Development of a Depth Controller for the SEAL Carrier

Abstract: The SEAL Carrier is a hybrid marine vessel capable of traveling both fast on the water surface and completely submerged.Due to the craft's hydrodynamical properties it is taxing on the pilots to keep the SEAL Carrier at a certain depth for longer periods of time, therefore it is desirable to have a depth controller. A model was developed to describe the forces from the actuators and the depth, pitch and speed controlled through a PI controller using a backstepping approach. The resulting controller was implemented and validated in Simulink and, as there exist a Simulink model of the craft, also tested and tuned. The Simulink implementation was turned into C++ code in order to be implemented on board the SEAL Carrier.The simulations provide promising results, though further tests should be performed to ensure the robustness of the controller, as the Simulink model has difficulties capturing all of the dynamics of the craft.