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Authors
David Saussie; Lahcen Saydy; Ouassima Akhrif; Caroline Berard Chiappa

Digital Object Identifier (DOI)
10.3182/20060705-3-FR-2907.00009

Page Numbers:
41-46

Index Terms
pitch rate control,modal multi-model control,self-scheduling,guardian maps,parametric uncertainty,robust control

Abstract
This paper describes a synthesis approach of a robust self-scheduled controller for the longitudinal pitch rate control system of a business jet aircraft. A fixed architecture controller with five tunable gains is sought in order to satisfy a set of constraints or handling qualities in the presence of mass and center of gravity uncertainties. On a nominal flight case, a set of satisfactory gains is found using eigenstructure assignment. The robustness of the controller against parametric uncertainty is then tested using guardian maps. In order to further improve the first controller robustness, a multi-model eigenstructure assignment is performed. A self-scheduled controller is computed to cover all mass and center of gravity variations. It is shown using Guardian Map theory that the final controller satisfies all the design criteria even when mass and center of gravity vary.

References

[1] Barmish, B. R. (1994). New tools for robustness
    of linear systems. New York: Macmillan.
[2] Constant, G., S. Chable, C. Chiappa and C. Döll
    (2002). Robustification of an h2 autopilot
    for flexible aircraft by self scheduling based
    on multi model eigenstructure assignment.
    In: International Council of Aeronautical Sciences
    . pp. 542.1-542.9.
[3] Gautrey, J. E. (1998). Flying qualities and flight
    control system design for a fly-by-wire transport
     aircraft. Ph.d. thesis. Cranfield University,
     College of Aeronautics.
[4] Hyde, R. A. (1996). H∞ aerospace control design
    - a VSTOL flight application. New York:
    Springer.
[5] Le Gorrec, Y., J. F. Magni, C. Döll and C. Chiappa
     (1998). A modal multimodel control design
     approach applied to aircraft autopilot design.
     AIAA Journal of Guidance, Control,
    and Dynamics 21(1), 77-83.
[6] Magni, J. F. (1999). Multimodel eigenstructure
    assignment in flight-control design. Aerospace
    Sciences and Technologies 3(3), 141-151.
[7] Magni, J. F., Y. Le Gorrec and C. Chiappa (1998).
    A multimodel-based approach to robust and
    self-scheduled control design. In: 37th IEEE
    Conference on Decision and Control, Tampa,
    Florida. IEEE. pp. 3009-3014.
[8] Saussié, D., L. Saydy and O. Akhrif (2003). Flight
    control design with robustness and handling
    qualities requirements. In: CCECE 2003 -
    Canadian Conference on Electrical and Computer
     Engineering. Vol. 3. IEEE. pp. 1749-
    1752.
[9] Saussié, D., L. Saydy and O. Akhrif (2006). Longitudinal
     flight control design with handling
    quality requirements. To appear in The Aeronautical
     Journal.
[10] Saydy, L., A.L. Tits and E.H. Abed (1990).
     Guardian maps and the generalized stability
     of parametrized families of matrices and polynomials.
      Mathematics of Control, Signals and
     Systems 3, 345-371.
[11] Tischler, M.B. (1996). Advances in aircraft flight
     control. London : Taylor & Francis.
[12] US Department of Defense (1990). Flying qualities
     of piloted aircraft. MIL-STD-1797A.