System identification and dynamic positioning (DP) of ships

Abstract

This report combines system identification and controller tuning for the developing of a DP system for a supply boat vessel. Project objectives include performing literature research about the DP system, implementing a dynamic model of a marine vessel, performing an input experiment design, and in the end, investigating the possibility of identifying a linearized dynamic model and a DP system from the input and output data generated from the vessel model.

Main methods used in this report are literature research, input experiment design, system identification, PRBS, DSR algorithm, PID tuning, programming, simulation and testing.

As conclusions, this paper, with a supply boat as an example, presented an efficient and robust way to build a DP system from a dynamic, discrete, time invariant, linear SSM of the vessel. The algorithms used successfully identified a linearized dynamic model and thereafter a DP system from the input and output data matrices. Applying system identification for the developing of a DP system showed good result. The identified DP system demonstrated satisfactory system performance in all the tested scenarios. It’s also worth to mention that the algorithms used for system identification from the DSR Toolbox showed good user-friendly and reuse characteristics in terms of stableness and generality.