Structure Design And Analysis Of Small Autonomous Underwater Vehicle For Shallow Water

The survey of shallow waters such as shallow seas and rivers is often carried out manually,which is inefficient and dangerous.With the development of science and technology,underwater vehicles are widely used,at present,the underwater vehicle with cables is still widely used,however,its work is limited by the length range of cables,the increase of resistance and inflexibility.Aiming at these problems,a small autonomous underwater vehicle is proposed,and its structural design and analysis are carried out in this thesis,the following results are achieved:(1)The application requirements of small autonomous underwater vehicle are analyzed,the design indexes of small autonomous underwater vehicle are proposed,and the overall design scheme of small autonomous underwater vehicle is given by using the modular design concept;at the same time,the shape of the vehicle was designed by bionic method;in the meanwhile,the strength and stability of the pressure hull,electronics and power supply cabin are analyzed by theoretical calculation and finite element method,the results show that the strength and stability meet the requirements in the underwater 30 m.Finally,the design of the small autonomous underwater vehicle body structure is completed,and its prototype model is established.(2)On the basis of the kinematics model and dynamics model of the autonomous underwater vehicle,the fluid characteristics of the autonomous underwater vehicle are simulated and analyzed by using the software Fluent,the relationship between hydrodynamic force and velocity with the velocity and pressure nephogram of autonomous underwater vehicle under hydrodynamic force are obtained,at the same time,the simulation results are compared with those under scale ratio.The results show that the structural shape and overall layout of the designed autonomous underwater vehicle are reasonable.(3)For analyzing the performance of autonomous underwater vehicle,an experimental platform,an indoor small open DC water tunnel,is designed and simulated,in the meanwhile,an experimental platform is built based on the analysis results;furthermore,the experimental platform is calibrated and verified to meet the experimental requirements.Finally,the accuracy of the hydrodynamic simulation results is verified by measuring the relationship between the hydrodynamic force and the velocity of the underwater vehicle and comparing with the simulation results.(4)In order to further verify the structural stability of the autonomous underwater vehicle,the static simulation analysis of the whole vehicle subjected to hydrodynamic force is carried out,the calculation results are far less than the material strength limit,meeting the environmental requirements.