A boat may have a deck and a plurality of pontoons or hulls supporting the deck of the boat. The boat may include a starboard side pontoon, a port side pontoon, and possibly a middle pontoon. A positioning assembly may be provided with one or more of the foregoing pontoons. Each of the positioning assemblies may comprise a link assembly coupling the deck to the starboard side toon, wherein the link assembly is configured to permit pivoting of the starboard side toon relative to the deck from a retracted position, where the starboard side toon is proximate to an underside of the deck, to an extended position, where the starboard side toon is moved further from the underside, and an actuator provided to position the starboard side toon between the retracted position and the extended position. The boat may further include a leveling control system having a controller and a level sensor configured to detect an attitude of the deck, the controller in communication with the actuators and cause actuation of either or both of the actuators to extend or retract the port side toon and/or the starboard side toon based on data received from the level sensor indicative of the deck attitude.

A boat may have a deck and a plurality of pontoons or hulls supporting the deck of the boat. The boat may include a starboard side pontoon, a port side pontoon, and possibly a middle pontoon. A positioning assembly may be provided with one or more of the foregoing pontoons. Each of the positioning assemblies may comprise a link assembly coupling the deck to the starboard side toon, wherein the link assembly is configured to permit pivoting of the starboard side toon relative to the deck from a retracted position, where the starboard side toon is proximate to an underside of the deck, to an extended position, where the starboard side toon is moved further from the underside, and an actuator provided to position the starboard side toon between the retracted position and the extended position. The boat may further include a leveling control system having a controller and a level sensor configured to detect an attitude of the deck, the controller in communication with the actuators and cause actuation of either or both of the actuators to extend or retract the port side toon and/or the starboard side toon based on data received from the level sensor indicative of the deck attitude.

A buoyage for emergency communication and a corresponding rescue method are provided. The buoyage for emergency communication includes: a positioning device, a buoyancy block, a plurality of compression springs, an optical fiber, a reel, a frame, an optical fiber slip ring, a pure iron disk, an optical fiber connector and an oil-filled electromagnet, wherein the positioning device is fixed on a top portion of the buoyancy block, and is configured to emit a position signal of itself when the buoyage returns to a surface of water; the buoyancy block is provided above the frame, wherein the compression springs are provided between the buoyancy block and the frame; the pure iron disk is fixedly on a center of a bottom portion of the buoyancy block. The oil-filled electromagnet is adsorbed to the pure iron disk after being energized to limit a vertical displacement of the buoyancy block.

A buoyage for emergency communication and a corresponding rescue method are provided. The buoyage for emergency communication includes: a positioning device, a buoyancy block, a plurality of compression springs, an optical fiber, a reel, a frame, an optical fiber slip ring, a pure iron disk, an optical fiber connector and an oil-filled electromagnet, wherein the positioning device is fixed on a top portion of the buoyancy block, and is configured to emit a position signal of itself when the buoyage returns to a surface of water; the buoyancy block is provided above the frame, wherein the compression springs are provided between the buoyancy block and the frame; the pure iron disk is fixedly on a center of a bottom portion of the buoyancy block. The oil-filled electromagnet is adsorbed to the pure iron disk after being energized to limit a vertical displacement of the buoyancy block.

A motion absorbing system and method for a structure includes the coupling of a container to a structure. The container has a liquid disposed therein wherein a ullage is defined above a surface of the liquid. An elastic element is positioned in the liquid. The elastic element has a natural frequency tuned to damp motion of the liquid.

A method of stabilising a marine vessel having a stabiliser system is provided. The method comprises receiving real-time vessel motion data from at least one vessel motion sensor, generating one or more primary control signals based on the vessel motion data by means of a primary non-linear control system and generating one or more secondary control signals based on the vessel motion data by means of a secondary linear control system. The method further comprises selecting either the primary control signals or the secondary control signals and transmitting the selected control signals to the vessel stabiliser system.

A method of stabilising a marine vessel having a stabiliser system is provided. The method comprises receiving real-time vessel motion data from at least one vessel motion sensor, generating one or more primary control signals based on the vessel motion data by means of a primary non-linear control system and generating one or more secondary control signals based on the vessel motion data by means of a secondary linear control system. The method further comprises selecting either the primary control signals or the secondary control signals and transmitting the selected control signals to the vessel stabiliser system.

Provided is an electric stabiliser for stabilising a floating structure that includes a track for guiding a mover as a moving stabiliser mass. A direct current (DC) linear motor includes a planar stator that extends along the track and the mover that is adapted to move forwards and backwards along the track as the stabiliser mass. The planar stator includes a polyphase stator winding with winding coils connected. The mover includes permanent motor magnets facing the polyphase stator winding that define mover poles of alternating polarity along the track direction. Two active magnetic bearings is positioned between the track and a main body of the mover for selectively levitating the mover. In use, the active magnetic bearings levitate the mover above the track and the DC linear motor is controlled to move the mover backwards and forwards along the track to dampen a rolling/pitching movement of the floating structure.

A system for maintaining a predetermined roll angle of a hull of a marine vessel, the system comprising: a stabilisation element arranged below the waterline on an outer surface of the hull, a sensor unit providing a first sensor data providing information relating to the movement and/or positioning of the marine vessel, a processing unit 5 receiving the first sensor data and providing a first control output, a control unit receiving the first control output and providing a first control input to the stabilisation element to counteract a rolling movement and/or positioning of the marine vessel.

A system for maintaining a predetermined roll angle of a hull of a marine vessel, the system comprising: a stabilisation element arranged below the waterline on an outer surface of the hull, a sensor unit providing a first sensor data providing information relating to the movement and/or positioning of the marine vessel, a processing unit 5 receiving the first sensor data and providing a first control output, a control unit receiving the first control output and providing a first control input to the stabilisation element to counteract a rolling movement and/or positioning of the marine vessel.