Rudder roll stabilisation-an improved control law

Although rudder roll stabilisation was proposed more than two decades ago, the control laws proposed thus far have either required high slew rate rudders, or can only provide effective stabilisation over a narrow range of sea conditions. This paper proposes a synthesis of existing control laws of very different types that exploits the advantages of both these types. Thus good stabilisation can be achieved over a wide range of sea conditions without requiring a fast and expensive rudder. A description of an implementation of this control law within a practical rudder roll controller is also given