Patent Description:
Underwater vehicles are used for a wide variety of operations that include - but are not limited to inspection/identification, oceanography, survey missions or samples picking. Underwater vehicles may be manned or unmanned. Among the unmanned vehicles, there are ROVs and AUVs. An Autonomous Underwater Vehicle (AUV) is a robot that travels underwater without requiring input from an operator. AUVs constitute part of a larger group of undersea systems known as unmanned underwater vehicles, a classification that includes the mentioned non-autonomous Remotely Operated underwater Vehicles (ROVs) - controlled and powered from the surface by an operator/pilot via an umbilical or using remote control. ROVs are unmanned underwater vehicles connected to a base station, which may be a ship. As mentioned ROVs are connected to the ship by means of cables; this implies that the maximum achievable distance between the ROV and the base station is limited by the length of the cable. AUVs are unmanned underwater vehicles, which are connected to a docking station by means of a wireless communication. Typically, AUVs are propelled through the energy stored in batteries housed in their body. This means that the operative range of an AUV is limited by the capacity of the battery.

This type of underwater vehicles has recently become an attractive alternative for underwater search and exploration since they are cheaper than manned vehicles. Over the past years, there have been abundant attempts to develop underwater vehicles to meet the challenge of exploration and extraction programs in the oceans. Recently, researchers have focused on the development of AUVs for long-term data collection in oceanography and coastal management. The oil and gas industry uses AUVs to make detailed maps of the seafloor before they start building subsea infrastructure; pipelines and sub-sea completions can be installed in the most cost effective manner with minimum disruption to the environment. The AUV allows survey companies to conduct precise surveys of areas where traditional bathymetric surveys would be less effective or too costly. In addition, post-lay pipe surveys are now possible, which includes pipeline inspection. The use of AUVs for pipeline inspection and inspection of underwater man-made structures is becoming more common.

With the adoption of AUV technology becoming more widespread, the limitations of the technology are being explored and addressed. The average AUV charge lasts about <NUM>-hours on an underwater AUV, but sometimes it is necessary to deploy them for the kinds of several day missions that some unmanned systems are equipped to undertake. Like most robots, the unmanned mechanisms contain batteries that require regular recharging. Docking stations that communicate directly with underwater vehicles, guiding them to where they can recharge and transfer data have been developed. Any data the AUV has gathered, such as images of the seabed, could be uploaded to the docking station and transmitted to home base, which could direct new instructions to the robot.

It is known from <CIT>a subsea basket or garage for unmanned underwater vehicles or UUVs, especially autonomous underwater vehicles or AUVs. A basket for hosting an AUV on the seabed comprises a hollow open-topped body. The body surrounds a receptacle into which an AUV that enters the body through the open top can dock for protection, recharging, data download and/or data upload for reprogramming. The open top of the body is closed by a lid movable between a closed and an open position. When the lid is open, an AUV can access the receptacle by moving generally horizontally to under the lid before lowering through the open top of the body and into the receptacle for docking. The lid is then closed onto the body over the docked AUV. The lid is supported and moved by telescopic guideposts driven by actuators that extend vertically from the body to lift the lid into the open position and retract vertically to lower the lid into the closed position. In another embodiment, paired posts may be stowed against opposed sloping sides of the body lying compactly against those sides. When deployed, the posts swing into deployed positions in opposite angular directions about respective pivot axes that are parallel to the respective sides of the body; the posts are part of a lifting frame that further comprises a crossbar in two sections. A respective section of the crossbar is attached to each post such that, when deployed, the sections of the crossbar extend oppositely and orthogonally with respect to the associated posts. Pivots between each post and the attached section of the crossbar allow the sections of the crossbar to collapse compactly against the sloping sides of the body when the posts are stowed away. This prior art does not focus on data exchange between the station and the AUV, but rather defines a complex structure to house and protect the AUV during data exchange and power recharging. However, the proposed structure with several moving parts is complex and may not be really effective. Further, the docking station is designed for very specific and dedicated AUVs.

In addition to the above, any underwater vehicle requiring the need of a wireless communication with the docking station faces at least the problem of the limitations for wireless communications in water. Radio frequencies are significantly attenuated in water. Above some hundreds of KHz, in particular, above <NUM>, attenuation in water raises significantly and any communication is affected by a link budget loss that limits the communication to some meters or less even with relevant transmission power and antenna gains. In particular, above <NUM> attenuation in seawater raises with a more than linear law from 30dB/m to reach about 60dB/m at frequencies of about <NUM>. Lower frequencies, that lay between the ELF (<NUM>-<NUM>) up to the LF (<NUM> - <NUM>) band, and that include acoustic and/or ultrasonic frequencies, are significantly less attenuated in water.

Exploiting low frequencies for signal transmission implies significant limitations in bandwidth, which may be so reduced that even the voice may have some problem to be transmitted. In practice, with LF frequencies transmissions can take place at some hundreds of meters, while ELF transmissions can be effectively performed at longer distances.

Underwater wireless communication may be performed by means of an optical communication system. Optical communication is affected by water turbidity, and the performance of an effective communication is affected by the type of modulation used for the optical radiation. In any case, it is known that through the optical communications some tens of meters at most can be reached in seawater. Optical communication, due to the high frequency of the carrier(s), provides high bandwidth that allows providing video streaming and/or high-definition images transmission with low latencies.

The Applicant further notices that an effective control of complex underwater vehicles necessitates a predetermined communication structure. An improved docking station appears necessary to allow AUV data collection efficiently, to permit reliable commands exchange, AUVs recharging and control. Further, an easily configurable docking station is desirable for coupling and interaction with different type of underwater devices.

The purpose of the present disclosure is to provide an underwater docking station for communication with one or more underwater devices configured to overcome the aforementioned drawbacks.

One aim of the disclosure is to allow flexibility in submarine communication with a variety of different submarine devices that can be configured and housed in or at the docking station.

A further purpose of the invention is to allow rapid configuration between different operating positions of the docking station to not only accommodate and hold an AUV in place, but also to be able to receive, and (e.g., mechanically) couple and communicate with a ROV, and possibly interact with both devices simultaneously.

A further aim is to allow communication with the underwater device(s) over long distances and/or with sufficient bandwidth and to allow data transfer at high speed (e.g., video data transfer), too.

An auxiliary aim is to provide a docking station that may be easily reconfigured for mechanically and/or communicatively coupling with different AUVs and/or ROVs.

These and further purposes of the present disclosure are obtained by means of an underwater docking station for communication with one or more underwater devices as here disclosed.

In the subsequent detailed description, a preferred embodiment of the underwater docking station according to the present disclosure will be presented. The detailed description refers to the annexed figures; a brief description thereof is here presented.

<FIG> represents an underwater docking station <NUM> designed for communication with one or more underwater devices <NUM> (or underwater vehicles such as AUVs and/or ROVs). Though not limiting, the underwater docking station <NUM> is primarily a seabed underwater docking station, namely a station that, when operative, is positioned and lies on the seafloor. In this regard, the underwater docking station <NUM> is designed to resist to water pressure and to water salinity and may also operate at great depths such as <NUM> metres below sea level.

The underwater docking station <NUM> comprises a support structure <NUM> that defines the frame containing the 'operative' elements of the docking station <NUM> further allowing the station <NUM> itself to rest on the seabed. The support structure <NUM> includes a base portion 2a and a top portion 2b interconnected one another.

The portion 2a includes a support plate <NUM> that is substantially flat for resting on the seabed; the support plate may have any suitable overall dimension, however a length of less than <NUM> (for example a length of about <NUM>) and a width of less than <NUM> (for example a width of about <NUM>) may be recommended to keep the overall volume sufficiently reduced. The support plate <NUM> may be rectangular with a ratio of sides between <NUM> and <NUM> (width/length).

As apparent from the figures (for example <FIG>), the support plate <NUM> has a grid structure showing a plurality of lightening holes of e.g., rectangular form. The holes not only reduce the station weight, but also allow a more stable resting on the seabed since ground irregularities may be compensated.

As shown in <FIG> and <FIG>, the support structure <NUM> comprises a mechanism <NUM> interposed between the base portion 2a and the top portion 2b to allow moving the base portion 2a away from the top portion 2b defining an housing space <NUM> for receiving the underwater device <NUM> between the base portion 2a and the top portion 2b and to allow reducing or removing the housing space <NUM> defining a compact configuration of the underwater docking station.

<FIG> is a lateral view clearly showing the housing space <NUM> in the extended configuration of the underwater docking station, in which the top portion 2a is far from the base portion 2b. In <FIG>, an underwater device <NUM>, such as an AUV, is ready to couple to the docking station by entering into the housing space <NUM>.

Further, the support plate <NUM> shows a guide <NUM> in the form of a vertical bar starting from the housing space entrance and heading backwards towards the back of the station; the guide <NUM> is designed for guiding the underwater device <NUM> when received by the underwater docking station <NUM> in the housing space <NUM> (e.g., avoids that the underwater device <NUM> hits the scissor mechanism <NUM> and promotes a correct relative positioning of the underwater device <NUM> with respect to the docking station, for example for recharging purposes and/or for data exchange as below described in more detail). Obviously, the underwater device <NUM> has a corresponding seat that receives the emerging guide <NUM>. It is clear that, in an alternative construction, the support plate <NUM> may include a seat and the underwater device <NUM> have the emerging guide.

In addition, the support plate <NUM> shows a locking mechanism 15a, such as one or more projections emerging from the plate <NUM>, for allowing the underwater device <NUM> to lock to the underwater docking station <NUM>, for example by means of corresponding clamps.

Notably, the support plate <NUM> may be substituted with a different plate having guide <NUM> and/or locking mechanism 15a dedicated to a different types/positions of corresponding seat and/or clamps of another underwater device <NUM>.

Going back to the scissor mechanism <NUM> between the top portion and the base portion, the compact configuration is shown in the lateral view of <FIG>. In this situation, the base portion and the top portion are substantially into contact and no space is defined between them (i.e., no underwater device <NUM> may be housed between the two portions in the docking station). <FIG> shows a transport configuration that reduces the overall dimension of the docking station during transportation and/or installation and positioning on the seabed.

In order to automatically switch between the configuration of <FIG> and <FIG>, the underwater docking station further comprises a reversible actuator active on the mechanism <NUM> to increase or reduce the housing space <NUM> by approaching or distancing the base portion 2a and the top portion 2b. In more detail, the mechanism <NUM> comprises at least two scissor mechanisms, both partially visible in <FIG>, that are placed at opposite lateral side with respect to the housing space <NUM>. Each scissor mechanism respectively includes a first bar and a second bar hinged to each other at a respective intermediate point. The first bar has a fixed portion hinged to the base portion 2a and a movable portion slidable along the top portion 2b. The top portion 2b includes a guide <NUM>, in the form of an endless screw and the movable portion of the first bar may slide over the guide <NUM>. In this regard, the reversible actuator comprises a motor and the endless screw <NUM>; the motor rotates the endless screw in one direction or in the opposite direction to achieve increasing or reducing the housing space <NUM>. Indeed, the endless screw is rotatably coupled to the top portion 2a and a threaded head <NUM> fixed to the movable portion of the first bar of the mechanism <NUM> is coupled to and moving over the endless screw. When the screw is rotated clockwise, the threaded head <NUM> is dragged in one direction; when the screw is rotated counter clockwise, the threaded head <NUM> is dragged in the opposite direction.

Differently, the second bar has a fixed portion hinged to the top portion 2b and a movable portion slidable along the base portion 2a. The base portion 2a includes a sliding seat <NUM> and a pin of the movable portion of the second bar slides within the sliding seat <NUM> during movement between the open and the closed positions.

By properly actuating the motor and synchronizing the two scissor mechanism <NUM>, it is possible to configure the underwater docking station between the configuration of <FIG> and of <FIG> (or to achieve any intermediate conditions). When the endless screw is blocked, the scissor mechanism <NUM> is blocked too and the achieved configuration of the docking station is stable.

The top portion 2a of the support structure is substantially flat and designed to receive in support another underwater device <NUM>, for example a ROV (see <FIG>). Also the top panel of the portion 2a may include lightening holes (e.g. rectangular) to reduce weight and to provide undercuts for the ROV coupling and/or clamping (if necessary). Further, the top portion 2a defines a frame that houses a number of electric and electronic components for the working and communication of the docking station.

The top portion 2a usually houses a battery associated to the support structure <NUM> to provide electric power to various components here after described such as a control unit <NUM>, an optical communication module <NUM>, an acoustic communication module (hydrophones <NUM>), a camera <NUM>, LEDs <NUM> and the respective actuators. The battery of the underwater docking station is rechargeable, e.g., wirelessly, through the one or more underwater devices <NUM> that provides electric power. Indeed, the ROV shown in <FIG> may be electrically powered by the umbilical cable (e.g., from a surface vehicle) and thereby may wirelessly provide electric power to recharge the battery of the docking station without having to recover the same form the bed floor.

Notably, the support structure <NUM> further houses a wireless recharge module configured to couple to a corresponding wireless recharge module of the underwater device <NUM> to charge a battery of the underwater device <NUM>. In this regard, electric power recharge is in the reverse direction, namely towards the underwater device <NUM>, which in this case may be an AUV that has no power connection to the surface vehicle. The wireless recharge module is configured to recharge the battery of the underwater device <NUM> if the corresponding wireless recharge module of the underwater device is at a distance from the wireless recharge module of less than <NUM>,<NUM>, in particular when the underwater device <NUM> is correctly positioned in the housing space <NUM> of the support structure <NUM>. The recharge module of the underwater device <NUM> could be used both to receive electric power from e.g., a ROV, and to provide electric power to e.g., an AUV as mentioned.

As visible from <FIG> and <FIG>, the docking station <NUM> further comprises one or more lights, such as LEDs <NUM>, associated to the support structure <NUM> in correspondence of the front panel of the top portion 2a to allow illuminating the surroundings of the underwater docking station <NUM>. Two LEDs are shown on opposite sides of the front panel to provide (uniform) light to the front of the station in dark subsea environment. A control unit <NUM> drives the lights/LEDs and is also used to fully control the docking station working.

The top portion 2a also houses a camera <NUM> placed in correspondence of the front panel. The camera <NUM> is connected to the control unit <NUM> and allows viewing and/or filming of images surrounding the underwater docking station; the camera has a certain field of view and the collected data may be stored in a memory connected to the control unit <NUM>. As visible in <FIG>, a camera actuator <NUM> (e.g., a stepper motor) is active on the camera <NUM> upon control unit command to move the axis of the field of view between different operative positions, wherein the axis of the field of view of the camera <NUM> is directed along different directions. In other terms, the camera <NUM> is not fixed to the support structure but may be moved to look at different areas, specifically to the environment in front of the docking station. For example, images may be used to command the underwater device <NUM> during working or during approach to the docking station for recharge or data exchange. The camera <NUM> is configured to at least rotate along a rotation axis <NUM> that is transversal, and in particular orthogonal, to the axis of the field of view of the camera <NUM>. The rotation axis <NUM> is substantially horizontal in use conditions of the underwater docking station <NUM> so that the field of view can be moved from framing the seabed towards the surface by pure rotation around the horizontal axis <NUM>. In other terms, the control unit <NUM> is configured to command the camera actuator <NUM> exclusively to rotate the camera <NUM> and move the axis of the field of view of the camera <NUM> along a vertical plane in use condition of the underwater docking station <NUM>; for example, the control unit <NUM> may be configured to rotate over a rotation angle range of at least <NUM>° and in particular of at least <NUM>°.

As it is visible from <FIG>, the underwater docking station <NUM> further comprises an optical communication module <NUM> configured for data communication with one or more underwater devices <NUM> along an optical communication axis <NUM>. Indeed, the optical communication module <NUM> is configured to communicate on a line of sight along the communication axis <NUM> with another optical communication module <NUM> of the underwater device <NUM> with its respective communication axis aligned on the line of sight.

The optical communication module <NUM> comprises a wireless optical modem that in the specific embodiment has a maximum communication range of about <NUM>. Of course, maximum distance is affected by water turbidity and environment noise. The optical communication module <NUM> has a data rate of at least 5Mbit/sec, in particular of at least <NUM>/10Mbit/sec and is configured for working at least up to a depth of <NUM>. The optical communication module <NUM> is a bi-directional transceiver and is configured for achieving video data transfer, for example for <NUM> video data transfer.

In general terms, the optical communication module <NUM> is used for transmitting and receiving data at high data rate with good bandwidth using optical signals. For the purposes of the present disclosure, with "optical signal" shall be intended a signal within the range of visible light - about in the [<NUM> - <NUM>] nm range - and/or in the range of the infrared light - about in the [<NUM> - <NUM>] nm range - and/or in the range of the ultraviolet light - about in the range [<NUM> - <NUM>] nm range. The clause "and/or" is provided since in an embodiment the bandwidth of the optical signal may be so broad to cover at least two or three among the ranges of the visible light, the infrared light, the ultraviolet light.

A coupling arrangement <NUM> is used to mount the optical communication module <NUM> to the support structure <NUM> in order to allow a relative movement between the optical communication module <NUM> and the support structure. The movement is used to properly orient the communication axis <NUM> and therefore the line of sight of the optical module. An actuator <NUM> is shown in <FIG> and is active on the optical communication module <NUM> to move the optical communication axis <NUM> between (at least) one first operative position and one second operative position, wherein, in the first operative position, the communication axis <NUM> is directed along a first communication direction <NUM> and, in the second operative position, the communication axis <NUM> is directed along a second communication direction <NUM> that is different from the first communication direction <NUM>. The exemplificative directions are shown in <FIG> and <FIG>. The possibility to move the communication axis is used to allow an easier and more reliable communication between the docking station and the underwater devices <NUM> according to the position of the specific underwater device <NUM> with which communication is desired.

As mentioned, an AUV may be housed in the housing space <NUM> below the top portion 2a (see <FIG>). When the AUV is in place below the top portion, the communication axis <NUM> of the optical communication module <NUM> is rotated downwards from the position shown in <FIG> so to reach the second communication direction <NUM>. Correspondingly, the optical module <NUM> (which may be of the same type as above described) included in the AUV is rotated upwards so that the two modules are in sight and may exchange data.

Differently, when a ROV is positioned on top of the support structure <NUM> as shown in <FIG>, the communication axis <NUM> of the optical communication module <NUM> is rotated upwards from the position shown in <FIG> so to reach the first communication direction <NUM>. If necessary, a corresponding optical communication module (which may be of the same type as above described) included in the ROV is moved to be in line of sight with module <NUM> and data are exchanged. Given the fact that more than one underwater device <NUM> may couple with the docking station in different positions, the optical module mobility allows proper communication with all of the same devices <NUM> simply changing the communication axis. In this regard, the first communication direction <NUM> and the second communication direction <NUM> are directed vertically in use condition of the underwater docking station <NUM>; in the example the first communication direction <NUM> is directed upwards and the second communication direction <NUM> is directed downwards.

The control unit <NUM> is connected to the optical communication module <NUM> to manage the communication with said one or more underwater devices <NUM>, and to the actuator <NUM> to drive the optical communication axis <NUM> (by moving the optical communication module <NUM> or a portion thereof) to the first operative position or to the second operative position. The optical communication module <NUM> rotates along a rotation axis <NUM> that is transversal, in particular orthogonal, to the communication axis <NUM>. As visible form the figures, the rotation axis <NUM> is substantially horizontal in use conditions of the underwater docking station <NUM>, and therefore the actuator <NUM> is configured to (exclusively) rotate the optical communication module <NUM> to move the optical communication axis <NUM> between the first operative position and the second operative position so that any communication directions lie in a vertical plane. In particular, the control unit <NUM> is configured to rotate over a rotation angle range of at least <NUM>° and more in detail of at least <NUM>°.

Clearly, the optical communication axis <NUM> is movable to a plurality of additional positions in addition to the first operative position and the second operative position, and the optical communication module <NUM> is configured to communicate along additional communication directions in one or more of said additional positions. For example, in the configuration of <FIG>, the communication axis <NUM> is horizontal and any underwater device <NUM> placed in front of (and in line of sight with) the docking station may communicate in the shown position of the module <NUM>.

Further, to the above optical communication system, the docking station is further provided with an acoustic communication module. Since the optical module <NUM> allows for good data transfer rate, but requires line of sight and proximity, the applicant has implemented a second communication module that uses acoustic and/or ultrasound signals. This system may communicate at greater distances than the optical system and does not require line of sight. However, the data transfer is much reduced. Therefore, the acoustic module is mainly used for exchanging commands, while the optical for important and large data transfer (e.g., video files). The combination of an optical communication and of a ultrasonic and/or acoustic communication between the base station <NUM> and the underwater device <NUM> allows to exchange high-bandwidth data using the optical signal and to obtain long communication distances, even if at a lower bandwidth, using the ultrasonic and/or acoustic signal, in particular without requesting complex and/or delicate transmitters differing from a differently configured or adapted hydrophone. The ultrasonic and/or acoustic communication and the optical communication constitute two distinct logic channels for allowing a communication between the base station and underwater device <NUM>. The fact that the operative connection of the base station <NUM> with the underwater device <NUM> takes place through two logic channels of communication operating at frequencies significantly different each other allows to guarantee that some noise sources that may affect one logic channel do not interfere with the other logic channel; in some embodiments those two logic channels may be used simultaneously for redundancy - especially for redundancy of control - thereby achieving an increase of reliability of communication.

For the purposes of the present disclosure, with "ultrasonic signal" shall be intended a signal whose frequency is higher than <NUM>, preferably comprised in the interval [<NUM> - <NUM>] kHz.

For the purposes of the present disclosure, with "acoustic signal" shall be intended a signal whose frequency is equal or lower than <NUM>, preferably comprised in the interval [<NUM>,<NUM> - <NUM>] kHz, more preferably in the interval [<NUM>,<NUM> - <NUM>] kHz.

It is noted that the ultrasonic and/or acoustic signal is so defined since in an embodiment its bandwidth may be located between the frequency range of the ultrasonic signals and the frequency range of the acoustic signals, or the plurality of carriers of the channels of the signal may be located between the frequency range of the ultrasonic signals and the frequency range of the acoustic signals.

The Applicant actually notices that according to IEEE Communications Magazine, January <NUM> "Underwater Acoustic Communication Channels: Propagation Models and Statistical Characterization", by Milica Stojanovic, Northeastern University, and James Preisig, Woods Hole Oceanographic Institution, the power spectral density of the ambient noise in an underwater environment, at least due to the wind and shipping activity has a minimum substantially located between <NUM> and <NUM>, more in particular between <NUM> and <NUM>. Thus, in a preferred, non-limiting, embodiment, the frequency range for the ultrasonic and/or acoustic signal may be located in the [<NUM> - <NUM>] kHz range, preferably in the [<NUM> -<NUM>] kHz range.

In this regard, the underwater docking station comprises one or more hydrophones <NUM> associated to the top portion 2a of the support structure <NUM> and configured to allow a transmission and reception of ultrasonic and/or acoustic signals. The control unit <NUM> is connected to the hydrophones <NUM> to manage communication with ultrasonic and/or acoustic signals. Since the transmission of the ultrasonic and/or acoustic signals is a substantially non-directive transmission, the control unit <NUM> transmits using the hydrophone <NUM> when the underwater docking station <NUM> and the underwater vehicle <NUM> are at more than a first distance D1 (e.g., between <NUM> and <NUM> or more). Since the transmission of optical signals through the optical communication module <NUM> is a substantially directive transmission, the control unit <NUM> transmits with the optical communication module <NUM> when the underwater docking station <NUM> and the underwater device <NUM> are at a second distance D2 (e.g., between <NUM> and <NUM>). Notably, the first distance D1 is greater than the second distance D2.

In order to properly work, the control unit <NUM> is configured to receive or determine a distance between the underwater docking station <NUM> and the underwater device <NUM>, and select a communication using either the hydrophone <NUM> or the optical communication module <NUM> based on said calculated or received distance.

Albeit this shall not be considered limiting, in an embodiment the body of the hydrophone <NUM> is substantially elongated, and defines a main direction of extension that defines substantially a pointing direction or axis of the hydrophone. The hydrophone <NUM> is specifically configured to operate in a full-duplex communication environment, i.e. wherein simultaneous reception and transmission takes place.

The invention is not limited to the annexed figures. For such reason, the reference numbers provided in the annexed claims are provided for the sole purpose of increasing the intelligibility of the claim, and shall not be construed as limiting.

Claim 1:
An underwater docking station (<NUM>) for communication with one or more underwater devices (<NUM>), the underwater docking station comprising:
- a support structure (<NUM>) comprising a base portion (2a), a top portion (2b) and in particular a mechanism (<NUM>) interposed between the base portion (2a) and the top portion (2b) to allow moving the base portion (2a) away from the top portion (2b) defining an housing space (<NUM>) for receiving the underwater device (<NUM>) between the base portion (2a) and the top portion (2b) and to allow reducing or removing the housing space (<NUM>) defining a compact configuration of the underwater docking station;
- an optical communication module (<NUM>) configured for communication with said one or more underwater devices (<NUM>) along an optical communication axis (<NUM>);
- a coupling arrangement (<NUM>) mounting the optical communication module (<NUM>) to the support structure (<NUM>);
- an actuator (<NUM>) active on the optical communication module (<NUM>) to move the optical communication axis (<NUM>) between at least one first operative position and one second operative position, wherein, in the first operative position, the communication axis (<NUM>) is directed along a first communication direction (<NUM>) and, in the second operative position, the communication axis (<NUM>) is directed along a second communication direction (<NUM>) different from the first communication direction (<NUM>);
- a control unit (<NUM>) connected to:
∘ the optical communication module (<NUM>) to manage a communication with said one or more underwater devices (<NUM>), and
∘ the actuator (<NUM>) to drive the optical communication axis (<NUM>) to the first operative position and to the second operative position.