Research On UUV Unknown Boundary Detection And Boundary Tracking

As a new and intelligent underwater unmanned equipment,UUV can perform numerous oceanographic exploration tasks.Among them,harbor patrol,island survey and Marine structure survey are typical applications of UUV in carrying out oceanographic survey.Among the three types of applications,it is required that the observation and detection of UUV should have the autonomous tracking and navigation ability of the contour boundary of underwater objects such as ports,islands and Marine structures,so as to achieve better observation and detection effect of underwater objects.In particular,when the contour boundary of an object in the water is unknown,UUV needs to detect the unknown contour boundary online first,and then use the boundary information detected online to generate tracking behavior for tracking.In the process of UUV to track the boundary of objects in water,firstly,it is required that the UUV and the contour boundary of objects in water should keep the fixed distance to track the navigation.Second,UUV and objects in the water can not be collision,to ensure safety;Third,when the UUV detection information of unknown boundary is insufficient or lost,it is required that the UUV can search the boundary again.However,the boundary of underwater objects faced by UUV is usually irregular and complex,and only local and small amount of boundary information can be obtained by UUV detection equipment.Therefore,the research on the patrol tracking method of unknown boundary based on forward-looking sonar in this paper is of great significance in both scientific research projects and practical applications.The main research content of this paper is divided into the following parts:First,aiming at regular boundary tracking navigation,this paper uses multibeam forward looking sonar to extract features of online detection information of unknown boundary,so as to obtain real-time local boundary Angle information and distance information from UUV to boundary.The cruising tracking controller is designed,and the optimal command heading is obtained by fusing the calculated command heading based on the information of the boundary Angle with the correction quantity of the command heading based on the fuzzy control algorithm,and the distance tracking of the boundary is realized indirectly through the control method of the fixed Angle.Second,based on the rules,and complicated boundary tracking,when navigating through the different boundary tracking to evaluate likely scenario analysis,summed up the sonar detection information loss and UUV collisions with border two situations,for in both cases,the design of a switching control system based on behavior strategy,including tour edge tracking,boundary search and security response of three parts,respectively to perform actions tour edge tracking,rotation detection behavior and directional guidance.Third,this paper verifies and analyzes the switch control system of UUV line-tracking method and multi-behavior strategy through simulation.First of all,smooth boundary,concave boundary,convex boundary and complex boundary are established.UUV tracks the navigation of four kinds of boundary,which verifies the control effectiveness of each part of the switching control system and the switching stability between the three parts.Then,according to different expected tracking distance and different speed,the influence of UUV tracking effect is studied.Finally,the island boundary model is established by taking the island satellite map as an example,and the control method and strategy proposed in this paper are verified.The simulation results show that UUV can meet the distance tracking requirement proposed in this paper when tracking unknown boundary,and achieve good tracking effect,which has practical value in engineering practice.