CA3019415A1

CA3019415A1 - Shapeshifting multi-mode personal watercraft

Info

Publication number: CA3019415A1
Application number: CA3019415A
Authority: CA
Inventors: Derek Whitaker
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-03-31
Filing date: 2017-03-31
Publication date: 2017-10-05
Also published as: US20190112006A1; CN109153435A; WO2017168169A1; EP3436341A1

Abstract

A watercraft comprising: a first section; a second section; and a connecting element joining the first section to the second section, wherein the connecting element has a first unextended state and a second extended state, and wherein the connecting element can be moved between the first and second states to alter the relative positions of the first and second sections.

Description

Shapeshifting multi-mode personal watercraft This invention relates to multi-mode personal watercraft. It also relates to a method of assembling a multi-mode personal watercraft and a kit of parts for assembly into a multi-mode personal watercraft.
Background 1.0 In the field of nautics there are several different types of watercraft, each being suited to a particular mode of operation. For example, kayaks canoes and dinghies are generally suitable for paddling, whereas yachts, catamarans and sailing dinghies are generally suitable for sailing. Further modes of operation include rowing, sculling, pedal power, stand-up paddling, outboard motor power.
However, in some applications it may be desirable to travel for a portion of a journey in a first mode, and to proceed for another portion of a journey in a second mode. In the prior art, this would be achieved through the provision of multiple different watercraft. This is both inconvenient and expensive for a user. Alternatively, a user could attempt to operate a single watercraft in two different modes. However, as prior art watercraft are suited to only one mode of operation, the watercraft would operate sub-optimally in a second mode of operation.
It is an aim of the present invention to overcome some of the drawbacks set out above. This aim is achieved by providing a single watercraft, wherein a user can alter the shape of the watercraft. This allows the craft to perform optimally in multiple modes, e.g. the shape of a craft can initially be of the form of a kayak to operate in a first mode (paddling), and the user can alter the shape of the craft from a kayak form to a catamaran form to operate in a second mode (sailing). The shape of the craft can be altered in shape for operation in further modes (sculling, stand-up paddling, outboard motor powered travel, etc).
Additionally, in the field of nautics watercraft are generally built in a workshop or docks and sold to an end user fully assembled. This has the advantage that the A

2 watercraft are ready to use immediately on purchase. However, this has the drawback that watercraft must be transported fully assembled to their intended point of use. This can be inconvenient for a user as fully assembled watercraft are relatively large and bulky. For example, they cannot be carried by a user as hand luggage on an aeroplane, but must be shipped separately. This can be expensive and time-consuming.
It is a further aim of the present invention to overcome some of the drawbacks set out above. This aim is achieved by providing a watercraft that is modular, i.e. the watercraft comprises discrete modules that can be readily assembled by an end user into a functioning watercraft. By providing the watercraft as a plurality of modules, the watercraft can be stowed in a compact form when not in use. For example, each of the modules can fit into a backpack which is portable (i.e. it can be readily carried by an average able-bodied person) and can be carried on an aeroplane as hand luggage. As an example, a backpack of dimensions 52cm by 35cm by 22cm, and weight 5-10kg could be described as being portable. However, a backpack containing a watercraft according to the present invention is preferably no heavier than 6kg in a basic mode (e.g. for paddling), and no more than 14kg with other varying modes of operation (e.g. including a sailing rig). In both of these cases, the dimensions would still comply with maximum backpack dimensions.
Summary of the invention In accordance with a first aspect of the present invention there is provided a watercraft comprising:
a first section;
a second section; and a connecting element joining the first section to the second section, wherein the connecting element has a first unextended state and a second extended state, and wherein the connecting element can be moved between the first and second states to alter the relative positions of the first and second sections.

=

3 The first and second sections could respectively comprise first and second floats.
The first and second floats could be inflatable, or formed of a rigid material. Where they are formed of a rigid material first and second floats could be hollow or solid.
The connecting element could comprise an inflatable cross-strut. The connecting element could comprise a telescopic cross-strut. The connecting element could comprise a hinged cross-strut.
The hinged cross-strut could be connected to a rotatable or moveable pole which is operable by a user aboard the watercraft to move the hinged cross-strut between the first and second states to alter the relative positions of the first and second sections.
In accordance with a second aspect of the present invention there is provided a watercraft comprising a plurality of discrete modules, wherein each of the modules comprise complementary parts of a releasable attachment means.
One of the modules could be a float. One of the modules could be a cross-strut.
The cross-strut could have a first unextended state and a second extended state, and the cross-strut could be moveable between the first and second states.
The releasable attachment means could comprise a zip fastener.
In accordance with a third aspect of the present invention there is provided a kit of parts comprising:
first and second floats; and a cross-strut, wherein each end of the cross-strut comprises a first part of a releasable attachment means, and wherein each of the floats comprise complementary second parts of a releasable attachment means.
The first and second floats could be inflatable, or formed of a rigid material. Where they are formed of a rigid material first and second floats could be hollow or solid.

4 The connecting element could comprise an inflatable cross-strut. The connecting element could comprise a telescopic cross-strut. The connecting element could comprise a hinged cross-strut.
The releasable attachment means could comprise a zip fastener.
In accordance with a fourth aspect of the present invention there is provided a method of assembling a watercraft, the method comprising the steps of:
io providing first and second floats;
providing a cross-strut, wherein each end of the cross-strut comprises a first part of a releasable attachment means, and wherein each of the floats comprise complementary second parts of a releasable attachment means;
connecting the first part of the releasable attachment means of the cross-strut to the second part of the releasable attachment means of the first float; and connecting the first part of the releasable attachment means of the cross-strut to the second part of the releasable attachment means of the second float.
In accordance with a fourth aspect of the present invention there is provided a method of changing the shape of a watercraft, the watercraft comprising:
a first section;
a second section; and a connecting element joining the first section to the second section, wherein the connecting element has a first unextended state and a second extended state, the method comprising the step of:
moving the connecting element between the first and second states to alter the relative positions of the first and second sections Detailed description The invention will now be described with reference to the accompanying drawings, in which:

5 Fig. 1 schematically shows a watercraft in accordance with an embodiment of the present invention; and Fig. 2 schematically shows sectional and partial views of some of the components of Fig. 1;
3.0 Fig. 3 schematically shows the watercraft of Fig. 1, showing additional details;
Fig. 4 schematically shows a load dispersant frame assembly for use with the watercraft of Fig. 3;
Fig. 5a schematically shows a cross section of the float of Fig. 3 to show item 8 in more detail;
Fig. 5b schematically shows a cross section of the float of Fig. 3, to show item 14 in more detail;
Fig. 6 schematically shows a watercraft in accordance with an embodiment of the invention being operated in a first mode (left hand side) and a second mode (right hand side);
zo Fig. 7 schematically shows three examples of extendable cross-struts suitable for use in the present invention;
Fig. 8 schematically shows a plan view of a watercraft in accordance with an embodiment of the invention;
Fig. 9 schematically shows a plan view of a watercraft in accordance with a further embodiment of the invention;
Fig. 10 schematically shows a modular paddle for use with the present invention;
and Fig. 11 schematically shows a rotatable seat for use with the present invention.
Fig. 1 shows a schematic illustration of a watercraft in accordance with an embodiment of the present invention. The watercraft comprises a pair of floats which are elongate and extend substantially parallel to one another. The floats 2 are connected together by a first cross-strut 3 and a second cross-strut 4. The floats 2 shown are made of a polymer material (for example polyester) and are inflatable.

6 The floats 2 may be inflated via a valve 9. However, in other embodiments rigid hollow floats may be used, or completely solid floats. The floats may also have pressure release valve (not shown) to relieve pressure and prevent explosion, e.g. in strong sunlight or due to overinflation.
In Fig. 1 a fully assembled watercraft is shown. However, the floats 2, the first cross-strut 3 and the second cross-strut 4 comprise discrete separate modules that can be joined to each other by an end user. This can be seen more clearly in Fig. 2.
Fig. 2 schematically shows sectional and partial views of some of the components of Fig. 1. The upper part of Fig. 2 shows a cross-sectional view of the attachment point between one of the floats 2 and the cross-strut 3. The float 2 comprises a first half 5 of an attachment means, and the cross-strut 3 comprises a complementary second half 6 of an attachment means. The first and second halves 5, 6 of the releasable attachment means are configured to engage with one another to secure the cross-strut 3 and the float 2 together. In the embodiment of Fig. 2, the first half 5 of the attachment means comprises a first half of a toothed zip connector, and the second half 6 of the attachment means comprises a corresponding second half of a toothed zip connector. However, alternative attachment means could also be used, for example, hook and loop fasteners, latches, straps, hasps, chains or any other suitable attachment means. The attachment means could removably or permanently attach the cross-strut to the floats.
The lower part of Fig. 2 shows a plan view of the attachment point between one of the floats 2 and the cross-strut 3. An air channel 7 is provided between the float 2 and the cross-strut 3. This allows air to flow between the float 2 and the cross-strut 3, and so a single inflation point can be provided on the watercraft rather than respective inflation points for each component. A blocking means 8, in the form of a releasable clip, is provided on the air channel 7, so that the interiors of the float 2 and the cross-strut 3 can be isolated from each other once inflated. This can be useful in ensuring that the entire vessel does not deflate if a puncture occurs in one of the float 2 and the cross-strut 3.

7 Fig. 3 schematically shows the watercraft of Fig. 1, showing additional details. In Fig. 3 a pair of floats 1 are connected together by a first cross-strut 2 and a second cross-strut 17. The first cross-strut 2 is connected to the floats 1 by a pair of circumferential zips (one of which can be seen, indicated as item 7). The cross-strut 2 is inflatable via a valve 6 and contains an expandable section 36. One of the floats has a mounting point 14, which is secured into float 1 via an integral flange 13 (this will be described in more detail in Fig. 5b).
Each float has a tapered front end 3 (only one indicated) that allows impact 3.0 absorption. The floats carry a plurality of retaining means 15 for attaching a load dispersant frame assembly to the watercraft. In Fig. 3 a simple strap and buckle is shown for retaining means 15, but any suitable retaining means could be used in practice. Fig. 3 shows only a single retaining means 15, but in practice more than one retaining means would generally be used.
The floats each comprise an inner skin and an outer skin. The outer skin is formed of a material that stretches less than the inner material. The inner material may be formed of a hard wearing laminate, for example a polyurethane coated polymer textile (such as nylon) to prevent chafing between the inner and outer skins.
The outer material may be formed of polyester to prevent salt water resistance and minimal stretch. The inner skin is generally welded together to provide an airtight enclosure. The outer skin is generally stitched. Alternatively, the floats can be of a single airtight material, e.g. HypeIon (RTM) or polyvinylchloride (PVC).
A zip 12 in the outer skin provides access to the inner skin of the float.
This allows a user to remove or replace the inner skin.
Item 35 indicates a removable safety chamber. The safety chamber is inflatable and provides additional or redundant buoyancy. This can prevent the watercraft from sinking if a float or cross-strut is punctured. The safety chamber also prevents the watercraft from rotating or overturning if a float or cross-strut is punctured. The safety chamber 35 in Fig. 3 is attached to the float with a zip, although any attachment means could be used in practice. Said safety chamber can be retracted behind a panel for deployment as required.

8 Item 8 is a rigid panel that acts to maintain the cross-sectional shape of the float 3.
In Fig. 3 the rigid panel is attached retained on the end of the float 3 by a sphincter 9.
However, the rigid panel 8 could also be attached to float 3 by being trapped between the inner skin and the outer skin. Alternatively, the rigid panel 8 could be attached by a separate attachment means (e.g. a releasable clip).
Items 5 and 11 in Fig. 3 correspond to items 7 and 8 in Fig. 2.
Fig. 4 schematically shows a load dispersant frame assembly for use with the watercraft of Fig. 3. The frame comprises longitudinal members, which lie in the direction of the length of the watercraft, and transverse members 51, 52, which lie at right angles to the longitudinal members, as shown. Corner pieces connect the longitudinal members to the transverse members 51, 52.
The transverse members 51, 52 are extendable to accommodate the expansion of the watercraft in the transverse direction. The transverse members may either include expansion pieces to extend their length, or they may be telescopic.
zo The centre longitudinal member carries attachment means for a bench 56 upon which a user may sit in use. The bench 56 may be a rigid piece, or may be formed of a flexible material or a mesh. The foremost transverse member carries a mast foot bracket 55 for a mast foot assembly. A mast foot bracket support (or supports) 57 runs between the mast foot bracket 55 and the transverse member 51, or to a suitable position on the frame or the floats. The mast foot bracket support 57 prevents fore and aft movement of the mast foot bracket 55 (and hence the mast).
The rearmost transverse member 52 carries a mounting point for a rudder post 53, which may carry a rudder 54.
Fig. 5a schematically shows a cross section of the float of Fig. 3 to show item 8 in more detail. A rigid panel 10 is held in the end of a float 1 by a sphincter 16.
Fig. 5b schematically shows a cross section of the float of Fig. 3, to show item 14 in more detail. The mounting point 14 is firmly maintained in a position by rigid flange

9 20. Fig. 5b depicts the mounting point in a substantially vertical position, however said position could be at any angle about the circumference to provide a mounting point for components as required. The flange 20 comprises an arched section 18 which is shaped to conform to the shape of the outer skin of the float 21 when it is fully inflated, such that the skin of the float forms a smooth continuous circle which includes the arched section 18. The arched section is connected to the outer skin of the float by attachment means 19 in the embodiment shown in Fig. 5b. However, alternatively the arched section 18 could be formed integrally with the outer skin of the float, e.g. it could be made of a rigid plastics material which is moulded into the 3.0 flexible plastics material of the float skin. Alternatively, the arched section 18 could be trapped between the inner skin and outer skin of the float to hold it in place.
Fig. 6 schematically shows a watercraft in accordance with an embodiment of the invention being operated in a first mode (left hand side) and a second mode (right hand side).
On the left hand side of Fig. 6 the watercraft (which comprises a pair of floats 2 connected by an extendable cross strut 3) is shown in a first configuration having a first shape. The shape of the first configuration is a kayak shape. In this configuration, the cross strut 3 is unextended, and so the floats 2 are in close proximity to one another, giving the watercraft a relatively narrow shape.
This shape makes the watercraft suitable for paddling, and the user can be seen operating the watercraft using a paddle 4.
On the right hand side Fig. 6 the watercraft is shown in a second configuration having a second shape. The shape of the second configuration is a catamaran shape. In this configuration, the cross strut 3 is extended, and so the floats 2 are distant from one another, giving the watercraft a relatively wide shape. This shape makes the watercraft suitable for sailing, and the user can be seen operating the watercraft using a sail 5. In addition, the wider shape offers increased resistance to capsize or overturn especially while sailing.

Fig. 7 schematically shows three examples of extendable cross-struts suitable for use in the present invention. The three examples are shown on the left hand side in an unextended state and on the right hand side in an extended state.
5 The top example shows an inflatable cross-strut 3. The cross-strut 3 comprises an expansion sleeve 7 which is contained within the cross-strut 3 in its unextended state. The expansion sleeve is prevented from extending the length of the cross-strut 3 due to a circumferential zip, which is the closed configuration in the unextended state of the cross-strut. A reinforcing pole 10 runs through the cross-

10 strut 3 to give it extra rigidity, and this can slide in a recess (shown in dotted lines) as the cross-strut 3 extends. However, in some applications the reinforcing pole can be omitted entirely.
To move the cross-strut from the unextended state to the extended state, the circumferential zip is unzipped into the open configuration. The expansion sleeve 7 fills with air from the interior of the cross-strut 3 and the sections of the cross-strut 3 are moved away from one another by the expansion of the expansion sleeve 7.
This has the effect of moving the floats 2, to which the ends of the cross-strut 3 are connected, away from one another.
While the above mechanism has been described with reference to a cross-strut, it could also be applied to a float of the watercraft in order to extend the length of the watercraft.
The middle example shows a telescopic cross-strut 3. The cross-strut 3 comprises a pair of poles, wherein one of the poles is received within the other pole.
On the left hand side the cross-strut 3 is shown in an unextended state, wherein one pole is completely received inside the other pole. The poles can be retained in this state via securing means (not shown), for example a projection on one pole can be received in a recess in a surface of the other pole, or the poles can be locked, chained or tied together, or secured with any other suitable means.

11 To move the cross-strut from the unextended state to the extended state, the user disengages the securing means to allow relative movement between the poles.
With the securing means released, the user can then pull one pole out of the other pole to move the floats away from one another. Once the cross-strut 3 is fully extended the securing means can be re-engaged to retain the poles at their relative positions.
Alternatively, a second securing means can be used to retain the poles at their relative positions.
The bottom example shows a cross-strut 3 comprising a pair of hinged poles.
On the left hand side the cross-strut 3 is shown in an unextended state, wherein the hinges poles are secured with an acute angle between the poles. The poles can be retained in this state via securing means (not shown), for example a locking pin can be passed through an aperture in the hinge to prevent angular rotation of the poles, or the poles can be locked, chained or tied together, or secured with any other suitable means.
To move the cross-strut from the unextended state to the extended state, the user disengages the securing means to allow relative angular movement between the zo poles. With the securing means released, the user can then increase the angle between the poles to move the floats away from one another. Once the cross-strut 3 is fully extended the securing means can be re-engaged to retain the poles at their relative angular positions. Alternatively, a second securing means can be used to retain the poles at their relative angular positions. Intermeshing gears or toothed cogs can be used to maintain symmetrical angular movement between the poles.
Fig. 8 schematically shows a plan view of a watercraft in accordance with an embodiment of the invention. The watercraft comprises a pair of floats 2 connected by two cross-struts 3. The cross-struts 3 are of the hinged type described with respect to Fig. 7. A rotatable pole runs down the central axis of the watercraft. In use, a user sits on a bench 11 connecting the two floats. The bench 11 is made of a flexible material to accommodate relative movement of the floats 2.

12 The hinges of the cross-struts 3 are threaded on the ends of the rotatable pole.
Rotation of the pole acts to move central portion of the hinges towards or away from one another, and so control the relative angular position of the hinged cross-struts 3.
The left hand side of Fig. 8 shows the cross-struts 3 in their unextended states, putting the watercraft in a kayak form for paddling. The right hand side of Fig. 8 shows the cross-struts 3 moved to their respective extended states, putting the watercraft in the catamaran form for sailing. The rotation pole has a rotation handle that can be manipulated by a user sat on bench 11 as shown. This allows a user to alter the shape of the watercraft, even when it is in use, i.e. on the water.
3.0 While the above example has been described with a threaded pole and the two hinged cross-struts moving towards one another when moving to their unextended states, it would also be possible to link the hinged cross-struts together with an unthreaded pole attached to each hinge. In this case, the pole could simply be moved along the length of the watercraft by a user, and the hinged cross-struts would move in the same direction as the pole is moved to put them into their extended or unextended states. The hinges could be locked in their extended or unextended states, e.g. by passing a locking pin through each hinge. This arrangement is shown in Fig. 9.
Fig. 9 schematically shows a plan view of a watercraft in accordance with a further embodiment of the invention. In Fig. 9 the watercraft comprises a pair of floats 71 connected by telescopic cross-struts 72. The floats 71 are also connected by a pair of hinged cross-struts 81, hinged at respective points 75 and 77. The hinge points 75, 77 form receptacles for a rudder post 76 and a mast 78 bearing a sail 79.
The hinge points 75, 77 are connected to one another by a longitudinal connecting member 73, which is moveable fore and aft as indicated by arrows 74.
.. Item 80 is a flexible component, such as a webbing strap. A user can transfer their weight to the strap, which acts to draw the floats towards one another, and so enables the telescopic members 72 to move with less friction than if a user sat on the telescopic members 72 directly.

13 Extension and retraction of the cross-struts is effected by a user moving the longitudinal connecting member either fore or aft. Alternatively, extension of the cross-struts can be effected by a user sitting on one of the two floats and pushing against the other float with their feet.
Fig. 10 schematically shows a modular paddle for use with the present invention.
The paddle comprises a pair of paddle shaft sections 40 and a pair of paddle blades 41. The modularity of the paddle allows these component parts to be used as multiple components of a watercraft as shown in the lower section of Fig. 9.
3.0 For example, the paddle blade 41 can be used as a rudder of the watercraft as indicated at reference numeral 47. A paddle shaft section 40 can be used as a tiller of the watercraft as indicated at reference numeral 46. A bracket 49 on a rear part of the watercraft is used to locate the rudder (paddle blade 41) and allow it to rotate.
The paddle is removably received in the bracket 49, and it can be removed for use in paddling.
A paddle blade 41 and paddle shaft section 40 together can be used as a keel or centre board of the watercraft as indicated at reference numeral 44. A bracket 45 is zo attached to a seat frame of the watercraft, to which the paddle shaft section 40 can be attached. The bracket 45 allows the keel assembly (combined paddle blade 41 and paddle shaft section 40) to rotate both fore and aft.
A mast foot bracket 43 is attached to the watercraft as previously described.
A mast pole 42 bearing a sail S is located in mast foot bracket 43, which allows the mast pole 42 to rotate. The mast pole 42 may be telescopic or segmented to allow a variety of lengths of the mast pole 42.
Fig. 11 schematically shows a rotatable seat for use with the present invention. The seat is particularly useful for angling / fishing from a watercraft.
Fig. 11 shows a watercraft comprising a pair of floats 63 connected by a pair of cross-struts 62 having a platform therebetween. The rotatable seat comprises a rotatable base section 61 which is rotatably mounted on a central mounting point on

14 the platform and can rotate in the directions indicated by arrows 68. A
locking mechanism 65 is provided within reach of the seat user which is operable to brake rotation of the rotatable base 61 and lock it in place. The rotatable base section 61 has a backrest 64. A footrest 66 is also attached to the rotatable base section 61, and a rod holder, e.g. for a fishing rod, is attached to the footrest 66.
Alternative arrangements io The invention is not limited to the specific embodiments disclosed above, and other possibilities will be apparent to those skilled in the art. For example,

Claims

1. A watercraft comprising:
a first section;
a second section; and a connecting element joining the first section to the second section, wherein the connecting element has a first unextended state and a second extended state, and wherein the connecting element can be moved between the first and second states to alter the relative positions of the first and second sections.

2. A watercraft according to claim 1, wherein the first and second sections respectively comprise first and second floats.

3. A watercraft according to claim 2, wherein the first and second floats are inflatable.

4. A watercraft according to claim 2, wherein the first and second floats are formed of a rigid material.

5. A watercraft according to claim 4, wherein the first and second floats are hollow.

6. A watercraft according to claim 4, wherein the first and second floats are solid.

7. A watercraft according to any preceding claim, wherein the connecting element comprises an inflatable cross-strut.

8. A watercraft according to any of claims 1 to 6, wherein the connecting element comprises a telescopic cross-strut.

9. A watercraft according to any of claims 1 to 6, wherein the connecting element comprises a hinged cross-strut.

10. A watercraft according to claim 9, wherein the hinged cross-strut is connected to a rotatable pole which is operable by a user aboard the watercraft to move the hinged cross-strut between the first and second states to alter the relative positions of the first and second sections.

11. A watercraft comprising a plurality of discrete modules, wherein each of the modules comprise complementary parts of a releasable attachment means.

12. A watercraft according to claim 11, wherein one of the modules is a float.

13. A watercraft according to claim 11 or claim 12, wherein one of the modules is a cross-strut.

14. A watercraft according to claim 13, wherein the cross-strut has a first unextended state and a second extended state, and wherein the cross-strut can be moved between the first and second states.

15. A watercraft according to any of claims 11 to 14, wherein the releasable attachment means comprises a zip fastener.

16. A kit of parts comprising:
first and second floats; and a cross-strut, wherein each end of the cross-strut comprises a first part of a releasable attachment means, and wherein each of the floats comprise complementary second parts of a releasable attachment means.

17. A kit of parts according to claim 16, wherein the first and second floats are inflatable.

18. A kit of parts according to claim 16, wherein the first and second floats are formed of a rigid material.

19. A kit of parts according to claim 18, wherein the first and second floats are hollow.

20. A kit of parts according to claim 18, wherein the first and second floats are solid.

21. A kit of parts according to any of claims 16 to 20, wherein the cross-strut comprises an inflatable cross-strut.

22. A kit of parts according to any of claims 16 to 20, wherein the cross-strut comprises a telescopic cross-strut.

23. A kit of parts according to any of claims 16 to 20, wherein the cross strut comprises a hinged cross-strut.

24. A kit of parts according to and of claims 16 to 23, wherein the releasable attachment means comprises a zip fastener.

25. A method of assembling a watercraft, the method comprising the steps of:
providing first and second floats;
providing a cross-strut, wherein each end of the cross-strut comprises a first part of a releasable attachment means, and wherein each of the floats comprise complementary second parts of a releasable attachment means;
connecting the first part of the releasable attachment means of the cross-strut to the second part of the releasable attachment means of the first float; and connecting the first part of the releasable attachment means of the cross-strut to the second part of the releasable attachment means of the second float.

26. A method of changing the shape of a watercraft, the watercraft comprising:
a first section;
a second section; and a connecting element joining the first section to the second section, wherein the connecting element has a first unextended state and a second extended state, the method comprising the step of:
moving the connecting element between the first and second states to alter the relative positions of the first and second sections