Mathematical Simulation on Self-tuning Fuzzy Controller for Small Cylindrical Object Navigating near Free-surface

Based on the adaptive fuzzy control theory, a self-regulating fuzzy controller is designed for a small cylindrical object navigating near free-surface to minimize wave disturbance and to keep the object move in the desired depth. First, the near free-surface dynamics model of the cylindrical object is presented with the first and second order wave forces. Second, math simulation is introduced to testify the validity of the control method. The results obtained by a series of mathematical simulations demonstrate that the self-tuning fuzzy depth controller performs well in stabilizing the near-surface navigating object and in keeping it in the expected depth during the free-surface wave disturbance.