Abstract: A method includes obtaining sensor data indicating a tension experienced by a tether while a payload coupling apparatus connected to the tether is lowered from an aerial vehicle using the tether. The method also includes determining, based on the sensor data, a ground contact time at which the payload coupling apparatus or a payload coupled thereto made initial contact with a ground surface. The method additionally includes determining a length of the tether released from the aerial vehicle at the ground contact time. The method further includes determining a tether-based altitude of the aerial vehicle based on the length of the tether released from the aerial vehicle at the ground contact time. The method yet further includes causing the aerial vehicle to perform an operation based on the tether-based altitude.

Abstract: An underwater watercraft including a passenger compartment and an ingress/egress port in which the watercraft has buoyancy and center of gravity adjusted to maintain a generally level or other desired attitude when submerged, and an optionally angled attitude at a water surface for ingress/egress. The attitude is also adjustable via the placement of ballast and optionally including a movable ballast that adjusts the location of the center of gravity as desired. The ingress-egress port optionally includes an entry elevated from a main passenger compartment and including a riser and optionally removable or concealable handrails. The ingress-egress port has an angled orientation in a submerged mode, and an optional orientation generally parallel to the water surface or angled but above the surface in a surface mode.

Abstract: A heave survey platform includes: a body, two fixed wings and two variable wing mechanisms. The two fixed wings are symmetrically disposed on two sides of a middle part of the body, and an axis of the body is located in a plane defined by extension directions of the two fixed wings. Each variable wing mechanism includes a variable wing, and the two variable wings of the two variable wing mechanisms are symmetrically disposed on two sides of a lower end of the body, and each variable wing is configured to swing between a first position coplanar with the plane and a second position forming an angle with the plane to generate a lift force on the body at the second position, thereby to make the body move in a radial direction or change attitude.

Abstract: A driving method is implemented to a lifting device of an underwater survey system, and the lifting device includes a phase-change heat exchange module, an oil bag module, a pressurized energy storage module, and a drive energy storage module. The driving method includes: controlling the pressurized energy storage module to extract hydraulic oil in the oil bag module to descend the lifting device; during a transformation of a phase-change material, the pressurized energy storage module transmitting hydraulic oil to the phase-change heat exchange module; transmitting the hydraulic oil inside the oil bag module to the pressurized energy storage module to descend the lifting device; controlling the drive energy storage module to transmit hydraulic oil to the oil bag module for rising the lifting device; and during a transformation of the phase-change material, transmitting the hydraulic oil in the phase-change heat exchange module to the drive energy storage module.

Abstract: An underwater watercraft including a passenger compartment and an ingress/egress port in which the watercraft has buoyancy and center of gravity adjusted to maintain a generally level or other desired attitude when submerged, and an optionally angled attitude at a water surface for ingress/egress. The attitude is also adjustable via the placement of ballast and optionally including a movable ballast that adjusts the location of the center of gravity as desired. The ingress-egress port optionally includes an entry elevated from a main passenger compartment and including a riser and optionally removable or concealable handrails. The ingress-egress port has an angled orientation in a submerged mode, and an optional orientation generally parallel to the water surface or angled but above the surface in a surface mode.

Abstract: Disclosed is an ocean bottom electromagnetic acquisition station communication apparatus and method. The ocean bottom electromagnetic acquisition station communication apparatus includes: ocean bottom electromagnetic acquisition stations (1) for acquiring ocean bottom electromagnetic information; a control terminal (2) for sending control signals; and a relay timing module (3) connected to the ocean bottom electromagnetic acquisition stations (1) and the control terminal (2) and used for processing the ocean bottom electromagnetic acquisition stations (1) on the basis of the control signals before placement.

Abstract: An underwater body having a movable component which can be moved into a retracted position and, as a result, increases the volume of the underwater body. In addition, a method is disclosed for operating such an underwater body. An expansion means conducts a fluid into a hollow space. The hollow space is operatively connected to the movable component. When the fluid is conducted into the hollow space, the movable component is moved into the extended position relative to the shell of the underwater body. The fluid in the hollow space hardens. The hardened fluid in the hollow space holds the movable component in the extended position.

Abstract: An underwater watercraft including a passenger compartment and an ingress/egress port in which the watercraft has buoyancy and center of gravity adjusted to maintain a generally level or other desired attitude when submerged, and an optionally angled attitude at a water surface for ingress/egress. The attitude is also adjustable via the placement of ballast and optionally including a movable ballast that adjusts the location of the center of gravity as desired. The ingress-egress port optionally includes an entry elevated from a main passenger compartment and including a riser and optionally removable or concealable handrails. The ingress-egress port has an angled orientation in a submerged mode, and an optional orientation generally parallel to the water surface or angled but above the surface in a surface mode.

Abstract: An expansion chamber for use on a tubular includes a shell that is configured to be attached to the tubular by a bonding material, the shell having a port configured to receive the bonding material therethrough and into a cavity of the shell. The expansion chamber also includes a tube unit configured to be placed in the cavity of the shell, the tube unit having a tube with a port that is in fluid communication with the port of the shell.

Abstract: It is an object of the present invention to provide a means of constructing an Autonomous fully-Submersible Offshore Marine Platform (ASOMP) of considerable warfighting or commercial capability which is mobile and can autonomously transport to a hazardous operating area in a low-observable reduced vulnerability manner, fully submerge to avoid the military or environmental threat hazard, hibernate until needed, perform fully submerged mobility and mission operations, surface and provide Barge and SWATH surface ship mobility and mission operations, resubmerge if the hazardous threat appears and relocate to a new operating area. Another object of the present invention is to provide a fully autonomous and submersible low-cost “lily-pad” that surfaces when called and provides a main deck platform at appropriate freeboard and seakeeping motions to function as a refueling landing zone and pier to extend the range of aircraft and marine vehicles operating in a high-threat environment.

Abstract: A system and method for protecting a lightweight pressure vessel capable of airborne and underwater use. The system includes an enclosure and a gas container that is capable of holding pressurized or liquefied gas in sufficient quantity to increase internal pressure of the pressure vessel, so that the internal pressure of the pressure vessel equals an external pressure of the pressure vessel. The system also includes a pressure relief device coupled to the enclosure. The pressure relief device is configured to release the pressurized or liquefied gas from the pressure vessel when the internal pressure exceeds the external pressure by a predetermined amount. The system also includes a gas supply mechanism coupled to the gas container, the gas supply mechanism being configured to allow gas from the gas container into order to increase the internal pressure of the pressure vessel until the internal pressure equals the external pressure.

Abstract: An underwater vehicle is configured to transfer a payload between a first location and a second location at a subsea structure. The underwater vehicle includes a payload support configured to support the payload and a buoyancy control system. The buoyancy control system includes at least one of an exchange weight system configured to receive one or more exchange weights when delivering the payload, a floatation system having one or more floatation devices coupled to the payload, or a combination thereof.

Abstract: A keel canting mechanism for a sailing vessel having a hull, a keel and a mast is disclosed. The mechanism comprises a worm gear co-axial with the longitudinal axis of the vessel about which the keel rotates during a canting movement. There is a double enveloping worm in mesh with the worm gear and means for driving the worm. The worm gear is fast with the keel and, when rotated by the worm, displaces the keel through a canting movement. The gear has a plurality of holes in it into which pins can be inserted to lock the gear, and hence the keel, in the position to which it has been moved by the worm.

Abstract: A method of obtaining data with a sensor of an autonomous underwater vehicle (AUV), the AUV comprising a bladder which contains a gas and is exposed to ambient water pressure. A downward thrust force is generated which causes the AUV to descend through a body of water, wherein the bladder contracts as the AUV descends due to an associated increase in the ambient water pressure, the contraction of the bladder causing the gas to compress and the AUV to become negatively buoyant. Next the AUV lands on a bed of the body of water. After the AUV has landed on the bed, the sensor is operated to obtain data with the AUV stationary and negatively buoyant and a weight of the AUV supported by the bed.

Abstract: Antenna systems for receiving transmitted signals comprising at least a first tuned antenna disposed in a known relationship spatially with a second antenna, with the first tuned antenna electrically connected to the second antenna, are disclosed. The antenna system may be configured to allow the antennas to reliably discriminate between left-hand and right-hand circular signals.

Abstract: Antenna systems for receiving transmitted signals comprising at least a first tuned antenna disposed in a known relationship spatially with a second antenna, with the first tuned antenna electrically connected to the second antenna, are disclosed. The antenna system may be configured to allow the antennas to reliably discriminate between left-hand and right-hand polarized circular signals.

Abstract: The present invention provides a self-draining oil buoyancy regulating device for underwater robots, wherein the accumulator, lower hatch cover, hatch trunk, upper hatch cover and bladder are connected; the water-proof connector is fixed on the upper hatch cover; the depth-pressure sensor is settled on the lower hatch cover; the upper valve block, hydraulic-operated check valve and lower valve block are connected; the lower valve block is fixed on the lower hatch cover; the pump outlet pressure sensor and the accumulator pressure sensor are on the lower valve block; the directional valve and the upper valve block are connected; the hydraulic pump motor assembly and the relief valve are both connected with the lower valve block; the depth-pressure sensor, pump outlet pressure sensor and accumulator pressure sensor are all connected with the control panel; the control panel is connected with the external power supply and the host computer.

Abstract: A combustion buoyancy control system for a submersible object is provided. The buoyancy control system includes a piston cylinder and a piston defining a combustion chamber. An oxidizer inlet introduces oxidizer into the combustion chamber. A fuel injector and igniter device injects fuel into the combustion chamber so that it mixes with the oxidizer in the combustion chamber and then ignites the mixture of oxidizer and fuel in the combustion chamber to produce combustion. Combustion within the combustion chamber displaces the piston member in a first direction causing an increase in the volume of the combustion chamber which increases the buoyancy of the submersible object. Displacement of the piston member in a second opposite direction causes a decrease in the volume of the combustion chamber which in turn decreases the buoyancy of the submersible object.

Abstract: Systems and methods for buoyancy compensation are provided. Both active and passive buoyancy compensation can be provided using a compressible mixture made of a liquid along with a hydrophopic material such as a powder, electrospun fiber, or foam. The compressible fluid compresses as pressure is applied or expands as pressure is released thereby substantially maintaining an overall neutral buoyancy for a vessel. This allows the vessel to ascend and descend to water depths with minimal active buoyancy change. As a result, the energy usage and the reliance on higher pressure air and oils can be minimized.

Abstract: A traffic monitoring system and method for mapping traffic speed and density while preserving privacy. The system can include fixed stations that make up a network and mobile probes that are associated with vehicles. The system and method do not gather, store, or transmit any unique or identifying information, and thereby preserves the privacy of members of traffic. The system and method provide real-time traffic density and speed mapping. The system and method can further be integrated with a complementary flood monitoring system and method.

Abstract: A valve monitoring system includes a latching valve, a travel sensor, and a processor. The latching valve has a snap spring, a valve piston, and an inlet port. The travel sensor is for measuring travel of the valve piston between an activation pressure and a zero pressure. The processor is connected to the travel sensor for calculating a rate of travel of the valve piston and determining a latched state of the valve. In some example embodiments, the activation pressure is greater than a normal operating pressure. In some example embodiments, determining a latched state of the valve includes calculating a derivative of the rate of travel.

Abstract: Systems and methods for buoyancy compensation are provided. Both active and passive buoyancy compensation can be provided using a compressible mixture made of a liquid along with a hydrophopic material such as a powder, electrospun fiber, or foam. The compressible fluid compresses as pressure is applied or expands as pressure is released thereby substantially maintaining an overall neutral buoyancy for a vessel. This allows the vessel to ascend and descend to water depths with minimal active buoyancy change. As a result, the energy usage and the reliance on higher pressure air and oils can be minimized.

Abstract: A manned submarine for underwater viewing and experience. A viewing window through which an outside view can be seen is disposed above the body of the submarine. The viewing window has an internal space and is open in the lower portion thereof. The propulsion systems provides a propelling force to the body. The ascending and descending system allows the manned submarine to ascend on the water or to descend under the water. The control box disposed at the forecastle of the body controls the operations of the propulsion systems, and the ascending and descending system. The viewing window is disposed above the crew room and is configured to allow water to enter the crew room except the internal space of the viewing window to allow the passengers to breathe underwater and provide a high level of leisure experience in addition to the visual viewing experience.

Abstract: In various embodiments a variable buoyancy profiling float is disclosed. The variable buoyancy profiling float may comprise a spherical glass housing comprising a first hemisphere and a second hemisphere. The first and second hemispheres may be coupled by a partial vacuum within the spherical glass housing. A buoyancy system may be located at least partially within the spherical glass housing. The buoyancy system may be configured to provide variable buoyancy control to the variable buoyancy profiling float. A sensor bundle may be mounted to the spherical glass housing and may be configured to measure at least one environmental parameter.

Abstract: An underwater load-carrier is disclosed that includes an underwater-balloon detachably attached to a container that is loaded with ballast. The underwater load-carrier is lowered into the water of an ocean and allowed to descend to the ocean bottom and there connected a mining-vehicle. The mining-vehicle loads mined nodules into the container while the container ejects ballast to maintain the container at a specified altitude above the ocean bottom. When nodule loading is complete, nodules and/or ballast is ejected to allow underwater load-carrier to rise to the ocean surface where mined nodules is unloaded from the container.

Abstract: A system for attitude control of an underwater vehicle 20 of the present invention includes an underwater vehicle 20 with a thruster 65, an assist device 10 that is coupled to the underwater vehicle 20 with a cable 1 and has cable handling equipment 2 and a thruster 58, a cable attachment-to-attachment distance detection unit 50 that detects distance between a cable attachment of the underwater vehicle 20 and a cable dispenser of the assist device 10, and a control unit 32 that previously stores the relationship between the attachment-to-attachment distance and cable length including a predetermined amount of slack and determines the amount of cable to be wound up or let out based on the cable length associated with the detected attachment-to-attachment distance.

Abstract: A self-propelled microbial fuel cell apparatus includes a microbial fuel cell with a cathode electrode and an anode electrode wherein the anode electrode is enclosed within an enclosure that has an opening in it. The microbial fuel cell is positioned within a self-propelled delivery vehicle so that the electrodes of the fuel cell are exposed to interface with a microbial environment.

Abstract: An autonomous underwater vehicle (AUV) for recording seismic signals during a marine seismic survey. The AUV includes a body having a base and sides; a propulsion system for guiding the AUV to a final target on the ocean bottom; a pump-jet connected to an inlet and plural base outlets, wherein the plural base outlets are distributed on the base; a processor connected to the pump-jet and configured to activate the pump-jet when the base in on the ocean bottom; and a seismic sensor configured to record seismic signals. The pump-jet has a first low speed so that water jets expelled at the plural base outlets fluidize the ocean bottom underneath the base and buries the AUV.

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: A method for operating a submersible vehicle includes, responsive to detection of a vortex ring undesirably affecting the vehicle and/or at least one vehicle condition indicating the presence of a vortex ring undesirably affecting the vehicle, initiating at least one control action to mitigate the effect of the vortex ring on the vehicle.

Abstract: A method for detecting anomalies on a submarine object, in particular in the submarine region on a hull of a moored warcraft, which method carries out very reliable sensing of the submarine object by way of an unmanned small submarine vehicle that is equipped with simple sensor equipment, such as an acoustic sensor for measuring distances and a barometric cell for determining depth, and which method obtains a profile of the submarine object by navigating the small submarine vehicle with a constant transversal distance to the submarine object, in which profile an anomaly present on the submarine object becomes is apparent from the profile line.

Abstract: An activation module to be used in a seismic equipment recovery device. The activation module includes a processor; a pressure transducer configured to measure a pressure of the ambient and provide the measured pressure to the processor; a memory connected to the processor and configured to store information related to a pressure or depth threshold; and a communication unit connected to the memory and configured to exchange information with an external device. The processor is configured to send a deployment instruction to an inflation mechanism to inflate a flotation bag based on the measured pressure and the stored information.

Abstract: A method of using a buoyancy fluid presenting density that is less than that of sea water, and that is confined in a rigid or flexible leaktight casing, so as to constitute an immersed buoyancy element, wherein the buoyancy fluid is a compound that is naturally in a gaseous state at ambient atmospheric temperature and pressure, and in a liquid state at the underwater depth to which the buoyancy element is immersed. A method is also disclosed for placing a buoyancy element in place between the surface and the bed of the sea, wherein fluid is stored in a tank on a surface ship as a liquid in the cooled or compressed liquid state, and is injected in the liquid state into a pipe from the surface where it is stored to an immersed casing at an underwater depth at which the underwater pressure is not greater than the vapor pressure of the gas corresponding to the compound at the temperature at the depth.

Abstract: A telescopic submarine includes: a front submarine unit (1), a rear submarine unit (2), and a lift tower (3). A ring-shaped piston (14) connected with the rear submarine unit (2) is in a hydrocylinder (7) connected with the front submarine unit (1). When the piston (14) is moved forward, a volume of the telescopic submarine is decreased, a specific gravity of the telescopic submarine is increased, and therefore the telescopic submarine dives into the water gradually. The telescopic submarine is able to surface via operating the horizontal rudder (20) to raise the telescopic submarine to a surface of the water, and then pumping the hydraulic oil (32) into the hydrocylinder (7) via the hydraulic pump (11) to drive the piston (14) to move backward. Therefore the volume of the telescopic submarine is increased, the specific gravity of the telescopic submarine is decreased, and the telescopic submarine surfaces.

Abstract: A self-scuttling device can include a pressure hull that can define an internal void having an internal pressure PVOID. The device can be disposed in an underwater environment having a pressure PAMBIENT that is greater than PVOID. The pressure hull can be formed with a fill port, which can be selectively opened to flood the void. A reactive agent can be disposed within the void. The reactive agent can be chosen to mix with seawater and establish a solution that corrodes the pressure hull when the reactive agent is exposed to seawater by flooding the void. The reactive agent can be disposed within a watertight container, which maintains watertight integrity at PVOID, but loses watertight integrity at the greater PAMBIENT. When this occurs, the reactive agent becomes exposed to seawater to establish the solution within the void that corrodes the pressure hull.

Abstract: A method for operating a submersible vehicle includes, responsive to detection of a vortex ring undesirably affecting the vehicle and/or at least one vehicle condition indicating the presence of a vortex ring undesirably affecting the vehicle, initiating at least one control action to mitigate the effect of the vortex ring on the vehicle.

Abstract: A electronic pet contains a diving device which includes a sealed main body with at least one flexible portion disposed on at least one part of the main body wherein the sealed main body is sealed from water external to the sealed main body by the at least one flexible portion together with the main body, and an actuator, directly connected to the flexible portion through a transmission shaft, wherein the actuator is adapted for controlling the air density of the diving device by pulling or pushing the flexible portion inwards or outwards through the transmission shaft respectively. The electronic pet also includes a driving device, a sensing device used to sense light, sound and contact/non-contact stimulations from an external environment, a signal transceiver device used to transceive signals to and from devices other than the electronic pet, and a processor.

Abstract: A craft includes a rigid hull (1) that consists of a V-shaped bottom (5) and a bridge (4) on which a load can rest. The hull includes plating consisting of compartmentalized pneumatic floats (2), the rear compartments (32) of which are combined with an inflation and deflation system so as to vary the buoyancy of the craft. The craft also includes a submergible hull (1), the central cavity (9) of which is formed between the bottom (5) and the bridge (4) and is open at the rear so as to be automatically filled or emptied, the central cavity (9) containing at least one bag (10) that is combined with an inflation and deflation system enabling the buoyancy to be varied and consequently the level of immersion of the stern (7) to be changed as needed.

Abstract: A electronic pet contains a diving device which includes a sealed main body with at least one flexible portion disposed on at least one part of the main body wherein the sealed main body is sealed from water external to the sealed main body by the at least one flexible portion together with the main body, and an actuator, directly connected to the flexible portion through a transmission shaft, wherein the actuator is adapted for controlling the air density of the diving device by pulling or pushing the flexible portion inwards or outwards through the transmission shaft respectively. The electronic pet also includes a driving device, a sensing device used to sense light, sound and contact/non-contact stimulations from an external environment, a signal transceiver device used to transceive signals to and from devices other than the electronic pet, and a processor.

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: Disclosed are an underwater moving apparatus and a moving method thereof. The underwater moving apparatus of an exemplary embodiment of the present invention includes a body; a propelling device installed on a rear side of the body; a thruster unit including an up and down directional thruster and a left and right directional thruster installed at the body; and a plurality of leg units positioned at both side portions of the body and including a multi-joint module.

Abstract: A chamber device that collects, contains, and transfers undersea leaking hydrocarbon fluids from various possible leak sources, comprises a remote controller cooperating with valves and sensors to automatically modulate the transfer flow rates of one or more fluids from the device to cooperating industry equipment. The device remote controller further comprises procedural data with simulation derived process control data, and cooperates with other sensors, valves, and external data inputs to enable updated interactive procedural data, with updated process control data to reduce the probability of error while enabling automated control functions during deployment, descent, and operation. Sea surface methods of loading ballast and low density fluids combine to deliver the very large negative buoyant force to the leak site where a method to release the ballast enables device recovery.

Abstract: Systems and methods for buoyancy compensation are provided. Both active and passive buoyancy compensation can be provided using a compressible mixture made of a liquid along with a hydrophopic material such as a powder, electrospun fiber, or foam. The compressible fluid compresses as pressure is applied or expands as pressure is released thereby substantially maintaining an overall neutral buoyancy for a vessel. This allows the vessel to ascend and descend to water depths with minimal active buoyancy change. As a result, the energy usage and the reliance on higher pressure air and oils can be minimized.

Abstract: An underwater load-carrier is disclosed that includes an underwater-balloon detachably attached to a container that is loaded with ballast. The underwater load-carrier is lowered into the water of an ocean and allowed to descend to the ocean bottom and there connected a mining-vehicle. The mining-vehicle loads mined nodules into the container while the container ejects ballast to maintain the container at a specified altitude above the ocean bottom. When nodule loading is complete, nodules and/or ballast is ejected to allow underwater load-carrier to rise to the ocean surface where mined nodules is unloaded from the container.

Abstract: An electronic pet and a system therewith are provided herein. The electronic pet includes a driving device, a sensing device used to sense light, sound and contact/non-contact stimulations from an external environment, a signal transceiver device used to transceive signals to and from devices other than the electronic pet, and a processor. The pet interaction system includes an electronic pet, a system sensing device used to sense a position of the electronic pet and a physiological status of a user, a dummy, a system signal transceiver device used to transceive signals to and from the electronic pet and the dummy, and a system processor.

Abstract: A submersible apparatus is configured to eject air and/or water in desired predetermined patterns to simulate particular types of ordnance to facilitate safe and effective splash testing of ship radar systems. The apparatus includes a frame, one or more adjustable buoyancy bodies, a source of fluid such as an air compressor or a water pump, and a plurality of nozzles through which the fluid is ejected to create the desired splash. Fluid can be supplied to the buoyancy bodies to adjust the level of the apparatus in the water as necessary to simulate a particular type of ordnance. Additionally, the nozzles can be individually adjustable to facilitate ordnance simulation. A control system is provided to enable remote and/or preprogrammed control of the apparatus. A wireless or hard wired link can be provided to allow a remote user to control the apparatus in real time.

Abstract: An unmanned submersible vehicle for use in a body of liquid having a top surface and in air overlying the top surface includes a hull, an integral antenna, and an antenna positioning system. The hull has first and second opposed ends. The hull includes a first hull portion adjacent the first end and a second hull portion adjacent the second end. The antenna is disposed within the first hull portion and/or is mounted on the first hull portion. The antenna positioning system is configured to reorient the hull from a transit position to a signal position.

Abstract: The present disclosure relates to a device for lifting and lowering a load in water, including a hoisting gear with a first hoisting rope and a storage drum with a second hoisting rope, which preferably are arranged on a floating unit. In accordance with the present disclosure, a hoisting gear frame is fastened to the first hoisting rope, whose buoyancy in water is variably adjustable. Furthermore, the present disclosure relates to a method for lifting and lowering a load in water by using such a device.

Abstract: A telescopic submarine includes: a front submarine unit (1), a rear submarine unit (2), and a lift tower (3). A ring-shaped piston (14) connected with the rear submarine unit (2) is in a hydrocylinder (7) connected with the front submarine unit (1). When the piston (14) is moved forward, a volume of the telescopic submarine is decreased, a specific gravity of the telescopic submarine is increased, and therefore the telescopic submarine dives into the water gradually. The telescopic submarine is able to surface via operating the horizontal rudder (20) to raise the telescopic submarine to a surface of the water, and then pumping the hydraulic oil (32) into the hydrocylinder (7) via the hydraulic pump (11) to drive the piston (14) to move backward. Therefore the volume of the telescopic submarine is increased, the specific gravity of the telescopic submarine is decreased, and the telescopic submarine surfaces.

Abstract: A buoyancy control system comprises a housing, first and second pistons, and a source of pressurized air. The pistons are coaxially aligned and are supported by the housing such that movement of the pistons changes a volume of a control chamber. In a shallow mode, fluid flows from the source of pressurized fluid to the first piston such that the pressurized fluid displaces the first piston to alter the volume of the control chamber and thus a buoyancy of the buoyancy control system. In a deep mode, fluid flows from the source of pressurized fluid to the first and second pistons such that the pressurized fluid displaces both of the first and second pistons to alter the volume of the control chamber and thus the buoyancy of the buoyancy control system.