Direct adaptive flight envelope protection

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Date

2016

Author

Gürsoy, Gönenç

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In this thesis, two vital signals to enable flight envelope protection, namely the onset to the flight envelope, i.e. limit margin, and the available control travel to reach the limit boundary, i.e. control margin, are estimated using adaptive neural-network-based approximate models. An adaptive learning method, known as concurrent learning, is used to update the adaptive weights online with guaranteed signal bounds. Current and previously recorded data are used concurrently in the weight update. Minimum singular value maximization method is used to record necessary data online for concurrent learning. Results showed better convergence properties of the network weights compared with results in the literature in which only the current data is used for network weight updates. New methodologies are introduced to calculate limit and control margins from approximate online models. None of the introduced methods require online iterations and therefore remove a previously introduced assumption related to iteration convergence. Nonlinear fixed wing and rotary wing aircraft models are used to show the effectiveness in simulation for estimating limit and control margins and avoiding the limit through artificial control saturation.

Subject Keywords

Flight control., Fly-by-wire control., Airplanes

URI

http://etd.lib.metu.edu.tr/upload/12620050/index.pdf
https://hdl.handle.net/11511/25688

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

G. Gürsoy, “Direct adaptive flight envelope protection,” Ph.D. - Doctoral Program, Middle East Technical University, 2016.