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Life extending control of aircraft: trade-off between flight performance and structural durability

Published online by Cambridge University Press:  04 July 2016

A. Ray
Affiliation:
Pennsylvania State University, USA
J. Caplin
Affiliation:
Pennsylvania State University, USA

Abstract

The goal of life extending control (LEC) is to enhance the service life of complex mechanical systems, such as aircraft, spacecraft, and energy conversion devices, without any significant loss of performance, and can be achieved by making a trade-off between dynamic performance and structural durability. This paper presents the concept and a design methodology for robust life extending control of aircraft structures that are typically subjected to cyclic mechanical stresses. The controller design procedure relies on the specifications of flight performance and allowable fatigue crack damage at critical points of aircraft structures that serve as indicators of the effective service life. As an example, an aeroelastic model of the aircraft wings has been formulated and is incorporated into a nonlinear rigid-body model of the flight-dynamics. The H∞-based structured singular value (μ) synthesis method has been used to design robust life extending controllers based on a linearised model of the aircraft and a (nonlinear) state-space model of fatigue crack growth. The results of simulation experiments show significant savings in fatigue life of the wings while retaining the dynamic performance of the aircraft.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 1979 

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References

1. Matsuzaki, Y., Ueda, T., Miyazawa, Y. and Matsushita, H. Gust load alleviation of a transport-type wing: test and analysis, J Airc, 1989, 26, (4), pp 322327.Google Scholar
2. Baldelli, D.H, Ohta, H. and Nitta, K. Gust load alleviation of an aeroelastic wing model, Transactions of the Japanese Society for Aeronautical and Space Sciences, 1993, 36, (113), pp 125142.Google Scholar
3. McLean, D., Automatic Flight Control Systems, 1990, Prentice Hall International, London.Google Scholar
4. Thornton, S.V. Reduction of structural loads using manoeuvre load control on the advanced fighter technology integration (AFTI)/F-111 mission adaptive wing, NASA TM-4526, 1993.Google Scholar
5. Anderson, T.L. Fracture Mechanics, Fundamentals and Applications, 1995, 2nd ed, CRC Press, Boca Raton.Google Scholar
6. Patankar, R. and Ray, A. State-space modelling of fatigue crack growth in ductile alloys, engineering fracture mechanics, 2000, 66, pp 129151.Google Scholar
7. Ray, A., Wu, M-K., Carpino, M. and Lorenzo, C.F. Damage-mitigating control of mechanical systems: Parts I and II, ASME J of Dynamic Systems, Measurement and Control, 1994, 116, (3), pp 437455.Google Scholar
8. Dai, X. and Ray, A. Damage-mitigating control of a reusable rocket engine: Parts I and II, ASME J Dynamic Systems, Measurement and Control, 118, (3), pp 401415.Google Scholar
9. Holmes, M. and Ray, A. Fuzzy damage mitigating control of mechanical structures, ASME J Dynamic Systems, Measurement and Control, 1998, 120, (2), pp 249256.Google Scholar
10. Rozak, J.H. and Ray, A. Robust multivariable control of rotorcraft in forward flight, J Amer Heli Soc, 1997, 42, (2), pp 149160.Google Scholar
11. Kallappa, P.T., Holmes, M. and Ray, A. Life extending control of fossil power plants for structural durability and high performance, Automatica, 1997, 33, (6), pp 11011118.Google Scholar
12. Kallappa, P.T. and Ray, A. Fuzzy wide range control of fossil power plants for life extension and robust performance, Automatica, 2000, 36, (1), pp 6982.Google Scholar
13. Zhang, H. and Ray, A. Robust damage damage-mitigating control of mechanical structures: experimental validation on a test apparatus, ASME J Dynamic Systems, Measurement and Control, 1999, 121, (3), pp 377385.Google Scholar
14. Buffington, J.M., Sparks, A.G. and Banda, S.S. Robust longitudinal axis flight control for an aircraft with thrust vectoring, Automatica, 1994, 30, (10), pp 15271540.Google Scholar
15. Durham, W.C. Constrained control allocation, Proceedings of the 1992 AIAA Guidance, Navigation, and Control Conference, 1992, pp 11471155.Google Scholar
16. Rozak, J.H. and Ray, A. Robust multivariable control of rotorcraft in forward flight: impact of bandwidth on fatigue life, J Amer Heli Soc, 1998, 43, (3), pp 195201.Google Scholar
17. Brumbaugh, R.W. An aircraft model for the AIAA controls design challenge, AIAA Paper 91-2631, 1991.Google Scholar
18. Adams, J.R., Buffington, J.M., Sparks, A.G. and Banda, S.S. Robust Multivariable Flight Control, 1994, Springer-Verlag, London.Google Scholar
19. DoD, 1980, Military Specifications — Flying Qualities of Piloted Airplanes, MIL-F-8785C, Department of Defense, Washington, DC.Google Scholar
20. US Standard Atmosphere, 1962, US Government Printing Office, Washington, DC.Google Scholar
21. Etkin, B. Dynamics of Atmospheric Flight, 1972, John Wiley & Sons, New York.Google Scholar
22. Caplin, J. Damage-mitigating control of aircraft for high performance and life extension, Doctoral Dissertation in Mechanical Engineering, 1998, Pennsylvania State University, University Park, PA.Google Scholar
23. Dowell, E.H. (Ed), Crawley, E.F., Curtiss, H.C., Peters, D.A., Scanlan, R.H. and Slsto, F. A Modern Course in Aeroelasticity, 3rd Ed, 1995, Kluwer Press, Dordrecht, The Netherlands.Google Scholar
24. Albano, E. and Rodden, W.P. A doublet-lattice method for calculating lift distributions on oscillating surfaces in subsonic flows, AIAA J, 1969, 7, (2), pp 279285; also Errata, 7, (11), pp 2,192.Google Scholar
25. Karpel, M. Time-domain aeroservoelastic modelling using weighted unsteady aerodynamic forces, J Guidance, Control, and Dynamics, 1990, 13, (l), pp 3037.Google Scholar
26. Schijve, J. Observations on the prediction of fatigue crack growth propagation under variable-amplitude loading, fatigue crack growth under spectrum loads, ASTM STP 595, 1976, pp 323.Google Scholar
27. McMillan, J. C. and Pelloux, R.M.N. Fatigue crack propagation under program and random loads, fatigue crack propagation, ASTM STP 415, 1967, pp 505532 (Also BSRL Document D1-82-0558, 1966).Google Scholar
28. Porter, T.R. Method of analysis and prediction for variable amplitude fatigue crack growth, Eng Fracture Mechanics, 1972, 4, pp 717736.Google Scholar
29. Suresh, S. Fatigue of Materials, 1991, Cambridge University Press, Cambridge, UK.Google Scholar
30. Newman, J.C. A crack-closure model for predicting fatigue crack growth under aircraft loading, methods and models for predicting fatigue crack growth under random loading, ASTM STP 748, 1981, pp 5384.Google Scholar
31. Newman, J.C. FASTRAN-II — A fatigue crack growth structural analysis program, NASA Technical Memorandum 104159, 1992, Langley Research Centre, Hampton, VA.Google Scholar
32. Newman, J.C. A crack opening stress equation for fatigue crack growth, Int J of Fracture, 1984, 24, pp R131R135.Google Scholar
33. Ibrahim, F. K., Thompson, J. C. and Topper, T. H. A study of effect of mechanical variables on fatigue crack closure and propagation, Int J of Fatigue, 1986, 8, (3), pp 135142.Google Scholar
34. Lorenzo, C.F., Holmes, M. and Ray, A. Nonlinear life extending control of a rocket engine, AIAA J of Guidance, Control, and Dynamics, 23, (4), pp 759762.Google Scholar
35. Zhou, K., Doyle, J.C. and Glover, K. Robust and Optimal Control. 1996, Prentice-Hall, NJ.Google Scholar
36. Balas, G.J., Doyle, J.C, Glover, K., Packard, A. and Smith, R. μ-Analysis and Synthesis Toolbox, 1993, MUSYN and The Math Works.Google Scholar
37. Bamieh, B.A. and Pearson, J.B. A general framework for linear periodic systems with applications to H∞-sampled data control, IEEE Trans on Automatic Control, 1992, 37, (4), pp 418435.Google Scholar
38. Shivashankar, N. and Khargonekar, P.P. Robust stability and performance analysis of sampled-data systems, IEEE Trans on Automatic Control, 1993, 38, (1), pp 5869.Google Scholar
39. Patankar, R. and Ray, A. Damage mitigating controller design for structural durability, IEEE Trans on Control Systems Technology, 1999, 7, (5), pp 606612.Google Scholar
40. Zhang, H., Ray, A. and Patankar, R. Damage-mitigating control with overload injection: experimental validation of the concept, ASME J Dynamic Systems, Measurement, and Control, 2000, 122, (2), pp 336342.Google Scholar