Abstract: A gyroscopic boat roll stabilizer for a boat comprises a gimbal, having a gimbal axis, an enclosure mounted to the gimbal and configured to precess about a gimbal axis, a flywheel assembly rotatably mounted inside the enclosure for generating a torque that is applied to counter a rolling motion of the boat, and a braking system for controlling precession of the enclosure.

Abstract: A gyro stabilizer includes a rotor arranged to rotate about a spin axis, and a stator, wherein the rotor and the stator include rotor and stator assemblies, respectively. The rotor assembly is arranged radially outside the stator assembly with respect to the spin axis, wherein the rotor and/or stator assemblies include magnets with magnetic axis in the direction of the spin axis.

Abstract: A gyroscopic roll stabilizer includes an enclosure, a flywheel assembly, and a motor. The enclosure is mounted to a gimbal for rotation about a gimbal axis and configured to maintain a below-ambient pressure. The flywheel assembly is rotatably mounted inside the enclosure for rotation about a flywheel axis. The flywheel assembly includes a flywheel and flywheel shaft. The flywheel shaft has a first end and an opposite second end; a first cavity formed in the first end and facing away from the second end; and a second cavity formed in the second end and facing away from the first end. The flywheel shaft has a longitudinal passage connecting the first cavity and the second cavity. This longitudinal passage may be used for inspection of one of the cavities and/or an associated seal, from the direction of the other cavity. Related methods are also disclosed.

Abstract: A gyroscopic roll stabilizer for a boat includes an enclosure mounted to a gimbal for rotation about a gimbal axis and configured to maintain a below-ambient pressure, and a flywheel assembly including a flywheel and flywheel shaft, with the flywheel assembly rotatably mounted inside the enclosure for rotation about a flywheel axis. The gyroscopic roll stabilizer also includes a motor operative to rotate the flywheel assembly and disposed inside the enclosure. A motor cooling circuit is configured to transfer heat away from the motor. The motor cooling circuit has a closed fluid pathway for recirculating cooling fluid therein. The fluid pathway includes a fluid channel jointly defined by the motor and the enclosure and having the cooling fluid therein. The gyroscopic roll stabilizer is configured to transfer heat away from the motor to the cooling fluid. Related methods are also disclosed.

Abstract: A stability controller includes a machine learning engine that outputs stabilizer settings to several on-board stabilizer systems of a vessel based on various inputs. The machine learning engine is first trained based on human selections of stabilizer system settings, and then, once suitably trained, the stability controller can be used to optimize the use and operation of the stabilizer systems as conditions change, based on a quantity or stability quality that the vessel operator desires to optimize.

Abstract: Disclosed herein are embodiments of an offshore drilling rig comprising: a drill floor (107) defining a well center (123); a hoisting system configured to advance a tubular string (128) downwards through the well center (123) and to the seafloor (124) and to apply a lifting force to a tubular string (128) extending through the well center (123) and to the seafloor (124), the lifting force being large enough to support at least a major part of an apparent weight of the tubular string (128); and an anti-recoil system (218) configured to cause, in case of a sudden reduction of a load suspended from the drilling rig, the hoisting system to raise the tubular string (128) while preventing damage to the hoisting system.

Abstract: 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.

Abstract: An attitude control system includes one or more control moment gyro pairs, with gyros of individual of the pairs being counter-rotated to rotate the rotation axes of flywheels of the gyros of a gyro pair in opposite direction. The flywheels of a gyro pair may be in paddle configuration, with the rotation axes of the flywheels rotating in the counter-rotation through separate planes as the gyros are rotated. The rotation of the gyros of a gyro pair may be accomplished by coupling both of the gyros to a servo motor with suitable coupling gears, or by using independent servos for each gyro. The counter-rotation of gyros of an individual pair produces a resultant torque about a fixed global axis, such as the axis of a flight vehicle of which the attitude control system is a part. Further control may be accomplished for example by varying rotation speeds of the flywheels.

Abstract: Controlling marine vessel: obtaining motion data related to the marine vessel; obtaining an operation state related to one or more apparatuses exerting force from the marine vessel to ambient water; detecting a disturbance in one or more degrees of freedom affecting the marine vessel based on the motion data; and determining control data for the one or more apparatuses exerting force to attenuate the detected disturbance.

Abstract: Various autonomous aquatic herbicide application vessels are described. In one embodiment, a system for aquatic herbicide application includes an aquatic vessel, a propulsion system to propel the aquatic vessel over a body of water, a holding container to hold a substance, a substance applicator to apply the substance to the body of water, and a controller. The controller can include a control processor configured to navigate the aquatic vessel using the propulsion system and apply the substance to the body of water using the substance applicator. According to one embodiment, the system includes a global positioning system to determine a geographic location of the system and a memory to store a route for application of the substance in the body of water. Further, the controller is configured to autonomously control the propulsion system to track the route based on changes in the geographic location of the system over time.

Abstract: A floating device having active stabilization and a method for actively stabilizing a floating device employs a floating device that operates underwater and which may be tethered to the floor of the body of water. The floating device having active stabilization includes an internal sensor assembly which measures angular velocity and generates a real time output corresponding to a measured angular velocity and a counter-rotation assembly which generates in real time mechanical energy in the form of rotation in response to the real time output of the sensor assembly that causes a counter-rotation torque on the device body that opposes the measured angular velocity. The counter-rotation torque may be imparted by accelerating a flywheel as a reaction wheel in the opposite direction of the desired counter-rotation torque, thereby achieving stability of the device body in the form of minimizing rotation.

Abstract: The subject invention is a design of marine cargo vessel with added mechanical equipment specifically designed to minimize dangerous motions of the vessel induced by high waves while the vessel is being loaded or unloaded from fixed platforms (bottom supported or tension leg) at sea or on inland waters. The vessel uses three means of reduction of such induced motions, which have not before been combined for this purpose. These are a small water plane area multiple hull design, rapid ballasting while loading and unloading, and vertical thrusters.

Abstract: A system and a method to warn a ship crew of potential violent motions in the immediate near future for the oceangoing vessel when operating in seas. Violent ship motions not only discomfort ship crews, damage cargos and ship structures, but also pose potential capsizing risk to ships. The system includes motion sensors; computer hardware and software; and warning devices. The sensors measure the ship roll, pitch, yaw, and rudder motions. The time histories of these motions are stored in the hardware and constantly analyzed using Finite Fourier Transform by Fast Fourier Transform (FFT) to detect the nonlinear inertial coupling effect which is newly discovered by the inventor and believed to be the root cause leading to violent motions and capsizing.

Abstract: Disclosed herein are embodiments of an offshore drilling rig comprising: a drill floor (107) defining a well center (123); a hoisting system configured to advance a tubular string (128) downwards through the well center (123) and to the seafloor (124) and to apply a lifting force to a tubular string (128) extending through the well center (123) and to the seafloor (124), the lifting force being large enough to support at least a major part of an apparent weight of the tubular string (128); and an anti-recoil system (218) configured to cause, in case of a sudden reduction of a load suspended from the drilling rig, the hoisting system to raise the tubular string (128) while preventing damage to the hoisting system.

Abstract: Wakeboat hull control systems are provided that can include a first accelerometer operatively associated with the hull of the wakeboat to measure the acceleration of the hull along a first axis; a second accelerometer operatively associated with the hull of the wakeboat to measure the acceleration of the hull along a second axis, the first axis being non-parallel to the second axis; and processing circuitry calculating the rotation of the hull of the wakeboat about a third axis based on the acquired measurements. Wakeboat hull control methods are provided that can include using the processing circuitry to calculate the rotation of the hull of the wakeboat about a third axis based on the acquired measurements.

Abstract: A stabilizer device for a watercraft with a hull. The stabilizer device includes a fin blade with a fin base, a fin tip, a leading edge, and a trailing edge, wherein a blade forward direction (fb) is defined from the trailing edge to the leading edge at the fin base, wherein the fin blade comprises a first fin connection element connected to the fin base in a first connection point a hull element arranged to be fixed to the hull with a hull forward direction (fh) in a forward direction of the hull, and a fin blade displacement portion connected to the first fin connection element and the hull element and arranged for displacing the first fin connection point a first displacement, in parallel with a lower surface of the hull, and perpendicular to the hull forward direction (fh).

Abstract: An AC motor hydraulic system which utilizes a plurality of centrally controlled AC servo motor driven hydraulic pumps with integrated reservoirs to effectuate rotation of a plurality of stabilizer fins mounted about a vessel to automatically counter unwanted movement of a vessel.

Abstract: The disclosed technology is directed to a floating system capable of facilitating transmitting underwater signals (e.g., images captured underwater) to an abovewater device. The system includes a first housing, a second housing, an antenna, a signal emitter, a signal converter, and a signal interface. The first and second housings collectively form an enclosed space. The antenna is vertically positioned on the top surface of the first main body. The signal emitter and the signal converter are positioned in the enclosed space and coupled to the antenna. The signal interface is positioned on the bottom surface of the second housing and coupled to the converter. A user can connect an underwater camera to the signal interface and transmit images captured underwater to another abovewater device through the floating system.

Abstract: A life raft may include a base having a first side and a second side. The life raft may also include a first canopy coupled to the first side of the base and configured to extend across the first side of the base to form a first chamber defined between the first side of the base and the first canopy. The life raft may further include a second canopy coupled to the second side of the base and configured to extend across the second side of the base to form a second chamber defined between the second side of the base and the second canopy. At least one of the first canopy and the second canopy may define a first plurality of fill ports. The at least one of the first canopy and the second canopy is a bottom canopy configured to extend below the life raft.

Abstract: A motion control system for a ship has one or more sensors generating sea condition data and at least one ship control system. Analyzer software receives the sea condition data and predicts a sea condition event. Calculator software calculates one or more commands in preparation for the sea condition event. Interface software communicates the one or more commands to the at least one ship control system and the at least one ship control system implements a command in advance of the event. The at least one ship control system may comprise a ride control system having one or more motion control devices. The at least one ship control system may also comprise an auto pilot system.

Abstract: A method for controlling a rotation damper operating according to the gyroscopic principle for a motor vehicle, wherein the rotation damper includes a flywheel, which is driven by a drive and rotating about a rotation axis with an angular velocity ??, which is cardanically mounted via a first bearing element and via a second bearing element, wherein the flywheel is rotatably mounted on a first bearing element and at a rotation angle ?, and the first bearing element is rotatably mounted on a second bearing means about a first axis that is oriented orthogonally to the rotation axis of the flywheel, and the second bearing element is rotatably mounted at a second rotational angle (?).

Abstract: Disclosed herein is a motorized kayak comprising: a hull; a hatch; a motor; a pump; a controller; and one or more batteries; wherein the hull and hatch create a water and air tight seal and the position of the batteries is adjustable to change the center of gravity.

Abstract: The present invention provides a method for removing copper and aluminum from an electrode material and a process for recycling electrode material from waste lithium-ion batteries. The method for removing copper and aluminum from the electrode material comprises: subjecting the electrode material containing electrode active material, copper and aluminum to reaction with an aqueous solution, wherein the aqueous solution has a pH value of higher than 10, and comprises base, oxidizing agent and complexing agent. The process for recycling electrode material from waste lithium-ion batteries comprises: a) harvesting an electrode material containing electrode active material, copper and aluminum from waste lithium-ion batteries; b) removing copper and aluminum from the electrode material according to the foresaid method; and c) further purifying and regenerating the electrode active material for reuse in new lithium-ion batteries.

Abstract: A stabilizer (10) includes a base (20) fixed on a motion reduction target (1); a gimbal (40) supported by the base to be rotatable around a first axis (RA); a damper mechanism (30) disposed to damp a relative rotary motion of the gimbal (40) to the base (20); a flywheel (50) disposed to be rotatable around a second axis (RB) orthogonal to the first axis (RA). The damper mechanism (30) is a passive-type damper mechanism. A first value (D1) of a damping coefficient (D) of the damper mechanism (30) when an angular velocity of the gimbal (40) is a first angular velocity is larger than a second value (D2) of the damping coefficient (D) of the damper mechanism (30) when the angular velocity of the gimbal (40) is a second angular velocity smaller than the first angular velocity.

Abstract: A semi-submersible structure with buoyant vertical columns and a buoyant pontoon. Unlike the typical semi-submersible where the pontoons are attached directly between the columns, the pontoon of the invention encircles the columns and is arranged outside of the columns. The pontoon encircling the columns simplifies construction and attachment of the pontoon and columns and improves the heave characteristics of the structure.

Abstract: The invention concerns a method for transferring a load between a target position on board a vessel (40) and an outboard position outboard said vessel. The invention further concerns a motion compensation device (1) applying the method. In the method the load is being transferred by a crane (30) carried by a motion compensation device arranged on board the vessel. The motion compensation device comprises a carrier frame (2), a base (3) and an actuator system (8, 9) for moving the carrier frame with respect to the base; the base being fixed to the vessel and the crane being carried by the carrier frame. During picking up a load from the vessel or placing a load on the vessel, the actuator system is being driven in an on board mode such that the carrier frame is being compensated for x-axis rotational movement and y-axis rotational movement of the vessel, and follows, viewed in the vertical direction, the vertical movement of the target location.

Abstract: System for stabilizing an offshore horizontal axis wind turbine having a tower, the system comprising sensors for generating signals representing detected movements of the tower, and gyroscopes. Each gyroscope has a spinning axis, an input axis and an output axis, and a flywheel rotatable about the spinning axis. The system further comprises an actuator for each gyroscope, said actuator being arranged with its related gyroscope in such a way that this actuator can apply a torque about the input axis of the gyroscope. The system also comprises a control unit for receiving the signals representing detected movements of the tower, and for providing the actuator with suitable control signals for said actuator to apply a torque about the related gyroscope input axis, said torque about the input axis producing a torque about the output axis of the same gyroscope that at least partly dampens the detected movements of the tower.

Abstract: The present invention includes: first and second tanks and each configured to store a fluid containing fine powder; a communication pipe through which the first and second tanks and communicate with each other; and a transfer portion configured to transfer the fluid stored in a desired one of the first and second tanks to the other tank. Each of the tanks and includes a first chamber and a second chamber that are separated by a deformable dividing wall. Each of the first chambers stores an incompressible fluid, and each of the second chambers stores the fluid having higher specific gravity and viscosity than the incompressible fluid. The second chambers of the first and second tanks communicate with each other through the communication pipe. When the incompressible fluid is supplied to the desired first chamber, the transfer portion can discharge the incompressible fluid from the other first chamber.

Abstract: A rolling motion reducing apparatus includes a flywheel, a gimbal, a gimbal supporting section, a damper and a lock mechanism. The gimbal rotatably supports the flywheel. The gimbal supporting section supports the gimbal 11 through a gimbal shaft such that the gimbal can rotate. The damper 13 brakes a rotational motion of the gimbal. The lock mechanism locks a rotational motion of the gimbal.

Abstract: The method consists of: A step of estimating a direction (D) of propagation of the swell and a propagation speed of the swell, a step of measuring the development of a characteristic value of the swell at at least one measuring point (P) upstream of the ship in the direction of propagation (D) by periodically measuring the value, a step of detecting a lull in the swell at the measuring point (P) using a measurement of the development of the characteristic value, including a measurement of a duration of a lull detected, and if a lull in the swell is detected at the measuring point (P): a step of calculating a time interval between the detection of the lull in the swell at the detected measurement point (P) and a moment in which the lull affects the movement of the ship (N), carried out, in particular, depending on the estimated speed of propagation of the swell.

Abstract: A vessel has a hull, a contact area at the hull near keel level for attaching to a structure, a lifting device and a lifting cable attached thereto and extending along a heave compensating member. The lifting cable extends along a substantially vertical lifting trajectory to a connect position below keel level. The heave compensating member includes a guide element for guiding the lifting cable and which is connected to a displacement device. The heave compensating member includes a compensator arm with a pivot end pivotally connected to a pivot point on the vessel at a predetermined transverse distance from the lifting trajectory, the cable guide element being attached to a free end of the compensator arm at or near the lifting trajectory, guiding the lifting cable in the direction of the pivot point, the arm being at or near the free end connected to the displacement device.

Abstract: This invention relates to a method and a device for averting and damping rolling of an engine-driven marine vessel with propeller propulsion. The proposed method recognizes the fact that the speed controller of a ship responds to heel angle variations by propeller speed adjustments. A speed controller is reading such propeller moment change as speed variations to be corrected. By the recurrence of this process, the result is amplifying small rolling effects to a critical rolling. Further elements contribute to this process, such as the propeller side effects ship's hull contact with the sea, waves or winds. However, by suppressing the interaction between heel angle variations and the speed controller, the rolling of a ship can be effectively reduced and averted. The proposed method, by suppressing the cause of the critical rolling, reduces rolling, fuel consumption and maintenance of the ship's propulsion engines.

Abstract: A suspension system for passenger modules used with high-speed boats, the suspension system including a shock absorbing assembly, for supporting the passenger module relative to the vessel. The passenger module is attached to the vessel via an assembly of pivoting spars in which the vessel attachment locations are spaced athwart a greater distance than the passenger module attachment locations. The suspension system may include means for resisting relative lateral movement (e.g. a panhard rod or a Watt's linkage) and for attenuating motion associated with pitch and roll.

Abstract: The disclosure reduces vertical movement of a floating offshore platform by including a centralized open keel plate coupled to the hull that allows water below and above the keel plate. As the floating platform moves vertically, the keel plate separates the water and causes drag on the platform. The water moving vertically with the plate also increases the dynamic mass. The drag results in less vertical movement of the offshore platform without the need to extend legs of the platform to gain an equivalent reduction in vertical movement. The added dynamic mass increases the natural period of the vertical motion away from the wave excitation period to minimize the wave driven motion. The keel plate generally is above or at the same level of the keel, and therefore would not reduce the clearance between the seabed and the keel of the hull at the quayside.

Abstract: A vessel stabilizer control system (12) includes a sensor fault detection means (16) which senses the availability of sensing signals from a gyrostabilizer precession motion sensor (10) and a vessel roll motion sensor (14). The control system (12) controls the action of a gyro-actuator (8) which is mechanically coupled to a gyrostabilizer (4). The benefit of employing fault sensing of the sensors providing the process control variables is that the sensed number of available process control variables (or sensors) can be used to activate a tiered system of control modes. Each tiered control mode is designed to utilize the available process control variables to ensure safe and effective operation of the gyrostabilizer (4) that is tolerant of sensor faults and loss of power supply. A control mode selector (18) is provided for selecting the appropriate control mode based on the number of available process control variables.

Abstract: A gyrostabilizer control system and method for stabilizing marine vessel motion based on precession information only. The control system employs an Automatic Gain Control (AGC) precession controller (60). This system operates with a gain factor that is always being gradually minimized so as to let the gyro flywheel (12) develop as much precession as possible—the higher the precession, the higher the roll stabilizing moment. This continuous gain change provides adaptation to changes in sea state and sailing conditions. The system effectively predicts the likelihood of maximum precession being reached. Should this event be detected, then the gain is rapidly increased so as to provide a breaking precession torque. Once the event has passed, the system again attempts to gradually decrease the gain.

Abstract: A heave compensation and tensioning apparatus for use on a floating vessel during “locked-to-bottom” operations is provided. The apparatus includes a pair of hydraulic cylinders that are fixed to a lower section of a frame. Respective free ends of piston rods of the hydraulic cylinders are operatively associated with an upper section of the frame. A pair of accumulators are in communication with pressure vessels and the cylinders using a pneumatic fluid line and a primary hydraulic fluid line, respectively. A control valve assembly allows the piston rods to retract or extend in response to, and to compensate for, heave of the floating vessel. An isolation valve can hydraulically lock the piston rods. In this way, the heave compensation and tensioning apparatus forms a rigid link and can be employed as a secondary or back-up heave compensator for a primary heave compensator.

Abstract: A method for maintaining the heading of a ship during movements caused by waves approaching the ship from a stern direction by activating a control surface in a bow of the ship such that the control surface converts a water flow along the bow into a lateral force that opposes roll, yaw, or heeling movements and course changes.

Abstract: A ship for use at high speed and/or heavy seas having a single long and slender hull, a sharp bow and the aft end of the hull has a flat or slightly V-shaped bottom with at least one aft rudder, and at least one propeller or water jet for propulsion whereby the foreship has a draught that is equal or more than the draught of the aft end. The bow has a control surface that converts the water flow along the forward moving ship into an adjustable lateral force.

Abstract: The present invention relates to a vessel comprising:-a hull,-a support structure connected to said hull, the support structure configured for supporting the mass, the support structure being constructed to allow the mass to make a back and forth movement relative to said hull along a trajectory between opposite ends of said trajectory,-a damping device configured to dampen the movement of the mass relative to said hull. The present invention also relates to a method for damping the movements of a vessel or of a mass.

Abstract: A small boat dynamic roll stabilizer. The stabilizer includes two or more pairs of spaced-apart flexible bellows or air bags to receive and support a boat hull during passenger loading and unloading. Dynamic pitch is limited or even stopped for the boat hull by maintaining each of the bellows, which each has a contact surface contacting a portion of the hull from below (within the water), at an internal pressure great enough to support dynamic loading of the boat hull while allowing the water to support the hull's static load. A pressure chamber is provided that has its interior volume linked via ducting or piping with the bellows, and a controller uses a feedback loop to operate an actuator to move a piston within the pressure chamber to maintain the pressure of the chamber and linked bellows as the loading of the boat hull dynamically varies during loading and unloading.

Abstract: The invention is related to a method and system for measuring motions of a moving, essentially rigid, floating (elongated) body such as a boat, yacht or vessel using two motion detectors that are installed near the ends of, or far enough away from each other in the (elongated) floating body. In accordance with the invention the two motion detectors are essentially simultaneously measuring the movements of the floating body.

Abstract: A transportable watercraft stabilization apparatus includes a stability device configured to impart a stabilizing torque to a watercraft when mounted on the watercraft and a transportable containment device containing the stability device therein. The transportable containment device includes a first attachment apparatus for releasably attaching to a transporting means and a second attachment apparatus for releasably attaching to a coupling device onboard a watercraft. Furthermore, the transportable watercraft stabilization apparatus includes a power source configured to provide power to the stability device for generating the stabilizing torque. The watercraft stabilization apparatus is transportable between a first watercraft and a second watercraft for providing on-demand stabilization to the second watercraft.

Abstract: A multi-hulled vessel (10) configured as a trimaran. The multi-hulled vessel (10) comprises a main hull (15) and at least one outer hull (17) to each side of the main hull. The multi-hulled vessel (10) is provided with motion control means (40) for providing damping to wave-induced motion, thereby offering ride control. The motion control means (40) comprises a forward motion damping device (41) disposed adjacent the bow (25) of the main hull (15), and two aft dampening devices (43) disposed one adjacent the stern (33) of each side hull (17). With this arrangement, one of the motion damping devices (41, 43) is located at or near each apex of a notional triangular envelope (44) of the vessel (10). Each motion damping device (41, 43) is configured to resist wave-induced motion of the multi-hulled vessel (10) and thereby provide a damping effect. Each motion damping device (41, 43) may comprise an underwater hydrofoil (45), although other damping arrangements are possible.

Abstract: Provided is an apparatus for reducing the pitching and rolling motion of a vessel, the apparatus including a plurality of buoyancy members spaced apart from each other and vertically slidably mounted on a vessel, a plurality of hydraulic cylinders that are connected to the upper end portions of the respective buoyancy members and receive the locomotive power of the buoyancy members that rise from waves, and a hydraulic connection line provided in such a manner that the hydraulic pressures of the hydraulic cylinders are interconnected, so that the hydraulic pressures, which are generated from the rise of the hydraulic cylinders due to the rise of the buoyancy members located at the peaks of the waves, can be supplied to the hydraulic cylinders located at the troughs of the waves to cause the buoyancy members to fall, thereby increasing the buoyancy of the vessel and restraining the pitching and rolling thereof.

Abstract: Provided is an apparatus for reducing the pitching and rolling motion of a vessel, the apparatus including a plurality of buoyancy members spaced apart from each other and vertically slidably mounted on a vessel, a plurality of hydraulic cylinders that are connected to the upper end portions of the respective buoyancy members and receive the locomotive power of the buoyancy members that rise from waves, and a hydraulic connection line provided in such a manner that the hydraulic pressures of the hydraulic cylinders are interconnected, so that the hydraulic pressures, which are generated from the rise of the hydraulic cylinders due to the rise of the buoyancy members located at the peaks of the waves, can be supplied to the hydraulic cylinders located at the troughs of the waves to cause the buoyancy members to fall, thereby increasing the buoyancy of the vessel and restraining the pitching and rolling thereof.

Abstract: The invention relates to the field of buoyant bodies, and more particularly to an annular buoyant body (1) including a central moonpool (2), configured such that, in water, with swell of a period substantially equal to a natural period of the buoyant body (1) while it is moving with heave motion, vertical forces exerted on the buoyant body (1) by a mass of water oscillating in the central moonpool (2) in phase opposition relative to the swell, compensate at least partially for the vertical excitation forces exerted on the buoyant body (1) by the swell. The invention also relates to a method of at least partially extinguishing heave motion of the buoyant body (1) at a natural period of the buoyant body (1).

Abstract: The present invention is directed to a system including a self supporting riser (SSR) which is connected to a well to provide fluid communication to fossil hydrocarbon reservoirs deep below the seafloor. The SSR is constructed of a plurality of joints comprising regular joints and specialty joints that define the SSR and are selected to optimize the SSR for a well in a specific location. A unique aspect of the invention is further directed to a small vessel subject to high vessel motions that permits a coil tubing/wire line system to be mounted on a stabilizer system mounted on the vessel. The riser extension that connects the vessel to the self supporting riser preferably has a telescopic joint/section that is designed for the heave of the vessel.

Abstract: The invention relates to an arrangement (1) for dynamic control of running trim and list of a boat, said boat having at least one hull (2) with a stern (3), said arrangement (1) having a housing member (9), an interceptor member (5), an actuating means (10), a drive unit (7) operated by a power supply means (8), and a guiding means (22), said guiding means (22) being arranged to guide said interceptor member (5) between a first end position and a second end position, said actuating means (10) being arranged to displace said interceptor member (5) in a movement between said first and second end positions in relation to said housing member (9) by being driven by said drive unit (7), and said housing member (9) fully enclosing said interceptor member (5) in said first end position and partially enclosing said interceptor member (5) in said second end position.

Abstract: A method for controlling a stabilizing fin for anti-roll stabilization of watercraft standing at anchor, comprising the steps of: detecting at least one value identifying roll of the watercraft; estimating the expected oscillation of roll of the watercraft as a function of the value detected; determining a path for the movement of the stabilizing fin as a function of the expected roll; and controlling the movement of the stabilizing fin as a function of the path.