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Modeling a Small-size Unmanned Helicopter Using Optimal Estimation in The Frequency Domain

In this paper, a semi-decoupled state space model of a small-size helicopter is developed for hovering conditions in order to simplify the model identification process. An optimal estimation algorithm in frequency domain is proposed and implemented to estimate the parameters in the state space model using real flight data collected from a SERVOHELI-40 small-size unmanned helicopter. The accuracy of the identified model is verified by simulation in time domain, using a different set of hovering flight data. The results have shown the accuracy of the developed semi-decoupled model and the effectiveness of the proposed optimal estimation algorithm in frequency domain.