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Efficient and robust algorithms for trim and stability analysis of advanced rotorcraft simulations

Part of: 75 year anniversary of Aeronautical Engineering at Glasgow University

Published online by Cambridge University Press:  04 July 2016

J. S. G. McVicar  and
R. Bradley
J. S. G. McVicar
Affiliation:
Department of MathematicsGlasgow Caledonian University, Glasgow, UK
R. Bradley
Affiliation:
Department of MathematicsGlasgow Caledonian University, Glasgow, UK
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Abstract

This paper derives innovative techniques for use in the trimming and stability analysis of advanced rotorcraft simulations. It begins by exploiting the symmetry of the rotor to produce an efficient definition of periodic trim which is applicable to rotorcraft simulations. This definition is then expanded to produce a trimming algorithm which is capable of concurrently ascertaining the initial conditions and control inputs necessary to trim latest generation simulation models to a specified periodic trim state. The algorithm is based on a periodic shooting approach with Newton-Raphson iteration and exploits the symmetry of the rotor to minimise computational workload. The definition of periodic trim is then further developed to produce a technique by which the stability characteristics of rotorcraft can be ascertained from advanced simulation models. This technique is based on a Floquet approach and again exploits the symmetry of the rotor to reduce computational burden. The paper concludes by presenting results obtained when the stability characteristics of a tiltrotor simulation model are investigated.

Type
Research Article
Information
The Aeronautical Journal , Volume 101 , Issue 1008 , October 1997 , pp. 375 - 387
Copyright
Copyright © Royal Aeronautical Society 1997 

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References

1. Padfield, G.D. Theoretical modelling of helicopter flight mechanics: development and validation, Proceedings of the 16th ICAS Conference, London, 1988.Google Scholar
2. Aponso, B.L., Johnston, D.E., Johnston, W.A. and Magdaleno, R.E. Identification of higher order helicopter dynamics using linear modelling methods, J Amer Heli Soc, July 1994, pp 3–11.Google Scholar
3. McVicar, J.S.G. and Bradley, R. A generic tiltrotor simulation model with parallel implementation and partial periodic trim algorithm, Proceedings of the Eighteenth European Rotorcraft Forum, Avignon, France, September 1992.Google Scholar
4. ANON, Aeronautical design standard, handling qualities requirements for military rotorcraft, ADS-33C, August 1989.Google Scholar
5. Peters, D.A. and Hohenemser, K.H. Application of Floquet transition matrix to problems of lifting rotor stability, J Amer Heli Soc, April 1971, pp 25–33.Google Scholar
6. Glauert, H. A General Theory of the Autogyro, ARC RI&M 1111, 1926.Google Scholar
7. Peters, D.A. and HaQuano, N. Dynamic inflow for practical applications, J Amer Heli Soc, Technical Note, 1988.Google Scholar
8. McVicar, J.S.G. and Bradley, R. Robust and efficient trimming algorithm for application to advanced mathematical models of rotorcraft, J Aircr, 32, (2), pp 439–442.Google Scholar
9. Hansen, R.S. Toward a better understanding of helicopter stability derivatives, J Amer Heli Soc, January 1984, pp 15–24.Google Scholar
10. Pontryagin, L.S. Ordinary Differential Equations, Addison-Wesley Publishing, Reading, Massachusetts, 1962.Google Scholar
11. Peters, D.A. and Hohenemser, K.H. Application of the Floquet transition matrix to problems of lifting rotor stability, J Amer Heli Soc, April 1971, pp 25–33.Google Scholar
12. McVicar, J.S.G. and Bradley, R. Efficient algorithms for trimming and stability analysis of advanced rotorcraft simulations, Proceedings of the CEAS Symposium on Simulation Technology, Delft, The Netherlands, October 1995.Google Scholar
13. Peters, D.A. Fast Floquet theory and trim for multi-bladed rotorcraft, Proceedings of the 51st Annual Forum of the American Helicopter Society, Fort Worth, Texas, May 1995, pp 444–459.Google Scholar
14. Padfield, G.D. Helicopter Flight Dynamics, Blackwell Science, London, 1996.Google Scholar