Device and method for determining an orientation of a kite in flight

Abstract

The invention relates to a method for determining an orientation of a kite (3) in flight, the kite being retained by at least a first line (41) and a second line (42), the determination method comprising: - a step of determining a relative position of the first and second lines in a frame of reference (R), in particular in a geocentric frame of reference or in a frame of reference of a system (2), and - a step of determining orientation values for the kite (3) using the relative position of the first and second lines, the orientation values of the kite including a yaw angle value of the kite for a wing (31) of the kite.

Description

[0001] DESCRIPTION

[0002] TITLE: Device and method for determining the orientation of a kite in flight.

[0003] Technical field of the invention

[0004] The invention relates to kites used:

[0005] - for towing a floating vessel,

[0006] - for traction of a rolling and / or sliding land vehicle,

[0007] - for the production of electrical energy by converting mechanical energy,

[0008] - in pumping applications using mechanical energy produced by the kite, or

[0009] - in desalination applications using mechanical energy produced by the kite.

[0010] The invention relates more specifically to a method for determining the orientation of a kite in flight. The invention also relates to a device for determining this orientation that implements such a method. The invention further relates to a computer program comprising code instructions for implementing such a method. The invention also relates to a data storage medium for implementing such a method. Finally, the invention relates to a signal from a data storage medium carrying such a computer program.

[0011] Prior art

[0012] Kites are known for traction on a floating vessel, such as a boat or ship. The kite can be flown in different ways, notably in a figure-eight pattern and a stationary or relatively fixed position relative to its attachment point. Kites designed to convert mechanical energy into electricity may exhibit similar flight modes.

[0013] To create and maintain such flight conditions, one acts by applying forces and moving lines connecting a structure of a system (engine, boat, ship, energy converter) to the kite. To apply the correct force at the right time to a line, it is useful to know, in real time, one or more of the following pieces of information:

[0014] - the position of the kite (for example, azimuth and elevation angles), and / or

[0015] - the orientation of the kite (yaw angle or leading edge angle),

[0016] - the incidence of the kite,

[0017] - the speeds of the kite,

[0018] - the wind direction, and

[0019] - the force of the wind.

[0020] To obtain such information, it is common practice to attach an inertial measurement unit (IMU) to the kite wing or at the wing level. However, this solution has drawbacks. The IMU must have its own power source (such as a battery and / or solar panel) to operate and transmit data. This makes the solution complex and cumbersome. Furthermore, attaching an IMU to the wing or at the wing level disrupts the fluid flow around the wing and negatively impacts its aerodynamic performance. Additionally, this solution requires radio communication from the IMU, and this communication can be disrupted in certain kite configurations and / or difficult to secure. Moreover, calibrating such an IMU is complicated. Finally, the IMU vibrates at the wing level.It follows that the information collected by the inertial measurement unit is very noisy.

[0021] Presentation of the invention

[0022] The invention relates to a device and method for determining the orientation of a kite in flight, improving upon known devices and methods. In particular, the invention provides a simple, robust device and method for determining the orientation of a kite in flight, enabling reliable and precise information on the kite's orientation without disturbing the wing's aerodynamics.

[0023] Summary of the invention

[0024] According to a first aspect of the invention, a determination method is defined by claim 1.

[0025] According to a second aspect of the invention, a determination method is defined by claim 4.

[0026] Different modes of execution of the processes are defined by claims 2 to 3 and 5 to 11.

[0027] A determination device according to the invention is defined by claim 12.

[0028] An arrangement according to the invention is defined by claim 13.

[0029] A programmed product according to the invention is defined by claim 14.

[0030] A recording medium according to the invention is defined by claim 15. A signal from a data medium according to the invention is defined by claim 16.

[0031] According to another aspect of the invention, the method allows the orientation of a kite to be determined in flight, the kite being held by at least a first line and a second line, the determination method comprising:

[0032] - a step of determining the relative position of the first and second lines in a reference frame, in particular in a geocentric reference frame or in the reference frame of a device towed by the kite, and

[0033] - a step of determining kite orientation values ​​using the relative position of the first and second lines, the kite orientation values ​​including a kite yaw angle value of one wing of the kite.

[0034] The process may include a step of determining kite position values ​​using the relative position of the first and second lines, the kite position values ​​including:

[0035] - an azimuth angle value of the kite wing, and / or

[0036] - a value for the elevation angle of the kite's wing.

[0037] The step of determining a relative position of the first and second lines in a reference frame may include a step of determining a relative position of a first point of the first line relative to a second point of the second line in the reference frame.

[0038] The first point can be maintained at a constant distance from the second point, or the first and second points can be movable relative to each other in a plane at least substantially perpendicular to the first and second lines. The first point can be a fixed point or a movable point on the first line, and / or the second point can be a fixed point or a movable point on the second line.

[0039] The step of determining a relative position of the first and second lines in a reference frame can be carried out by a measurement element linking the first point and the second point.

[0040] The measuring element may include a means of measuring the orientation of the measuring element in a geocentric reference frame, in particular an accelerometer, especially a 3-axis accelerometer, and possibly a magnetometer.

[0041] The measuring element may include a means for measuring the orientation of the measuring element, in particular a sensor for measuring an angle of rotation around the direction of pull of the kite, of rotation.

[0042] According to another aspect of the invention, a device for determining the orientation of a kite in flight comprises hardware and / or software elements implementing the method defined above, in particular hardware and / or software elements designed to implement the method defined above.

[0043] According to another aspect of the invention, a device for determining the orientation of a kite in flight includes means for implementing a method defined previously.

[0044] According to another aspect of the invention, an arrangement comprises:

[0045] - a system,

[0046] - a kite, - a tethering device, and

[0047] - a determination device defined previously.

[0048] According to another aspect of the invention, a computer program product comprises program code instructions recorded on a computer-readable medium to implement a previously defined process when said program is running on a computer.

[0049] According to another aspect of the invention, a computer program product downloadable from a communication network and / or recorded on a data medium readable by a computer and / or executable by a computer, includes instructions which, when the program is executed by the computer, lead the latter to implement a previously defined process.

[0050] According to another aspect of the invention, a computer-readable data storage medium on which a computer program is recorded includes program code instructions for implementing a previously defined method.

[0051] According to another aspect of the invention, a computer-readable recording medium comprising instructions which, when executed by a computer, cause the computer to implement a previously defined process.

[0052] According to another aspect of the invention, a signal from a data carrier carries the product computer program defined previously.

[0053] Presentation of the figures

[0054] Other advantages and features will become clearer from the following description of an embodiment of a device for determining the orientation of a kite in flight and the accompanying figures in which:

[0055] Figure 1 is a schematic view of an arrangement according to a first embodiment.

[0056] Figure 2 is a partial schematic view of an arrangement according to a second embodiment.

[0057] Figure 3 is a partial schematic view of an arrangement according to a third embodiment.

[0058] Detailed description

[0059] A first embodiment of an arrangement 200 according to the invention is described below with reference to figure 1.

[0060] The 200 layout includes:

[0061] - a system 2,

[0062] - a kite 3,

[0063] - a lashing device 1, and

[0064] - a device 100 for determining the orientation of a kite in flight.

[0065] Kite 3 includes:

[0066] - a wing 31,

[0067] - a first line 41, and

[0068] - a second line 42.

[0069] Advantageously:

[0070] - the first line 41 is fixed to a first lateral end of the wing 31 or in the vicinity of the first lateral end of the wing 31, and

[0071] - The second line 42 is attached to a second lateral end of the wing 31 or in the vicinity of the second lateral end of the wing 31, the second lateral end being opposite the first lateral end. The first and second lines allow the wing 31 to be mechanically linked to the structure of system 2, via the lashing device 1.

[0072] The arrangement may also include a control device (not shown) comprising:

[0073] - one or more line control actuators, and

[0074] - means of controlling this or these actuators.

[0075] System 2 can include, in particular:

[0076] - a floating vessel, such as a boat or ship, or

[0077] - a rolling and / or sliding land vehicle, or

[0078] - an energy converter, in particular a mechanical energy converter into electrical energy, i.e. an alternator, or

[0079] - a pumping installation, or

[0080] - a water desalination plant.

[0081] Kite 3 can be of different technologies. For example, kite 3 may consist of only two lines, 41 and 42, as shown in Figures 1 and 2. Alternatively, kite 3 may include:

[0082] - two lines before 41, 42 and

[0083] - two back lines.

[0084] Each line is preferably made up of a rope. Each line is:

[0085] - attached to wing 31 at a distal end of the line, and

[0086] - fixed or linked to the lashing device 1 at a proximal end 45, 46 of the line.

[0087] The proximal ends 45 and 46 can serve as points of contact between the lines 41 and 42 and a pulley of the tethering device. For example, in the case of a four-line kite, a greater or lesser extension of the front lines 41 (relative to the rear lines) allows for a greater or lesser angle of attack of the wing 31 in the airflow through which it moves. Consequently, the wing's lift and speed can be defined or adjusted.

[0088] For example, in the case of a four-line kite, a greater or lesser relative difference in the length of the rear lines 42 allows the wing 31 to be oriented and to involve variations in the trajectory of the wing, that is to say to cause turns of the wing 31 (rotation around the yaw axis Z in the orthonormal frame X, Y, Z linked to the wing).

[0089] An axis A is generally or substantially parallel to lines 41 and 42, which connect wing 31 to the structure of system 2 via the lashing device 1. This axis A is defined by the mechanical tensile forces exerted by the lines. This direction can be identified by:

[0090] - an azimuth angle α, and

[0091] - an angle of elevation [3, relative to the structure of system 2.

[0092] The 100 device for determining the orientation of a kite in flight includes:

[0093] - a measuring element 5 connecting a first point 43 of the first line 41 to a second point 44 of the second line 42, and

[0094] - a logical processing unit 6 intended to process the information provided by the measuring element 5 and to use it to determine an orientation of the kite 3.

[0095] The logic processing unit 6 can also process the information provided by the measuring element 5 and use it to determine the position of the kite 3, such as its azimuth and / or elevation. By "logic processing unit," we preferably mean all the hardware and / or software means that enable the kite control actions, in particular motor control commands, to be determined from raw data from elementary sensors (such as an accelerometer or a magnetometer 54) included in the measuring element. A first part of these means may include elements capable of determining the complete orientation of the measuring element 5, that is, for example, determining the orientation angles of the measuring element 5 relative to the geocentric reference frame.A second part of these means may include elements capable of determining the control actions based on the complete orientation of the measuring element 5, that is, of determining the control commands for the motors driving the kite. The first part of the means may be contained in a first housing and the second part of the means may be contained in a second housing, the first and second housings being physically separate.

[0096] The measuring element 5 includes, for example, a rigidly fixed frame 55:

[0097] - on the one hand, in the first line 41, in the first point 43, and

[0098] - on the other hand, in the second line 42 in the second point 44.

[0099] These two points define an orientation of the measurement element, this orientation being characterized by a straight line B passing through the first and second points.

[0100] The chassis 55 incorporates a means 51 for measuring the orientation of the measuring element 5. The measuring element 5 may thus comprise:

[0101] - a chassis 55, and

[0102] - a means 51 for measuring the orientation of the measuring element 5, the measuring means 51 being fixed to the frame 55. For example, the measuring means 51 is an inertial measurement unit or a three-axis accelerometer. The measuring means 51 makes it possible to determine the direction of the line B in a geocentric reference frame R. The information is, for example, transmitted wirelessly via an antenna 53. Alternatively, the measuring element 5 can be powered and can communicate wirelessly. Powering and communication can be easily accomplished wirelessly, since the measuring element 5 is, for example, fixed less than 5 m, in particular less than 2 m, from the structure of the system 2.

[0103] The direction of line B and the distance separating the first and second points constitute information about the relative position of the first and second lines.

[0104] Furthermore, the tethering device 1 may optionally include a directional force sensor 1 to determine the direction of the kite's traction line A. To do this, the movements of system 2 may need to be taken into account. In this case, the directional sensor determines a direction relative to a frame of reference of system 2. In the case of a vessel 2, system 2 can move (roll and / or pitch) relative to a geocentric frame of reference. The direction we seek to determine is indeed that relative to the geocentric frame of reference.

[0105] Finally, the control system knows the difference in length between the first and second lines.

[0106] All this information (direction of line B, direction of line A, difference in length between the first and second lines) is sent to the logic processing unit 6, which determines the complete orientation of line B and the orientation of the kite's leading edge. This information also allows the yaw angle (or leading edge orientation angle) of the wing to be determined, and in particular its variations over time.

[0107] However, preferably, the yaw angle (or leading edge angle) of the wing is directly determined by processing only the information provided by measurement element 5. Even more preferably, the azimuth and elevation angles are also directly determined by processing only the information provided by measurement element 5. Preferably, by way of example, the fact that:

[0108] - the leading edge of the wing and line B are parallel or substantially parallel, or

[0109] - the leading edge of the wing and line B are in the same plane or substantially in the same plane.

[0110] The logic processing unit comprises a microprocessor 61, a memory 62, and optionally an antenna 63 to receive various data and send relevant information, such as the leading edge orientation of the kite's wing 31, to the control device. As previously mentioned, information can alternatively be transmitted via wires between the different components.

[0111] A second embodiment of an arrangement 200 according to the invention is described below with reference to figure 2.

[0112] The 200 layout includes:

[0113] - a system 2,

[0114] - a kite 3,

[0115] - a lashing device 1, and

[0116] - a device 100 for determining the orientation and, possibly, the position of a kite in flight. Kite 3 comprises:

[0117] - a wing 31,

[0118] - a first line 41, and

[0119] - a second line 42.

[0120] Preferably, the second embodiment differs from the first embodiment only in that the lashing device comprises:

[0121] - a mechanical linkage 8 allowing for a ball joint, which is for example achieved by two pivot joints mounted in series and having non-parallel axes, and

[0122] - a pivot joint 7 guiding in rotation, around the axis A, a guide element 59 of the first and second lines 41, 42.

[0123] Consequently, measurement element 5 is different. It includes:

[0124] - the guide element 59, which is for example a plate with two holes 57, 58 for guiding or passing the first and second lines 43, 44, and

[0125] - a sensor 52 which allows to determine or measure the angular position of the guide element 59 around the axis A.

[0126] In this second embodiment, the device 100 for determining the orientation of the kite in flight also includes a measuring element 5 connecting a first point 43 of the first line 41 to a second point 44 of the second line 42. However, here, the first point 43 is movable relative to the first line 41 and the second point 44 is movable relative to the second line 42. Indeed, the lines can slide in the guide holes 57 and 58.

[0127] Determining or measuring the angular position of the guide element 59 around the axis A allows us to determine the direction of the line B passing through the first and second points 43 and 44. The direction of the line B and the distance separating the first and second points constitute relative position information of the first and second lines.

[0128] A third embodiment of an arrangement 200 according to the invention is described below with reference to figure 3.

[0129] The 200 layout includes:

[0130] - a system 2,

[0131] - a kite,

[0132] - a lashing device 1, and

[0133] - a device 100 for determining the orientation and, possibly, the position of a kite in flight.

[0134] As in other embodiments, the kite comprises:

[0135] - a wing,

[0136] - a first line 41, and

[0137] - a second line 42.

[0138] Preferably, the third embodiment differs from the first or second embodiment only in that the distance L2 between, on the one hand, the first and second points 43, 44 is greater than the distance L1 separating the proximal ends 45, 46 of lines 41 and 42. A sufficiently large distance L2 improves the accuracy of detecting the relative position of lines 41 and 42.

[0139] Regardless of the embodiment and variant, the distance L2 between the first and second points 43, 44 is advantageously greater than the distance L1 separating the proximal ends 45, 46 of lines 41 and 42.

[0140] Regardless of the embodiment and variant, the distance L2 between the first and second points 43, 44 is advantageously less than 1 m. Thanks to the solutions described below, it is possible to implement an execution method for determining the orientation of a kite 3 in flight as described below.

[0141] The determination process includes:

[0142] - a step of determining the relative position of the first and second lines in a reference frame R, in particular in a geocentric reference frame or in the reference frame of a device 2 towed by the kite 3, and

[0143] - a step of determining kite orientation values ​​3 using the relative position of the first and second lines, the kite orientation values ​​including a kite yaw angle value or a kite leading edge orientation value 31.

[0144] Preferably, the method further includes a step of determining kite position values ​​3 using the relative position of the first and second lines, the kite position values ​​including:

[0145] - an azimuth angle value of wing 31 of the kite, and / or

[0146] - a wing elevation angle value of 31 of the kite.

[0147] Preferably, the step of determining a relative position of the first and second lines in a reference frame R includes a step of determining a relative position of a first point 43 of the first line 41 relative to a second point 44 of the second line 42 in the reference frame R.

[0148] Preferably, the first point is maintained at a constant distance from the second point. Advantageously:

[0149] - the first point 43 is a fixed point (as in the first embodiment) or a moving point on the first line 41 (as in the second embodiment), and / or

[0150] - the second point 44 is a fixed point (as in the first embodiment) or a moving point on the second line 42 (as in the second embodiment).

[0151] Alternatively, the first point and the second point can be movable relative to each other in a plane at least substantially perpendicular to the first and second lines.

[0152] The step of determining a relative position of the first and second lines in a reference frame R is advantageously carried out by the measuring element 5 linking the first point 43 and the second point 44 and by the logical processing unit 6.

[0153] In the various embodiments and variants, a distance D between:

[0154] - on the one hand, points 43 and 44 are located on the lines, and

[0155] - On the other hand, the anchoring or securing of the lines to the structure, i.e., the proximal ends 45, 46, is advantageously:

[0156] - greater than 0.1 m or 0.5 m, and / or

[0157] - less than 5 m or 2 m.

[0158] It follows from what has been described above that the solution makes it possible to determine the relative position of two lines, or two points of two lines, without having to determine the positions of each of the lines relative to a given frame, such as a geocentric frame or a frame of system 2.

Claims

DEMANDS 1. A method for determining the orientation of a kite (3) in flight, the kite being held by at least a first line (41) and a second line (42), the method of determination comprising: - a step of determining, by a measuring element (5), a relative position of the first and second lines in a reference frame (R), in particular in a geocentric reference frame or in a reference frame of a system (2), in particular a system towed by the kite (3), and - a step of determining, by a logical processing unit (6), kite orientation values ​​(3) using the relative position of the first and second lines, the kite orientation values ​​including a kite yaw angle value of a wing (31) of the kite, the step of determining a relative position of the first and second lines in a reference frame (R) comprising a step of determining a relative position of a first point (43) of the first line (41) relative to a second point (44) of the second line (42) in the reference frame (R), and the first point being maintained at a constant distance from the second point.

2. A method according to claim 1, characterized in that it comprises a step of determining the position values ​​of the kite (3) using the relative position of the first and second lines, the position values ​​of the kite including: - a wing azimuth angle value (31) of the kite, and / or - a wing elevation angle value (31) of the kite.

3. A method according to any one of the preceding claims, characterized in that: - the first point (43) is a fixed point on the first line (41) and the second point (44) is a fixed point on the second line (42), or - the first point (43) is a moving point on the first line (41) and the second point (44) is a moving point on the second line (42).

4. A method for determining the orientation of a kite (3) in flight, the kite being held by at least a first line (41) and a second line (42), the method of determination comprising: - a determination step, in particular by means of a measuring element (5), of a relative position of the first and second lines in a reference frame (R), in particular in a geocentric reference frame or in a reference frame of a system (2), in particular a system towed by the kite (3), and - a determination step, in particular by a logical processing unit (6), of kite orientation values ​​(3) using the relative position of the first and second lines, the kite orientation values ​​including a kite yaw angle value of a wing (31) of the kite.

5. A method according to claim 4, characterized in that it comprises a step of determining the position values ​​of the kite (3) using the relative position of the first and second lines, the position values ​​of the kite including: - a wing azimuth angle value (31) of the kite, and / or - a wing elevation angle value (31) of the kite.

6. Method according to claim 4 or 5, characterized in that the step of determining a relative position of the first and second lines in a reference frame (R) includes a step of determining a relative position of a first point (43) of the first line (41) relative to a second point (44) of the second line (42) in the reference frame (R).

7. A method according to claim 6, characterized in that the first point is maintained at a constant distance from the second point or in that that the first point and the second point are mobile relative to each other in a plane at least substantially perpendicular to the first and second lines.

8. A method according to claim 6 or 7, characterized in that: - the first point (43) is a fixed point or a moving point on the first line (41), and / or - the second point (44) is a fixed point or a moving point on the second line (42).

9. Method according to any one of the preceding claims, characterized in that the step of determining a relative position of the first and second lines in a reference frame (R) is carried out by a measuring element (5) linking the first point (43) and the second point (44).

10. A method according to any one of the preceding claims, characterized in that the measuring element (5) comprises a means (51) for measuring the orientation of the measuring element in a geocentric reference frame, in particular an accelerometer (51), especially a 3-axis accelerometer, and optionally a magnetometer (54). 1 1. Method according to any one of the preceding claims, characterized in that the measuring element (5) comprises a means (52) for measuring the orientation of the measuring element, in particular a sensor (52) for measuring an angle of rotation around the direction (A) of traction of the kite, of rotation.

12. Device (100) for determining the orientation of a kite (3) in flight, characterized in that it comprises hardware and / or software elements (5, 51, 52, 53, 55, 54, 6, 61, 62, 63) implementing the method according to one of the preceding claims, in particular hardware (5, 51, 52, 53, 54, 55, 6, 61, 62, 63) and / or software elements designed to implement the method according to one of the preceding claims.

13. Layout (200) comprising: - a system (2), - a kite (3), - a lashing device (1), and - a determination device (100) according to the preceding claim.

14. Product computer program comprising program code instructions recorded on a computer-readable medium to implement the method according to any one of claims 1 to 1 1 when said program is running on a computer.

15. Computer-readable data recording medium (62) on which is recorded a computer program comprising program code instructions for implementing the method according to any one of claims 1 to 11.

16. Signal from a data carrier, carrying the computer program product according to claim 14.

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