Research on Operational State Analysis and Motion Control of an Underwater Jacket Cleaning Robot

Maintaining mechanical stability and achieving precise motion control on cylindrical surfaces remain critical challenges for underwater jacket cleaning robots. To address these issues, a systematic mechanical model is initially established for a standard column (diameter 2000 mm, inclination angle 90°) to determine stable climbing conditions. By neglecting equivalent gravity, the critical constraint relationships between adhesion and propulsion forces are derived. Subsequent open-loop maneuvering simulations, conducted via a six-degree-of-freedom dynamic model in MATLAB/Simulink, reveal that the robot achieves a straight-line speed of 0.233–1.601 BL/s and a maximum steady-state thrust of ~80 N at rotational speeds between 500 and 3000 rpm, and this thrust level corresponds to a required maximum adhesion force of approximately 106.4 N. To enable autonomous navigation, a closed-loop control system is developed for two-dimensional waypoint tracking, integrating line-of-sight (LOS) guidance, a waypoint switching radius strategy, and a proportional-derivative (PD) controller. Simulation results verify that the robot successfully navigates through five sequential turning waypoints under operational constraints, maintaining well-converged position and heading errors, with the maximum heading deviation controlled within ±5°. All simulation validations in this study are completed through numerical simulations in the MATLAB/Simulink environment. These findings offer a practical reference and theoretical foundation for the autonomous control and reliable deployment of underwater cleaning robots.