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Active Control of a hybrid actuation system for aircraft vertical fin buffet load alleviation

Published online by Cambridge University Press:  03 February 2016

Y. Chen
Affiliation:
Institute for Aerospace Research, National Research Council of Canada Ottawa, Canada
V. Wickramasinghe
Affiliation:
Institute for Aerospace Research, National Research Council of Canada Ottawa, Canada
D. Zimcik
Affiliation:
Institute for Aerospace Research, National Research Council of Canada Ottawa, Canada

Abstract

Twin-tail fighter aircraft may experience intense buffet loads when flying at high angles of attack. One such aircraft is the F/A-18 where the broadband buffet loads primarily excite the first bending and torsional modes of the vertical fin, resulting in significant vibration and dynamic stresses on the vertical tail structure. This buffet phenomenon reduces the fatigue life of the aircraft structure while decreasing mission availability.

An international technical co-operation program was initiated to develop a novel hybrid actuation system to actively alleviate the buffet response of a full-scale F/A-18 vertical fin. A hydraulic rudder actuator was used to control the bending mode of the vertical fin using rudder inertia forces. Multiple macro fiber composite actuators were distributed optimally to provide maximum induced strain control authority for the torsional mode. In order to develop an effective control law, a system identification approach was conducted to obtain a state-space model of the vertical fin using open-loop test data. An LQG control law was selected to minimise the dynamic response of the vertical fin at critical locations. The effectiveness of the control law was verified through extensive simulation prior to closed-loop experiments. The LQG control law demonstrated high robustness in all excitation load conditions; both bending and torsional vibration modes of the vertical tail were suppressed effectively and simultaneously. The dynamic stress and acceleration response at critical locations were also reduced significantly. A closed-loop experiment was conducted on a full-scale F/A-18 empennage using the IFOSTP test rig, and the experimental results verified the effectiveness of the control law development methodology used for the full-scale hybrid buffet load system for the F/A-18 aircraft. In addition, the ground vibration test demonstrated that the hybrid actuation system is a feasible solution to alleviate the vertical tail buffet loads in high performance fighter aircraft.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2006 

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References

1. Hauch, R.M., Jacobs, J.H., Dima, C. and Ravindra, K. Reduction of vertical tail buffet response using active control, J Aircr, 1996, 33, (3), pp 617622.Google Scholar
2. Wickramasinghe, V., Chen, Y. and Zimcik, D. Canadian contribution to the international buffet load alleviation program for F/A-18 vertical tail, CANSMART 2005: International Workshop on Smart Materials and Structures, Toronto, Canada, 13–14 October 2005.Google Scholar
3. Sheta, E.F. Buffet Alleviation of F/A-18 aircraft using LEX fences, 44th AIAA/ASME/ASCE/AHS Structures, Structural Dynamics, and Materials Conference, Norfolk, Virginia, USA, 7–10 April 2003.Google Scholar
4. Nitzsche, F., Liberatore, S. and Zimcik, D. G., Theoretical and experimental investigations on an active control system for vertical fin buffeting alleviation using strain actuation, Aeronaut J, 2001, 105 (1047), pp 277285.Google Scholar
5. Ferman, M.A., Liguore, S.L., Colvin, B.J. and Smith, C.M. Composite exoskin doubler extends F-15 vertical tail fatigue life, 34th AIAA Structures, Structural Dynamics, and Materials Conference, Lajolla, California, USA, 19–22 April 1993.Google Scholar
6. Burnham, J.K., Pitt, D.M., White, E.V., Henderson, D.A. and Moses, R.W. An advanced buffet load alleviation system, 42nd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, Seattle, Washington, USA. AIAA2001-1666, 16–19 April 2001.Google Scholar
7. Moses, R.W. NASA Langley Research Center’s contributions to the international active buffeting alleviation programs, NATO-RTO Workshop on Structural Aspects of Flexible Aircraft Control, Ottawa, Canada, 18–21 October 1999.Google Scholar
8. Moses, R.W., Wieseman, C.D., Bent, A.A. and Pizzochero, A.E. Evaluation of new actuators in a buffet loads environment, Smart Structures and Materials 2001: Industrial and Commercial Applications on Smart Structures Technologies, Proceedings of SPIE 4332(2001), Newport Beach, CA, USA, 5–8 March 2001.Google Scholar
9. Hanagud, S., de Noyer, M.B., Luo, H., Henderson, D. and Nagaraja, K. S. Tail buffet alleviation of high performance twin-tail aircraft using piezostack actuators, AIAA J, 2002, 40, (4), pp 619627.Google Scholar
10. Ei-Badaway, A.A. and Nayfeh, Al. Buffet alleviation of twin-tail fighter aircraft using saturation-based control, Proceedings of the international modal analysis conference (IMAC19), Kissimmee, FL, USA February 2001, pp 928934.Google Scholar
11. Hopkins, M., Henderson, D., Moses, R.W., Ryall, T., Zimcik, D.G. and Spangler, R. Active vibration suppression systems applied to twin tail buffeting, Smart structures and materials 1998: Industrial and commercial applications of smart structures technologies; SPIE 332(1998), San Diego, CA, USA, 3–5 March 1998.Google Scholar
12. Nitzsche, F., Zimcik, D.G., Ryall, T.G., Moses, R.W. and Henderson, D.A. Closed-loop control test for vertical fin buffeting alleviation using strain actuation, J Guidance, Control, and Dynamics, 2001, 24, (4), pp 855857.Google Scholar
13. Burnham, J.K., Pitt, D.M., White, E.V., Hendreson, D.A. and Moses, R.W. An advanced buffet load alleviation system, AIAA-2001-1666.Google Scholar
14. Galea, S.C., Henderson, D.A., Moses, R.W., Zimcik, D.G., White, E.V. and Ryall, T.G. Next generation active buffet suppression system, 2003 AIAA/ICAS International Air and Space Symposium and Exposition: The Next 100 Years, Dayton, OH, USA, 14–17 July 2003.Google Scholar
15. Conser, D.P., Graham, A.D., Smith, C.J. and Yule, C.L. The application of dynamic loads to a full scale F/A-18 fatigue test article, ICAS-96-5.10.5, 20th Congress of the International Council of Aeronautical Sciences, 8–13 September 1996, Sorrento, Napoli, Italy.Google Scholar
16. Moses, R.W., Pototzky, A.S., Henderson, D.A., Galea, S.C., Manokran, D.S., Zimcik, D.G. and Wickramasinghe, V.K. Actively controlling buffet-induced excitations, RTO-MP-AVT-123.Google Scholar