Research On Simulation And Control Technology For Bionic Underwater Vehicle

In recent years, the demand and desire to explore and utilize the deep-sea natural resource have provided a significant moment to underwater vehicles research. To overcome certain shortcomings of conventional Underwater Vehicle (UV) and to find more excellent propulsion and control systems, more and more attention have been given to the bionic technology, which have already been one of the most important fields in the UV research.Fish swims fast, efficiently, flexibly and quietly. So it's important to utilizing fish's swimming mode on the UV instead of traditional screw propeller and rudder. The motivation of this thesis is to design a fish-like propulsion and control method, which can be used on the UV, through the research on the swimming theory of fish.In this thesis, we summarize the bionic UV technology, and predict its trend of development. Then a detailed introduction is given to a bionic UV, named "FangSheng-I", developed by the Underwater Vehicle Technology Lab (UVTL) of Harbin Engineering University. Firstly, the system design and the circulating water channel experiments, the water tank experiments and the sea experiments of "FangSheng-I" are introduced. Secondly, the hydrodynamic performance of "FangSheng-I" is discussed. The unsteady hydrodynamic characteristics of a rigid and a flexible lunate tuna-tail are analyzed numerically by the low-order potential based surface panel method, the effects of many parameters are investigated, and the added-mass of "FangSheng-I" are obtained. Then the six degrees of freedom motion simulation model of "FangSheng-I" are constructed, with emphases laid on the differences between the bionic UV and traditional UV, such as the propulsion system, the control system and the variation of the added-mass.Simulation results are used to validate the rationality of the model. And at last, by discussing the movement capability of "FangSheng-I" according to the results of its water tank experiments, we give a method of its motion control. Simulation experiments are also done to validate the method.Through the research and experiments in this thesis, we give a conclusion that the fish-like propulsion and control are feasible to the UV. More detailed research should be done on the special swim method of fish.