Design And Simulation Of 3000m Underwater Unmanned Vehicle

Unmanned underwater vehicle is an autonomous underwater unmanned platform which can dives into the underwater and is driven by its own energy.And it can replace human beings to complete various tasks in dangerous underwater environment.By carrying different mission modules,unmanned underwater vehicle can achieve different functions.Compared with common underwater vehicles,deep-water unmanned vehicles can work in the high pressure and deep sea environment and perform special tasks.However,the special environment also puts forward higher requirements for the vehicle.There are many problems to be solved.Based on this condition,the paper designs and simulates an underwater 3000 m unmanned vehicle.The contents are as follows:Firstly,according to the development trend at home and abroad and design goal of the vehicle,the general scheme design is carried out,which lays the foundation for the subsequent detailed design of the vehicle.The shape of vehicle is Myring,and the general layout is transverse sectional layout.The mechanical system is modular.The control system combines shore-based control system and shipboard control system,and the control algorithm is fuzzy PID algorithm.Secondly,detailed design and simulation of mechanical system is carried out with virtual prototyping technology and finite element theory,including power system,pressure system,non-pressure system and horizontal wing.The power system includes propulsion system,steering system,floating-and-sinking system and battery,whose floating-andsinking system adjusts the buoyancy of the vehicle by changing the volume of the oil bag.The pressure system adopts cylindrical pressure-resisting shell,and its material is aluminum alloy 7075.The results of theoretical calculation and simulation show that the pressure hull is of high stability.The non-pressure system adopts a thin shell structure without sealing,including head cabin,steering cabin,floating and sinking cabin and propulsion cabin.The horizontal wing is chosen as NACA0010.Then,the resistance performance of the vehicle is simulated by Fluent.The simulation models of different head and tail shapes are established to calculate the drag,and the variation curves between the shape parameters and the navigation drag are drawn.The results show that when the head and tail of the vehicle are sharper and the length is longer,the navigation resistance is smaller.Based on the results,the shape parameters are optimized to minimize the navigation resistance of the vehicle.Finally,the control system of the vehicle is designed based on the S7-200 PLC controller.The control system of the vehicle consists of shore-based control system and ship-based control system,whose communication between the two systems is via the communication module.According to the force and motion of the vehicle,the mathematical model of the vehicle is established.And on this basis,the fuzzy PID control algorithm of the vehicle is designed.The algorithm is simulated by Matlab.The results show that the fuzzy PID control algorithm is of well control effect.