZATION OF ADAPTIVE MECHANISMS TO HANDLE PARAMETER VARIATIONS. THESE FEATURES SYNERGISTICALLY YIELD A CONTROL SYSTEM WITH A LARGER OPERATION RANGE, INCREASED ROBUSTNESS TO PARAMETRIC VARIATIONS, FASTER RESPONSE SPEED, AND MORE ACCURATE TRACKING CAPABILITIES, THEREBY ENHANCING THE OVERALL SYSTEM PERFORMANCE. THE DELIVERABLES INCLUDE A COMPREHENSIVE NONLINEAR DESIGN/ANALYSIS TOOL TOGETHER WITH DETAILED DOCUMENTATION.