Patent Application
20250019039
This present disclosure relates to a hull for deployment as an underwater habitable vessels, in particular, a hull made up of a series of connected modules
Various types of underwater habitable vessels are known including submarines, submersibles and underwater habitats. Submarines and submersibles are structures that are both able to propel themselves underwater and enable humans to live below the water's surface for extended periods of time, for example, several hours, weeks, or even months. Underwater habitats are structures that enable humans to live below the water's surface for extended periods of time, for example, several hours, weeks, or even months. Unlike submarines and submersibles, underwater habitats are not typically able to propel themselves and are instead deployed to a stationary location on the sea floor by a support vessel or shore-based crane. The enclosed interior volume of an underwater habitable vessel supports a breathable atmosphere so that humans can work, rest, eat, and/or sleep in the habitat during the course of a mission.
Previously deployed underwater habitats, such as SEALAB I, II, and II, Tektite I and II, Helgoland, and the Aquarius Reef Base, were each developed with a specific mission in mind and, as such, are not designed to be taken apart and rebuilt into a different configuration more suitable for a new mission with different operational requirements.
More recently, Jiangsu University of Science and Technology in US2023/080177A1 have proposed a pressure-resistant hull for a submersible including a plurality of unit hulls sequentially strung together in a spiral to facilitate the organic adjustment of the number of the unit hulls. However, the spiral arrangement is hard to assemble and support securely underwater, since each unit hull is at a different height. In addition, the location of the apertures in the unit hulls means that only one type of arrangement is possible (a spiral) is possible which may not be ergonomically suitable for all mission types and reduces the number of ways in which the hull can be configured. A further drawback of the spiral arrangement is that its geometry means that each hull unit can only be relatively small and so there is no possibility for a single, relatively large internal space that can house a large, bulky piece of equipment, which may limit the capabilities the submersible can be provided with.
The invention is defined by the independent claims, with further embodiments defined by the dependent claims.
A first aspect of the invention relates to a hull for deployment as an underwater habitable vessel. The hull comprises at least two hull wall modules connected in series to enclose an interior volume of the underwater habitable vessel. The interior volume is bounded by the hull wall modules. Advantageously, a modular hull provides an underwater habitable vessel that can easily be configured with the optimum number of hull wall modules for a given mission. In particular, it can be reconfigured, for example, with different arrangements or numbers of hull wall modules, such that it can be repurposed and redeployed for a variety of different mission types in a range of underwater environments and locations.
In some embodiments the hull wall modules may be connected together via mating rings, one positioned between each hull wall module. Each mating ring may comprise two axial faces, one on each side of the mating ring, each configured to mate with a corresponding axial face of an adjacent hull wall module. Each mating ring may further comprise two circumferential grooves, one in each of the axial faces of the mating ring, each configured to receive a seal, wherein the seal is configured to provide a watertight connection between the mating ring and the adjacent hull wall module. Advantageously, providing the seal grooves in a mating ring means that they do not need to be included in the hull wall modules themselves. As a result, each axial face of each hull wall module can be identical, since there is now no need to include a seal groove in one, but not the other, axial faces of abutting hull wall modules. This simplifies the manufacturing of the hull wall modules without significantly increasing the complexity of the assembly process.
In some embodiments a portion of each mating ring may extend beyond an outer surface of the hull wall modules and comprise at least one attachment point for mounting an object outside the hull. The at least one attachment point may comprise a bolt hole or rail The portions of the mating rings extending beyond the outer surface of the hull beneficially provide attachment points for other objects and equipment to be securely attached to the outside of the hull without having to manufacture a 3D attachment structure in the otherwise smooth surface of the hull wall module itself, which can be complicated to cast or create via an additive manufacturing method.
In some embodiments the hull wall modules may be made of metal. At least one of the mating ring and the flanges may further comprise an insulating layer configured to electrically isolate the hull wall modules from each other. This helps reduce corrosion.
In some embodiments each mating ring may comprise a plurality of through-holes, arranged about a circumference of the mating ring. Each mating ring may be configured to be aligned with corresponding through-holes arranged in flanges of a pair of adjacent hull wall modules to thereby define triplets of aligned through-holes. Each aligned triplet of through-holes may configured to receive a bolt to thereby connect the pair of hull wall modules together. The hull wall modules may be detachably connected to each other. This provides a secure, yet temporary, way of connecting the hull wall modules together and avoids the need for welding.
In some embodiments there are at least three hull wall modules. The hull wall module at a first end of the series of the at least three hull wall modules and the hull wall module at a second, opposite end of the series of the at least three hull wall modules may be configured as end-caps comprising identical first form factors. The at least one remaining hull wall module may be configured as an intermediate module. Each at least one remaining hull wall module may comprise a second identical form factor different to the first form factor. Advantageously, providing each hull module in one of two form factors (i.e., shape) reduces manufacturing complexity, since tooling or processes only need to be designed for two types of module (rather than needing to be entirely redesigned if a modular structure were not used), whilst increasing the range of possible configurations for the habitat compared to the range possible with a single type of hull module.
In some embodiments the first form factor may comprise an open-sided hemisphere or torisphere, and wherein the second form factor comprises a cylinder. These shapes provide a naturally strong structure for withstanding external and internal pressures due to their basic geometry. Moreover, a combination of hemispheres/torisphere and cylinders enables a single, large interior volume to be provided within the habitat thereby allowing large, bulky equipment to be installed.
In some embodiments at least one or each hull wall module comprises one or more apertures in a surface thereof. The apertures may each comprise an aperture fitting configured to be fitted with interchangeable components. The interchangeable components comprise: windows, blanks, hatches, moonpools, moonpool hoods, penetrator plates, (wherein each penetrator plate may comprise one or more through holes for penetrators) penetrators, or a connecting structure configured to connect to an aperture of a second hull and to allow passage of a human therebetween. The aperture fittings may be configured to form a watertight connection with the interchangeable components when fitted. Configuring the apertures such that they are able to receive a variety of different components means that the hull can easily be reconfigured for a different mission by swapping out one type of component for another. A damaged or worn component can also be replaced without having to replace an entire hull wall module. This interchangeability also simplifies the manufacturing process since each aperture can have the same design. Moreover, providing multiple apertures in each hull wall module enables multiple hulls to be connected together via connecting structures fitted to apertures in each hull, thereby enabling a plurality of habitats to be deployed together, increasing the range of configurations available for different mission types.
In some embodiments the at least one intermediate module may comprise three or more apertures, wherein the apertures are regularly spaced around the circumference of the intermediate module. Such an arrangement evenly distributes pressure loads applied on the apertures around the hull wall module thereby avoiding asymmetric pressure loads on the hull.
In some embodiments the hull wall modules may be connected along a longitudinal axis passing through the interior volume. Arranging the hull wall modules and the interior volume they create along a single axis provides a structure that is both easy to support securely on the seafloor and capable of receiving larger equipment than a hull of equivalent volume constructed along a non-linear axis. Furthermore, assembling a hull with modules arranged along a single axis is comparatively easy to perform on shore or the deck of a ship compared to a hull with a non-linear arrangement of modules.
In some embodiments there may be a stabilising platform configured to support the hull on the seafloor such that the longitudinal axis is held in a horizontal or vertical orientation. Advantageously, the stabilising structure enables the habitat to be held in a level orientation (whether horizontal or vertical) which is more comfortable for its occupants, even on an uneven seafloor. Moreover, providing a habitat that can be supported in two orientations increases the range of ways it can be configured, depending on the mission, and, in a system of multiple habitats, enables the living space to be extended vertically, which may be desirable on laterally constricted underwater sites.
In some embodiments the internal diameter of each hull wall module is in the range of: 2-12 m, 3-8 m, or 4-6 m. A pressure hull of such large size provides a large interior space for the installation of large amounts of bulky equipment. This enables the endurance of and range of capabilities of an underwater mission to be increased.
In some embodiments the hull wall modules may be manufactured by an additive manufacturing technique. Hull modules manufactured by an additive manufacturing technical have improved structural properties compared to hulls manufactured by traditional forging techniques. In particular, the improved uniformity of the hull wall created by additive manufacturing has fewer weak points and is less likely to fail at great risk to any human occupants.
In some embodiments there is provided a system of underwater habitats comprising two or more of the hulls coupled together via one or more connecting structures configured to allow passage of a human therebetween. Advantageously, the modular concept allows a range of hulls to be assembled and interconnected using the same small range of underlying building blocks to create a large variety of possible configurations of interconnected habitats. This increases the overall reconfigurability of the overall system and range of mission types it can be used for.
A second aspect of the invention relates to a kit of parts for a hull of an underwater habitable vessel. The kit comprises at least two hull wall modules connected in series to enclose an interior volume of the underwater habitable vessel. The interior volume is bounded by the hull wall modules. Advantageously, a modular hull provides an underwater habitable vessel that can easily be configured with the optimum number of hull wall modules for a given mission. In particular, it can be reconfigured, for example, with different arrangements or numbers of hull wall modules, such that it can be repurposed and redeployed for a variety of different mission types in a range of underwater environments and locations. A third aspect of the invention relates to a hull wall for an underwater habitable vessel. The hull wall comprises: a plurality of aperture fittings protruding outwardly from the hull wall and defining apertures therethrough; and a plurality of hull stiffeners, at least one arranged between each pair of adjacent aperture fittings and configured to resist bending forces applied to the hull wall by the aperture fittings. Advantageously, strengthening the hull in this way enables the apertures to be made larger and the hull wall thinner due to the extra support provided.
Embodiments of the invention are described below, by way of example, with reference to the following drawings, in which:
The following detailed disclosure outlines the features of one specific embodiment of the present invention. In addition, some (but by no means all) variants of one embodiment that might be implemented whilst still falling under the scope of the present invention are also described. The claimed invention relates to a hull for deployment as an underwater habitable vessel. The description below refers to the components of the hull in both their assembled and disassembled states. It is to be understood that the hull can be provided: in its assembled state; as a kit of parts for assembly into a complete, or partially complete, hull; or in a partially assembled state. Therefore, where two components are said to be attached, it is to be understood that those components may also be provided as part of the kit of parts in a disassembled state but are configured to be attached to each other. Likewise, where to components are said to be configured to be attached to each other, they may be provided in an assembled configuration where they are attached to each other.
Where the underwater habitable vessel is a submarine or submersible, it is capable of self-propelled travelling. Where the habitable vessel is an underwater habitat, unlike a submarine or a submersible, but in common with other underwater habitats, the hull 1 is not self-propelled. Instead, the hull 1 is deployed to the seafloor by a surface vessel or shore-based crane. Alternatively, the hull 1 can be deployed using an underwater vehicle rather than a surface mounted crane. Once deployed to depth, the interior volume 2 of the habitat is not in atmospheric communication with the surface. Although the terminology “seafloor” is used herein, it is understood that this refers to the bed of a sea, river, lake, estuary, or any other body of water.
When connected together, the hull wall modules 10, 20 define a pressure hull able to withstand both internal and external pressures. For example, the pressure hull can withstand an external pressure of at least 5 atm such that it can be deployed to a depth of 50 MSW or at least 20 atm such that it can be deployed to a depth of 200 MSW. In one realisation of the habitat, this is achieved by hull wall modules manufactured from 40-80 mm thick steel, preferably 60 mm thick. The interior volume is maintained at surface pressure or a pressure above atmospheric pressure, for example, the ambient pressure at the deployed depth of the habitat. This latter configuration is used for saturation diving missions. Alternatively, in some applications designed for shallow use only, the radial thickness of the hull wall may be as low as 8 mm.
The series of connected hull wall modules 10, 20 are arranged along a longitudinal axis. That is to say, the longitudinal axis passes through the length of the interior volume 2 of the habitat 1 and the assembled hull 1 has a generally linear configuration. In other words, the hull 1 is of a generally tubular configuration with closed ends. In cross-section, the hull 1 is generally circular, although other hollow cross-sections are possible, such as square cross-sections.
The hull wall modules 10, 20 are supplied in two different variants, each having a different form factor, i.e., different shape. The hull wall module 10 at each end of the hull is designed as an end-cap, i.e., is shaped to provide closed ends to the hollow tube of the hull. The remaining hull wall module(s) 20 disposed between the end-caps 10, are designed as intermediate modules 20. In other words, the one or more hull wall modules 20 are hollow tubes, open at each end such that when the hull 1 is assembled, the end-caps 10 and the intermediate modules 20 together define a single enclosed volume 2. Each end-cap 10 is identical, i.e., the shape and dimensions of the end-caps 10 are identical, although the fit out of each end-cap 10 may be different. Likewise, each intermediate module 20 is identical, i.e., the shape and dimensions of the intermediate modules 20 are identical, although the fit out of each intermediate module 20 may be different. Since only two variants of hull wall module 10, 20 are provided, the size of the habitat can be tailored to the needs of the intended mission without increasing the design or manufacturing complexity; all that needs to be changed is the number of intermediate modules 20 employed and/or the number of complete hulls 1 (each made of the same types of hull wall modules 10, 20). Generally, between 3 and 5 intermediate modules 20 are used per hull 1.
The preferred form factor of the end-caps 10 is that of an open-sided hemisphere or torisphere and that of the intermediate module(s) is a cylinder. Both of these shapes are geometrically strong against internal and external pressures thereby enabling the walls to be made thinner for a given pressure requirement than other shapes. Hemispheres may be used for vessels primarily intended to withstand external pressure whereas torispheres ends may be used for vessels primarily designed to withstand internal pressures only.
Each hull wall module 10, 20 includes a common internal diameter. The internal diameter is at least 2 m and preferably greater than 3 m. This provides a large interior volume 2 for installation of large quantities of bulky equipment. In some embodiments, the internal diameter is between 2-12 m, 3-8 m, or 4-6 m. The length along the longitudinal axis of each module is at least 1 m, and preferably greater than 2 m.
Each hull wall module is made of steel, aluminium, titanium, carbon fibre, acrylic, ceramic, Inconel, Duplex, Super Duplex or combinations thereof. A particular example of Duplex is 1.4462 and a particular example of Super Duplex is 1.4507. Where combinations of material are used, for example steel and Inconel, the hull wall modules may be formed in layers of each material. Where the modules are made of aluminium, titanium, or, in particular, steel, they are made by an additive manufacturing technique, for example, Wire Arc Additive Manufacturing (WAAM). Hull wall modules manufactured by an additive manufacturing technique have improved structural properties compared to hulls manufactured by traditional fabrication techniques (i.e., where the hulls are fabricated from forgings or castings). In particular, the improved uniformity of the hull wall created by additive manufacturing has fewer weak points and is less likely to fail at great risk to any human occupants.
The hull wall modules are connected together via identical mating rings 30. A mating ring 30 is placed between each pair of adjacent hull wall modules 10, 20. A magnified illustration of the joining of two adjacent hull wall modules 20 is shown in
Each mating ring 30 is a generally flat disk having two axial faces 31. Open ends of each hull wall module 10, 20 (i.e., both axial ends of the intermediate modules 20, and the open-sided ends of the end-caps 10) include a projecting flange 22 with an axial face 21. The diameter of the mating ring 30 corresponds to that of the hull wall modules 10, 20. Hence, when assembled, the axial faces 31 of each mating ring 30 are aligned with, and are configured to mate with, the corresponding axial faces 21 of the hull wall modules 10, 20 adjacent the respective mating rings 30.
Each mating ring 30 includes a series of through-holes 34 arranged at equally spaced intervals around its circumference. The flanges 22 of each hull wall module 10, 20 includes a matching series of through-holes 24. In other words, the pattern of through-holes 34 in the mating rings 30 matches that of the flanges. Therefore, when assembled, the through-holes of adjacent mating rings 30 and hull wall modules 10, 20 can be aligned (in triplets of through-holes) so that a bolt 25 or other fastener can be passed through. The bolts are then fastened with nuts to detachably join the adjacent hull wall modules 10, 20 together. This provides a secure, yet releasable way of fastening the hull wall modules 10, 20 together such that they can be disassembled, without cutting, for reconfiguration for a new mission. In addition, the equal spacing of the through-holes means that adjacent modules can be connected a range of rotational orientations with respect to each other.
Where the hull wall modules 10, 20 are made of metal, the connection via the mating ring is configured to be electrically isolating which, for example, limits corrosion, especially where the mating ring 30 is made of a different metal. This achieved by placing an insulating barrier between the adjacent hull wall modules 10, 20. For example, the insulating barrier can be paint coated on the flanges 22, an insulating ceramic or plastic sleeve surrounding the bolt, and/or a plastic insert between the hull wall modules and the mating rings or the bolt.
A particular realisation is shown in
In addition, Duplex washer plates 26 are provided between the bolt-heads and/or nuts and the flanges 22 to spread loads over the surface of the flange 22, rather than concentrating them near the through-holes 24, to thereby by avoid damaging coatings applied to the flanges 22. In order to extend the lifetime of the fastening arrangement, the duplex washer plates 26 are interconnected by connecting wires 29 to maintain continuity.
Each axial face 31 of a mating ring 30 includes a pair of circumferential grooves 32 running around the entirety of the circumference of the mating ring. The circumferential grooves 32 are each sized to house a seal 38, for example, an o-ring. Alternatively, a single groove 32 and a single seal 38 can be used. When assembled and adjacent hull wall modules 10, 20 are tightened towards each other against the intervening mating ring 30, the seals 38 form a watertight seals to prevent water entering the interior volume 2 of the habitat.
By providing the grooves 32 in a mating ring 30, the flanges 22 of all of the hull wall modules 10, 20 can be made identical to each other. As a result, all intermediate modules 20 can be identical and all end-caps 10 can be identical. This simplifies the manufacturing of each hull wall module 10, 20. If a system were provided without a mating ring, some flanges would have to include grooves and others would not so that tooling and manufacturing processes would have to be developed for manufacturing two different types of flanges. In this scenario, not all end-caps 10 and intermediate modules 20 could be made the same. Moreover, it is easier to machine the grooves 32 into the mating rings 30 since the mating rings 30 are comparatively small compared to the hull wall modules 10, 20 and, therefore, easier to manipulate for machining after initial fabrication.
A further advantage of using mating rings is that they permit the use of variants on the hull wall module designs. For example, a different variant of the end-cap 10 could be produced without needing to alter the rest of the design. Thus, the mating rings 30 enable the hull wall modules to be more customisable.
The diameter of the outer edge of each mating 30 is larger than that of the flanges 22 of the hull wall modules 10, 20 such that a portion of each mating ring 30 extends beyond the outer surface of the hull wall modules 10, 20. This portion is equipped with through-holes 36 to which external objects can be bolted to the hull 1. These objects include external insulation, breathing gas cylinders, drinking water/fuel tanks, and batteries, for example. Instead of the through-holes 36, a rail can be provided to which the external objects are able to grip. In addition or alternatively, attachment structures can be formed integrally with the outside surfaces of the hull modules 10, 20.
Each hull wall module 10, 20 includes at least one aperture 40 through a surface thereof. By aperture is meant a hole through the hull wall that is subsequently sealingly fitted with a component, such as a window. In other words, an aperture is not simply a transparent portion continuous with the rest of the hull wall, i.e., where there is no hole. All of the apertures 40 share identical aperture fittings 41 and dimensions. This enables one of a range of interchangeable components to be fitted to each apertures so that each hull wall module can be reconfigured as needed for a given mission. Examples of such interchangeable components are illustrated in
The apertures 40 in the intermediate modules 20 are regularly arranged around its circumference. This arrangement evenly distributes pressure loads applied on the apertures around the hull wall module thereby avoiding asymmetric pressure loads on the hull. In addition, the rotational symmetry facilitates connecting multiple habitat hulls together. Each aperture has a diameter of at least 1 m such that it is possible for a human wearing diving gear to pass safely through. Preferably, however, the diameter is greater than 2 m so that a human can walk through without needing to bend over.
Generally, the hull stiffeners 120 are attached to the outer surface of the hull wall 100. However, they may be provided on an inner surface of the hull wall 100 instead and/or they may be positioned on an outer surface and run around the entire circumference of the hull wall 100 at an axial position where no aperture fittings 41 are present.
The hull stiffeners 120 are welded in place. However, it should be noted that welding here is not detrimental, since the welds are not formed through the thickness of the hull wall, thereby comprising its strength.
The hull stiffeners 120 are not made during the same additive manufacturing process as the hull wall 100 and aperture fittings 41. This is because the apertures are T-shaped and, therefore, include large overhangs. Such shapes are difficult to create using additive manufacturing unless scaffolding is used, which increases manufacturing time and increases material wastage since the scaffolds must subsequently be machined away. Therefore, the hull stiffeners 120 are manufactured in a separate process and welded to the hull wall 100 in a subsequent step.
The hull stiffeners 120 can themselves be manufactured using additive manufacturing, such as WAAM, or forging techniques and are welded to the outer surface of the hull wall 100 after the additive manufacturing process of the hull wall is complete. This post-processing attachment of the hull stiffeners 120 allows for a more efficient additive manufacturing process, as it reduces the material waste that would typically be required for additive manufacturing scaffolding and avoids the need for large overhangs in the additive manufacturing process.
The hull stiffeners may be made of various materials, such as steel, which offers strength and durability suitable for underwater pressure hull applications. Duplex steel is preferred since it provides additional corrosion resistance and improved mechanical properties compared to traditional steel materials.
As shown in
The components of the systems, devices and methods described herein may be utilised and/or manufactured in combination, or separately, in various ways which will be appreciated by the skilled person.
It will be understood that the above description of is given by way of example only and that various modifications may be made by those skilled in the art. Although various embodiments have been described above with a certain degree of particularity, or with reference to one or more individual embodiments, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the scope of this invention.
The following list provides numbered embodiments of the invention and forms part of the description. These embodiments can be combined in any compatible combination beyond those expressly stated. The embodiments can also be combined with any compatible features described herein:
| Number | Date | Country | Kind |
|---|---|---|---|
| 2310866.5 | Jul 2023 | GB | national |
