Underwater Glider: Design, Optimization And Motion Simulatiom

Underwater glider is a new type AUV without external activepropulsion, which is driven by its net buoyancy and controlled rely onexternal control surface and internal mechanism. As a carrying platform,glider has many useful applications, notably in oceanographicinvestigation and environment sensing and data collection because of itsadvantages of lower power consumption, lower cost and capability forlong-endurance, etc. Since the underwater glider concept was put forward,Europe and America have been formed comparatively mature theoreticalsystem and engineering application system now. But our country is still atthe initial stage in the fields of engineering applications, and has big gapwith foreign. The underwater glider is studied in this paper which hasreasonable theoretical significance and application prospects.There are three main themes within this paper:1. A prototype of underwater glider is developed, includes generalarrangement, external molded lines and structure design, buoyancyadjusting mechanism, attitude adjusting mechanism, control system design,system integration and tank experiment. In the design, the water bladder isarranged inside the pressure hull, which avoid the bad effect that the deepwater pressure make on the volume and shape of water bladder, increasethe system stability; and the water bladder is arranged on the stem withinthe vehicle, which would provide positive moment when the systemtransforming the gliding attitude, reduce the system regulation time andincrease stability; and the tank experiment of the prototype verify that thefundamental principle of underwater glider is feasibility. 2. Established mechanical model and motion mathematical model ofthe prototype in the vertical plane to research the motion characteristics ofunderwater glider. And the downward gliding motion of prototype in thevertical plane was simulated. From the results of simulation, we could tellthat the water bladder arrangement design has truly reduced the glidersystem’s regulation time and increase the stability.3. Base on the glider prototype, applying computational fluiddynamics software CFD to research glider’s hydrodynamics characteristicswhen gliding in the vertical plane, and optimize airfoil profile design andwings layout design. Research the advantages and disadvantages ofhydrodynamic properties between plate wings and NACA0006airfoilprofile when glider moving through incompressible fluid at slower speeds.The effect of NACA0006airfoil’s sweep back angle on the prototype’shydrodynamic characteristic under different attack angles is studied, andthe layout of the wing’s sweep back angle is analyzed and optimizedaccordingly to the research above.