Control of the wave induced vibrations in Air Cushion Catamarans

A well known limit of air cushion catamarans is the so called "cobblestone effect", a resonance phenomenon, which is due to the interaction between the ship body and the air cushion dynamics, excited by the incoming waves. The problem of designing a Ride Control System for the attenuation of the wave induced vertical accelerations of a Surface Effect Ship (SES) is considered. It is shown that the damping of two basic resonant modes can be achieved by two independent control loops. Such a decoupled control scheme exploits the intrinsic orthogonality of the two oscillation phenomena.