Fluid-Based Buoyancy Compensation

• US 20160229502A1
• Filed: 04/22/2016
• Published: 08/11/2016
• Est. Priority Date: 03/02/2012
• Status: Active Grant

• Current Assignee: Sea-Bird Electronics, Inc. (Danaher Corporation)
• Original Assignee: Sea-Bird Electronics, Inc. (Danaher Corporation)
• Inventors: Edwards, Bradley C.
• Granted Patent: US 10,144,493 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B63B 17/00 Vessels parts, details, or accessories, not otherwise provided for vehicle fittings for preventing or indicating unauthorised use or theft of vehicles in general B60R25/00; propeller guards, line cutters or other means for protecting propellers or rudders B63H5/165; protection of power legs of outboard propulsion units B63H20/36; locking devices for boats, surfboards or parts or accessories thereof E05B73/007
• CPC Class Codes: B63C 7/10 using inflatable floats external to vessels or objects
• CPC Class Codes: B63G 8/14 Control of attitude or depth of torpedoes F42B19/00
• CPC Class Codes: B63G 8/24 Automatic depth adjustment; Safety equipment for increasing buoyancy, e.g. detachable ballast, floating bodies

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.

Claims

1. A method comprising:

receiving a target depth for a submersible vessel;

determining, using a sensor module, a current depth of the submersible vessel;

adjusting, based on the current depth and the target depth, the buoyancy of the submersible vessel using a compressible fluid within an expandable container.

2. The method of claim 1, wherein the compressible fluid includes an electrically activated porous hydrophobic powder and wherein adjusting the buoyancy comprises applying an electrostatic field to the compressible fluid.

3. The method of claim 2, wherein the compressible fluid has a compressibility profile and the method further comprises determining a voltage of the electrostatic field resulting in a desired compressibility of the fluid.

4. The method of claim 1, wherein adjusting the buoyancy of the submersible vessel includes using a pump to adjust an amount of the compressible fluid within the expandable container.

5. The method of claim 1, further comprising:

recording measurements of a liquid surrounding the submersible vessel; and

communicating, using a communications module, the measurements of the liquid to a remote base station.

6. The method of claim 5, wherein the measurements of the surrounding liquid includes measurements of salinity, temperature, or pressure.

7. The method of claim 5, wherein adjusting the buoyancy of the submersible vessel is also based on temperature or salinity of the liquid surrounding the submersible vessel.

8. The method of claim 1, wherein adjusting the buoyancy of the submersible vessel is also based on a current rate of ascent or descent.

9. A submersible vessel comprising:

a communications module to receive a target depth for the submersible vessel;

a sensor module to determine a current depth of the submersible vessel;

a buoyancy subsystem to adjust, based on the current depth and the target depth, the buoyancy of the submersible vessel using a compressible fluid within an expandable container.

10. The submersible vessel of claim 9, wherein the compressible fluid includes an electrically activated porous hydrophobic powder and wherein the buoyancy subsystem includes electrostatic plates to adjust the buoyancy by applying an electrostatic field to the compressible fluid.

11. The submersible vessel of claim 10, wherein the compressible fluid has a compressibility profile and the buoyancy subsystem determines a voltage of the electrostatic field resulting in a desired compressibility of the fluid.

12. A buoyancy compensation system comprising:

a compressible fluid that includes a mixture of a hydrophobic powder and a liquid; and

a flexible container to hold the compressible fluid.

13. The buoyancy compensation system of claim 12, wherein the flexible container includes a rubber bladder.

14. The buoyancy compensation system of claim 12, wherein the hydrophobic powder is an electrically activated porous hydrophobic powder and the buoyancy compensation system applies an electrostatic field to the compressible fluid to adjust compressibility resulting in a change of buoyancy of the vessel.

15. The buoyancy compensation system of claim 14, wherein the buoyancy compensation system includes electrostatic plates to apply the electrostatic field to the compressible fluid.

16. The buoyancy compensation system of claim 12, wherein the hydrophobic powder includes silica.

17. The buoyancy compensation system of claim 12, wherein the liquid includes an electrolyte.

18. The buoyancy compensation system of claim 12, further comprising a pump operatively coupled to the flexible container and configured to adjust an amount of the compressible fluid within the flexible container.

19. The buoyancy compensation system of claim 12, wherein the compressible fluid has a compressibility of about twenty-five times the compressibility of water.

20. The buoyancy compensation system of claim 12, further comprising a hydraulic controller to move oil into a second container to adjust the buoyancy of the vessel.