Design and Control of a Novel Steer-by-Wire System for Marine Vessels

This paper proposes a novel steer-by-wire (SBW) system for marine vessels as a viable alternative to conventional hydraulic steering systems. By replacing mechanical linkages, the proposed SBW system enhances responsiveness, reduces complexity, and minimizes operator fatigue. Designed with a power transmission mechanism suited to maritime environments, it features a modular architecture that allows for seamless integration into existing vessels. Onboard experimental studies quantify the forces required for steering, establishing design criteria for the SBW system, while a disturbance observer (DOB)-based velocity controller improves tracking performance under unpredictable maritime conditions. Moreover, a sensorless admittance control strategy enables steering-feel rendering without the need for additional force sensors, thereby simplifying the overall design. Analyses of stiffness and damping characteristics further reveal that individual and combined tuning of these coefficients allows for customizable steering feel tailored to diverse operator requirements.