SYSTEM AND METHOD FOR POWER AND DATA TRANSMISSION IN A BODY OF WATER TO UNMANNED UNDERWATER VEHICLES

Abstract

A system for power and data transmission in a body of water to unmanned underwater vehicles comprises a floating surface station for generating electric energy and receiving and transmitting data; an underwater station connectable to at least one unmanned underwater vehicle; at least one submerged depth buoy; and an umbilical, which comprises a power transmission line and a data transmission line, is mechanically and electrically connected to the surface station and to the underwater station, and is mechanically coupled to the depth buoy so that the umbilical comprises a first umbilical section that is stretched between the underwater station and the depth buoy and a second umbilical section that extends loose between the depth buoy and the surface station.

Claims

1-18. (canceled)

19. A power and data transmission system comprising: a floating surface station configured to: generate electric energy, receive data, and transmit data; an underwater station; a depth buoy; an umbilical comprising a power transmission line and a data transmission line, the umbilical being mechanically and electrically connected to the floating surface station and to the underwater station, the umbilical being mechanically coupled to the depth buoy such that the umbilical comprises a first umbilical section that extends in a stretched configuration between the underwater station and the depth buoy and a second umbilical section that extends in a loose configuration between the depth buoy and the floating surface station; and a winch configured to selectively adjust a length of the first umbilical section and a depth of the depth buoy.

20. The power and data transmission system of claim 19, further comprising an unmanned underwater vehicle and a cable connected to the underwater station and to the unmanned underwater vehicle, the cable being configured for power transmission and data transmission to and from the underwater station.

21. The power and data transmission system of claim 19, wherein the floating surface station comprises a dynamic positioning device controlled to keep the second umbilical section in the loose configuration in different operational phases.

22. The power and data transmission system of claim 21, further comprising a control station configured to control, via the dynamic positioning device, a relative position between the floating surface station and the depth buoy.

23. The power and data transmission system of claim 22, wherein the control station is connected to the floating surface station by radio.

24. The power and data transmission system of claim 19, wherein the floating surface station comprises an antenna configured to transmit and receive data.

25. The power and data transmission system of claim 19, wherein the floating surface station comprises a power generation unit selected from any of: an endothermic engine coupled to an electric generator, a closed loop endothermic engine coupled to the electric generator, a fuel cell, a wind turbine, a solar cell, and a wave turbine.

26. The power and data transmission system of claim 19, further comprising a mechanical connector mounted at a bottom end of the umbilical and configured to mechanically connect the umbilical to the underwater station.

27. The power and data transmission system of claim 26, further comprising a ballast coupled to the bottom end of the umbilical.

28. The power and data transmission system of claim 19, wherein the depth buoy extends about the umbilical and is connected to the umbilical.

29. The power and data transmission system of claim 19, wherein the depth buoy comprises a connection point on a bottom side of the depth buoy.

30. The power and data transmission system of claim 19, wherein the depth buoy comprises a plurality of sleeves fitted to an intermediate umbilical section.

31. The power and data transmission system of claim 19, wherein the stretched configuration comprises the first umbilical section being maintained at a first tension and the loose configuration comprises the second umbilical section being maintained at a second, lesser tension.

32. A system comprising: a depth buoy; and an umbilical comprising a power transmission line and a data transmission line, the umbilical being mechanically and electrically connectable to a floating surface station configured to generate electric energy, receive data, and transmit data, the umbilical being mechanically and electrically connectable to an underwater station connectable to an unmanned underwater vehicle, the umbilical being mechanically coupleable to the depth buoy such that the umbilical comprises a first umbilical section that extends in a stretched configuration between the underwater station and the depth buoy and a second umbilical section that extends in a loose configuration between the depth buoy and the floating surface station; and a winch configured to selectively adjust a length of the first umbilical section and a depth of the depth buoy.

33. A method for power and data transmission in a body of water to an unmanned underwater vehicle, the method comprising: generating electric energy in a floating surface station; transferring power, via an umbilical, between the floating surface station and an underwater station; exchanging data, via the umbilical, between the floating surface station and the underwater station; stretching, via a depth buoy, a first section of the umbilical which extends between the underwater station and the depth buoy; keeping loose a second section of the umbilical section which extends between the depth buoy and the floating surface station; and selectively adjusting, via a winch, a length of the first section of the umbilical section and a depth of the depth buoy.

34. The method of claim 33, further comprising transferring power and data between the underwater station and the unmanned underwater vehicle.

35. The method of claim 33, further comprising controlling a position of the floating surface station by a dynamic positioning device to keep the second section of the umbilical loose in any operational phase.

36. The method of claim 35, further comprising: controlling the relative position between the floating surface station and the depth buoy, and actuating the dynamic positioning device as a function of said relative position.

37. The method of claim 33, further comprising selecting the length of the first section of the umbilical such that the depth buoy is located at a depth within the range between 40 meters and 70 meters.

38. The method of claim 33, further comprising selecting the length of the second section of the umbilical section such that the second section of the umbilical greater than the depth of the depth buoy.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0050] Further features and advantages of the present disclosure will be apparent from the following description of non-limiting embodiments thereof, with reference to the figures of the accompanying drawings, wherein:

[0051] FIG. 1 is a schematic view, with parts removed for clarity, of a system for power distribution and data transmission in a body of water for powering unmanned underwater vehicles in accordance with the present disclosure;

[0052] FIG. 2 is a perspective view, with parts removed for clarity, of an underwater station of the system according to the present disclosure;

[0053] FIG. 3 is a schematic, side elevation view, with parts removed for clarity, of a surface station of the system according to the present disclosure;

[0054] FIGS. 4 and 5 are perspective views, with parts removed for clarity, of respective variants of a detail of the system in FIG. 1;

[0055] FIG. 6 is a perspective view, with parts removed for clarity, of a detail of the system in FIG. 1; and

[0056] FIGS. 7 and 8 are perspective views, with parts removed for clarity, of respective variants of the detail in FIG. 6.

DETAILED DESCRIPTION

[0057] With reference to FIG. 1, a system 1 for power distribution and data transmission in a body of water is depicted as a whole. The system 1 comprises an underwater station 2; a surface station 3; at least one unmanned underwater vehicle 4; and an umbilical 5 mechanically and functionally connected to the underwater station 2 and the surface station 3. The system 1 is controlled by a control station 6, which, in FIG. 1, is arranged on board a support vessel 7.

[0058] In one variant (not shown), the control station is located on land.

[0059] The system 1 comprises a depth buoy 8, which is fixed to the umbilical 5 and arranged in the body of water between the underwater station 2 and the surface station 3 so that the umbilical 5 has a section 9, which extends between the underwater station 2 and the depth buoy 8, and a section 10, which extends between the depth buoy 8 and the surface station 3.

[0060] The underwater station 2 is installed on the bed of the body of water, whereas the surface station 3 is a floating station controlled by a dynamic positioning device 11, which enables the surface station 3 to be kept in a substantially stationary position and with a given or designated orientation. The dynamic positioning device 11 may comprise a satellite position detection system so as to maintain the surface station in a geostationary position, or may comprise a detection system configured to maintain the position of the surface station stationary with respect to other reference systems such as for example the depth buoy 8. The dynamic positioning device 11, in addition to the detection system, comprises adjustable screw propellers; and a control unit configured to control the power and orientation of the propellers according to the signals detected by the detection system.

[0061] The system 1 is configured to keep the first umbilical section 9 stretched at a controlled tension and the second umbilical section 10 relatively loose so as to follow the relative movements between the surface station 3 and the depth buoy 8 and avoid fatigue stresses on the umbilical 5 caused by weather and sea conditions.

[0062] In the illustrated case, the unmanned underwater vehicle 4 is a ROV connected to the underwater station 2 via a cable 12.

[0063] With reference to FIG. 2, the underwater station 2 has a support structure 13 configured to be laid on the bed of the body of water and to accommodate the unmanned underwater vehicle 4 in a specially provided charging station 14. The underwater station 2 comprises auxiliary, mechanical and electrical equipment 15; a coupling device 16 configured to mechanically connect the umbilical 5 to the underwater station 2, and electrical connection devices 17 and 18 to provide the power and data connection between the umbilical 5 and the underwater station 2.

[0064] With reference to FIG. 3, the surface station 3 comprises a support structure 19 and accommodates a power generation unit 20 configured to produce electric energy; an antenna 21 configured to receive and transmit data; and service equipment 22. In the illustrated case, the power generation unit 20 comprises an electrical generator driven by an endothermic engine and is housed in a semi-submerged hold of the surface station 3.

[0065] In accordance with alternative embodiments (not shown), the generator unit comprises fuel cells or a wind turbine or solar cells or a wave turbine.

[0066] With reference to FIG. 1, the umbilical 5 is configured to supply power and transmit data and is stably connected to the underwater station 2 and the surface station 3 so as to transmit the power generated in the surface station 3 to the connected users in the underwater station 2 and transmit data between the underwater station 2 and the surface station 3. For this purpose, the umbilical 5 comprises therein power lines and data lines (not shown in the attached Figures).

[0067] The depth buoy 8 extends about the umbilical 5 and is fastened to the umbilical 5.

[0068] FIG. 4 shows a depth buoy 23, which is a variant of the buoy 8 and is fastened to the umbilical 5. The buoy 23 has a connection point 24 for connection to the umbilical 5, at which point the umbilical 5 defines a curve. The umbilical sections 9 and 10 at the depth buoy 23 are associated with stiffening elements 25 in order to prevent the formation of folds in the umbilical 5.

[0069] FIG. 5 shows a depth buoy 26, which represents an alternative to the intermediate buoys 8 (FIGS. 1) and 23 (FIG. 4). The depth buoy 26 comprises a plurality of sleeves fitted and secured around the umbilical 5. The buoy 26 extends along an intermediate umbilical section 5 of considerable length interposed between the sections 9 and 10. The buoy 26 transmits a distributed load to the umbilical 5 and the intermediate section can assume a curved configuration.

[0070] With reference to FIG. 6, the bottom end of the umbilical 5 comprises a mechanical connector 27 configured to secure the umbilical 5 to the underwater station 2 (FIG. 1). The bottom end of the umbilical 5 is associated with a ballast 28, which in certain embodiments has a cylindrical shape and houses therein a junction box 29. The umbilical 5 is connected to the junction box from which a power terminal 30 and a data terminal 31 (in certain embodiments defined by a fiber-optic cable,) protrude. The umbilical 5 and the terminals 30 and 31 are protected by stiffening elements 25 at the junction box 29.

[0071] In use and with reference to FIG. 1, the surface station 3 generates electrical energy through the power generation unit 20 and exchanges signals with the control station 6 via the antenna 21. The surface station 3 is mechanically and functionally connected to the umbilical 5, which transmits energy and exchanges data with the underwater station 2, which in tum is connected to the unmanned underwater vehicle 4 in order to supply energy and exchange data.

[0072] The umbilical section 9 is kept stretched by the depth buoy 8. The length of the umbilical section 9 is selected so that the depth buoy 8 is located at a depth within the range between 70 and 30 meters lower than the surface of the body of water. The length of the umbilical section 10 is selected so that the umbilical section is considerably greater than the depth of the buoy 8, to enable relative misalignments between the depth buoy 8 and the surface station 3 with respect to a vertical direction, and distance variations between the depth buoy 8 and the surface station 3. In other words, the weather and sea conditions, such as wave motion, currents and tides, can cause relative displacements between the surface station 3 and the depth buoy 8. These weather and sea phenomena are typically variable near the surface of the body of water.

[0073] The dynamic positioning device 11 of the surface station 3 in any case maintains the surface station 3 in the vicinity of the depth buoy 8 so as to keep the umbilical section 10 relatively loose and enable relative displacements between the depth buoy 8 and the surface station 3 without subjecting the umbilical section 10 to tensile and torsional stress.

[0074] The operation of the system 1 does not change as a function of the type of depth buoy used. In other words, the system 1 may be equipped with a depth buoy 8 or a depth buoy 23 or a depth buoy 26, without changing the mode of operation.

[0075] With reference to the variant in FIG. 7, the bottom part of the umbilical 5 comprises a mechanical connector 32 configured to secure the umbilical 5 to the underwater station 2 (FIG. 1). In the illustrated case, the mechanical connector 32 is associated with a winch 33 around which an end umbilical section 34 is wound. The winch 33 has a frame 35 and a spool 36 supported by the frame 35 so that it can selectively rotate about an axis Al and, if sufficiently heavy, may also serve as a ballast. The winch 33 houses therein a junction box (not shown in the attached Figures) from which a power terminal and a data terminal (also not shown in the attached Figures) protrude, which are connected to two connectors 37 and 38, respectively, arranged along the spool 36.

[0076] In use of certain embodiments, the winch 33 is housed within the underwater station 2 (FIG. 1) and in such a way that the useful length of the umbilical 5 can be adjusted, and the length of the umbilical section 9 and the depth of the depth buoy 8 can be determined (FIG. 1).

[0077] The winch 39 shown in FIG. 8 is a variant of the winch 33 shown in FIG. 7 and differs from the latter in that the center of gravity of the winch 39 is aligned with the axis of the deployed umbilical.

[0078] It is clear that the present disclosure includes further variants that are not explicitly described, without however departing from the scope of protection of the following claims. Accordingly, various changes and modifications to the presently disclosed embodiments will be apparent to those skilled in the art.