| In recent years, autonomous underwater vehicles (AUVs) have had an increasingly pervasive role in underwater research and exploration. Development and testing of an AUV is a lengthy and costly undertaking. Not only does one risk the loss of the vehicle due to various computer errors, but also the cost of a support crew, equipment, and facilities can be prohibitively expensive. Thus, computer modeling of the vehicle is important to the AUV designer.;This thesis describes the creation of a dynamics model of an autonomous underwater vehicle. Motion equations are integrated to obtain the position and velocity of the vehicle. External forces acting on the vehicle, such as hull and control plane hydrodynamic forces, are predicted for the full 3600 angle of attack range. This enables the simulation of high angle of attack situations. An accurate through-body thruster model is also incorporated into the simulation. The vehicle model is validated using experimental turning diameters of the ARCS vehicle.;The model is used to simulate two configurations of the C-SCOUT AUV: the Baseline Configuration and the Fully-Actuated Configuration. The simulation is used as a predictive design tool to evaluate and compare the performance of the two configurations before they have been fully developed. Results show the Fully Actuated Configuration to be less stable than the Baseline Configuration, due to the destabilizing effect of the forward control planes. The use of the through-body thrusters on the Fully Actuated Configuration reduce stability if the vehicle is in motion, especially if high thruster speeds are used at low forward velocities.;Two oceanographic sampling missions and a set of controllers are devised to help determine the relative benefits of each configuration. We find that the Baseline Configuration is suitable to missions where the vehicle maintains a forward speed. The Fully Actuated Configuration is found to be suitable to missions where it can use its through-body thrusters to change direction once it has stopped. |
