# US 9,517,821 B2 · Recovery systems and methods for unmanned underwater vehicles > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,517,821 B2 - Document ID: US9517821B2 - Status: Granted - Kind: B2 - Application number: 14/481,113 - Filed: 2014-09-09 - Published: 2016-03-10 - Granted: 2016-12-13 - Earliest claimed: 2014-09-09 - Assignees: The Boeing Company - Applicants: The Boeing Company - Inventors: Thomas S. Ford; Derek A. Ahern - Web page: https://patentgrep.com/patent/US9517821B2 ## CPC - B63G 8/14: Control of attitude or depth (of torpedoes F42B19/00) - B63G 8/24: Automatic depth adjustment; Safety equipment for increasing buoyancy, e.g. detachable ballast, floating bodies - B63G: OFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS (means of attack or defence in general, e.g. turrets F41H) ## Abstract Embodiments described herein provide a highly reliable UUV recovery systems and methods that utilize multiple independent release mechanisms that can detach a load and allow the UUV to float to the surface of the water. One embodiment is a recovery system for a UUV. The recovery system includes a detachable load that renders the UUV neutrally buoyant in water. The recovery system further includes a plurality of release mechanisms that detach the load to render the UUV positively buoyant in the water. The release mechanisms include a first, second, and third release mechanism. The first release mechanism detaches the load in response to a command signal. The second release mechanism detaches the load in response to the UUV being submerged in the water beyond a threshold time. The third release mechanism detaches the load in response to the UUV exceeding a maximum depth in the water. ## Claims ### Claim 1 A recovery system for an Unmanned Underwater Vehicle (UUV), the recovery system comprising: a detachable load that renders the UUV neutrally buoyant in water; and a plurality of release mechanisms configured to detach the load to render the UUV positively buoyant in the water, the release mechanisms comprising: a first release mechanism configured to detach the load in response to a command signal; a second release mechanism comprising a passive galvanic time-in-water release mechanism configured to detach the load in response to the UUV being submerged in the water beyond a threshold time; and a third release mechanism configured to detach the load in response to the UUV exceeding a maximum depth in the water. ### Claim 2 (depends on 1) The recovery system of claim 1 further comprising: a disk mechanically coupled to the load; wherein the plurality of release mechanisms are configured to detachably couple to the disk at substantially equidistant points around the disk. ### Claim 3 (depends on 2) The recovery system of claim 2 wherein: the disk is configured to tilt in response to at least one of the release mechanisms detaching from the disk, and to decouple from release mechanisms that remain coupled to the disk. ### Claim 4 (depends on 1) The recovery system of claim 1 wherein: the first release mechanism is configured to detach the load in response to a command signal from the UUV. ### Claim 5 (depends on 1) The recovery system of claim 1 wherein: the third release mechanism comprises a passive pressure-actuated release mechanism. ### Claim 6 (depends on 1) The recovery system of claim 1 wherein: the load comprises a portion of the UUV. ### Claim 7 (depends on 1) The recovery system of claim 1 wherein: the load comprises a drop weight. ### Claim 8 (depends on 1) The recovery system of claim 1 further comprising: a housing surrounding the release mechanisms; and a weight distribution plate mechanically coupled to the load; wherein the first release mechanism comprises: a first fixed arm coupled to the housing; a first movable arm that supports the weigh distribution plate in place relative to the first fixed arm; a first pin coupling the first fixed arm to the first movable arm; and an actuator coil detachably coupling the first movable arm to the first fixed arm and configured to allow the first movable arm to rotate at the first pin to remove support for the weight distribution plate in response to the command signal. ### Claim 9 (depends on 8) The recovery system of claim 8 wherein the second release mechanism comprises: a second fixed arm coupled to the housing; a second movable arm that supports the weight distribution plate in place relative to the second fixed arm; a second pin coupling the second fixed arm to the second movable arm; and a corrodible link detachably coupling the second movable arm to the second fixed arm and configured to allow the second movable arm to rotate at the second pin to remove support for the weight distribution plate in response to the UUV being submerged in the water beyond the threshold time. ### Claim 10 (depends on 9) The recovery system of claim 9 wherein the third release mechanism comprises: a third fixed arm coupled to the housing; a third movable arm that supports the weight distribution plate in place relative to the third fixed arm; a third pin coupling the third fixed arm to the third movable arm; and a burst plug detachably coupling the third movable arm to the third fixed arm and configured to allow the third movable arm to rotate at the third pin to remove support for the weight distribution plate in response to the UUV exceeding the maximum depth in the water. ### Claim 11 A recovery system for an Unmanned Underwater Vehicle (UUV), the recovery system comprising: a detachable load configured to render the UUV positively buoyant in water upon release; a first release mechanism configured to release the load from the UUV in response to a command signal; a second release mechanism comprising a passive galvanic time-in-water release mechanism configured to release the load from the UUV in response to the UUV being submerged in the water beyond a threshold time; and a third release mechanism configured to release the load from the UUV in response to the UUV exceeding a maximum depth in the water. ### Claim 12 (depends on 11) The recovery system of claim 11 wherein: the third release mechanism comprises a passive pressure-actuated release mechanism. ### Claim 13 (depends on 11) The recovery system of claim 11 wherein: the load comprises a portion of the UUV. ### Claim 14 (depends on 11) The recovery system of claim 11 wherein: the load comprises a drop weight. ### Claim 15 A method for operating a recovery system for an Unmanned Underwater Vehicle (UUV), the method comprising: affixing a detachable load that renders the UUV neutrally buoyant in water; detaching the load in response to a command signal to render the UUV positively buoyant in the water; detaching the load utilizing a passive galvanic time-in-water release mechanism in response to the UUV being submerged in the water beyond a threshold time to render the UUV positively buoyant in the water; and detaching the load in response to the UUV exceeding a maximum depth in the water to render the UUV positively buoyant in the water. ### Claim 16 (depends on 15) The method of claim 15 wherein: the load comprises a portion of the UUV. ### Claim 17 (depends on 15) The method of claim 15 wherein: the load comprises a drop weight. ### Claim 18 (depends on 15) The method of claim 15 wherein: the command signal comprises a signal generated by the UUV. ### Claim 19 A recovery system for an Unmanned Underwater Vehicle (UUV), the recovery system comprising: a detachable load that renders the UUV neutrally buoyant in water; a disk mechanically coupled to the load; and a plurality of release mechanisms configured to detach the load to render the UUV positively buoyant in the water, wherein the plurality of release mechanisms are configured to detachably couple to the disk at substantially equidistant points around the disk, the release mechanisms comprising: a first release mechanism configured to detach the load in response to a command signal; a second release mechanism configured to detach the load in response to the UUV being submerged in the water beyond a threshold time; and a third release mechanism configured to detach the load in response to the UUV exceeding a maximum depth in the water.