Hostname: page-component-84b7d79bbc-rnpqb Total loading time: 0 Render date: 2024-07-27T21:29:49.689Z Has data issue: false hasContentIssue false

Helicopter load alleviation using active control

Published online by Cambridge University Press:  03 February 2016

M. Voskuijl
Affiliation:
Department of Engineering, The University of Liverpool, Liverpool, UK
D. J. Walker
Affiliation:
Department of Engineering, The University of Liverpool, Liverpool, UK
B. J. Manimala
Affiliation:
Department of Engineering, The University of Liverpool, Liverpool, UK

Abstract

This paper discusses how structural load objectives can be included in a rotorcraft flight control system design in an efficient and straightforward way using multivariable control techniques. Several research studies have indicated that pitch link loads for various rotorcraft types can reach high or even unacceptable values, both in steady state and maneuvering flight. This is especially the case for high-speed aggressive maneouvers. Pitch link loads at high-speed flight are therefore taken as a case study. A novel longitudinal control system is presented, designed to reduce helicopter pitch-link loads during high-speed longitudinal manoeuvres whilst providing a pitch attitude command attitude hold response type. The design is based on a high-order model of a helicopter representative of the UH-60 Black Hawk. New metrics are presented for the analysis of structural loads that can be used in combination with ADS-33 handling qualities requirements.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Prouty, R.W., Helicopter Aerodynamics – Ray Prouty’s Rotor and Wing Columns 1979-1992, 2004, Helobooks a division of Mojave books LLC, Mojave, CA, USA.Google Scholar
2. Loy, K., Carefree handling and its applications to military helicopters and missions, May 1997, American Helicopter Society’s 53rd annual forum, Virginia Beach, VA, USA.Google Scholar
3. Manimala, B.J., Walker, D.J., Padfield, G.D., Voskuijl, M. and Gubbels, A.W., Rotorcraft simulation modelling and validation for control law design, Aeronaut J, February 2007, 111, (1116), p 7788.CrossRefGoogle Scholar
4. Walker, D.J., Voskuijl, M., Manimala, B.J. and Gubbels, A.W., Nonlinear attitude control laws for the Bell 412 helicopter, AIAA J Guidance, Control and Dynamics, February-March 2008, 31, (1), p 4452.CrossRefGoogle Scholar
5. Padfield, G.D. and White, M.D., Flight simulation in academia – HELIFLIGHT in its first year of operation at the University of Liverpool, Aeronaut J, September 2003, 107, (1075), p 529538.CrossRefGoogle Scholar
6. Gubbels, A.W. and Carignan, S.J.R.P., The NRC Bell 412 Advanced Systems Research Aircraft — a new facility for airborne simulation, Canadian Aeronautics and Space J, June 2000, 46, (2), p 106115.Google Scholar
7. Baillie, S.W., Kereliuk, S., Murray Morgan, J. and Hui, K., An evaluation of the dynamics and handling quality characteristics of the Bell 412H helicopter, Canadian Aeronautics and Space J, March 1994, 40, (1), p 3246.Google Scholar
8. Curtiss, H. C., Carson, F., Hill, J., Quackenbush, T., Technical note – Performance of a Sikorsky S-61 with a new main rotor, J American Helicopter Soc, July 2003.CrossRefGoogle Scholar
9. Kufeld, R.M. and Bousman, W.G., High load conditions measured on a UH-60A in maneuvering flight, J American Helicopter Soc, July 1998, 43, (3), p 202211.CrossRefGoogle Scholar
10. Cresap, W.L., Myers, A.W. and Viswanathan, S.P., Design and development tests of a four-bladed light helicopter rotor system, May 1978, 34th annual forum of the American Helicopter Society.Google Scholar
11. Cresap, W.L. and Myers, A.W., Design and development of the model 412 helicopter, 36th annual forum of the American Helicopter Society, May 1980, Washington, DC, USA.Google Scholar
12. Yen, J.G. and Weller, W.H., Analysis and application of compliant rotor technology September 1980, Sixth European Rotorcraft and Powered Lift Aircraft Forum, Bristol, UK.Google Scholar
13. Bailey, F.J., A simplified theoretical method of determining the characteristics of a lifting rotor in forward flight, 1941, NACA report 716.Google Scholar
14. Mansur, M.H. and Tischler, M.B., An empirical correction for improving off-axis response in flight mechanics helicopter models, J American Helicopter Soc, 1998, 43, (2), p 94102.CrossRefGoogle Scholar
15. Kufeld, R.M. and Bousman, W.G., UH-60A helicopter rotor airloads measured in flight, Aeronaut J, May 1997, 101, (1005), p 217227.Google Scholar
16. Curtiss, H.C. and Carson, F., Further improvements to the S-61 helicopter, September 2005, 31st European Rotorcraft Forum, Florence, Italy.Google Scholar
17. Walker, D.J., Manimala, B.J., Voskuijl, M. and Gubbels, A.W., Multivariable control of the Bell 412 helicopter, 2006, Proceedings of the IEEE Conference on Decision and Control, No 4177255, p 15271535.CrossRefGoogle Scholar
18. Kwakernaak, H., Robust control and H-infinity optimization – tutorial paper, Automatica, 1993, 29, (2), p 255273.CrossRefGoogle Scholar
19. Manimala, B., Padfield, G.D., Walker, D., Naddei, M., Verde, L., Ciniglio, U., Rollet, P. and Sandri, F., Load alleviation in tilt rotor aircraft through active control: modelling and control concepts, Aeronaut J, April 2004, 108, (1082), p 169184.CrossRefGoogle Scholar
20. Padfield, G.D., Helicopter Flight Dynamics, 1996, Blackwell Science, Oxford, UK.Google Scholar
21. Coleman, R.P. and Feingold, A.M., Theory of self-excited mechanical oscillations of helicopter rotors with hinged blades, 1951, NACA 1351.Google Scholar
22. Gahinet, P., Nemirovski, A., Laub, A.J., and Chilali, M., LMI Control Toolbox, for use with MATLAB®, 1995, The Math Works, Natick, MA, USA.Google Scholar
23. Howlett, J.J., UH60A Black Hawk engineering simulation program: Volume I — Mathematical model, December 1981, NASA CR 166309.Google Scholar
24. Callister, W.D., Materials Science and Engineering an Introduction, 1997, John Wiley & Sons.Google Scholar
25. Gere, J.M. and Timoshenko, S.P., Mechanics of Materials, 1987, Chapman & Hall, London, UK.Google Scholar
26. Forth, S.C., Everett, R.A., Newman, J.A., A novel approach to rotor-craft damage tolerance, September 2002, Sixth Joint FAA/DoD/NASA aging aircraft conference, USA.Google Scholar
27. Miner, M.A., Cumulative damage in fatigue, ASME J Applied Mechanics, 1945, 12, p PA159164.CrossRefGoogle Scholar
28. Micheal, J., Collingwood, G., Augustine, M. and Cronkhite, J., Continued evaluation and spectrum development of a health and usage monitoring system, May 2004, DOT/FAA/AR-04/6, Fort Worth, TX, USA.Google Scholar
29. Anonymous. ADS-33E PRF, Aeronautical design standard performance specification, handling qualities requirements for military rotorcraft.Google Scholar
30. Martyn, A.W., Charlton, M.T. and Padfield, G.D., Vehicle structural fatigue issues in rotorcraft flying qualities testing, September 1995, 21st European Rotorcraft Forum, St Petersburg, Russia.Google Scholar
31. Anonymous. Monitor limits for MoD flight trials, 3 February 1994, WHL, SDR 84, 3.Google Scholar
32. Pavel, M.D. and Padfield, G.D., Defining consistent ADS-33 metrics for agility enhancement and structural loads alleviation, June 2002, 58th Annual Forum of the American Helicopter Society, Montreal, Canada.Google Scholar