Unmanned seaplanes are special fixed-wing airplanes which can take off and land on water. According to their technological characteristics, seaplanes can be divided into two categories: floatplanes and flying boats. Because of their unique features, unmanned seaplanes have lots of civilization and military utilities and research on unmanned seaplanes is of great theoretical significance and practical value. As the hydrodynamic forces estimation for unmanned seaplanes is very complicated and sea states are severe and unpredictable, the researches on the modeling, mathematical analysis, control design and unmanned techniques for seaplanes have few substantial developments. Although there are some unmanned seaplanes reported to be successfully developed in American and England, no relevant researching result has been published. There are still lots of theoretical and practical problems for unmanned seaplanes. According to the research results from high speed boats and flight control technologies, two mathematical models based on Savitsky semi-empirical method and two-dimensional strip theory respectively are established for an unmanned flying boat. Through simulations, the forces, motions and dynamic characteristics of the flying boat are analyzed. Then, two automatic taking-off control algorithms based on active disturbances rejecting control method, nonlinear dynamic inversion control method and T-S fuzzy logic control system are proposed. The research work can be divided into following parts: (1) The dynamic characteristics of the flying boat are analyzed when taking-off on smooth water, and a mathematical model for the vertical motions of the flying boat has been established by Savitsky semi-empirical method which is corrected based on the sharp features of the flying boat and requirements for dynamic system simulation. This model has been verified by comparing the simulation data of the model with the experimental data. (2) The Savitsky semi-empirical method is a stable hydrodynamic forces estimation method, which means that it is difficult to simulate the dynamic process of the unmanned flying boat. And the Savitsky semi-empirical method doesn’t consider the nonlinear hydrodynamic influences of waves. In order to deal with these problems, a mathematical model based on a two-dimensional strip theory and Savitsky semi-empirical method is established. Some corrections to the two-dimensional strip theory are made based on the sharp of the flying bo...
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