Active Motion Control of High-Speed Hydrofoil Vessels by State-Space Methods

Hydrofoil ships cruising at high speeds often operate in rough weather conditions and hence experience uncomfortable or even unsafe motions without the use of some form of motion control. The research described here concerns an active motion control mechanism for high-speed hydrofoil vessels, aiming at the significant reduction of the vessel motions in regular and random waves. The seakeeping equations of motion are cast into a linear state-space form leading to a linear-quadratic optimal controller shown to attenuate the vessel motion responses significantly. The deterministic control laws designed in the present study are found to perform satisfactorily both in monochromatic and random waves for high-speed vessels supported by hydrofoils and buoyancy.