WATERCRAFT PROPULSION SYSTEM

Abstract

A power and control module for a watercraft propulsion system having an electric motor unit is disclosed. In one embodiment. the module includes a housing having a first surface including a first region for receiving an appendage supporting or containing the electric motor unit and a second surface including a second region for contacting an underside of a hull of the watercraft; an electrical power source located within the housing; and an electrical interface for completing an electrical circuit including the electrical power source and the electric motor unit.

Claims

1. A power and control module for a watercraft propulsion system having an electric motor unit, the module comprising: a housing having a first surface including a first region for receiving an appendage supporting or containing the electric motor unit and a second surface including a second region for contacting an underside of a hull of a watercraft; an electrical power source located within the housing; and an electrical interface for completing an electrical circuit including the electrical power source and the electric motor unit.

2. The power and control module according to claim 1, further including control electronics located within the housing, the control electronics operably associated with the electrical power source to control an operational power of an electric motor of the electric motor unit.

3. The power and control module according to claim 2, wherein the control electronics includes a receiver for receiving a command signal communicated by a transmitter of an external controller module.

4. The power and control module according to claim 3, wherein the receiver is a wireless receiver and wherein the external controller module is a wireless transmitter.

5. The power and control module according to claim 1, wherein the housing includes a body having plural through holes for receiving a respective fastener therethrough for securing the appendage to the hull via the power and control module in use.

6. The power and control module according to claim 5, wherein the body is a generally brick-shaped element, wherein the first surface is an upper or top surface of the body, and wherein the second surface is a lower or underside surface of the body.

7. The power and control module according to claim 5, wherein the plural through holes have a mapping which corresponds with a mapping of plural holes located on the underside of the hull.

8. A power and control module according to claim 1, wherein the housing includes a nose section, the nose section being removable from a body of the housing to access an interior compartment of the housing.

9. The power and control module according to claim 8, wherein the nose section is shaped to improve hydrodynamic flow over the body of the housing in use.

10. The power and control module according to claim 1, wherein the housing includes an aft section, the aft section being removable from a body of the housing to access an interior compartment of the housing.

11. The power and control module according to claim 10, wherein the removable aft section is shaped to improve hydrodynamic flow over the body of the housing in use.

12. A watercraft propulsion system comprising: a power and control module including: a housing having a first surface including a first region for receiving an appendage supporting or containing an electric motor unit and a second surface including a second region for contacting an underside of a hull of a watercraft; an electrical power source located within the housing; and an electrical interface for completing an electrical circuit including the electrical power source and the electric motor unit; and the appendage mechanically attached to the first region of the power and control module; and the electric motor unit mechanically attached to the appendage and electrically connected to the electrical interface of the power and control module.

13. A watercraft propulsion system, comprising: a power and control module including: a housing having a first surface including a first region for receiving an appendage supporting or containing an electric motor unit and a second surface including a second region for contacting an underside of a hull of a watercraft; an electrical power source located within the housing; and an electrical interface for completing an electrical circuit including the electrical power source and the electric motor unit; and the electric motor unit electrically connected to the electrical interface of the power and control module.

14. The watercraft propulsion system according to claim 12, further comprising a controller located within an interior compartment of the housing, the controller being operatively associated with the electrical power source to control an operational power of an electric motor of the electric motor unit depending on wireless command signals transmitted by a transmitter of an external control module, wherein the controller includes a wireless receiver for receiving the wireless command signals, said wireless receiver including an antenna, and wherein the second surface includes a window which is transmissive to the wireless command signals to provide a signal propagation path which allows the wireless command signals to be received by the antenna.

15. A watercraft, comprising: a hull; and a watercraft propulsion system including: a power and control module including: a housing having a first surface including a first region for receiving an appendage supporting or containing an electric motor unit and a second surface including a second region for contacting an underside of the hull of the watercraft; an electrical power source located within the housing; an electrical interface for completing an electrical circuit including the electrical power source and the electric motor unit; and a controller located within an interior compartment of the housing, the controller being operatively associated with the electrical power source to control an operational power of an electric motor of the electric motor unit depending on wireless command signals transmitted by a transmitter of an external control module, wherein the controller includes a wireless receiver for receiving the wireless command signals, said wireless receiver including an antenna, wherein the second surface includes a window which is transmissive to the wireless command signals to provide a signal propagation path which allows the wireless command signals to be receive by the antenna, and wherein the power and control module is positioned and retained between the appendage and the underside of the hull of the watercraft.

16. The watercraft according to claim 15, wherein the watercraft is a foiling surf or a paddle board and wherein the appendage is a foiling unit having a mast to which the electric motor unit is attached for slidable adjustment therealong.

17. The watercraft according to claim 15, wherein the watercraft is a surf board or a kayak and wherein the appendage is a fin having an integrated electric motor unit.

18. A watercraft comprising: a hull having an underside and an upper side or deck; a power and control module located on the underside of the hull, the power and control module comprising: a housing having a first region for receiving an appendage in a downwardly depending orientation from the housing, the appendage for supporting or containing an electric motor unit; an electrical power source located within the housing; an electrical interface for completing an electrical circuit including the electrical power source and the electric motor unit; and control electronics located within the housing, the control electronics operably associated with the electrical power source to control an operational power of the electric motor unit, the control electronics including a receiver having an antenna for receiving a wireless command signal communicated by a transmitter of an external controller module through the hull of the watercraft.

19. The watercraft according to claim 18, wherein the housing includes a window which is transmissive to wireless signals transmitted by the external controller, said window being in contacting relationship with the underside of the hull, wherein the window and hull provide a signal propagation path which allows the wireless signals to be received by the antenna.

20. The power and control module according to claim 4, wherein the second surface includes a window which is transmissive to wireless signals, and wherein the wireless receiver includes an antenna for receiving the wireless signals communicated through the window, said wireless signals transmitted by the external controller module.

Description

BRIEF DESCRIPTION OF DRA WINGS

[0036] Embodiments of the present disclosure will be discussed with reference to the accompanying drawings wherein:

[0037] FIG. 1 is an upper front-side perspective view of a power and control module for a watercraft propulsion system according to an embodiment;

[0038] FIG. 2 is a lower front-side perspective view of a power and control module for a watercraft propulsion system according to an embodiment;

[0039] FIG. 3 is an exploded perspective view of the power and control module shown in FIG. 1;

[0040] FIG. 4 is an underside perspective exploded view of a watercraft with a watercraft propulsion system including the power and control module shown in FIG. 1 and an electric motor unit suitable for use with an embodiment of the power and control module fitted to an appendage in the form of a mast and a fuselage;

[0041] FIG. 5 shows an example of the electric motor unit shown in FIG. 4 fitted to the mast of FIG. 4, showing an example range of adjustment of the electric motor unit;

[0042] FIG. 6 shows another example of a watercraft fitted with a watercraft propulsion system according to an embodiment;

[0043] FIG. 7 shows a side view of another power and control module according to an embodiment;

[0044] FIG. 8 is a functional block diagram of another watercraft propulsion system according to an embodiment;

[0045] FIG. 9 shows a signal propagation path for a wireless signal for a watercraft fitted with a watercraft propulsion system according to an embodiment;

[0046] FIGS. 10 and 11 show an example of a watercraft fitted with a watercraft propulsion system according to an embodiment in use;

[0047] FIG. 12 is an exploded perspective view of a power and control module according to another embodiment of the present disclosure;

[0048] FIG. 13 is an upper front-side perspective view of a power and control module for a watercraft propulsion system according to another embodiment of the present disclosure;

[0049] FIG. 14 is an underside perspective view from the rear of the power and control module shown in FIG. 13;

[0050] FIG. 15 is an underside perspective and partially exploded view of the power and control module shown in FIG. 13 showing an example connector arrangement disconnected;

[0051] FIG. 16 is a close-up perspective view of the aft section of the power and control module shown in FIG. 13 showing the example connector arrangement; and

[0052] FIG. 17 is an exploded perspective view of the power and control module shown in FIG. 13.

DESCRIPTION OF EMBODIMENTS

[0053] Referring now to FIGS. 1 to 4 there is shown a power and control module 100 for a watercraft propulsion system 10 (ref. FIG. 4) according to an embodiment of the disclosure. Module 100 includes a housing 104 having a first surface 106, a second surface 110, and an electrical power source 114 (ref. FIG. 3) located within an interior compartment of the housing 104.

[0054] As shown in FIG. 4, first surface 106 (ref. FIG. 2) includes a first region 108 providing a landing for receiving an appendage 180 supporting an electric motor unit 170 of the watercraft propulsion system 10. Second surface 110 (ref. FIG. 1) contacts an area of an underside 202 of a hull 204 (ref. FIG. 4) of the watercraft 200 when fitted to the watercraft 200.

[0055] Before continuing further, in the description that follows the power and control module 100, and the watercraft propulsion system 10 of which the module 100 is one component, will be described in terms of a propulsion system 10 for a watercraft 200 (ref. FIG. 3) in the form of a board, such as a foiling paddle or surf board. However, it is to be understood that embodiments of the present disclosure are not to be so limited. For example, it is possible that the module 100 for a watercraft propulsion system 10 may be used as a propulsion system for other types of watercraft. Examples of other types of watercraft include a conventional surf board, a conventional paddle board, a kayak, a canoe, a wake board, a dinghy with a rigid hull (such as a rigid inflatable boat), or the like.

[0056] Appendage 180 may comprise a watercraft control or steering appendage such as a fin, foiling unit, rudder or keel with the type of appendage 180 depending on the watercraft 200. The appendage 180 shown in FIGS. 4 and 5 comprises a foiling assembly 182 which itself comprises a plate element 184, a fuselage 186, and a mast 188 disposed between the plate 184 and the fuselage 186. Other appendage configurations may be suitable.

[0057] Referring now to FIGS. 1 and 2, in the illustrated embodiment second surface 110 is an upper surface of the housing 104 and first surface 106 is a lower or underside surface of the housing 104. In the present case, the first surface 106 and the second surface 110 are depicted as planar surfaces. However, it will be appreciated that other surface configurations may be used. For example, second surface 110 may be shaped to interface with the correspondingly shaped area of the underside 202 of the hull 200 with which it contacts.

[0058] In present case, the first surface 106 and the second surface 110 are parallel planar surfaces located in a spaced apart relationship defining the height (H) of the housing 104. Side walls 120, 122 (ref. FIG. 3) depend between and along longitudinal edges of the first and second surfaces 106, 110.

[0059] As shown in FIG. 3, an electrical power source 114 and associated control electronics 116 for operating the electric motor unit 170 are located within the housing 104. The electrical power source 114 and the associated control electronics 116 will be described in more detail below.

[0060] An electrical interface 118 is provided for completing an electrical circuit including the electrical power source 114 and the electric motor unit 170. Electrical interface 118, shown here as cable, completes an electrical circuit including the electrical power source 114, the control electronics 117, and the electric motor unit 170.

[0061] In certain embodiments, the cable of the electrical interface 118 may be integrated or hard wired interface so as to directly couple the power source 114 and associated control electronics 116 with the electric motor unit 170.

[0062] In other embodiments, and as will be described in more detail below, the cable of the electrical interface 118 may include one or more electrical connectors suitable for submersible operation to complete the circuit including the electrical power source 114, the control electronics 116, and the electric motor unit 170.

[0063] In other embodiments, the electrical interface 118 may be integrated within or secured to the appendage 180.

[0064] In embodiments including an appendage 180 of the type shown in FIG. 4, the electric motor unit 170 may be slidably mounted on and supported by the mast 188 of the appendage 180. Accordingly, in some embodiments, and as best shown in FIG. 5, the electrical interface is configured to permit sliding adjustment of the position of the electric motor unit 170 relative to the housing 104 when the electric motor unit 170 is supported by the appendage 180. Such a configuration may be required where, for example, the electric motor unit 170 is slidably adjustable in position along a longitudinal extent of the mast 188. Adjustment of this type may allow a user to position the electric motor unit 170 at a position or depth which suits their use requirements. For example, the electric motor unit 170 may be lowered or set to a deeper position if the user requires the electric motor unit 170 to remain submerged for a longer period as the board 200 lifts out of the water when foiling or it may be raised or set to a shallower position if the user requires the electric motor unit 170 to lift from a submerged position earlier water when foiling, as the board 200 lifts out of the water.

[0065] It will be appreciated that it is not essential that the position of the electric motor 170 be adjustable since, in some embodiments, the electric motor 170 need not be adjustable. One example of a watercraft (shown here as a non-foiling surf board) fitted with a watercraft propulsion system 10 in which the position of the motor need not be adjusted is FIG. 6. In this example, module 100 is fitted to the underside 302 of a conventional surf board 300 and the electric motor unit 170 is attached to an appendage 180 in the form of a fin 304. Module 100 and electric motor unit 170 are the same as those described above.

[0066] In embodiments, the electric motor unit 170 includes a motor pod which is removably fitted to the appendage 180 to secure the electric motor unit 170 thereto. Such a pod may have an aperture having a profile which accepts or corresponds with the cross-sectional profile of a length portion of the appendage to which the motor pod, and thus the electric motor unit 170, is fitted.

[0067] Continuing now with reference to FIG. 4, in embodiments the power and control module 100 is located and retained between the underside 202 of the hull 204 of the watercraft 200 and the appendage 180.

[0068] In some embodiments, the first region 108 of the module 100 provides a landing for receiving the appendage 180 in a retained relationship therewith in a configuration which allows the appendage 180, and thus the electric motor unit 170, to be readily fitted to and removed from the watercraft 200. An advantage of this arrangement is that it may allow for ready replacement of the appendage 180 with an appendage 180 having a different configuration, such as a different profile or hydrodynamic performance characteristics, or indeed a different electric motor unit 170. When the appendage 180 is fitted, power and control module 100 is retained between the underside 202 of the hull 204 of the watercraft 200 and the appendage 180.

[0069] Returning now to FIG. 4, and as is described above, in use the module 100 is retained between the underside 202 of the hull 204 of the watercraft 200 and the appendage 180. In this arrangement, the appendage 180 will depend generally downwardly from the first region 108 of the first surface 106 and thus from the hull 204 of the watercraft 200.

[0070] With reference again to FIG. 3, housing 104 includes a body 124 having a generally brick-shaped configuration characterised by the arrangement of the first or upper surface 110, the second or lower surface 106, and the side walls 120, 122. In preference, body 124 includes a hollow interior which is sized and shaped to provide an interior compartment 128 (ref. FIGS. 1 and 2). However, it is also possible that the body 124 may have a solid construction within which other components are moulded or encapsulated. In one example of a solid construction the electrical power source 114 and associated control electronics 116 is encapsulated in a suitable encapsulating material to form the housing 104. In such embodiments, the body 124 may be moulded about the electrical power source 114 and associated control electronics 116. Suitable materials for a moulded type construction would be known to a skilled person.

[0071] A nose section 130 is disposed on a front portion of the body 124. In the present case, the nose section 130 comprises a removable member 132. However, in some embodiments, the nose section 130 may be formed as an integral part of the body 124 and thus the housing 104. One example of a power and control module 100 in which the nose section 130 is formed as an integral part of the body 124, and thus the housing 104, is an assembly 1200 with the body 124 having a moulded type construction in which the nose section 130 forms a part of the moulded construction is shown in FIG. 12. In the embodiment shown in FIG. 12, the housing 104 includes a lid 160 which is removable to access the compartment 128. In certain embodiments the lid 160 comprises or includes a material which is transmissive to wireless signals transmitted by a user operated control 300 (ref. FIG. 9) by for receipt control electronics 116 located within the housing 104 to vary or set the speed of the electric motor of the electric motor unit 170 (ref. FIG. 9) and thus vary the thrust generated by a propeller of the electric motor unit 170.

[0072] Although it is not essential that embodiments include a nose section 130 in the form of a removable member 132, it is nevertheless preferred that a removable member 132 be provided, particularly in embodiments including an interior compartment 128, since the removable member 132 may allow access to the interior compartment 128 for removal of the electrical power source 114 and/or associated control electronics 116 forwardly for serving and/or replacement.

[0073] In the present case, removable member 132 is attached to the body 124 via a first set of threaded fasteners 134 which are inserted into through corresponding holes 136 of the removable member 132 and into corresponding threaded holes 138 of the body 124. Once so inserted, the fasteners 134 may be tightened to urge a rim 140 of the removable member 132 into sealed relationship with a corresponding rim 142 of the body 124 to resist water ingress when the housing 104 is immersed in water during normal use. A seal or gasket (not shown) of a suitable material may be located between the rims 140, 142 if required to maintain or improve seal integrity. As will be described in more detail below, other arrangements for attaching the removable member 132 to the body 124 are possible.

[0074] In certain embodiments, the nose section 130 is shaped to reduce hydrodynamic drag in use when compared to a front facing planar surface. In the present case, the nose section 130 comprises a spoon-shaped bow. However, it will be appreciated that other shapes may be used.

[0075] An aft section 144 is located on a rear portion of the body 124. The aft section 144 is shaped to reduce hydrodynamic drag in use when compared to a rear facing planar surface. In the present case, the aft section 144 is a spoon-shaped section. However, it will be appreciated that other shapes may be used.

[0076] In the present case, the aft section 144 comprises a removable rear member 146 as shown in FIGS. 1 and 2. In certain embodiments, removing the rear or aft member 146 provides access to the interior compartment 128 of the housing 104 to permit removal of the electrical power source 114 and/or associated control electronics 116 rearwardly. It is not essential that embodiments include an aft section 144 in the form of a removable rear member 146 since, in some embodiments, the aft section 144 may be an integral part of the body 124 and thus the housing 104. Nevertheless, it is preferred that a removable rear member 146 be provided so as to allow access to the interior compartment 128 as may be required to remove the electrical power source 114 and/or associated control electronics 116 rearwardly for servicing and/or replacement.

[0077] The removable rear member 146 shown here is attached to the body 122 via a set of threaded fasteners 148. Each fastener 148 of the set is inserted through a respective hole 150 of the removable aft member 146 and into a corresponding threaded hole 152 of the body 124. Once so inserted, each fastener 148 may be tightened to urge a rim 154 of the removable aft member 146 into sealed relationship with a corresponding rim 156 of the body 124 to form a seal which resists water ingress when the housing 104 is immersed in water during normal use. A seal or gasket (not shown) of a suitable material may be located between the rims 154, 156 if required to maintain or improve seal integrity.

[0078] In view of the above, it will be appreciated that, in certain embodiments, the housing 104 includes the body 124, removable member 132, and the removable rear member 146 in an arrangement which is capable of forming a sealed interior compartment 128 which is accessible forwardly (by removing the nose member 132) and/or rearwardly (by removing the aft member 146).

[0079] In other embodiments, the housing 104 includes the body 124 and either the removable nose member 132 or the removable aft member 146 arranged to form a sealed interior compartment which is accessible forwardly or rearwardly respectively.

[0080] In still other embodiments, the housing 104 includes the body 124 formed with an integral nose section 130 and an integral aft section 144 which are shaped as required to improve hydrodynamic flow over the module 100. In this and other embodiments, the housing 104 may include a removable lid which is removable to access the compartment 128.

[0081] Continuing now with reference to FIGS. 1 and 2, it can be seen that a set of plural through-holes 158 are positioned and arranged to extend through the body 124 of the housing 104. Each hole 158 has a diameter sufficient to receive a fastener 162 (ref. FIG. 3) having a diameter and length suitable for retaining the module 100 and the appendage 180 to the underside 202 of the watercraft 200 in normal use.

[0082] In the present case, each of the plural through-holes 158 provides a channel extending through a solid region of the body 124 which prevents water ingress into the interior compartment 128 of the housing 104. In the present case, a set of four holes 158 is depicted. However, it is possible that a different number of holes 150 may be used.

[0083] The body 124 may include structural reinforcement to reduce risk of failure of the housing 104 during compressive loads which may be generated when the module 100 is retained to the hull 204 in normal use. One example of structural reinforcement involves providing additional material bulk about each hole 158. Another example of structural reinforcement involves providing a sleeve about each hole 158, such as a metal sleeve.

[0084] With reference now to FIG. 4, at least some of the plural through-holes 158 of the module 100 have a mapping or pattern which corresponds with a mapping or pattern of plural threaded holes 208 on the underside 202 of the watercraft 200. The plural threaded holes 208 on the underside 202 of the hull 204 of the watercraft 200 would typically receive fasteners required to secure the appendage 180, such as a foiling assembly 182, to the watercraft 200 directly. However, in embodiments, the module 100 is positioned and retained between the underside 202 of the hull 204 of the watercraft 200 and the appendage 180 using fasteners 162 which pass through a plate element 184 of the appendage 180 and the module 100 to be received by the plural threaded holes 208 on the underside 202 of the hull 204 of the watercraft 200.

[0085] In the present case, plate element 184 includes a mapping of a set of plural holes which positionally correspond to the mapping 206 of the plural threaded holes 208 on the underside 202 of the watercraft 200 and thus with the mapping of plural threaded holes 158 of the module 100. This correspondence permits the plate element 184 of foiling assembly 182 to be contactably secured to the watercraft 200 via module 100 using suitable threaded fasteners 162 (ref. FIG. 3). During fitment, the module 100 is positioned between the underside 202 of the hull 204 of the watercraft 200 and the plate 184 and positioned so that the plural threaded holes 208 located on the underside 202 of the hull 204, the plural through-holes 158 of the module 100, and the plural holes of the plate 184 are aligned in overlapping relationship to receive the threaded fasteners 162. In this way, tightening the fasteners 162 clamps and holds the housing 104, and thus the module 100, in position between the plate element 184 and the underside 202 of the hull 204 of the watercraft 200 using the pattern of threaded holds 208.

[0086] As briefly described above, and with reference again to FIG. 3, an electrical power source 114 and associated control electronics 116 are located within the housing 104. In the present case, electrical power source 114 includes plural batteries 220 of a type and circuit arrangement which provide an output voltage and ampere hour rating based on the requirements of the control electronics 116, the electric motor unit 170, and usage demands. Any suitable types of batteries may be used. One example of a suitable battery is a rechargeable lithium ion battery, such as a 21700 4000 mAh 35A cylindrical battery manufactured by Samsung. Other battery types may be suitable depending on the particular requirements. For example, it is possible that prismatic or pouch type rechargeable Lithium-Ion batteries, or of a different cell chemistry, may be suitable.

[0087] Batteries 220 may be arranged as a battery pack including a series circuit combination of the batteries, or a parallel circuit combination of the batteries 220, or a combination of parallel and series circuits. In this respect, FIG. 7 depicts an alternative embodiment of a module 100 including an alternative arrangement of batteries 220 which allows for a reduction in the height (H) profile of the module 10.

[0088] In certain embodiments, the electrical power source 114 includes protection and/or regulation circuits such as voltage regulation circuits, over voltage protection circuits, and reverse current protection circuits. It is also possible that the electrical power source 114 may include monitoring and communication circuits for communicating battery status information, such as state of charge or predicted usage time remaining. The communication circuit may include, for example, a short range wireless transmitter such as a Bluetooth, Wifi, or ZigBee transmitter for transmitting battery status information.

[0089] Control electronics 116 may include a signal receiver and processing unit for processing information communicated by a control signal transmitted by a user operated control to generate, using a motor controller module, a motor control signal which varies or sets the speed of the electric motor of the electric motor unit 170 and thus varies the thrust generated by a propeller 172 of the electric motor unit 170. In certain embodiments, the user operated control may be a wired device in wired signal communication with the control electronics 116. In other embodiments, the user operated control is a wireless device and the control electronics 116 is configured to support wireless signal communication with the user operated control via a suitable wireless signalling. One example of a suitable wireless signal is a 2.4 GHz FSK signal having a transmission power of between 1 mW and 10 mW. Other wireless signal may also be suitable.

[0090] Referring now to FIG. 8 there is shown a functional block diagram for an embodiment of a watercraft propulsion system 10 including a wireless user control 300 in wireless signal communication with module 100. Module 100 communicates control signals to the electric motor unit 170 via electrical interface 118 depending on information received from the wireless user control 300. Electrical interface 118 may support a three-phase type control provided by a three-phase motor controller of the control electronics 116.

[0091] Wireless user control 300 shown in FIG. 8 includes an electrical power source 302 (such as a rechargeable battery), user control(s) 304, control electronics 306, and communications interface 314.

[0092] User control 304 may comprise a throttle switch or lever having a positional dependent parameter which is sensed by processor 306 and translated into the data signal for transmission as a wireless control signal for signal communication to the module 100 by communications interface 314.

[0093] In the present case, control electronics 306 comprises a processor 308 in coupled communication with a memory 310 storing a set of program instructions which are executable by the processor to translate a signal from user control 304 into an instruction for communications interface 314 to transmit as information in wireless signal via an antenna 316 of the communications interface 314. The wireless user control 300 will include a suitable housing or other form of protection to prevent water ingress during normal use.

[0094] Continuing now with reference to FIG. 8, the module 100 shown here includes the electrical power source 114, control electronics 116, wireless signal receiver 702, and motor controller 706. In the present case, control electronics 116 includes a processor 704 in coupled communication with a memory 708 storing a set of program instructions which are executable by the processor 704 to translate a signal from wireless signal receiver 702 into an instruction for the motor controller 706. Motor controller 706 transmits a control signal via electrical interface 118 to the electric motor unit 170 depending on the operation of the wireless user controller 300.

[0095] Electric motor unit 170 may comprise a brushless outrunner type electric motor, having ceramic bearings. The motor may include an epoxy impregnated stator for improved corrosion prevention. The type and characteristics of the motor will vary according to the intended application and type of watercraft. Suitable electric motors would be known to a skilled person.

[0096] Embodiments which include a wireless user operated control are expected to provide practical advantages compared to a wired embodiment. For example, the wireless user operated control may be used in a way which does not require a physical connection between the wireless user operated control and the watercraft. Use of a wireless controller also avoids the need for cabling between the user operated control and the module which may otherwise interfere with the user.

Example 1

[0097] FIGS. 10 and 11 show a watercraft 200 in the form of a foiling paddle board 200 in use by a user (not shown). In the illustrated example, watercraft propulsion system 10 is fitted to the board 200 and controlled by a wireless user operated controller 300 (ref. FIG. 9) to transmit a wireless control signal 318 to the module 100.

[0098] In the embodiment depicted in FIG. 9, the wireless controller 300 is fitted to or integrated with paddle 400 so as to be accessible to and operatable by a user when operating the paddle 400 in a standing position. However, it is to be appreciated that, in other embodiments, the wireless controller 300 may be a separate controller which is located or configured for use when a user is positioned in a prone or lying down position on the board 200. For example, in other embodiments, it is also possible that the wireless user operated controller 300 may be attached to the deck of the board 200 via suitable means 300.

[0099] In the present case, and as shown in FIG. 9, a signal propagation path between the wireless user operated controller 300 and the wireless receiver 702 (and its associated antenna) in the housing 124 includes an air medium between the wireless controller 300 and the board 200, material forming the hull of the board 200 and the housing 124, and a portion of the housing 124 itself. In embodiments, the hull of the board 200 and at least a portion of the housing 124 are transmissive to the wireless control signal.

[0100] An advantage of embodiments of the present disclosure in which the housing 124 is contactably located on the underside of the hull of the board 200 is that a signal propagation path between the wireless controller 300 and the receiver 702 of the module 100 is provided which does not usually pass through water, despite the module 100 being located on the underside of the board 200 and thus below the waterline of the board 200 when the board 200 is floating. By providing a signal propagation path which does not usually pass through water, a reliable control channel may be provided even in circumstances when the module 100 is located below the waterline of the board 200 when floating. Furthermore, by retaining the module 100 to the waterline of the board 200 using an existing hole pattern usually used to secure the appendage directly to the board 200, the need to modify the hull 300 to accommodate the module 100 may be avoided.

[0101] In the example shown in FIG. 10, the board 200 is in a floating state in a body of water whereby the board's buoyancy supports the user and the board 200. In this state, a wireless user operated controller 300 may be operated by the user to communicate a wireless control signal to the module 100 to command the electric motor unit 170 to increase thrust and thus increase the velocity of the board 200 through the water. As the board 200 accelerates, fuselage 186 generates lift which, at a particular velocity, is sufficient to raise the board 200 above the surface of the body of water, as shown in FIG. 11. Once raised above the water, the board 200, and in this example the electric motor unit 170, are no longer immersed in the water and the drag of the foiling paddle board 200 is reduced substantially.

[0102] FIGS. 13 to 17 show another embodiment of a power and control module 210 for a watercraft propulsion system according to an aspect of the present disclosure. The power and control module 210 illustrated in FIGS. 13 to 17 is similar in function to the power and control module 100 described above with reference to FIGS. 1 to 11 and thus includes components which are similar to those of the power and control module 100 described above. In particular, and as shown in FIG. 13, the power and control module 210 includes a housing 124 configured to provide a compartment 128 in which, the electrical power source 114 and the associated control electronics 116 for operating the electric motor unit 170 are located. The electrical power source 114 and the associated control electronics 116 are the same as those described above.

[0103] In the present case, the interior compartment 128 is a hollow interior formed when the removable nose member 132 is attached to the body 124 of the housing 104. In the illustrated embodiment, nose member 132 is attached to the body 124 of the housing 104 by way of a pair of latches 212, shown here as over centre cam type latches, which engage with edges 214 of the removable nose member 132 and which are operable, when so engaged, to urge the rim 140 of the removable member 132 into sealed relationship with a corresponding rim 142 of the body 124 to resist water ingress when the housing 104 is immersed in water during normal use. A seal or gasket (not shown) of a suitable material may be located between the rims 140, 142 if required. An advantage of using latches 212, such as the depicted over centre cam type latches, is that they may allow the removable member 132 to be quickly released from the body 124 for access to the batteries 220 or other interior components of the power and control module 210, such as may be required for servicing and/or replacement.

[0104] The power and control module 210 illustrated in FIGS. 13 to 17 also includes a female connector 216 (ref. FIG. 15), shown here as a three-way socket connector, for mating with a corresponding connector 218 (shown here as a three-way plug connector) terminating the electrical cable to form a normally waterproof connection completing an electrical circuit including the electrical power source 114, the control electronics 116, and the electric motor unit 170 suitable for submersible operation. It is possible that the electrical cable of the electrical interface 118 may be at least partially integrated within the mast 188 of a watercraft so as to at least partially conceal the electrical cable within the mast 188.

[0105] Continuing with reference to FIGS. 13 to 17, the power and control module 210 further includes a window 230 which is attached to the lid 160 of the housing 104 by suitable means. In the present case, window 230 is constructed of a material which is transmissive to wireless signals transmitted by a user operated control 300 (ref. FIG. 9) by for receipt control electronics 116 located within the housing 104 to vary or set the speed of the electric motor of the electric motor unit 170 (ref. FIG. 9) and thus vary the thrust generated by a propeller of the electric motor unit 170. Although in the present case the window 230 is shown as being attached to the lid 160 of the housing 104, it is possible that the lid 160 may be formed so that window 230 is formed integrally with the lid 160. It is also possible that the window 230 may be attached to or integrally formed with another upper surface of the power and control module 210, such as an upper surface of the removable member 132.

[0106] In certain embodiments, the window 230 is constructed of a material which is transmissive to wireless signals transmitted by a user operated control 300 (ref. FIG. 9) and optically transparent to allow for visual inspection of the interior compartment 128 for moisture ingress.

[0107] In the present case, and as is best shown in FIG. 13, an antenna 222, shown here as a stub antenna, for receiving the wireless signal communicated by a transmitter of the external controller module 300 is located in contacting relationship with the window 230. For example, in certain embodiments, the antenna 222 is encapsulated within the window 230 to position the antenna 222 proximal to the upper surface of the lid 160. In such an embodiment, the antenna 222 may be orientated in co-planar relationship with the upper surface of the lid 160. Encapsulating the antenna 222 within the window 230 further reduces separation between the upper surface of the power and control module 210 and the antenna 222 compared to locating the antenna 222 in the interior compartment and thus may reduce signal attenuation of a wireless signal propagating to the antenna 222 over a signal path which includes the hull of the watercraft.

[0108] Antenna 222 is operatively associated and connected to the wireless receiver 702 (ref. FIG. 8) to receive a wireless signal from the wireless user controller 300 (ref. FIG. 9). In the present case, when the power and control module 210 is attached to an underside of a watercraft, the window 230, and thus the antenna 222 is located positionally adjacent to the underside of the watercraft.

[0109] The reference to any prior art in this specification is not, and should not be taken as, an acknowledgement or any form of suggestion that such prior art forms part of the common general knowledge.

[0110] It will be understood that the terms comprise and include and any of their derivatives (e.g. comprises, comprising, includes, including) as used in this specification, and the claims that follow, is to be taken to be inclusive of features to which the term refers, and is not meant to exclude the presence of any additional features unless otherwise stated or implied.

[0111] In some cases, a single embodiment may, for succinctness and/or to assist in understanding the scope of the disclosure, combine multiple features. It is to be understood that, in such a case, these multiple features may be provided separately (in separate embodiments), or in any other suitable combination. Alternatively, where separate features are described in separate embodiments, these separate features may be combined into a single embodiment unless otherwise stated or implied. This also applies to the claims which can be recombined in any combination. That is, a claim may be amended to include a feature defined in any other claim. Further, a phrase referring to at least one of a list of items refers to any combination of those items, including single members. As an example, at least one of: a, b, or c is intended to cover: a, b, c, a-b, a-c, b-c, and a-b-c.

[0112] It will be appreciated by those skilled in the art that the disclosure is not restricted in its use to the particular application or applications described. Neither is the present disclosure restricted in its preferred embodiment with regard to the particular elements and/or features described or depicted herein. It will be appreciated that the disclosure is not limited to the embodiment or embodiments disclosed, but is capable of numerous arrangements, modifications and substitutions without departing from the scope as set forth and defined by the following claims.