UC San Diego

The purpose of this study is to merge my on the job marine experience and the control knowledge gathered throughout my studies at University of California San Diego into a practical control design. This thesis creates a Dynamic Positioning (DP) control loop for a supply vessel which utilizes two azimuthal thrusters as actuators. The control loop is designed to also account for external environmental disturbances and sensor measurement noise. The control loop is accomplished using modern control theory which makes use of known vessel dynamics and assumptions associated with the environment and sensor measurement variances. During this thesis research and design period, a testing platform for the control loop was required. Without the ability to retrofit a physical vessel with the proposed azimuthal thrusters it was determined that a simulation model would be required and was designed and implemented in Matlab Simulink to allow for control loop testing and validation. This simulation model is presented as part of the thesis research and design flow as it was a required element of the design and encompasses the knowledge acquired in my marine work and during my period at UCSD. Control loop performance results were obtained through testing on the generated simulation model. These results allowed for validation and optimization during the design phases of the vessel control loop. The principal conclusions were that the simulation model provided sufficient dynamics to properly execute the required tests to the control loop and that the implemented control loop was capable of operating within the determined parameters set forth in the design validation testing