Development Research on Vertical Depth-Fixing Control of Small-Size ROV

Based on the mechanical structure design of the vehicle system and the dynamics generalized six degrees of freedom equation, the vertical depth-fixing control model is established under multiple constraints, which is designed to solve the posture and position control problem of remotely operated vehicle, And the transfer functions of vertical depth-fixing controller, motor and propeller are obtained. Depth-fixing PID controller and fuzzy PID controller are founded through the study of PID control and fuzzy PID control theory in SIMULINK library, and the final experiment validation, simulation and experimental results show that fuzzy PID control performs better than PID control. The former can regulate smaller overshoot amount with shorter adjust time, while obtain faster response convergence speed. And depth control in vertical has good stability and ability against interference.