Development of a rotorcraft time domain system identification software

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2023-1-03
Aslandoğan, Ongun Hazar
A system identification software to identify stability and control derivatives for rotorcraft in hover and forward flight conditions is developed in this thesis. To demonstrate the identification procedure, a high fidelity nonlinear model of the H135 helicopter is used. Frequency sweep, 3211 and 2311 type inputs are given to the nonlinear helicopter model to generate test data. The procedure is carried out by identifying a state space model structure in time domain using output error method with Levenberg-Marquardt algorithm. Initially, a model reduction routine is carried out to drop redundant derivatives in the state space linear model structure. By making use of state and control delays, higher order dynamics introduced to model response are identified with greater accuracy. The identified system is verified in frequency domain using frequency sweep maneuvers, whose time domain signals are converted to frequency domain via discrete Fourier transform.

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Citation Formats
O. H. Aslandoğan, “Development of a rotorcraft time domain system identification software,” M.S. - Master of Science, Middle East Technical University, 2023.