Dynamic Modeling And Simulation Of Vectored Thruster Autonomous Underwater Vehicle

In recent years, China has begun to focus on the development and utilization of theresources of the deep sea, which provides a wide range of backgrounds and needs ofUnderwater vehicle research. The rich resources of the deep sea will solve theproblems that we are facing shortage of resources. Due to Currents, waves, and workenvironment interference, the harsh marine environment, the request of underwatervehicle is more and more high. ROV research has been more mature, because AUVhas better performance, so the AUV is research hotspot. Many AUV often sail speedlow in executing the task. The maneuverability of traditional rudder control AUVunder low speed is low, cannot meet the control requirements. Vector propelled AUVhas good maneuverability at low speeds, which makes the vector-propelled AUV hasgreat significance.First we establish the vector advancing-AUV mathematical model, Because theAUV transverse rolling, motion in the horizontal plane and the longitudinal verticalmovement there exists coupling relation, we put forward the correspondingdecoupling method. Then we use the software simulation and empirical formula tocalculate the hydrodynamic coefficients. Finally, we research vector propulsion-AUVdynamic behavior on the basis of mathematical models and hydrodynamiccoefficients.The AUV that we use to research is comparison with the autonomous underwatervehicle (AUV) equipped with rudders, the AUV with vectored thruster has bettermaneuverability in low velocity and can achieve more precise positioning. Accordingto the characteristics of the AUV with single vectored thruster, the6-DOF kinematicmodel and dynamic model of the AUV are established using Newton-Euler method.In the dynamic model, the thrust force is considered as a function of the rotationalspeed of the propeller and the tilt angle of the vectored thruster. Dynamic behaviors ofthe AUV with single vectored thruster are simulated using five levels Four OrderRunge-Kutta method in MATLAB. The dynamic model is verified through physicaltests in lake.The main content of this paper are:1, The AUV approximation as a rigid body at not consider buoyancy system, usethe theorems of the rigid body dynamics and kinematics to derive a mathematicalmodel of AUV. 2, Use Fluent to calculate the hydrodynamic coefficients of the AUV. Find theempirical formula of the underwater vehicle that the shape of torpedo or submarines issimilar to the AUV to estimate hydrodynamic coefficients. Then Compare the resultsof two methods.3, Using MATLAB, a mathematical model and hydrodynamic coefficient toestablish the AUV simulation, simulate the weak coupling degree horizontal andvertical plane and the space spiral motion. At the same time analysis the simulationresults.