ELECTRIC-POWERED BOAT WITH RETRACTABLE HYDROFOIL

BACKGROUND

The embodiments described herein relate to electric-powered watercraft.

In a typical electric motorboat, power is provided from an inboard or outboard electric motor. However, as the energy density of an electric battery is far less than that of a similar volume of petroleum-derived fuel (such as gasoline or diesel), electric boats typically must make a trade-off between available running time and space/weight dedicated to a battery, and within the constraint of battery size, must also trade off range and running speed.

One technique used in some cases to overcome these tradeoffs is the use of a hydrofoil, to lift the watercraft partially or entirely out of the water when travelling faster than some speed, a process known as foiling. Foiling reduces drag on the watercraft and thereby increases average speed and range at a given total energy consumption. Hydrofoils themselves present several design and operational difficulties, including difficulty of dry-land transport of a hydrofoil-equipped watercraft, dynamic stability and control problems while foiling, and an inability to enter or maneuver in shallow water where the hydrofoil may hit or catch on the floor of the body of water.

SUMMARY

An electric-powered watercraft with at least one retractable hydrofoil and an advanced guidance and control system is described. The retractable aspect of the at least one hydrofoil allows for simpler dry-land and shallow-water transport and handling of the watercraft. The guidance and control system allows for improved maneuverability, better stability, greater motor efficiency and reduced power consumption.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating a left side view of an MFA-based watercraft.

FIG. 2 is a diagram illustrating a front plan view of an MFA-based watercraft.

FIG. 3 is a diagram illustrating a bottom plan view of an MFA-based watercraft.

FIG. 4 is a diagram illustrating a perspective view of an MFA-based watercraft.

FIG. 5 is a schematic diagram of the electronic, power and navigational hardware of an embodiment of the watercraft.

FIG. 6 is a diagram illustrating a front plan view of an MFA-based watercraft with an offset-V retraction mechanism.

FIG. 7 is a diagram illustrating a left side view of an MFA-based watercraft with an offset-V retraction mechanism.

FIG. 8 is a diagram illustrating a perspective view of an MFA-based watercraft with an offset-V retraction mechanism.

FIG. 9 is a diagram illustrating a front plan view of an MFA-based watercraft with an inline-V retraction mechanism.

FIG. 10 is a diagram illustrating a left side view of an MFA-based watercraft with an inline-V retraction mechanism.

FIG. 11 is a diagram illustrating a perspective view of an MFA-based watercraft with an inline-V retraction mechanism.

FIG. 12 is a diagram illustrating a front plan view of an MFA-based watercraft with a swing-up retraction mechanism.

FIG. 13 is a diagram illustrating a left side view of an MFA-based watercraft with a swing-up retraction mechanism.

FIG. 14 is a diagram illustrating a perspective view of an MFA-based watercraft with a swing-up retraction mechanism.

FIG. 15 is a diagram illustrating a left side view of an RSA-based watercraft with a double-strut front foil.

FIG. 16 is a diagram illustrating a perspective view of an RSA-based watercraft with a double-strut front foil, viewed from above, behind and to the left (port) of the watercraft.

FIG. 17 is a diagram illustrating a perspective view of an RSA-based watercraft with a double-strut front foil, viewed from above, ahead of and to the left (port) of the watercraft.

FIG. 18 is a diagram illustrating a perspective view of an RSA-based watercraft with a double-strut front foil, viewed from below, ahead of and to the right (starboard) of the watercraft.

FIG. 19 is a diagram illustrating a perspective view of a watercraft steering wheel.

FIG. 20 is a diagram illustrating a perspective view of the drivetrain and RSA of an RSA-based watercraft.

FIG. 21 is a diagram illustrating a perspective view of the lower section of an RSA of an RSA-based watercraft, viewed from above the rear foil.

FIG. 22 is a diagram illustrating a perspective view of the lower section of an RSA of an RSA-based watercraft, viewed from below the rear foil.

FIG. 23 is a diagram illustrating a section of an RSA-based watercraft.

FIG. 24 is a diagram illustrating a cut-away perspective view of an RSA-based watercraft.

FIG. 25 is a diagram illustrating a perspective view of the front foil actuator of an RSA-based watercraft.

FIG. 26 is a diagram illustrating a perspective view of the front foil of an RSA-based watercraft, viewed from behind the front foil.

FIG. 27 is a diagram illustrating a perspective view of the front foil of an RSA-based watercraft, viewed from ahead of the front foil.

FIG. 28 is a diagram illustrating a perspective view of a steering actuator of an RSA-based watercraft.

DETAILED DESCRIPTION

In a typical hydrofoil-equipped watercraft, the hydrofoil (or “foil”) is rigidly mounted to the underside of the watercraft. Herein we describe a watercraft with a foil mounted to a moveable assembly, which assembly is configured to retract by moving up towards the underside of the watercraft when extension of the foil is not required, and to deploy by moving downwards away from the underside of the watercraft when extension of the foil is required. The moving may be actuated by actuators or may be affected through forces created by the primary propulsion motor and control surfaces of the watercraft.

In one embodiment, the watercraft may be equipped with an electric motor-based propulsion system. Such a system preferably comprises at least one propeller driven by at least one electric motor, as well as a battery and motor controller.

The ability of the watercraft to retract the hydrofoil may present several benefits compared to a watercraft with a fixed hydrofoil. A watercraft with a retractable hydrofoil may be able to navigate shallower waters than a watercraft with a fixed hydrofoil can. A watercraft with a retractable hydrofoil may be easier to dock, trailer and transport on land than a more cumbersome watercraft with a fixed hydrofoil. A watercraft with a retractable hydrofoil may be enabled to retract its hydrofoil or allow its hydrofoil to pivot backwards upon hitting an obstacle, or in the event that the watercraft detects an impending collision between an obstacle and the watercraft's hydrofoil assembly; in contrast, in a collision with an obstacle, a watercraft with a fixed hydrofoil may sustain considerable damage to its hydrofoil assembly or to the hull or structure of the watercraft if the impact force were carried through the hydrofoil assembly into the hull.

MFA-Based Watercraft Embodiment

In one embodiment, the watercraft may be equipped with a propulsion system mounted rigidly to, or comprised within, the hydrofoil assembly, making the assembly a motor/foil assembly, or MFA. The propulsion system comprises at least one battery, an electric motor and a propeller attached to the motor. The propulsion system may optionally comprise a motor controller. Since the propulsion system makes up a significant component of the total mass of the watercraft, a unified MFA comprising the foils and propulsion system provides a low centre of mass for the watercraft, making the watercraft inherently more stable and maneuverable. As the MFA remains submerged during regular operation of the watercraft, the MFA's weight is partly offset by the water's buoyant force. The resulting lower effective weight for the watercraft allows for the same lift force to be generated with smaller foils, with concomitant reduction in drag. As well, smaller control surfaces on the foils are needed than with a heavier watercraft, thereby reducing the electrical power and motor size needed to actuate the control surfaces.

Containing the batteries and motor proximally in the MFA may result in an electrically more efficient and safe system, as there is less power loss through cabling, no need for high power cabling into the main body of the watercraft, and no need for high power cabling in the MFA retraction mechanism. As well, containing the propulsion system in the MFA may provide numerous options for easier cooling of the propulsion system components, as the assembly principally only operates when the MFA is submerged in water.

In another aspect, the MFA comprises a cooling aspect, which may be active or passive cooling for the battery, motor controller, motor, or any combination of these elements. In one embodiment, a passive cooling aspect may comprise one or more cooling channels, which are channels within the MFA closed or sealed from the contents of the MFA, and open near the front and rear of the MFA. Such a cooling channel fills with water when the MFA is submerged but is sealed such that no water may enter the interior of the MFA. As the channel is open at both ends, forward or reverse motion through the water forces the water through the channel. The surface of the channel is formed of heat-conductive material, such that the water moving through the channel conductively cools the material. Within the MFA, elements which may require cooling may be connected conductively to the surface of the channel, allowing those elements to be cooled by the water moving through the channel.

In one embodiment, the MFA may be formed with a central cooling channel, with elements to be cooled located in watertight containers mounted to the wall of the channel, within the stream of the water.

In one embodiment, passive cooling may be achieved by constructing the MFA from a mesh or grill material, such that the water into which the MFA is submerged may flow through the MFA, with elements to be cooled designed to be watertight or placed within watertight and heat-conductive enclosures.

In one embodiment, a passive cooling aspect may comprise a heat-conductive plate, affixed into the exterior wall of the MFA. The MFA's exterior wall may have a hole or cavity which is filled by the conductive plate, with the plate's edge sealed such that the MFA remains watertight. The first side of the conductive plate is therefore exposed exterior to the MFA, while the second side of the plate is within the interior of the MFA. The first, exterior side of the plate is in contact with the water, which provides conductive cooling to the plate. Within the MFA, elements which may require cooling may be connected conductively to the plate, allowing those elements to be cooled by the water in which the MFA is submerged.

In one embodiment, an active cooling aspect may comprise any of the aforementioned passive cooling embodiments with the addition of a pump or propeller which is configured to cause water flow through a channel or past any element or plate which is conductively cooled.

In one embodiment, an active cooling aspect may comprise a closed-loop fluid or air-based cooling system.

In one embodiment, the watercraft may be configured with five independently controlled surfaces: a left aileron, right aileron, elevator, front rudder, and rear rudder. Along with the motor thrust, the navigation system can exert forces and moments in all 6 degrees of motional freedom. This is advantageous over a traditional single rudder, elevator, and combined aileron (3-surface) system which does not inherently allow a watercraft to translate vertically or horizontally without changing orientation since only 4 degrees of motional freedom can be controlled at any moment. A 5-surface system allows for the watercraft to move laterally and vertically at high speeds, and for increased maneuverability at low speeds. Such a system can reject disturbances from wind, current and waves better than a system with 4 degrees of freedom. The system can reject disturbances quickly before they significantly accelerate the watercraft. Ride comfort is also improved through the reduction or elimination of wave and current disturbances.

RSA-Based Watercraft Embodiment

In one embodiment, the watercraft may be configured with a left aileron and right aileron formed as moveable aspects of the main (front) hydrofoil, along with an elevator formed as part of a rear foil.

In this embodiment, the main hydrofoil is attached to at least one front strut, which strut is preferably attached to the hull of the watercraft via a rotating joint. Preferably, the main hydrofoil is fixedly attached to two front struts which are attached to the hull of the watercraft via rotating joints. The trailing edge of the main hydrofoil preferably comprises two ailerons. When deployment of the foil is desired, an actuator causes the struts and foil to swing down below the hull, rotating out from the hull on the rotating joint. When retraction of the foil is desired, an actuator causes the struts and foil to swing up and retract into slots in the aft quarter of the hull. The actuator provides sufficient force to keep the foil deployed or retracted. Preferably, each strut is attached to an actuator.

Optionally, a shear pin may be employed in the rotating joint to lock the joint into a deployed position. The shear pin would provide a strong holding force during normal operation but would shear upon an impact between an obstacle and the hydrofoil or a hydrofoil strut. Upon shearing, the shear pin would no longer hold the foil in place, and the foil would swing back towards the retracted position, limiting the damage caused by the collision.

Optionally, a spring-loaded ball and detent mechanism may be used to hold the struts in place under typical operating loads. Under higher loads, such as those caused by impact with an obstacle, the spring would be compressed, releasing the strut and foil mechanism to pivot back toward the retracted position while minimizing damage to the front foil and struts.

Optionally, a compliant actuator, or an assembly comprising an operational actuator and a rapid retraction actuator, may be used to deploy and retract the hydrofoil. Such an actuator assembly would supply sufficient force to hold the struts in place under typical loads during normal use, but would release under a higher impact load, allowing the foil assembly to swing back towards the retracted position, thereby limiting the damage caused by the collision. Optionally, the actuator or actuator assembly may sense the spike in load caused by the impact and rapidly retract the hydrofoil to limit the damage.

Optionally, a single actuator or actuator assembly may be used to deploy and retract multiple struts simultaneously, rather than an actuator or actuator assembly for each strut.

The elevator is preferably two jointly controlled surfaces on the rear foil but may be a single controlled surface. Preferably, the rear foil is fixedly mounted to a rear strut, to which strut areis also mounted a motor assembly and a propeller assembly. Preferably, the rear strut is shaped to act as a rudder. Preferably, the rear strut is mounted to the watercraft in such a manner to allow the strut to rotate about its long axis, and to raise and lower (translate) along its long axis. Thus, a rear strut assembly (RSA) comprises the rear strut, the rear foil, the motor assembly, the propeller assembly and preferably the elevator formed as part of the rear foil.

The RSA may be raised in shallow water and may be lowered when in deeper water. It is advantageous to lower the RSA even in shallow water when the watercraft is foiling, to allow the foil to be fully immersed in the water during foiling.

The elevators may be controlled by a push rod in the rear strut, which push rod is preferably blended into the shape of the rear strut, but which may be housed internal to the rear strut.

Surfaces

Regardless of the number of controlled surfaces, the control surfaces may be pivoted near the first end of the surface proximal to the front of the watercraft, or at some other pivot point along the surface. Preferably the surfaces are pivoted near the centre of lift of the surface, to reduce the force needed to turn them.

In another aspect, the foils may be designed in a swept-back plan, to allow weeds or other objects in the water to slide toward the outer edges of the foils and be swept off by the water current. In another aspect, the foils may incorporate a sharp leading edge that may cut through weeds or other objects in the water.

In another aspect, the length of the front foil strut from the watercraft's hull to the foil may be determined by calculating the watercraft's desired maximum bank angle while foiling, such that the edges of the foil remain submerged when the watercraft is banked at this angle. Preferably, the maximum bank angle is between 30 and 40 degrees from vertical.

In another aspect, the watercraft may be equipped with a watercraft control system (or “WCS”) which provides one or more of these aspects, which may be combined and run concurrently:

- Optimized roll control, which allows the watercraft to turn with reduced roll while foiling, to maximize how much the hydrofoil's surface stays below the water level.
- Dual rudder control, which when rotating the forward and rear rudders in the same direction allows independent control of the watercraft speed in the transverse as well as longitudinal axes. This allows for course corrections to compensate for drift due to wind and current without changing the boat's heading. When rotating the forward and rear rudders in opposite directions, a tighter turning radius can be achieved than with a single rudder, increasing maneuverability particularly when operating at low speed.
- Smart Piloting mode: In this mode, the control system balances various competing variables as specified by the user, or as inferred from the user's interactions with the system. In one aspect, the user may specify a prioritization of factors such as battery life, maximum forward speed, maximum acceleration or some combination of these, and the system will balance foiling height and speed to deliver the desired balance of the factors. In one aspect, the user may be presented with a number of predetermined user performance settings (such as “performance”, “economy”, “balanced”) which each correspond to a different relative balancing of factors, and upon the user selecting one of these modes, the system will balance foiling height and speed to deliver the desired performance.
- Remote control mode: In this mode, the on-board controls of the watercraft may optionally be deactivated, and the steering and propulsion systems are controlled remotely from an external controller, which controller may be one or more of a phone, tablet, remote controller or a controller mounted to a tow rope extending from the watercraft. In another embodiment, the on-board controls may still be active while being viewable or controllable from the external controller.
- Autonomous mapping mode: In this mode, the watercraft autonomously navigates around a body of water to build a map of the lake, including water depth. Optionally, this mapping may be performed at a slow, safe speed. The map thusly constructed may be sent to a server to be combined with other maps or navigational aids to create a composite map of the body of water. The map or composite map may be used by the watercraft to determine areas in which it is safe to deploy the hydrofoil, ensuring that the watercraft stays in water deep enough for foil deployment while operating at high speed. The map may be used to plot optimal courses through the body of water, where an optimal course is determined by various estimated factors including power consumption, top speed, average speed, time spent with the hydrofoil deployed, or any other factor which may be desirable. Such optimal courses may be displayed to the pilot via a user interface.
- Health emergency mode: In this mode, upon detection of an appropriate emergency condition, such as a rider falling overboard or the pilot becoming incapacitated, the watercraft stops its current action and reduces motor speed. Preferably, if the emergency is a rider falling overboard, the watercraft returns to an estimated or detected location of a rider who may have fallen overboard.
- Virtual anchor mode: In this mode, a specific location is provided to the WCS, and the WCS causes the watercraft to remain in that location. The location may be provided as coordinates. The WCS may cause the watercraft to move forward or in reverse and may use a dual rudder system to cause the watercraft to move laterally. The WCS may be configured to remain in an anchor zone instead of a single location, in which case the WCS may cause the watercraft to remain within the anchor zone. If an anchor zone is employed, the WCS may track the unpowered drift of the watercraft and, upon the watercraft moving to the edge of the anchor zone, reposition the watercraft such that a maximum amount of drifting time may pass before a repositioning is required again.
- Valet mode: In this mode, restrictions are placed on the control of the watercraft such that a maximum forward speed, a maximum forward acceleration, a maximum turning angle (or equivalently, a minimum turning radius), a maximum distance from a specified location, a maximum motor power output or a maximum roll angle may be specified. Such a mode may allow the activation of onboard sensors or cameras for remote monitoring. Such a mode may allow the restriction of the deployment of any hydrofoil on the watercraft. Such a mode may allow for any operator-specific or passenger-specific performance or geo-fencing limitation. In another aspect, the mode may allow for a geo-fence to be specified, preferably via a smartphone or tablet, and the mode causes the watercraft not to move outside of the geo-fence by slowing and stopping the watercraft as the boundary of the geo-fence is approached, and preferably actively steering the watercraft in such a way as to avoid moving outside of the geo-fence, and preferably returning the watercraft to within the geo-fence if the watercraft has drifted out of or otherwise left the geo-fenced area.
- Self-piloting mode: In this mode, the watercraft may follow a programmed route while using sensors to avoid obstacles. Sensors, electronic maps and other navigational information may be used to determine minimum or maximum speeds to maintain over segments of the route. “Avoid zones” may be specified, which, should the programmed route pass through such a zone, will cause the WCS to pilot the watercraft around the avoid zone and rejoin the programmed route at a later point. An extension of this mode, Ferry/Tender Mode, would allow for a programmed route to be repeated with each repetition beginning after a predetermined wait time or upon a trigger condition being sensed, such a trigger condition comprising one or more of a user interface interaction either on the watercraft's user interface or on an associated smartphone or tablet, a visual sensing of the watercraft being in departure-ready condition, a weight sensing of passengers entering or leaving the watercraft, any information from a sensor, or any calculated information based on sensor or other data.
- Limp-home mode: In this mode, the watercraft's guidance system maintains knowledge of a route back to a home or safe location. Preferably, the energy needed to move the watercraft from its current position at any time to the home location is regularly recalculated, and when the available battery energy drops to within a specified range of this required energy, an alert is presented to the pilot. Optionally, a setting may be set within the guidance system such that when the battery energy drops to within a specified range of this required energy, the watercraft automatically pilots itself back to the home location. In another aspect, the system may present a user interface to the user showing a map of the surroundings and an indication of how far the watercraft may travel before running out of energy. In another aspect, the system may present a user interface to the user showing a map of the surroundings and an indication of how far the watercraft may travel before no longer having enough energy to return to the home location.
- External connection mode: In this mode, the guidance and control system are connected to the internet and preferably cloud infrastructure through a satellite connection on the watercraft or through an internet-connected cell phone or tablet which acts as an intermediary. In one aspect, the connection to a cell phone or tablet enables the user of the phone/tablet to activate, control and synchronize under-surface lights on the watercraft, which synchronization is between the colors or brightness of the lights with music or audio playing from the phone/tablet. In one aspect, the guidance and control system may be enabled to share information about the watercraft to a cloud server or through a social media application, which information may include one or more of the watercraft's location, the watercraft's heading, the watercraft's route, the watercraft's speed, the watercraft's list of the passengers, a video or audio feed from the watercraft, or any other information available to the guidance and control system.
- Pilot Assistance: In this mode, the guidance system assists the pilot in at least one of several ways. In one aspect, if a cruise control is enabled, the guidance system maintains the current heading and speed of the watercraft. Preferably, when cruise control is enabled, the watercraft detects and avoids obstacles. In one aspect, the system displays, or causes to be displayed on a connected smartphone or tablet, a map of the surroundings and preferably indicates at least one of the directions back to a specified home location and the route back to a specified home location. In one aspect, the system may enable a night mode to assist the pilot in navigation in the dark, such a mode preferably comprising presenting the pilot with a map readable in the dark, providing earlier alerts about potential obstacles, upcoming turns or points of interest, and using any available watercraft-mounted lights to highlight nearby obstacles or points of interest. In one aspect, the system may plot an optimal course to a desired location through the body of water, where an optimal course is determined by various estimated factors including power consumption, top speed, average speed, time spent with the hydrofoil deployed, or any other factor which may be desirable. Such an optimal course may be displayed to the pilot via a user interface.
- Assisted docking/Assisted trailering modes: In these modes, the WCS may align the watercraft for docking or trailering, may indicate preferred motions or controls or feedback to the user during docking or trailering, may maneuver the watercraft to the dock or onto the trailer, may allow for remote piloting of the watercraft with a user interface intended for docking or trailering operations (for instance, with the scales of the controls modified to provide small changes in operation with larger changes in control motions, effectively “gearing down” the controls for close-in maneuvering), may present in a user interface a generated “top-down” overhead view of the watercraft overlaid onto a map, may present information to the user from any proximity, sonar or other sensors mounted on the side of the watercraft, or any combination of these. These modes may be aided by active or passive fiducial markers, beacons, GPS receivers, or some other active or passive system configured to aid in autonomous or semi-autonomous docking or trailering.
- Steering wheel-based foiling controls: The watercraft may be equipped with controls to adjust desired forward speed and desired foiling height, which height may be defined as the height of the watercraft's hull from the surface of the water
- Sentry Mode: In this mode, the watercraft may be equipped with cameras and microphones whose video and audio may be accessed remotely when the watercraft is moored or stored. Preferably, the system would automatically detect and notify the user of motion or unexpected activity around or in the watercraft.
- Follow Mode: In this mode, the user may specify to the WCS, via a user interface, the identity or location of another target watercraft to follow, and the control system will pilot the watercraft in such a way as to safely maintain a specified distance between itself and the target watercraft.

In another aspect, a waterfront dock is provided at which the watercraft may be docked. In one embodiment, the dock comprises a charging interface to the watercraft, a battery and a slow-charge interface. The slow-charge interface may be connected to a standard household outlet, a high-voltage residential circuit, a 3-phase residential or commercial circuit, a solar panel array, a fuel-powered generator, a hydroelectric generator, or any other source or combination of sources of electric power, from which the battery may be charged. The charging interface to the watercraft provides a high-powered, fast electric charging interface to the watercraft. In one embodiment, the dock comprises a passive or active fiducial marker, a beacon, a GPS receiver, or some other passive or active system configured to aid in autonomous or semi-autonomous docking.

In another aspect, a sensor may be mounted at the front of the MFA, on the front hydrofoil, on one or more front struts or onto the hull of the watercraft, to detect upcoming shallow water, rocks, obstacles substantially under the water, obstacles near the surface of the water and obstacles floating on the water. Preferably, the sensor is a forward- and downward-facing scanning sonar module. To avoid obstacles, the watercraft may initiate one or more avoidance maneuvers, such as tilting the watercraft, swerving, accelerating, ascending to bring the bottom of the MFA close to the surface of the water, or rapidly ascending to cause the watercraft to break the surface and jump over the obstacle. Preferably, the watercraft may be enabled to warn the pilot of a possible collision or to retract the hydrofoil before a collision. The sensor is preferably enabled to detect weeds in the water. With such detection, or with any other weed detection system, the watercraft may be enabled to avoid deploying the hydrofoil in the presence of weeds. The sensor is preferably enabled to detect water depth that is too shallow for deployment or use of the hydrofoil. With such detection, the watercraft may be enabled to avoid deploying the hydrofoil in water that is too shallow.

Detection of nearby rocks or other watercraft may also be performed by using cameras mounted on the watercraft to detect nearby obstacles, or by monitoring radio frequencies known to be used by watercraft or passengers (such as BlueTooth®) and sensing the strength, change in strength over time, direction, change in direction over time, or some other aspect of the signal and calculating the likely location of the generator of the signal, and alerting the pilot if the rocks, watercraft or generators of the radio signals are likely to pose a hazard to the watercraft, and preferably taking avoidance actions if the rocks, watercraft or generators of the radio signals are likely to pose a hazard to the watercraft. If another watercraft is detected in proximity of the watercraft, the control system may be enabled to identify the type of the other watercraft based on sensor information or camera-based visual identification such as recognizing the other watercraft's registration number, looking up the registration number in a database and correlating it to the type of watercraft. If another watercraft is detected in proximity of the user's watercraft, the control system may be enabled to detect the direction and speed of the other watercraft's motion, to analyze whether the other watercraft poses a hazard to the user's watercraft, and if so, to alert the pilot to the hazard and optionally take avoidance actions.

The sensor, or an additional sensor, may be used to detect fish in the water around the watercraft. A user interface presented through computing hardware on the boat or preferably through a smartphone or tablet may show the presence of fish in the water around the watercraft. Optionally, the control system may be directed to move the watercraft in the direction of fish.

Through the use of a camera system mounted to the watercraft and a user interface, the control system may be enabled to identify, decode and explain to the pilot or passengers the meaning of naval signs, beacons and buoys, and may alert the pilot to actions which must be legally taken based on the presence of a naval sign, beacon or buoy. Preferably, the system requires an explicit override from the pilot in order to contravene maritime law associated with a naval sign, beacon or buoy which the system detects.

In one embodiment, the propulsion system in the MFA or RSA may comprise a water jet assembly in place of the propeller, to enclose the blades for increased safety of the operator, swimmers, water skiers and marine wildlife.

In one embodiment, the thrust of the propeller or water jet may be directed by changing the orientation of the propeller shaft or water jet assembly, or by incorporating moveable vanes in the water flow behind the propeller or water jet, in order to increase maneuverability.

In one embodiment, side thrusters may be incorporated into the at least one of the vertical struts which may form part of the rudder assemblies, into the MFA, or into the RSA. Such side thrusters allow for lateral maneuverability at low speeds, when the rudders may not be as effective.

In one embodiment, the length of at least one hydrofoil, as measured from where each hydrofoil is attached to the central propulsion assembly, or the chords of the foil, may be dynamically modified, effectively changing the surface area of each foil. The area of each foil may be varied with the speed of the watercraft, the weight distribution of the load on the watercraft, or any other factor. At higher speeds, less lift is needed from each foil; reducing the surface area of each foil reduces the drag caused by the foil while still providing the needed lift at that speed. In one embodiment, the extension or retraction of each foil may be accomplished by configuring the foil in two nesting parts, with one part nesting into the other part when actuated by a motor or pneumatic or hydraulic cylinder.

FIGS. 1-4 are diagrams comprising multiple views of an embodiment of an MFA-based watercraft. According to this disclosure, FIG. 1 is a diagram illustrating a left side view of a watercraft 100. FIG. 2 is a diagram illustrating a front plan view of a watercraft 100. FIG. 3 is a diagram illustrating a bottom plan view of a watercraft 100. FIG. 4 is a diagram illustrating a perspective view of a watercraft 100.

The MFA 105 is shown suspended below the hull of the watercraft. In this embodiment, as well as the embodiments discussed below, the MFA 105 comprises a front rudder assembly 110, a rear rudder assembly 115, a central propulsion assembly 120 attached fixedly to the front and rear rudder assemblies and comprising a battery contained within the central propulsion assembly 120, a motor controller contained within the central propulsion assembly 120, a motor contained within the central propulsion assembly 120 and a propeller 140, a left (or port) hydrofoil assembly 145 attached fixedly to the central propulsion assembly 120 and comprising a left (or port) aileron assembly 150, a right (or starboard) hydrofoil assembly 155 attached fixedly to the central propulsion assembly 120 and comprising a right (or starboard) aileron assembly 160, a left (or port) elevator assembly 165 attached rotatably to the rear rudder assembly 115 or to the central propulsion assembly 120, and a right (or starboard) elevator assembly 170 attached rotatably to the rear rudder assembly 115 or to the central propulsion assembly 120.

FIG. 5 is a schematic diagram of the electronic, power and navigational hardware of an embodiment of the watercraft. The central Pixhawk® 4 processor 510 may be any processor or embedded controller with appropriate interfacing and processing capabilities. In one embodiment, the elements located within the bottom oval 520 are situated within the propulsion assembly in the MFA, while the other elements are situated within the hull of the watercraft or connecting from the hull to the MFA.

FIGS. 6-8 are diagrams comprising multiple views of an embodiment of an MFA-based watercraft, with an offset-V foil retraction mechanism. According to this disclosure, FIG. 6 is a diagram illustrating a front plan view of a watercraft. FIG. 7 is a diagram illustrating a left plan view of a watercraft. FIG. 8 is a diagram illustrating a perspective view of a watercraft.

In this embodiment, as shown in FIGS. 6-8, the retraction mechanism may comprise two sliding support arms 605, 610 at the front of the MFA 105 and a single sliding support arm 615 at the rear of the MFA 105, in an offset-V configuration. When the MFA 105 is deployed, the front arms are configured in a “V” shape when viewed from the front of the watercraft, as well as when viewed from the side. The support arms are rotatably coupled to the MFA 105, and during retraction or deployment slide forward or backward along tracks on the underside of the watercraft 100.

FIGS. 9-11 are diagrams comprising multiple views of an embodiment of an MFA-based watercraft, with an inline-V foil retraction mechanism. According to this disclosure, FIG. 9 is a diagram illustrating a front plan view of a watercraft. FIG. 10 is a diagram illustrating a left plan view of a watercraft. FIG. 11 is a diagram illustrating a perspective view of a watercraft.

In this embodiment, as shown in FIGS. 9-11, the retraction mechanism may comprise two in-line sliding support arms 905, 910 at the front of the MFA 105 and a single sliding support arm 915 at the rear of the MFA 105, in an inline-V configuration. When the MFA 105 is deployed, the front arms 905, 910 are configured to be substantially in-line with one another when viewed from the front of the watercraft 100 and form a “V” shape when viewed from the side. The support arms are rotatably coupled to the MFA 105, and during retraction or deployment slide forward or backward along tracks on the underside of the watercraft.

FIGS. 12-14 are diagrams comprising multiple views of an embodiment of an MFA-based watercraft, with a swing-up foil retraction mechanism. According to this disclosure, FIG. 12 is a diagram illustrating a front plan view of a watercraft. FIG. 13 is a diagram illustrating a left plan view of a watercraft. FIG. 14 is a diagram illustrating a perspective view of a watercraft.

In this embodiment, as shown in FIGS. 12-14, the retraction mechanism may comprise one arm 1205 at the front of the MFA 105 and one arm 1210 at the rear of the MFA 105. Both arms are rotatably coupled to the MFA at their first ends 1215, 1220, and rotatably coupled to the watercraft at their second ends 1225, 1230. During retraction or deployment, the arms 1205, 1210 swing up or down from the watercraft, causing the MFA 105 to retract or deploy. Retraction or deployment may be actuated through a motor coupled to the second end of one arm, through motors coupled to the second ends of both arms, through a telescoping hydraulic or pneumatic cylinder 1235 coupled to one arm as shown in the Figures, or through some other means.

In one embodiment, a variant of the embodiment shown in FIGS. 12-14, the retraction mechanism may comprise two parallel arms at the front of the MFA and two parallel arms at the rear of the MFA. All four arms are rotatably coupled to the MFA at their first ends, and rotatably coupled to the watercraft at their second ends. During retraction or deployment, the arms swing up or down from the watercraft, causing the MFA to retract or deploy.

FIGS. 15-18 are diagrams comprising multiple views of an embodiment of an RSA-based watercraft. According to this disclosure, FIG. 15 is a diagram illustrating a left side view of an RSA-based watercraft with a double-strut front foil. FIG. 16 is a diagram illustrating a perspective view of an RSA-based watercraft with a double-strut front foil, viewed from above, behind and to the left (port) of the watercraft. FIG. 17 is a diagram illustrating a perspective view of an RSA-based watercraft with a double-strut front foil, viewed from above, ahead of and to the left (port) of the watercraft. FIG. 18 is a diagram illustrating a perspective view of an RSA-based watercraft with a double-strut front foil, viewed from below, ahead of and to the right (starboard) of the watercraft.

In this embodiment, as shown in FIGS. 15-18, the rear strut assembly (RSA) 1505 comprises the rear strut 1510, the rear hydrofoil 1515, the drive motor assembly 1520, the propeller assembly 1525 and preferably the elevator 1530 formed as part of the rear hydrofoil 1515. The front strut assembly (FSA) 1535 comprises left (or port) 1540 and right (or starboard) front struts 1545, the front hydrofoil 1550, a left (or port) aileron 1555, a right (or starboard) aileron 1560, a left rotating joint 1565 attaching the left front strut 1540 to the hull 1570 of the watercraft, and a right rotating joint (not shown) attaching the right front strut to the hull of the watercraft. The hull 1570 comprises a left strut slot 1575, a right strut slot 1580 and a hydrofoil slot 1585, into which fit the left front strut 1540, the right front strut 1545 and the front hydrofoil 1550, respectively, when the front strut assembly 1535 is retracted. A hydraulic or electric linear actuator 1590, preferably connected rotatably to a front strut 1545 via a lever arm 1595, causes the strut to rotate about the rotating joint in order to deploy or retract the front hydrofoil. Preferably, each front strut is connected to its own actuator by its own lever arm.

Preferably, the FSA is located near to the fore-aft center of gravity of the watercraft.

In one embodiment, the left front strut 1540 and right front strut 1545 may have rudders formed on their trailing edges, such rudders being individually controllable by the control system.

FIG. 19 is a diagram illustrating a perspective view of a watercraft steering wheel. The steering wheel 1905 is mounted rotatably into the console, and configured to cause the watercraft 100, in operation, to turn when the steering wheel is turned. Preferably, the steering wheel is configured to send a signal to the guidance and control system 1910 when it is turned, or to signal its rotational position regularly to the guidance and control system. Optionally, the steering wheel may be mechanically or electrically connected to a rudder or to a drive motor direction control assembly.

A height control 1915 and a speed control 1920 are mounted movably to the console. Preferably, these controls are mounted to the steering wheel 1905. Preferably, these controls are embodied as slider controls mounted to the steering wheel. Optionally, these controls may be embodied as rollers, fixed up/down switches or some other controls. The height control is preferably configured to send a signal to the guidance and control system 1910, to indicate to that system how high above the surface of the water it is desired for the watercraft to ride. The speed control is preferably configured to send a signal to the guidance and control system 1910, to indicate to that system how fast it is desired for the watercraft to move in the direction of travel.

The guidance and control system are preferably housed in a waterproof case 1925 in an accessible location. In this embodiment, the system is shown mounted ahead of the steering wheel but may be located elsewhere in the watercraft.

FIGS. 20-22 are diagrams comprising multiple views of elements of the rear strut assembly (RSA). FIG. 20 is a diagram illustrating a perspective view of the drivetrain and RSA of an RSA-based watercraft. FIG. 21 is a diagram illustrating a perspective view of the lower section of an RSA of an RSA-based watercraft, viewed from above the rear foil. FIG. 22 is a diagram illustrating a perspective view of the lower section of an RSA of an RSA-based watercraft, viewed from below the rear foil.

Referring to FIGS. 20-22, a top case 2005 houses and protects the drive motor (not shown-contained within the top case), drive motor controller (not shown-contained within the top case) and cooling units (not shown-contained within the top case). A lower unit 2010 comprises an internal gearbox (not shown), a propeller plate 2015 on the back of the lower unit, and a propeller (not shown) attached to the propeller plate. The rear strut 1510 preferably comprises an actuator arm 2020, which arm is formed on the trailing edge of the rear strut, is attached movably to an elevator actuator 2025 at its first end and to the elevator 1530 at its second end, and which slides vertically to actuate the elevator control surface. Optionally, the elevator actuator arm may be housed within the rear strut instead of being formed as part of the trailing edge of the rear strut. A rear foil 1515 is mounted fixedly to the rear strut, and comprises an elevator control surface 1530, which is formed as part of the trailing edge of the rear foil. Preferably, an anti-ventilation plate 2030 is attached to the rear strut 1510, above and substantially parallel to the rear foil 1515. The anti-ventilation plate improves the efficiency of the drive motor by preventing surface air from being pulled into the negative pressure side of a propeller.

FIGS. 23-25 are diagrams comprising multiple views of the interior of an RSA-based watercraft. FIG. 23 is a diagram illustrating a section of an RSA-based watercraft. FIG. 24 is a diagram illustrating a cut-away perspective view of an RSA-based watercraft. FIG. 25 is a diagram illustrating a perspective view of the front foil actuator of an RSA-based watercraft.

Referring to FIGS. 23-25, the pilot's seat 2305 and battery modules 2310 are located near to the fore-aft center of gravity of the watercraft 100. Preferably, the battery modules are located low in the watercraft to keep the center of gravity of the watercraft low. Preferably, the battery modules are wired in series (to provide higher output voltage) or parallel (to provide higher amp-hour capacity) and sized such that each battery may be easily carried by a person. Each battery module may comprise one or more of a battery monitor system (internal to the module, not shown here), a temperature control heating and cooling system (internal to the module, not shown here), and a waterproof casing (not shown). Each battery module may include an interface to communicate the battery status and configuration with the WCS, in order to enable and configure charge and discharge rates. Optionally, a single interface may communicate the battery status and configuration from multiple battery modules to the WCS.

The watercraft hull 1570 comprises a left strut slot (shown in previous figures), a right strut slot (shown in previous figures) and a hydrofoil slot 1585, into which fit the left front strut (shown in previous figures), the right front strut 1545 and the front hydrofoil 1550, respectively, when the front strut assembly 1535 is retracted. A hydraulic or electric linear actuator 1590, preferably connected rotatably to a front strut 1545 via a lever arm 1595, causes the strut to rotate about the rotating joint 2315 in order to deploy or retract the front hydrofoil. Preferably, each front strut is connected to its own actuator by its own lever arm. An electric servo motor 2320 drives the motion of a push-rod 2322, which in turn drives rotation of an inner shaft 2325 within the rotating joint 2315 via an aileron actuation pivot arm 2327. A push-rod within the strut 1545 is connected at the first end to the inner shaft 2325 of the rotating joint and at its second end to an aileron 1560, in order to actuate and control the motion of the aileron.

FIGS. 26-27 are diagrams comprising multiple views of the front foil of an RSA-based watercraft. FIG. 26 is a diagram illustrating a perspective view of the front foil of an RSA-based watercraft, viewed from behind the front foil. FIG. 27 is a diagram illustrating a perspective view of the front foil of an RSA-based watercraft, viewed from ahead of the front foil.

Referring to FIGS. 26-27, the main front foil 1550 is preferably formed as a single continuous element, attached fixedly to the bottom of the two front struts 1540, 1545, and comprises at least two ailerons 1555, 1560 on the trailing edges. Preferably the ailerons are formed on the sections of the foil outboard from the struts. Preferably, the section of the foil between the struts is a single piece with no control surfaces. Optionally, this section of the foil between the main struts may include a control surface to vary the lift and drag profile of the front foil. Pockets 2605 are included in the struts to accommodate sensors such as pressure sensors and pitot tubes, which may be used to measure depth and speed of the foil.

FIG. 28 is a diagram illustrating a perspective view of a steering actuator of an RSA-based watercraft. Referring to FIG. 28, a hydraulic or linear electric actuator 2805 is attached movably to the drive motor and rear strut assembly (RSA) 1505, such that the actuator can raise or lower the drive motor and RSA vertically. In shallow water, the RSA may be raised, while in foiling operation, the RSA may be lowered. An electric servo motor 2810 is connected to a gear mechanism 2815 which is in turn connected to the drive motor and RSA 1505 such that operation of the servo motor causes the RSA to turn, to steer the watercraft.

In one embodiment, a two-stage steering mechanism may be employed wherein a larger actuator or motor is used for rapid, user-initiated steering changes while a smaller motor is used for fine course corrections. In such an embodiment, the larger motor may turn an assembly, directly or via a gear mechanism, which assembly comprises the smaller motor and the drive motor, which smaller motor in turn is enabled to rotate the drive motor and RSA.

According to embodiments of this disclosure, a watercraft is disclosed. The watercraft comprises a main hydrofoil and at least one retractable strut wherein the main hydrofoil is attached fixedly to the at least one retractable strut, whereby at least one strut retracts through the action of an actuator. The watercraft further comprises a rotational joint, wherein the at least one strut is rotatably attached to the rotational joint at its first end and attached fixedly to the main hydrofoil at its second end.

According to the disclosure, the watercraft further comprises a shear pin, wherein the strut is held in its deployed state by the shear pin. The watercraft further comprises a compliant actuator, wherein the strut is held in its deployed state by the compliant actuator. Furthermore, the main hydrofoil of the watercraft further comprises at least one aileron mounted rotatably on the trailing edge of the main hydrofoil.

According to the disclosure, the watercraft further comprises a rear strut, a rear hydrofoil and an elevator, wherein the rear strut is rotatably and retractably attached to the watercraft, the rear hydrofoil is fixedly attached to the rear strut, and the rear hydrofoil comprises an elevator mounted rotatably on the trailing edge of the main hydrofoil. The strut further comprises a push-rod aileron actuator formed movably on the trailing edge of the strut, wherein the push-rod aileron actuator is movably attached at its first end to the at least one aileron.

Implementations disclosed herein provide systems, methods and apparatus for generating or augmenting training data sets for machine learning training. The functions described herein may be stored as one or more instructions on a processor-readable or computer-readable medium. The term “computer-readable medium” refers to any available medium that can be accessed by a computer or processor. By way of example, and not limitation, such a medium may comprise RAM, ROM, EEPROM, flash memory, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer. It should be noted that a computer-readable medium may be tangible and non-transitory. As used herein, the term “code” may refer to software, instructions, code or data that is/are executable by a computing device or processor. A “module” can be considered as a processor executing computer-readable code.

A processor as described herein can be a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor can be a microprocessor, but in the alternative, the processor can be a controller, or microcontroller, combinations of the same, or the like. A processor can also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. Although described herein primarily with respect to digital technology, a processor may also include primarily analog components. For example, any of the signal processing algorithms described herein may be implemented in analog circuitry. In some embodiments, a processor can be a graphics processing unit (GPU). The parallel processing capabilities of GPUs can reduce the amount of time for training and using neural networks (and other machine learning models) compared to central processing units (CPUs). In some embodiments, a processor can be an ASIC including dedicated machine learning circuitry custom-build for one or both of model training and model inference.

The disclosed or illustrated tasks can be distributed across multiple processors or computing devices of a computer system, including computing devices that are geographically distributed. The methods disclosed herein comprise one or more steps or actions for achieving the described method. The method steps and/or actions may be interchanged with one another without departing from the scope of the claims. In other words, unless a specific order of steps or actions is required for proper operation of the method that is being described, the order and/or use of specific steps and/or actions may be modified without departing from the scope of the claims.

As used herein, the term “plurality” denotes two or more. For example, a plurality of components indicates two or more components. The term “determining” encompasses a wide variety of actions and, therefore, “determining” can include calculating, computing, processing, deriving, investigating, looking up (e.g., looking up in a table, a database or another data structure), ascertaining and the like. Also, “determining” can include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory) and the like. Also, “determining” can include resolving, selecting, choosing, establishing and the like.

The phrase “based on” does not mean “based only on.” unless expressly specified otherwise. In other words, the phrase “based on” describes both “based only on” and “based at least on.” While the foregoing written description of the system enables one of ordinary skill to make and use what is considered presently to be the best mode thereof, those of ordinary skill will understand and appreciate the existence of variations, combinations, and equivalents of the specific embodiment, method, and examples herein. The system should therefore not be limited by the above-described embodiment, method, and examples, but by all embodiments and methods within the scope and spirit of the system. Thus, the present disclosure is not intended to be limited to the implementations shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

ELECTRIC-POWERED BOAT WITH RETRACTABLE HYDROFOIL

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