Study On The Motion Prediction For The Deep-water Buoyancy-driven Vehicle

With the continuous development of the national marine strategy,the status of marine construction and science examination is becoming more and more prominent.No matter the acquisition of marine resources or marine scientific research,it has been unable to bring enough value only in shallow coastal waters.At the same time,buoyancy as a driving force has the advantages of low energy consumption,low noise and low cost,and is suitable for marine exploration and exploration tasks.Therefore,we need to develop Deepwater Buoyancy-Driven Underwater Vehicle(DBDUV),which is suitable for deep sea and buoyancy as the main driving force.In the operation of a DBDUV,the main movement forms are floating and submerging.The prediction of buoyancy and submergence motion under buoyancy and gravity is the key to guarantee the successful release and recovery process,and is also the basis for further research on attitude adjustment and path planning.Aiming at the motion prediction of DBDUV,the Fast Prediction Method is proposed,and its motion rules and influencing factors are systematically studied.It contains the following aspects:1)Through dynamic numerical simulation,the vertical floating and submergence motion of the DBDUV are predicted and studied.2)Based on numerical simulation,a fast prediction method for vertical motion of underwater vehicle is put forward.By means of fast prediction method,the vertical floating and submergence motion of DBDUV and main factors affecting its motion are studied.3)The fast prediction method is applied to the prediction of the space motion of the underwater vehicle.The main factors that affect the motion of the buoyancy driven underwater vehicle are studied.4)Through the model experiment,the accuracy of the conclusions obtained by the numerical simulation and the accuracy of the proposed method are verified.Based on the research above,the paper draws the following conclusions:1)Fast Prediction Method of motion prediction of underwater vehicle has the advantages of high efficiency and flexibility for DBDUV,and can quickly and comprehensively study the influence factors of movement and movement;at the same time,the accuracy of Fast Prediction Method is verified by model test,is an effective method for motion of DBDUV.2)The change of the specific gravity and rudder angle of the buoyancy driven underwater vehicle will obviously change the situation of the underwater vehicle's snorkeling motion with time and the state when it reaches a stable state and the ability of horizontal motion in the space movement.3)Effect of initial emission velocity,fluid density thermocline and transverse disturbance for DBDUV's motion snorkeling is limited,will not affect the stable equilibrium state of motion,it will not affect the movement in the overall level;this illustrates the DBDUV's motion with stability.