A system includes a first jacket that contains seawater and a first tank storing a first fluid under pressure. A second jacket contains seawater and a second tank storing a second fluid under pressure. An actuator cylinder defines a space that receives the fluids from the first and second tanks. The actuator cylinder includes an actuator piston that divides the space into a first volume for the first fluid and a second volume for the second fluid. A hydraulic cylinder includes a hydraulic piston configured to move and change an amount of hydraulic fluid in the hydraulic cylinder, wherein the hydraulic piston is fixedly coupled to the actuator piston. A buoyancy plug changes a position in connection with the amount of the hydraulic fluid in the hydraulic cylinder, wherein the position of the buoyancy plug affects a buoyancy of a vehicle.

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.

The present invention discloses a system for measuring the mechanical properties of sea floor sediments at full ocean depth. The system includes an overwater monitoring unit and an underwater measurement device, where the underwater measurement device includes an observation platform and a measuring mechanism; the observation platform includes a frame-type body and a floating body, a wing panel, a floating ball cabin, a leveling mechanism, a counterweight, and a release mechanism mounted on the frame-type body; the floating ball cabin seals a circuit system; the leveling mechanism adjusts the underwater measurement device horizontally on the sea floor when the frame-type body reaches the sea floor; the release mechanism discards the counterweight for recovery of the unit after the underwater measurement device completes the underwater operation; the measuring mechanism includes at least one of a cone penetration measuring mechanism, a spherical penetration measuring mechanism, and a vane shear measuring mechanism, or a sampling mechanism.

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.

An electric power transmission device transmits electric power to an electric power reception device including an electric power reception coil in water. The electric power transmission device includes one or more transmission coils which include an electric power transmission coil configured to transmit electric power to the electric power reception coil via a magnetic field, an electric power transmitter, configured to transmit AC power to the electric power transmission coil, a capacitor which is connected to the transmission coil and forms a resonance circuit which resonates with the transmission coil, a first tubular member which is waterproof and seals a periphery of the transmission coil, a second tubular member which surrounds the first tubular member and includes a plurality of holes, and an adjuster, configured to adjust an amount of air in a gap between the first tubular member and the second tubular member.

This invention is directed to a column floater with extended cylinder and a ring buoy-group, which comprises an upright buoy at a water surface, an extended cylinder, a positioning system and a topsides. The top of the upright buoy is above the water surface and a moonpool is either set or not in the center of the upright buoy through the top to the bottom. The extended cylinder, connecting to the bottom of the upright buoy and extending downwards, includes two types of fixed and sliding to form a column floater with fixed extended cylinder and a column floater with sliding extended cylinder respectively. The positioning system is one or two combined of mooring system and DP system. The column floater with extended cylinder is a new type floating platform with multi-purpose, combining advantages of the spar platform and the current cylindrical FPSO, high performance, safety and reliability.

Floating construction comprising: a flotation base, comprising at least one essentially hollow body selectively fillable with ballast, where the maximum horizontal dimension of the flotation base is greater than the maximum vertical dimension of the floating base; a building supported by said flotation base preferably comprising a telescopic tower; downward impelling means; and at least three retaining cables the corresponding upper ends of which are attached to said flotation base, preferably in peripheral positions of the flotation base, and the corresponding lower ends of which are attached to said downward impelling means, such that said retaining cables are taut and apply a downward force on said flotation base that increases the stability thereof. And the installation method for this floating construction.

A self-propelled offshore installation vessel (1) operates at an offshore position and has at least one water pump (27) being operable to pump water from a water inlet opening (22) to a water outlet opening (25) via water conduit pipes (24). The water system can eject water out through the water outlet opening(s), whereby the ejected water interacts with the waves to dampen waves in an affected area (35) of the sea at the self-propelled offshore installation vessel (1).

A tether control system for an inspection vehicle operable in a housing having a liquid medium is disclosed in the present application. The tether system includes a tether connected between the inspection vehicle and an electronic controller. A controllable buoyancy system associated with the tether is operable for moving the tether in a desired location. The controllable buoyancy system includes one or more floating bodies having a propulsion system and one or more buoyant elements having variable buoyancy capabilities.

An apparatus for towing geophysical sources includes a housing; a first geophysical source disposed in the housing so that the first geophysical source is partially exposed to a surrounding environment; and a plurality of ballast tanks coupled to the housing and configured to at least one of: change a buoyancy of the source towing system; and shift a center of mass of the source towing system. A method of towing a geophysical source includes towing a source towing system through a body of water at a towing depth; and operating a plurality of ballast tanks of the source towing system to at least one of: change a buoyancy of the source towing system; and shift a center of mass of the source towing system.