Cascade control system of fin stabilizers

The paper presents a concept of roll stabilization control system making use of an additional feedback loop. The task of the system is to compare the measured lift force with that determined by the controller, and minimize the possible difference by adjusting the turn angle for every fin separately. A PDD² controller has been selected as a main regulator. A method for obtaining the settings is based on the theory of linear systems, and it requires knowledge of parameters of the assumed model. To determine those parameters the relay feedback test was used.