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Active control to augment rotor lead-lag damping

Published online by Cambridge University Press:  04 July 2016

C. Kessler and
G. Reichert
C. Kessler
Affiliation:
Institute of Flight Mechanics Technical , University of Braunschweig Germany
G. Reichert
Affiliation:
Institute of Flight Mechanics Technical , University of Braunschweig GermanyWe regret to announce that Professor Reichert died on 7 March 1997
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Abstract

Hingeless and bearingless rotor designs are today well accepted for modern helicopters. Continued development, however, revealed some deficiencies in the area of aeromechanical stability and vibration. In general there is a good basic understanding of how to avoid these instabilities. But since it becomes more and more desirable to focus rotor design on aerodynamic features and flight performance, these aeromechanical instabilities gain new importance due to the difficulties to provide the required damping.

Since all rotor concepts suffer from the lack of sufficient natural lead-lag or inplane damping most designs in use show artificial lead-lag dampers to overcome aeromechanical instabilities. Additionally, active control offers the possibility for an artificial stabilisation of aeromechanical instabilities. Meanwhile, many research activities focus on active control to augment rotor lead-lag damping and many authors demonstrate the potential inherent in this approach.

Information

Type
Research Article
Information
The Aeronautical Journal , Volume 102 , Issue 1015 , May 1998, pp. 245 - 258
Copyright
Copyright © Royal Aeronautical Society 1998 

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References

1. Reichert, G. and Huber, H. Influence of elastic coupling effects on the handling qualities of a hingeless rotor helicopter, AGARD CP-121, February 1973, pp 8.1–8.1.Google Scholar
2. Huber, H. Effect of torsion-flap-lag coupling on hingeless rotor stability, 29th Annual National Forum of the American Helicopter Society, May 1973, pp 1–14.Google Scholar
3. Hansford, R.E. and Simons, LA. Torsion-flap-lag coupling on helicopter rotor blades, J Amer Heli Soc, October 1973,18, (4), pp 2–12.Google Scholar
4. Donham, R.E. Cardinale, S.V. and Sachs, IB. Ground and air resonance characteristics of a soft in-plane rigid-rotor system, J Amer Heli Soc, October 1969,14, (4), pp 33–41.Google Scholar
5. Ormiston, R.A. Aeromechanical stability of soft inplane hingeless rotor helicopters. 3rd European Rotorcraft Forum, Aix-En-Provence, France, September 7-9 1977, pp 25.1–25.2.1.Google Scholar
6. Lytwyn, R.T., Miao, W. and Woitsch, W. Airborne and ground reso nance of hingeless rotors, J Amer Heli Soc, April 1971, 16, (2), pp 2–9.Google Scholar
7. Kessler, CH. and Reichert, .G. Active control of ground and air resonance including transition from ground to air, 20th European Rotorcraft Forum, Amsterdam, Netherlands, October 4-7 1994, pp 64.1–64.17.Google Scholar
8. Peters, D.A. Flap-lag stability of helicopter rotor blades in forward flight, JAmer Heli Soc, 1975, 20, (4), pp 1–13.Google Scholar
9. Panda, B. and Chopra, I. Flap-lag-torsion stability in forward flight,J Amer Heli Soc, October 1985, 30, (4), pp 30–39.Google Scholar
10. Hodges, D.H. and Ormiston, R.A. Stability of elastic bending and torsion of uniform cantilever rotor blades in hover with variable structural coupling, NASA TN D-8192, April 1976.Google Scholar
11. Ormiston, R.A., Warmbrodt, W.G., Hodges, D.H. and Peters, D.A. Rotorcraft aeroelastic stability, NASA CP-2495, pp 353–529, 1988.Google Scholar
12. Reichert, G. Active control of helicopter ground and air resonance, 3rd Technical Workshop: Dynamics and Aeroelastic Stability Modeling of Rotorcraft Systems, Duke University, Durham, North Carolina, March 12-14 1990.Google Scholar
13. Young, M.I., Bailey, D.J. and Hirschbein, M.S. Open and closed loop stability of hingeless rotor helicopter air and ground resonance. AHS/NASA-Ames Specialists’ Meeting on Rotorcraft Dynamics, pp 1–32, February 13-15 1974.Google Scholar
14. Straub, F.K. and Warmbrodt, W. The use of active controls to augment rotor/fuselage stability, J Amer Heli Soc, July 1985, 30, (3), pp 13–22.Google Scholar
15. Straub, F.K. Optimal control of helicopter aeromechanical stability, 11th European Rotorcraft Forum, London, England, 10-13 September 1985, pp 77.1–77.16.Google Scholar
16. Takahashi, M.D. and Friedmann, P.P. A model for active control of helicopter air resonance in hover and forward flight, 14th European Rotor craft Forum, Milano, Italy, 20-23 September 1988, pp 57.1–57.23.Google Scholar
17. Kube, R., Wall, B.V.D. and Schultz, K.-J. Mechanisms of vibration and BVI noise reduction by Higher Harmonic Control, 20th European Rotorcraft Forum, Amsterdam, Netherlands, 4-7 October 1994, pp 27.1–27.23.Google Scholar
18. Richter, P. and Schreiber, T. Theoretical Investigations and windtunnel tests with HHC-IBC, 20th European Rotorcraft Forum, Amsterdam, Netherlands, 4-7 October 1994, pp 71.1–71.15.Google Scholar
19. Ham, N.D. Helicopter Individual Blade Control and its applications, 9th European Rotorcraft Forum, Stresa, Italy, 13-15 September 1983, pp 56.1–56.11.Google Scholar
20. Ham, N.D. A simple system for helicopter Individual Blade Control using modal decomposition, Vertica, 1980, 4, (1), pp 23–28.Google Scholar
21. Ham, N.D. Helicopter Individual Blade Control research at MIT 1977-1985, Vertica, 1987,11, (1/2), pp 109–122.Google Scholar
22. Ham, N.D. and Quackenbush, T.R. A simple system for helicopter indi vidual-blade-control and its application to stall flutter suppression, 7th European Rotorcraft Forum, Garmisch-Partenkirchen, Germany, 8-11 September 1981, pp 76.1–76.28.Google Scholar
23. Ham, N.D. Helicopter gust alleviation, attitude stabilisation, and vibration alleviation using individual-blade-control through a conventional swash plate, 11th European Rotorcraft Forum, London, England, 10-13 September 1985, pp 75.1–75.5.Google Scholar
24. Ham, N.D., Behal, B.L. and Mckillip, R.M. Helicopter rotor lag, damping augmentation through individual-blade-control, Vertica, 1983, 7, (4), pp 361–371.Google Scholar
25. Teves, D., Kloppel, V. and Richter, P. Development of active control technology in the rotating system, flight testing and theoretical investigation, 19th European Rotorcraft Forum, Avignon, France, 15-18 September 1992, pp 89.1–89.13. Google Scholar
26. Richter, P. and Blaas, P.A. Full sacle windtunnel investigation of an individual blade control system for Bo 105 hingeless rotor, 19th European Rotorcraft Forum, Cernobbio (Como), Italy, 14-16 September 1990, ppG5.1-G5.12.Google Scholar
27. Reichert, G. and Arnold, U. Active control of helicopter ground and air resonance, 16th European Rotorcraft Forum, Glasgow, Scotland, 18-20 September 1990, pp 111.6.2,1–111.6.2.14.Google Scholar
28. Friedmann, P.P. Helicopter rotor dynamics and aeroelasticity: Some key ideas and insights, Vertica, 1990,14, (1), pp 101–121.Google Scholar
29. Ormiston, R.A. and Hodges, D.H. Linear flap-lag dynamics of hingeless helicopter rotorblades in hover, J Amer Heli Soc, April 1972, 17, (2), pp 2–14.Google Scholar
30. Takahashi, M.D. Active control of helicopter aeromechanical and aeroelastic instabilities, Dissertation, University of California, Los Angeles, 1988.Google Scholar
31. Johnson, W. Helicopter Theory, Princeton University Press, 1980.Google Scholar
32. Panda, B. and Chopra, I. Flap-lag-torsion stability in forward flight, 2nd Decennial Specialists’ Meeting on Rotorcraft Dynamics, NASA Ames Research Center, Moffet Field, California, pp 241–258, 7-9 November 1984.Google Scholar
33. Curtiss, H.C. JR Stability and control modelling, Vertica, 1988,12, (4), pp 381–394.Google Scholar
34. Diftler, M.A. UH-60A helicopter stability augmentation study, 14th European Rotorcraft Forum, Mailand, Italy, 20-23 September 1988, pp74.1–74.15.Google Scholar
35. Brockhaus, R. Flugregelung, Springer-Verlag, Berlin, Heidelberg, New York, 1994.Google Scholar
36. Föllinger, O. Entwurf konstanter Ausgangsrückführungen im Zustand- sraum, Automatisierungstechnik, January 1986, 34, (1), pp 5–15.Google Scholar
37. Wasikowski, M.E. Optimal Output Vector Feedback, Theory Manual, Georgia Tech Research Institute, Atlanta, Georgia, 1992.Google Scholar
38. Levine, W.S. and Athenas, M. On the determination of the optimal constant output feedback gains for linear multivariable systems, IEEE Transactions on Automatic Control, February 1970, 15, (1), pp 44–48.Google Scholar
39. Arnold, U. Blade stability of horizontally stoppable rotors, 17th European Rotorcraft Forum, Berlin, Germany, September 24-27 1991, pp 55.1–55.16.Google Scholar
40. Hammond, C.E. An application of Floquet theory to prediction of mechanical instability, J Amer Heli Soc, October 1974, 19, (4), pp 14–23.Google Scholar
41. Ewald, J. Untersuchung zur aeromechanischen Stabilität des Hubschraubers, Dissertation, ZLR-Forschungsbericht 91-05, Zentrum für Luft- und Raumfahrttechnik der Technischen Universität Braunschweig, Braunschweig, 1991.Google Scholar
42. Richter, P., Eisbrecher, H.D. and Klöppel, V. Design and first tests of individual blade control actuators, 16th European Rotorcraft Forum, Glasgow, Scotland, 18-20 September 1990, pp 111.6.3.1–111.6.3.7.Google Scholar