GB2611287A

GB2611287A - Hand-powered watercraft

Info

Publication number: GB2611287A
Application number: GB2113508.2A
Authority: GB
Inventors: Macfarlane Stephen
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-09-22
Filing date: 2021-09-22
Publication date: 2023-04-05

Abstract

A hand-powered watercraft (100, Fig 1) comprising: a hull, a blade (113, Fig 1), and a blade control assembly. The blade is positioned closer to a stern of the watercraft than a bow and the blade is movable relative to the hull between a retracted position and a deployed position, The blade control assembly comprises a foot-operable retraction actuator 114, a blade-retraction mechanism, and control lines 116 and 119. The blade-retraction mechanism is actuatable by the retraction actuator via the control lines to move the blade between the retracted position and the deployed position.

Description

HAND-POWERED WATERCRAFT

Technical Field

The present disclosure relates to blades for hand-powered watercraft, and particularly, but not exclusively, blades for kayaks.

Background

Hand-powered watercraft such as sea-kayaks often have blades to stabilise the direction of travel in currents, waves and/or windy conditions. A skeg is a blade that may be deployed, adjusted and retracted up and down or may be permanently deployed, but does not rotate. It is used to counter different wind angles and strengths on a sea-kayak and is located towards the stern of the sea-kayak. A rudder is a blade that may be deployed, adjusted and retracted or may be permanently deployed. A rudder also rotates left to right to provide steering on a sea-kayak and is located towards the stern of the sea-kayak. It is also possible to have a joint rudder-skeg which is a blade that can be used as either a skeg or a rudder, depending upon how it is deployed.

Summary

There is provided a hand-powered watercraft comprising: a hull, a blade movable relative to the hull between a retracted position and a deployed position, and a blade control assembly, the control assembly comprising a foot-operable retraction actuator, a blade-retraction mechanism, and control lines, the blade-retraction mechanism being actuatable by the retraction actuator via the control lines to move the blade between the retracted position and the deployed position.

In this way, it is possible to retract and/or adjust the rudder/skeg using the feet, thereby allowing the user to keep both hands on their paddle. One of the fundamentals of Sea-kayaking is that the paddle is held with both hands. It is important to have a good hold of the paddle in all situations as it is essential for propulsion, stability and recovery. The more dynamic the situation (wind and waves) the more important it is to keep both hands on the paddle, so the sea-kayak can be controlled in respect of direction, speed and stability.

The blade may be closer to a stern of the watercraft than a bow. The blade may be positioned between a cockpit region of the watercraft and the stern of the watercraft. The blade may be located at an aft section of the watercraft, closer to the stern than the bow. The blade may be a skeg and/or a rudder. Use of a blade at the stern end of the watercraft allows a user to efficiently control the watercraft with reduced turbulence and greater control. Deployment or partial deployment of the blade at this position allows the user to prevent the stern from being blown downwind to rotate the watercraft (known as weathercocking) when paddling in a direction other than directly into the wind.

The blade may have a foil shaped cross-section. This is advantageous as this shape gives increased control in turning and reducing stalling during turning of the watercraft.

The foil shape of the rudder may be balanced. A balanced foil has the same pressure forward of the fulcrum (also known as the pivot point) as the pressure behind the fulcrum, so there is little to no resistance to turning the rudder -it is balanced. A balanced foil shape provides 'lift' in the direction of the turn, in the same way an aeroplane wing provides upwards lift, and this lift pulls the stern in the required direction. The steering fulcrum of the rudder may be positioned at 30% of the distance from a front surface of the rudder to a back of the rudder.

The blade may be a laterally central blade. Laterally central in this application means that the blade is located equidistant from the port and starboard sides of the watercraft.

In this application, port is used interchangeably with left and starboard is used interchangeably with right. Front, fore and bow are used interchangeably and back, rear, aft and stern are also used interchangeably.

At least part of the rudder may be laterally movable relative to the hull. The rudder may be laterally movable relative to the hull when the rudder is in the deployed position. In this way, the blade may be a skeg and a rudder. The blade acts as a skeg when it is between the retracted and deployed positions and as a rudder when in the deployed position.

The blade control assembly may further comprise a foot-operable steering actuator, the rudder being actuatable by the steering actuator to laterally move the rudder relative to the hull. The rudder may be laterally movable by rotating about a laterally central steering pivot point. At least part of the rudder may be laterally movable relative to the hull. The term laterally movable in this application means movable towards the port and starboard sides of the watercraft.

The foot-operable retraction actuator may comprise a slider connected to the control lines. The foot-operable steering actuator may comprise a left pedal and a right pedal. The foot-operable retraction actuator and/or the foot-operable steering actuator may be provided on a foot control module. The foot control module may be mounted on an inner wall of the hull.

The foot-operable retraction actuator may comprise a slider connected to the control lines.

The blade may be rotationally movable between the retracted and deployed position.

When the blade is in the retracted position, it may be in a sleeve in the hull of the watercraft. When the blade is in the deployed position, it may extend beneath the hull of the watercraft.

The watercraft may further comprise a deck. The control lines may be entirely inside of a shell of the watercraft formed by the deck and the hull. The control lines may pass through a wall of a cockpit of the kayak via respective gaskets into a sealed section of the kayak. Having the control lines pass through sealed sections of the kayak away from user interaction keeps these portions of the control lines safe from damage by catching on the user or equipment.

The control lines may comprise a retraction line and a deployment line. The retraction line is configured to be pulled by the retraction actuator to cause the blade-retraction mechanism to move the blade towards the retracted position. The deployment line is configured to be pulled by the retraction actuator to cause the blade-retraction mechanism to move the blade towards the deployed position. The retraction and deployment lines act together as a two-way positive pull system, so that both lines are always under tension. This reduces occurrences of kinking or catching of the lines.

The retraction and deployment lines may be connected to each other at the blade retraction 10 mechanism.

The blade retraction mechanism may comprise a pulley wheel and the retraction and deployment lines may be connected to each other around the pulley wheel. The pulley wheel may be connected to the blade. The pulley wheel may be connected to the blade at a retraction pivot point of the blade, such that rotation of the pulley wheel causes the blade to pivot about the retraction pivot point. The blade retraction mechanism may further comprise a cog system and the pulley wheel may be connected to the blade via the cog system. The cog system may comprise a first cog, axially connected to the pulley wheel and a second cog, axially connected to the blade at the retraction pivot point, the first and second cogs being operably connected by a belt.

The control lines may further comprise a port steer line and a starboard steer line. The steer lines being operable by the foot-operable steering actuator to laterally move the rudder. The port steer line is configured to be pulled by the steering actuator to cause the rudder to move towards a first one of the port and starboard sides of the watercraft. The starboard steer line is configured to be pulled by the steering actuator to cause the rudder to move towards a second one of the port and starboard sides of the watercraft. The port and starboard steer lines act together as a two-way positive pull system, so that both lines are always under tension. This reduces occurrences of kinking or catching of the lines. The steer lines may be switchable between standard steering and reverse steering configurations, wherein in the standard configuration, the first side is the port side of the watercraft and the second side is the starboard side and in the reverse configuration the first side is the

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starboard side of the watercraft and the second side is the port side. In this way, the water craft can be adapted to user preferences on steering configuration.

The port and starboard lines may be connected via a rudder steering mechanism. The 5 retraction and deployment control lines may pass through the fulcrum of the rudder. This enables the retraction and deployment lines to remain the same length while the rudder is steered. The steering and retraction pivot points may have the same location.

The foot control module may be mounted on a fore-aft lockable sliding mechanism. This allows adjustment of the position of the foot control module according to the leg length or preference of a user. The foot control module may be mounted on an inner wall of the hull in a cockpit section of the watercraft.

The control lines may be attached to the foot control module by a pulley system configured to allow the fore-aft movement of the foot control module while retaining the control lines under tension. Each control line may have a fore-end fixed to a respective control line fixing point inside the hull. Each control line may pass through a plurality of rings of the foot control module, the rings being operable by the user via the foot control module to change the length of the path of the control lines from the fixing points, through the rings. The control lines may be parallel to one another and to a fore-aft axis of the watercraft, except for their path through the rings of the foot control module. By fixing the control lines to the fixing points in the hull and using the rings to manipulate the path of the control lines, the foot control module may be moved relative to the control line fixing points so as to act on a different section of the control lines, but the action of the foot control module to pull the control lines to operate the blade retraction mechanism and optionally the steering mechanism remains the same.

The fixing point(s) for the steering lines may be laterally central on the watercraft. The port steering line may pass from its fixing point to a middle port ring on the steering actuator, then to a wide port ring on the steering actuator and then to the steering mechanism. The starboard steering line may pass from its fixing point to a middle starboard ring on the steering actuator, then to a wide starboard ring on the steering actuator and then to the steering mechanism. The middle rings are closer to the lateral centre of the watercraft than the wide rings.

The path of the retraction and deployment control lines through the rings may provide a gearing system, such that movement of the retraction actuator may cause a smaller movement by the retraction and deployment control lines. In this way, the foot-operable retraction actuator may require a relatively larger movement which may be easier for a user to perform.

The rings may comprise a retraction floating ring, through which the retraction control line passes and through which an operation line of the foot control module also passes, the operation line being attached to the retraction actuator. The retraction control line may pass through a first fixed retraction ring on the foot control module, through the floating retraction ring and then through a second fixed retraction ring on the foot control module.

In this way, movement of the retraction actuator causes the operation line to move the retraction ring and thereby change the length of the path through the foot control module of the retraction control line. The rings may further comprise a deployment floating ring, through which the deployment control line passes and through which the operation line of the foot control module also passes, the operation line being attached to the retraction actuator. The deployment control line may pass through a first fixed deployment ring on the foot control module, through the floating deployment ring and then through a second fixed deployment ring on the foot control module. In this way, movement of the retraction actuator causes the operation line to move the deployment ring and thereby change the length of the path through the foot control module of the deployment control line.

The watercraft may comprise a plurality of sections, the sections being releasably joinable to neighbouring sections at joints. At each of the joints, each of the control lines may pass through a respective first gasket at on a first section and a respective second gasket on a second section, the first and second gaskets being configured to meet one another when the first and second sections are joined.

The watercraft may further comprise conduits surrounding a portion of each of the control lines. The conduits may surround the control lines as the control lines pass through watertight sections of the watercraft. The conduits may each surround a respective control line between two walls of a section of the watercraft. The control lines may each pass through a respective gasket in each of the walls, the conduit and gaskets providing a sealed passage through the section for the control line.

Each control line may be housed in a respective continuous sleeve. The sleeve(s) may be PTFE sleeves. The sleeves may be insertable into the conduits when the sections of the watercraft are joined. The sleeves may be sealed against the conduit at the blade end, for example, by a section of sleeve having a wider outer diameter. In this way, no water can enter the internal spaces of either between the seat and cockpit mould, or the rear section, or the tail section.

The control lines may be releasably connectable at the foot control module. In this way, the control lines in the sleeves can be inserted through the conduits from rear of the watercraft to the foot control module and then connected. When disassembling the watercraft, the control lines can be disconnected at the foot control module, the sleeves can be removed from the rear of the conduits and then the sections can be released from their joined configuration.

The blade-retraction mechanism may further comprise a rounded tapered retraction guide. In this way, in the event of catching weeds, rocks or other obstructions, the blade will centre itself and retract inside the kayak.

The watercraft may comprise a monocoque. The monocoque may comprise at least part of the deck and at least part of the hull. The watercraft may comprise a composite, such as carbon fibre, fibreglass, kevlar, aramids and/or organic materials and/or a plastic. Carbon fibre may comprise pre-impregnated (Prepreg) carbon fibre. The Prepreg may comprise epoxy resin.

The hand-powered watercraft may be a kayak, a sea kayak, a row boat, surf-ski, or any other type of hand-powered watercraft. A hand-powered watercraft is any watercraft that is primarily propelled by a user's hands via, for example, an oar or paddle. In this application, hand-powered watercraft includes a watercraft primarily propelled by hand, for example a kayak or row boat, with an auxiliary propulsion means, for example a temporary sail.

There is further provided a method of manufacture of a watercraft as described above, the method comprising: forming the hull forming the blade, forming the blade control assembly the control assembly comprising a foot-operable retraction actuator, a blade-retraction mechanism, and control lines, the blade-retraction mechanism being actuatable by the retraction actuator via the control lines to move the blade between the retracted position and the deployed position, assembling the blade control assembly in the hull, and attaching the blade to the hull, such that it is movable by the blade-retraction mechanism relative to the hull between the retracted position and the deployed position.

The method may further comprise forming the deck. Forming the deck and hull may comprise forming a plurality of sections, the sections each comprising a part of the deck and a part of the hull. Forming the deck and hull may comprise forming one or more monocoques. Forming the deck and hull and/or blade and/or blade control assembly may comprise 3D printing or rotomolding. Forming the blade and/or blade control assembly may comprise using aluminium, steel, wood or other materials.

There is further provided a computer-readable medium having computer-executable instructions adapted to cause a 3D printer to print a watercraft as described above.

The methods and devices described above may be combined in any possible combination.

The optional features described above are equally applicable to all of the described methods and devices and are not limited to the particular method/device with which they are described here.

Further features and advantages of the aspects of the present disclosure will become apparent from the claims and the following description.

Brief Description of Drawings

Embodiments of the present disclosure will now be described by way of example only, with reference to the following diagrams, in which:-Fig. 1 shows a perspective view of a sea-kayak; Fig. 2A shows a stern section of the sea-kayak of Fig. 1 with a blade in a retracted position; Figs. 2B and 2C show the stern section of Fig. 2A with the blade between the retracted position and a deployed position; Fig. 2D shows the stern of Fig. 2A with the blade in the deployed position; Fig. 2E shows the stern of Fig. 2A with the blade in the deployed position and the blade rotated to the starboard side; Fig. 3 shows a perspective, cut-away, stern-side view of a cockpit section of the sea-kayak of Fig. 1, showing a foot control module; Fig. 4 shows a perspective bow-side view of the foot control module of Fig. 3; Fig. 5 shows a sectional view of the stern section of Fig. 2A; Fig. 6 shows a perspective view of a blade retraction mechanism; Fig. 7 shows a sectional view of the blade retraction mechanism of Fig. 6 in the stern section of Fig. 5; Fig. 8 shows a perspective, cut-away view of a section of the sea-kayak of Fig. 1; Fig. 9 shows internal components of a section of the sea-kayak of Fig. 1.

Detailed Description

Fig. 1 shows a multi-sectional sea-kayak 100 having five sections 101-105. The sections include a stern section 101, a rear deck section 102, a cockpit section 103, a fore deck section 104 and a bow section 105. The sea-kayak includes a hull and a deck, seat 106, hatches 107 to 112 and blade 113.

Figs. 2A to 2E show the stern section 101 and blade 113. The blade 113 is movable relative to the hull between a retracted position shown in Fig 2A and a deployed position shown in Figs. 2D and 2E. Intermediate positions of the blade 113 between the retracted position and the deployed position are shown in Fig. 2B and Fig. 2C.

The blade 113 is laterally central on the kayak 100 Alternatively, in other embodiments, the blade may be laterally offset by being closer to one side of the watercraft than the other. The blade 113 is located near the stern. The blade has a balanced foil shaped cross-section. 10 When the blade 113 is in the retracted position as in Fig. 2A it is in a sleeve in the hull of the kayak When the blade 113 is in the deployed position as in Fig. 2D and 2E, it extends beneath the hull of the watercraft. The blade is rotationally movable between the retracted and deployed position about a retraction pivot point. The blade is rotated about the retraction pivot point from the retracted position in Fig. 2A, through 90 degrees to the deployed position shown in Fig. 2D. Alternatively, in other embodiments, the blade may be translationally moveable between retracted and deployed positions, for example via a sliding mechanism.

The blade 113 is a rudder and is laterally movable relative to the hull when the rudder is in the deployed position as shown in Fig. 2E. The rudder is laterally movable by rotating about a laterally central steering pivot point. Fig. 2E shows the rudder rotated 22.5 degrees towards starboard. The rudder may be rotatable between at least 22.5 degrees port and 22.5 degrees starboard, for example, between port 45 degrees and 45 degrees starboard.

In this embodiment, the steering and retraction pivot points have the same location.

Fig. 3 and Fig. 4 show a foot control module comprising a foot-operable retraction actuator 114 and a foot-operable steering actuator 115. The foot control module is part of the blade 30 control assembly of the sea-kayak which also includes a blade-retraction mechanism, and control lines.

Actuation of the retraction actuator 114 causes the blade-retraction mechanism to move the blade between the retracted position and the deployed position. The retraction actuator 114 and the blade-retraction mechanism are connected via retraction and deployment control lines 119. The retraction actuator 114 is a slider. The user may push the slider to the left and right with their foot. Pushing the slider in one direction causes the retraction line to be pulled and the blade to be moved towards the retracted position by the blade retraction mechanism and pushing the slider in the other direction causes the deployment line to be pulled and the blade to be moved towards the deployed position by the blade retraction mechanism. The retraction and deployment lines are connected at the slider and at the blade retraction mechanism and act together as a two-way positive pull system, so that both lines are always under tension. The retraction actuator 114 further has a gearing mechanism to cause the retraction and deployment lines to be pulled a shorter distance than the distance by which the slider is moved.

As shown in Fig. 4, each control line has a fore-end fixed to a respective control line fixing point 131 inside the hull. Each control line 116, 119 passes through a plurality of rings of the foot control module, the rings being operable by the user via the foot control module to change the length of the path of the control lines from the fixing points, through the rings.

The control lines are substantially parallel to one another and to a fore-aft axis of the watercraft, except for their path through the rings of the foot control module. By fixing the control lines to the fixing points 131 in the hull and using the rings to manipulate the path of the control lines, the foot control module may be moved relative to the control line fixing points so as to act on a different section of the control lines, but the action of the foot control module to pull the control lines to operate the blade retraction mechanism and steering mechanism remains the same.

The fixing point for the steering lines 116 is laterally central on the watercraft. The port steering line passes from its fixing point to a middle port ring 132 on the steering actuator, then to a wide port ring 133 on the steering actuator and then to the steering mechanism. The starboard steering line passes from its fixing point to a middle starboard ring on the steering actuator, then to a wide starboard ring on the steering actuator and then to the steering mechanism. The middle rings are closer to the lateral centre of the watercraft than the wide rings. In this way, operation of the steering actuator 115 changes the length of the path of the steering lines 116 through the foot control module.

The path of the retraction and deployment control lines through the rings provides a gearing system, such that movement of the retraction actuator 114 may cause a smaller movement by the retraction and deployment control lines 119. In this way, the foot-operable retraction actuator requires a relatively larger movement which is easier for a user to perform.

The rings comprise a retraction floating ring 130, through which the retraction control line passes and through which an operation line 135 of the foot control module also passes, the operation line being attached to the retraction actuator and fixed to the foot control module at its end. The retraction control line passes through a first fixed retraction ring 136 on the foot control module, through the floating retraction ring 130 and then through a second fixed retraction ring 137 on the foot control module. In this way, movement of the retraction actuator 114 causes the operation line 135 to move the floating retraction ring 130 and thereby change the length of the path through the foot control module of the retraction control line.

The rings may further comprise a deployment floating ring 134, through which the deployment control line passes and through which the operation line of the foot control module also passes, the operation line being attached to the retraction actuator 114. The deployment control line passes through a first fixed deployment ring on the foot control module, through the floating deployment ring 134 and then through a second fixed deployment ring on the foot control module. In this way, movement of the retraction actuator causes the operation line to move the deployment ring and thereby change the length of the path through the foot control module of the deployment control line.

Actuation of the steering actuator 115 causes the rudder to move towards the port or starboard of the watercraft. The foot-operable steering actuator 115 includes a left pedal and a right pedal, which in this embodiment are formed by one rocker pedal. Pushing the left pedal causes the blade to be moved towards a first one of the port and starboard sides of the watercraft and pushing the right pedal causes the blade to be moved towards a second one of the port and starboard sides of the watercraft. The steering can be switched between a standard or reverse steering configuration.

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The foot control module is mounted on an inner wall 117 of the hull in the cockpit section 103 on fore-aft lockable sliding mechanism 118 which is bonded to the hull. The foot control module is slidable along the sliding mechanism 118. This allows adjustment of the position of the foot control module according to the leg length or preference of a user as shown by arrow S in Fig. 4. The foot control module can be moved forwards and back to suit different leg lengths without having to adjust the cord lengths, as they adjust automatically due to the path taken through the rings of the foot control module.

The control lines include steer lines 116 including a port steer line and a starboard steer line. The steer lines 116 are operable by the pedals to laterally move the rudder. The port steer line is configured to be pulled by the left pedal to cause the rudder to move towards a first one of the port and starboard sides of the watercraft. The starboard steer line is configured to be pulled by the right pedal to cause the rudder to move towards a second one of the port and starboard sides of the watercraft. The port and starboard steer lines act together as a two-way positive pull system, so that both lines are always under tension. The port and starboard lines are connected at the rudder and indirectly by the foot control module.

The steer lines are switchable between standard steering and reverse steering configurations, wherein in the standard configuration, the first side is the port side of the watercraft and the second side is the starboard side and in the reverse configuration the first side is the starboard side of the watercraft and the second side is the port side. In this way, the water craft can be adapted to user preferences on steering configuration.

In use, it is possible to retract and/or adjust the rudder using the feet as well as steer the kayak using the feet, thereby allowing the user to keep both hands on their paddle for propulsion and stability.

The blade retraction mechanism is shown in Figs 5 to 7. The retraction and deployment lines 119 are connected to each other around the pulley wheel 120 as shown in Fig 5. The control lines 119 are not shown in Figs. 6 and 7. The retraction and deployment control 5 lines pass through the fulcrum of the rudder.

The pulley wheel 120 is connected to the blade 113 via a cog system. The cog system includes a first cog 121, axially connected to the pulley wheel 120 and a second cog 122, axially connected to the blade at the pivot point 123. The first and second cogs are operably 10 connected by a belt 124.

Rotation of the pulley wheel 120 causes the first cog 121 to turn. This causes the belt 124 to move the second cog 122 which in turn causes the blade 113 to pivot about the retraction pivot point 123 and thereby move between the retracted and deployed positions.

In other embodiments, the cog system may be omitted and the pulley wheel may be directly connected to the blade at the pivot point 123. This reduces the complexity of the blade retraction mechanism. The retraction and deployment control lines may pass through the fulcrum of the rudder and to the pulley wheel at point 123.

The control lines are located entirely inside of the shell of the kayak. As shown in Fig. 8, in the cockpit section 103, the control lines 116, 119 pass through a wall of the cockpit via gaskets 125 into a sealed section of the kayak. This keeps the control lines safe from damage by the user in the cockpit.

In this embodiment, the kayak comprises a plurality of sections 101 to 105. At each of the joints between sections 103, 102 and 101, through which the control lines 116, 119 travel, each of the control lines passes through a respective first gasket 126 at on a first section and a respective second gasket on a second section, the first and second gaskets being configured to meet one another when the first and second sections are joined. An example of this can be seen in Fig. 8.

As shown in Fig. 8, the kayak further comprises conduits 127 surrounding a portion of each of the control lines. The conduits 127 surround the control lines 116, 119 as the control lines pass through watertight sections of the kayak. The conduits 127 each surround a respective control line 116, 119 between two walls of a section of the kayak. The control lines each pass through a respective gasket 126 in each of the walls, the conduits 127 and gaskets 126 providing a sealed passage through the section for the control line.

Each control line has a respective sleeve. The sleeves are fed through the conduits once the sections are joined from the tail to the cockpit. The control lines are then connected via the foot control module in the cockpit section. These sleeves are sealed as they exit to the tail with the rudder mechanism, so no water can enter the internal spaces of either between the seat and cockpit mould, or the rear section, or the tail section.

The blade-retraction mechanism may further comprise a rounded tapered retraction guide.

In this way, in the event of catching weeds, rocks or other obstructions, the blade will centre itself and retract inside the kayak.

The kayak is formed of a series of five monocoque sections 101 to 105, each comprising at least part of the deck and at least part of the hull. The kayak comprises a composite, such as carbon fibre, fibreglass, kevlar, aramids and/or organic materials.

An example method of manufacture of the kayak 100 will now be described. The method includes forming the deck and hull, forming the blade 113, forming the blade control assembly, assembling the blade control assembly in the deck and hull, and attaching the blade 113 to the hull, such that it is movable by the blade-retraction mechanism relative to the hull between the retracted position and the deployed position.

Forming the deck and hull may comprise forming a plurality of sections 101 to 105, the sections each comprising a part of the deck and a part of the hull. Forming the deck and hull may comprise forming a monocoque, or a series of monocoques. Forming the deck and hull and/or blade and/or blade control assembly may comprise using carbon fibre, for example, pre-impregnated (Prepreg) carbon fibre including epoxy resin. Forming the deck and hull and/or blade and/or blade control assembly may comprise 3D printing or rotomolding. Forming the blade and/or blade control assembly may comprise using aluminium, steel, wood or other materials.

Although particular embodiments of the disclosure have been disclosed herein in detail, this has been done by way of example and for the purposes of illustration only. The aforementioned embodiments are not intended to be limiting with respect to the scope of the appended claims.

It is contemplated by the inventors that various substitutions, alterations, and modifications may be made to the invention without departing from the scope of the invention as defined by the claims. For example, in other embodiments, the kayak may be formed of other composite materials, and/or by other manufacturing methods such as 3D printing. In other embodiments, the kayak may be formed of plastic. The same principles may be applied to other watercraft such as other types of kayak, a stand-up paddleboard (SUP), a canoe, a row boat, surf-ski, dragon boat or any other type of hand-powered watercraft.

Claims

CLAIMS1. A hand-powered watercraft comprising: a hull, a blade, positioned closer to a stern of the watercraft than a bow, the blade being movable relative to the hull between a retracted position and a deployed position, and a blade control assembly, the control assembly comprising a foot-operable retraction actuator, a blade-retraction mechanism, and control lines, the blade-retraction mechanism being actuatable by the retraction actuator via the control lines to move the 10 blade between the retracted position and the deployed position.
2. A hand-powered watercraft according to claim 1, wherein the blade is a rudder and at least part of the rudder is laterally movable relative to the hull when the rudder is in the deployed position, and the blade control assembly further comprises a foot-operable steering actuator, the rudder being actuatable by the steering actuator to laterally move the rudder relative to the hull.
3. A hand-powered watercraft according to claim 2, wherein the foot-operable retraction actuator and the foot-operable steering actuator are provided on a foot control module, the foot control module being mounted on an inner wall of the hull.
4. A hand-powered watercraft according to claim 3, wherein the foot control module is mounted on a fore-aft lockable sliding mechanism 25
5. A hand-powered watercraft according to any preceding claim, wherein when the blade is in the retracted position, it is located in a sleeve in the hull of the watercraft and when the blade is in the deployed position, it extends beneath the hull of the watercraft.
6. A hand-powered watercraft according to any preceding claim, wherein the control lines are entirely inside of a shell of the watercraft formed by the deck and the hull.
7. A hand-powered watercraft according to any preceding claim, wherein the control lines comprise a retraction line and a deployment line, the retraction line being configured to be pulled by the retraction actuator to cause the blade-retraction mechanism to move the blade towards the retracted position and the deployment line being configured to be pulled by the retraction actuator to cause the blade-retraction mechanism to move the blade towards the deployed position.
8. A hand-powered watercraft according to claim 7, wherein the retraction and deployment lines are connected to each other at the blade retraction mechanism. 10
9. A hand-powered watercraft according to any of claims 2 to 4, or claims S to 8 when dependent on claims 2 to 4, wherein the control lines comprise a port steer line and a starboard steer line, the steer lines being operable by the foot-operable steering actuator to laterally move the rudder, and the port and starboard lines are connected at a rudder steering mechanism.
10. A hand-powered watercraft according to any preceding claim, wherein the watercraft comprises a plurality of sections, the sections being releasably joinable to neighbouring sections at joints and at each of the joints, each of the control lines passes through a respective first gasket at on a first section of the joint and a respective second gasket on a second section of the joint, the first and second gaskets being configured to meet one another when the first and second sections are joined.
11. A hand-powered watercraft according to claim 10, wherein the watercraft further comprises conduits, each conduit surrounding a portion of a respective one of the control lines between two walls of a section of the watercraft, thereby providing a sealed passage through the section for the control line.
12. A hand-powered watercraft according to any preceding claim, wherein the hand-30 powered watercraft is a kayak.
13. A method of manufacture of a watercraft according to any preceding claim, the method comprising: forming the hull, forming the blade, forming the blade control assembly, assembling the blade control assembly in the hull, and attaching the blade to the hull, such that it is movable by the blade-retraction mechanism relative to the hull between the retracted position and the deployed position.
14. A method according to claim 13, wherein forming the hull comprises forming a plurality of sections, the sections each comprising a part of the hull.