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An equation decoupling technique for identification of unstable aircraft with unsteady aerodynamic modelling

Published online by Cambridge University Press:  04 July 2016

J. Singh  and
S. C. Raisinghani
J. Singh
Affiliation:
Indian Institute of Technology, Kanpur, India
S. C. Raisinghani
Affiliation:
Indian Institute of Technology, Kanpur, India
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Abstract

A simplified trailing vortex concept has been used to model unsteady aerodynamic effects onto the mathematical model for an augmented unstable aircraft. An output error method with, and without, an equation decoupling technique in the frequency domain has been used for the estimation of parameters. The two approaches of estimation are compared for the cases where unsteady effects are included or excluded from the estimation model. It is shown that the incorporation of the equation decoupling technique makes the estimation algorithm robust with respect to initial guess values of the parameters. Finally, the inclusion of unsteady aerodynamics is shown to reduce the variation in the parameter estimates due to different control input forms.

Type
Research Article
Information
The Aeronautical Journal , Volume 97 , Issue 969 , November 1993 , pp. 321 - 327
Copyright
Copyright © Royal Aeronautical Society 1993 

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