Conceptual Design And Sailing Stability Study On Water Air Amphibious Unmanned Ship

In recent years, the maritime rights and interests have been paid more and morenational attention, for this reason, ships and marine structures which are used for exploitingocean sources, cruising and monitoring become the focus of scholars and experts in relatedfields, among them, for the unmanned craft favored. While, the unmanned surface vehicle(USV) has a big disadvantage in high sea condition, it cannot work properly. This paperpresents a water-air amphibious craft concept boat in view of this situation, design andmanufacture an unmanned craft model, and research on its stability of navigation throughthe experiment and simulation. Studying on the stability of sailing in this thesis mainlyincludes two aspects: one is the seakeeping surface navigation, the other is the attitudestability while flight.Seakeeping research mainly by rolling tests in silence water, pitching-heaving tests insilence water and self-propulsion rolling tests, nonlinear mathematical models of rolling andpitching-heaving are established, the uncertain coefficients are determined via systemidentification method witch based on genetic algorithm, the reference objects are deducedfrom second-order system vibration function, by comparing and analyzing the damping andrestoring moments between the mathematical models and referent objects, the variations ofnonlinear damping and nonlinear restoring moments in rolling with the distance betweenmain hull and side hull are got. By similar method, obtained the variations of heavingacceleration’s affect to damping and restoring moment in pitch with different drafts, and thevariations of rolling with different rotating angle rate and rotating radius.Study on the stability of attitude is realized through the simulation of Simulink moduleof MATLAB software, this paper designed an active disturbance rejection controlprocedures for controlling the flight attitude of amphibious unmanned craft, and verified theeffectiveness and robustness of the control program via an example.The above researches could provide reference for future design of unmanned craftwitch operated in high sea condition.