Nonlinear Model-Based Tracking Control of Underwater Vehicles With Three Degree-of-Freedom Fully Coupled Dynamical Plant Models: Theory and Experimental Evaluation

This paper reports a comparative experimental evaluation of one model-free proportional derivative (PD) three degree-of-freedom (DOF) controller and two model-based three-DOF controllers designed to enable low-speed, neutrally buoyant, and fully actuated underwater vehicles to perform trajectory tracking in the X, Y, and heading DOFs. We show the model-free PD controller provides locally asymptotically stable set-point regulation. We show the model-based controllers provide locally asymptotically stable trajectory tracking. The reported controllers were experimentally evaluated on the Johns Hopkins University remotely operated vehicle. We report the model-based controller's mean absolute position and velocity tracking error is significantly smaller than the model-free PD controller for coupled maneuvers. We report the fixed, model-based controllers performed best using a parameter model including fully parameterized quadratic drag model parameters, and that the choice of parameter model has a significant effect on the performance of the model-based controllers during disparate experimental trials.