A variable buoyancy device has an inner region and an outer cavity. The outer cavity extends at least partially around the inner region and is adapted to contain fluids, such as a liquid and a gas, the relative proportions of which can be varied to vary buoyancy. The inner region provides an advantageous location for equipment, while the outer cavity provides a significant volume for achieving a wide range of buoyancy adjustments.

A system for retrieval of objects submerged and lost in water is disclosed. The system comprises a gas release cartridge, an activation assembly arranged for activation of the gas release cartridge in response to at least one of: lapse of time, pressure, trigger-wire, indirect water contact, or remote acoustic command or any combination thereof, components of which are all contained in an inflatable bladder. A guide line, one end thereof attached to the bladder and the other end connectable to the object, is housed inside a non-watertight casing together with the inflatable bladder.

A system for retrieval of objects submerged and lost in water is disclosed. The system comprises a gas release cartridge, an activation assembly arranged for activation of the gas release cartridge in response to at least one of: lapse of time, pressure, trigger-wire, indirect water contact, or remote acoustic command or any combination thereof, components of which are all contained in an inflatable bladder. A guide line, one end thereof attached to the bladder and the other end connectable to the object, is housed inside a non-watertight casing together with the inflatable bladder.

A float apparatus for preventing the loss of a bow accidentally dropped in a body of water, the apparatus including a hydrostatic valve, a camshaft, a plunger, a gas cartridge and a bladder, all of which are operatively coupled to one another by a valve frame contained within a housing. When a bow having the float apparatus attached thereto is submerged, the hydrostatic valve automatically rotates the camshaft when the float apparatus reaches a desired depth. As the camshaft rotates, it presses against the plunger causing it to pierce the gas cartridge thereby releasing a gas. The gas is then directed through the valve frame into the bladder thereby inflating the bladder and causing the bow to float.

A float apparatus for preventing the loss of a bow accidentally dropped in a body of water, the apparatus including a hydrostatic valve, a camshaft, a plunger, a gas cartridge and a bladder, all of which are operatively coupled to one another by a valve frame contained within a housing. When a bow having the float apparatus attached thereto is submerged, the hydrostatic valve automatically rotates the camshaft when the float apparatus reaches a desired depth. As the camshaft rotates, it presses against the plunger causing it to pierce the gas cartridge thereby releasing a gas. The gas is then directed through the valve frame into the bladder thereby inflating the bladder and causing the bow to float.

A self-deployable apparatus for facilitating collecting data from multiple depths of water bodies. Further, the self deployable apparatus comprises a main body, substances, a sensor, a storage device, and a power source. Further, the substances in amounts are to be disposed in a second interior space of the main body for sinking the self-deployable apparatus to a depth of water body. Further, the amounts of the substances undergo a thermochemical reaction at a temperature for producing a gaseous substance. Further, a check valve of the main body expels a portion of the gaseous substance from the second interior space for rising the self-deployable apparatus to a surface of the water body. Further, the sensor generates sensor data based on detecting a parameter of a water sample. Further, the storage device stores the sensor data. Further, the power source powers the sensor and the storage device.

A self-deployable apparatus for facilitating collecting data from multiple depths of water bodies. Further, the self deployable apparatus comprises a main body, substances, a sensor, a storage device, and a power source. Further, the substances in amounts are to be disposed in a second interior space of the main body for sinking the self-deployable apparatus to a depth of water body. Further, the amounts of the substances undergo a thermochemical reaction at a temperature for producing a gaseous substance. Further, a check valve of the main body expels a portion of the gaseous substance from the second interior space for rising the self-deployable apparatus to a surface of the water body. Further, the sensor generates sensor data based on detecting a parameter of a water sample. Further, the storage device stores the sensor data. Further, the power source powers the sensor and the storage device.

A variable buoyancy device has an inner region and an outer cavity. The outer cavity extends at least partially around the inner region and is adapted to contain fluids, such as a liquid and a gas, the relative proportions of which can be varied to vary buoyancy. The inner region provides an advantageous location for equipment, while the outer cavity provides a significant volume for achieving a wide range of buoyancy adjustments.

A technique for varying buoyancy of an apparatus includes providing a substrate configured to produce gas on demand when exposed to a liquid, exposing the substrate to such liquid, and capturing the gas produced by the substrate to increase the buoyancy of the apparatus within a fluid. In some examples, the liquid and the fluid contain the same material, such that gas may be produced using fluid already in the environment.

A water-surface wave-absorbing structure comprises an equipment cabin and an airbag cabin vertically mounted below the equipment cabin; a solar cell module and an energy storage device in the equipment cabin are mounted on an upper surface of the equipment cabin, a signal transceiver is mounted on top portions of the solar cell module and the energy storage device, a central air distributing device is mounted in the equipment cabin, two ends of the central air distributing device are respectively connected to an air compressor and an air storage tank through vent pipelines, and a central controller is arranged in the central air distributing device and sends control instructions to the central air distributing device and the air compressor; and the airbag cabin comprises a plurality of airbag units, each airbag unit is provided with a plurality of mutually independent air chambers.