US20220227468A1

US20220227468A1 - Kite power with directional control for marine vessels

Info

Publication number: US20220227468A1
Application number: US17/578,906
Authority: US
Inventors: Robert Richardson; Gregory Hall
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-01-19
Filing date: 2022-01-19
Publication date: 2022-07-21
Also published as: WO2023146775A1

Abstract

The disclosure provides methods and devices for enabling a Vessel propelled by a Kite or similar devices, e.g., a balloon, to adjust its direction of travel to either side of the true wind direction without the aid of rudder(s), tiller(s), or similar devices. The subject invention applies to wind-powered Vessels as well as hybrid vessels and vessels utilizing propeller-driven propulsion, jot propulsion and others in addition to wind power.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority under 35 U.S.C. 119(e) to U.S. Provisional Patent Application Ser. No. 63/138,858, titled: KITE POWER WITH DIRECTIONAL CONTROL FOR MARINE VESSELS, filed on Jan. 19, 2021, the disclosure of which is hereby incorporated by reference in its entirety for all purposes.

FIELD OF THE INVENTION

The disclosure generally relates to marine vessels, and more particularly to optimizing kite power with, directional controls for marine vessels.

BACKGROUND OF THE INVENTION

Air moving with respect to the vessel's position (Wind) has been used as a method of vessel (boat/ship) locomotion (hereinafter referred to as Sailing or Sail) for more than 5,000 years. Sailing technology reportedly originated in or around Mesopotamia or Egypt and is now used around the world. From then until now, the sailing vessels have varied in many ways for example, size, materials of construction and number of hulls. Collectively they are all referred to as Vessels in this document.

SUMMARY OF THE INVENTION

The disclosure provides methods and devices for enabling a Vessel propelled by a Kite or similar devices, e.g., a balloon, to adjust its direction of travel to either side of the true wind direction without the aid of rudder(s), tillers, or similar devices. The subject invention applies to wind-powered Vessels as well as hybrid vessels and vessels utilizing propeller-driven propulsion, jet propulsion and others in addition to wind power. In some embodiments vessel direction of travel can vary to either side of the true wind direction by up to about 90 degrees. A direction of travel is obtained within about +90 /−90-degree deviation from the true wind direction by moving the point of attachment between the Vessel and the surface area(s) intended to interact with Wind. The method reported in this document is uniquely different from essentially every other Sailing Vessel because it does not require the use of a pole or poles affixed to the Vessel on one end, with the other end projected into the sky (Masts) as a means of supporting the surface area intended to interact with the wind (Kite).
Kite propulsion for marine vessels has been explored and published elsewhere. All prior art involves attaching the Kite to the bow/front of the Vessel. The subject invention differs from prior Kite-propelled Vessels by applying the Kite force to the Vessel in a manner that more effectively transfers the force supplied by the interaction between the Kite and wind to the Vessel as will be described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure, in accordance with one or more various embodiments, is described in detail with reference to the following figures. The drawings are provided for purposes of illustration only and merely depict exemplary embodiments of the disclosure. These drawings are provided to facilitate the reader's understanding of the disclosure and should not be considered limiting of the breadth, scope, or applicability of the disclosure. It should be noted that for clarity and ease of illustration these drawings are not necessarily made to scale.

FIG. 1 illustrates an embodiment of a System Control Diagram;

FIG. 2A illustrates an embodiment of a Manual Carriage positioning device;

FIG. 2B illustrates an embodiment of a Cable-driven carriage;

FIG. 2C illustrates an embodiment of a Hydraulic actuator driven carriage;

FIG. 2D illustrates an embodiment of a Chain-driven carriage;

FIG. 3 illustrates an embodiment of the Mechanics of Kites attached to the bow of a vessel;

FIG. 4 illustrates an embodiment of Cancelling lateral effects of Kite force that is not from in front of the vessel;

FIGS. 5A & 5B illustrates an embodiment of the Turning effect caused by longitudinal movement of Kite point of attachment with track mounted at the longitudinal center line of the vessel that intersects the Center of Turning;

FIGS. 6A & 6B illustrates an embodiment of the Turning effect caused by transverse movement of Kite point of attachment that intersects Center of Turning;

FIG. 7A & 7B illustrates an embodiment of the Turning effect caused by Kite connection to Vessel at transverse point of attachment that is stern of the Center of Turning;

FIGS. 8A & 8B illustrates an embodiment of Turning effect caused by variation in angle, Θ with Kite connection to Vessel at a transverse point of attachment that is stern of the Center of Turning;

FIGS. 9A & 9B illustrates an embodiment of Turning effect caused by movement of transverse track position along Vessel Y axis;

FIGS. 10A & 10B illustrates an embodiment of Transversely mounted track in front of the Center of Turning;

FIGS. 11A & 11B illustrates an embodiment of Side-mounted track;

FIG. 12 illustrates an embodiment of Manual transfer of Kite cable from side to side;

FIG. 13 illustrates an embodiment of Continuous side-mounted track;

FIG. 14 illustrates an embodiment of Kite powered jibe turn with continuous side mounted track;

FIG. 15 illustrates an embodiment of Perimeter cable-driven carriage;

FIG. 16 illustrates an embodiment of Hull tilt moment counteracted by Kite steering moment;

FIG. 17A illustrates an embodiment of Kite cable and sensor array with pilot Kite;

FIG. 17B illustrates an embodiment of Exemplary wind sensor;

FIG. 17C illustrates an embodiment of Differential pressure-based wind speed sensor assembly;

FIG. 17D illustrates an embodiment of a Cable mounted sensor with power generation;

FIG. 18 illustrates an embodiment of Tripoidal shaped Kite cable collection device & area changing system;

FIG. 19 illustrates an embodiment of Example of concept for Cable storage device;

FIG. 20 illustrates an embodiment of Examples of Kite designs;

FIG. 21 illustrates an embodiment of an Exemplary 4-cable Kite;

FIG. 22 illustrates an embodiment of Adjusting Kite area by reducing the size of Wind scoop;

FIG. 23 illustrates an embodiment of Adjusting Kite power by changing wind flap opening;

FIG. 24 illustrates an embodiment of a Carriage with motor-driven Kite cable spools; and

FIG. 25 illustrates an embodiment of a Vessel-mounted Kite cable spools for 4-cable Kite.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

The following description is presented to enable a person of ordinary skill in the art to make and use embodiments described herein. Descriptions of specific devices, techniques, and applications are provided only as examples. Various modifications to the examples described herein will be readily apparent to those of ordinary skill in the art, and the general principles defined herein may be applied to other examples and applications without departing from the spirit and scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples described herein and shown but is to be accorded the scope consistent with the claims.
The word “exemplary” is used herein to mean “serving as an example illustration,” Any aspect or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects or designs.
Reference will now be made in detail to aspects of the subject technology, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout.

Method of Vessel Locomotion

The disclosed methodology affixes one or more Kites intended to interact with wind in such a way as to transfer force via one or more cables to a Vessel. The cable(s) connect the Kite to the vessel at one effective location on the Vessel, generating a Kite force vector. With single Kite cable applications, the Kite force vector is in the direction of the kite cable. In multi-kite cable applications, the Kite force vector is in the direction of the sum of each of the individual kite cable vectors. The attachment location of the Kite force vector to the vessel is movable with respect to the Vessel coordinate frame. In one embodiment, the cable connection is located on a mobile carriage with one or more degrees of freedom relative to the Vessel frame of reference (Carriage).
In some embodiments, a single stable Kite is connected to the Vessel via a single cable or rope and is intrinsically stable in flight without the need to adjust cables/ropes affixed to additional points on the Kite. In other embodiments, a Kite is controlled by 2 or 3 or 4 or more cables that can manipulate the orientation, altitude, and power of the Kite. In some embodiments, 2 or more control cables are housed within a common sheath to facilitate cable management at the Carriage. In some embodiments, two or more cables are directed through a common eyelet on the Carriage to precisely locate the application of force. In other embodiments, cables are attached to one or more carriages that are independently mobile and collectively form the Kite force vector attachment point. In all embodiments, the Carriage locates the center of force from the Kite to a specific location with respect to the vessel frame of reference.
in some embodiments, an unstable Kite is utilized with a single cable. This can result in a Kite traversing the sky in a figure-8 pattern. As the Kite travels in this pattern, the Kite force vector acting on the Vessel changes direction. In one embodiment, an automated control system adjusts carriage location to compensate for variation in the Kite force direction to maintain a desired Vessel course.
A Kite control system requires information on the Kite orientation, altitude, and stability in order to adjust and optimize the Kite power. Kite orientation can be discerned by one or more sensors (e.g., accelerometers) mounted on the Kite, measurement of tension in one or more Kite cables, and measurement of. Kite control cable length. Kite altitude can be discerned based on one or a combination of Kite cable length (e.g., amount unspooled), Kite cable angle, line-mounted altitude sensors, Kite-mounted altitude sensors, optical measurement of the distance between photo targets on the kite from a mounted camera, laser, radar, or similar technology, and Kite-mounted GPS. Kite power can be discerned by tension sensors in the cable, tension, sensors in the Kite, load sensors in the Carriage, and/or load sensors in the track to vessel connection.
The connection between the Kite(s) and Vessel is via one or more cables, ropes, or similar devices hereinafter as Cables. In one embodiment, one end of the cable/rope is affixed to the Kite and the other is affixed to a movable piece of hardware (Carriage) that is mechanically connected to a track in such a way that the Carriage is restrained from leaving the surface of the track, is limited to motion along the length of the track and can be restrained at a designated point. The track is typically connected to a fixed location on the vessel, however in some embodiments the track can move as well. The combination of Carriage and Track assembly is referred to as the Track Assembly.
In another embodiment one end of a Cable is affixed to the Kite and the other is affixed to a piece of hardware hereinafter referred to as Coupling that is mechanically connected to two or more Cables that are affixed to the Vessel. The position of the Coupling with respect to the Vessel is moved by adjusting the lengths of one or more of the Cables that connect it to the Vessel.
Increasing the height of Kite attachment above the water line induces list in the Vessel towards the Kite, which could indirectly induce Vessel turning away from the Kite due to reaction forces with the water.
Every Vessel has a center of turning. This point is Vessel-specific and is determined by the physical characteristics of the Vessel. Variables that influence the center of turning include but are not limited to keels, center boards, hydrofoils, center of mass location, hull shape, chines, number of hulls, quantity and location of cargo, and hull shape (e.g., continuously varying curvature). Environmental factors can also influence the center of turning such as water current speed and direction, surface wind speed and direction, vessel speed, and vessel list.
Large commercial Vessels that are essentially a long tube with a bow, rudder(s) and no distinguishing hull characteristics may turn on or near the Vessel center of gravity (CG). However, the CG is not necessarily collocated with the center of turning for all Vessel types. In this document, the Center of Turning (CT) defines the point about which the vessel turns. The center of turning is the location about which a Vessel pivots when all threes and moments acting on the Vessel are considered. The center of turning is not the center of an arc of travel of a Vessel, which is normally located far from the Vessel.
The Track Assembly is attached to the Vessel. There are several possible orientations of the Track Assembly with respect to the Vessels hulks) long axis. In a first embodiment, the Track. Assembly is parallel with the longitudinal axis of the Vessel. In one application of the first embodiment, the Track Assembly intersects the Vessels Center of Turning and continues for some direction either side of the point of intersection.
In a second embodiment, the Track Assembly is perpendicular to the longitudinal axis of the Vessel (i.e. transversely mounted). In the first application of this embodiment, the Track Assembly intersects the Center of Turning and continues beyond it in both directions.
In another application of the second embodiment, the Track Assembly does not intersect the Vessel's Center of Turning but is a small percentage of the Vessels length away from the Center of Turning (fore or aft of the center of turning) and continues for some distance either side (port & starboard) of the proximity to the Center of Turning.
In a third embodiment, a first Track Assembly attaches to a second Track Assembly with, a translating degree of freedom. In one embodiment, the two Track Assemblies are orthogonal and effectively create a Cartesian coordinate system with X and Y degrees of freedom.
In a fourth embodiment, the Track Assembly can be rotated about a vertical (Z) axis of the Vessel to enable the Track Assembly to be oriented in angles from 0° to 180° with respect to the longitudinal axis of the Vessel. In this embodiment, the Carriage location for Kite attachment follows a polar coordinate system whereby the Track Assembly angle and Carriage translational location (radius) defines the attachment location with respect to the Vessel reference frame. In other embodiments, the track sweep angle is from 0° to 360°.
In a fifth embodiment, an assembly of Cables and pulleys are used to locate and secure the location of the Coupling for Kite attachment. In one application of the fifth embodiment, the Cables are attached along the longitudinal axis of the Vessel in order to move the Kite attachment point fore and aft with respect to the center of turning. In another application of the fifth embodiment, the Cables are attached transversely across the width of the Vessel. In one embodiment, Cables connect a Coupling to three or more locations on the Vessel, enabling X, Y, and Z motion of the Kite connection point with respect to the Center of Turning. The Coupling location with respect to the Vessel is controlled by adjusting the length of one or more of the three or more Cables. In one embodiment, the Cables that attach the Coupling are attached coiled on motor-driven reels that are attached to posts that are affixed to the Vessel. In some embodiments, a gear box is utilized to provide mechanical advantage to the reel motor and to mitigate against back-driving of the motor when it is de-powered. Other embodiments utilizes clutches and/or brakes on the reel to control reel rotational motion.
A Cable that affixes the Kite to the Vessel via an attachment to the Carriage or Coupling can be adjusted in length via a winch assembly. Unused cable is housed in a Cable storage device. The cable storage device (e.g., a reel or drum) is located on the carriage in sonic embodiments and remotely in other embodiments. When the cable storage device is independent of the carriage, coordinated motion between the reel and carriage is required to permit independent motion while maintaining a target length extended to the Kite.
The Cable length can be hundreds or thousands of feet in length. Greater Cable length affords the opportunity for the Kite to reach different elevations above sea level and thereby gain access to different Wind speeds and directions relative to the Wind at the water surface. The Cable winch assembly can be in any location on the Vessel provided the Cable is routed through a pulley, block or other device that facilitates connection between the winch and Cable storage device and the Carriage or Coupling.
In one embodiment, Cable(s) used to affix the Kite to the Vessel can include electrical conductors and/or circuitry for power and control appurtenances associated with the Kite and/or devices such as sensors placed along the length of the Cable. In one application power is provided through conductors for wind speed sensors, direction sensors, temperature sensors, and/or pressure sensors and other conductors are used to convey telemetry from the sensors affixed to the Kite(s) or Cable to a Kite operational control center on the Vessel. In another application, power is provided through conductors in or on the Cable for actuators or motors affixed to or near to the Kite(s) to adjust physical characteristics of the Kite(s) and other conductors are used to convey sensor data, and commands to and from sensors/equipment that evaluate a change to the Kite's physical characteristics. The telemetry is sent to a Kite's operational control center on the Vessel and the commands come from the Kite's operational control center.
In another embodiment the telemetry to and from devices placed along the length of the Cable or affixed to the Kite(s) can be transmitted via device that utilizes radio, microwave, or other frequency (wireless) means of transmission. Devices on the Kite(s) or cable can be powered by energy from, for example, a battery, solar or wind turbine.
The position of the Carriage or Kite Connection with respect to the Vessel frame of reference can be identified at any position using automatic or manual devices. In the first embodiment, the location of the Carriage on the track can be determined manually by visually comparing an identifiable mark on the Carriage to a numeric or other scale scribed on the track. In the second embodiment, the Carriage position on the track is sensed by an instrument. For example, a string-potentiometer, optical encoder, pulley rotational potentiometer, pully optical encoder, LVDT, contact switches, stepper motor counter, or other typical means. Data generated by the sensor(s) are relayed via electrical conductor or wireless device to the Kite operational control center.
The Kite operational control center gathers data provided by sensors and human machine interface (HMI) devices, retains, and evaluates the data, then processes it with programs and/or algorithms to generate display information on an HMI(s) and transmit commands to devices that are integral to the Kite(s), Cable, or other devices on the Vessel.
FIG. 1 depicts a block diagram of a Kite propulsion control system. The central controller receives a course, trajectory, vessel loading scheme and/or destination from a user or external tracking program. The Controller receives information from the Vessel related to Vessel systems (e.g., thrust, rudder position, list sensor, orientation to the Earth's magnetic field, accelerometers). The Controller also receives information from the Kite system (e.g., carriage location, Kite cable length(s), cable tension, carriage motor torque, kite cable direction, carriage motor position). In some embodiments, the Kite also receives information from external sources (e.g., radio, satellite data, GPS, weather, wind speeds).
The Controller utilizes information received to determine a Kite's location relative to the Vessel. These data are used to locate the Kite force vector with respect to the Vessel coordinate frame. In some embodiments, the controller utilizes the Kite(s) and/or sensors along the Kite cables(s) to understand wind conditions and determine a preferred Kite elevation and orientation.
The Controller manipulates the position of the Carriage and affixed Kite relative to the Vessel's CT to steer the Vessel. The Controller can change the configuration of the Kite to manipulate the elevation of the Kite to utilize favorable winds. The Controller can also change the configuration of the Kite to modulate the Kites tensile force generated by Kite-Wind interaction. In some embodiments, the Controller modulates one or more of the Vessel propulsion system(s) and rudder(s) to optimize energy expenditure and smooth Vessel motion.
The Carriage can be moved to a designated position on the track and maintained in that position manually or with the aid of mechanical devices. In the first embodiment the Carriage position can manually be adjusted and maintained in a specific position using Cables or ropes that are pulled through a series of pulleys or blocks (e.g., with pinch block devices) as shown in FIG. 2A. FIG. 2A is an example of a manually operated Track Assembly.
In a second embodiment the Carriage can be moved and maintained by a mechanical device. The first application of the second embodiment includes but is not limited to hydraulic cylinder(s), pneumatic cylinder(s) and electromagnetic actuators.
The second application of the second embodiment is an electrical, hydraulic, or pneumatic motor or other device affixed to one or more Carriage and the Vessel. FIG. 2B depicts an embodiment where the carriage translates on a Track. The Track is rigidly connected to the Vessel. At one end of the Track is a motor with pulley. On the other end of the Track is an idler pulley. A cable is wrapped around both pulleys and connected to the carriage. As the motor rotates, it moves the cable right and left thereby moving the carriage.
In FIG. 2C, a hydraulic actuator is utilized to translate the carriage right and left on a track. In some embodiments, the hydraulic actuator extends with hydraulics and returns with spring motion. In other embodiments, the actuator is hydraulically actuated in both directions.
FIG. 2D depicts a carriage with motor and chain. A chain, or other device is fastened to the Vessel on both ends, parallel to the track. As the motor turns the chain wheel, the carriage translates left and right on the track. A power cord for the motor extends below the motor and flexes to accommodate the carriage travel. In another example, the motor or other device is equipped with a circular gear that engages with a linear gear or slotted material attached to the track, analogous to a rack and pinion. Numerous other solutions exist for translating a Carriage on a Track under power.
Relative motion between Carriage and Track can be accomplished by any number of means, including but not limited to sliding and/or rolling on bearings or wheels.

Influence of Kite Point of Connection on Vessel Direction of Travel

The marine industry has explored use of Kites on large marine and smaller Vessels to reduce fuel consumption with Wind energy. State of the art Kites are affixed via a Cable to a specific location on the Vessel, generally at or near the bow of the Vessel. The point of connection for the Cable that links the Kite to the Vessel is generally a rigid pole or similar device.
The Kite connection at or near the bow will only provide maximum energy in the direction of desired travel when the direction of desired travel is coincident with wind direction. Attachment of an external force, for example a Kite, to the bow of a ship delivers a portion of the Kite's tensile force to enhance the ship's direction of travel and part of the Kite's tensile force is used to pull the bow of the ship toward the direction of the Kite. Hence, when a Vessel elects to travel any course that differs from the direction of pull from the Kite, the ship will require a force induced by a rudder, or similar device to offset the Vessels turning moment induced by the Kit's point of connection to the Vessel's bow area. Rudder positions other than neutral introduce drag to the vessel, resulting in lost velocity and/or greater fuel expenditure.
Stated another way, when a Kite is not pulling in the direction of the Vessel's travel, the Vessel experiences a longitudinal and a lateral component to the Kite pulling force. When a Kite is attached at or near the bow of a vessel, the lateral component of the Kite force applies a moment to the Vessel that will turn the Vessel towards the Kite, owing to the fact that the Kite attachment point is in front of the center of turning. For the Vessel to maintain a path that is not aligned with the wind direction, rudders or tillers need to create a counter moment about the center of turning to counteract the Kite-induced moment and keep the vessel on its desired course.
FIG. 3 depicts the effects of Kite attachment to the bow of a Vessel. The coordinate frame of the Vessel consists of a Y axis in the longitudinal direction and an X axis in the transverse direction. The Kite is pulling at an angle Θ with respect to the Y axis. The Kite force vector can be broken into longitudinal and transverse components as Fk cos(Θ) and Fk sin(Θ), respectively. The transverse force vector is pointed to the right, applying a clockwise (CW) moment about the Center of Turning, making the Vessel steer towards the Kite.
The magnitude of the turning moment can be calculated as F_k*R, where F_kis the Kite force in the XY plane and R is the length of a vector from the center of turning to the Kite line of action that is orthogonal with the Kite line of action. Another way to calculate the turning moment is to calculate the mathematical product of the transverse force, F_T, applied to the ship at the bow (Fk sin(Θ)) and the distance from the center of turning to the Kite attachment point (L/2). In other words. Turning moment=Fk sin(Θ)*L/2.
The Z (upwards) component of the Kite force can also affect the Vessel.
The transverse, moment-generating component of the Kite force can be very large, depending on the angle, Θ. Table 1 presents the lateral force applied to a Vessel by a Kite at varying angle, Θ, The larger the angle, the larger the lateral force applied to the how of a Vessel. This results in larger turning moment and the need for greater rudder or tiller input to counter act the Kite-induced turning moment.

TABLE 1

Lateral force generated by a 1000 lb Kite force vector

	Theta, θ	Lateral Force
	(degrees)	(lbs)

	30	500
	45	707
	60	866

Hence, it can be surmised that how attachment of a Kite to a Vessel is most effective when the wind blows the Kite in the desired direction of travel. As the Kite pulling force becomes more off-axis, its benefit decreases significantly.
FIG. 4 depicts a scenario with a longitudinal-mounted track centered over the Center of turning. The point of contact between the Kite and the Vessel (i.e. the Carriage) is at the Center of Turning. In this scenario, the Kite force does not directly impart a turning moment on the Vessel.
When all external forces on the Vessel such as Vessel healing are accounted for, a Kite attachment point can be achieved that enables a Vessel to travel on a course that is not pointed at the Kite without rudder input. This is an important feature of the novel process because it allows a Vessel to optimally use wind energy without the penalty of drag from a rudder or tiller.
In the real world, there will be changes from external forces that influence the Vessel's Center of Turning location. In one embodiment, these changes in force can be compensated for in real time by making a commensurate adjustment in the location of the Kite connection point (i.e. Carriage) away from the Vessels idealized Center of Turning by a distance necessary to offset the external forces as shown in FIG. 4. In another embodiment, the position of the Coupling can be moved away from the theoretical Center of Turning by making adjustments to the Cables that affix the Kite connection to the Vessel.
FIGS. 5A and 5B depict the effects of Carriage motion to the system depicted in FIG. 4. When the desired direction of Vessel travel is not aligned with the direction of the Wind, and the Wind direction relative to the Vessel's direction is forward of the center (beam) of the Vessel (i.e. on the forward horizon, Θ≤85°), it is possible to change the Vessel's course without use of rudders/tillers by adjusting the Kites point of connection with the Vessel. The direction and magnitude of the moment applied by the Kite to the Vessel depends on the location of the Kite force vector with respect to the center of turning. In the example depicted in FIG. 5A, a counterclockwise (CCW) moment occurs when the Kite is attached to a location between the CT and the stem of the Vessel. FIG. 5B depicts how a CW moment occurs when the Kite is attached to a location between the CT and the bow of the Vessel.
As shown on FIG. 5, moving the point of connection toward the back end of the vessel (aft end) applies a CCW moment and will cause the front end of the vessel (bow) to move away from the direction of the Wind, and moving the point of connection forward will apply a CW moment causing the bow to move in the direction of the Wind.
This fore-aft movement of the Carriage can also adjust for variations in Vessel trajectory and water drag caused by vessel heeling.
Applying this concept to a catamaran, the hull that is last to experience the wind (leeward hull) will be exposed to more water friction than the hull that is first to be exposed to the Wind (windward hull) and the differences in hull drag will tend to cause the vessel to turn in the direction of the leeward hull. An adjustment of the Kite(s) point(s) of connection on the Vessel toward the aft will compensate for the drag on the leeward hull without the use of additional drag induced by rudders or equivalent steering apparatus.
FIGS. 6A & 6B illustrate an embodiment of the Turning effect caused by transverse movement of the Kite attachment point that intersects the Center of Turning. FIG. 6A shows how the Vessel will turn counterclockwise when an extension of the Kite force F_kline (shown in dashed line) intersects the “Y” axis (marked with a circle) to the stern of the Vessels CT and FIG. 6B shows how the vessel will turn clockwise when the Kite force F_kline intersects the “Y” axis (shown with a circle) toward the bow of the Vessels CT.
The ability to maintain or change a vessel's course to port or starboard is a function of the direction and magnitude of the turning moment created by the Kite force about the Center of Turning. As the Carriage position moves away from the Center of Turning, the amount of leverage to create a turning moment increases. When the line of force from the Kite (or an extension thereof) crosses the center of turning, no turning moment is applied to the vessel directly by the Kite. This novel placement of Kite connection to the Vessel provides an ability to maintain a course and change course without the added friction caused by using a rudder or tiller.
FIGS. 7A and 7B depict a Kite pulling towards the starboard side of the Vessel with a transversely mounted track positioned behind (toward Vessel's stern) the Center of Turning by a large percentage of the Vessel length. In this example, the Kite force applies a CCW moment that causes the Vessel to turn to left (port) irrespective of the Carriage position along the track. This is because R is always on the same side of the center of turning and the external force Fk intersects the Vessels “Y” axis to the stern of the CT position. Hence, the Track must be mounted close enough to the center of turning along the length of the Vessel (or sufficiently wide) that the Carriage can locate the Kite force to either side of the center of turning to impart both CW and CCW moments.
FIG. 7A depicts a Carriage on the right side of the track. FIG. 7B depicts the Carriage on the left side of the track. The Kite force is the same in both images, however the distance R from the line of action of the Kite force to the center of turning varies. The larger R value in FIG. 7A creates a larger CCW turning moment for the Vessel in the left (port) direction than the Carriage position shown in FIG. 7B for the same kite force.
FIGS. 8A and 8B depict the effect a change in angle, Θ has on the applied turning moment. In FIG. 8A, the Kite force is applied in the generally starboard direction. The carriage is located at the port end of the Track and a CCW moment is applied to the vessel because the external force Fk crosses the Vessels “Y” axis to the aft of the CT. In FIG. 8B, the Kite force is applied in a generally forward direction. The Kite line has crossed the center of turning toward the bow and generates a CW moment about the center of turning to make the Vessel turn towards starboard. FIGS. 8A and 8B provide additional examples of how a Vessel can turn away from or into the wind without the aid of rudder/tiller.
FIGS. 9A and 9B are a continuation of the story told in FIGS. 8A and 8B. This figure clearly shows how changes in placement of the track on the Vessel create different turning forces for Vessels with the same Θ value and Carriage position on the track. The F_kKite force vector shown in FIG. 9B is on the portion of the Y axis that is forward of the CT, therefore the turning moment will direct the Vessel to the right (into the Wind). Conversely the Vessel depicted in FIG. 8A with the same angle has the F_kKite force vector that crosses the Y axis to the aft of the CT position so the turning moment will force the vessel to turn to the left.
FIGS. 10A and 10B depicts the mechanics of a transverse-mounted track located in front of the center of turning. FIG. 10A depicts the carriage at the port end of the track so that the Kite force vector crosses the longitudinal axis (Y axis) of the Vessel in front of the Center of Turning, resulting in a clockwise moment. FIG. 9B depicts the carriage at the starboard end of the track so that the Kite force crosses the longitudinal axis behind the Center of Turning resulting in a counterclockwise moment. In some embodiments, the track is not aligned with the center of turning. FIGS. 11A and 11B depict an embodiment where the track is located along the deck railing of a Vessel. As can be seen in the figure, fore-aft adjustment of the Carriage provides CW and CCW moments about the Center of Turning, respectively. This location provides a low Kite attachment point for reduced tilting moment. Side-mounted track also minimizes interference between the Kite system and equipment and freight located on the Vessel deck. A side mounted Track can be as long as the Vessel in some applications.
The sides of a Vessel hull are typically very strong and can accommodate the loads applied from a track. In some embodiments, the hull is reinforced to accommodate, the track, Carriage and Kite loads. In some embodiments, the elevation of the side-mounted track is at the deck railing. In other embodiments. the elevation of the track is below the deck railing, along the side of the vessel. Lower attachment points result in less tilting moment applied to the vessel from the Kite. In general, the track is not located at or near the water line due to the potential for salt-water contamination of Kite system components.
The side-mounted track in FIG. 10 functions well for a Kite on the starboard side. Typically, an equivalent track is utilized on the port side for port side Kite loads. Various embodiments exist for transferring the Kite connection point from one side of the Vessel to the other. FIG. 12 depicts a Vessel with Tracks along each side. The Kite cable is managed with a spool at the Bow. The Kite cable is guided through pulleys at the bow and on the Carriage to locate the Kite connection point to the Vessel. Coordinated motion is required between the spool and Carriage to maintain a particular Kite altitude. Multiple solutions exist for translating the Carriage along the track, including but not limited to additional cables, or a carriage-mounted motor. In some embodiments, the Carriage is powered by electrical power rails in the Track. Transfer from port to starboard (or vice versa) involves transferring the Kite cable from the Carriage on side of the Vessel to a Carriage on the other side of the Vessel.
FIG. 13 depicts an embodiment with continuous track from the port side to the starboard side of the Vessel. This embodiment enables continuous operation of the Kite system and automated compensation when the Kite force crosses the centerline of the Vessel. In some embodiments, the Kite cable spool is located on the Carriage. In other embodiments, the Kite cable is managed with pulleys from a Vessel-mounted spool. In some embodiments, the Kite is depowered as the Carriage nears the bow or crosses the center line to minimize disruption to the Vessel and rudder input.
FIG. 14 depicts a Kite-powered. Vessel executing a jibe turn, (when the ship stern crosses through the wind). Starting with the left image, the Vessel is traveling in direction Y with Fk applying a moment to steer the ship towards Port. In the second image, the Carriage is moved forward on Starboard side to turn the ship towards the Kite with a CW moment. In the third image, the Vessel rotates across the Kite direction. In some embodiments, the Carriage is passively dragged around the curved track at the front of the Vessel. In other embodiments, the Carriage is actively driven around the curved track. In the fourth image, the Carriage travels down port side to steer the ship.
FIG. 15 depicts an embodiment that utilizes a continuous cable guided by pulleys that circumscribes all or part of the Vessel hull. The carriage is connected to a location on the cable and travels with the cable as it is moved. The track is continuous around the bow of the Vessel. In the embodiment depicted, the cable is moved by a pulley mounted in the bow of the Vessel, however the drive pulley could be located at any point along the cable.
The number of forces and moments acting on a Vessel hull at any one time is complex. FIG. 16 presents an example of the moments applied to a Vessel from water pushing on the hull (tilt steering moment) and from the Kite steering moment. Manipulation of the Kite attachment point provides the ability to direct the vessel in multiple directions independent of the tilt moment.

Sensors and Controls

It is well documented that at any given location on the planet, the wind direction, temperature, and velocity vary with change in elevation.
The use of Kites described in this document provide features and benefits not available to sailing Vessels that support sails from fixed masts. Conventional sails attached to masts do not have the ability to be influenced by Wind force and direction at elevations significantly above sea level, for example hundreds or thousands of feet above sea level, but Kites do.
Two types of Kites are applicable to Vessel propulsion: Stable and unstable. Unstable Kites conventionally used on Vessels are limited to altitudes of a few hundred feet above sea level. Furthermore, unstable Kites result in a continuously changing Kite force vector. For large, heavy vessels where the Kite force makes up a small fraction of the vessel propulsion, this variance in Kite force vector is trivial. However, for smaller craft relying significantly or solely on Kite propulsion, this variation in Kite force vector results in inefficiency and complexity. In embodiments of a Kite/carriage system where unstable Kites are used, carriage location can be adjusted in real time to compensate for variations in Kite force vector direction to keep a vessel course.
A further limitation to mast-mounted sails and conventional Kites is that they do not have access to the faster Wind speeds and multiple Wind directions available to higher flying Kites.
The technology included in this process description enables Kite(s) and Cable(s) to accommodate instruments and control technology that sense weather and air conditions at different elevations and then change the Kite(s) elevation as required to provide the Vessel with additional Kite powered directions and rates of travel. FIGS. 17A, 17B, 17C, and 17D describe some of the possible instrumentation that can be used to gather weather, air, and wind data.
A Kite(s) lifts the Cable or other device that connects it to a Vessel. The mass of the Cable provides a practical elevation limit. Polymeric Cables made from materials like Dyneema or Spectra provide sufficient strength with low weight. These features allow more available Cable length to reach higher elevations with the propensity to have different Wind properties and therefore more options to access Kite force that can be utilized for Vessel propulsion.
In one instrument use embodiment, the elevation of the Kite is adjusted up and down to characterize the gradient of the wind speed and direction, then the Kite elevation is adjusted in the direction that provides greater Kite force or a component thereof in the direction of Vessel travel. In another embodiment, Kite elevations are swept (i.e. evaluated) periodically to determine the optimum Kite elevation.
In another embodiment, sensors are mounted along the length of the main Kite Cable to measure one or more of Wind speed, Wind direction, temperature, and pressure. In another embodiment, sensors are placed on a Cable that extends to a pilot chute for data collection at elevations above the Kite. In another embodiment, a weather sensing device with wireless communication travels up and down a Kite Cable, collecting data as it travels. The information from the weather sensing device is transmitted to the main Kite control system either continuously or in packets. Information from these sensor systems is used to determine the optimal elevation of the Kite. The optimal elevation can vary real time, requiring continuous adjustment. In one embodiment, an automated system collects Kite sensor data and adjusts Kite elevation and/or Kite attachment location in real time.
FIG. 17A depicts a Vessel with a transversely mounted Track. The Kite Cable extends from the carriage up to a Lift Kite and a Pilot Kite. Discrete sensors are located along the length of the Kite Cable for data collection.
FIG. 17B depicts an example of a Kite Line-mounted sensor capable of measuring wind direction, pressure, temperature, and wind speed. In another embodiment (not shown), Kite line sensors are removably attached and include a mechanism to scale (i.e. traverse) the line. When information is to be collected, Kite users attach a Kite sensor to the Kite cable and the sensor climbs the cable is extended, collecting data as it ascends and descends.
FIG. 17C depicts an alternative embodiment of a Kite Cable-mounted sensor assembly consisting of a collar rigidly mounted to the Cable with pressure sensors around the periphery. Embodiments with 3 or more pressure sensors mounted around the periphery of the ring can be sufficient to determine a wind vector direction by calculating the direction of the highest pressure. When absolute pressure sensors are utilized, the pressure measurement can be indicative of atmospheric pressure and/or altitude. In some embodiments the cable-mounted sensor is powered by electrical conductors in the Kite cable. In other embodiments, the cable-mounted sensor assembly is powered by an internal battery. The embodiment shown includes a data acquisition processor (DAQ), battery (BAT) and wireless antenna (ANT). Data measurements are communicated to the central control computer via either wired or wireless means. In general, measurements are digitized before transmission for more robust data transfer. In some embodiments, the cable-mounted sensor array includes an electronic compass or other means to orient the wind vector with respect to inertial space.
FIG. 17D depicts another embodiment of a Kite Cable-mounted sensor that includes a weathervane, mini generator, and propeller. Wind directs the weathervane to be parallel to the wind and the plane of the propeller to be orthogonal to the wind direction. The wind turns the propeller at a rate proportional to wind speed, turning a generator that generates an electrical signal proportional to wind speed. In some embodiments, the wind speed is determined by the rotational rate of a propeller, as measured by an optical device, or equivalent means. In other embodiments, the amount of power generated by the generator is utilized as a proxy for wind speed. In some embodiments, there are two propellers: one for wind speed measurement and one for power generation.

Deployment and Retrieval of a Kite

The methodology described in this document is Vessel specific but there are some generalities. The Kite(s) are only used in open waters, away from obstacles, for example bridges and power lines that are common in harbors. Deployment requires orienting the Vessel in a way that the Kite launching area is downwind. A pilot Kite as shown in FIG. 17A is released first. Once it is stable in flight, it is used to pull the main Kite into the air. Kite retrieval is performed by reeling in the Kite's Cable. In some embodiments, a Kite is depowered by reducing the surface area the Kite exposes to the Wind prior to or during retrieval. FIG. 18 depicts one method of changing a Kites pull on the Cable. This is used for depowering at Kite retrieval and adjustment of Kite force as required for desired Vessel speed.
There are many ways to store Cable used to connect the. Kite to the Carriage. In the first embodiment, it can be wound around a drum with motorized release and retrieval and with layering mechanism similar to that used on a fishing reel. The drum assembly also includes an ability to release and retract Cable at varying rates. The drum assembly can be located in any area that is convenient. For example, it can be located near the Track Assembly or at any location, on the Vessel, and then Cable is routed with pullies or other devices to the Carriage affixed to the Track Assembly. In the second embodiment, the Cable can be stored in a toroidal shaped container with rectangular or other shape. The shape stores and removes cable from an opening on the inner radius or other location as shown in FIG. 19. The toroidal shape is ideally motorized to deploy or retrieve the Cable at variable rates and can be oriented horizontally, vertically, or at any other angle.

Kite Design

FIG. 20 illustrates an embodiment of Examples of Kite designs. Stable Kites provide consistent pulling force for a Vessel with minimal control effort required. Several designs provide stable Kite pulling force including, but not limited to, barn door design (19A), Rokkaku (19B), Dopero (19C) and parafoil designs (19D). All of these designs are examples of Kite technology that by their design are inherently stable in flight and pulled from a single Cable. Both of these attributes are desirable in a Kite design.
In some embodiments, a maneuverable (less stable) Kite can be controlled at a stable point when sufficient cables are utilized. The use of a maneuverable Kite with sufficient control cables enables a User or automated system to place and hold the Kite in an orientation with respect to the wind that generates maximum cable tension for maximum Vessel pulling three. An example of a maneuverable Kite is a parafoil design with four control cables, as shown in FIG. 21. The foil Kite is controlled by left and right control cables and left and right brake cables.
In some embodiments, a Kite with inflatable leading edge is utilized as shown in FIG. 18. This design facilitates recovery after the Kite touches down on water. In other embodiments, open cell foils are utilized.

Kite Power Adjustment

Wind acting on the Kite to form drag forces and lift forces are the sources of Kite force applied to a Vessel. Features that add to Kite drag and lift include: Kite area; Presence/absence/size of a Kite tail. A tail provides drag (pulling force) and keeps Kite oriented against the wind; and Presence/absence/size of a pilot chute.
In some embodiments, the amount of drag of a Kite is adjustable. This can be beneficial in the event of extreme winds or to facilitate retrieval of a Kite. In one embodiment, Kite force is automated adjustment by opening/closing windows in the surface of the Kite as shown in FIG. 22. In another embodiment, the length of the tail of a Kite is adjustable in order to vary Kite force. In another embodiment, Kite throe adjustments are made electronically by servomotors on the Kite as shown in FIG. 23. Power to the motors can be from electrical cables within the main Kite Cable or from batteries on board the Kite or solar cells mounted on the Kite. In one embodiment, the Kite is adjusted via remote control through a wireless (e.g., Bluetooth, or RF) connection.
FIG. 22 depicts an embodiment where the openings at the leading edge of a Kite can be collapsed by cinching a cable or rope that encircles one or more of the air channel openings. As the cable/rope is tightened, the frontal area of the Kite decreases, causing drag.
FIG. 23 depicts another embodiment of a Kite that achieves adjustable lift via adjustable flaps on its surface that allow varying amount of air to escape from the Kite. In one embodiment, flaps are adjusted from the Vessel by means of Cables. In another embodiment, motors on the Kite adjust the opening size via sliding panels. In one embodiment, the opening is covered by a mechanism resembling a motor-driven roll-up window shade with return springs that shut the shade in the absence of force from the motor.
FIG. 24 depicts a Carriage design with four independent motor-driven spools for controlling Kite control and brake cables. In some embodiments, cable length is adjusted by each spool independently as the Carriage moves to maintain Kite position and stability. The Kite is released to higher elevations by unwinding all spools simultaneously. The Kite is depowered by turning the brake spools to reel in cable. In some embodiments, the spools of cable and motors are located on the Carriage.
FIG. 25 depicts a Carriage that manages. Kite cable with pulleys. The length of each Kite cable is controlled by spools that are attached to the Vessel. In some embodiments, the spools are manually turned. In other embodiments, the spools are turned by motor. In some embodiments, motors are controlled by an automated Kite control system. As the carriage moves along the track, the motor-driven spools collect and release Kite line to maintain a constant altitude and attitude of the Kite when so desired. In some embodiments, the bracket that connects the pulleys to the carriage are binged about an axis parallel to the track. This hinge permits the pulleys on the carriage to adjust their angle with respect to horizontal as the Kite lifts from sea level into the air. When the Kite is level with the vessel, the pulleys are at or near horizontal. As the Kite ascends into the sky, the pulleys passively rotate on their respective hinges so that the plane of the pulleys is aligned with the Kite cable and Kite. In some embodiments, the incline of the plane of the Kite pulleys with respect to horizontal is instrumented with a sensor (e.g., inclinometer, potentiometer, encoder) to provide information on the direction of the Kite force vector. In some embodiments, the force applied from the Kite to the carriage, and/or the carriage to the track, and or the track to the Vessel is measured with one or more sensors (e.g., strain gages, load cells, etc.). In some embodiments, the Kite control system uses Kite cable motor torque and/or current as a proxy for Kite cable tension.

Claims

What is claimed is:

1. A method of improving the performance of a vessel, comprising:

a) attaching one or more cables from the vessel to a kite or similar device;

b) deploying the kite or similar device into wind;

c) transferring energy from the wind into an external force vector applied through the one or more cables; and

d) selectively locating an overall force vector at a variable location with respect to the vessel, wherein the force vector imparts either a forward propulsive force or a forward propulsive force and a variable turning moment.

2. The method of claim 1, wherein when the external force vector crosses the vessel's center of turning, there is only a forward propulsive force and no turning moment.

3. The method of claim 1, wherein when the external force vector or an extension of the external force vector crosses the vessel's longitudinal axis in front of the vessel's center of turning, the turning moment is in a clockwise direction.

4. The method of claim 1, wherein when the external force vector or an extension of the external force vector crosses the vessel's longitudinal axis behind the vessel's center of turning, the turning moment is in a counterclockwise direction.

5. The method of claim 3, wherein the magnitude of turning moment is varied by adjusting the radial distance from the center of turning to the external force vector.

6. The method of claim 4, wherein the magnitude of turning moment is varied by adjusting the radial distance from the center of turning to the external force vector.

7. The method of claim 1, wherein the external force vector is variably located with respect to the vessel by connecting cables from the kite or similar device to a carriage that is constrained by a track.

8. The method of claim 7, wherein the track is a linear and longitudinally mounted track.

9. The method of claim 7. wherein the track is a linear and transversely mounted track.

10. The method of claim 7, wherein the track is located on or around a perimeter of the vessel.

11. The method of claim 1, wherein the external force vector is variably located with respect to the vessel by connecting cables from the kite or similar device to a connection point and varying the length of two or more vessel-mounted cables of variable length that define the location of the connection point to the external force vector.

12. The method of claim 1, wherein vessel efficiency is improved by eliminating drag associated with use of a rudder or tiller.

13. The method of claim 1, Wherein location of the external force on the vessel is automatically and dynamically varied to maintain a specified vessel course.