Manoeuvring simulation of the MUN Explorer AUV based on the empirical hydrodynamics of axi-symmetric bare hulls

Straight-ahead resistance tests and static-yaw runs up to 20°yaw angle for the axi-symmetric bare hull configurations of the “Phoenix” underwater vehicle that were performed in the 90 m towing tank at the Institute for Ocean Technology, National Research Council, Canada, provided empirical formulae for the drag force, lift force and turning moment that are exerted on such axi-symmetric torpedo-shaped hull forms. The empirical formulae were then embedded in a numerical code to simulate the constant-depth planar manoeuvres of the MUN Explorer autonomous underwater vehicle (AUV). The simulation model was first calibrated using the sea-trial data, and then was used to study the turning manoeuvres and to compare the simulation results with those from theoretical formulae based on the linearized equations of motion. The simulation results show non-linear changes in the hydrodynamic coefficients as the turning manoeuvre becomes tighter.