Abstract: A system and method for autonomous vehicle control to minimize energy cost are disclosed. A particular embodiment includes: generating a plurality of potential routings and related vehicle motion control operations for an autonomous vehicle to cause the autonomous vehicle to transit from a current position to a desired destination; generating predicted energy consumption rates for each of the potential routings and related vehicle motion control operations using a vehicle energy consumption model; scoring each of the plurality of potential routings and related vehicle motion control operations based on the corresponding predicted energy consumption rates; selecting one of the plurality of potential routings and related vehicle motion control operations having a score within an acceptable range; and outputting a vehicle motion control output representing the selected one of the plurality of potential routings and related vehicle motion control operations.

Abstract: A field configurable vehicle includes bladders located interior of the vehicle hull walls. One or more of the bladders can be filled with fluids of varying densities to manage the buoyancy, mass properties, and thermal heat dissipation of the vehicle.

Abstract: A system and method for autonomous vehicle control to minimize energy cost are disclosed. A particular embodiment includes: generating a plurality of potential routings and related vehicle motion control operations for an autonomous vehicle to cause the autonomous vehicle to transit from a current position to a desired destination; generating predicted energy consumption rates for each of the potential routings and related vehicle motion control operations using a vehicle energy consumption model; scoring each of the plurality of potential routings and related vehicle motion control operations based on the corresponding predicted energy consumption rates; selecting one of the plurality of potential routings and related vehicle motion control operations having a score within an acceptable range; and outputting a vehicle motion control output representing the selected one of the plurality of potential routings and related vehicle motion control operations.

Abstract: An autonomous deployment system for deploying systems and a method of deploying a seafloor device. The autonomous deployment system includes a release unit, a support frame, a plurality of mats, a hose, a plurality of weighted bands, a gas supply, a waterproof housing, and a timer. The method of deploying a seafloor device includes spooling a plurality of mats in a rolled-up position, each of said plurality of mats comprising a hose, wherein each mat is adjacent to a support frame, submerging the seafloor device in a body of water, releasing the seafloor device from a vessel via a release unit, supplying gas to each hose of the plurality of mats, unfurling each of the plurality of mats from the support frame, sinking the seafloor device to lay on the seafloor. The invention may also include a microbial fuel cell and support weights.

Abstract: A field configurable autonomous vehicle includes modular elements and attachable components. The vehicle can be assembled from these modular elements and components to meet desired mission and performance characteristics without the need to purchase specially designed vehicles for each mission. The vehicle can include a module for buoyancy control.

Abstract: Conventional SCUBA diving equipment is heavy and cumbersome, mainly due to the mass and size of the breathing gas carrier, i.e. the pressure vessel. A preferred pressure vessel for SCUBA diving can be as light as possible and neutrally buoyant at all stages of the dive. To achieve such preferred characteristics, the pressure vessel volume can be adjusted in accordance with the change in its mass. The present invention provides SCUBA systems that provides for the preferred characteristics.

Abstract: Underwater apparatuses and methods of operating underwater apparatuses. The apparatus includes a power source such as an aluminum-water cell. Waste product from the power source may be channeled into various portions of the apparatus to adjust the buoyancy of the apparatus, the center of buoyancy of the apparatus, and/or the trim of the apparatus.

Abstract: A system and method for autonomous vehicle control to minimize energy cost are disclosed. A particular embodiment includes: generating a plurality of potential routings and related vehicle motion control operations for an autonomous vehicle to cause the autonomous vehicle to transit from a current position to a desired destination; generating predicted energy consumption rates for each of the potential routings and related vehicle motion control operations using a vehicle energy consumption model; scoring each of the plurality of potential routings and related vehicle motion control operations based on the corresponding predicted energy consumption rates; selecting one of the plurality of potential routings and related vehicle motion control operations having a score within an acceptable range; and outputting a vehicle motion control output representing the selected one of the plurality of potential routings and related vehicle motion control operations.

Abstract: A method for regulating the buoyancy of an underwater vehicle in such a way that it substantially exhibits a predetermined target buoyancy Fc when it is immersed in a volume of liquid delimited by a first surface and a second surface, along a vertical axis, the method includes starting from an initial buoyancy of the vehicle that keeps the vehicle at the level of the first surface, a first step of modifying the density of the vehicle so that it moves closer to the second surface, the first step being implemented as far as a second step of detecting the crossing, by the vehicle, of a predetermined non-zero threshold on distance with respect to the first surface, along the vertical axis, then a third step of modifying the density of the vehicle until the vehicle exhibits substantially the target buoyancy.

Abstract: A depth selector or current depth provider for use by a variable speed air system. As a depth selector it is preferably in the form of a rotary switch on the user interface for the air system. The rotary switch can have 3 positions for maximum depth selections, such as, without limitation 15, 25, and 65 feet. Other depth values and number of depth selections provided can be used and all are considered within the scope of the disclosure. A microcontroller of the system reads the voltage from the voltage divider created by the rotary switch selection to determine which position the rotary switch is in. The microcontroller uses this information to set the upper and lower pressure limits for the dive.

Abstract: A system for autonomous ocean data collection includes at least one sensor capable of collecting sensor data, at least one transmission device, and at least one computing device comprising one or more hardware processors and memory coupled to the one or more hardware processors, the memory storing one or more instructions which, when executed by the one or more hardware processors, cause the at least one computing device to generate data for transmission based on the sensor data collected by the at least one sensor, and cause the at least one transmission device to transmit the data.

Abstract: A clutch having two stages for applying varied torque between an input shaft and an output shaft includes a clutchpack having input friction plates and output friction plates. The clutch further includes a first spring configured to apply a first pressure to the clutchpack to compress the clutchpack. The clutch further includes a second spring configured to apply a second pressure to the clutchpack to compress the clutchpack. The clutch further includes an engagement nut configured to move in response to rotation of the output shaft relative to the input shaft to compress the second spring in order to increase an amount of the second pressure applied to the clutchpack.

Abstract: 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.

Abstract: A system and method for autonomous vehicle control to minimize energy cost are disclosed. A particular embodiment includes: generating a plurality of potential routings and related vehicle motion control operations for an autonomous vehicle to cause the autonomous vehicle to transit from a current position to a desired destination; generating predicted energy consumption rates for each of the potential routings and related vehicle motion control operations using a vehicle energy consumption model; scoring each of the plurality of potential routings and related vehicle motion control operations based on the corresponding predicted energy consumption rates; selecting one of the plurality of potential routings and related vehicle motion control operations having a score within an acceptable range; and outputting a vehicle motion control output representing the selected one of the plurality of potential routings and related vehicle motion control operations.

Abstract: An unmanned semi-submarine, including a main hull; airfoil buoyancy chambers; an antenna; a radar; a propeller; a rudder; and compartments. The airfoil buoyancy chambers include a front buoyancy chamber and a rear buoyancy chamber. The front buoyancy chamber and the rear airfoil buoyancy chamber are longitudinally distributed on the main hull. The radar and the antenna are disposed on the top end of the front buoyancy chamber. The rudder is disposed on the rear buoyancy chamber. The propeller is disposed at the tail of the main hull to drive the unmanned semi-submarine. The horizontal sections of the front buoyancy chamber and the rear buoyancy chamber are symmetrical airfoil. The compartments include a front equipment compartment, a rear equipment compartment, a control equipment compartment, a battery compartment, and a propelling compartment. The compartments are separated from one another using watertight walls.

Abstract: A method lowers a hollow structure through water and installs that structure at a subsea location. The structure has an internal space containing a ballast material such as sea salt that is substantially denser than water. Upon being lowered with the aid of the ballast material to a subsea destination, the structure is anchored at that destination. Then, water is introduced into the internal space to dissolve, suspend or dilute the ballast material. Thus dissolved, suspended or diluted, the ballast material is evacuated or dispersed from the internal space in a liquid or fluidized form. For example, a solution or suspension of the ballast material can be entrained in a flushing flow of water through and from the internal space. The internal space is then available to perform another, primary function in subsea operation of the structure, for example as a flowline to convey oil or gas.

Abstract: A system for autonomous ocean data collection includes at least one sensor capable of collecting sensor data, at least one transmission device, and at least one computing device comprising one or more hardware processors and memory coupled to the one or more hardware processors, the memory storing one or more instructions which, when executed by the one or more hardware processors, cause the at least one computing device to generate data for transmission based on the sensor data collected by the at least one sensor, and cause the at least one transmission device to transmit the data.

Abstract: A skeg mounts from the stern of a towing vessel and extends below the waterline. A channel in the skeg protects cables for steamers and a source of a seismic system deployed from the vessel. Tow points on the skeg lie below the water's surface and connect to towlines to support the steamers and source. A floatation device supports the source and tows below the water's surface to avoid ice floes. The streamers can have vehicles deployed thereon for controlling a position on the streamer. To facilitate locating the streamers, these vehicles on the streamers can be brought to the surface when clear of ice floes so that GPS readings can be obtained and communicated to a control system. After obtaining readings, the vehicles can be floated back under the surface. Deploying, using, and retrieving the system accounts for ice at the surface in icy regions. In addition, handling the seismic record can account for noise generated by ice impact events.

Abstract: Systems and methods for launching and retrieving payloads in aquatic environments employ a platform that is both floatable and submersible at the discretion of and/or under the control of a user, on which submersible objects to be launched, delivered to a subsea location and/or retrieved (the payload) may be located. The submergible platform has a plurality of sealed and/or sealable buoyancy chambers and at least one low pressure gas storage tank having associated fixtures and valves providing introduction of gas to the buoyancy chambers. One or more buoyant elements may be coupled to the submersible platform to support the platform in a submerged condition. A payload docking system providing secure docking of a payload on the platform deck is also disclosed.

Abstract: An underwater mobile body includes: a communication unit that has a plurality of communicators adopting different communication systems and that performs underwater wireless communication with another device using one of the plurality of communicators; an acquisition unit that acquires information on depth or information varying with depth; and a control unit that controls the communication unit to switch, between the plurality of communicators and based on the acquired information, the one communicator used for underwater wireless communication.

Abstract: An autonomous underwater vehicle (AUV) for recording seismic signals during a marine seismic survey. The AUV includes a body extending along an axis X and having a head portion, a middle portion, and a tail portion, wherein the middle portion is sandwiched between the head portion and the tail portion along the X axis; a cross-section of the middle portion, substantially perpendicular on the X axis, having a triangular-like shape; the head portion including a base portion having the triangular-like shape and configured to match the middle portion; the head portion having a tip that, when projected along the X axis on the base portion, substantially coincides with a centroid of the base portion having the triangular-like shape; and a seismic payload located within the body and configured to record seismic signals.

Abstract: A pod of an ocean current power generation device which is serving as an underwater floating-type underwater device is provided with a ballast tank and an air storage tank. When discharging water from the ballast tank, by opening a water discharge valve and driving a water discharge pump, water inside the ballast tank is discharged to the outside through a water conduit. When supplying water, by opening a water supply valve while the water pressure outside the pod is greater than the water pressure inside the ballast tank, water is made to flow from the outside of the pod through an aperture portion, and into the ballast tank via the water conduit.

Abstract: Embodiments of an autonomous seismic node that can be positioned on the seabed are disclosed. The autonomous seismic node comprises a pressurized node housing substantially surrounded and/or enclosed by a non-pressurized node housing. The seismic node may be substantially rectangular or square shaped for node storage, handling, and deployment. One or more node locks may be coupled to either (or both) of the pressurized node housing or the non-pressurized node housing. The pressurized node housing may be formed as a cast monolithic titanium structure and may be a complex shape with irregularly shaped sides and be asymmetrical. In other embodiments, a non-pressurized housing may substantially enclose other devices or payloads besides a node, such as weights or transponders, and be coupled to a plurality of protrusions.

Abstract: The floating body structure is a floating body structure that supports an object to be supported so that the object to be supported floats in the sea, including a floating body section connected to a base end portion of the object to be supported, wherein the floating body section has a lid body made of steel, an outer pipe made of steel, and an inner pipe made of steel and provided inside the outer pipe, and the floating body section is hermetically sealed by the lid body in a state where at least a portion of a gap formed between an outer wall surface of the inner pipe and an inner wall surface of the outer pipe is filled with concrete or mortar.

Abstract: Embodiments of an autonomous seismic node that can be positioned on the seabed are disclosed. The autonomous seismic node comprises a pressurized node housing substantially surrounded and/or enclosed by a non-pressurized node housing. The seismic node may be substantially rectangular or square shaped for node storage, handling, and deployment. One or more node locks may be coupled to either (or both) of the pressurized node housing or the non-pressurized node housing. The pressurized node housing may be formed as a cast monolithic titanium structure and may be a complex shape with irregularly shaped sides and be asymmetrical. In other embodiments, a non-pressurized housing may substantially enclose other devices or payloads besides a node, such as weights or transponders, and be coupled to a plurality of protrusions.

Abstract: A submersible designed so that a cabin for boarding an operator has a size just enough to accommodate the operator and even such a light weight of the submersible can cause the submersible to submerge. Furthermore, when an operator having a weight smaller than a design maximum operator's weight of the submersible is on board, and therefore the total weight of the submersible is reduced and the buoyancy thereof is increased, the buoyancy of the submersible is adjusted by pouring water having a weight corresponding to a difference between the design maximum operator's weight and the actual weight of the operator into an expansion container, disposed in the cabin, capable of expanding by containing water. In this manner, the net weight of the submersible is prevented from increasing.

Abstract: A steerable seismic energy source includes at least one float. The floatation device includes a device for changing buoyancy thereof. A frame is coupled to the at least one float. At least one seismic energy source is suspended from the frame. At least one steering device is coupled to the floatation device or the frame. The at least one steering device includes at least one control surface and a control surface actuator coupled to the control surface. The actuator is configured to rotate the control surface to generate hydrodynamic lift at least in a vertical direction.

Abstract: Systems and methods for maneuvering an underwater vehicle by generating vehicle maneuvering forces from a propulsor of the vehicle are provided. A post-swirl propulsor is configured such that pitch angles of downstream stator blades can be individually varied. The variation in pitch results in the generation of multiple forces and moments for vehicle control.

Abstract: A buoyancy engine is provided for use in a saltwater environment. The engine includes a gas filled housing and a buoyancy chamber in the housing. An elastomeric membrane is positioned between the buoyancy chamber interior and the housing interior. A semi-permeable membrane is provided between the buoyancy chamber interior and the saltwater environment. Two electrodes can be positioned with both electrodes in the buoyancy chamber or with one electrode being positioned in the buoyancy chamber and the other being positioned in the saltwater environment. A controller is joined to at least one of the electrodes for controlling an electrical potential between the two electrodes. A power source provides power to the controller.

Abstract: An installation vehicle for a nacelle of a tidal power plant having a turbine-generator unit includes at least two floating devices with a plurality of ballast tanks, the buoyancy of which is settable, a drive device acting in different directions, and a controllable fastening device for holding the nacelle. The fastening device is connected at least indirectly to a support element, which produces a connection between the floating devices. The connection between the floating devices and the support element is embodied by a detachable coupling unit or the support element includes a device for size adaptation.

Abstract: Systems and methods for compensating for compressibility and thermal expansion coefficient mismatch in buoyancy controlled or buoyancy-driven underwater vehicles are disclosed herein. An underwater vehicle configured in accordance with one embodiment of the disclosure, for example, can include a hull and a compartment carried by the hull and at least partially flooded with a first liquid having similar properties as a surrounding liquid into which the hull is configured to be deployed. The first liquid has a first compressibility and thermal expansion coefficient. The underwater vehicle can further include a compressibility and thermal expansion coefficient compensation system comprising a container filled or at least partially filled with a compressible liquid comprising silicone in the compartment. The compressible liquid has a second compressibility higher than the first compressibility and second thermal expansion coefficient higher than the first thermal expansion coefficient.

Abstract: A floating, offshore drilling and/or production platform such as a tension leg platform, semi-submersible, spar or the like is equipped with a ballast tank system that comprises the traditional tank and a shaft that runs typically vertically from top-of-hull level to the top of the tank. This shaft is large enough to allow the ballast pipe, sounding lines, instrumentation piping, etc. to be installed within it. In certain embodiments, the shaft itself functions as a vent line.

Abstract: A multiple stage buoyancy changing system, or variable buoyancy device, for an underwater vehicle. The multiple stage buoyancy changing system comprises: a pressure hull containing a flexibly-sized internal fluid reservoir; a flexibly-sized external fluid reservoir attached to the pressure hull and connected to the internal reservoir; a system of devices and channels configured to move fluid between the internal fluid reservoir and the external fluid reservoir to change a displaced volume of the vehicle. Each stage of the variable buoyancy device can be optimized for maximum energy efficiency while changing the vehicle's displaced volume within an ambient pressure range. A control system for the variable buoyancy device engages different stages depending on ambient external pressure such that maximum energy efficiency is achieved over a large range of pressures/depths.

Abstract: An autonomous underwater vehicle (AUV) for recording seismic signals during a marine seismic survey. The AUV includes a body having a flush shape; an intake water element located on the body and configured to take in water; at least one propulsion nozzle located on the body and configured to eject the water from the intake water element for actuating the AUV; at least one guidance nozzle located on the body and configured to eject water to change a traveling direction of the AUV; and a seismic payload located on the body of the AUV and configured to record seismic signals.

Abstract: A dual pumping system for use on a movable flood control barrier structure to allow the structure to be swung into the opening of a waterway and sunk to prevent flooding during storms and then floated and swung out of the waterway after the storm is disclosed. A buoyant generally rectangular barge may be employed as the movable flood control barrier. A centrifugal pumping system pumps water into compartments within the barrier structure so it sinks to the bottom of the waterway while the same pumping system pumps water back to the waterway to float the structure. A hydraulic pumping system operates hydraulic winches to move the structure into and out of the channel using cables. The two pumping systems are capable of operating both the water pumping system and hydraulic winch system simultaneously or independently with a single engine.

Abstract: Systems and methods for compensating for compressibility and thermal expansion coefficient mismatch in buoyancy controlled or buoyancy-driven underwater vehicles are disclosed herein. An underwater vehicle configured in accordance with one embodiment of the disclosure, for example, can include a hull and a compartment carried by the hull and at least partially flooded with a first liquid having similar properties as a surrounding liquid into which the hull is configured to be deployed. The first liquid has a first compressibility and thermal expansion coefficient. The underwater vehicle can further include a compressibility and thermal expansion coefficient compensation system comprising a container filled or at least partially filled with a compressible liquid comprising silicone in the compartment. The compressible liquid has a second compressibility higher than the first compressibility and second thermal expansion coefficient higher than the first thermal expansion coefficient.

Abstract: Multi-stage buoyancy changing system for an autonomous underwater vehicle comprises: an internal reservoir configured to hold a fluid; an external bladder connected to the internal reservoir and configured to exchange fluid with the internal reservoir via one or more channels; a first device configured to move fluid through a channel from the internal reservoir to the external bladder at an optimized efficiency for an ambient pressure of a first segment of a dive profile to increase apparent displacement and buoyancy of the vehicle; and a second device configured to move fluid through a channel from the internal reservoir to the external bladder at an optimized efficiency for an ambient pressure of a second segment of the dive profile to increase an apparent displacement and a buoyancy of the vehicle. The first segment of the dive profile includes a different ambient pressure range than the second segment of the dive profile.

Abstract: Superfluous sealing, buoyancy and immersion controlling system for floating appliances having a primary, secondary and tertiary buoyancy systems, a buoyancy system of devices and operation and maintenance plants, a set of submersible pumps, a console for controlling and automating the immersion operations and a set of programmable valves. This superfluous system allows any appliance or platform to be able of easily being towed to its final location at sea, ocean, lake . . . regardless of the size, shape or weight thereof, and weather conditions. Similarly, this system enables the immersion at a controlled rate once the platform is in its final location.

Abstract: An autonomous system for blowing ballast for eliminating negative buoyancy of a submarine and a method of blowing the same. The autonomous system includes air supply balloons arranged in an area of the submarine protected from mechanical damage; trunk pipelines connected to the balloons for supplying gas to FDT of the submarine; shutoff devices for regulating the supply of gas via the trunk pipelines. According to the method realized using the disclosed system, compressed gas is supplied from the compressed air balloon, over the trunk pipelines, and into the FDT of the submarine. The invention provides bringing the negative buoyancy of the submarine to zero to stop the gravitational dive.

Abstract: An apparatus includes a housing and a ballast disposed within the housing. The ballast is adapted to receive, store and expel a fluid. A bladder is operatively coupled to the ballast wherein an increase in the volume of the bladder causes a decrease in the free volume of the ballast available for the storage of the fluid therewithin and a decrease in the volume of the bladder causes an increase in the free volume of the ballast available for the storage of the fluid therewithin. A heat exchanger has a heat exchange duct thermally coupled to the bladder and is adapted to receive a fluid from outside the housing. The bladder is configured to receive a clathrate.

Abstract: A buoyant submersible structure floating above the sea floor includes a support portion to support a load, and a gas-filled tank. The tank has an opening, and a connected tube. The tube is partially filled with seawater defining a water-gas interface at a first level. In operation, the structure is fully submerged below the water surface to a first depth. The second chamber is partially filled with seawater defining a water-gas interface at a first position inside the second chamber. Then, the buoyancy structure is moved to a second, greater depth. Water enters the second chamber to raise the water-gas interface to a second, higher level and without entering the first chamber. Subsequently, the buoyancy of the structure is adjusted to tension the cable, a support structure to support a load is attached to the structure, and then the buoyancy of the structure is readjusted.

Abstract: High velocity subsurface craft, apparatus or method positively affecting propulsion and limiting drag by the use of a rotating body with selected Surface Treatment. The Active Hull Platform provides Apparent Flows that allow for shorter more dispersed blade arrays and boundary layer management that impacts vorticity on skin surfaces by controlling the angular momentum of the vortices formed. By converting drag forces into thrust, vortices need not be avoided and an even non pulsating distributed thrust is the result.

Abstract: A water navigable vessel or glider can transport cargo across oceans and other bodies of water without the use of fossil or nuclear fuels. The vessel includes a housing, a cargo or payload area within the housing, one or more control fins attached to the housing, a ballast within the housing, an expandable and contractible container configured to receive a clathrate and maintain a minimum amount of pressure on the clathrate within the housing in proximity to the ballast, and an intake valve coupled to the ballast. The clathrate changes state, thereby changing the buoyancy of the glider, and causing the glider to move through the body of water.

Abstract: Technologies such as stealth buoys and underwater gliders need to modify their own buoyancy in order to operate. Strategies such as pumping fluid are typically used to change the device's net volume. This in turn requires a mechanically sophisticated apparatus, increasing the cost of the vehicle while diminishing its reliability. The concept of a buoyancy engine that exploits the enormous volume and pressure changes accompanying the reversible electrochemical interconversion of water to hydrogen and oxygen gases is applied to stealth buoys and underwater gliders.

Abstract: A water navigable vessel or glider can transport cargo across oceans and other bodies of water without the use of fossil or nuclear fuels. The vessel includes a housing, a cargo or payload area within the housing, one or more control fins attached to the housing, a ballast within the housing, an expandable and contractible container configured to receive a clathrate and maintain a minimum amount of pressure on the clathrate within the housing in proximity to the ballast, and an intake valve coupled to the ballast. The clathrate changes state, thereby changing the buoyancy of the glider, and causing the glider to move through the body of water.

Abstract: Disclosed is a buoyancy device for tensioning an elongate vertical (or quasi vertical) subsea structure at a point below the sea surface, anchored at its bottom. The device comprises as its main buoyancy elements a plurality of hollow elongate objects, and further comprises at least one auxiliary buoyancy element comprising a solid buoyant material. Ideally, the solid buoyant material provides enough uplift to maintain the device afloat should the main buoyancy elements be flooded. A riser apparatus comprising such a buoyancy device is also described.

Abstract: A water craft (10) includes a hull (12) defining two cavities (18). An inflatable chamber (22) is arranged in each cavity (18), for displacing water from hull (12), in use, to increase the buoyancy of the craft (10). As the chamber (22) is inflated, it expands to reduce the free space available for water in the cavity (18), so as to directly expel water from the cavity (18). The chamber (22) can be deflated, in order to flood the cavity and thereby sink the craft (10). The craft (10) is intended to be operated in a normal buoyant mode and in a submarine mode, and includes propeller means (34). The craft may be in the form of a catamaran-type vessel, a jet-ski, or a submersible tank.

Abstract: An apparatus includes a housing and a ballast disposed within the housing. The ballast is adapted to receive, store and expel a fluid. A bladder is operatively coupled to the ballast wherein an increase in the volume of the bladder causes a decrease in the free volume of the ballast available for the storage of the fluid therewithin and a decrease in the volume of the bladder causes an increase in the free volume of the ballast available for the storage of the fluid therewithin. A heat exchanger has a heat exchange duct thermally coupled to the bladder and is adapted to receive a fluid from outside the housing. The bladder is configured to receive a clathrate.

Abstract: A buoyancy system includes a chamber having a volume associated therewith, and bladders within the volume of the chamber. Each bladder contains a clathrate mixture in a liquid state. The chamber includes an opening to allow surrounding water to circulate within the volume and contact the bladders. As the chamber is submerged in the surrounding water, the bladders expand based on the clathrate mixture changing from the liquid state to a solid state. This changes buoyancy by allowing less water to circulate within the volume of the chamber.

Abstract: The object of the invention is a method for installing and servicing an apparatus module (1) recovering the kinetic energy of water; and the apparatus module (1) itself. The apparatus module (1) with wave energy recovering units (3) is descended into the sea bottom (12) and is kept steady at the sea bottom (12) by the help of its own mass and the mass of the water filled into the compartments (2a and 2c) in the body (2) of the apparatus module (1). Correspondingly the apparatus module (1) is lifted into the surface of the water and made floating by the help of air that is blown to the compartments (2a) and (2c) in order to replace the water.