The Dynamic Simulation Of Underwater Vehicle

The underwater vehicle is a kind of robot that works underwater. It’s also known as the underwater robot. The environment underwater is too harsh for people to work in it, because people can hardly bear the high pressure underwater, and it’s too dangerous for people to work in the environment without oxygen. But the underwater vehicle may just ignore these factors. The underwater robot can dive into the water and complete all kinds of repair and recovery work instead of people. We may say the underwater vehicle has become an important tool for the development of the ocean.In this paper we established the kinematics equations of underwater vehicle based on the submarine maneuverability theory, and complete the simulation of the motion of underwater vehicles on the basis to verify the correctness of dynamic model. In this paper we made certain exploration on the movement of the underwater vehicle.The following contributions have been made.1. Through the research of the submarine maneuverability technology, contact with engineering practice, we made systematic analysis of the factors that influence the underwater vehicle movement. We established six degree of freedom nonlinear dynamic model of underwater vehicle, take the vehicle roll and translation adjusting device and buoyancy adjusting device into account. It can be a reference to the design and research of similar aircraft.2. Obtained the hydrodynamic derivatives through the empirical formula of approximate calculation, and compare them with the hydrodynamic derivatives that obtained from fluid dynamic simulation software to choose more accurate numerical value. Then we analyzed the advantages and disadvantages of current methods that obtained the hydrodynamic derivative.3. We did the simulation with the computer simulation software. In the paper, we use the four step Runge-Kutta method to solve the nonlinear equations. It has been verified that the four step Runge-Kutta method is more accurate compare with other similar method. This paper studied the overall dynamic characteristics of the underwater vehicle respectively from the horizontal plane, vertical plane and three-dimensional simulation.Most existing mathematical model of the underwater vehicle is too simple and neglected the coupling effects between different freedoms. But it often has obvious coupling relationship between different freedoms of the underwater vehicle. It’s too dangerous for people to just ignore it. In this paper, we further studied the coupling relationship in the underwater vehicle, and put forward corresponding decoupling approach. It has a guiding significance for the study of underwater vehicles.