Modeling and system identification of an autonomous underwater vehicle

This work aims to derive the kinematic and dynamic models governing the motion of an Autonomous Underwater Vehicle (AUV) and identify the hydrodynamic parameters of a prototype AUV. Good knowledge of such models enable the design of controllers for AUVs to perform path following or trajectory tracking tasks. The modeling process takes into account the primary hydrodynamic phenomena that affect the vehicle, including drag, restoring forces, and added inertia. Quaternions are employed to describe the attitude of the vehicle to avoid the singularity associated with the Euler angles based formulation. The finite element analysis package ANSYS is used to identify the drag and added inertia parameters that affect the vehicle. The approach taken in the system identification task yields results that match well with published analytical and empirical results.