VARIABLE STABILITY CONTROL ANALYSIS AND DESIGN FOR ICBM

A GENERAL METHODOLOGY IS PROPOSED FOR THE ANALYSIS AND SYNTHESIS OF ADVANCED CONTROL SYSTEMS FOR ICBM. THE EFFECT OF VARIABLE FLIGHT CONDITIONS ON THE STABILITY AND RESPONSE OF SUCH FLIGHT VEHICLES IS DISCUSSED. IN PARTICULAR, POSSIBILITIES OF COUNTERINTUITIVE BEHAVIOR SOMETIMES EXHIBITED BY SUCH SYSTEMS AND THE INADEQUACY AND MISREPRESENTATIONS OF USING SIMPLISTIC MODELS ARE DISCUSSED. IN CONTRAST TO THE USUAL PRACTICE OF USING BANDS OF FIXED GAINS IN THE CONTROL SYS TEMS, THE USE OF VARIABLE GAIN SCHEDULING IS ADDRESED IN ORDER TO IMPROVE SYSTEM PERFORMANCE. TO SOLVE THESE PROBLEMS, A SYSTEMATIC APPROACH TO THE ANALYSIS AND DESIGN OF NON-AUTONOMOUS CONTROL SYSTEMS FOR THESE VEHICLES WILL BE DEVELOPED. THE APPROACH TO BE USED IS THE GENERALIZED MULTIPLE SCALES (GMS) METHOD ESTABLISHED BY THE PRINCIPAL INVESTIGATOR. THIS METHOD IS IDEALLY SUITED TO THESE PROBLEMS AS IT IS PARTICULARLY APPLICABLE TO THE STUDY OF NON-AUTONOMOUS PHENOMENA EXHIBITING RAPID AND SLOW DYNAMICS AS IN THE CASE OF THE HYPERVELOCITY MISSILE. THE GMS APPROACH IS ESPECIALLY APPLICABLE TO THE DESIGN OF SUCH CONTROL SYSTEMS. THE PHASE I EFFORT WILL DEVELOP THE METHODOLOGY AND VALIDATE IT TO A FIRST LEVEL USING AVAILABLE ICBM DATA. THE PHASE II TASK WILL EXTEND AND REFINE THE TECHNIQUE TO TREAT MORE COMPLEX CHARACTERIZATIONS OF THE VEHICLE AND INCLUDE EXTENSIVE VALIDATION SIMULATIONS.