Accession Number : ADA258841


Title :   Improvements to LQGI/LTR Methodology for Plants with Lightly Damped or Low Frequency Poles


Descriptive Note : Master's thesis


Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING


Personal Author(s) : Ju, An-Chi


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a258841.pdf


Report Date : Dec 1992


Pagination or Media Count : 134


Abstract : LQG/LTR design has a tendency to invert the plant's dynamics, which is undesirable if there are plant poles near the imaginary axis. In this study, Static Output Feedback (SOF) is applied to reassign plant poles before LQG/LTR is applied. Alternatively, Robust Eigenstructure Assignment (REA) was used to design the target loop transfer function with an ideal eigenstructure to avoid the undesirable cancellations. Both methods were applied to several aircraft design problems. Results showed that the methods can be effectively used so that the LQG/LTR design has improved stability and performance; however, it was found that each method had strengths and weaknesses.


Descriptors :   *RECOVERY , *TRANSFER , *CONTROL THEORY , *GAUSSIAN QUADRATURE , *LOOPS , OUTPUT , CONTROL , FUNCTIONS , AIRCRAFT , THESES , STATICS , PLANTING , AUTOMATIC FREQUENCY CONTROL , LOW FREQUENCIES , FEEDBACK , ALLOCATIONS , TARGETS , DYNAMICS , TRANSFER FUNCTIONS , METHODOLOGY , STABILITY


Subject Categories : Operations Research


Distribution Statement : APPROVED FOR PUBLIC RELEASE