Control Law Synthesis for Vertical Fin Buffeting Alleviation Using Strain ActuationIn the present investigation, the results obtained during the ground test of a closed-loop control system conducted on a full-scale fighter to attenuate vertical fin buffeting response using strain actuation are presented. Two groups of actuators consisting of piezoelectric elements distributed over the structure were designed to achieve authority over the first and second modes of the vertical fin. The control laws were synthesized using the Linear Quadratic Gaussian (LQG) method for a time-invariant control system. Three different pairs of sensors including strain gauges and accelerometers at different locations were used to close the feedback loop. The results demonstrated that measurable reductions in the root-mean-square (RMS) values of the fin dynamic response identified by the strain transducer at the critical point for fatigue at the root were achieved under the most severe buffet condition. For less severe buffet conditions, reductions of up to 58% were achieved.
Document ID
20040086830
Acquisition Source
Langley Research Center
Document Type
Other
Authors
Nitzsche, F. (National Research Council of Canada Ottawa, Ontario, Canada)
Zimcik, D. G. (National Research Council of Canada Ottawa, Ontario, Canada)
Ryall, T. G. (Defence Science and Technology Organisation Victoria, Australia)
Moses, R. W. (NASA Langley Research Center Hampton, VA, United States)
Henderson, D. A. (Air Force Research Lab. Wright-Patterson AFB, OH, United States)