Robust proportional derivative (PD)-like fuzzy control designs for diving and steering planes control of an autonomous underwater vehicle

In this paper, a highly non-linear model with six degrees of freedom (DOF) is used for the manoeuvring and depth control of an autonomous underwater vehicle (AUV). A simplified scheme to design a conventional fuzzy logic controller known as robust Proportional Derivative (PD)-like Fuzzy Controller (PD-FZ) is designed separately for diving and steering subsystems of an AUV and then applied for combined steering, diving and speed control functions. Simulation results are shown by using the slender form of the Naval Post-Graduate School (NPS, Monterey, CA) AUV. Results of simulation studies using a nonlinear AUV dynamics are presented under the presence of any bounded ocean currents orwave disturbances and results show that proposed controller gives robust performance against these disturbances and modeling nonlinearity. Waypoint acquisition based on line of sight guidance is used to achieve path tracking.