FACTORIZATION APPROACH

THE PROBLEM OF CONTROL DESIGN FOR LARGE SPACE STRUCTURES (LSS) IS VERY DEMANDING FOR SEVERAL REASONS: (1) THE TRUE DESCRIPTION OF THE FLEXIBLE MODES OF LSS IS INFINITE DIMENSIONAL, (2) STRUCTURAL DAMPING IS LOW, (3) TRACKING AND POINTING ACCURACY REQUIREMENTS ARE VERY HIGH, AND (4) COMPONENT FAILURES ARE TO BE TOLERATED BY THE CONTROL SYSTEM. THE USE OF CONTROL SYNTHESIS METHODS DEVELOPED PREVIOUSLY (BOTH CLASSICAL AND MODERN) HAS NOT BEEN VERY SUCCESSFUL DUE TO THE ABOVE DIFFICULTIES. PHASE I RESEARCH WILL INVESTIGATE A NEW PROMISING TECHNIQUE WHICH CAN SUCCESSFULLY ADDRESS ALL THE ABOVE PROBLEMS. THE CONTROL SYNTHESIS APPROACH IS BASED ON THE FACTORIZATION OF THE SYSTEM TRANSFER FUNCTION AND PRODUCES A FAMILY OF STABLE CONTROLLERS WHICH CAN ALL STABILIZE THE SYSTEM. THE PHASE I EFFORT WILL BE DEVOTED TO FURTHER DEVELOPMENTS OF THE THEORY AND NUMERICAL ALGORITHMS.