A system and method for determining a flying shape of a sail

Abstract

A system (400) for determining a first flying shape (152A, 252A, 352A, 150B) of a sail (150A, 150B) of a sailboat (140), the system comprising a set of sail sensors, wherein each sail sensor (110, 110A, 210, 310) of the set of sail sensors is attached on respective locations on the sail; a reference sensor (112, 212, 312, 412) attached to a hull (142) of the sailboat; a processor (114, 4128) configured to receive orientation data from each sail sensor and the reference sensor; apply an orientation filter to the orientation data to estimate the orientation of each of the sail sensors relative to the reference sensor; calculate normal vectors at each respective location on the sail based on the estimated orientation of each sail sensor; interpolate the normal vectors to create a continuous field of normal vectors across the sail's surface; determine the first flying shape of the sail using the interpolated normal vectors.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of sailboat dynamics, specifically to systems and methods for measuring and determining the flying shape and orientation of a sail in relation to the sailboat, utilizing a network of sensors to optimize sail performance.BACKGROUND

[0002] In the field of sailboat dynamics, the accurate measurement and analysis of sail shape and orientation are critical factors that significantly influence the performance of a sailboat. The shape of a sail, commonly referred to as the "flying shape," directly impacts the aerodynamic efficiency of the sail and, consequently, the speed and maneuverability of the sailboat. Sailors and sailing teams often seek to optimize sail shapes to enhance performance, particularly in competitive sailing environments. The term flying shape generally refers to a shape of the sail when the sail is used and captures wind.

[0003] Typically, the measurement of sail shape has been approached through various methods, with one of the most prominent being the use of camera-based systems. These systems utilize cameras mounted at specific locations on the boat to capture images of the sail, which are then processed to determine the sail shape. However, this method presents several challenges. The effectiveness of camera-based systems is highly dependent on environmental conditions, such as light and moisture, which can obscure the lens and distort the data. Also camera-based systems might not be usable for example during night or foggy conditions. Additionally, finding an optimal mounting position for the cameras that provides an unobstructed view of the sail is often difficult, limiting the accuracy of the measurements.

[0004] Therefore, in light of the foregoing discussion, there is a need to overcome the aforementioned limitations to enhance the precision and reliability of sail shape measurement systems. A comprehensive solution is required that can provide accurate real-time data on sail shape and orientation, independent of external environmental conditions, to improve the overall performance of the sailboat.SUMMARY

[0005] The aim of the present disclosure is to provide a system and a method to solve the technical problem of accurately determining a flying shape of a sail on a sailboat, which is important for optimizing sail performance under various sailing conditions. The precise measurement of the sail's shape and orientation directly impacts the aerodynamic efficiency of the sail, influencing the speed and maneuverability of the sailboat. The present disclosure addresses the limitations of existing methods by offering a more reliable and accurate solution.

[0006] The aim of the disclosure is achieved by a system and a method for determining a first flying shape of a sail, comprising a set of sail sensors attached at specific locations on the sail, a reference sensor mounted on the hull of the sailboat, and a processor configured to receive orientation data from each sail sensor and the reference sensor. The processor applies an orientation filter to estimate the orientation of each sail sensor relative to the reference sensor, calculates normal vectors at each respective location on the sail based on the estimated orientation, interpolates these vectors to create a continuous field across the sail's surface, and determines the first flying shape of the sail using the interpolated normal vectors, as defined in the appended independent claims to which reference is made. Advantageous features are set out in the appended dependent claims.

[0007] The embodiments of the present disclosure substantially enable the improvement of sail shape measurement accuracy by minimizing dependency on external factors such as light and moisture conditions, which often compromise the effectiveness of traditional camera-based methods. This system provides more reliable real-time data, allowing sailors to optimize sail performance effectively. Additional aspects, advantages, features, and objects of the present disclosure will be made apparent from the drawings and the detailed description of the illustrative embodiments constructed in conjunction with the appended claims that follow.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the embodiments of the disclosure are shown in the drawings, with references to the following diagrams wherein: FIG. 1A illustrates a system showing the overall configuration; FIG. 1B is a perspective view of the sailboat as seen from a top according to an embodiment; FIG. 1C is perspective view of the sailboat which is leaning to stern side as seen from the aft; FIG. 2A is an illustration horizontal cross section of a first flying shape and a set of sail sensors; FIG. 2B is an illustration of horizontal cross section of a second flying shape and a set of sail sensors; FIG. 3A is an illustration of vertical cross section of a first flying shape and a set of sail sensors; FIG. 3B is an illustration of vertical cross section of a second flying shape and a set of sail sensors and FIG. 4 is an illustration of a system components according to one embodiment. DETAILED DESCRIPTION OF EMBODIMENTS

[0009] The following detailed description illustrates embodiments of the present disclosure and ways in which they can be implemented. The present disclosure provides a system, method, software product, and sail for determining the flying shape of a sail on a sailboat. This system is designed to overcome the limitations of existing methods by providing accurate, real-time data that is independent of environmental conditions such as light and moisture, which typically affect the performance of traditional measurement systems.

[0010] In a first aspect, the present disclosure provides a system for determining a first flying shape of a sail of a sailboat, the system comprising a set of sail sensors, wherein each sail sensor of the set of sail sensors are attached on respective locations on the sail; a reference sensor attached to a hull of the sailboat; a processor configured to: receive orientation data from each sail sensor and the reference sensor; apply an orientation filter to the orientation data to estimate the orientation of each of the sail sensors relative to the reference sensor; calculate normal vectors at each respective location on the sail based on the estimated orientation of each sail sensor; interpolate the normal vectors to create a continuous field of normal vectors across the sail's surface; determine the first flying shape of the sail using the interpolated normal vectors.

[0011] According to one embodiment an orientation filter is applied to sensor data to estimate the orientation of each sail sensor relative to the reference sensor. The orientation filters inputs are readings from a single sail sensor or a reference sensor (lx(acc+mag+gyr)) and the filters output is the orientation of the sensor in Earths reference frame, known as absolute orientation. Each sensor comprises typically three individual sensors. Accelerometer sensor, magnetometer sensor and gyroscope sensor. The said three individual sensors are preferably 3-axis sensors. All of the three individual sensors provide the sensor data.

[0012] The system includes a set of sail sensors strategically attached at specific locations across the sail to capture the orientation data at various points on the sail's surface. As an example, some of the sensors could be placed parallel to battens of the sail. There could be for example 2, 3, 4, 5 or 6 sail sensors in a row (along each of the batten). In general, the set of sail sensors are attached as a grid along sail surface. Number of sensors depend on the size of the sail. Large sail could have several, such as tens of sensors. Distance between the sensors could be arranged as equal distance or the distance can be for example expected curvature of the sail (more expected curvature closer the sensors to each other's). Some of the sensors from the set of sail sensors are preferably arranged close to leech of the sails or at clew of main sail or jib. The respective location information is stored to the system after attaching the sensors. The reference sensor is mounted on the sailboat's hull, providing a fixed point of reference for determining the absolute orientation of the sailboat and the relative orientation of each sail sensor to the sailboat.

[0013] The processor is configured to receive orientation data from each sail sensor and the reference sensor. This orientation data typically includes measurements from accelerometers, gyroscopes, and magnetometers, which are integral components of both the sail sensors and the reference sensor. The processor applies an orientation filter to the received data to estimate the orientation of each sail sensor relative to the reference sensor. In general sampling rate can be arbitrary such as 10, 20, 50, 100Hz or higher depending on need.

[0014] This estimation is crucial as it provides a clear understanding of how each portion of the sail is positioned in relation to the boat and other portions of the sail, directly influencing the aerodynamic properties of the sail.

[0015] To calculate the normal vectors at each respective location on the sail, the processor utilizes the estimated orientation data. A normal vector is a vector perpendicular to the surface at a given point, representing the local orientation of the sail at that location. According to embodiments a normal vector is determined for each sail sensor. Since we know the orientation (and respective location) of each of the sail sensors in respect to the sail (due to attaching those in respective locations) we can collect a set of normal vectors in respect to various points on the sail.

[0016] Following the calculation of the normal vectors, the processor interpolates these vectors to generate a continuous field of normal vectors across the sail's surface. Interpolation, a mathematical technique, is employed to estimate unknown values between known data points. In this system, interpolation creates a smooth and continuous representation of the sail's shape, even at locations where no sensors are directly positioned. This continuous field offers a comprehensive view of the sail's shape, enabling precise analysis and adjustments. Optionally, portions of the sail's flying shape might be determined by extrapolation.

[0017] Purpose of the interpolation process is to smoothly blend the discrete (at respective locations of the sail sensors) normal vectors. This way a normal vector can be calculated at every (needed) point on the surface of the sail by averaging or interpolating the vectors from surrounding points. The resulting continuous normal vector field provides each point on the surface with a well-defined and smoothly varying normal vector, which offers a coherent representation of the surface's orientation.

[0018] As a note, however, in practical calculations, this continuous field is not genuinely continuous but is instead represented by a discretized approximation, where a specific pitch or spacing exists between points. This pitch defines the distance between the points on the surface where normal vectors are calculated or interpolated. While the objective is to approximate a continuous field, the inherent discrete nature of computational methods dictates that the field is sampled only at specific intervals. The accuracy and smoothness of the resulting field are dependent on the density of these points: a finer pitch (smaller spacing) yields a more accurate and smoother approximation of the continuous field, whereas a coarser pitch (larger spacing) may result in noticeable gaps or approximations. This discretization is a necessary compromise in computational methods to balance precision with computational efficiency. For instance, the pitch between the points can be, for example, 1 mm, 5 mm, 1 cm, 10 cm, 30 cm, etc. In some embodiments, the pitch may vary depending on the curvature of the sail surface in the vicinity of the sail sensor.

[0019] Optionally and in addition to interpolating, a part of the flying shape (such as area between a sensor and mast) of the sail could be determined by extrapolating.

[0020] In alternative embodiment a controller of the sail sensors is configured to determine normal in respect to each sail sensor. The normal values can be sent to onboard computer (reference sensors + processor unit) in which then actual flying shape is determined using information from each of the sail sensors. Indeed division of "intelligence" can be arbitrary. In some embodiments the sail sensors can merely provide raw sensor data (such as accelerometer info, magnetometer info and / or gyroscope info) via communication interface to processor. The processor determines from the provided raw sensor data needed orientations, normal vectors and finally the flying shape. In some embodiments the sail sensors can have more intelligence build in those and those could provide, as orientation data, normal of each sensor as an example. In one embodiment some or all of the collected data is processed by processor which is located in cloud.

[0021] The system then determines the first flying shape of the sail using the interpolated normal vectors. The "flying shape" refers to representation of the actual shape that the sail takes when deployed and subjected to wind forces. This shape is critical for understanding how the sail is performing and how it can be adjusted to optimize performance. By using the interpolated normal vectors (of created continuous field of normal vectors), the system can accurately model the entire sail and provide detailed information about its shape.

[0022] Optionally, the sail sensor comprises an accelerometer, a gyroscope, and a magnetometer, and the orientation data comprises measurements from the accelerometer, the gyroscope, and the magnetometer of the sail sensor. These sensors can by understood as "sub sensors" of the sail sensor.). In one embodiment the sail sensor comprises the accelerometer and the magnetometer. These (sub) sensors work together to provide a comprehensive picture of the sail's movement and orientation. The accelerometer measures acceleration forces, which can indicate the motion of the sail , providing data on how the sail is reacting to changes in wind speed and direction . Particularly the accelerometer sensor can be used to determine direction towards earth i.e. towards earth's gravitational field. The gyroscope measures rotational movement, which helps in understanding how the sail is tilting or pivoting, giving insights into the dynamic behavior of the sail. The magnetometer measures the magnetic field, allowing the system to determine the sail's orientation relative to the Earth's magnetic field. The integration of these sensors in the orientation filter provides the absolute orientation which acts as the base for further calculation related to sail shape. The accelerometer sensor is preferably a three axis sensor measuring acceleration in respect to x, y and z directions. The magnetometer sensor can is preferably a three axis sensor measuring direction of magnetic field in respect to x, y and z directions. The gyroscope sensor is preferably a three axis sensor measuring direction of rotations in respect to x, y and z directions. Benefit of 3 axis sensor is that it enables calculation of of absolute orientation (i.e. in respect to Earth for example). Indeed to make the calculation all the sensor should preferably have at least three axes which orientations to each other are known and which aren't on the same plane. Preferably the sensor axes are perpendicular to each others. The sail sensors provide, preferably, the orientation data (sensor data) over wireless interface such as low power Bluetooth to the processor. Alternatively mesh network can be utilized to get data from upper parts of the sail (top of the mast) reliable to the processor.

[0023] This combination of measurements ensures that the system can provide a accurate and reliable estimation of the sail's orientation and shape, even under varying environmental conditions.

[0024] The use of these sensors allows the system to continuously monitor the sail's behavior, providing real-time data that can be used to adjust the sail's shape for optimal performance. For instance, the system can detect when the sail is not performing optimally due to excessive twist or deformation and suggest adjustments to correct this. This capability is particularly valuable in competitive sailing, where small adjustments can make a significant difference in performance.

[0025] In general magnetometer of the sail sensor provides a vector component which is parallel to earth (sea surface). The accelerometer provides a vector component of the sail sensor which is perpendicular to earth (sea surface). These vectors can be used to calculate normal vector for the sail sensor.

[0026] As an example, the accelerometer and magnetometer readings are used to determine the orientation (of each point in which the sail sensor is attached) in a static setting. In practical use case the sails are almost never static, so we also need gyroscope, to compensate in dynamic situations. In practice in dynamic conditions accelerometer is not able to provide direction of the Earth gravitational field as it is disturbed by additional accelerations and movements. Indeed, when sail is for example flapping acceleration caused by the rapid movement can be several times larger than the gravitational attraction (G) of Earth. Gyroscope can be used out to be factor those movements (to a degree) out from the reading and thus normal vectors can be determined more precisely.

[0027] Optionally, the reference sensor comprises an accelerometer, a gyroscope, and a magnetometer, and the orientation data comprises measurements from the accelerometer, the gyroscope, and the magnetometer of the reference sensors.). The reference sensor is mounted on the hull of the sailboat, providing a stable and fixed point of reference against which the orientation of the sail sensors can be compared. This sensor setup ensures that the system can accurately determine the relative orientation of the sail to the boat, which is critical for optimizing the sail's angle of attack and overall aerodynamic efficiency.

[0028] By using a reference sensor that includes an accelerometer, gyroscope, and magnetometer, the system can account for the motion of the boat itself, ensuring that the orientation data from the sail sensors is interpreted correctly.

[0029] Optionally, the processor is further configured to: receive, at a first moment of time, a first set of data from one or more sailboat sensors and associate the received first set of data with the first flying shape. The sailboat sensors might include instruments that measure speed, wind angle, wind speed, and other performance-related metrics. By associating this performance data with the flying shape of the sail, the system can provide a detailed analysis of how different sail shapes affect the sailboat's performance.

[0030] This functionality enables the system to track how specific sail shapes correlate with the boat's speed, stability, and maneuverability under various weather conditions . For example, the system could identify that a particular sail shape consistently results in higher speeds when sailing close to the wind. Sailors can then adjust their sails to replicate this shape in similar conditions, thereby enhancing performance. Additionally, this data can be stored and reviewed after sailing sessions to help teams refine their sail configurations and strategies for future races.

[0031] Optionally, the processor is further configured to: receive, at a second moment of time, a second set of data from the one or more sailboat sensors, wherein the second moment of time is after the first moment of time; determine a second flying shape associated with the second moment of time; compare the first set of data and the second set of data and if based on the comparison boat performance indicator was higher at the first movement of time than at the second moment of time indicate with a user interface corrective actions related to the second flying shape. This capability allows the system to continuously monitor and compare the effectiveness of different sail shapes over time.

[0032] According to an embodiment, the determined flying shape (the first flying shape and / or the second flying shape) can be used to provide a set of data to at least one of: autopilot controlling a direction of the sailing boat, actuators of the sail, user interface of on-board computer. As an example, the set of data can be used to provide data related to steering of the boat as well as trimming of the sails. The set data can be used for rendering for a user (sailor or grew) the flying shape of the sail or it can be used to control for example autopilot of the sailing boat or for example automatically adjust sails. As an example, if the second flying shape could be corrected to same as the first flying shape by releasing mainsheet or sheet of the jib using actuator related to the sail. The set of data can be used also to indicate (over user interface) this to sailor or to automatic system.

[0033] By comparing performance data at different times, the system can identify when a change in the sail's shape has negatively impacted the boat's performance. For instance, if the boat's speed drops after the sail is adjusted, the system can analyze the shape and suggest corrective actions to restore optimal performance. This feature is particularly useful in real-time sailing situations, where conditions can change rapidly, and quick adjustments are necessary to maintain peak performance. As an example wind speed at the first moment of time was 5m / sec and true angle of the wind was 40 degrees. Speed of the boat towards wind was 4knots. A first flying shape is determined at said first moment of time. At the second moment of time (such as few minutes later or next day or next time sailing) wind speed and true angle are same. Theoretically now if the second flying shape is identical to the first flying shape the boat should travel towards wind with same 4knots. If as an example speed is 3knots this can be indicated to sailor. One way to indicate this is to show next to each others or as overlay images the first flying shape and the second flying shape and high light the differences. This way the sailor gets feedback on the second flying shape and can do adjustments to get it to same or similar as the first flying shape thus increasing the speed from 3knots to 4 knots.

[0034] Optionally, the boat performance indicator is based on at least one of: speed of the boat, close-haul angle of the boat, running speed, velocity made good to target, velocity made good to windward, wind adjusted speed of the boat. These performance indicators provide outline to assets the sailboat's effectiveness under different sailing conditions. In this regards the term "higher" in respect to the comparing boat performance indicator refers to any measurable parameter. As an example, performance is higher if the speed is higher. Another example performance is higher if close-haul angle is smaller.

[0035] For example, the "velocity made good to windward" is a critical metric in competitive sailing, as it measures how efficiently a boat is moving towards the wind, which is important during upwind legs of a race. By analyzing how the sail's shape affects these indicators, the system helps sailors fine-tune their sails to maximize efficiency and speed. This detailed performance analysis is invaluable for competitive sailors who need to optimize every aspect of their sailboat's setup.

[0036] Optionally, the set of sail sensors are attached to the sail by at least one: double sided tape, sewing pockets, attached to a batten of the sail, Velcro straps, and / or embedded in the sail. The method of attaching the sensors to the sail is crucial for ensuring that they remain securely in place while also minimizing any impact on the sail's aerodynamic properties.

[0037] Different attachment methods provide flexibility depending on the type of sail and the specific sailing conditions. For instance, embedding the sensors in the sail or attaching them to battens might be preferable for high-performance racing sails, where minimal drag and a streamlined profile are critical. In contrast, using Velcro straps or sewing pockets might be more suitable for sails used in less demanding conditions, where ease of attachment and removal are more important. The choice of attachment method also ensures that the sensors can be positioned precisely where needed to capture the most relevant data.

[0038] Optionally, the system comprises a boom orientation sensor to measure the orientation of the boom in respect to the hull and at least one of the sail sensors to determine the twist of a mainsail in respect to the boom. The twist of the sail refers to the difference in angle between the top and bottom of the sail, which affects how the sail interacts with the wind.

[0039] Measuring and controlling sail twist is critical for optimizing sail shape, particularly in varying wind conditions. Too much twist can lead to a loss of power, while too little can cause the sail to stall. By using a boom orientation sensor in conjunction with the sail sensors, the system can provide precise data on the twist of the sail, allowing sailors to make fine-tuned adjustments to achieve the ideal sail shape. This capability is especially important in races where wind conditions change frequently, and maintaining the optimal sail shape can be the difference between winning and losing.

[0040] In a second aspect, the present disclosure provides a method for determining a first flying shape of a sail of a sailboat, the method comprising receiving orientation data from sail sensors attached on respective locations on the sail and from a reference sensor attached on a hull of the sailing boat; applying an orientation filter to the orientation data to estimate the orientation of each of the sail sensors relative to the reference sensor; calculating normal vectors at each respective location on the sail based on the estimated orientation of each sail sensor; interpolating the normal vectors to create a continuous field of normal vectors across the sail's surface; determining the first flying shape of the sail using the interpolated normal vectors. In one embodiment the orientation filter employed in this method is particularly optimized for low-power and real-time applications. It achieves high accuracy in orientation estimation even with minimal computational resources, making it ideal for use in onboard sailing systems. One example of filter can be a quaternion filter representation ensures that the calculations remain robust and free from the limitations of traditional orientation estimation methods.

[0041] This method provides a structured process for accurately determining the sail's shape and orientation, enabling real-time adjustments and performance optimization.

[0042] This method ensures that critical data points across the sail's surface are captured and analyzed, allowing for the accurate reconstruction of the sail's flying shape. By applying this method, sailors can continuously monitor and adjust the sail's shape to maintain optimal performance, even in changing wind conditions. The ability to interpolate normal vectors ensures that even areas of the sail that are not directly monitored by sensors are sufficiently represented in the overall shape analysis. It has been found out surprisingly that even a small number of sensors (say 3-5 per row and number of rows such as row per 1-5 meter of the sails vertical height) provide information for sailor which outperforms prior art ways of determining the flying shape.

[0043] Optionally, the method further comprises collecting boat sensor data to determine a boat performance indicator for a first moment of time and associating the respective first flying shape of the sail to the determined boat performance indicator. This step allows the method to link specific sail shapes to measurable performance outcomes, providing valuable feedback for sailors looking to optimize their sail configurations.

[0044] By associating the sail shape with performance indicators, sailors can better understand the impact of their adjustments and make data-driven decisions on how to set their sails for different conditions. This method not only enhances real-time decision-making but also provides valuable insights for post-race analysis, helping teams to refine their strategies and sail configurations for future competitions.

[0045] Optionally, the method further comprises collecting boat sensor data to determine a boat performance indicator for a second moment of time, which the second moment of time is after a first moment of time; determining a second flying shape associated with the second moment of time; comparing the boat performance indicator of the first moment of time with the boat performance of the second moment; if based on the comparison boat performance indicator was higher at the first movement of time than at the second moment of time indicate with a user interface corrective actions related to the second flying shape. This process helps sailors continuously improve their sail configurations by providing real-time feedback and suggestions based on past performance.

[0046] The ability to compare performance over time is important for understanding how changes in sail shape affect overall sailing efficiency. This method provides a systematic approach to evaluating sail adjustments, allowing for continuous improvement. The feedback provided by the system can be used to make immediate corrections during a race or to inform future adjustments in similar conditions.

[0047] In a third aspect, the present disclosure provides a software product for execution on a computer system, wherein the software product is configured to execute the above discussed method. This software product facilitates the implementation of the method by providing the necessary algorithms and user interface for processing the data, calculating the sail's shape, and offering performance feedback.

[0048] The software product is designed to be used on various computing devices, from onboard computers to tablets or smartphones, allowing for flexible deployment in different sailing environments. The user interface is intuitive, providing clear visualizations of the sail's shape and performance metrics, making it easier for sailors to interpret the data and make informed decisions. The software also supports data storage and analysis, enabling teams to review and learn from past performances.

[0049] In a fourth aspect, the present disclosure provides a sail, comprising a set of sail sensors attached to the sail at determined locations. This sail is designed to integrate seamlessly with the system, providing accurate and reliable data on the sail's shape and orientation.

[0050] The integration of sensors directly into the sail fabric ensures that the data collected is precise and relevant, reflecting the actual conditions experienced by the sail. This integration is particularly important for high-performance racing sails, where even small inaccuracies in shape can lead to significant performance losses. By incorporating the sensors into the sail, the system ensures that all data is directly related to the sail's performance, providing the most accurate possible analysis.

[0051] Optionally, each sail sensor of the set of sail sensors comprises, a sub sensor such as: an accelerometer, a gyroscope and / or a magnetometer, and a communication interface to provide data from the accelerometer, the gyroscope and the magnetometer to a computer system. These sensors work together to provide comprehensive data on the sail's movement and orientation, which is then processed by the system to determine the sail's flying shape.

[0052] The communication interface ensures that data from the sail sensors is transmitted reliably and efficiently to the central processor, allowing for real-time analysis and adjustments. This setup is critical for competitive sailing, where decisions need to be made quickly based on the most current data. The combination of these sensors provides a full picture of the sail's behavior, from its overall shape to its response to dynamic forces like wind and boat movement.

[0053] The present disclosure, through its various aspects, provides a detailed and robust solution for determining and optimizing the flying shape of sails on sailboats. By leveraging advanced sensor technology and sophisticated data processing methods, this system enables sailors to achieve better performance and efficiency in a wide range of sailing conditions.DETAILED DESCRIPTION OF THE DRAWINGS

[0054] Referring to FIG. 1A, illustrated is an embodiment of a system designed to determine the first flying shape 152A, 150B of sails 150A (main sail) and 150B (jib) of a sailboat 140. The sailboat 140 is equipped with multiple sensors, including sail sensors 110, 110A, 110B which are attached to various respective locations on the sails 150A, 150B. Additionally, sailboat sensors 120, 122, 124 are positioned on different parts of the sailboat 140 to collect data regarding the boat's orientation and movement. In figure sailboat sensor 120 is log for measuring speed of the boat, sensor 122 is wind direction and speed sensor, sensor 124 is a global positioning sensor. A boom orientation sensor 130 is attached to the boom to measure its orientation in relation to the hull 142 and at least one of the sail sensors 110B to determine the twist of a main sail 150A in respect to the boom.

[0055] The system comprises a reference sensor 112 mounted on the hull 142 of the sailboat 140. This reference sensor 112 provides a stable reference point for the orientation data collected by the sail sensors 110 110A. The processor 114, which is part of the onboard computer 116, receives and processes the orientation data to calculate the normal vectors at various points on the sails. The processor 114 of the onboard computer 116 uses these normal vectors to determine the first flying shape 152A of the sail 150A, optimizing the sail's configuration for better performance. As an example, the onboard computer can be dedicated "flying shape" determining computer which houses the processor 114 dedicated for flying shape calculations as well as the reference sensors. Alternatively, the onboard computer can be calculation unit for other tasks as well. In one embodiment the onboard computer could be a navigation computer. The sail sensors provide, in given example, the orientation data to the processor wirelessly.

[0056] Referring to FIG. 1B, the figure illustrates the system in perspective (cross section A-A of the figure 1A), focusing on the relationships and structural configuration of the sensors and components involved. The sail sensors 110, 110A, are attached to the sails. As an example of sailboat sensor, a sailboat sensor (GPS) 124 is attached to the sailboats deck. The reference sensor 112 is securely mounted on the hull 142 inside the onboard computer 116, providing a consistent reference for the data collected by the sail sensors. In some embodiments the GPS sensor can be part of the onboard computer 116.

[0057] The boom orientation sensor 130 is illustrated in its position relative to the sailboat's hull 142 and at least one of the sail sensors to determine the twist of a main sail in respect to the boom, highlighting its role in measuring the boom's orientation for determining twist of the sail. The onboard computer 116, which includes the processor 114, is responsible for processing the data from the sensors to determine the flying shape of the sail. This configuration ensures that the system can accurately monitor and adjust the sails for optimal performance. In the figure true wind angle (TWA) and apparent wind angle (AWA) are presented in respect to direction of the sailing boat 142. Also orientation (direction) of the sailing boat in respect to north (N) is illustrated.

[0058] Referring to FIG. 1C, illustrated is a view of the system in a perspective view (cross section B-B of the figure 1B), focusing on the structural and functional relationships between the mast 160, the onboard computer 116, and the sensors. The sail sensor 110 is shown in its attached positions on the sails, with the mast 160 providing the structural support necessary for the sails to function effectively. The hull 142 is depicted as the foundation where the reference sensor is mounted, providing the stable point of reference needed for accurate orientation data. The onboard computer 116, which processes the data from the sail sensors and the reference sensor, calculates the normal vectors and interpolates these to determine the first flying shape of the sail. This perspective view highlights the integration of the mast 160 and the onboard computer 116 into the overall system, demonstrating how the components work together to optimize sail performance. As an example accelerator sensor reading of the reference sensor in given example figure can be used to determine how many degrees the boat tilts due to wind.

[0059] Referring to FIG. 2A, illustrated is the sensors attached to the sail, where a different set of sail sensors 210 is used to determine the first flying shape 252A of a sail. The sail sensors 210 are positioned at different locations on the sail, and they work with the processor to calculate the normal vectors and interpolate them to create a continuous field across the sail's surface. The normal vector 270, derived from the orientation data provided by the sail sensors 210, is used to determine the first flying shape 252A. This figure illustrates the flexibility of the system in accommodating various sensor configurations while maintaining accurate measurements and optimal sail performance.

[0060] Referring to FIG. 2B, illustrated is the sensors attached to the sail in which a reference sensor 212 is attached to the hull, similar to the setup shown in previous figures. The reference sensor 212 provides a stable reference point for the system to compare the orientation data from the sail sensors. The processor uses this data to determine the second flying shape 252B of the sail. This figure underscores the importance of having a reliable reference sensor 212 to ensure the accuracy of the system's calculations. The relationship between the sail sensors and the reference sensor 212 is crucial for optimizing the sail's performance by adjusting its flying shape in real time.

[0061] In figures 2A and 2B is illustrated sensor reading from magnetometer of the sail sensor. Indeed, the magnetometer reading can provide a vector component which is parallel to sea surface. The reference sensors (magnetic reading) can be used to calibrate this.

[0062] Referring to FIG. 3A and 3B, illustrated is an embodiment of the system, where sail sensors 310 are attached to the sail at different locations in respect to vertical direction of the mast. A reference sensor 312 is mounted on the hull to provide a reference for the orientation data collected by the sail sensors 310. The processor, in conjunction with the onboard computer, calculates the normal vectors based on this data to determine the first flying shape 352A and a second flying shape 352B of the sail. A direction of the normal vector 370 is indicated in figures. The FIG 3A is an illustration of situation in which the sailing boat is not tilting. In FIG 3B the sailing boat is tiling angle a due to wind. It can be seen that first flying shape is different from the second flying shape in the presented example. Refence sensor reading is used to detect tiling. This information is used by orientation filter to estimate the orientations of each sail sensors.

[0063] In figures 3A and 3B is illustrated sensor reading from accelerometer sensor of the sail sensor. Indeed the accelerometer readings can provide a vector component which is perpendicular to the sea surface. The reference sensors (accelerator reading) can be used to calibrate this.

[0064] Together the vector component associated with magnetic sensor and the vector component associated with the accelerometer sensor can be used to determine normal vector for each of the sail sensors.

[0065] The sail sensor also comprise gyroscope. Role of the gyroscope is to provide filtering information to make reading of normal more accurate. As an example, if gyroscope shows lots of movements at given moment of time this can be taken in consideration when selecting datapoints for flying sail shape determination.

[0066] Referring to FIG. 4, illustrated is the system 400, showcasing the components and their interactions. The system comprises a sails sensor 410, which houses the accelerometer 4102, magnetometer 4104, gyroscope 4106, and communication interface 4100. The accelerometer, magnetometer and gyroscope are preferably 3-axis sensors. The sail sensor 410 comprises also a power source. As an example communication interface 4100 can be Bluetooth interface for sending data from the sensors to other parts of the system. In alternative / additional embodiment the sail sensor 410 can include also a processor / controller for determining locally the orientation (direction of normal) for the sail sensor. These sail sensors collect detailed orientation data. The data is provided via the communication interface 4100 to the onboard computer 416 via communication interface 4120 of the onboard computer 416. The data is processed by the processor 4128 of the onboard computer 416. The onboard computer 416 comprises reference sensor 412. The reference sensor 412 comprises accelerometer 4122, gyroscope 4124, and magnetometer 4126, to provide the necessary reference point for the system. The accelerometer, magnetometer and gyroscope are preferably 3-axis sensors. The onboard computer 412 processes the data from these sensors to determine the first flying shape of the sail. The onboard computer 412 can be connected to a boat network482 that connects all the components. The system can be used via a user interface 480. The user interface can be used to provide feedback to the sailor and grew. In one example embodiment the user interface 480 is onboard navigation equipment, in one example the user interface 480 can be part of the onboard computer. In one example the user interface 480 can be implemented in smart phone or tablet computer. Wireless communication modules 4100, 4120 ensure that data is seamlessly transmitted between the sensors and the onboard computer (thus the processor). The system also includes sailboat sensors 420, 422, 424, which are positioned on various parts of the sailboat to monitor additional parameters like boat speed, angle, and environmental conditions. These sensors provide data that can be used for the overall performance assessment of the sailboat. A boat network 482 connects all these components, facilitating seamless communication across the system. Example of the boat network in National Maritime Electronics Association (NMEA) based network. The user interface 480 provides real-time feedback to the operator, enabling them to make informed adjustments. Wireless communication modules 4100, 4120 ensure the smooth transmission of data between the sensors and the onboard computer. In one example embodiment the processor (thus the onboard computer) can send via the boat network commands to various actuators of the boat such as autopilot depending on determined flying shape of the sail.

Examples

Embodiment Construction

[0009]The following detailed description illustrates embodiments of the present disclosure and ways in which they can be implemented. The present disclosure provides a system, method, software product, and sail for determining the flying shape of a sail on a sailboat. This system is designed to overcome the limitations of existing methods by providing accurate, real-time data that is independent of environmental conditions such as light and moisture, which typically affect the performance of traditional measurement systems.

[0010]In a first aspect, the present disclosure provides a system for determining a first flying shape of a sail of a sailboat, the system comprising a set of sail sensors, wherein each sail sensor of the set of sail sensors are attached on respective locations on the sail; a reference sensor attached to a hull of the sailboat; a processor configured to: receive orientation data from each sail sensor and the reference sensor; apply an orientation filter to the ori...

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of sailboat dynamics, specifically to systems and methods for measuring and determining the flying shape and orientation of a sail in relation to the sailboat, utilizing a network of sensors to optimize sail performance.BACKGROUND

[0002] In the field of sailboat dynamics, the accurate measurement and analysis of sail shape and orientation are critical factors that significantly influence the performance of a sailboat. The shape of a sail, commonly referred to as the "flying shape," directly impacts the aerodynamic efficiency of the sail and, consequently, the speed and maneuverability of the sailboat. Sailors and sailing teams often seek to optimize sail shapes to enhance performance, particularly in competitive sailing environments. The term flying shape generally refers to a shape of the sail when the sail is used and captures wind.

[0003] Typically, the measurement of sail shape has been approached through various methods, with one of the most prominent being the use of camera-based systems. These systems utilize cameras mounted at specific locations on the boat to capture images of the sail, which are then processed to determine the sail shape. However, this method presents several challenges. The effectiveness of camera-based systems is highly dependent on environmental conditions, such as light and moisture, which can obscure the lens and distort the data. Also camera-based systems might not be usable for example during night or foggy conditions. Additionally, finding an optimal mounting position for the cameras that provides an unobstructed view of the sail is often difficult, limiting the accuracy of the measurements.

[0004] Therefore, in light of the foregoing discussion, there is a need to overcome the aforementioned limitations to enhance the precision and reliability of sail shape measurement systems. A comprehensive solution is required that can provide accurate real-time data on sail shape and orientation, independent of external environmental conditions, to improve the overall performance of the sailboat.SUMMARY

[0005] The aim of the present disclosure is to provide a system and a method to solve the technical problem of accurately determining a flying shape of a sail on a sailboat, which is important for optimizing sail performance under various sailing conditions. The precise measurement of the sail's shape and orientation directly impacts the aerodynamic efficiency of the sail, influencing the speed and maneuverability of the sailboat. The present disclosure addresses the limitations of existing methods by offering a more reliable and accurate solution.

[0006] The aim of the disclosure is achieved by a system and a method for determining a first flying shape of a sail, comprising a set of sail sensors attached at specific locations on the sail, a reference sensor mounted on the hull of the sailboat, and a processor configured to receive orientation data from each sail sensor and the reference sensor. The processor applies an orientation filter to estimate the orientation of each sail sensor relative to the reference sensor, calculates normal vectors at each respective location on the sail based on the estimated orientation, interpolates these vectors to create a continuous field across the sail's surface, and determines the first flying shape of the sail using the interpolated normal vectors, as defined in the appended independent claims to which reference is made. Advantageous features are set out in the appended dependent claims.

[0007] The embodiments of the present disclosure substantially enable the improvement of sail shape measurement accuracy by minimizing dependency on external factors such as light and moisture conditions, which often compromise the effectiveness of traditional camera-based methods. This system provides more reliable real-time data, allowing sailors to optimize sail performance effectively. Additional aspects, advantages, features, and objects of the present disclosure will be made apparent from the drawings and the detailed description of the illustrative embodiments constructed in conjunction with the appended claims that follow.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the embodiments of the disclosure are shown in the drawings, with references to the following diagrams wherein: FIG. 1A illustrates a system showing the overall configuration; FIG. 1B is a perspective view of the sailboat as seen from a top according to an embodiment; FIG. 1C is perspective view of the sailboat which is leaning to stern side as seen from the aft; FIG. 2A is an illustration horizontal cross section of a first flying shape and a set of sail sensors; FIG. 2B is an illustration of horizontal cross section of a second flying shape and a set of sail sensors; FIG. 3A is an illustration of vertical cross section of a first flying shape and a set of sail sensors; FIG. 3B is an illustration of vertical cross section of a second flying shape and a set of sail sensors and FIG. 4 is an illustration of a system components according to one embodiment. DETAILED DESCRIPTION OF EMBODIMENTS

[0009] The following detailed description illustrates embodiments of the present disclosure and ways in which they can be implemented. The present disclosure provides a system, method, software product, and sail for determining the flying shape of a sail on a sailboat. This system is designed to overcome the limitations of existing methods by providing accurate, real-time data that is independent of environmental conditions such as light and moisture, which typically affect the performance of traditional measurement systems.

[0010] In a first aspect, the present disclosure provides a system for determining a first flying shape of a sail of a sailboat, the system comprising a set of sail sensors, wherein each sail sensor of the set of sail sensors are attached on respective locations on the sail; a reference sensor attached to a hull of the sailboat; a processor configured to: receive orientation data from each sail sensor and the reference sensor; apply an orientation filter to the orientation data to estimate the orientation of each of the sail sensors relative to the reference sensor; calculate normal vectors at each respective location on the sail based on the estimated orientation of each sail sensor; interpolate the normal vectors to create a continuous field of normal vectors across the sail's surface; determine the first flying shape of the sail using the interpolated normal vectors.

[0011] According to one embodiment an orientation filter is applied to sensor data to estimate the orientation of each sail sensor relative to the reference sensor. The orientation filters inputs are readings from a single sail sensor or a reference sensor (lx(acc+mag+gyr)) and the filters output is the orientation of the sensor in Earths reference frame, known as absolute orientation. Each sensor comprises typically three individual sensors. Accelerometer sensor, magnetometer sensor and gyroscope sensor. The said three individual sensors are preferably 3-axis sensors. All of the three individual sensors provide the sensor data.

[0012] The system includes a set of sail sensors strategically attached at specific locations across the sail to capture the orientation data at various points on the sail's surface. As an example, some of the sensors could be placed parallel to battens of the sail. There could be for example 2, 3, 4, 5 or 6 sail sensors in a row (along each of the batten). In general, the set of sail sensors are attached as a grid along sail surface. Number of sensors depend on the size of the sail. Large sail could have several, such as tens of sensors. Distance between the sensors could be arranged as equal distance or the distance can be for example expected curvature of the sail (more expected curvature closer the sensors to each other's). Some of the sensors from the set of sail sensors are preferably arranged close to leech of the sails or at clew of main sail or jib. The respective location information is stored to the system after attaching the sensors. The reference sensor is mounted on the sailboat's hull, providing a fixed point of reference for determining the absolute orientation of the sailboat and the relative orientation of each sail sensor to the sailboat.

[0013] The processor is configured to receive orientation data from each sail sensor and the reference sensor. This orientation data typically includes measurements from accelerometers, gyroscopes, and magnetometers, which are integral components of both the sail sensors and the reference sensor. The processor applies an orientation filter to the received data to estimate the orientation of each sail sensor relative to the reference sensor. In general sampling rate can be arbitrary such as 10, 20, 50, 100Hz or higher depending on need.

[0014] This estimation is crucial as it provides a clear understanding of how each portion of the sail is positioned in relation to the boat and other portions of the sail, directly influencing the aerodynamic properties of the sail.

[0015] To calculate the normal vectors at each respective location on the sail, the processor utilizes the estimated orientation data. A normal vector is a vector perpendicular to the surface at a given point, representing the local orientation of the sail at that location. According to embodiments a normal vector is determined for each sail sensor. Since we know the orientation (and respective location) of each of the sail sensors in respect to the sail (due to attaching those in respective locations) we can collect a set of normal vectors in respect to various points on the sail.

[0016] Following the calculation of the normal vectors, the processor interpolates these vectors to generate a continuous field of normal vectors across the sail's surface. Interpolation, a mathematical technique, is employed to estimate unknown values between known data points. In this system, interpolation creates a smooth and continuous representation of the sail's shape, even at locations where no sensors are directly positioned. This continuous field offers a comprehensive view of the sail's shape, enabling precise analysis and adjustments. Optionally, portions of the sail's flying shape might be determined by extrapolation.

[0017] Purpose of the interpolation process is to smoothly blend the discrete (at respective locations of the sail sensors) normal vectors. This way a normal vector can be calculated at every (needed) point on the surface of the sail by averaging or interpolating the vectors from surrounding points. The resulting continuous normal vector field provides each point on the surface with a well-defined and smoothly varying normal vector, which offers a coherent representation of the surface's orientation.

[0018] As a note, however, in practical calculations, this continuous field is not genuinely continuous but is instead represented by a discretized approximation, where a specific pitch or spacing exists between points. This pitch defines the distance between the points on the surface where normal vectors are calculated or interpolated. While the objective is to approximate a continuous field, the inherent discrete nature of computational methods dictates that the field is sampled only at specific intervals. The accuracy and smoothness of the resulting field are dependent on the density of these points: a finer pitch (smaller spacing) yields a more accurate and smoother approximation of the continuous field, whereas a coarser pitch (larger spacing) may result in noticeable gaps or approximations. This discretization is a necessary compromise in computational methods to balance precision with computational efficiency. For instance, the pitch between the points can be, for example, 1 mm, 5 mm, 1 cm, 10 cm, 30 cm, etc. In some embodiments, the pitch may vary depending on the curvature of the sail surface in the vicinity of the sail sensor.

[0019] Optionally and in addition to interpolating, a part of the flying shape (such as area between a sensor and mast) of the sail could be determined by extrapolating.

[0020] In alternative embodiment a controller of the sail sensors is configured to determine normal in respect to each sail sensor. The normal values can be sent to onboard computer (reference sensors + processor unit) in which then actual flying shape is determined using information from each of the sail sensors. Indeed division of "intelligence" can be arbitrary. In some embodiments the sail sensors can merely provide raw sensor data (such as accelerometer info, magnetometer info and / or gyroscope info) via communication interface to processor. The processor determines from the provided raw sensor data needed orientations, normal vectors and finally the flying shape. In some embodiments the sail sensors can have more intelligence build in those and those could provide, as orientation data, normal of each sensor as an example. In one embodiment some or all of the collected data is processed by processor which is located in cloud.

[0021] The system then determines the first flying shape of the sail using the interpolated normal vectors. The "flying shape" refers to representation of the actual shape that the sail takes when deployed and subjected to wind forces. This shape is critical for understanding how the sail is performing and how it can be adjusted to optimize performance. By using the interpolated normal vectors (of created continuous field of normal vectors), the system can accurately model the entire sail and provide detailed information about its shape.

[0022] Optionally, the sail sensor comprises an accelerometer, a gyroscope, and a magnetometer, and the orientation data comprises measurements from the accelerometer, the gyroscope, and the magnetometer of the sail sensor. These sensors can by understood as "sub sensors" of the sail sensor.). In one embodiment the sail sensor comprises the accelerometer and the magnetometer. These (sub) sensors work together to provide a comprehensive picture of the sail's movement and orientation. The accelerometer measures acceleration forces, which can indicate the motion of the sail , providing data on how the sail is reacting to changes in wind speed and direction . Particularly the accelerometer sensor can be used to determine direction towards earth i.e. towards earth's gravitational field. The gyroscope measures rotational movement, which helps in understanding how the sail is tilting or pivoting, giving insights into the dynamic behavior of the sail. The magnetometer measures the magnetic field, allowing the system to determine the sail's orientation relative to the Earth's magnetic field. The integration of these sensors in the orientation filter provides the absolute orientation which acts as the base for further calculation related to sail shape. The accelerometer sensor is preferably a three axis sensor measuring acceleration in respect to x, y and z directions. The magnetometer sensor can is preferably a three axis sensor measuring direction of magnetic field in respect to x, y and z directions. The gyroscope sensor is preferably a three axis sensor measuring direction of rotations in respect to x, y and z directions. Benefit of 3 axis sensor is that it enables calculation of of absolute orientation (i.e. in respect to Earth for example). Indeed to make the calculation all the sensor should preferably have at least three axes which orientations to each other are known and which aren't on the same plane. Preferably the sensor axes are perpendicular to each others. The sail sensors provide, preferably, the orientation data (sensor data) over wireless interface such as low power Bluetooth to the processor. Alternatively mesh network can be utilized to get data from upper parts of the sail (top of the mast) reliable to the processor.

[0023] This combination of measurements ensures that the system can provide a accurate and reliable estimation of the sail's orientation and shape, even under varying environmental conditions.

[0024] The use of these sensors allows the system to continuously monitor the sail's behavior, providing real-time data that can be used to adjust the sail's shape for optimal performance. For instance, the system can detect when the sail is not performing optimally due to excessive twist or deformation and suggest adjustments to correct this. This capability is particularly valuable in competitive sailing, where small adjustments can make a significant difference in performance.

[0025] In general magnetometer of the sail sensor provides a vector component which is parallel to earth (sea surface). The accelerometer provides a vector component of the sail sensor which is perpendicular to earth (sea surface). These vectors can be used to calculate normal vector for the sail sensor.

[0026] As an example, the accelerometer and magnetometer readings are used to determine the orientation (of each point in which the sail sensor is attached) in a static setting. In practical use case the sails are almost never static, so we also need gyroscope, to compensate in dynamic situations. In practice in dynamic conditions accelerometer is not able to provide direction of the Earth gravitational field as it is disturbed by additional accelerations and movements. Indeed, when sail is for example flapping acceleration caused by the rapid movement can be several times larger than the gravitational attraction (G) of Earth. Gyroscope can be used out to be factor those movements (to a degree) out from the reading and thus normal vectors can be determined more precisely.

[0027] Optionally, the reference sensor comprises an accelerometer, a gyroscope, and a magnetometer, and the orientation data comprises measurements from the accelerometer, the gyroscope, and the magnetometer of the reference sensors.). The reference sensor is mounted on the hull of the sailboat, providing a stable and fixed point of reference against which the orientation of the sail sensors can be compared. This sensor setup ensures that the system can accurately determine the relative orientation of the sail to the boat, which is critical for optimizing the sail's angle of attack and overall aerodynamic efficiency.

[0028] By using a reference sensor that includes an accelerometer, gyroscope, and magnetometer, the system can account for the motion of the boat itself, ensuring that the orientation data from the sail sensors is interpreted correctly.

[0029] Optionally, the processor is further configured to: receive, at a first moment of time, a first set of data from one or more sailboat sensors and associate the received first set of data with the first flying shape. The sailboat sensors might include instruments that measure speed, wind angle, wind speed, and other performance-related metrics. By associating this performance data with the flying shape of the sail, the system can provide a detailed analysis of how different sail shapes affect the sailboat's performance.

[0030] This functionality enables the system to track how specific sail shapes correlate with the boat's speed, stability, and maneuverability under various weather conditions . For example, the system could identify that a particular sail shape consistently results in higher speeds when sailing close to the wind. Sailors can then adjust their sails to replicate this shape in similar conditions, thereby enhancing performance. Additionally, this data can be stored and reviewed after sailing sessions to help teams refine their sail configurations and strategies for future races.

[0031] Optionally, the processor is further configured to: receive, at a second moment of time, a second set of data from the one or more sailboat sensors, wherein the second moment of time is after the first moment of time; determine a second flying shape associated with the second moment of time; compare the first set of data and the second set of data and if based on the comparison boat performance indicator was higher at the first movement of time than at the second moment of time indicate with a user interface corrective actions related to the second flying shape. This capability allows the system to continuously monitor and compare the effectiveness of different sail shapes over time.

[0032] According to an embodiment, the determined flying shape (the first flying shape and / or the second flying shape) can be used to provide a set of data to at least one of: autopilot controlling a direction of the sailing boat, actuators of the sail, user interface of on-board computer. As an example, the set of data can be used to provide data related to steering of the boat as well as trimming of the sails. The set data can be used for rendering for a user (sailor or grew) the flying shape of the sail or it can be used to control for example autopilot of the sailing boat or for example automatically adjust sails. As an example, if the second flying shape could be corrected to same as the first flying shape by releasing mainsheet or sheet of the jib using actuator related to the sail. The set of data can be used also to indicate (over user interface) this to sailor or to automatic system.

[0033] By comparing performance data at different times, the system can identify when a change in the sail's shape has negatively impacted the boat's performance. For instance, if the boat's speed drops after the sail is adjusted, the system can analyze the shape and suggest corrective actions to restore optimal performance. This feature is particularly useful in real-time sailing situations, where conditions can change rapidly, and quick adjustments are necessary to maintain peak performance. As an example wind speed at the first moment of time was 5m / sec and true angle of the wind was 40 degrees. Speed of the boat towards wind was 4knots. A first flying shape is determined at said first moment of time. At the second moment of time (such as few minutes later or next day or next time sailing) wind speed and true angle are same. Theoretically now if the second flying shape is identical to the first flying shape the boat should travel towards wind with same 4knots. If as an example speed is 3knots this can be indicated to sailor. One way to indicate this is to show next to each others or as overlay images the first flying shape and the second flying shape and high light the differences. This way the sailor gets feedback on the second flying shape and can do adjustments to get it to same or similar as the first flying shape thus increasing the speed from 3knots to 4 knots.

[0034] Optionally, the boat performance indicator is based on at least one of: speed of the boat, close-haul angle of the boat, running speed, velocity made good to target, velocity made good to windward, wind adjusted speed of the boat. These performance indicators provide outline to assets the sailboat's effectiveness under different sailing conditions. In this regards the term "higher" in respect to the comparing boat performance indicator refers to any measurable parameter. As an example, performance is higher if the speed is higher. Another example performance is higher if close-haul angle is smaller.

[0035] For example, the "velocity made good to windward" is a critical metric in competitive sailing, as it measures how efficiently a boat is moving towards the wind, which is important during upwind legs of a race. By analyzing how the sail's shape affects these indicators, the system helps sailors fine-tune their sails to maximize efficiency and speed. This detailed performance analysis is invaluable for competitive sailors who need to optimize every aspect of their sailboat's setup.

[0036] Optionally, the set of sail sensors are attached to the sail by at least one: double sided tape, sewing pockets, attached to a batten of the sail, Velcro straps, and / or embedded in the sail. The method of attaching the sensors to the sail is crucial for ensuring that they remain securely in place while also minimizing any impact on the sail's aerodynamic properties.

[0037] Different attachment methods provide flexibility depending on the type of sail and the specific sailing conditions. For instance, embedding the sensors in the sail or attaching them to battens might be preferable for high-performance racing sails, where minimal drag and a streamlined profile are critical. In contrast, using Velcro straps or sewing pockets might be more suitable for sails used in less demanding conditions, where ease of attachment and removal are more important. The choice of attachment method also ensures that the sensors can be positioned precisely where needed to capture the most relevant data.

[0038] Optionally, the system comprises a boom orientation sensor to measure the orientation of the boom in respect to the hull and at least one of the sail sensors to determine the twist of a mainsail in respect to the boom. The twist of the sail refers to the difference in angle between the top and bottom of the sail, which affects how the sail interacts with the wind.

[0039] Measuring and controlling sail twist is critical for optimizing sail shape, particularly in varying wind conditions. Too much twist can lead to a loss of power, while too little can cause the sail to stall. By using a boom orientation sensor in conjunction with the sail sensors, the system can provide precise data on the twist of the sail, allowing sailors to make fine-tuned adjustments to achieve the ideal sail shape. This capability is especially important in races where wind conditions change frequently, and maintaining the optimal sail shape can be the difference between winning and losing.

[0040] In a second aspect, the present disclosure provides a method for determining a first flying shape of a sail of a sailboat, the method comprising receiving orientation data from sail sensors attached on respective locations on the sail and from a reference sensor attached on a hull of the sailing boat; applying an orientation filter to the orientation data to estimate the orientation of each of the sail sensors relative to the reference sensor; calculating normal vectors at each respective location on the sail based on the estimated orientation of each sail sensor; interpolating the normal vectors to create a continuous field of normal vectors across the sail's surface; determining the first flying shape of the sail using the interpolated normal vectors. In one embodiment the orientation filter employed in this method is particularly optimized for low-power and real-time applications. It achieves high accuracy in orientation estimation even with minimal computational resources, making it ideal for use in onboard sailing systems. One example of filter can be a quaternion filter representation ensures that the calculations remain robust and free from the limitations of traditional orientation estimation methods.

[0041] This method provides a structured process for accurately determining the sail's shape and orientation, enabling real-time adjustments and performance optimization.

[0042] This method ensures that critical data points across the sail's surface are captured and analyzed, allowing for the accurate reconstruction of the sail's flying shape. By applying this method, sailors can continuously monitor and adjust the sail's shape to maintain optimal performance, even in changing wind conditions. The ability to interpolate normal vectors ensures that even areas of the sail that are not directly monitored by sensors are sufficiently represented in the overall shape analysis. It has been found out surprisingly that even a small number of sensors (say 3-5 per row and number of rows such as row per 1-5 meter of the sails vertical height) provide information for sailor which outperforms prior art ways of determining the flying shape.

[0043] Optionally, the method further comprises collecting boat sensor data to determine a boat performance indicator for a first moment of time and associating the respective first flying shape of the sail to the determined boat performance indicator. This step allows the method to link specific sail shapes to measurable performance outcomes, providing valuable feedback for sailors looking to optimize their sail configurations.

[0044] By associating the sail shape with performance indicators, sailors can better understand the impact of their adjustments and make data-driven decisions on how to set their sails for different conditions. This method not only enhances real-time decision-making but also provides valuable insights for post-race analysis, helping teams to refine their strategies and sail configurations for future competitions.

[0045] Optionally, the method further comprises collecting boat sensor data to determine a boat performance indicator for a second moment of time, which the second moment of time is after a first moment of time; determining a second flying shape associated with the second moment of time; comparing the boat performance indicator of the first moment of time with the boat performance of the second moment; if based on the comparison boat performance indicator was higher at the first movement of time than at the second moment of time indicate with a user interface corrective actions related to the second flying shape. This process helps sailors continuously improve their sail configurations by providing real-time feedback and suggestions based on past performance.

[0046] The ability to compare performance over time is important for understanding how changes in sail shape affect overall sailing efficiency. This method provides a systematic approach to evaluating sail adjustments, allowing for continuous improvement. The feedback provided by the system can be used to make immediate corrections during a race or to inform future adjustments in similar conditions.

[0047] In a third aspect, the present disclosure provides a software product for execution on a computer system, wherein the software product is configured to execute the above discussed method. This software product facilitates the implementation of the method by providing the necessary algorithms and user interface for processing the data, calculating the sail's shape, and offering performance feedback.

[0048] The software product is designed to be used on various computing devices, from onboard computers to tablets or smartphones, allowing for flexible deployment in different sailing environments. The user interface is intuitive, providing clear visualizations of the sail's shape and performance metrics, making it easier for sailors to interpret the data and make informed decisions. The software also supports data storage and analysis, enabling teams to review and learn from past performances.

[0049] In a fourth aspect, the present disclosure provides a sail, comprising a set of sail sensors attached to the sail at determined locations. This sail is designed to integrate seamlessly with the system, providing accurate and reliable data on the sail's shape and orientation.

[0050] The integration of sensors directly into the sail fabric ensures that the data collected is precise and relevant, reflecting the actual conditions experienced by the sail. This integration is particularly important for high-performance racing sails, where even small inaccuracies in shape can lead to significant performance losses. By incorporating the sensors into the sail, the system ensures that all data is directly related to the sail's performance, providing the most accurate possible analysis.

[0051] Optionally, each sail sensor of the set of sail sensors comprises, a sub sensor such as: an accelerometer, a gyroscope and / or a magnetometer, and a communication interface to provide data from the accelerometer, the gyroscope and the magnetometer to a computer system. These sensors work together to provide comprehensive data on the sail's movement and orientation, which is then processed by the system to determine the sail's flying shape.

[0052] The communication interface ensures that data from the sail sensors is transmitted reliably and efficiently to the central processor, allowing for real-time analysis and adjustments. This setup is critical for competitive sailing, where decisions need to be made quickly based on the most current data. The combination of these sensors provides a full picture of the sail's behavior, from its overall shape to its response to dynamic forces like wind and boat movement.

[0053] The present disclosure, through its various aspects, provides a detailed and robust solution for determining and optimizing the flying shape of sails on sailboats. By leveraging advanced sensor technology and sophisticated data processing methods, this system enables sailors to achieve better performance and efficiency in a wide range of sailing conditions.DETAILED DESCRIPTION OF THE DRAWINGS

[0054] Referring to FIG. 1A, illustrated is an embodiment of a system designed to determine the first flying shape 152A, 150B of sails 150A (main sail) and 150B (jib) of a sailboat 140. The sailboat 140 is equipped with multiple sensors, including sail sensors 110, 110A, 110B which are attached to various respective locations on the sails 150A, 150B. Additionally, sailboat sensors 120, 122, 124 are positioned on different parts of the sailboat 140 to collect data regarding the boat's orientation and movement. In figure sailboat sensor 120 is log for measuring speed of the boat, sensor 122 is wind direction and speed sensor, sensor 124 is a global positioning sensor. A boom orientation sensor 130 is attached to the boom to measure its orientation in relation to the hull 142 and at least one of the sail sensors 110B to determine the twist of a main sail 150A in respect to the boom.

[0055] The system comprises a reference sensor 112 mounted on the hull 142 of the sailboat 140. This reference sensor 112 provides a stable reference point for the orientation data collected by the sail sensors 110 110A. The processor 114, which is part of the onboard computer 116, receives and processes the orientation data to calculate the normal vectors at various points on the sails. The processor 114 of the onboard computer 116 uses these normal vectors to determine the first flying shape 152A of the sail 150A, optimizing the sail's configuration for better performance. As an example, the onboard computer can be dedicated "flying shape" determining computer which houses the processor 114 dedicated for flying shape calculations as well as the reference sensors. Alternatively, the onboard computer can be calculation unit for other tasks as well. In one embodiment the onboard computer could be a navigation computer. The sail sensors provide, in given example, the orientation data to the processor wirelessly.

[0056] Referring to FIG. 1B, the figure illustrates the system in perspective (cross section A-A of the figure 1A), focusing on the relationships and structural configuration of the sensors and components involved. The sail sensors 110, 110A, are attached to the sails. As an example of sailboat sensor, a sailboat sensor (GPS) 124 is attached to the sailboats deck. The reference sensor 112 is securely mounted on the hull 142 inside the onboard computer 116, providing a consistent reference for the data collected by the sail sensors. In some embodiments the GPS sensor can be part of the onboard computer 116.

[0057] The boom orientation sensor 130 is illustrated in its position relative to the sailboat's hull 142 and at least one of the sail sensors to determine the twist of a main sail in respect to the boom, highlighting its role in measuring the boom's orientation for determining twist of the sail. The onboard computer 116, which includes the processor 114, is responsible for processing the data from the sensors to determine the flying shape of the sail. This configuration ensures that the system can accurately monitor and adjust the sails for optimal performance. In the figure true wind angle (TWA) and apparent wind angle (AWA) are presented in respect to direction of the sailing boat 142. Also orientation (direction) of the sailing boat in respect to north (N) is illustrated.

[0058] Referring to FIG. 1C, illustrated is a view of the system in a perspective view (cross section B-B of the figure 1B), focusing on the structural and functional relationships between the mast 160, the onboard computer 116, and the sensors. The sail sensor 110 is shown in its attached positions on the sails, with the mast 160 providing the structural support necessary for the sails to function effectively. The hull 142 is depicted as the foundation where the reference sensor is mounted, providing the stable point of reference needed for accurate orientation data. The onboard computer 116, which processes the data from the sail sensors and the reference sensor, calculates the normal vectors and interpolates these to determine the first flying shape of the sail. This perspective view highlights the integration of the mast 160 and the onboard computer 116 into the overall system, demonstrating how the components work together to optimize sail performance. As an example accelerator sensor reading of the reference sensor in given example figure can be used to determine how many degrees the boat tilts due to wind.

[0059] Referring to FIG. 2A, illustrated is the sensors attached to the sail, where a different set of sail sensors 210 is used to determine the first flying shape 252A of a sail. The sail sensors 210 are positioned at different locations on the sail, and they work with the processor to calculate the normal vectors and interpolate them to create a continuous field across the sail's surface. The normal vector 270, derived from the orientation data provided by the sail sensors 210, is used to determine the first flying shape 252A. This figure illustrates the flexibility of the system in accommodating various sensor configurations while maintaining accurate measurements and optimal sail performance.

[0060] Referring to FIG. 2B, illustrated is the sensors attached to the sail in which a reference sensor 212 is attached to the hull, similar to the setup shown in previous figures. The reference sensor 212 provides a stable reference point for the system to compare the orientation data from the sail sensors. The processor uses this data to determine the second flying shape 252B of the sail. This figure underscores the importance of having a reliable reference sensor 212 to ensure the accuracy of the system's calculations. The relationship between the sail sensors and the reference sensor 212 is crucial for optimizing the sail's performance by adjusting its flying shape in real time.

[0061] In figures 2A and 2B is illustrated sensor reading from magnetometer of the sail sensor. Indeed, the magnetometer reading can provide a vector component which is parallel to sea surface. The reference sensors (magnetic reading) can be used to calibrate this.

[0062] Referring to FIG. 3A and 3B, illustrated is an embodiment of the system, where sail sensors 310 are attached to the sail at different locations in respect to vertical direction of the mast. A reference sensor 312 is mounted on the hull to provide a reference for the orientation data collected by the sail sensors 310. The processor, in conjunction with the onboard computer, calculates the normal vectors based on this data to determine the first flying shape 352A and a second flying shape 352B of the sail. A direction of the normal vector 370 is indicated in figures. The FIG 3A is an illustration of situation in which the sailing boat is not tilting. In FIG 3B the sailing boat is tiling angle a due to wind. It can be seen that first flying shape is different from the second flying shape in the presented example. Refence sensor reading is used to detect tiling. This information is used by orientation filter to estimate the orientations of each sail sensors.

[0063] In figures 3A and 3B is illustrated sensor reading from accelerometer sensor of the sail sensor. Indeed the accelerometer readings can provide a vector component which is perpendicular to the sea surface. The reference sensors (accelerator reading) can be used to calibrate this.

[0064] Together the vector component associated with magnetic sensor and the vector component associated with the accelerometer sensor can be used to determine normal vector for each of the sail sensors.

[0065] The sail sensor also comprise gyroscope. Role of the gyroscope is to provide filtering information to make reading of normal more accurate. As an example, if gyroscope shows lots of movements at given moment of time this can be taken in consideration when selecting datapoints for flying sail shape determination.

[0066] Referring to FIG. 4, illustrated is the system 400, showcasing the components and their interactions. The system comprises a sails sensor 410, which houses the accelerometer 4102, magnetometer 4104, gyroscope 4106, and communication interface 4100. The accelerometer, magnetometer and gyroscope are preferably 3-axis sensors. The sail sensor 410 comprises also a power source. As an example communication interface 4100 can be Bluetooth interface for sending data from the sensors to other parts of the system. In alternative / additional embodiment the sail sensor 410 can include also a processor / controller for determining locally the orientation (direction of normal) for the sail sensor. These sail sensors collect detailed orientation data. The data is provided via the communication interface 4100 to the onboard computer 416 via communication interface 4120 of the onboard computer 416. The data is processed by the processor 4128 of the onboard computer 416. The onboard computer 416 comprises reference sensor 412. The reference sensor 412 comprises accelerometer 4122, gyroscope 4124, and magnetometer 4126, to provide the necessary reference point for the system. The accelerometer, magnetometer and gyroscope are preferably 3-axis sensors. The onboard computer 412 processes the data from these sensors to determine the first flying shape of the sail. The onboard computer 412 can be connected to a boat network482 that connects all the components. The system can be used via a user interface 480. The user interface can be used to provide feedback to the sailor and grew. In one example embodiment the user interface 480 is onboard navigation equipment, in one example the user interface 480 can be part of the onboard computer. In one example the user interface 480 can be implemented in smart phone or tablet computer. Wireless communication modules 4100, 4120 ensure that data is seamlessly transmitted between the sensors and the onboard computer (thus the processor). The system also includes sailboat sensors 420, 422, 424, which are positioned on various parts of the sailboat to monitor additional parameters like boat speed, angle, and environmental conditions. These sensors provide data that can be used for the overall performance assessment of the sailboat. A boat network 482 connects all these components, facilitating seamless communication across the system. Example of the boat network in National Maritime Electronics Association (NMEA) based network. The user interface 480 provides real-time feedback to the operator, enabling them to make informed adjustments. Wireless communication modules 4100, 4120 ensure the smooth transmission of data between the sensors and the onboard computer. In one example embodiment the processor (thus the onboard computer) can send via the boat network commands to various actuators of the boat such as autopilot depending on determined flying shape of the sail.

Examples

Embodiment Construction

[0009]The following detailed description illustrates embodiments of the present disclosure and ways in which they can be implemented. The present disclosure provides a system, method, software product, and sail for determining the flying shape of a sail on a sailboat. This system is designed to overcome the limitations of existing methods by providing accurate, real-time data that is independent of environmental conditions such as light and moisture, which typically affect the performance of traditional measurement systems.

[0010]In a first aspect, the present disclosure provides a system for determining a first flying shape of a sail of a sailboat, the system comprising a set of sail sensors, wherein each sail sensor of the set of sail sensors are attached on respective locations on the sail; a reference sensor attached to a hull of the sailboat; a processor configured to: receive orientation data from each sail sensor and the reference sensor; apply an orientation filter to the ori...

Claims

1. A system (400) for determining a first flying shape (152A, 252A, 352A, 150B) of a sail (150A, 150B) of a sailboat (140), the system comprising a set of sail sensors, wherein each sail sensor (110, 110A, 110B, 210, 310) of the set of sail sensors are attached on respective locations on the sail; a reference sensor (112, 212, 312, 412) attached to a hull (142) of the sailboat; a processor (114, 4128) configured to: receive orientation data from each sail sensor and the reference sensor; apply an orientation filter to the orientation data to estimate the orientation of each of the sail sensors relative to the reference sensor; calculate normal vectors at each respective location on the sail based on the estimated orientation of each sail sensor; interpolate the normal vectors to create a continuous field of normal vectors across the sail's surface; determine the first flying shape of the sail using the interpolated normal vectors.

2. A system according to claim 1, wherein the sail sensor comprises an accelerometer (4102), a gyroscope (4104), and a magnetometer (4102) and the orientation data comprises measurements from the accelerometer, the gyroscope, and the magnetometer of the sail sensor.

3. A system according to any of the preceding claims, wherein the reference sensor comprises an accelerometer (4122), a gyroscope (4124), and a magnetometer (4126) and the orientation data comprises measurements from the accelerometer, the gyroscope, and the magnetometer of the reference sensors.

4. A system according to any of the preceding claims, wherein the processor is further configured to: receive, at a first moment of time, a first set of data from one or more sailboat sensors (120, 122, 124, 420, 422, 424) and associate the received first set of data with the first flying shape.

5. A system according to claim 4, wherein the processor is further configured to: receive, at a second moment of time, a second set of data from the one or more sailboat sensors, wherein the second moment of time is after the first moment of time; determine a second flying shape (352B, 252B) associated with the second moment of time; compare the first set of data and the second set of data and if based on the comparison boat performance indicator was higher at the first movement of time than at the second moment of time indicate with an user interface corrective actions related to the second flying shape.

6. A system according to claim 5, wherein the boat performance indicator is based on at least one of: speed of the boat, close-haul angle of the boat, running speed, velocity made good to target, velocity made good to windward, wind adjusted speed of the boat.

7. A system according to any of the preceding claims wherein the set of sail sensors are attached to the sail by at least one: double sided tape, sewing pockets, attached to a batten of the sail, Velcro straps, and / or embedded in the sail.

8. A system according to any of the preceding claims, wherein the system comprises a boom orientation sensor (130) to measure orientation of the boom in respect to the hull and at least one of the sail sensors to determine twist of a main sail in respect to the boom.

9. A system according to any of the preceding claims, wherein the determined flying shape is used to provide a set of data to at least one of: autopilot controlling a direction of the sailing boat, actuators of the sail, user interface of on-board computer.

10. A method for determining a first flying shape of a sail of a sailboat, the method comprising receiving orientation data from sail sensors attached on respective locations on the sail and from a reference sensor attached on a hull of the sailing boat; applying an orientation filter to the orientation data to estimate the orientation of each of the sail sensors relative to the reference sensor; calculating normal vectors at each respective location on the sail based on the estimated orientation of each sail sensor; interpolating the normal vectors to create a continuous field of normal vectors across the sail's surface; determining the first flying shape of the sail using the interpolated normal vectors.

11. A method according to claim 10 wherein the method further comprises collecting boat sensor data to determine boat performance indicator for a first moment of time and associating respective the first flying shape of the sail to the determined boat performance indicator.

12. A method according to claim 11, wherein the method further comprises collecting boat sensor data to determine boat performance indicator for a second moment of time, which the second moment of time is after a first moment of time; determining a second flying shape associated with the second moment of time; comparing the boat performance indicator of the first movement of time with the boat performance of the second movement; if based on the comparison boat performance indicator was higher at the first movement of time than at the second moment of time indicate with an user interface corrective actions related to the second flying shape.

13. A software product for execution on a computer system, wherein the software product is configured to execute method of any of the claims 10 to 12.

14. A sail, comprising a set of sail sensors attached to the sail at determined locations.

15. A sail according to claim 14, wherein each sail sensor of the set of sail sensors comprise an accelerometer, a gyroscope and a magnetometer, and a communication interface to provide data from the accelerometer, the gyroscope and the magnetometer to a computer system.

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