Adaptive Path Following Control Based on Nonlinear Disturbance Observer for a Six Thrusters AUV

In this paper, we investigate the path following problem of a six-thruster autonomous underwater vehicle (SAUV) moving on the horizontal plane. Neural network adaptive PID control method based on NDO (BNNPID) is proposed. External disturbance and model uncertainty are taken into account in controller design. A nonlinear disturbance observer (NDO) is designed for disturbances observation. Theoretical derivation and simulation experiments have demonstrated the stability of this observer. We combine NDO and PID controller and use BP neural networks to adjust controller parameters online. In order to improve the correlation between controller parameters and system state, adaptive control is introduced. The robustness and effectiveness of the proposed controller are tested and validated through simulation results.