MECHANISM FOR DIRECT ACTUATION OF THE TAIL OF A SELF-TRIMMING WINGSAIL

Abstract

A self-trimming wingsail system, comprising a wingsail body mounted on a mast and configured to rotate freely around the mast, an adjustable tail connected to the wingsail body, and a tail control mechanism configured to adjust an angle of the adjustable tail. The tail control mechanism comprising a motor, and a slidable collar connected to the motor via a collar cable and connected to the adjustable tail via a tail cable. Movement of the slidable collar transmits a linear force via the tail cable to the adjustable tail to adjust the angle of the adjustable tail.

Claims

1. A self-trimming wingsail system, comprising: a wingsail body mounted on a mast and configured to rotate freely around the mast; an adjustable tail connected to the wingsail body; and a tail control mechanism configured to adjust an angle of the adjustable tail, the tail control mechanism comprising: a motor, and a slidable collar connected to the motor via a collar cable, and connected to the adjustable tail via a tail cable, wherein movement of the slidable collar transmits a linear force via the tail cable to the adjustable tail to adjust the angle of the adjustable tail.

2. The self-trimming wingsail system of claim 1, wherein the adjustable tail is mechanically attached to a frame of the wingsail body via a rigid frame structure.

3. The self-trimming wingsail system of claim 1, wherein the slidable collar, the collar cable and the tail cable are internal to the wingsail body.

4. The self-trimming wingsail system of claim 1, wherein the tail control mechanism further comprises a series of pulleys configured to facilitate a change in direction of the force applied to the slidable collar and the adjustable tail.

5. The self-trimming wingsail system of claim 1, wherein the tail control mechanism further comprises a series of linkages configured to translate a linear motion of the collar into an angular adjustment of the tail.

6. The self-trimming wingsail system of claim 1, wherein the tail control mechanism further comprises a collar bearing positioned around the mast, the collar bearing facilitating free rotation of the slidable collar around the mast.

7. The self-trimming wingsail system of claim 1, wherein the tail cable includes a first tail cable attached to a first side of the slidable collar and a second cable attached to a second side of the slidable collar.

8. The self-trimming wingsail system of claim 1, further comprising a controller configured to control the motor based on sensor data to adjust the angle of the adjustable tail.

9. The self-trimming wingsail system of claim 8, wherein the sensor data includes at least one of data related to the angle of attack of the wingsail, wind direction and speed of the wingsail system.

10. The self-trimming wingsail system of claim 8, wherein the controller is configured to monitor the sensor data and make adjustments to the tail angle based on the sensor data to maintain a desired angle of attack of the wingsail.

11. A method of adjusting an angle of attack of a wingsail, comprising: controlling, by a controller, a motor of a tail control mechanism to move a slidable collar along a mast, the slidable collar connected to the motor via a collar cable, and connected to an adjustable tail via a tail cable; applying, by the slidable collar via the collar cable, a linear force via the tail cable to the adjustable tail to adjust the angle of the adjustable tail; and applying by the adjustable tail, an adjustment force to a freely rotating wingsail body mounted on the mast.

12. The method of claim 11, further comprising: applying the adjustment force to the wingsail body via a rigid frame structure connecting the wingsail body to the adjustable tail.

13. The method of claim 11, further comprising: controlling, by the controller, the slidable collar and the adjustable tail via a set of pulleys and linkages.

14. The method of claim 11, further comprising: controlling, by the controller, the motor based on sensor data to adjust the angle of the adjustable tail.

15. The method of claim 14, wherein the sensor data includes at least one of data related to the angle of attack of the wingsail, wind direction and speed of the wingsail.

16. The method of claim 14, further comprising: making adjustments, by the controller, to the tail angle based on the sensor data to maintain the angle of attack of the wingsail.

17. The method of claim 14, further comprising: controlling, by the controller, the motor based on a combination of the sensor data and predetermined sailing parameters to adjust the angle of the adjustable tail.

18. The method of claim 17, wherein the predetermined sailing parameters include navigation parameters.

19. The method of claim 11, further comprising: receiving, by a wireless transceiver, instructions for instructing the controller in adjusting the angle of attack of the wingsail.

20. The method of claim 19, wherein the instructions provide autonomous control to the wingsail.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] So that the way the above-recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be made by reference to example embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only example embodiments of this disclosure and are therefore not to be considered limiting of its scope, for the disclosure may admit to other equally effective example embodiments.

[0026] FIG. 1 illustrates an exemplary sailboat with a self-trimming wingsail system, according to aspects of the present disclosure.

[0027] FIG. 2 presents a top view of the self-trimming wingsail system in various positions relative to the wind direction, according to aspects of the present disclosure.

[0028] FIG. 3A depicts a side view of a self-trimming wingsail system, illustrating the components and their interaction for controlling the self-trimming wingsail, according to aspects of the present disclosure.

[0029] FIG. 3B shows a perspective view of a self-trimming wingsail system with a controllable tail, illustrating the internal mechanical components and their interactions, according to aspects of the present disclosure.

[0030] FIG. 4A presents a process for actuating a self-trimming wingsail using a motor control mechanism, according to aspects of the present disclosure.

[0031] FIG. 4B depicts a process for adjusting the angle of attack of a self-trimming wingsail on an autonomous sailboat, according to aspects of the present disclosure.

DETAILED DESCRIPTION

[0032] Various example embodiments of the present disclosure will now be described in detail with reference to the drawings. It should be noted that the relative arrangement of the components and steps, the numerical expressions, and the numerical values set forth in these example embodiments do not limit the scope of the present disclosure unless it is specifically stated otherwise. The following description of at least one example embodiment is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or its uses. Techniques, methods, and apparatus as known by one of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate. In the examples illustrated and discussed herein, any specific values should be interpreted to be illustrative and non-limiting. Thus, other example embodiments may have different values. Notice that similar reference numerals and letters refer to similar items in the following figures, and thus once an item is defined in one figure, it is possible that it need not be further discussed for the following figures. Below, the example embodiments will be described with reference to the accompanying figures.

[0033] The present disclosure relates to a wingsail system for a sailboat, particularly to a mechanism for controlling the tail (herein referred to as the adjustable tail) of a free rotating wingsail resulting in a controllable wingsail herein referred to as a self-trimming wingsail. In some aspects, the self-trimming wingsail system may include a wingsail body mounted on a fixed mast of the sailboat and configured to rotate freely around the mast, an adjustable tail connected to the wingsail body, and a tail control mechanism configured to adjust an angle of the adjustable tail. The tail control mechanism may include a motor and a slidable collar connected to the motor via a collar cable and connected to the adjustable tail via a tail cable. Movement of the slidable collar may transmit a linear force via the tail cable, belt, chain or the like to the adjustable tail to adjust the angle of the adjustable tail. In operation, the wind force acting on the adjusted tail exerts a force on the wingsail via a rigid frame, causing the wingsail to adjust its angle of attack to optimize the sailboat's performance.

[0034] The disclosed self-trimming wingsail system may offer several advantages including aerodynamic efficiency, precise control, reduced heeling, better maneuverability in high winds, and enhanced lifetime. These advantages may make this self-trimming wingsail system particularly suitable for autonomous wind-powered navigation. Furthermore, the tail control mechanism of the self-trimming wingsail system may allow for precise control of the adjustable tail angle, which can be a challenge due to the sail's free rotation around the mast. This control mechanism may solve the technical problem of providing a reliable and efficient method of controlling the tail angle of a wingsail.

[0035] A notable advantage of the disclosed self-trimming wingsail system is that the innovative design of the wingsail system ensures that no power or signal lines are necessitated within the main wing structure of the wingsail, thereby simplifying the design and reducing potential points of failure. The actuation of the self-trimming adjustable tail is achieved through a transmission mechanism that adeptly manages the constraint of free rotation, allowing for the self-trimming adjustable tail to be precisely controlled from the hull of the sailboat. This design choice eliminates the complexity and maintenance challenges associated with penetrating the mast to transmit control signals or power, as the effort is transmitted along the mast via accessible cables.

[0036] The transmission mechanism employed in the self-trimming wingsail system comprises marine-grade ropes and pulleys (or similar devices such as cables, belts and chains), selected for their durability and reliability in the demanding marine environment. These components are specifically engineered to withstand the corrosive and dynamic conditions encountered at sea, ensuring the long-term dependability of the system. Moreover, the control mechanism operates on a linear principle, meaning that the relationship between the motor's angle and the adjustable tail angle is direct and fixed. This linear control simplifies the calibration and operation of the system, as it involves rotational movements in the transmission. This straightforward and robust design translates to a self-trimming wingsail system that is not just efficient and reliable, but also user-friendly and easy to maintain.

[0037] In addition, a benefit of the disclosed self-trimming wingsail system is its energy efficiency, particularly in the operation of the tail control mechanism. The tail control mechanism, which includes a motor and a slidable collar connected via a collar cable and a tail cable, is designed to adjust the angle of the adjustable tail of the wingsail. This adjustment is achieved by transmitting a linear force from the slidable collar to the adjustable tail via the tail cable. The force applied by the motor to move the slidable collar is relatively small, which results in low power consumption.

[0038] Furthermore, the design of the self-trimming wingsail system allows the wind force acting on the adjusted tail to exert a force on the wingsail via a rigid frame, causing the wingsail to adjust its angle of attack. This process leverages the natural wind energy to adjust the wingsail, thereby reducing the reliance on the motor and further contributing to the energy efficiency of the system.

[0039] Moreover, the motor of the tail control mechanism can be controlled by a controller with more precision if sensor data (e.g., wingsail angle data, adjustable tail angle data, etc.) is available, allowing for precise and efficient adjustments of the tail angle. This intelligent control further minimizes unnecessary power consumption by making precise adjustments as per the requirements, rather than continuous operation.

[0040] In some aspects, the present disclosure may include controlling a motor of a tail control mechanism to move a slidable collar along a mast of the sailboat, applying a linear force via a tail cable to an adjustable tail to adjust the angle of the adjustable tail, and applying an adjustment force to a self-trimming wingsail body mounted on the mast of the sailboat. This method may provide a technical solution to the problem of controlling the angle of attack of a self-trimming wingsail, thereby improving the performance and efficiency of the sailboat.

[0041] In some cases, the self-trimming wingsail system and method may be controlled by a controller based on sensor data to adjust the angle of the adjustable tail. The sensor data may include data related to the angle of attack of the main wing structure of the self-trimming wingsail, wind direction, and speed of the sailboat to name a few and last but not least, the motor command feedback or optionally the angle of the adjustable tail to provide feedback in the end of transmission. The measure of the adjustable tail angle may be beneficial for controlling the sailboat. However, obtaining this measurement can be a challenge as electrical wires routed to the adjustable tail may twist with the free-rotation of the self-trimming wingsail. The controller may monitor the sensors and make adjustments to the tail angle based on the sensor data to maintain a desired angle of attack of the self-trimming wingsail. This may provide a technical solution to the problem of maintaining a desired angle of attack of a self-trimming wingsail in varying wind conditions, thereby improving the performance and efficiency of the sailboat.

[0042] The self-trimming wingsail system, as disclosed in this application, will now be described in detail with reference to the accompanying figures. These figures illustrate various aspects of the self-trimming wingsail system, including its components, their arrangement, and their interaction for controlling the self-trimming wingsail. The figures also depict processes for actuating the self-trimming wingsail using a motor control mechanism and for adjusting the angle of attack of the self-trimming wingsail on an autonomous sailboat. It is to be understood that the figures are for illustrative purposes and are not drawn to scale. The relative dimensions and arrangement of the parts in the figures may be exaggerated for clarity and are not necessarily indicative of the actual relative dimensions and arrangement of the parts.

[0043] Referring to FIG. 1, a side view of a sailboat 100 is depicted, equipped with a self-trimming wingsail system. The sailboat 100 includes a boat hull 102 (monohull, multihull, etc.), to which a mast base 104 is affixed. Rising vertically from the mast base 104 is a mast 106, which supports a wingsail 108 and adjustable tail sections 112 and 114 via a tail support frame 110. In some aspects, the mast 106 may be constructed from lightweight and durable materials such as carbon fiber or aluminum, providing the structural support for the wingsail 108 and adjustable tail sections 112 and 114.

[0044] At the top of the mast 106, a wingsail rotation axis 106A is shown, suggesting the ability of the wingsail 108 to rotate freely around the mast 106 within an allowed range of motion. This free rotation of the wingsail 108 around the mast 106 allows the wingsail 108 to adjust its angle to the wind, optimizing the lift generated by the wingsail 108 and improving the performance of the sailboat 100. In some cases, the wingsail rotation may be implemented using bearings (top and bottom) or other rotational mechanism that allows for smooth and unrestricted rotation of the wingsail 108 around the mast 106.

[0045] The wingsail 108 may be connected to adjustable tail sections 112 and 114, which are rotatable around a tail rotation axis 112A. The rotation of the adjustable tail sections 112 and 114 may be controlled by a force applied by a cable (not shown in FIG. 1) running up the mast 106 and across the tail support frame 110. This cable-driven mechanism allows for precise control of the angle of the adjustable tail sections 112 and 114, which in turn influences the angle of attack of the wingsail 108. In some aspects, the cable may be controlled by a motor or other actuation mechanism which may be located at the bottom of mast 106 (e.g., in base 104) or elsewhere on the sailboat 100.

[0046] Wingsail 108 and adjustable tail sections 112 and 114 may be designed with an aerodynamic shape to increase the lift generated by the wind, improving the speed and stability of the sailboat 100. The wingsail 108 and adjustable tail sections 112 and 114 may also be adjustable to optimize their shape and angle for different wind conditions and sailing scenarios. This multi-section design allows for nuanced control of the tail's angle, thereby enabling a more precise adjustment of the wingsail's angle of attack. Alternatively, the tail may also be designed with a single section, depending on the specific requirements of the sailboat's operation. The shape, size, and positioning (e.g., distance between wingsail and tail sections, height of tail sections relative to the wingsail, etc.) of the tail section(s) may be dependent on the shape and size of the wingsail and the sailboat. This interdependence ensures that the tail and the wingsail work in harmony to optimize the lift generated by the wingsail, thereby improving the performance and efficiency of a given sailboat. The tail's design and its relationship with the wingsail effect the operation of the self-trimming wingsail system, contributing to its aerodynamic efficiency, precise control, and enhanced performance in various wind conditions.

[0047] Although FIG. 1 shows the self-trimming wingsail system implemented on a sailboat, the self-trimming wingsail system disclosed herein can be beneficial to a wide range of sailboats and motorized boats. For sailboats, including monohulls, multihulls (such as catamarans and trimarans), and even high-performance racing sailboats, the self-trimming wingsail system can provide improved aerodynamic efficiency, precise control, and enhanced performance, especially in varying wind conditions. The system's ability to automatically adjust the angle of attack of the wingsail can be particularly advantageous for autonomous sailboats, reducing the complexity of sail handling and navigation. For motorized boats, the self-trimming wingsail system can serve as an auxiliary propulsion system, providing fuel-saving benefits. When the wind conditions are favorable, the motorized boat can switch to the self-trimming wingsail system for propulsion, saving fuel and reducing emissions. Furthermore, the self-trimming wingsail system can be beneficial for hybrid boats that use both sails and engines for propulsion, offering a versatile and efficient solution for various sailing scenarios.

[0048] Turning now to FIG. 2, a top view of a self-trimming wingsail system in various positions relative to the wind direction is depicted. FIG. 2 illustrates three different positions of the wingsail 202, namely a neutral position wingsail 200A, a tacking position wingsail 200B, and an opposite tacking position wingsail 200C. In some aspects, the wingsail 202 may be configured to rotate freely around a mast 204, which may be central to the self-trimming wingsail system. This free rotation of the wingsail 202 around the mast 204 allows the wingsail 202 to adjust its angle to the wind, optimizing the lift generated by the wingsail 202 and improving the performance of the sailboat. Line 210 represents the bow to stern axis of the boat hull.

[0049] At the rear of the wingsail 202, an adjustable tail 206 may be positioned in a desired posture. The adjustable tail 206 may be configured to pivot at an adjustable tail pivot point 208, allowing for precise control of the angle of the adjustable tail 206. In the neutral position wingsail 200A, the wingsail 202 and adjustable tail 206 are inline with one another, such that the wingsail axis 212 and adjustable tail axis 214 are coaxial. However, in the tacking positions, the adjustable tail 206 pivots at the adjustable tail pivot point 208 to create a relative angle between the wingsail 202 and the adjustable tail 206, as measured from the wingsail axis 212 and the adjustable tail axis 214. This relative angle allows the wind to apply a force to the adjustable tail 206, which then translates this force to a rotational force on the wingsail 202. In other words, wind force applied to adjustable tail 206 forces the wingsail 202 to tack as desired.

[0050] In some cases, the self-trimming wingsail system may be controlled based on sensor data to adjust the angle of the adjustable tail 206. The sensor data may include at least one of data related to the angle of attack of the wingsail 202, wind direction, and speed of the wingsail (e.g., speed of the sailboat or any other vehicle to which the wingsail is mounted) to name a few options. This sensor data may be used to control the position of the adjustable tail 206, thereby adjusting the angle of attack of the wingsail 202 and improving the performance of the sailboat.

[0051] As noted above, the angle of attack on the tail directly influences the angle of attack on the wingsail. This is due to the mechanical linkage between the tail and the wingsail, facilitated by the tail control mechanism. When the tail control mechanism, driven by a motor, adjusts the tail to a more aggressive angle, it exerts a force on the wingsail via a rigid frame. This force, in turn, causes the wingsail to adjust its angle of attack correspondingly. Therefore, a more aggressive angle of attack on the tail results in a more aggressive angle of attack on the wingsail. This interplay between the tail and the wingsail allows for precise control of the wingsail's angle of attack, optimizing the lift generated by the wingsail and improving the performance of the sailboat.

[0052] It is noted that the self-trimming wingsail system is designed to orient the main wing relative to the apparent wind, a dynamic parameter that combines the true wind with the sailboat's motion-induced wind. As the relative angle between the adjustable tail and the main wing increases, so does the incidence of the main wing to the apparent wind, enhancing the sailboat's propulsion. The ability to trim the adjustable tail relative to the main wing is a beneficial characteristic of the disclosed self-trimming wingsail system. This trimming is not arbitrary but may be calibrated to the apparent wind's direction and speed, which is the wind experienced by the moving sailboat. The tail control mechanism, therefore, does not merely adjust the tail's angle in a vacuum but does so in response to the apparent wind conditions. This responsiveness to the apparent wind is what allows the wingsail to self-adjust its angle of attack, optimizing the aerodynamic lift and thus the sailboat's performance. The system's design ensures that as the angle between the tail and the main wing increases, the wingsail's angle of attack to the apparent wind also increases, providing a more efficient and responsive sailing experience.

[0053] Referring now to FIG. 3A, a side view of a wingsail assembly side view 300 is depicted, illustrating the components and their interaction for controlling the wingsail. The wingsail 108 may be connected to the wingsail mast 106, which is supported by the mast base 104. In some aspects, wingsail 108 may rotate around the mast 106 via a wingsail rotational bearing 308 at the bottom of the wingsail and another bearing (not shown) at the top of the wingsail. This rotation may allow the wingsail 108 to adjust its angle to the wind, optimizing the lift generated by the wingsail 108 and improving the performance of the sailboat 100.

[0054] Mast 106 may also support adjustable tail sections 112 and 114 via a rigid tail support frame 110. The mast base motor 302, situated at the base of the mast, may operate in conjunction with the angle sensor 306, other sensors 322, and the controller 320 to adjust the wingsail's position by moving cable 304 in two different directions. During operation, mast base motor 302, under the direction of controller 320, may pull mast cable 304 in one of two directions with the aid of mast top pully 312. In response, mast cable 304 pulls on collar 310 in one of two directions (up/down in the figure), causing the collar 310 to slide up or down the mast 106. In response, collar 310 pulls on tail cable 316 in one of two directions (left/right in the figure), which applies a pivoting force to wingsail sections 112 and 114 with the aid of pullies 314A, 314B, and 318.

[0055] In some cases, the tail control mechanism may further comprise a series of pulleys, such as mast top pully 312, upper collar pully 314A, lower collar pully 314B, and adjustable tail pully 318. These pulleys may be configured to facilitate a change in direction of the force applied to the slidable collar 310 and the adjustable tail sections 112 and 114. In some aspects, a bearing internal to collar 310 may facilitate free rotation of the slidable collar 310 around the mast 106, allowing for smooth and unrestricted adjustment of the angle of the adjustable tail sections 112 and 114 even when the wingsail is rotated to different tacking positions.

[0056] In some cases, the self-trimming wingsail system may include a controller 320 configured to control the motor 302 based on sensor data to adjust the angle of the adjustable tail sections 112 and 114. The sensor data may include data related to the angle of attack of the wingsail 108, wind direction, and speed of the sailboat 100. This sensor data may be used to control the position of the adjustable tail sections 112 and 114, thereby adjusting the angle of attack of the wingsail 108 and improving the performance of the sailboat 100.

[0057] The controller 320 may include hardware such as a processor, memory, and a display having a graphical user interface. The processor may be configured to process the sensor data and generate control signals for the motor 302. The memory may be used to store the sensor data, control signals, and other data and software related to the operation of the self-trimming wingsail system. The display with a graphical user interface may provide a user-friendly interface for a user to monitor and control the operation of the self-trimming wingsail system.

[0058] In addition to the processor, memory, and display, the controller 320 may also include a transceiver for wirelessly receiving sensor data and instructions from other boats and land-based stations. The transceiver may be configured to communicate with the land-based stations using various wireless communication protocols. The received sensor data and instructions may be used by the processor to control the motor 302 and adjust the angle of the adjustable tail sections 112 and 114.

[0059] In addition, the controller 320 may also interface with smart devices for providing an improved user experience for controlling the sailboat. For example, a user may use a smart device, such as a smartphone or tablet, to remotely monitor and control the operation of the self-trimming wingsail system via the controller 320. The smart device may display real-time data related to the operation of the self-trimming wingsail system and allow the user to adjust the angle of the adjustable tail sections 112 and 114, change the tacking position of the wingsail 108, and perform other control actions. This feature may provide a convenient and efficient way for the user to control the sailboat, especially in autonomous wind-powered navigation scenarios.

[0060] Turning now to FIG. 3B, a perspective view of a wingsail mechanism 340 (similar to the wingsail mechanism in FIG. 3A) is depicted, illustrating the internal mechanical components and their interactions. The mast 106, which may be equipped with a mast top bearing 344, supports the wingsail frame and allows it to rotate around mast. In some aspects, the mast top bearing 344 may be implemented using a bearing or other rotational mechanism that allows for smooth and unrestricted rotation of the wingsail frame around the mast 106.

[0061] Surrounding the mast 106 may be a ring 310A, which allows a collar 310, equipped with bearings, to rotate around the mast 106. In some cases, the collar 310 may be configured to slide up or down the mast 106 in response to a force applied by a mast cable 304. This mast cable 304, which may be connected to the collar 310, may be pulled up or down the mast 106 by a motor 302 under the direction of a controller 320. The rotation of the motor 302 may cause a drive pully 302A to rotate, which imparts a force on the mast cable 304. As the collar 310 moves up or down the mast 106, it may pull on an adjustable tail cable 316, which imparts a rotational force on an adjustable tail pully 318.

[0062] Connected to the collar 310 are an upper collar pully 314A and a lower collar pully 314B, which facilitate the movement of the adjustable tail cable 316 in response to the up and down movement of the collar 310. In some aspects, the adjustable tail cable 316 may include a first tail cable attached to a first side of the collar 310 and a second cable attached to a second side of the collar 310 via pullies 348A, 348B, 350A and 350B. This configuration may allow for precise control of the angle of the adjustable tail sections 112 and 114, which in turn influences the angle of attack of the wingsail 108.

[0063] The rotation of the adjustable tail pully 318 may cause an adjustable tail 352 to rotate to a desired angle of attack. In general, a wind force acting on adjustable tail 352 imparts a lateral force on rigid frame 346 which causes rigid frame 346 (and the supported wingsail) to rotate around mast 106. As the wingsail tacks, the angle of the wingsail may be monitored by an angle sensor 306. In some cases, rigid frame 346 supports the mechanical components of the overall system including the wingsail 108, pullies, cables and adjustable tail 352. This rigid frame 346 may provide structural support for the wingsail 108 and adjustable tail 352 and may be mechanically attached to the wingsail 108 via a rigid frame structure.

[0064] As mentioned above, the rigid frame 346 provides structural support for the wingsail 108 and adjustable tail 352 and may be mechanically attached to the wingsail 108 via a rigid frame structure. This rigid frame 346 facilitates the transmission of wind force from the adjustable tail 352 to the wingsail 108, enabling the adjustment of the wingsail's angle of attack. It is noteworthy that the size and shape of the rigid frame 346 may vary depending on the structure of the wingsail 108 and the adjustable tail 352. The design of the rigid frame 346 may be not fixed and can be tailored to accommodate different designs and sizes of wingsails and tails. The size of the rigid frame 346, for instance, may be larger for larger wingsails to provide adequate support. Similarly, the shape of the rigid frame 346 may be designed to match the contour of the wingsail 108 and the adjustable tail 352, ensuring a secure and efficient connection between these components.

[0065] Furthermore, the variability in the size and shape of the rigid frame 346 allows for customization of the self-trimming wingsail system to suit different types of sailboats and sailing conditions. For instance, a sailboat designed for high-speed racing may require a wingsail with a specific shape and size, necessitating a corresponding rigid frame 346. Similarly, a sailboat designed for long-distance cruising may require a different wingsail design, and thus a different rigid frame 346. This flexibility in the design of the rigid frame 346 contributes to the versatility and adaptability of the self-trimming wingsail system, making it suitable for a wide range of sailing applications.

[0066] In the disclosed self-trimming wingsail system, many of the mechanical components may be housed internally within the wingsail body. This may include the slidable collar 310, the collar cable 304, the rigid frame 346, and the tail cable 316. Housing these components internally provides several advantages. Firstly, it protects these components from the harsh marine environment, reducing the risk of corrosion and wear. Secondly, it helps to maintain the aerodynamic efficiency of the wingsail by minimizing external protrusions. Lastly, it enhances the overall aesthetics of the sailboat by concealing the mechanical components of the self-trimming wingsail system.

[0067] However, it is worth noting that not all components of the self-trimming wingsail system are housed internally. Some components may be exposed to the elements when the situation demands. For instance, the adjustable tail sections 112 and 114, which are pivotal in controlling the angle of attack of the wingsail, are located externally on the tail support frame which may also be partially exposed to the elements. These tail sections and tail support frame are designed to withstand the marine environment and are robust enough to handle the wind forces acting upon them. Similarly, the mast 106, which supports the wingsail and the tail sections, may also be exposed to the elements. These external components are designed and constructed with materials that can withstand the harsh marine environment, ensuring their longevity and reliable operation.

[0068] In the embodiments described above, the tail control mechanism of the self-trimming wingsail system utilizes cables to transmit force and control the angle of the adjustable tail. However, it is to be understood that the present disclosure is not limited to the use of cables. In alternative embodiments, other types of mechanical linkages or transmission elements may be used to replace the cables.

[0069] In some examples, belts may be used instead of cables in the tail control mechanism. Belts can provide a strong and durable means of transmitting force from the motor to the slidable collar and from the collar to the adjustable tail. Belts can be particularly advantageous in applications where a high degree of precision is desired, as they can provide accurate and consistent transmission of force. Furthermore, belts can be less prone to stretching or slackening compared to cables, thereby maintaining a consistent tension and ensuring reliable operation of the tail control mechanism.

[0070] In other examples, chains may be used to replace the cables in the tail control mechanism. Chains, such as roller chains or link chains, can provide a robust and durable means of transmitting force. Chains can be particularly advantageous in applications where a high degree of strength and durability is desired, as they can withstand high loads and harsh marine environments. Furthermore, chains can be less prone to wear and tear compared to cables, thereby enhancing the longevity and reliability of the tail control mechanism.

[0071] In yet other embodiments, other types of mechanical linkages or transmission elements may be used to replace the cables in the tail control mechanism. These may include, but are not limited to, rods, shafts, gears, or any other suitable mechanical elements that can transmit force from the motor to the slidable collar and from the collar to the adjustable tail. The choice of the specific type of mechanical linkage or transmission element may depend on various factors, such as the specific requirements of the sailboat, the desired level of precision and control, the expected load and environmental conditions, and other relevant factors.

[0072] Referring now to FIG. 4A, a process 400 for actuating a wingsail using a motor control mechanism is depicted. The steps generally include step 402 controlling the motor, step 404 collar sliding up/down the mast, step 406 collar pulling on tail cable, and step 408 motor controlled to maintain angle of attack. The process begins with step 402, where a motor control mechanism is operated. This operation can be initiated either manually by a user or automatically based on sensor data. The motor, in response to the control mechanism, pulls on a mast cable in a specific direction to achieve a desired angle of attack of the wingsail. In step 404, the force exerted by the motor on the mast cable causes a collar, which may be connected to the motor via the mast cable, to move along the mast. The collar may be designed to slide up or down the mast in response to the direction in which the mast cable is pulled by the motor. Following this, in step 406, the movement of the collar results in the collar pulling on a tail cable. The tail cable may be connected to the collar and an adjustable tail of the wingsail. As the collar moves, it pulls the tail cable, which in turn causes the tail to pivot in a specific direction. This pivoting of the tail translates the wind force into a rotational force on the wingsail, which may be mounted on the mast and may be designed to rotate freely around the mast. Then, in step 408, the motor adjusts the position of the tail to maintain the desired angle of attack of the wingsail. This adjustment may be controlled by the motor, which operates under the direction of a controller. The controller can use sensor data or other inputs to determine the appropriate adjustments to the tail's position. This series of mechanical linkages and movements allows for precise control of the wingsail's angle of attack, optimizing the performance of the sailboat.

[0073] Turning now to FIG. 4B, a process 440 for adjusting the angle of attack of a wingsail on an autonomous sailboat is depicted. Process 440 generally includes step 442 detecting sail relevant data, step 444 using the detected data to determine position of the tail, step 446 determining if the desired angle of attack of the wingsail achieved, step 448 maintaining the collar position and step 450 adjusting the collar position. The process 440 may start with a sensor detection step 442, where one or more sensors may detect parameters such as the angle of attack of the wingsail, wind direction, and speed of the sailboat. These sensors may include, but are not limited to, anemometers, wind vanes, speedometers, angle sensors and other suitable sensors for detecting wind and boat conditions. Following the sensor detection step 442, the process 440 may proceed to a controller processing step 444. In some cases, a controller, such as controller 320, may utilize the sensor data to determine the position of the tail to achieve the desired angle of attack of the wingsail. The controller 320 may be configured to process the sensor data and generate control signals for adjusting the position of the tail based on the sensor data and predetermined sailing parameters. Next, the process 440 may involve an angle of a step 446 for determining if the desired angle of attack of the wingsail achieved. At this decision point, it may be determined whether the desired angle of attack of the wingsail has been achieved. This determination may be based on the sensor data, the control signals generated by the controller 320, and other relevant factors. If the desired angle of attack of the wingsail has been achieved, the process 440 may move to a collar position maintenance action step 448 to maintain the current collar position. In some aspects, the collar, such as collar 310, may be maintained in its current position along the mast, such as mast 106, to maintain the current angle of attack of the wingsail. If the desired angle of attack of the wingsail has not been achieved at the angle of attack decision step 446, the process 440 may proceed to a collar adjustment step 450. In some cases, the controller 320 may control a motor, such as electric motor 302, to adjust the collar, which in turn adjusts the position of the tail. This adjustment may translate wind force to rotational force on the wingsail, thereby achieving the desired angle of attack. The collar adjustment step 450 may involve moving the collar up or down the mast in response to the control signals generated by the controller 320.

[0074] The self-trimming wingsail system disclosed herein may be designed with a keen focus on aesthetics and aerodynamics. The wingsail and the adjustable tail sections are shaped to increase the lift generated by the wind, thereby improving the speed and stability of the sailboat. The sleek and streamlined design of the wingsail and tail sections not just enhances the aesthetic appeal of the sailboat, but also contributes to its aerodynamic efficiency. One of the notable features of the self-trimming wingsail system may be the internal housing of the majority of the mechanical components. The slidable collar, the collar cable, the rigid frame, and the tail cable are housed internally within the wingsail body. This internal housing of components not just protects them from the harsh marine environment, but also helps maintain the aerodynamic efficiency of the wingsail by minimizing external protrusions. Furthermore, it enhances the overall aesthetics of the sailboat by concealing the mechanical components of the self-trimming wingsail system. This results in a clean, streamlined appearance that may be visually pleasing.

[0075] The self-trimming wingsail system may be also designed to be energy efficient, particularly in the operation of the tail control mechanism. The tail control mechanism, which includes a motor and a slidable collar connected via a collar cable and a tail cable, may be designed to adjust the angle of the adjustable tail of the wingsail. This adjustment may be achieved by transmitting a linear force from the slidable collar to the adjustable tail via the tail cable. The force applied by the motor to move the slidable collar may be relatively small, which results in low power consumption. The self-trimming wingsail system allows the wind force acting on the adjusted tail to exert a force on the wingsail via a rigid frame, causing the wingsail to adjust its angle of attack. This process leverages the natural wind energy to adjust the wingsail, thereby reducing the reliance on the motor and further contributing to the energy efficiency of the system.

[0076] The disclosed self-trimming wingsail system may be beneficial to a wide range of boating scenarios. For sailboats, including autonomous sailboats, the self-trimming wingsail system can provide improved aerodynamic efficiency, precise control, and enhanced performance, especially in varying wind conditions. The system's ability to automatically adjust the angle of attack of the wingsail can be particularly advantageous for autonomous sailboats, reducing the complexity of sail handling and navigation.

[0077] For motorized boats, the self-trimming wingsail system can serve as an auxiliary propulsion system, providing fuel-saving benefits. When the wind conditions are favorable, the motorized boat can switch to the self-trimming wingsail system for propulsion, saving fuel and reducing emissions. Furthermore, the self-trimming wingsail system can be beneficial for hybrid boats that use both sails and engines for propulsion, offering a versatile and efficient solution for various sailing scenarios.

[0078] While the foregoing is directed to example embodiments described herein, other and further example embodiments may be devised without departing from the basic scope thereof. For example, aspects of the present disclosure may be implemented in hardware or software or a combination of hardware and software. One example embodiment described herein may be implemented as a program product for use with a computer system. The program(s) of the program product defines functions of the example embodiments (including the methods described herein) and may be contained on a variety of computer-readable storage media. Illustrative computer-readable storage media include, but are not limited to: (i) non-writable storage media (e.g., read-only memory (ROM) devices within a computer, such as CD-ROM disks readably by a CD-ROM drive, flash memory, ROM chips, or any type of solid-state non-volatile memory) on which information is permanently stored; and (ii) writable storage media (e.g., floppy disks within a diskette drive or hard-disk drive or any type of solid-state random-access memory) on which alterable information is stored. Such computer-readable storage media, when carrying computer-readable instructions that direct the functions of the disclosed example embodiments, are example embodiments of the present disclosure.

[0079] It will be appreciated by those skilled in the art that the preceding examples are exemplary and not limiting. It is intended that all permutations, enhancements, equivalents, and improvements thereto are apparent to those skilled in the art upon a reading of the specification and a study of the drawings are included within the true spirit and scope of the present disclosure. It is therefore intended that the following appended claims include all such modifications, permutations, and equivalents as fall within the true spirit and scope of these teachings.