Ergazi, Nazife Ege
The longitudinal dynamics of F-16 aircraft in a level trim, unaccelerated flight are identified using frequency-domain system identification techniques. The nonlinear system is excited by sine sweep elevator input, and angle of attack and pitch rate responses are collected. Detrending and windowing are applied to time-domain data and are converted to the frequency-domain by applying Fast Fourier Transform (FFT). The smooth spectral estimates are found from the transformed data, allowing frequency responses and coherence to be calculated. Under the guidance of coherence, transfer functions are estimated to the frequency response data. Then, nondimensional derivatives are extracted from these identified transfer functions. Finally, the identified model is verified in the time domain.


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The aerodynamics of insects flying at low Reynolds numbers is considered for Micro Air Vehicles (MAV) designs. The aim of this study is to analyze different flapping wing models and to predict generated forces and vortices around the wings. The analyses are significant for understanding properties of flying animals like birds, insects and for improving MAVs more. For three insect species (namely, bumblebee, hawkmoth, and hummingbird), three dimensional (3D) wing models are numerically analyzed at different ...
Citation Formats
N. E. Ergazi, “FREQUENCY-DOMAIN SYSTEM IDENTIFICATION OF F-16 LONGITUDINAL DYNAMICS,” M.S. - Master of Science, Middle East Technical University, 2022.