Research On Motion Control Technology Of Underwater Cage Cleaning Robot

With the rapid development of underwater robot technology and the gradual maturity of control algorithms,using underwater robots to clean underwater net cages has become a mainstream trend.Currently,most deep-water net cage farming enterprises in China still use the primitive mode of divers for underwater cleaning operations.This method not only has high labor intensity,low efficiency,and high costs,but also can cause harm to the human body during long-term underwater operations.Using underwater robot automation to replace manual cleaning can greatly improve work efficiency.Therefore,it is of great significance to study the motion control technology of underwater net cage cleaning robots.This thesis focuses on the motion control technology of underwater robots for net cage cleaning,and carries out research work on the motion model,control algorithm,and overall system design of underwater net cage cleaning robots.The specific contents are as follows:(1)Based on the basic principles of kinematics theory,the motion laws of underwater robots are analyzed and the kinematic model of a six-degree-of-freedom underwater cage cleaning robot is improved.Through dynamic analysis of the structural characteristics of the underwater robot and its actual force situation,a more accurate dynamic equation is established,and control models for the forward and backward movement,heading movement,and depth control of the underwater robot are designed.(2)A fuzzy PID algorithm-based motion controller is designed to address the non-linear control problem during the movement of an underwater cage cleaning robot.The fuzzy control rules are optimized,considering the motion characteristics of the underwater cage cleaning robot.A simulation system is built to compare and verify the control performance of the algorithm with a traditional PID-based controller.(3)Based on the operational requirements and technical specifications of underwater robots,the overall architecture of an underwater cage cleaning robot is designed.To achieve stable motion of the underwater cage cleaning robot,the shape of the ROV(Remotely Operated Vehicle),the sealed pressure-resistant compartment,the thrusters,and the cleaning disk are analyzed and designed separately.The DICE(Decision--Information--Control--Execution)motion control system architecture is proposed,and a selection analysis of the electrical control system for the underwater robot is carried out.(4)An experimental prototype of an underwater cage cleaning robot is built,and the hardware and software systems of the ROV are designed and debugged.Propulsion tests and underwater motion control tests of the prototype are carried out,and the feasibility and applicability of applying fuzzy PID control algorithms to underwater cage cleaning robots are verified.