WO2020214090A1

WO2020214090A1 - Submersible device for sediment accumulation

Info

Publication number: WO2020214090A1
Application number: PCT/SG2020/050228
Authority: WO
Inventors: Heather Marie NELSON; Emile C. THERIAULT-SHAY; Amelia Wei Jung WONG; Nitzan ZILBERMAN; Schendy KERNIZAN; Jared LAUCKS; Bjorn SPARRMAN; Skylar TIBBITS
Original assignee: Massachusetts Institute Of Technology; MANIKU, Hassan; DOLE, Sarah Y.; MATTEUCCI, Gianfranco
Priority date: 2019-04-15
Filing date: 2020-04-14
Publication date: 2020-10-22

Abstract

The present disclosure generally relates to a submersible device (100) and a method (200) for facilitating accumulation of sediments (60). The device (100) comprises a device body (102) comprising an internal chamber (104) fillable for defining a geometrical profile of the device body (102). The device (100) when submerged in the water body (50) diverts a water current in the water body (50) flowing against the device (100), the diverted water current transporting sediments (60) that accumulate around the device (100).

Description

SUBMERSIBLE DEVICE FOR SEDIMENT ACCUMULATION

Cross Reference to Related Application(s)

The present disclosure claims the benefit of United States Patent Application No. 62/834,01 1 filed on 15 April 2019, which is incorporated in its entirety by reference herein.

Technical Field

The present disclosure generally relates to a submersible device for sediment accumulation. More particularly, the present disclosure describes various embodiments of a device that is submersible in a water body for facilitating accumulation of sediments around the device to eventually grow geological formations such as shoals or sandbars.

Background

Climate change and rising sea levels are creating an imminent and growing threat to island nations and coastal regions. The rise of sea levels from global warming and melting of sea ice causes inundation of coastal regions. Increasing frequency and severity of storms may further batter and erode coastlines. Increased ocean temperatures also contribute to the loss of coral reefs which protect coastal integrity. As more than 40% of the world’s population live near coastlines, there is an urgency to address the imminent threatening effects of climate change such as coastal erosion. Conventional approaches to combat coastal erosion involve static physical barriers or continual coastal dredging. However, these approaches are expensive and destructive as they resist the forces of nature which are constantly changing, potentially harming surrounding ecosystems and marine life. For example, one method to replenish eroding beaches is to continually deposit dredged material along shorelines. This may be done using mechanical or hydraulic dredges or excavators that pick up material from the seabed or riverbed and transports the dredged material to the shorelines. Notwithstanding that dredges are costly, this method of abruptly transporting and relocating material from the seabed or riverbed to the shorelines, which are already vulnerable to climate change, further disrupts fragile marine environments, thereby further accelerating coastal erosion.

Therefore, in order to address or alleviate at least one of the aforementioned problems and/or disadvantages, there is a need to provide an improved approach to combatting coastal erosion. Specifically, the present disclosure describes a submersible device and a method for facilitating accumulation of sediments to eventually reconstruct eroding geological formations.

Summary

According to a first aspect of the present disclosure, there is a device submersible in a water body for facilitating accumulation of sediments. The device comprises a device body comprising an internal chamber tillable for defining a geometrical profile of the device body. When submerged in the water body, the device diverts a water current in the water body flowing against the device, the diverted water current transporting sediments that accumulate around the device.

According to a second aspect of the present disclosure, there is a system for facilitating accumulation of sediments. The system comprises: a network of devices submersible in a water body having a water current, each submersible device comprising a device body having an internal chamber tillable for defining a geometrical profile of the device body; and an external control system communicatively coupled to the network of devices for remotely controlling the submersible devices. When submerged in the water body, the devices divert the water current flowing against the respective device, the diverted water current transporting sediments that accumulate around the respective device.

According to a third aspect of the present disclosure, there is a method for facilitating accumulation of sediments. The method comprises: engaging a water current in a water body by a device submerged in the water body, the device comprising a device body having an internal chamber tillable for defining a geometrical profile of the device body; diverting the water current by the submerged device; transporting sediments by the diverted water current; and accumulating the sediments around the submerged device.

A submersible device and a method for facilitating accumulation of sediments according to the present disclosure are thus disclosed herein. Various features, aspects, and advantages of the present disclosure will become more apparent from the following detailed description of the embodiments of the present disclosure, by way of non-limiting examples only, along with the accompanying drawings.

Brief Description of the Drawings

Figure 1 is an illustration of a device submersible in a water body for facilitating accumulation of sediments, in accordance with embodiments of the present disclosure.

Figure 2A to Figure 2D are illustrations of interactions in the water body for transport of sediments in a natural environment.

Figure 3A to Figure 3D are illustrations of the transport of sediments across the device having a ramp-like geometrical profile, in accordance with some embodiments of the present disclosure.

Figure 4 is a flowchart illustration of a method for facilitating accumulation of sediments using the device, in accordance with embodiments of the present disclosure.

Figure 5A is an illustration of a laboratory experiment for facilitating accumulation of sediments using the device submerged in the water body, in accordance with some embodiments of the present disclosure. Figure 5B is an illustration of a network of the devices submerged in the water body for facilitating accumulation of sediments, in accordance with some embodiments of the present disclosure.

Figure 5C is an illustration of a field experiment for facilitating accumulation of sediments using several devices submerged in the water body, in accordance with some embodiments of the present disclosure.

Figure 6 is an illustration of a series of the devices joined together, in accordance with some embodiments of the present disclosure.

Figure 7 A to Figure 7F are illustrations of the devices having various geometrical profiles and arrangements for facilitating accumulation of sediments, in accordance with various embodiments of the present disclosure.

Figure 8 is an illustration of a process for forming the device, in accordance with some embodiments of the present disclosure.

Figure 9A and Figure 9B are illustrations of various arrangements of fillable bladders in an internal chamber of the device, in accordance with some embodiments of the present disclosure.

Figure 10A is an illustration of the device communicatively coupled to a sea vessel and having an internal water pump for filling the bladders, in accordance with some embodiments of the present disclosure.

Figure 10B is an illustration of the device connected to an external gas source for inflating the bladders, in accordance with some embodiments of the present disclosure.

Detailed Description For purposes of brevity and clarity, descriptions of embodiments of the present disclosure are directed to a submersible device and a method for facilitating accumulation of sediments, in accordance with the drawings. While aspects of the present disclosure will be described in conjunction with the embodiments provided herein, it will be understood that they are not intended to limit the present disclosure to these embodiments. On the contrary, the present disclosure is intended to cover alternatives, modifications and equivalents to the embodiments described herein, which are included within the scope of the present disclosure as defined by the appended claims. Furthermore, in the following detailed description, specific details are set forth in order to provide a thorough understanding of the present disclosure. Flowever, it will be recognized by an individual having ordinary skill in the art, i.e. a skilled person, that the present disclosure may be practiced without specific details, and/or with multiple details arising from combinations of aspects of particular embodiments. In a number of instances, known systems, methods, procedures, and components have not been described in detail so as to not unnecessarily obscure aspects of the embodiments of the present disclosure.

In embodiments of the present disclosure, depiction of a given element or consideration or use of a particular element number in a particular figure or a reference thereto in corresponding descriptive material can encompass the same, an equivalent, or an analogous element or element number identified in another figure or descriptive material associated therewith.

References to“an embodiment / example”,“another embodiment / example”,“some embodiments / examples”, “some other embodiments / examples”, and so on, indicate that the embodiment(s) / example(s) so described may include a particular feature, structure, characteristic, property, element, or limitation, but that not every embodiment / example necessarily includes that particular feature, structure, characteristic, property, element, or limitation. Furthermore, repeated use of the phrase“in an embodiment / example” or“in another embodiment / example” does not necessarily refer to the same embodiment / example. The terms “comprising”, “including”, “having”, and the like do not exclude the presence of other features / elements / steps than those listed in an embodiment. Recitation of certain features / elements / steps in mutually different embodiments does not indicate that a combination of these features / elements / steps cannot be used in an embodiment.

As used herein, the terms“a” and“an” are defined as one or more than one. The use of 7” in a figure or associated text is understood to mean“and/or” unless otherwise indicated. The term“a number of” and“a set of” are defined as a positive integer that is equal to one or greater than one. In other words, as used herein, a number of or a set of elements means at least one element. The recitation of a particular numerical value or value range herein is understood to include or be a recitation of an approximate numerical value or value range.

Representative or exemplary embodiments of the present disclosure as shown in Figure 1 describe a device 100 that is submersible in a water body 50 for facilitating accumulation of sediments 60. The process of accumulation of sediments 60 is more clearly illustrated in Figure 3A to Figure 3D and is described further below. As shown in Figure 1 , the device 100 includes a device body 102 having an internal chamber 104 - a hollow portion within the device body 102 - that is tillable for defining a geometrical profile of the device body 102 and for submerging the device 100 in the water body 50. For example, the internal chamber 104 may be filled with material, such as sand and water, to define the geometrical profile of the device body 102 and to increase the overall density of the device 100 and thus submerge the device 100 in the water body 50. The geometrical profile refers to various geometrical properties of the device body 102, such as but not limited to, size, shape, form, orientation, geometry, inclination, length, width, and height. The internal chamber 104 may be arranged to house various other components to assist in the process of accumulation of sediments 60, as described further below.

When the device 100 is submerged in the water body 50, the bottom of the device 100 is in contact with a bed or floor 52 of the water body 50 (e.g. seabed) and is at least partially underwater. As used herein, the term“submerged” does not require that the whole of the device 100 be completely underwater, i.e. the top of the device 100 is below the surface of the water body 50. The device 100 is submerged if at least a portion of the device 100 is underwater and the bottom of the device 100 contacts the bed 52. In the water body 50, the submerged device 100 obstructs a water current in the water body 50 flowing against the submerged device 100. The water current refers to the rate of movement of water in the water body 50, and may be described in terms of velocity, i.e. speed and direction. The obstruction of the water current by the submerged device 100 diverts the water current around the submerged device 100. The diverted water current carries and transports the sediments 60, accumulating the sediments 60 around the submerged device 100.

The water body 50 may be, but not limited to, a sea, lake, lagoon, river, stream, or part thereof. The sediments 60 include material or matter inside the water body 50, such as but not limited to sand, silt, soil, stones, gravel, and rocks. In a natural environment, transport of the sediments 60 in the water body 50 can be driven by at least four types of interactions between the water current and the bed 52, as explained below with reference to Figure 2A to Figure 2D.

As shown in Figure 2A, one type of interaction results in the shear stress effect, wherein the water current has enough velocity to reach a threshold shear stress between the water and the bed 52, thereby transporting the sediments 60 across the bed 52. In some situations, the water body 50 may have some natural geological formations 54 formed on the bed 52. As shown in Figure 2B, one type of interaction results in the wrap-around effect, wherein the water current flows around a geological formation 54 such as a protruding sand formation. This creates turbulent flow which disrupts the bed 52 around the geological formation 54, thereby transporting the sediments 60 to behind the geological formation 54. As shown in Figure 2C, one type of interaction results in the channel effect, wherein the water current flows through a channel 56 formed through the geological formation 54. The channel 56 creates a narrower path for the water current which increases the velocity of the water current flowing through the channel 56. The shear stress effect mentioned above is triggered when the water current reaches a sufficiently high velocity, thereby transporting the sediments 60 across the channel 56 via laminar flow. When the water current exits the channel 56, the water current is distributed and this distribution of the water current’s momentum creates turbulent flow. This turbulent flow disrupts the bed 52 around the channel exit and transports the sediments 60 near the channel exit. As shown in Figure 2D, one type of interaction results in the ramp effect, wherein the water current flows upwards along a geological formation 54 having a ramp-like structure. As the water current flows over the ramp-like geological formation 54, the vertical drop at the end causes turbulent flow where the bed 52 flattens. This turbulent flow disrupts the bed 52 and transports the sediments 60 to behind the ramp-like geological formation 54.

In some embodiments, the device 100 has device body 102 with a ramp-like geometrical profile like the geological formation 54 shown in Figure 2D. Particularly, such a device body 102 includes a front end 106, a rear end 108, and an ascending region 1 10 from the front end 106 to the rear end 108. When the device 100 is submerged in the water body 50, the water current flows against the front end 106 and upwards along the ascending region 1 10. The sediments 60 are transported by the water current and the sediments 60 accumulate behind the rear end 108. This transport of sediments 60 across the ramp-like device 100 is elaborated below with reference to Figure 3A to Figure 3D.

As shown in Figure 1 , the ramp-like device 100 has an overall length (along the x- axis), width (from the front end 106 to the rear end 108 along the y-axis), and height (along the z-axis). The overall height of the device 100 may be at least 2m. Preferably, the overall height of the device 100 is approximately aligned with the surface of the water body 50 when the device 100 is submerged to the bed 52. Flowever, it will be appreciated that conditions of the water body 50 can change quickly and the device 100 may be fully submerged at times and partially submerged at others. The overall width of the device 100 may be at least 2m. Additionally, the gradient percentage of the ascending region 1 10 may range from 50% to 100%. Preferably, the gradient percentage is 50% and the overall width is approximately twice the overall height. The gradient percentage should not exceed 100% otherwise that would hinder transportation of sediments 60 across the steep ascending region 1 10. The overall length of the device 100 may be at least 3m, preferably at least 10m, and more preferably at least 20m. Multiple devices 100 may be joined adjacent to each other (along the x-axis) to extend the overall length of the devices 100. While the wrap-around effect helps to transport sediments 60 around the device(s) 100, it can have a negative effect at the both lengthwise ends where accumulated sediments 60 can get displaced. If the length is too short, such as less than 10m, the displaced sediments 60 can have a significant negative impact on the accumulation of sediments 60 around the device(s) 100. Multiple devices 100 may be joined adjacently to each other (along the x-axis) to extend the total length to at least 10m and preferably at least 20m.

As shown in Figure 3A, the device 100 is submerged in the water body 50. The device 100 is partially submerged in the water body such that the part of the rear end 108 rises above the water surface. The device 100 is arranged on the bed 52 such that the rear end 108 faces the desired location for accumulation of sediments 60. As shown in Figure 3B, the device 100 diverts the water current and the water current flows upwards along the ascending region 1 10 and drops off over the rear end 108, creating turbulent flow or eddies at the bed 52 behind the rear end 108. This turbulent flow disrupts the bed 52 and displaces the sediments 60 and accumulates them at a small distance behind the rear end 108. As shown in Figure 3C, when the water current has a sufficiently high velocity, the shear stress effect is created and more sediments 60 are displaced across the ascending region 110 and over the rear end 108. The sediments 60 then accumulate to fill the gap behind the rear end 108. As shown in Figure 3D, both types of interactions continue to transport sediments 60 and accumulate them at the desired location behind the device 100.

Therefore, the device 100 submerged in the water body 50 diverts the water current flowing against the submerged device 100. The diverted water current transports sediments 60 that accumulate around the submerged device 100, such as at the desired location behind the rear end 108. Eventually, the accumulated sediments 60 at the desired location naturally grows into a geological formation 70, which may grow to such size that it breaches the water surface, forming a shoal or sandbar on the water surface.

In various embodiments of the present disclosure, there is a method 200 for facilitating accumulation of sediments 60 using the device 100, as shown in Figure 4. The method 200 includes a step 202 of engaging the water current in the water body 50 by the device 100 submerged in the water body 50. The method 200 include a step 204 of diverting the water current by the submerged device 100. The method 200 include a step 206 of transporting sediments 60 by the diverted water current. The method 200 include a step 208 of accumulating the sediments 60 around the submerged device 100. The method may further include an initial step of submerging the device 100 in the water body 50 such that the water current flows against the device 100.

The sediments 60 accumulate around the device 100 and the accumulated sediments 60 eventually and naturally grow into a geological formation 70. If the device 100 is deployed near a beach or shoreline, the sediments 60 would accumulate towards the beach or shoreline and the geological formation 70 may eventually grow to join with the beach or shoreline. One example of the geological formation 70 is a shoal which is rises from the bed of a water body to the water surface and is typically covered by sand. Shoals are also known as sandbanks, sandbars, or gravelbars. The use of the device 100 submerged in the water body 50 advantageously allows the sediments 60 to accumulate and the geological formations 70 to grow naturally by relying on natural water current in the water body 50. The device 100 cooperates with forces of nature and harnesses them to construct rather than destruct which would be the case of conventional approaches such as coastal dredging.

A laboratory experiment was performed using a device 100 having a ramp-like geographical profile and the device 100 was submerged in a water body 50. The process of this experiment is illustrated in Figure 5A. The device 100 diverts the water current flowing against the device 100 and the diverted current transports sediments 60 around the device 100. After a period of time, the sediments 60 continually accumulate behind the device 100. This experiment shows that the device 100 is effective in facilitating accumulation of sediments 60. The device 100 can be deployed in a water body 50, such as a sea or river, to accumulate the sediments 60 around the device 100. The accumulated sediments 60 would eventually grow in size and form a geological formation 70.

To improve the rate of forming the geological formation 70, a network of a plurality of devices 100 may submerged in the water body 50 and arranged to accumulate sediments at the desired location. The network of devices 100 may be dispersedly distributed on the bed 52, i.e. each device 100 is physically separated from the other devices 100, such as shown in Figure 5B. Each device 100 may be fabricated to have an elongated profile, or alternatively two or more devices 100 may be joined to form a series of devices 100, such as shown in Figure 6.

In the arrangement as shown in Figure 5B, several devices 100 are distributed in the water body 50 in a predetermined arrangement, wherein this arrangement may be determined based on prevailing data on climate, weather, and water conditions of the environment where the devices 100 are deployed. The devices 100 may be arranged such that they collectively span a total distance of several tens of metres or several kilometres. This allows the devices 100 to collectively facilitate accumulation of sediments 60 which may then aggregate to form geological formations 70. More particularly, the devices 100 are arranged such that the sediments 60 are targeted to accumulate near an island or coastline, so that the geological formations 70 such as shoals can eventually grow and protect the island or coastline.

A field experiment was performed using several devices 100 joined together to achieve an overall length of 20m and an overall width of 4m. As shown in Figure 5C, the devices 100 were installed in a water body 50 and this field experiment continued over a period of around 6 months. The results of this field experiment showed that sediments 60 accumulate behind the devices 100 over the time period and would eventually grow into a geological formation 70. In some embodiments, the device 100 may have the device body 102 that does not have a ramp-like geometrical profile but instead has a different form or shape. Multiple devices 100 may also be arranged in a specific arrangement in the water body 50 for accumulation of sediments 60, such as to target sediment accumulation at a specific location. In one embodiment as shown in Figure 7A, there are two (or more) devices 100, or alternatively two (or more) series of devices 100, submerged in the water body 50. The water current in the water body 50 has converging waves coming from opposing directions, each wave interacting with one of the devices 100. Such an arrangement of the devices 100 facilitates accumulation of sediments 60 at the intersection of the converging waves between the devices 100. In one embodiment as shown in Figure 7B, the water current has a predominant wave direction and two (or more) devices 100, or alternatively two (or more) series of devices 100, are submerged in the water body 50 such that they are angled relative to the predominant wave direction. This angled arrangement promotes a dual wrap around effect and targets the sediment accumulation at a central common region behind the devices 100.

In some embodiments, the device 100 may have the device body 102 that does not have a ramp-like geometrical profile but instead has a different form or shape. In one embodiment, the device body 102 has a cylindrical shape arranged horizontally in the water body 50, and the accumulation of sediments 60 around the device 100 having a cylindrical device body 102 is shown in Figure 7C. In one embodiment as shown in Figure 7D, the device body 102 has a curved or crescent-like shape, which can be extrapolated to a C-shape or U-shape. In one embodiment as shown in Figure 7E, the device body 102 has a hemispherical or dome-like shape. Like the ramp-like shape, the crescent-like shaped and dome-like shaped devices 100 may have an overall height of at least 2m, overall width of at least 2m, and overall length of at least 3m, and preferably includes an ascending region 1 10 to facilitate transportation of sediments 60. In one embodiment as shown in Figure 7F, multiple devices 100 are submerged in the water body 50 and each device body 102 has a teardrop or droplet shape. Each device body 102 has the front end 106 and rear end 108 near the wider part and narrower part, respectively, of the teardrop shape. The water current flows against the front ends 106 and the devices 100 divert the water current to accumulate sediments 60 around the devices 100.

The device body 102 is made from a suitable material that may be rigid or flexible. The material should be resistant to corrosion as the device 100 is submersible in the water body 50 which may contain saline or salt water. Moreover, the material should not include foam or the like as that would significantly increase the buoyancy of the device 100, making it more difficult to submerge the device 100. In one example, the material is a natural material such as wood. In another example, the material is a synthetic material such as a biodegradable fabric or textile material that preferably can attract growth of marine life like algae and corals. In yet another example, the material is a metal or metallic alloy such as steel. It will be appreciated that the suitable material for the device body 102 is not limited to the examples described above, and may include other types of materials known to the skilled person.

Depending on the types of materials used for the device body 102 as well as other parts of the device 100, various manufacturing methods may be preferred as will be readily understood by the skilled person. Some non-limiting examples of manufacturing methods include welded metal fabrication, injection moulding, additive manufacturing such as 3D printing and engineered knitting, cutting and sewing textiles, concrete casting, wood fabrication, or any combination thereof.

In one embodiment, the device body 102 is made from a fabric material such as duck canvas. The device body 102 may be made from a single piece of duck canvas, or alternatively from several pieces of duck canvas joined by various means such as stitching. Figure 8 illustrates a process 300 of forming the device 100 from the raw duck canvas pieces of the device body 102.

In step 302, the material for the device body 102 is formed from duck canvas 1 12 and this may be formed from a single piece of duck canvas or several pieces of duck canvas joined by stitching. In step 304, the duck canvas 1 12 is folded together so that it can be easily transported. The unfolded duck canvas 1 12 may have dimensions 3m x 3.6m while the folded duck canvas 1 12 may have dimensions 0.9m by 1.5m. In step 306, the folded duck canvas 1 12 is transported, such as by a sea vessel, to the water body 50 for deployment. The sea vessel may be a boat, barge, buoy, ship, or the like.

In step 308, the folded duck canvas 1 12 is unfolded on the sea vessel (or on the water body 50 around the sea vessel) to form the device body 102 including the internal chamber 104. Granular material 1 14, such as sand, are transferred into the device body 102 to fill the internal chamber 104. The granular material 1 14 may be transferred from a sand dredging excavator located away from the sea vessel, such as through a pipe connection having a length such as 500m. A frame structure may be attached to the device body 102 for stabilizing the device body 102, specifically to support the duck canvas 1 12 while the internal chamber 104 is being filled. In one example, the frame structure is attached externally to the device body 102, such as by straps / ties or through sleeves that are attached to the device body 102. In another example, the frame structure is disposed within the device body 102, such as within the internal chamber 104 or by lining the inside of the device body 102. Such an internal frame structure may be collapsible and expands when the internal chamber 104 is being filled.

Filling the internal chamber 104 with the granular material 1 14 solidifies the device body 102 and maintains the geometrical profile of the device body 102, such as a ramp profile as shown in Figure 8. The filled device body 102 has a length of 3m, a width of 3m from the front end 106 to the rear end 108, a height of 2m, and a hypotenuse length of 3.6m along the ascending region 1 10. In step 310, one or more straps 1 16 are removably attached to the device body 102 to secure the device body 102. Specifically, the straps 1 16 are tied around the device body 102 to secure the geometrical profile of the device body 102. Further, the straps 1 16 can be tethered to the sea vessel for transporting the device 100, such as to another location for redeployment or back to shore for packing / storage.

In step 312, the device 100 including the device body 102, straps 116, and optionally the frame structure stabilizing the device body 102, is submerged into the water body 50 such that the bottom of the device 100 contacts the bed 52. The submerged device 100 thus diverts the water current in the water body flowing against the front end 106, wherein the diverted water current transports sediments 60 that accumulate around the submerged device 100, specifically behind the rear end 108.

In addition to securing the device body 102, the straps 1 16 may be configured to adjust the geometrical profile of the device body 102. For example in step 314, the duck canvas 1 12 and straps 1 16 are adjusted to increase the gradient of the ramp shaped device 100. For example in step 316, the duck canvas 1 12 and straps 1 16 are adjusted to form a depression 1 18 in the device body 102, the depression 1 18 simulating a channel or funnel for more directed water movement, possible triggering the channel effect described above. For example in step 318, the duck canvas 1 12 and straps 1 16 are adjusted to change the width and/or height of the device body 102, such as to accommodate tide changes which affect the water surface level relative to the bed 52. It will be appreciated that the duck canvas 112 and straps 1 16 may be adjusted cooperatively in various ways to adjust the geometrical profile of the device body 102, which may be suitable to improve accumulation of sediments 60 at desired locations and to facilitate growth of geological formations 70 at these locations.

In one embodiment, four devices 100 are joined in a series as shown in Figure 6. Each device body 102 has a ramp profile, a length of 2.5m, a width of 4m, a height of 2m, and a hypotenuse length of 4.5m. The total length of the joined devices 100 is thus 10m. Each device 100 has a conjoining mechanism attached to the respective device body 102 for attaching the respective device 100 to another device 100, specifically to the corresponding conjoining mechanism of the other device 100. The conjoining mechanism may be in the form of mechanical couplings as will be readily known to the skilled person, such as but not limited to fasteners, latches, clips, adhesive means, etc. As shown in Figure 6, the conjoining mechanism is in the form of loops 120 stitched to the device body 102 and loops 120 of adjacent devices 100 can be tied to each other. It will be appreciated that a different number of devices 100 may be joined together, such as to achieve a total length of at least 20m. Each device 100 has a number of inlets 122 (i.e. at least one inlet 122) and a number of outlets 124 (i.e. at least one outlet 124) disposed on the device body 102. In some embodiments, the device 100 has one inlet 122 and one outlet 122. In some embodiments, the device 100 has a plurality of inlets 122 and one outlet 124. In some embodiments, the device 100 has one inlet 122 and a plurality of outlets 124. In some embodiments, the device 100 has a plurality of inlets 122 and a plurality of outlets 124. Without imposing any limitation on the number of inlets 122 / outlets 124, the following description referencing the inlets 122 and outlets 124 should be taken to mean at least one inlet 122 and at least one outlet 124.

The inlets 122 and outlets 124 are configured for transferring material into and out of the internal chamber 104, respectively. For example, each device 100 may have a single inlet 122 for transferring granular material 1 14 to fill the internal chamber 104 to thereby submerge the device 100, as well as a single outlet 124 for removing the granular material 1 14 to evacuate the internal chamber 104 to thereby float the device 100.

In one example as shown in Figure 6, each device 100 has a partition arranged horizontally in the internal chamber 104. The horizontal partition separates the internal chamber 104 into an upper chamber and a lower chamber. The device 100 has an upper inlet 122a, a lower inlet 122b, an upper outlet 124a, and a lower outlet 124b. The upper inlet 122a and upper outlet 124a are configured for transferring granular material 1 14 into and out of the upper chamber. The lower inlet 122b and lower outlet 124b are configured for transferring water into and out of the lower chamber relative to the water body 50. The inlets 122 may have a diameter of 200mm and may be formed from a fabric material, such as canvas. The outlets may have a diameter of 100mm and may be formed from a plastic material, such as polyethylene or FIDPE.

In some embodiments, the device 100 includes a plurality of bladders 126 disposed within the internal chamber 104 of the device body 102, wherein each bladder 126 tillable such that the bladders 126 collectively fill the internal chamber 104. The bladders 126 may be of various sizes and shapes, such as but not limited to cylindrical, polygonal, and spherical. An exemplary arrangement of the bladders 126 in the internal chamber 104 of a ramp-like device 100 is shown in Figure 9A. The bladders 126 may be held within the internal chamber 104 by physical attachment to the inner lining or surface of the device body 102. Each bladder 126 may be formed with an elastic material such that it is expandable when it is filled. For example, the bladders 126 expand like a balloon when they are inflated with a gas, e.g. air or other gaseous matter. The elastic material may be, but is not limited to, an elastomer material. Partitions may be included in the internal chamber 104 to separate the bladders 126 into different sections of the internal chamber 104. For example as shown in Figure 1 and Figure 9A, vertical partitions separate the bladders 126 into a front section 104a, a middle section 104b, and a rear section 104c. Similarly, horizontal partitions may separate the bladders into an upper section 104x, a middle section 104y, and a lower section 104z.

The device 100 includes a number of inlets 122 and a number of outlets 124 disposed on the device body 102 and configured for fluid communication with the bladders 126. Each bladder 126 is tillable selectively between water and gas via the inlets 122 and outlets 124. Selecting between water and gas to fill each bladder 126 varies the size and shape of the bladder 126, thus adjusting the geometrical profile of the device body 102. Said selecting also varies the overall weight and density of the device 100, thereby controlling buoyancy of the device 100. For example, filling the bladders 126 with water raises the density and submerges the device 100 into the water body 50 onto the bed 52. Conversely, inflating the bladders 126 with gas and consequently evacuating the water inside reduces the density and floats the device 100. The floated device 100 can be transported by the sea vessel to another location for redeployment or back to shore for packing / storage if the device 100 is not needed anymore. It will be appreciated that filling of the bladders 126 between water and gas to control buoyancy of the device 100 for ascension / descension is analogous to the operation mechanism of a submarine ballast system.

The device 100 may further include a ballast to assist submersion of the device 100. Particularly, filling the bladders 126 with water may not weigh the device 100 sufficiently to submerge the device 100 in the water body 50. The ballast increases the weight of the device 100 and submerges the device 100, holding it down on the bed 52 to resist storms and strong water current. The ballast may be in the form of weighted objects disposed within the internal chamber 104 or externally and removably attached to the device body 102. The ballast may also be in the form of anchors removably tied to the device body 102, such as to the straps 1 16, to anchor the device 100 to the bed 52.

As mentioned above as well, a frame structure may be removably attached to the device body 102 for stabilizing the device 100 in the water body 50. The frame structure provides additional support to the device 100 on the bed 52 to resist storms and strong water current so that the device 100 does not undulate or move back and forth when the water current interacts with it. The frame structure may be made of mechanical elements such as rods, tubes, pipes, or beams, connected together. The frame structure may be made of a suitable material that is resistant to water or seawater, such as a suitable metallic alloy or a plastic material like PVC. The frame structure may be attached to the device body 102 by passing through sleeves attached to the device body 102. The sleeves, such as the loops 120 mentioned above, may be attached by sewing onto the edges of the device body 102. The frame structure can be easily detached from the device body 102 by removing the mechanical elements from the sleeves. It will be appreciated that the frame structure described above in relation to Figure 8 may be similarly applicable here and is not further described for purpose of brevity.

The inlets 122 are connected to the water body 50 for supplying water from the water body to fill the bladders 126 and connected to a gas source for supplying gas to inflate the bladders 126. Each inlet 122 and outlet 124 is selectable between an open state and a closed state. The outlets 124 are selected to the closed state when the bladders 126 are being filled with water from the water body 50 via the inlets 122. To evacuate the water in the bladders 126, the outlets 124 are selected to the open state and the inlets 122 pump gas into the bladders 126 to push the water out the open outlets 124. To inflate the bladders 126, the outlets 124 are selected to the closed state and the inlets 122 continue to pump gas into the bladders 126. In one embodiment, all the bladders 126 are fluidically connected to each other to enable continuous fluid communication between the bladders 126. For example, tubes connect the bladders 126 together such that they are always in fluid communication with each other. Water or gas and thus readily communicate between the bladders 126 via the tubes. Filling the first bladder 126 that is nearest the inlets 122 with water or gas consequently fills the remaining bladders 126.

In one embodiment, the device 100 has a sole port that functions both as an inlet 122 and an outlet 124. The bladders 126 are fluidically connected to each other to enable continuous fluid communication between the bladders 126, and further fluidically connected to the sole port for filling and evacuating the bladders 126. To submerge the device 100, water is pumped in from the water body 50 into the bladders 126 via the sole port. To float the device 100, the water in the bladders 126 is first discharged from the sole port and the sole port is connected to a gas source. The gas source then pumps gas into the bladders 126 via the sole port to inflate the bladders 126.

In one embodiment, the bladders 126 are fluidically connected to each other via solenoid valves. Specifically, each bladder 126 is fluidically connected to one or more adjacent bladders 126 via respective solenoid valves, each valve selectable between an open state and a closed state. A valve in the open state enables fluid communication between the respective bladders 126 through the open valve, while a valve in the closed state prevents fluid communication between the respective bladders 126. Each bladder 126 has at least one valve acting as an inlet (inlet valve) and at least one valve acting as an outlet (outlet valve). By selecting the states of each valve of each bladder 126, each bladder 126 can be filled independently of the other bladders 126. For example, a few bladders 126 can be filled with water or gas but adjacent bladders 126 can remain unfilled. Some bladders 126 can be filled with just water while other bladders 126 can be filled with just gas. The bladders 126 are independently tillable by selecting each valve between the open and closed states.

As an example to illustrate the mechanism of the inlet and outlet valves, a bladder 126 has an inlet valve and an outlet valve fluidically connected to respective other bladders 126. The inlet and outlet valves are selected to the open and closed states respectively when the bladder 126 is being filled with water via the open inlet valve. Notably, the closed outlet valve prevents the water from communicating to the adjacent bladder 126 which the outlet valve connects to, allowing the bladder 126 to fill with water independently of the adjacent bladder 126. To evacuate the water in the bladder 126, the outlet valve is selected to the open state and the open inlet valve now communicates gas into the bladder 126 to push the water out the open outlet valve. To inflate the bladder 126, the outlet valve is selected to the closed state and the open inlet valve continues to communicate gas into the bladder 126.

In another example, the bladder 126 as two inlet valves and one outlet valve. The first inlet valve is configured to fill the bladder 126 with water while the second inlet valve is configured to inflate the bladder 126 with gas, so that the bladder 126 can be filled selectively between water and gas. The second inlet valve and outlet valve are selected to the closed state and the first inlet valve is selected to the open state when the bladder 126 is being filled with water via the open first inlet valve. To evacuate the water in the bladder 126, the second inlet valve and outlet valve are selected to the open state, the first inlet valve is selected to the closed state, and the open second inlet valve communicates gas into the bladder 126 to push the water out the open outlet valve. To inflate the bladder 126, the outlet valve is selected to the closed state, the first inlet valve remains in the closed state, and the open second inlet valve continues to communicate gas into the bladder 126.

In some other examples, the bladder 126 may have one inlet valve and two (or more) valves, or the bladder 126 may have two (or more) inlet valves and two (or more) outlet valves. It will be appreciated that various combinations / permutations of the solenoid valves are possible such that there can be various ways to fill each bladder 126 selectively between water and gas to thereby adjust the geometrical profile of the device body 102 and control the buoyancy of the device 100.

Independent filling of the bladders 126 with water or gas allows some freedom in adjusting the geometrical profile of the device body 102. The arrangement of the bladders 126 in the internal chamber 104, and possibly with the assistance of partitions separating the bladders 126, facilitates said adjusting of the geometrical profile of the device body 102. With reference to the ramp-like device 100 as shown in Figure 9A, the geometrical profile can be adjusted to achieve various results, such as to increase the overall height of the device 100 and to adjust the slope angle or gradient of the ramp (steeper or gentler). Adjusting the geometrical profile caters the device 100 to different depths of the water body 50 and to optimize the device 100 for various water depths as well as varying forces from the water current. Various adjusted geometrical profiles of the ramp-like device body 102 are shown in Figure 9A and Figure 9B. Notably, the geometrical profile may be adjusted from a ramp-like structure to a rectangular structure as shown in Figure 9B.

As described above, the bladders 126 can be filled with water and gas from the water body 50 and from a gas source, respectively. As shown in Figure 10A, the device 100 may include a water pump 128 housed within the internal chamber 104. The water pump 128 is fluidically connected to an inlet 122 exposed to the water body 50 and is configured to fill the bladders 126 with water. Specifically, the water pump 128 (or other similar mechanism) takes in water from the water body 50 via the inlet 122 and communicates the water to the bladders 126. The device 100 may include a gas source housed within the internal chamber 104. The gas source may be an air compressor fluidically connected to the bladders 126 and configured to discharge air to inflate the bladders 126. The water pump 128 / air compressor may be secured to the device body 102 by suitable fastening mechanisms and may be protected in waterproof enclosures.

In one embodiment as shown in Figure 10B, instead of housing a gas source or air compressor in the device 100, the device 100 is connected to an external gas source 130 for inflating the bladders 126. Underwater gas lines 132 are connected from the external gas source 130 to the inlet 122 to inflate the bladders 126 with gas from the external gas source 130. The external gas source 130 may be an air compressor or air pump stationed on the sea vessel or on nearby land. Instead of being on the sea vessel, the external gas source 130 may be housed in a waterproof structure and may be partially underwater, wherein the external gas source 130 has an air intake rising above the water surface for receiving air from the atmosphere and communicating the air to the device inlet 122. It will be appreciated that the device 100 may utilize a combination of one or more of the water pump 128, internal air compressor, and external gas source 130 to fill the bladders 126 selectively between water and gas.

In some embodiments as shown in Figure 1 , the device 100 includes an electronic unit 134 attached to the device body 102. The electronic unit 134 may be housed in a waterproof casing to protect various electronic components of the electronic unit 134. The electronic unit 134 includes a set of sensors (i.e. at least one sensor) configured to measure physical parameters related to water body 50. In one embodiment as shown in Figure 10A, the sensors include one or more force sensors 136 for measuring forces exerted by the water body 50 directly on the device 100. Specifically, the water current or waves exert forces directly on the device 100 and the magnitude of these forces is measured by the force sensors 136. It will be appreciated that the force sensors 136 may be replaced with similar sensors such as pressure or strain gauge sensors that measure similar parameters related to force.

The sensors may include one or more tilt sensors 138 for measuring forces of the water current surrounding the device 100. Specifically, the tilt sensors 138 measure the forces from the surrounding water current or waves, while the force sensors 136 measure the forces directly applied on the device 100. The sensors may include one or more depth sensors, such as bathometers, for measuring the depth of the water body 50 and the depth of the device 100 when it is submerged in the water body 50, i.e. how deep is the device 100 underwater.

In one embodiment, the electronic unit 134 is powered by an internal battery. In another embodiment as shown in Figure 10A, the electronic unit 134 is connected to the sea vessel 140 via underwater cables 142 which include power lines. An external control system may be stationed on the sea vessel 140 for powering the device 100 and communicating with the electronic unit 134 and to thereby control various functions of the device 100. The external control system may include a power source such as solar panels for powering the device 100 via the power lines. Each of the electronic unit 134 and external control system has a data communication module and the communication between the electronic unit 134 and external control system may be based on wired data transmission via the cables 142 or wireless transmission via various wireless data communication protocols. For example, in wireless data communication, the data communication module may include a wireless network interface controller. As the device 100 is at least partially underwater, a suitable wireless data communication protocol may be based on underwater acoustic communication or acoustic waves and the data communication module or wireless network interface controller may include suitable components for effecting such acoustic communication.

The device 100 or a network of devices 100 is thus communicatively coupled to the external control system, allowing the external control system to remotely control the device 100. Remote control of the device 100 allows a user located away from the device 100, such as on the sea vessel, to control various functions of the device 100. For example, the user can fill the internal chamber 104 / bladders 126 selectively between water and gas to adjust the geometrical profile of the device body 102 as well as to control buoyancy of the device 100 for ascending / descending. Remote control of the device 100 may include remotely selecting the open / closed states of the valves of the bladders 126. Moreover, instead of manual control by the user, the external control system may be programmed with suitable algorithms / logic to control various functions of the device 100 and making real-time adjustments depending on various conditions or parameters, such as current weather.

The external control system collects various types of data related with but not limited to, seasonal changes, climate patterns, weather forecasts, tides, and swells. If a network of devices 100 is implemented, the data collected by the external control system can be referred to as global data as it is applicable to all the devices 100, while the physical parameters measured by the sensors of individual devices 100 can be referred to as local data. The external control system receives the local data from the electronic unit 134 and processes it together with the global data to thereby control various functions of the device 100, such as to control filling of the internal chamber 104 / bladders 126 which adjusts the geometrical profile of the device body 102. For example, if the current tide height is known, the amount of air and water in the bladders 126 can be controlled to adjust the overall height of the device 100 so that the top of the device 100, e.g. the top of the rear end 108 of the ramp, is aligned to the water surface most of the time.

Combining global data on what has happened historically, such as climate patterns, and local data on what is happening currently, such as current weather, helps in understanding of conditions at the geographical location where the device 100 is deployed. These conditions may relate but are not limited to seasonal changes, wave directions, weather dynamics, etc. The device 100 can thus be deployed at specific orientation / arrangement and the geometrical profile of the device body 102 can be adjusted to optimize the accumulation of sediments 60. The combination of global and local data would make the device 100 more functional and adaptable to various changes in seasons and weather conditions, etc.

In some embodiments, the device 100 includes a seeding area 144 for storing aquatic seeds. The aquatic seeds include coral seeds and/or vegetation seeds. Coral seeds promote growth of corals which eventually result in forming of coral reefs. Vegetation seeds promote growth of aquatic vegetables and plants underwater. Non-limiting examples of vegetation seeds include mangrove and coconut seeds. A combination of the aquatic seeds can be dispersed or released from the seeding area 144 into the water body 50 to grow marine life such as corals, reefs, and vegetation around the desired location where sediments 60 are accumulated. Specifically, the growth of marine life growths to bind the sediments 60 together to stabilize and strengthen them as a foundation that promotes growth of geological formations 70 and more marine life.

The device 100 can also act as an artificial reef structure due to the material composition of the device body 102, such as steel and biodegradable textiles. The variation of the geometrical profile enables aquatic plants such as algae and other marine invertebrates such as barnacles and coral larvae to attach over time. The accumulation of marine life attached to the device 100 in turn provides intricate structure and food for fish assemblages. Moreover, the device 100 can be easily transported to another location by controlling its buoyancy as described above to promote accumulation of sediments 60 and growth of geological formations 70 and marine life at the new location.

In one embodiment, the seeding area 144 is a container that stores the aquatic seeds. For example, the container is a separate object that is attached to the device body 102 by fasteners such as straps, touch fasteners, or ties. Alternatively, the container is in the form of a pouch that is integrated with the material of the device body 102, such as by sewing or adhesive. The container may have time-release mechanism such that the aquatic seeds are automatically released after a predetermined time period has lapsed. The time-release mechanism may be in the form of vents in the container that automatically opens after lapsing of the time period. The aquatic seeds may be released in a single batch or in multiple batches over a period of time. Alternatively, the container may be made of a material that disintegrates, e.g. by dissolving, after being underwater for a certain amount of time and/or exposed to sunlight for a certain amount of time. Yet alternatively, the container may be made of porous bags or packets that are easily broken so that when the aquatic seeds in the container grow, they will propagate outside of the container and into the water body 50.

In another embodiment, the seeding area 144 is an area on the external surface of the device body 102. The aquatic seeds are laced onto the seeding area 144 so that once the seeding area 144 is underwater, the aquatic seeds will float away from the seeding area 144 and disperse into the water body 50.

The device 100 can thus promote growth of geological formations 70 like sandbars as well as marine life especially corals and reefs. Growth of corals helps to moderate damage to existing corals caused by increasing frequency of coral bleaching, which has a huge impact on marine life and ecosystems surrounding coral reefs. Conventional approaches that promote growth of resilient reef ecosystems include building artificial reef structures made of natural or synthetic materials such as concrete, cement, steel, or limestone, but these structures are static and likely permanently localized to a specific geographical location. The device 100, which is easily transportable and deployed at different locations, has the advantage of being adaptable for promoting growth of corals and reefs at various locations to provide stable growing habitats for marine life and other aquatic organisms.

The device 100 submerged in the water body 50, with the assistance of the electronic unit 134 and external control system to process relevant data, functions to effectively facilitate accumulation of sediments 60 at a desired location with real-time adjustment, such as of the geometrical profile of the device body 102, in response to varying conditions, such as weather changes. By using a combination global and local data, the ideal orientation / arrangement and geometrical profile can be identified and the device 100 and be moved accordingly to optimize the accumulation of sediments 60. Compared to conventional approaches like coastal dredging, the costs of the device 100 and use of a network of devices 100 in a water body 50 are significantly lower.

The device 100 can thus be used to accumulate sediments 60 that grow into geological formations 70. With sufficient time, these geological formations 70 will naturally grow to form islands and beaches, helping to preserve coastal regions which are vulnerable to coastal or soil erosion. Some other applications of the device 100 include, but are not limited to, deploying the device 100 in a wetland to mitigate soil erosion and protect the wetland, maintaining water channels and other waterways, and to maintain coral ecosystems. While many examples described above relate to the water body 50 being a natural body of water such as the sea or river, the device 100 can have applications in non-natural water bodies 50. For example, the device 100 can be used in aquariums and tanks where there is a water body 50 inside and a water current is artificially generated. Another example would be in waste water treatment facilities to facilitate accumulation of sediments 60 like sludge. Yet another example would be in the mining industry wherein water bodies 50 may be found in mines.

In the foregoing detailed description, embodiments of the present disclosure in relation to a submersible device and a method for facilitating accumulation of sediments are described with reference to the provided figures. The description of the various embodiments herein is not intended to call out or be limited only to specific or particular representations of the present disclosure, but merely to illustrate non-limiting examples of the present disclosure. The present disclosure serves to address at least one of the mentioned problems and issues associated with the prior art. Although only some embodiments of the present disclosure are disclosed herein, it will be apparent to a person having ordinary skill in the art in view of this disclosure that a variety of changes and/or modifications can be made to the disclosed embodiments without departing from the scope of the present disclosure. Therefore, the scope of the disclosure as well as the scope of the following claims is not limited to embodiments described herein.

Claims

1. A device submersible in a water body for facilitating accumulation of sediments, the device comprising:

a device body comprising an internal chamber tillable for defining a geometrical profile of the device body;

wherein the device when submerged in the water body diverts a water current in the water body flowing against the device, the diverted water current transporting sediments that accumulate around the device.

2. The device according to claim 1 , the device body further comprising a front end, a rear end, and an ascending region from the front end to the rear end.

3. The device according to claim 2, wherein the ascending region has a gradient percentage ranging from 50% to 100%.

4. The device according to any one of claims 1 to 3, wherein the device has an overall height of at least 2m.

5. The device according to any one of claims 1 to 4, wherein the device has an overall length of at least 10m.

6. The device according to any one of claims 1 to 5, further comprising a plurality of bladders disposed within the internal chamber of the device body, wherein each bladder is tillable such that the bladders collectively fill the internal chamber.

7. The device according to claim 6, further comprising a number of inlets and a number of outlets disposed on the device body for fluid communication with the bladders.

8. The device according to claim 7, wherein each bladder is tillable selectively between water and gas via the inlets and outlets to thereby adjust the geometrical profile of the device body and control buoyancy of the device.

9. The device according to claim 8, wherein the bladders are fluidically connected to each other to enable continuous fluid communication between the bladders.

10. The device according to claim 8, wherein the bladders are fluidically connected to each other via solenoid valves, each valve selectable between an open state and a closed state.

1 1. The device according to claim 10, wherein the bladders are independently tillable by selecting each valve between the open and closed states.

12. The device according to claim 1 1 , wherein each bladder comprises an inlet valve and an outlet valve configured to fill the respective bladder selectively between water and gas.

13. The device according to any one of claims 7 to 12, further comprising a water pump housed within the internal chamber and fluidically connected to an inlet for filling the bladders with water from the water body.

14. The device according to any one of claims 7 to 13, further comprising an air compressor housed within the internal chamber for discharging air to inflate the bladders.

15. The device according to any one of claims 7 to 13, wherein an inlet is connectable to an external gas pump for inflating the bladders.

16. The device according to any one of claims 1 to 15, further comprising a ballast removably attached to the device body to assist submersion of the device.

17. The device according to any one of claims 1 to 16, further comprising a frame structure removably attached to the device body for stabilizing the device in the water body.

18. The device according to any one of claims 1 to 17, further comprising one or more straps removably attached to the device body to secure the geometrical profile of the device body.

19. The device according to any one of claims 1 to 18, further comprising an electronic unit attached to the device body, the electronic unit comprising a set of sensors configured to measure physical parameters related to water body.

20. The device according to claim 19, the sensors comprising a force sensor for measuring forces exerted by the water body directly on the device.

21. The device according to claim 19 or 20, the sensors comprising a tilt sensor for measuring forces of the water current surrounding the device.

22. The device according to any one of claims 19 to 21 , the electronic unit further comprising a data communication module for communicating with an external control system.

23. The device according to claim 22, wherein the submersible device is remotely controllable by the external control system to adjust the geometrical profile of the device body and control buoyancy of the device.

24. The device according to any one of claims 1 to 23, further comprising a seeding area for storing and releasing aquatic seeds into the water body.

25. The device according to claim 24, wherein the seeding area is a container configured to automatically release the aquatic seeds after a predetermined time period has lapsed.

26. A system for facilitating accumulation of sediments, comprising:

a network of devices submersible in a water body having a water current, each submersible device comprising a device body comprising an internal chamber tillable for defining a geometrical profile of the device body; and

an external control system communicatively coupled to the network of devices for remotely controlling the submersible devices,

wherein the devices when submerged in the water body divert the water current flowing against the respective device, the diverted water current transporting sediments that accumulate around the respective device.

27. The system according to claim 26, wherein the devices are remotely controllable by the external control system to adjust the geometrical profile of the respective device body and control buoyancy of the respective device.

28. The system according to claim 27, each device further comprising a plurality of bladders disposed within the internal chamber of the device, wherein each bladder is tillable such that the bladders collectively fill the internal chamber.

29. The system according to claim 28, wherein each bladder is tillable selectively between water and gas to thereby adjust the geometrical profile of the respective device body and control buoyancy of the respective device.

30. The system according to claim 29, wherein for each device, the plurality of bladders are fluidically connected to each other via solenoid valves, each valve selectable between an open state and a closed state, and wherein each of the plurality of bladders are independently tillable by selecting each valve between the open and closed states.

31. A method for facilitating accumulation of sediments, the method comprising:

engaging a water current in a water body by a device submerged in the water body, the device comprising a device body comprising an internal chamber tillable for defining a geometrical profile of the device body;

diverting the water current by the submerged device;

transporting sediments by the diverted water current; and accumulating the sediments around the submerged device.

32. The method according to claim 31 , the method comprising submerging the device in the water body such that the water current flows against the device.

33. The method according to claim 31 or 32, wherein the device further comprises a plurality of bladders disposed within the internal chamber of the device body, the method further comprising filling each bladder selectively between water and gas to thereby adjust the geometrical profile of the device body and control buoyancy of the device.

34. The method according to claim 33, wherein the bladders are fluidically connected to each other via solenoid valves, the method further comprising selecting each valve between the open and closed states and filling each device independently of each other.

35. The method according to claim 34, wherein each bladder comprises an inlet valve and an outlet valve, the method further comprising filling, via the inlet and outlet valves, each bladder selectively between water and gas.