Research On AUV Path Planning Based On Improved RRT Algorithm

AUV(autonomous underwater vehicle)is one of the most common and important tools for ocean exploration in the world.It is of great help in deep-sea scientific research,commercial development and military affairs.Path planning is one of the important technologies in AUV research.It is the basis of autonomous underwater navigation.The accuracy of path planning determines the accuracy of AUV in autonomous underwater operation.In this paper,the path planning technology of unknown underwater environment is studied.This paper introduces the research status of AUV,introduces and summarizes the classification of path planning and common planning methods.In order to restore the real map environment as much as possible,this paper uses the region growth and expansion corrosion algorithm to deal with the satellite map binary,and establishes a variety of motion models to describe the movement of obstacles.In this paper,Rapidly-Exploring Random Tree(RRT)algorithm is used as the basic algorithm of path planning.The basic principle,advantages and disadvantages of RRT algorithm are analyzed.Based on the application characteristics of RRT,an improved method combined with a * algorithm is proposed.In view of the feasibility and optimization problems of the path,a secondary optimization process combining pruning strategy and Bessel optimization is proposed.In order to verify the feasibility of the improved algorithm,comparative simulation experiments are carried out.Aiming at the path planning problem of AUV in overall environment,the influence of ocean current on AUV is analyzed.Combined with the characteristics of AUV,the corresponding cost functions of distance cost and energy consumption cost are designed respectively,which are brought into the improved RRT algorithm.Then,the global paths with and without ocean current are simulated and verified,and the global paths of optimal distance and energy consumption are obtained respectively the reliability of the algorithm.Aiming at the local planning problem of AUV in unknown environment,combined with the characteristics of AUV borne sonar,a rolling window is established,and the relevant update rules and sub target point selection rules are set up.In the face of underwater dynamic threat,this paper uses interactive Kalman filter to complete the dynamic trajectory estimation of dynamic obstacles,and establishes the collision avoidance rules.Finally,the feasibility and reliability of the algorithm are verified through the comparative simulation of the methods.