Underwater network having buoyancy compensation and anchoring systems

An underwater wireless network can include plurality of nodes, each node having a cylindrical housing, a repeater, a transducer and a buoy. The housing defines a void and encloses the repeater. The transducer can be tethered to the housing and a buoy can be tethered to said transducer. Each node also includes at least two hemi-cylindrical flukes that can be pivotably attached to the housing. The housing can further be formed with at least two flood ports, and corresponding plugs are inserted into a respective fill port. Lanyards interconnect each flukes with a respective plug. During transport, the flukes can surround the transducer and the void is empty, which renders the node neutrally buoyant for ease of transport. For deployment, the flukes are pivoted away from each other to tighten the lanyards, which pull the plugs out of the flood ports, to further flood the void and deploy the node.

FIELD OF THE INVENTION

The present invention pertains generally to systems and methods for providing an underwater wireless data network. More specifically, the present invention pertains to systems that provide for neutral buoyancy of underwater network nodes for easy movement during underwater transport, while also providing for ballast, anchoring and anti-roll effects after deployment of the nodes.

BACKGROUND OF THE INVENTION

It is sometimes desired to provide a capability to extend wireless networking capabilities from the terrestrial to the underwater domain, using through-water acoustic communications. To do this, a number of modem repeater nodes in a fixed network and associated equipment can make up an undersea communication grid. This provides an undersea network capable of providing connectivity between underwater fixed sensor grids, as well as between underwater networks and above water mobile platforms and command centers for various types of systems, platforms, missions, and sensor networks.

There can often be inherent difficulties in establishing underwater networks. The first difficulty can be transporting each network node to its desired underwater location. It may often more convenient to transport the nodes underwater. In this case, it can be further desired to maneuver the nodes to a precise location manually with a diver. If the nodes are negatively buoyant, this can result in a diver attempting to manually maneuver a node that might weigh over a hundred pounds, which is obviously an undesirable situation that should be avoided if at all possible.

Once nodes have been positioned according to the user's needs, it can be desired to anchor the nodes so that they remain in position with respect to other nodes for optimum communications, (such as data transfer, by way of non-limiting example) according to the prevailing undersea conditions (water temperature, existence of thermoclines, etc.). But underwater forces such as current can move the nodes to an undesired location without the knowledge of the network operator. This can cause decreased network performance, and in extreme cases, the movement of the nodes can make the network inoperable.

In view of the above, it is an object of the present invention to provide an underwater network with nodes that are neutrally buoyant during underwater transport. It is another object of the present invention to provide an underwater network with nodes that can be transported by a single diver, with or without the aid of an underwater transport system such as a Seal Delivery Vehicle (SDV). Another object of the present invention to provide an underwater network with nodes that have a low hydrodynamic drag to facilitate delivery underwater. Yet another object of the present invention is to provide an underwater network with nodes that allow for ballasting to create negative buoyancy for the node once it is desired to deploy the node to fix the node in position on the ocean or harbor floor. Still another object of the present invention is to provide an underwater network with nodes that provide anchoring and anti-roll effects that self-orient the nodes with respect to the sea/harbor bottom once deployed. More generally, another object of the present invention is to provide a method for delivery of a payload underwater that uses a neutrally buoyant housing, which can be flooded to deploy the payload according the needs of the user.

SUMMARY OF THE INVENTION

An underwater wireless network according to several embodiments of the invention can include several underwater nodes. Each node can include a housing, a repeater, a transducer and a buoy. The housing defines a void, which can contain the repeater. The transducer can be tethered to the repeater and a buoy can be tethered to said transducer. Each node can further include at least two hemi-cylindrical flukes that can be pivotably attached to the housing at one end. The flukes can be selectively pivoted to deploy the transducer and the buoy.

The housing can further be formed with at least two flood ports, and the nodes according to several embodiments can further include at least two plugs, with each plug corresponding to a respective fill port. A lanyard or lanyards can interconnect the flukes and the plugs. During transport, the flukes surround the transducer and the buoy so that the node can be more hydrodynamic when the node is transported underwater, and the plugs are inserted into the housing render the void watertight and to make the node neutrally buoyant. This transport configuration facilitates the transport of the node to a desired location for subsequent deployment.

For deployment, the flukes are pivoted away from each other, which tighten the lanyards and pull the plugs out of the flood ports. Once the plugs are pulled, a path of fluid communication can be established into the void, the void floods with water and the node becomes negatively buoyant. The buoy rises as far its tether will permit, which further suspends the transducer underwater for further use. Once this occurs, the node is in a deployed configuration and ready for incorporation within the wireless network.

In several embodiments, each node can further include a spring or resilient member that biases the flukes towards the deployment configuration, and a releasing means for engaging the resilient member. In other embodiments, the plugs can be coated with a corrosive material, with the corrosive material and plug material being chosen so that the corrosion of the plugs to the point where they fall out of the flood ports to flood the void occurs at a predetermined interval. In other embodiments, each node can further include a plurality of small explosive charges that correspond to a respective plug. The charges are placed on the node so that selective activation of the charges forces the plugs out of the flood ports, to flood the void and deploy the node.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Referring now to the Figures, the underwater wireless data transfer network according to several embodiments of the present invention can be shown and can be generally designated by reference character10. In brief overview, and as shown inFIG. 1, the system10includes a plurality of underwater network nodes12that can be positioned and anchored on the floor18of an ocean or harbor. The nodes12can communicate with each other, with underwater assets such as submarine46and with surface assets14. The network10can also be placed in communication with airborne assets16to establish an expanded communications network. But to do this, the underwater nodes must be efficiently and effectively maneuvered into position on the floor18of the ocean/harbor. The structure of the nodes12, and the manner in which the nodes12can be maneuvered into position and fixed in place within the network10during deployment, are described in more detail below.

Referring now toFIGS. 2-5, the aforementioned node12can be shown in more detail. As shown, each node includes a housing20that defines a void22. At least two hemi-spherical flukes24are pivotably attached to a housing cap50, which can be further attached to one end of the housing. A fairlead30can be attached to the housing cap50, so that the fairlead30is concentric to the flukes24. A repeater28can be inserted into housing20, and a transducer26can be electrically connected to repeater28via an electrical tether31that can be run through fairlead30(SeeFIG. 7). A buoy32can be further tethered to transducer26via tether29(FIG. 7). At the opposite end of the housing20from the flukes, a spacer36can position repeater28within the housing, and the spacer and repeater28can be retained in place with an end cap38that can be fastened to the housing20.

The nodes12for the network10according to several embodiments of the present have a transport configuration and deployment configuration. For the transport configuration, it is desired that the nodes12have a neutrally buoyant configuration, and also that the nodes12have a minimum profile so that they are as hydrodynamic as possible, so that the user may transport the nodes12underwater, if desired. To do this, and as shown inFIGS. 3 and 4, the flukes24are positioned in the transport configuration so that they enclose the fairlead30and the transducer26, and the electrical tether31can be coiled within fairlead30. Tether29and buoy32are enclosed within flukes24, as shown in theFIGS. 3 and 4. When node12is in a transport configuration, the flukes24can be fixed in place by aligning end cap holes46with fluke holes54and inserting a pull pin52(seeFIG. 6).

As mentioned above, the housing20can be formed with void22. The housing20, end cap38and housing cap50cooperate to make the void22watertight. With this configuration, the node12has a cylindrical, tubular overall profile for ease of transport, and the buoy32and void22cooperate to provide a neutrally buoyant effect for the node, to facilitate transport. The materials for the node and the volume of the void (i.e., the dimensions of housing20) can be chosen so that the node is neutrally buoyancy when the node is configured in this manner.

Referring now toFIGS. 4-6, the structure of the node12that facilitates deployment can be shown in greater detail. As shown inFIGS. 4 and 6, housing cap50can be formed with at least two flood ports40, and a corresponding plug42can be inserted into each fill port. For each plug42, a lanyard44can be attached to plug42and to fluke24to interconnect plug42with fluke24. The lanyard44can be attached in any manner that is known in the art, such as by a weld or by a fastener such as a screw or rivet (not shown). The point of attachment of the lanyard44to the fluke24and the length of lanyard44are chosen so that lanyards pull the plugs42are pulled out of their respective flood ports40when the flukes24are deployed, as described below.

A detent48is mounted on end cap50, and a hinge block56can be fixed to the interior concave surface of fluke24, as shown inFIG. 6. To pivotably attach the flukes to housing cap50, a hinge bar54can be used. To do this, holes can be formed in detent48and in both ends hinge block56(the holes are not shown inFIG. 6). The holes in one end of hinge bar54are then aligned with the holes in detent48, and a retaining pin52acan be inserted therethrough. Similarly, the holes in the other end of the hinge bar54can be aligned with the holes in hinge block56and retaining pin52bcan be inserted therethrough to pivotably attach fluke24to housing cap50.

Once in position within network10, the nodes are ready for deployment. For deployment, the end cap34can be removed. Next, flukes24are pivoted away from each other, and from the enclosed fairlead30, transducer26and buoy32. It should be appreciated that the flukes can be biased toward a deployment configuration to facilitate this movement away from each other by using a spring (not shown) or other type of resilient member. As the flukes pivot away from each other, the plugs are pulled out of respective flood ports40. Once this occurs, a path of fluid communication can be established into the void22, and the void22becomes flooded. As void22floods, the node12becomes negatively buoyant and sinks in place to the floor18of the ocean or harbor.

Referring now toFIG. 7, the fully deployed configuration for communications node12is shown. As shown, node12sinks to the floor because it is negatively buoyant and the flukes24provide an anchoring effect by digging into the ocean/harbor floor. The hemi-cylindrical geometry of the flukes24allows the flukes to dig into the ocean floor, which further provides an anti-roll effect for the node12. Additionally, buoy32(which at a component level remains positively buoyant) floats toward the surface once it is freed from its transport position within the flukes. As buoy32rises, the tethered transducer26also rises. The buoy32continues to rise until it reaches the end of the tether29and electrical tether31. The rising motion deploys the transducer26into an optimum position for more efficient data transfer within the network10. The deployed configuration for the node12can be shown inFIG. 7. For the deployed configuration, void22has flooded and node is negatively buoyant. At the same time, transducer can be tethered to housing20via electrical tether29, and buoy32can be tethered to transducer to keep transducer26positioned above housing20.

In addition to the embodiments described above, it should be appreciated that there are other means to selectively remove the plugs42from the flood ports40for deployment of the node12. For example, explosive micro-charges (not shown) could be placed on the plugs42to force plugs42out of the flood ports40when desired by the operator. Alternatively, it may be desired to coat the plugs42with a corrosive material prior to placement into the flood ports40. The nodes12may then be moved into place, and the plugs can corrode due to effects of the corrosive material until the plugs either fall out of the fill port or until water pressure urges the plug42out of the fill port40.

In addition to the underwater data transfer network10described herein, it should be appreciated that in a more general sense, the nodes12can be configured so that a payload can be inserted into the housing so that the node is neutrally buoyant and has a small hydrodynamic profile. Then, once the nodes are in position, the flukes can be deployed as described above to make the node negatively buoyant, and further to deploy the payload on the floor18of the ocean or harbor.