
Accession Number : ADA273831
Title : Flight Controller Design Using Mixed H2/H Infinity Optimization with a singular H Infinity Constraint.
Descriptive Note : Master's thesis,
Corporate Author : AIR FORCE INST OF TECH WRIGHTPATTERSON AFB OH
Personal Author(s) : Luke, James P.
Report Date : DEC 1993
Pagination or Media Count : 135
Abstract : This thesis explores the effectiveness of mixed H2/H Infinity optimal control design applied to a realistic flight control problem. The application used by this thesis is a single input single output problem dealing with a normal acceleration command following model of the AFTI F16. The mixed H2/H Infinity control problem is broken into its component H2 and H Infinity parts; the H2 part is formulated as an LQG problem, and a weight is applied to system sensitivity in the H Infinity problem to obtain tracking performance. The sensitivity weight in the underlying H Infinity part results in a singular constraint on the mixed problem. A newlydeveloped numerical technique is applied and solutions are obtained for controllers of order equal to, first, the order of the underlying H2 problem and, second, the order of the underlying H Infinity problem. Performance characteristics of these controllers are compared to controllers designed using the moreconventional LQG/LTR design method. The results indicate the potential for controllers obtained through mixed H2/H Infinity optimization to provide excellent performance and robustness characteristics at orders less than those obtained through LQG/LTR. Since this conclusion grows in significance when applied to multiple input multiple output (MIMO) problems, a three input, five output example is introduced and the underlying H2 and H Infinity problems for two solution approaches are formulated. Mixed H2/H Infinity Optimization, H2 Optimization, H Infinity Optimization
Descriptors : *OPTIMIZATION, *SYSTEMS APPROACH, *FLIGHT CONTROL SYSTEMS, ACCELERATION, OUTPUT, SENSITIVITY, THESES, TRACKING, WEIGHT, AIRCRAFT NOISE, AIRCRAFT MODELS, INPUT.
Subject Categories : Flight Control and Instrumentation
Distribution Statement : APPROVED FOR PUBLIC RELEASE