Fluttering skid phenomena in high speed marine vehicles

In a recent project, named SEALAB, a novel marine vehicle has been developed. Its main characteristic is the presence of special skid surfaces surfing over rough water. A suspension system controls the vertical motion of the skid, softening the sequential impacts and vibrations induced by the water, similarly to a wheeled vehicle in off-road trials. The hull-skid-suspension set is modeled by prototypical equations. The system undergoes special regimes when the vessel speed at sea is varied. In particular, for some combinations of the forward speed and sea-state, the skid still maintains the contact with the water. In other navigation conditions the skid indeed jumps out the water with a complete different average transmitted force and vibration characteristics of the hull. This paper presents a theory that outlines these phenomena identifying conditions that lead to the jumping skid condition.