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Flight control system design with H loop-shaping approach through non-diagonal weights

Published online by Cambridge University Press:  03 February 2016

R. Panesi
Affiliation:
[email protected], Department of Aerospace Engineering, University of Pisa, Pisa, Italy
G. Mengali
Affiliation:
[email protected], Department of Aerospace Engineering, University of Pisa, Pisa, Italy

Abstract

This paper deals with the design methodology of multi-variable flight control systems through a H loop-shaping technique. A new procedure for the design of non-diagonal pre-and post-compensators is described. In particular, important improvements over existing methods are introduced to both make the selection of weights easier and to contain the order of the resulting controller. The new procedure can be easily managed through suitable Matlab commands and functions, thus simplifying the whole algorithm implementation and providing an effective control system design with a minimum effort. Two typical design problems are addressed: a pitch pointing control system and a lateral controller for coordinated turns. In both cases, a good decoupling between existing channels is obtained by means of a non-diagonal pre-compensator which shapes the plant transfer function, and provides the desired response settling time. The design approach is particularly effective even for nominal plants with strong cross-coupling between channels. The design procedure is illustrated with the aid of a Matlab/Simulink model of a single seat fighter aircraft. We show that a trade-off between the conflicting requirements of fast response and moderate use of control surfaces can be easily managed by varying the constant terms of the diagonal post-compensator.

Type
Research Article
Copyright
Copyright © Royal Aeronautical Society 2009 

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References

1. McFarlane, D. and Glover, K., Robust Controller Design Using Normalised Coprime Factor Plant Descriptions. Berlin: Springer Verlag, 1990.Google Scholar
2. Bates, D. and Postlethwaite, I., Robust Multivariable Control of Aerospace Systems, 2002, ser. DUP Science. Delft: Delft University Press.Google Scholar
3. Glover, K. and McFarlane, D., Robust stabilisation of normalised coprime factor plant descriptions with H bounded uncertainty, IEEE Transactions on Automatic Control, 1989, 34, pp 821830.Google Scholar
4. McFarlane, D. and Glover, K., A loop-shaping design procedure using H synthesis, IEEE Transactions on Automatic Control, June 1992, 37, (6), pp 759769.Google Scholar
5. Skogestad, S. and Postlethwaite, I., Multivariable Feedback Control, Analysis and Design, 1996, Chichester, UK, John Wiley & Sons.Google Scholar
6. Hyde, R.A. H Aerospace Control Design–A VSTOL Flight Application, Springer Verlag, 1995.Google Scholar
7. Papageorgiou, G. and Glover, K., A systematic procedure for designing non-diagonal weights to facilitate H Loop-Shaping. San Diego, CA, USA: 36th IEEE Conference on Decision and Control, December 1997.Google Scholar
8. Forssell, L. and Nilsson, U., ADMIRE The aero-data model in a research environment Version 4.0, Model Description, Swedish Defence Research Agency, Systems Technology, SE-164 90 Stockholm, Tech. Rep. FOI-R-1624-SE, December 2005.Google Scholar
9. Francis, B., A COURSE IN H CONTROL THEORY. BERLIN, GERMANY: Springer Verlag, 1987, pp 84104.Google Scholar
10. Zhou, J. with Doyle, K., Essentials of Robust Control. Upper Saddle River, New Jersey, USA: Prentice Hall, 1998, pp 233244.Google Scholar