Research On UUV Path Following And Weather Optimal Dynamic Positioning

Nowadays, UUV is the hot topic among a lot of countries. It plays a more and more important role in our daily life, and even can replace human beings to complete some special tasks. Therefore, it is of great significance to study of an UUV.This paper has researched on path following and weather optimal dynamic positioning of an UUV, and they are the typical movement of an UUV, and they are the foundation of an UUV to compllete other complex tasks. To improve the path following precision which can help UUV to complete more delicate tasks,and it can make an UUV navigate for a long time with weather optimal dynamic positioning during the tasks at the same speed situation.Firstly, this article selects Minesniper MkⅡ as the research object, and the UUV’s six degrees of freedom mathematical model is set up. We get the planar model which including the ocean current by simplifying the six DOF model, and prove it to be validated through some simulation experiments. For the design of the dynamic surface controller (DSC), we transform the planar model for the heading control model and the longitudinal velocity control model further, and convert the control model into the active disturbance rejection control (ADRC) standard form at the same time, for the sake of the design of DS-ADRC.Secondly, we study the guidance system of the UUV, and obtain real-time desired heading with line of sight guidance (LOS) method for path following. The system will eventually appear steady-state tracking error in the view of the traditional LOS method, when it is under the ocean current. We revise the expected heading angle which generated by LOS method by introducing the sideslip, and ensure the system tracking error converge to zero.The reference model method with which the speed is limit is used for weather optimal dynamic positioning to generate real-time expectation of longitudinal velocity, only in this way can guarantee the UUV to realize tracking for the desired speed.Then, the DSC technology is applied to the two typical motion control of UUV by the research of it, and we design the heading controller and longitudinal velocity controller based on it. This method can avoid differential explosion phenomenon in traditional backstepping,and the stability of the controller is proved. The simulation results also show the effectiveness of the controller which based on DSC.Again, it is known that the DSC relies on the UUV’s precise mathematical model, while it is difficult to obtain it. This paper combines the DSC technology with ADRC technology,and it reduces the dependence on the model of the UUV, and the controller which designed based on DS-ADRC is proved to be stable. In the simulation experiments, we make a contrast between DSC and DS-ADRC, the results show strong anti-disturbances ability.Finally, we combine this research with the actual tasks of UUV through a designed case,which not only reflects the practically of this work, but also its integrity of this article.