Research On Motion Control Of Inspection Robot For Pressure Water Supply Pipeline

In response to the current problem of leak detection in urban water supply networks,traditional manual inspection is difficult to meet current needs and electronic equipment,mainly pipeline inspection robots,is gradually being used in inspection projects.Among them,the underwater robot,as a tool for underwater operation,has been developing rapidly.The cruise control of the underwater vehicle on the centerline of the pipeline is the basis to complete the inspection work,so the design and research of the underwater vehicle controller is extremely important.This topic originates from the requirements of enterprises,and takes ROV as the platform.In order to achieve cruise control of an underwater robot on the centreline of a pipeline,this paper designs a motion controller based on image processing technology.The main work carried out is as follows:Firstly,the research status and significance of pipeline inspection robot are analyzed,and the pipeline inspection robot used in this paper is established as ROV.The conversion relationship between ROV carrier coordinate system and ground coordinate system is obtained.According to the force analysis of ROV,the four degree of freedom motion equation of the underwater vehicle is derived from the dynamic equation;Then use the ANSYS Fluent module to do fluid simulation to simulate ROV advance and retreat,diving,rolling and yaw motion,and use the CFD method to calculate the hydrodynamic parameters in the dynamic equation to obtain a complete four degree of freedom dynamic model.Then,a set of automatic detection algorithm based on image processing technology is integrated to extract the coordinates of the dark area centroid,and the coordinates are converted into information that can be read by the robot through a three-dimensional mapping algorithm.Combined with LOS navigation algorithm,calculate the heading angle required by the next dark area centroid point that ROV expects to track,track the heading angle to eliminate the track error,use the traditional fuzzy technology and the fuzzy technology optimized by improved genetic algorithm to design the heading controller,speed controller and vertical depth controller respectively,and use MATLAB simulation results to compare,the fuzzy controller optimized by improved genetic algorithm has good robustness and high control accuracy.Finally,through the integrated simulation of the ROS system,the lake test and the actual pressure water supply pipeline experiment,the results show that the ROV path tracking controller proposed in this paper is effective and feasible.