Date of Award
Master of Science in Electrical Engineering
Department of Electrical and Computer Engineering
The Electro-Hydrostatic Actuator (EllA) technology offers a higher degree of combat survivability and easier maintainability of the aircraft flight control system, because all the components necessary to operate the actuator are collocated with the actuator. Quantitative Feedback Theory (QFT) is used to design a control system for the EHA. The impact of parameter variations, sensor noise, and flight conditions are explicitly considered in the design process. The solution utilizes a two loop QFT feedback structure. The inner loop structure stabilizes the motor's angular velocity and decreases the outer loop's uncertainty. The outer loop structure controls the RAM piston's position to track the input command. The resulting design is not only robust with respect to plant parameter variations, but is also insensitive to the effects of sensor noise. The actuator's phase lag is reduced by incorporating phase constraints in the QFT design paradigm. QFT is shown to be a viable tool in solving a real-world problem.
DTIC Accession Number
Kang, Ki Ho, "Electro-Hydrostatic Actuator Controller Design Using Quantitative Feedback Theory" (1994). Theses and Dissertations. 6415.