Optimization of a Hydrofoiling International Moth design and performance investigations with a 6 DOF dynamic model

Hydrofoiling boats represent the cutting-edge of the world of sailing. Their ability of “flying over the water” makes them one of the most fascinating challenges for designers. The increasing complexity results in the need to fnd trade-offs across the multiple specialist areas involved, in order to achieve a successful project. Hence the importance in the development of design tools capable of “foreseeing the future”. This thesis work aims to contribute to all design stages, from the preliminary to the more detailed, of an International Moth. At frst, the high-level requirements are identifed, imposed by the sailor’s needs, manufacturing’s limits and performance. Therefore, an optimization tool is implemented, by exploiting global and local optimization algorithms, aiming to determine the best boat’s confguration capable to be compliant with requirements. Considerable emphasis is placed on the stability concepts, by analysis both static and dynamic aspects through the small perturbation theories. The need to move a step towards the reality and to simulate the performance of the resulting design, leads to the development of a 6 DOF dynamic model. The model allows for sailor-boat interactions and stability assessments, as well as manoeuvres simulations. Sailor’s movements and adjustments are reproduced by means of controllers on sail, rudder and rudder-foil. An in-depth study of the main foil control system is provided, highlighting its performance and its crucial role in ensuring a stable flight.