Towed underwater vehicle and system for recovering such an underwater vehicle

Abstract

The invention relates to an underwater vehicle (100) comprising a hull (110) extending along a longitudinal main axis (155) between a first end and a second end opposite the first end, a fastening member (175) situated at the first end of the hull and configured to cooperate with a towing cable (170) in order to allow the vehicle to be towed from the vessel, a gripper (140) situated at the second end of the hull and configured to adopt an open position or a closed position, a detection member (150) and a guide member which are configured respectively to detect a recovery cable and to guide the vehicle so that the gripper in the open position engages with the recovery cable; by virtue of which the vehicle can be recovered or launched from the vessel by means of the fastening member and the gripper, which cooperate respectively with the towing cable and the recovery cable.

Description

[0001] TITLE: Underwater towed vehicle and recovery system for such an underwater vehicle

[0002] Technical field of the invention

[0003] The present invention relates to underwater vehicles towed from a vessel, better known by the acronym TUV meaning "Towed Underwater Vehicle", and to recovery systems for such underwater vehicles.

[0004] State of the art

[0005] There are various systems known for launching and retrieving underwater vehicles towed from a ship, known as TUVs.

[0006] For example, the TUV is connected to a so-called towing cable, capable of towing the TUV from a ship.

[0007] The towing cable is connected at one end to the TUV, and at the other end to a winch which is generally secured to the vessel and which is operable to pay out and rewind the cable respectively to launch and recover the TUV or, in other words, to move the TUV away from and towards the vessel.

[0008] To retrieve the TUV, i.e., to extract it from the water and bring it back on board the vessel, the system can be provided with a ramp movably mounted on the vessel. The TUV is winched onto the ramp deployed from the vessel, and then the ramp is retracted onto the vessel so as to hoist the TUV on board the vessel.

[0009] Alternatively, the recovery system can be fitted with a cage. The TUV is then winched into the cage, which is submerged, and then the cage is hoisted with the TUV onto the vessel using a davit or a crane equipped with a winch.

[0010] Statement of the invention

[0011] The invention aims to provide an underwater vehicle configured to be towed from a ship, which is particularly simple and convenient to recover.

[0012] The invention thus relates, in a first aspect, to an underwater vehicle configured to be towed and recovered and / or launched from a ship, comprising a hull extending along a longitudinal main axis between a first end and a second end opposite the first end, the vehicle comprising an attachment member, located on the side of the first end of the hull, capable of cooperating with a towing cable to allow the vehicle to be towed from the ship; characterized in that it comprises a clamp located on the side of the second end of the hull and configured to take an open position or a closed position, a detection member and a guide member respectively configured to detect a recovery cable and to guide the vehicle so that the clamp in the open position engages with the recovery cable;whereby the vehicle can be recovered or launched from the vessel by means of the attachment member on the one hand, and the clamp on the other hand, respectively in cooperation with the towing cable on the one hand and the recovery cable on the other hand.;

[0013] Such a vehicle of the towed or towed type can, thanks to the clamp and the guidance and detection devices, be extracted from the water autonomously by means of a recovery cable fitted to a reception platform placed out of the water, for example on a ship or on the pontoon of a port.

[0014] In addition to the attachment member by which the vehicle is towed, the vehicle includes a clamp which forms a gripping means configured to engage a recovery cable using the detection member and the guide member.

[0015] Thus, the tow cable and the recovery cable are connected to the docking platform and allow the vehicle to be extracted from the water and placed on the docking platform.

[0016] In the vehicle, the attachment device and the clamp allow the vehicle to be secured to a docking platform in order to extract the vehicle from the water using towing and recovery cables.

[0017] Other particularly simple and convenient features of the vehicle according to the invention are described below.

[0018] The vehicle may include a first control unit configured to operate the clamp from the open position to the closed position, and vice versa.

[0019] The guidance member may include a second control unit configured to receive detection information provided by the detection member and guide the vehicle toward the recovery cable detected by the detection member.

[0020] Such a control unit is thus provided to control and synchronize the action of the detection and guidance members in order to ensure that the clamp engages with the recovery cable.

[0021] The detection member may include a forward sonar located on the side of the second end of the vehicle hull, and configured to detect a cable near the second end of the vehicle hull.

[0022] Such a sonar makes it possible, during navigation, to identify submerged recovery cables. Depending on the direction in which the recovery cable was detected by the sonar, the guidance member then guides the vehicle in their direction, preferably in their alignment, to allow the clamp to cooperate with the recovery cable.

[0023] The vehicle may further comprise, projecting from the hull, one or more fins which can be oriented and controlled by means of the guide member.The invention also relates, in a second aspect, to a recovery system comprising an underwater vehicle as described above and a reception platform, said reception platform comprising a recovery cable having, at a free end, a retaining member, a towing cable fixed at one end to the attachment member of the vehicle, a winching mechanism configured to respectively wind and unwind said recovery and towing cables, and the recovery system is configured so that the clamp, in the open position, engages with the recovery cable and cooperates, in the closed position, with the retention member of the recovery cable; whereby the vehicle can be recovered or launched from the reception platform by actuating the winching mechanism and by means of the attachment member and the clamp which are respectively in cooperation with the towing cable and the recovery cable.

[0024] Such a recovery system makes it possible, through the cooperation of the recovery cable and the retaining member and through the cooperation of the towing cable and the attachment member, and by actuating the winching mechanism, to reduce the length of the cables and to remove the autonomous underwater vehicle from the water, to place it on a reception platform.

[0025] The docking platform may further include a third control unit configured to operate the winching mechanism.

[0026] The docking platform and the underwater vehicle may each include a communication unit configured to synchronize the actuation of the detection and guidance members and the winching mechanism.

[0027] Such a recovery system can thus be automated. Communication between the docking platform and the underwater vehicle allows the control units to be synchronized to ensure that the clamp is closed around the recovery cable before the winching mechanism is activated to reduce the cable length, and thus extract the vehicle from the water.

[0028] The docking platform can be embarked on a ship.

[0029] The invention also relates, in a third aspect, to a method for recovering an underwater vehicle by means of a recovery system as described above, comprising the following navigation steps:

[0030] - detecting, via the detection device, a recovery cable from the reception platform;

[0031] - operate the underwater vehicle clamp from the closed position to the open position of the clamp;

[0032] - guiding the underwater vehicle by means of the guide member towards the recovery cable so that the recovery cable is housed in the open clamp; - operating the clamp of the underwater vehicle from the open position to the closed position;

[0033] - operate the winch mechanism to raise the underwater vehicle.

[0034] Brief description of the figures

[0035] The invention, according to an exemplary embodiment, will be well understood and its advantages will appear better on reading the detailed description which follows, given for information purposes and in no way limiting, with reference to the appended drawings in which:

[0036] Figure 1 shows schematically and in profile view an underwater vehicle towed from a ship, also called TUV, in accordance with the invention.

[0037] Figure 2 shows schematically and in bottom view the TUV of Figure 1.

[0038] Figure 3 schematically represents, in profile view, a step of recovery of the TUV of figures 1 and 2 using a reception platform arranged on board a ship, the platform and the TUV together forming a recovery system according to a first embodiment.

[0039] Figure 4 is a view similar to Figure 3, showing another recovery step.

[0040] Figure 5 is a view similar to Figures 3 and 4, showing yet another recovery step.

[0041] Figure 6 is a view similar to Figures 3 to 5, but in perspective and showing yet another recovery step.

[0042] Figure 7 shows a side view of the recovery system comprising the TUV illustrated in Figures 1 and 2 and a reception platform according to an alternative embodiment.

[0043] Detailed description

[0044] Identical elements shown in the above figures are identified by identical reference numerals in the following.

[0045] The invention finds an application in the field of towed or pulled underwater vehicles, known under the term TUV, as specified above.

[0046] TUVs are used to carry out various operations at sea, such as surveillance operations.

[0047] For this purpose, underwater vehicles are launched from a ship, for example USV boats, in English "Unmanned Surface Vessel", and are towed, completely submerged in the water in a nominal position.

[0048] Once the operations are completed, the TUV is recovered and reassembled on board the ship.

[0049] An example of an underwater vehicle of the TUV 100 type capable of being towed at sea is illustrated in Figures 1 and 2. In the remainder of the description, the terms vehicle, underwater vehicle and TUV are used interchangeably to designate a towable or towable underwater vehicle.

[0050] The TUV 100 is illustrated in Figures 1 and 2 in the nominal navigational position, when towed, in which the longitudinal main axis 155 is substantially parallel to the horizontal axis.

[0051] In the remainder of the description, by horizontal plane is meant a plane having an orientation substantially parallel to the horizon.

[0052] The TUV 100 comprises a shell 110, of generally cylindrical shape.

[0053] Alternatively, the vehicle body could be of any other shape.

[0054] This shell 110 extends along a main longitudinal axis 155 between a first end, called the front end, and a second end, called the rear end.

[0055] The TUV 100 has a 120 nose at the front end and a 130 tail at the rear end opposite the front end.

[0056] In the nominal navigation position, the hull 110 comprises an upper portion 110a facing the sea surface when the TUV 100 is submerged at sea and towed by the vessel, and a lower portion 110b facing the seabed when the TUV 100 is submerged at sea and towed by the vessel.

[0057] The shell 110 further comprises side portions, including a first side portion 110c and a second side portion 110d.

[0058] The lateral parts 110c, 110d are thus arranged on either side of the longitudinal axis 155 and connect the upper part 110a to the lower part 110b of the shell 110.

[0059] The TUV 100 may comprise, on the lateral portions 110c and 110d of the shell 110, fins 115a, 115b, 115c and 115d formed projecting from the shell 110 and extending along an axis forming an angle with the longitudinal axis 155.

[0060] The fins 115a, 115b, 115c and 115d can be fixed or movable.

[0061] When they are movable, the orientation of the fins relative to the longitudinal axis 155 can for example be modified.

[0062] In the illustrated example, the TUV 100 comprises two pairs of fins, respectively the fins 115a and 115b and the fins 115c and 115d. The fins 115a, 115b and 115c, 115d of these pairs are thus arranged on the hull 110 on either side of the longitudinal axis 155, in other words to starboard and to port, here in a substantially symmetrical manner.

[0063] Alternatively, the TUV 100 may comprise a single pair of fins, for example fins 115a and 115b, or conversely only fins 115c and 115d.

[0064] Of course, other arrangements of fins 115a, 115b and 115c, 115d can be envisaged.

[0065] The fins make it possible to modify the trajectory of the TUV 100 when it is sailing. On the upper part 110a of the hull 110, the TUV 100 further comprises an attachment member 175, configured to allow the TUV 100 to be towed at sea. In particular, the attachment member 175 is located on the side of one end of the hull 110, for example near the nose 120 of the TUV 100.

[0066] Alternatively, the attachment member 175 may be disposed on other parts of the shell 110.

[0067] The TUV 100 further comprises a clamp 140 on the hull 110, for example on the tail side 130 of the TUV 100.

[0068] The clamp 140 forms a gripping means capable of taking several configurations.

[0069] The clamp 140 may comprise two branches 140a, 140b mounted articulated and projecting from the shell 110.

[0070] The branches 140a, 140b can be movable in rotation, for example symmetrically, around an axis orthogonal to the longitudinal axis 155.

[0071] The gripper 140 may be configured to adopt a navigation configuration in which the arms 140a, 140b of the gripper 140 are arranged so as to be in contact with the side portions 110c, 110d of the hull 110.

[0072] In this navigation configuration, the arms 140a, 140b do not protrude from the hull 110.

[0073] The gripper 140 may be configured to also adopt a throwing and / or retrieving configuration in which the arms 140a, 140b of the gripper 140 are configured to assume different positions.

[0074] In particular, in the launching and / or retrieving configuration of the gripper 140, the arms 140a, 140b may be in an open position in which the arms 140a, 140b are apart and define an open space; or in a closed position in which the arms 140a, 140b are close together and define a generally closed space.

[0075] In this launch and / or recovery configuration of the clamp 140, the arms 140a, 140b are arranged to project relative to the shell 110.

[0076] The clamp 140 and the attachment member 175 may be arranged respectively at opposite ends of the TUV 100.

[0077] For example, the clamp 140 may be disposed on the tail 130 side of the TUV 100 and the attachment member 175 may be disposed on the nose 120 side of the TUV.

[0078] The clamp 140 and the attachment member 175 may be substantially aligned with the longitudinal axis of the TUV 100.

[0079] The TUV 100 comprises means for actuating the clamp 140. For example, the TUV 100 may comprise a first control unit 180 configured to actuate the clamp 140, so that it takes a position conforming to one of the configurations detailed previously.

[0080] The TUV 100 further comprises a detection member 150 configured to detect elements present in the environment in which the TUV 100 operates.

[0081] The detection member 150 is arranged on the side of the rear end of the TUV 100, for example towards the tail 130, to detect objects downstream of the rear end of the hull 110.

[0082] The detection member 150 may be, for example, a forward sonar configured to detect objects underwater and which is configured to indicate their direction and their distance relative to the TUV 100.

[0083] The TUV 100 further includes a guidance member configured to guide the TUV 100 as it navigates.

[0084] The guidance member may comprise a second control unit 185, configured to guide the TUV 100 according to detection information provided by the detection member 150.

[0085] The guide member may, for example, allow some or all of the fins 115a, 115b, 115c and 115d to be controlled to guide the TUV 100.

[0086] The guidance organ can also be used to control any means of the TUV 100 allowing it to change its trajectory when navigating.

[0087] The TUV 100 may include a communication module 190 configured to exchange information with another entity, such as a vessel, so as to synchronize actions between the TUV 100 and the vessel.

[0088] A recovery system 205 of a TUV 100 is now described with reference to Figures 3 to 6.

[0089] The recovery system 205 is formed of the TUV 100 as described with reference to FIGS. 1 and 2 and a reception platform 200 arranged on a ship 210.

[0090] The ship 210 extends longitudinally along the horizontal axis 280a of the reference frame 280, between a front part 210a and a rear part 210b.

[0091] In a nominal direction of travel, indicated by the arrow 310, the front part of the ship 210 moves upstream of the rear part of the ship 210.

[0092] The front 210a and rear 210b portions of the ship 210 are connected to each other by side portions.

[0093] The reception platform 200 comprises a first cable 230, also called a recovery cable, and a second cable 170, also called a towing cable. The recovery cable 230 comprises at one of its free ends a retaining member 240.

[0094] This retaining member 240 is for example a pig, that is to say a mass.

[0095] The towing cable 170 makes it possible to secure the TUV 100 to the ship, by means of the attachment member 175.

[0096] The attachment member 175 may allow the towing cable 170 to be removably attached.

[0097] The first and second cables 170, 230 are configured to be deployed and at least partially submerged at sea.

[0098] For this, the first and second cables 170, 230 are respectively connected to a winching mechanism configured to wind and unwind the cables 230 and 232.

[0099] The winching mechanism may be arranged on a rear portion of the vessel 210.

[0100] The winching mechanism may comprise two winches 220, 225.

[0101] The winches 220, 225 are here respectively associated with return pulleys 260, 265.

[0102] The return pulleys 260, 265 are spaced apart by a distance D along the horizontal axis 280a of the reference frame 280, substantially parallel to the horizon.

[0103] The distance D is substantially equal to the distance between the clamp 140 and the attachment member 175 of the TUV 100.

[0104] Alternatively, the winching mechanism may be without return pulleys.

[0105] The vessel 210 includes means for actuating the winching mechanism.

[0106] For example, the vessel 210 may include a third control unit 215, configured to operate the winching mechanism, in order to extract or immerse the first and second cables 230, 170 in the water, by winding them up or unwinding them.

[0107] The reception platform 200 may also comprise a protective panel 250 arranged between the two winches 220, 225 or between the two return pulleys 260, 265.

[0108] The protective panel 250 may be made, for example, of foam, or of any other material capable of absorbing shocks.

[0109] The reception platform 200 further comprises a communication module 245 capable of exchanging information with the communication module 190 of the TUV 100.

[0110] The operation of the recovery system is now described with reference to the steps illustrated in Figures 3 to 6.

[0111] Figure 3 illustrates the recovery system 205 in navigation configuration.

[0112] In this configuration, the TUV 100 is towed by the nose 120 by the vessel 210, both moving in the direction indicated by the arrow 310. The clamp 140 of the TUV is operated in the navigation configuration, for hydrodynamic reasons.

[0113] The towing cable 170, connected to the TUV by the attachment member 175, is at least partially deployed, so that the TUV 100 is fully submerged in the water and towed underwater by the vessel 210.

[0114] During navigation, the recovery cable 230 can be completely extracted from the water and is only deployed during the recovery phases of the TUV 100.

[0115] When a recovery phase is initiated, the recovery system 205 is then in the configuration illustrated in FIG. 4, in which the clamp 140 of the TUV 100 is in the open position and the recovery cable 230 of the docking platform 200 is deployed.

[0116] The TUV 100 then detects, via the detection member 150, the recovery cable 230 of the reception platform 200.

[0117] Once the recovery cable 230 has been detected, the information relating to its detection is sent to the guidance member, i.e. to the second control unit 185 of the TUV 100, to guide the TUV 100 close to the recovery cable 230.

[0118] For this, the second control unit 185 can be configured to actuate one or more fins 115a, 115b, 115c and 115d of the TUV 100.

[0119] The second control unit 185 may be configured to operate the winching mechanism to vary the length of the tow cable 170 to bring the TUV closer to the recovery cable 230.

[0120] For example, the second control unit 185 can communicate with the reception platform 200 via the communication modules 190, 245, in particular to request from the third control unit 215 the actuation of the winching mechanism to lengthen or shorten the towing cable 170.

[0121] Optionally, before guiding the TUV 100 near the recovery cable 230, the second control unit 185 can obtain confirmation from the third control unit 215 and via the communication modules 190, 245, that the detected cable is indeed the recovery cable 230 of the vessel 210.

[0122] Thus, the guide member, and therefore the second control unit 185, guides the TUV 100 towards the recovery cable 230 so that the recovery cable 230 is housed in the open clamp 140.

[0123] Once the recovery cable 230 is placed inside the clamp 140, the first control unit 180 actuates the clamp 140 to place it in the closed position.

[0124] For example, detectors capable of detecting the presence of a cable are arranged on the clamp 140, for example on one of the arms 140a, 140b. Such detectors are connected to the first control unit 180 and can allow the triggering of the actuation of the clamp 140 in the closed position.

[0125] The recovery system 205 is then in the position illustrated in Figure 5.

[0126] In this position, the TUV 100 can in particular send information to the reception platform 200, via the communication modules 190, 245, in order to indicate that it is ready to be recovered, and therefore to be extracted from the water.

[0127] Alternatively, the information may be transmitted via the second cable 170.

[0128] The winches 220, 225 are then operated to wind the first and second cables 170 and 230 so as to reduce their deployed length, as indicated by the arrows 280.

[0129] Thus, the progressive winding of the cables 230 and 170 is done until the recovery system is in the configuration illustrated in Figure 6.

[0130] In this configuration, the TUV 100 is secured to the reception platform 200.

[0131] This is made possible in particular thanks to the cooperation of the retaining member 240 with the clamp 140 and thanks to the attachment member 175 securing the towing cable 170 with the TUV 100.

[0132] Once the retaining member 240 is in abutment against the clamp 140, the action of the winches 220, 225 via the cables 230, 170 makes it possible to gradually extract the TUV 100 from the water.

[0133] The ascent of the TUV 100 is thus stable, in particular due to the position of the clamp 140 and the attachment member 175, respectively at the front and rear of the TUV 100.

[0134] To prevent damage to the TUV 100 during ascent, the protection panel 250 is mounted between the two return pulleys 260 and 265, opposite the upper part of the TUV 100.

[0135] The TUV 100 can be reassembled and pressed against the protective panel 250 when it is positioned, after recovery, on the reception platform 200.

[0136] This 205 recovery system can also be reused to launch the TUV 100.

[0137] For this, once the reception platform 200 is placed in a launching area, the winches 220, 225 are activated by means of the third control unit 215, to gradually unwind the cables 170, 230 and to submerge the TUV 100.

[0138] Once at the desired launch depth, which can be indicated by the docking platform to the TUV 100 via the communication modules 190, 245 of the docking platform 200 and the TUV 100, the control unit of the TUV 100 actuates the clamp 140 in order to open it.

[0139] The guide member can then guide the TUV 100 to extract the recovery cable 230 from the clamp 140, for example by means of different maneuvers.

[0140] The clamp 140 can also be actuated to assume the navigation position, then releasing the recovery cable 230.

[0141] Recovery and launch operations can be carried out while the vessel 210 is in motion.

[0142] An alternative embodiment of a recovery system 300 is illustrated in Figure 7.

[0143] The winches 220, 225 of the recovery system 300 may be disposed on a lateral side, port or starboard, of the vessel 210 rather than aft.

[0144] The winches 220, 225 may be spaced apart by a distance D defined along the axis 280a of the reference frame 280 of Figure 7, which is for example equal to the distance between the clamp 140 and the attachment member 175.

[0145] The winches 220, 225 may further be spaced apart by a distance defined along the axis 280c and which is substantially equal to the greatest width of the hull of the TUV 100, i.e. the maximum dimension of the hull according to a cross-section at the longitudinal axis 155.

[0146] In a variant not illustrated, the clamp may admit other configurations and / or the arms of the clamp may be in other positions than those defined above.

[0147] The clamp may also have structural characteristics different from those described above.

[0148] For example, the clamp may comprise a single arm securely attached and hinged to a side portion of the hull on one end of the hull, for example located on the tail side.

[0149] The arm is then movable between at least two positions, including a first position in which the arm forms a non-zero angle with the lateral part of the hull, and defines an open space with the hull; and a second position in which the arm is positioned substantially parallel to the hull, for example, partially in contact with the hull, so as to no longer delimit an open space with the hull.

[0150] In a variant not illustrated, the first and second control units may be formed only of a control module which ensures the functions of each of these units described above; and / or the communication module may be included in the second control unit, or even in the control module.

[0151] It is recalled more generally that the invention is not limited to the examples described and represented.

Claims

CLAIMS 1. An underwater vehicle configured to be towed and recovered and / or launched from a vessel, comprising a hull (110) extending along a longitudinal main axis (155) between a first end and a second end opposite the first end, an attachment member (175) located on the side of the first end of the hull and configured to cooperate with a towing cable (170) to allow the vehicle to be towed from the vessel; characterized in that it comprises a clamp (140) located on the side of the second end of the hull and configured to take an open position or a closed position, a detection member (150) and a guide member respectively configured to detect a recovery cable (230) and to guide the vehicle so that the clamp in the open position engages with the recovery cable;whereby the vehicle (100) can be recovered or launched from the vessel by means of the attachment member and the clamp which are respectively in cooperation with the towing cable and the recovery cable.; 2. Underwater vehicle according to claim 1, comprising a first control unit (180) configured to actuate the clamp (140) from the open position to the closed position, and vice versa.

3. Underwater vehicle according to one of claims 1 and 2, wherein the guidance member comprises a second control unit (185) configured to receive detection information provided by the detection member (150) and guide the vehicle (100) towards the recovery cable (230) detected by the detection member.

4. An underwater vehicle according to any one of claims 1 to 3, wherein the detection member (150) comprises a front sonar located on the side of the second end of the hull of the vehicle and which is configured to detect a cable near the second end of the hull of the vehicle.

5. Underwater vehicle according to any one of claims 1 to 4, comprising one or more fins (115a-d) located projecting from the hull (110) and orientable and controllable by means of the guide member.

6. Recovery system comprising an underwater vehicle (100) according to any one of claims 1 to 5 and a reception platform (200), said reception platform comprising a recovery cable having at a free end a retaining member (240), a towing cable fixed at one end to an attachment member (175) of the vehicle, a winching mechanism configured to respectively wind and unwind said recovery and towing cables, and the recovery system (205) is configured so that the clamp, in the open position, engages the recovery cable and cooperates, in the closed position, with the recovery cable retaining member; whereby the vehicle can be recovered or launched from the reception platform by actuating the winching mechanism and by means of the attachment member and the clamp which are respectively in cooperation with the towing cable and the recovery cable.

7. The recovery system of claim 6, wherein the docking platform (200) comprises a third control unit (215) configured to operate the winching mechanism.

8. Recovery system according to one of claims 6 and 7, in which the reception platform (200) and the underwater vehicle (100) each comprise a communication unit (190) configured to synchronize the actuation of the detection and guidance members and the winching mechanism.

9. Recovery system according to any one of claims 6 to 8, in which the reception platform (200) is embarked on a ship (210).

10. A method of recovering an underwater vehicle by means of a recovery system (205) according to any one of claims 6 to 9, comprising the following navigation steps: detecting by means of the detection member a recovery cable of the reception platform; actuating the clamp of the underwater vehicle from the closed position to the open position of the clamp; guiding the underwater vehicle by means of the guiding member towards the recovery cable so that the recovery cable is housed in the open clamp; actuating the clamp of the underwater vehicle from the open position to the closed position; actuating the winching mechanism to raise the underwater vehicle.

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