Waterborne floating body

Abstract

The present invention provides a configuration in which, in a waterborne floating body that lifts a tethered flying body, a wind pressure difference angle with respect to the direction of travel of the floating body is made without using a rudder in the water under the floating body, to make the center plate generate lift in a direction that cancels lateral force from the tethered flying body. In a waterborne floating body that lifts a tethered flying body with a tether, a center plate extends from the bottom surface of a hull floating on the water surface into the water, a winch mechanism for paying out and taking up the tether connected to the tethered flying body is disposed on the upper side of the hull, a tether catching mechanism that catches the tether on the hull is separated from the winch and is movable around the winch mechanism, and a tether catching position control mechanism is configured to control the position of the tether catching mechanism to balance lateral force from the tether on the hull and lift borne by the center plate.

Description

Technical Field

[0001] The present invention relates to a floating body that navigates on water and lifts tethered flying objects such as kites into the air, and more specifically, to a structure for controlling the direction of travel of the floating body. Background Technology

[0002] Typically, in large ships using wind-powered propulsion systems (sails, rotors, etc.), the ship may turn during navigation due to tilting. Therefore, steering control (applying an angle to the rudder when sailing straight) is sometimes employed to generate a torque that counteracts this turning. However, in this case, applying an angle to the rudder also generates propulsive drag. Therefore, Patent Document 1 proposes a configuration where, in a multihull ship with buoyancy bodies on both sides of the main hull, when the sails are hoisted, the propulsive force generated on the sails also generates a torque that tilts the hull in the roll direction. Thus, if the hull tilts, one side of the buoyancy body sinks while the other side floats, creating a difference in fluid resistance between the left and right sides of the buoyancy body, thereby generating a torque that counteracts turning.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2023-152466 Summary of the Invention

[0004] In recent years, a method has been proposed to launch tethered flying objects such as kites from floating bodies such as ships and generate electricity using the wind power generated by the tethered flying objects, and this method is gradually being put into practical use. In the floating body that launches the tethered flying object, when the direction of the tethered flying object's ascent is laterally to the floating body, the tethered flying object exerts a lateral force on the floating body. Therefore, in the case of a floating body with a center plate (or keel) at the bottom, the following configuration is adopted: the bow of the floating body is tilted relative to the direction of travel of the floating body, so that the center plate generates lift to counteract the lateral force from the tethered flying object (giving it a yaw angle). Regarding this, if a rudder in the water below the floating body is used to steer the bow relative to the direction of travel of the floating body, as mentioned above, this will create propulsion resistance and reduce energy efficiency.

[0005] As detailed later, in a floating hull that lifts a moored aircraft, if the direction of the fulcrum of the mooring line connecting the moored aircraft to the hull of the floating hull (mooring fulcrum) and the position of the moored aircraft differs from the direction connecting the moored aircraft and the winch mechanism, or the direction of the connection point on the floating hull connecting the mooring fulcrum and the mooring line (mooring connection point), the yaw component of the floating hull at the mooring fulcrum is affected by the traction force from the moored aircraft, thus generating a yaw moment on the floating hull. Therefore, if the position of the mooring fulcrum is adjusted to apply a yaw moment that tilts the yaw direction of the floating hull toward the direction of the lift force that counteracts the lateral force from the moored aircraft on the center plate, then a rudder is not required, and thus at least a portion of the lateral force from the moored aircraft can be counteracted without increasing propulsion drag, thereby improving energy efficiency.

[0006] In view of the above, the main objective of the present invention is to provide a configuration in which, in a water-based floating body that lifts a tethered aircraft, a wind pressure differential angle relative to the direction of travel of the floating body can be achieved without using a rudder in the water below the floating body, so that the center plate generates lift in a direction that counteracts the lateral force from the tethered aircraft.

[0007] According to the present invention, the above-mentioned problem is achieved by a floating body that lifts a tethered aircraft secured by a tether, and includes:

[0008] The hull of the ship, which floats on the water;

[0009] A center plate that extends from the bottom of the hull into the water;

[0010] A winch mechanism, disposed on the upper side of the hull, is used to release and reel in the mooring rope connected to the moored aircraft.

[0011] A tether-catching mechanism that catches the tether on the hull, spaced apart from the winch, and controllably fixed relative to the hull position around the winch mechanism; and

[0012] A tethered capture position control mechanism is configured to control the position of the tethered capture mechanism on the hull.

[0013] The mooring capture position control mechanism is configured to control the position of the mooring capture mechanism on the hull to balance the lateral force from the mooring rope on the hull and the lift force borne by the center plate.

[0014] In the above configuration, "floating body" refers to a vessel or other floating body that floats on water or at sea, having a hull that floats on the water surface. Any structure, such as a mast, sail, or stern, can be installed on the deck of the hull. The launched moored aircraft can be a kite or balloon, etc., and is moored by a tether released from a winch mechanism located on the upper side of the hull. The "tether" can be any tether commonly used in this field, for example, a tether made of millimeter-scale ultra-high-strength polyethylene fiber. As mentioned above, the "center plate" is a plate-like component extending from the bottom of the hull into the water, which helps to generate a lateral force (lift) in the direction that counteracts the lateral external forces acting on the hull. Furthermore, the center plate performs the same function as what is called a keel or simply a keel. The "winch mechanism" can be any type of mechanism, typically having a rotating reel for winding the tether, and a rotation control mechanism that appropriately controls the rotation of the rotating reel based on, for example, the tension acting on the tether, configured to adjust the length of the tether released from the rotating reel to the moored aircraft. The "tether capture mechanism" is configured to be positioned further outward from the hull than the winch mechanism, and to hold the tether in such a way that the tether extending from the winch mechanism to the moored aircraft is slidably captured in its extension direction; that is, the lateral aspect of the tether is constrained, while allowing the tether to slide in its length direction. Furthermore, the tether capture mechanism is fixed to the hull, and therefore its fixed position is controlled by a tether capture position control mechanism. The "tether capture position control mechanism" can be a computer device, configured as described above, to control the position of the tether capture mechanism on the hull to balance the lateral force from the tether on the hull with the lift force borne by the center plate.

[0015] According to the above-described configuration of the present invention, the tether connecting the moored aircraft and the winch mechanism is captured by the tether capture mechanism on the hull. Therefore, the position of the tether capture mechanism becomes the fulcrum of the tether on the hull. Furthermore, when the position of the tether capture mechanism, i.e., the fulcrum of the tether on the hull, shifts from the line connecting the moored aircraft and the winch mechanism, a force component is generated in the tether that aims to extend the tether along the line connecting the moored aircraft and the winch mechanism. This force component generates a rotational torque around the winch mechanism, i.e., a yaw torque. As a result, the hull rotates in the yaw direction relative to the direction of travel, thus creating a wind pressure differential angle on the center plate, and the center plate exerts a lateral force (lift) on the hull.

[0016] Therefore, in this invention, as described above, the tether capture position control mechanism controls the position of the tether capture mechanism on the hull to balance the lateral force from the tether on the hull and the lift force borne by the center plate, i.e., to generate a yaw moment so that the lift force generated on the center plate is opposite in direction and approximately equal to the lateral traction force generated by the moored aircraft on the hull. In this case, it is not necessary to steer the rudder in the water below the float (the direction of the rudder can be parallel to the direction of travel) to generate lift force in the direction that counteracts the lateral force from the moored aircraft, thus not increasing the propulsion drag generated by the rudder and improving energy efficiency.

[0017] In the above-described configuration of the present invention, as a mechanism for controlling the position of the tethered capture mechanism, a guide rail extending along a path surrounding the winch mechanism can be provided on the deck of the hull. The tethered capture mechanism is movably mounted on the guide rail, and the tethered capture position control mechanism is configured to control the position of the tethered capture mechanism on the guide rail. In this configuration, the guide rail can be a circular or elliptical ring-shaped component fixedly disposed on the hull in a manner surrounding the winch mechanism, and the tethered capture mechanism can slide on the guide rail to control its position. The mechanism for moving the tethered capture mechanism on the guide rail can be of any form. In this case, the position control of the tethered capture mechanism can be achieved by controlling the angle of rotation of the tethered capture mechanism around the center (winch mechanism) on the guide rail. In this case, the control quantity is one, thereby making the position control of the tethered capture mechanism easy.

[0018] Furthermore, as another mechanism for controlling the position of the tethered capture mechanism, a guide rail extending along the path surrounding the winch mechanism can be installed on the deck of the hull. The guide rail is rotatable around the winch mechanism, and the tethered capture mechanism is fixed to the guide rail. The tethered capture position control mechanism is configured to control the position of the tethered capture mechanism on the hull by rotating the guide rail. In this case, the position of the tethered capture mechanism is controlled by controlling the amount of rotation of the guide rail; the control amount remains singular, thus facilitating the position control of the tethered capture mechanism.

[0019] In the above configuration, the position of the tethering mechanism on the hull can be controlled in various ways to balance the lateral force from the tether on the hull and the lift force borne by the center plate. For example, when the lateral force from the tether on the hull and the lift force borne by the center plate are balanced, the actual direction of travel of the hull is consistent with the target direction of travel. Therefore, a direction detection mechanism such as a GPS device can be installed on the floating body to detect the direction of travel of the hull. The tethering position control mechanism is configured to control the position of the tethering mechanism on the hull so that the actual direction of travel of the hull is consistent with the target direction of travel. In this case, in order to reduce the deviation between the target direction of travel and the actual direction of travel of the hull, the position of the tethering mechanism can be controlled by feedback control of this deviation. Alternatively, when the lateral force from the mooring line on the hull balances the lift force borne by the center plate, the lateral acceleration or yaw rate of the hull becomes zero. Therefore, a lateral acceleration detection mechanism or a yaw rate detection mechanism can be installed on the floating body to detect the lateral acceleration or yaw rate of the hull. The mooring line capture position control mechanism is configured to control the position of the mooring line capture mechanism on the hull so that the lateral acceleration or yaw rate of the hull converges to zero. In this case, to make the detected lateral acceleration or yaw rate of the hull zero, the position of the mooring line capture mechanism can be controlled by feedback control of the lateral acceleration or yaw rate.

[0020] Invention Effects

[0021] Thus, according to the configuration of the present invention, in the floating body that lifts the moored aircraft, a mechanism is established to generate a yaw moment based on the traction force of the moored aircraft by adjusting the position of the fulcrum of the tether connecting the moored aircraft to the hull, and to generate lift by creating a wind pressure difference angle on the center plate, thereby suppressing the lateral force exerted by the moored aircraft on the hull. In this configuration, there is no need to steer the rudder in the water below the floating body, thus it is expected to improve energy efficiency without increasing propulsion drag.

[0022] Other objects and advantages of the present invention will become apparent from the following description of preferred embodiments of the invention. Attached Figure Description

[0023] Figure 1 (A) is a schematic rear view of the floating body to which this embodiment applies. Figure 1 (B) is a schematic top view of one type of floating body applicable to this embodiment. Figure 1 (C) is a schematic top view of another type of floating body applicable to this embodiment.

[0024] Figure 2(A) is a block diagram showing one configuration for controlling the position of the tethering catcher in the floating body to which this embodiment is applicable. Figure 2 (B) is a block diagram showing another configuration for controlling the position of the tethering catcher in the floating body to which this embodiment is applicable.

[0025] Figure 3 (A) is a diagram illustrating the forces and moments acting on the water-floating body to which this embodiment applies. Figure 3 (B) is a diagram illustrating the relationship between the position of the tethered aircraft in this embodiment and the direction of the tether fulcrum (the position of the tether's capture part), and the direction of the connection between the tether fulcrum and the tether connection point (the position of the winch device).

[0026] Symbol Explanation

[0027] 1-Floating body, 2-Hull, 2t-Main hull, 2z-Side hull, 2s-Bottom of the hull, 3-Tethered flying body (kite), 4-Tether rope, 5-Wind device (tether rope connection part), 6-Center plate, 7-Guide rail, 7a-Guide rail rotating device, 8-Tether rope capture part, 10-Tether rope fulcrum control device, 11-Sensor (GPS device or gyroscope sensor). Detailed Implementation

[0028] Hereinafter, several preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same symbols denote the same parts.

[0029] Composition of floating bodies on water

[0030] refer to Figure 1 (A) Figure 1In (B), in the floating body 1 applicable to this embodiment, a winch device 5 for releasing and retrieving a mooring rope 4 is basically provided on the upper side of the hull 2 ​​floating on the water surface w. The mooring rope 4 is used to moor a tethered flying object 3, which may be a kite or a balloon. The hull 2 ​​may be a monohull, but as shown in the figure, it may also be a multihull with side hulls 2z provided next to the main hull 2t. A mast 2m and a sail 2c are conventionally provided on the upper side of the main hull 2t, and a center plate (or keel, fin) 6 extending into the water is provided at the bottom 2s of the main hull 2t. Furthermore, in this embodiment, as a mechanism for controlling the position of the fulcrum of the tether connected to the moored aircraft 3 on the hull 2, a tether-catching part 8 is provided on the upper side of the hull 2. This part is provided with a guide rail 7 that is approximately parallel to the deck of the hull 2, and the position on the guide rail 7 is controllably movable. The guide rail 7 is a circular (or elliptical) ring-shaped guide rail with the winch device 5 approximately at its center. The tether-catching part 8 can be configured to catch the tether 4 while allowing displacement of the tether 4 in its extension direction. Thus, the tether 4 extends from the winch device 5 towards the moored aircraft 3 via the tether-catching part 8 on the guide rail 7. By controlling the position of the tether-catching part 8 on the guide rail 7, the offset of the tether 4 from the winch device 5 to the tether-catching part 8 (section 4a) and from the tether-catching part 8 to the moored aircraft 3 (section 4b) is controlled. Furthermore, if the directions of part 4b and part 4a are offset, as will be explained in detail later, the mooring rope 4 applies a rotational force to the guide rail 7 via the mooring rope catcher 8 in the direction in which the offset is to be reduced, thereby generating a yaw moment on the fixed hull 2 ​​of the guide rail 7.

[0031] Regarding the control of the position of the tethering capture part 8 on the guide rail 7, specifically, for example, it can be configured such that a rotating roller (not shown) that rotates on the guide rail 7 is provided in the tethering capture part 8. The tethering capture part 8 can move on the guide rail 7 by rotating the rotating roller, as shown by arrow p. The position of the tethering capture part 8 is controlled by controlling the amount of rotation of the rotating roller. Figure 2 As shown in (A), the displacement of the position of the tether capture unit 8 or the rotation of the rotating roller can be controlled as follows: based on the direction of travel of the floating body 1 or the lateral acceleration or yaw rate of the hull 2 ​​detected by the GPS device or gyroscope sensor 11, a control command c, which may be a computer device, is sent to the tether capture unit 8.

[0032] In addition, such as Figure 1As shown in (C), the mechanism for controlling the position of the tethering catch 8 on the hull 2 ​​can be as follows: the tethering catch 8 is fixed to a guide rail 7, and the guide rail 7 rotates around the winch assembly 5, thereby changing the position of the tethering catch 8. In this case, the guide rail 7 can, for example, be configured to engage with a rotating roller 7a, and rotate around the winch assembly 5 by the rotation of the rotating roller 7a, as shown by arrow q. Figure 2 As shown in (B), the position of the tethered capture unit 8 on the hull 2 ​​can be controlled based on the direction of travel of the floating body 1 or the lateral acceleration or yaw rate of the hull 2 ​​detected by the GPS device or gyroscope sensor 11, and the rotation amount of the rotating roller 7a can be controlled by the control command c of the tethered fulcrum control device 10.

[0033] Control structure of the position of the tethered capture unit

[0034] In the vessel of this embodiment, as described above, in the floating body on the water where the moored aircraft 3 is raised, as a force that suppresses the lateral force of the moored aircraft 3 acting on the hull 2 ​​via the mooring rope 4, the center plate 6 at the bottom of the hull 2 ​​generates lift. For this purpose, by controlling the position of the mooring rope catcher 8, which becomes the fulcrum of the mooring rope 4 in the hull 2, a yaw moment is generated that causes the bow of the hull 2 ​​to tilt away from the moored aircraft 3 relative to the direction of travel, so that the center plate 6 has a wind pressure difference angle.

[0035] More specifically, in this embodiment, such as Figure 3 As shown in (A), a winch device 5 is provided on the upper side of the hull 2, which is used to lift the moored aircraft 3 and tether it with a tether 4. Around the winch device 5, which serves as the fulcrum of the tether 4, a tether-catching part 8 is configured to move along a path (rail) 7 around the winch device 5, which serves as the connection point of the tether. In this configuration, firstly, when the moored aircraft 3 is tilted laterally relative to the direction of travel V of the hull and lifted, a lateral force Fk is applied to the moored aircraft 3 via the tether 4. In this case, in order for the hull 2 ​​to move forward in the direction of travel V, the bow f of the hull 2 ​​needs to be tilted away from the side where the moored aircraft 3 is lifted, thereby generating a yaw moment Mγ in the hull 2, which in turn generates a lift force Fc in the center plate 6 in the opposite direction to the lateral force Fk. Regarding this yaw moment Mγ, conventionally it is generated by steering the rudder 2l at the stern. However, in this embodiment, it is generated by controlling the tether fulcrum 8 along path 7 to a position further aft of the hull 2 ​​than the line connecting the winch device 5 and the moored aircraft 3. Thus, if the tether fulcrum 8 is moved further aft of the hull 2 ​​than the line connecting the winch device 5 and the moored aircraft 3, then... Figure 3As shown in (B), relative to the direction d (4b) of the tether portion 4b between the mooring body 3 and the tether fulcrum 8, the direction d (4a) of the tether portion 4a between the tether fulcrum 8 and the connection point 5 of the tether shifts backward (B). To eliminate this shift, a force is generated in the direction that causes the tether 4 to shift forward (opposite to B), thus generating a yaw moment Mγ through the component along the path 7 of this force. Furthermore, the tilting of the bow stops when the yaw moment Mγ is balanced by the reaction force generated on the center plate 6. The rudder 2l can be adjusted to be parallel to the direction of travel V.

[0036] In control, a yaw moment Mγ can be generated to tilt the bow so that the lateral force Fk from the moored flying body 3 is balanced with the lift Fc from the center plate. Regarding this, the yaw moment Mγ varies due to the mooring fulcrum 8 on path 7; therefore, the target value of the position of the mooring fulcrum 8 on path 7 can be determined as the position where the lateral force Fk from the moored flying body 3 is balanced with the lift Fc from the center plate.

[0037] Therefore, in one embodiment, when the lateral force Fk from the tethered aircraft 3 is balanced with the lift Fc of the center plate, the direction of travel V of the floating body is consistent with the target direction Vt, and thus the target value of the position of the tether fulcrum 8 on path 7 can be determined. More specifically, as described above, a GPS device can be equipped on the floating body 1 to detect the actual direction of travel V, and the displacement of the position of the tether fulcrum 8 on path 7 can be determined by feedback control of the angular deviation from the target direction Vt, so as to reduce the difference between the actual direction of travel V and the target direction Vt. Furthermore, in another embodiment, when the lateral force Fk from the tethered aircraft 3 is balanced with the lift Fc of the center plate, the lateral acceleration or yaw rate of the floating body becomes 0, and thus the target value of the position of the tether fulcrum 8 on path 7 can be determined. More specifically, lateral acceleration sensors such as gyroscopes or yaw rate sensors can be installed on the floating body 1 to determine the displacement of the mooring point 8 on path 7, thereby reducing the magnitude of the lateral acceleration or yaw rate of the hull 2. This feedback control can be implemented using any control method under any circumstances, such as optimal regulators, PID control, Bang-Bang control, or using modern controllers or AI.

[0038] Thus, according to the configuration of this embodiment, in a floating body that lifts a tethered aircraft, a wind pressure difference angle relative to the direction of travel of the floating body can be achieved without operating the rudder in the water below the floating body, so that the center plate generates lift that at least partially counteracts the lateral force from the tethered aircraft. This embodiment can be applied not only to kites for aerial wind power generation but also to floating bodies that lift various tethered aircraft.

[0039] The above description relates to the embodiments of the present invention, but those skilled in the art can easily make various modifications and changes. The present invention is not limited to the embodiments illustrated above. Obviously, the present invention can be applied to various devices without departing from the concept of the present invention.

Claims

1. A floating body for levitizing a tethered flying body secured by a tethering rope, the floating body being characterized by comprising: The hull of the ship, which floats on the water; A center plate that extends from the bottom of the hull into the water; A winch mechanism, disposed on the upper side of the hull, is used to release and reel in the mooring rope connected to the moored aircraft. A tether-catching mechanism that catches the tether on the hull, spaced apart from the winch and controllably fixed relative to the hull position around the winch mechanism; and A tethered capture position control mechanism is configured to control the position of the tethered capture mechanism on the hull. The mooring capture position control mechanism is configured to control the position of the mooring capture mechanism on the hull to balance the lateral force from the mooring rope on the hull and the lift force borne by the center plate.

2. The floating body according to claim 1, characterized in that, It also includes a travel direction detection mechanism for detecting the travel direction of the hull, and the tether capture position control mechanism is configured to control the position of the tether capture mechanism on the hull so that the actual travel direction of the hull is consistent with the target travel direction.

3. The floating body according to claim 1, characterized in that, It also includes a mechanism for detecting the lateral acceleration or yaw rate of the hull, wherein the tether capture position control mechanism is configured to control the position of the tether capture mechanism on the hull so that the lateral acceleration or yaw rate of the hull converges to 0.

4. The floating body according to claim 1, characterized in that, It also includes a guide rail extending along a path around the winch mechanism on the deck of the hull, the tether capture mechanism being movably mounted on the guide rail, and the tether capture position control mechanism being configured to control the position of the tether capture mechanism on the guide rail.

5. The floating body according to claim 1, characterized in that, It also includes a guide rail extending along a path around the winch mechanism on the deck of the hull, the guide rail being rotatable about the winch mechanism, the tether capture mechanism being fixed to the guide rail, and the tether capture position control mechanism being configured to control the position of the tether capture mechanism on the hull by rotating the guide rail.

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