Toward model based dynamic positioning of underwater robotic vehicles

Reports preliminary experimental evaluation of a family of model based trajectory-tracking controllers for the low-speed maneuvering of fully actuated underwater vehicles. First, previously reported studies are briefly reviewed. Second, one linear and five model-based based controllers are presented. Third, preliminary experimental studies are reported. The experimental results corroborate the analytical predictions that the model-based controllers outperform PD control over a wide range of operating conditions. The exactly linearizing model based controller is outperformed by its non-exactly linearizing counterpart. The adaptive controllers are shown to provide reasonable online plant parameter estimates, and velocity and position tracking consistent with theoretical predictions-providing good velocity tracking and, with the appropriate parameter update law, position tracking. To the best of our knowledge, this is the first reported comparative experimental study of this class of model based controllers for underwater vehicles