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Nowadays, more than in the past, marine industries are paying increasing attention to the environmental impact of ships and vessels. Several solutions have been studied and adopted with the final aim of reducing the exhaust gas emissions, mainly acting on the fuel consumption reduction. Within this scenario, the aim of this article is to investigate the energy performance and the fuel saving potential when employing a magnetic continuously variable transmission in a marine propulsion system. Such magnetic continuously variable transmission, considered among other possible continuously variable transmission designs since its torque capabilities are perfectly suitable for the application at hand, is employed in order to optimize the overall propulsion efficiency through an appropriate optimal variation of the reduction ratio as a function of the propeller loads. A secondary benefit, although not less important, is that the magnetic continuously variable transmission is an oil-free transmission that consequently offers a lower environmental impact as compared to traditional lubricated gearboxes. Owing to these considerations, in the article, the magnetic continuously variable transmission size is first selected on the basis of a simplified static model of the vessel. Subsequently, a dynamic mathematical model representing the overall drivetrain dynamic of the propulsion plant is developed, with the purpose of simulating the transmission behaviour during fast ship manoeuvres. Then, in order to test the effectiveness of the proposed design, a trawler is selected as a case study. This particular ship type has been chosen as it provides a variegated operative profile in terms of speed and required thrust, thus being a representative case of those ships in which a continuously variable transmission installation could effectively provide practical benefits. A quantitative analysis of the plant efficiency is finally provided and critically discussed.

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The future autonomous ships will be operating in an environment where different autonomous and nonautonomous vessels with different characteristics exist. These vessels are owned by different parties and each uses its owned unique approaches for guidance and navigation. The Collaborative Autonomous Shipping Experiment(CASE) aims at emulating such an environment and also stimulating the move of automatic ship control algorithms towards practice by bringing together different institutes researching on autonomous vessels under an umbrella to experiment with collective sailing in inland waterways. In this paper, the experiments of CASE 2020 are explained, the characteristics of different participating vessels are discussed and some of the control and perception algorithms that are planned to be used at CASE 2020 are presented. CASE 2020 will be held in parallel to iSCSS 2020 at Delft University of Technology, the Netherlands.

This paper aims to present a novel approach to design a dynamic positioning system by using a dynamic model based-design approach. The proposed study has been performed to both develop and preliminarily test the control logic that should be implemented on a model scale vessel. Indeed, the proposed tool has been designed for a fully actuated tug vessel equipped with two azimuthal thrusters and one bow-thruster, emulated in behaviour with a dynamic simulator. Thanks to the model actuation, it was possible to design a unique, optimised allocation logic able to fulfil both open-loop and closed-loop commands, sufficiently proved and tuned before the installation onboard. Moreover, a thorough comparison between different design methods, static and dynamic performance evaluation has been carried out. Two different operational modes are tested, and the results are presented: joystick and station keeping.