Aerial suspension device, water surface floating device, and control method

Abstract

To provide an aerial suspension device, etc., that can be used even if the aircraft does not maintain hovering flight. [Solution] The aerial suspension device comprises a suspension device, a water surface levitation device installed between the aircraft and the suspension device, and a suspension cable connecting the aircraft and the suspension device, wherein the water surface levitation device has a hollow section through which the suspension cable passes, and an inner membrane separating the hollow section from the outer sheath, and when fluid is injected into the filling section, which is the space between the outer sheath and the inner membrane, the filling section expands and the suspension cable comes into contact with the inner surface of the inner membrane, thereby restricting the longitudinal movement of the suspension cable, and when fluid flows out from the filling section, the filling section contracts and the suspension cable and the inner surface of the inner membrane cease to come into contact, thereby allowing the suspension cable to move in the longitudinal direction, the suspension cable restraint tube, a control unit that controls the injection and discharge of fluid according to a control signal, and a communication unit that receives the control signal.

Description

Technical Field

[0001] The present disclosure relates to an airborne suspension device, a water surface floating device, and a control method.

Background Art

[0002] Airborne suspension devices that are suspended and used from flying objects such as helicopters and drones are known. For example, Patent Document 1 describes a suspended sonar device that is locked to a flying object by a cable. While using the suspended sonar device, the flying object continuously performs hovering flight. Hovering flight is a flight mode that maintains a stationary state at low altitude.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The technology described in Patent Document 1 requires the flying object to continuously perform hovering flight at low altitude while using the airborne suspended sonar device. However, depending on weather conditions such as strong winds and turbulent airflows, it is highly dangerous to continuously perform hovering flight at low altitude for a long time.

[0005] An object of the present disclosure is to provide an airborne suspension device, a water surface floating device, and a control method that can be used without the flying object continuously performing hovering flight.

Means for Solving the Problems

[0006] An aerial suspension device according to one aspect of the present disclosure comprises a suspension device suspended from an aircraft into the water, a water surface buoyancy device installed between the aircraft and the suspension device, and a suspension cable connecting the aircraft and the suspension device and passing through the water surface buoyancy device, wherein the water surface buoyancy device has a hollow section through which the suspension cable passes, and an inner membrane separating the hollow section from the outer sheath, and when fluid is injected into the filling section, which is the space between the outer sheath and the inner membrane, the filling section expands and the inner diameter of the inner membrane decreases, causing the suspension cable to come into contact with the inner surface of the inner membrane and thereby restricting the longitudinal movement of the suspension cable, and when fluid is released from the filling section, the filling section contracts and the inner diameter of the inner membrane increases, causing the suspension cable to no longer come into contact with the inner surface of the inner membrane and thereby enabling the longitudinal movement of the suspension cable, and a control unit that controls the injection and release of fluid into the suspension cable restraint tube in accordance with a control signal from the aircraft, and a communication unit that receives the control signal.

[0007] A water surface levitation device in one aspect of the present disclosure is a water surface levitation device installed between an aircraft and a suspension device in an aerial suspension device suspended in water from an aircraft, and comprises a suspension cable restraining tube having a hollow section through which a suspension cable connecting the aircraft and the suspension device passes, and an inner membrane separating the hollow section from the outer shell, wherein when fluid is injected into the filling section, which is the space between the outer shell and the inner membrane, the filling section expands and the inner diameter of the inner membrane decreases, causing the suspension cable to come into contact with the inner surface of the inner membrane and thereby restricting the longitudinal movement of the suspension cable, and when fluid is released from the filling section, the filling section contracts and the inner diameter of the inner membrane increases, causing the suspension cable to no longer come into contact with the inner surface of the inner membrane and thereby enabling the longitudinal movement of the suspension cable, and comprises a control unit that controls the injection and release of fluid into the suspension cable restraining tube in accordance with a control signal from the aircraft, and a communication unit that receives the control signal.

[0008] A control method in one aspect of the present disclosure is a control method for an aerial suspension device comprising a suspension device suspended from an aircraft into the water, a water surface buoyancy device installed between the aircraft and the suspension device, and a suspension cable connecting the aircraft and the suspension device and passing through the water surface buoyancy device, wherein the control method is to unwind the suspension cable from the aircraft until the suspension device reaches a predetermined suspension depth, and when the suspension device reaches the suspension depth, a fluid is injected into the filling portion, which is the space between the outer sheath and the inner membrane of a suspension cable restraint tube having a hollow portion through which the suspension cable passes and an inner membrane that separates the hollow portion from the outer sheath, and when the filling portion expands due to the injection of fluid into the filling portion, the inner diameter of the inner membrane becomes smaller and the suspension cable comes into contact with the inner surface of the inner membrane, thereby restricting the longitudinal movement of the suspension cable, and the control method is to unwind the excess length of the suspension cable from the aircraft. [Effects of the Invention]

[0009] According to this disclosure, it is possible to provide an aerial suspension device, a water surface levitation device, and a control method that can be used by an aircraft without maintaining hovering flight. [Brief explanation of the drawing]

[0010] [Figure 1] This is a conceptual diagram illustrating the aerial suspension device described in this disclosure. [Figure 2] This figure shows an example of the configuration of a water surface buoyancy device in this disclosure. [Figure 3] This figure shows an example of the configuration of a suspension cable restraint tube in this disclosure. [Figure 4] This figure shows an example of the configuration of the suspension cable in this disclosure. [Figure 5] This figure shows an example of the configuration of an aerial suspension device in this disclosure. [Figure 6] This figure shows an example of a flight route while waiting in the air as described in this disclosure. [Figure 7] A flowchart illustrating an example of the operation of an aerial suspension device in this disclosure. [Figure 8]A flowchart illustrating an example of the operation of an aerial suspension device in this disclosure. [Figure 9] This is a conceptual diagram illustrating the operation of an aircraft when an aerial suspension device does not have a water surface levitation device. [Figure 10] This is a conceptual diagram illustrating the operation of an aircraft when an aerial suspension device does not have a water surface levitation device. [Figure 11] This is a conceptual diagram illustrating the operation of an aircraft when an aerial suspension device does not have a water surface levitation device. [Figure 12] This figure shows an example of the configuration of an aerial suspension device in this disclosure. [Figure 13] A flowchart illustrating an example of the operation of an aerial suspension device in this disclosure. [Modes for carrying out the invention]

[0011] The embodiments described below will be described in detail with reference to the drawings. The embodiments described below have technically preferred limitations for carrying out the disclosure, but do not limit the scope of the invention. In all the drawings used in the description of the embodiments below, the same parts are denoted by the same reference numerals unless there is a specific reason not to. In the embodiments below, similar configurations and operations may be omitted from repeated descriptions.

[0012] [First Embodiment]

[0013] (composition) First, the configuration of the aerial suspension device in the first embodiment will be described while referring to the drawings. FIG. 1 is a conceptual diagram for explaining the aerial suspension device in the present disclosure. In the present embodiment, the aerial suspension device will be described as an aerial suspension sonar device, but this is just an example. The suspension device used by suspending it from an aircraft does not necessarily have to be a sonar device. In the aerial suspension device 1 of the present disclosure, the suspension device 4 is coupled by a suspension cable 3 from an aircraft 2 which is the mother aircraft. The suspension device 4 is fixed at a predetermined depth by a water surface floating device 10. The method by which the water surface floating device 10 fixes the suspension cable 3 will be described later. The water surface floating device 10 is provided between the aircraft 2 and the suspension device 4. The aircraft is, for example, an aircraft such as a helicopter, a multicopter, a drone, etc.

[0014] The water surface floating device 10 is fixed at a predetermined position of the suspension cable 3. The predetermined position is a position where the length L1 of the suspension cable 3 from the suspension device 4 to the water surface floating device 10 is longer than the vertical distance LD from the sea surface to the layer depth. That is, the water surface floating device 10 fixes the suspension cable 3 at a position where the depth of the suspension device 4 is deeper than the depth from the sea surface to the layer depth. The layer depth is the lower surface of the thermocline in the sea. The thermocline is a region where a rapid change in water temperature is observed in the range from the sea surface to a certain depth. The thermocline is generated due to the overheating of the sea surface by solar radiation energy or the cooling of the sea surface due to the low temperature environment in winter, resulting in a temperature difference in the seawater region near the sea surface. When the suspension device is a sonar, if the suspension device 4 is arranged within the range of the thermocline, underwater sound waves will diffuse. Therefore, in order to prevent this, it is preferable that the length L1 of the suspension cable 3 is longer than the vertical distance LD from the sea surface to the layer depth. Also, the length L2 of the suspension cable 3 from the aircraft 2 to the water surface floating device 10 is set arbitrarily. It is preferable that the length L2 of the suspension cable 3 ensures a sufficient extra length for the aircraft 2 to fly safely.

[0015] <Water surface floating device> FIG. 2 is a diagram showing an example of the configuration of the water surface floating device in the present disclosure. The water surface floating device 10 includes a suspension cable passage port 11, a suspension cable pulley 12, a suspension cable restraint tube 13, a cylinder 14, an electromagnetic valve control unit 15, a fluid injection electromagnetic valve 16, a fluid discharge electromagnetic valve 17, a fluid discharge port 18, and a transceiver antenna 19. In the example shown in FIG. 2, the water surface floating device 10 is cylindrical, but is not limited to this shape.

[0016] The suspension cable passage port 11 is a passage port for the suspension cable 3 to extend from the upper part of the water surface floating device 10 toward the flying object 2. The suspension cable passage port 11 opens from the upper center to the end of the cylindrical water surface floating device 10. The opening width of the suspension cable passage port 11 is larger than the diameter of the suspension cable 3.

[0017] The suspension cable pulley 12 is a pulley for preventing excessive force and frictional heat from being applied to the suspension cable 3 during the standby flight of the flying object 2. The radius of the suspension cable pulley 12 is a value larger than the allowable bending radius of the suspension cable 3.

[0018] The suspension cable restraint tube 13 is a tube for fixing the suspension cable 3 to the water surface floating device 10. The suspension cable restraint tube 13 is realized by a material having elasticity and airtightness. For example, the suspension cable restraint tube 13 is realized by synthetic rubber.

[0019] Figure 3 shows an example of the configuration of a suspended cable restraint tube in this disclosure. Figure 3 is a cross-sectional view of the suspended cable restraint tube 13 in the short direction. As shown in Figure 3, when the suspended cable restraint tube 13 is cylindrical, the short direction is the radial direction. In the example shown in Figure 3, the cross-section in the short direction of the suspended cable restraint tube 13 is a perfect circle, but it is not limited to this. For example, the cross-section in the short direction of the suspended cable restraint tube 13 may be an ellipse, a triangle, a square, a polygon, etc. As shown in Figure 3, the suspended cable restraint tube 13 has an outer sheath 131, an inner membrane 132, a hollow section 133, and a filling section 134. The outer sheath 131 is a protective membrane for maintaining the watertightness of the suspended cable restraint tube. The inner membrane 132 is a membrane for separating the hollow section 133 and the filling section 134. The hollow section 133 is a space through which the suspended cable 3 passes. The filling section 134 is the space between the outer sheath 131 and the inner membrane 132. The filling section 134 is connected to the cylinder 14 and filled with fluid. When fluid is injected into the filling section 134, the filling section 134 expands, and the inner diameter of the inner membrane 132 decreases. As a result, the suspension cable 3 comes into contact with the inner surface of the inner membrane 132, restricting the longitudinal movement of the suspension cable 3 and fixing the suspension cable 3 to the water surface buoyancy device 10. Furthermore, when fluid flows out of the filling section 134, the filling section 134 contracts, and the inner diameter of the inner membrane 132 increases. As a result, the suspension cable 3 no longer comes into contact with the inner surface of the inner membrane 132, allowing the suspension cable 3 to move longitudinally. In its initial state, that is, when the aerial suspension device 1 is lowered into the sea, the suspension cable restraint tube 13 is in a state where no fluid is injected and the suspension cable 3 can move in the longitudinal direction. The size of the suspension cable restraint tube 13 is set as appropriate and is not limited, but for example, it has a diameter of approximately 3 cm, a hollow section diameter of approximately 1.5 cm, a height of 0.1 to 0.3 m, and a volume of approximately 200 ml.

[0020] Cylinder 14 is a cylinder for storing fluid. The fluid stored in the cylinder can be any fluid that expands the suspension cable restraint tube 13 in the short direction, and may be a gas, liquid, or quasi-fluid. The fluid is particularly preferably a pressurized gas. For example, pressurized gases include compressed gases with a pressure of 1 megapascal (MPa) or more at normal operating temperature or 1 megapascal (MPa) or more at 35°C, compressed acetylene gases with a pressure of 0.2 megapascal (MPa) or more at normal operating temperature or 0.2 megapascal (MPa) or more at 15°C, and liquefied gases with a pressure of 0.2 megapascal (MPa) or more at normal operating temperature or 0.2 megapascal (MPa) at 35°C or below. Furthermore, pressurized gases also include certain liquefied gases with a pressure exceeding 0 megapascal (MPa) at 35°C (liquefied hydrogen cyanide, liquefied methyl bromide, liquefied ethylene oxide). When the fluid is a pressurized gas, the internal pressure of the suspension cable restraint tube 13 is about 5 atmospheres. Therefore, when approximately 1000 ml of pressurized gas at 1 atmosphere is ejected, the suspension cable restraint tube 13 expands in the shorter direction. In this case, the time required for the suspension cable restraint tube 13 to expand and contract in the shorter direction is about 1 second, which has little impact on the time it takes for the aircraft 2 to lower the aerial suspension device 1 into the sea and to retrieve it. Furthermore, the fluid is preferably an inert gas, such as nitrogen or carbon dioxide.

[0021] The electromagnetic valve control unit 15 controls the opening and closing of the fluid injection electromagnetic valve 16 and the fluid drain electromagnetic valve 17. The electromagnetic valve control unit 15 is communicated with the transmitting and receiving antenna 19, the fluid injection electromagnetic valve 16, and the fluid drain electromagnetic valve 17 via a transmission medium. The electromagnetic valve control unit 15 receives the opening and closing control signals for the fluid injection electromagnetic valve 16 and the fluid drain electromagnetic valve 17 via the transmitting and receiving antenna 19, and controls the opening and closing of the valves according to the received control signals. The electromagnetic valve control unit 15 includes a battery to supply the power necessary for controlling the opening and closing of the valves.

[0022] The fluid injection solenoid valve 16 is a valve for injecting fluid into the suspension cable restraint tube 13. The fluid injection solenoid valve 16, which is installed at the connection point between the cylinder 14 and the suspension cable restraint tube 13, opens and closes in accordance with the power supplied from the solenoid valve control unit 15.

[0023] The fluid draining solenoid valve 17 is a valve for releasing the fluid injected into the suspension cable restraint tube 13 from the water surface buoyancy device 10. The fluid draining solenoid valve 17 is installed at the connection point between the suspension cable restraint tube 13 and the fluid discharge port 18. The fluid draining solenoid valve 17 opens and closes in accordance with the power supplied from the solenoid valve control unit 15.

[0024] The fluid discharge port 18 is an opening located at the top of the water surface buoyancy device 10. When the fluid release electromagnetic valve 17 opens, the fluid inside the suspension cable restraint tube 13 is released from the fluid discharge port 18.

[0025] The transmitting / receiving antenna 19 receives control signals from the aircraft 2. The transmitting / receiving antenna 19 is an antenna for wireless communication between the suspension cable control unit 24 and the electromagnetic valve control unit 15 mounted on the aircraft 2. The transmitting / receiving antenna 19 is installed on the upper surface of the water surface buoyancy device 10.

[0026] <Suspension Cable> Figure 4 shows an example of the configuration of a suspension cable in this disclosure. The suspension cable 3 has a transmission medium 31, a buoyancy material 32, and an outer sheath 33. The thickness of the suspension cable 3 is set as appropriate and is not limited, but as an example, its diameter is 1 cm.

[0027] The transmission medium 31 is a medium for communicating between the aircraft 2 and the suspended device 4. For example, the transmission medium 31 can be made of optical fiber or electric wire. The transmission medium 31 is enclosed by the buoyancy material 32.

[0028] The buoyancy material 32 is a cable structure material that provides buoyancy for the suspended cable to float in the sea. The buoyancy material 32 is made of a material that has flexibility and elasticity to withstand winding and unwinding by the aircraft 2. For this reason, the buoyancy material 32 also serves as a buffer for the transmission medium 31. Furthermore, it is preferable that the buoyancy material 32 is lightweight in order to increase buoyancy. Specifically, it is preferable that the specific gravity of the suspended cable 3 be lighter than the specific gravity of seawater. For example, the buoyancy material 32 can be made of foamed urethane or the like.

[0029] The outer sheath 33 is for maintaining the watertightness of the suspended cable 3. The outer sheath 33 is made of a waterproof material. For example, the outer sheath 33 is made of fluororesin or the like.

[0030] <Aerial hanging device> Figure 5 shows an example of the configuration of an aerial suspension device in this disclosure. The aerial suspension device 1 is housed inside the aircraft 2. Specifically, the aircraft 2 houses a suspension cable drum 21, a motor 22, a transmission medium 23, a suspension cable control unit 24, a relay pulley 25, a suspension cable 3, a suspension pulley 26, a water surface buoyancy device 10, a suspension device 4, a radar 27, a radio altimeter 28, and a transmitting / receiving antenna 29.

[0031] The suspended cable drum 21 is a cable drum used to wind up the suspended cable 3 inside the aircraft 2. The suspended cable drum 21 is rotated by the motor 22.

[0032] The motor 22 rotates the suspension cable drum 21 in either the winding or unwinding direction of the suspension cable 3, according to a control signal from the suspension cable control unit 24. The rotation speed of the motor 22 is also specified by a control signal from the suspension cable control unit 24. The motor 22 and the suspension cable control unit 24 are communicated together by a transmission medium 23.

[0033] The suspension cable control unit 24 controls the rotation of the suspension cable drum 21 and the opening and closing of the electromagnetic valve control unit 15 of the water surface buoyancy device 10. The suspension cable control unit 24 may also be implemented as part of the functions of an automatic flight control system if one is installed on the aircraft 2.

[0034] The suspension cable control unit 24 transmits a control signal to the motor 22 to rotate the suspension cable drum 21 in the direction of winding or unwinding the suspension cable 3. The control signal includes information on the rotation direction and rotation speed of the motor 22. If the motor 22 is a hydraulic motor, the suspension cable control unit 24 also transmits a control signal to control the opening and closing of the electromagnetic valve that controls the hydraulic pressure that rotates the motor 22.

[0035] Furthermore, the suspension cable control unit 24 calculates the radius of the flight path while the aircraft is waiting in the air. Figure 6 is a diagram showing an example of a flight path while the aircraft is waiting in the air according to this disclosure. The radius r of the flight path while the aircraft is waiting in the air is a length that does not pose a risk of damage to the suspension cable 3, and is calculated by the suspension cable control unit 24. The procedure for the suspension cable control unit 24 to calculate the radius of the flight path while the aircraft is waiting in the air is described below. First, the suspension cable control unit 24 measures the length of the suspension cable that is paid out from the rotation speed of the suspension cable drum 21. Next, the suspension cable control unit 24 calculates the radius of the flight path in which the aircraft 2 will fly while waiting in the air, based on the distance between the aircraft 2 and the water surface flotation device 10, the length of the suspension cable 3 in the sea, and the flight altitude of the aircraft 2. The suspension cable control unit 24 notifies the pilot of the aircraft 2 of the calculated flight path while waiting in the air, for example. The distance between the aircraft 2 and the water surface flotation device 10 is measured, for example, by radar 27. The length of the underwater suspension cable is measured, for example, by a water pressure depth gauge mounted on the suspension device. The flight altitude of the aircraft 2 is measured, for example, by a radio altimeter 28.

[0036] The relay pulley 25 acts as a relay to guide the suspension cable 3, which is unwound from the suspension cable drum 21, to the suspension pulley 26. However, if there are no obstacles in the straight line between the suspension cable drum 21 and the suspension pulley 26, the aerial suspension device 1 does not need to be equipped with the relay pulley 25.

[0037] The suspension pulley 26 is a pulley that supports the weight of the water surface buoyancy device 10 and the suspended device 4. The radius of the suspension pulley 26 is set to a value greater than the allowable bending radius of the suspension cable 3.

[0038] Radar 27 measures the straight-line distance between the aircraft 2 and the water surface levitation device 10. Radar 27 is installed on the underside of the aircraft 2. Radar 27 detects the position of the water surface levitation device 10 using sea surface monitoring radar waves, etc., and measures the straight-line distance between the aircraft 2 and the water surface levitation device 10 using known methods. For example, Radar 27 measures the straight-line distance between the aircraft 2 and the water surface levitation device 10 by measuring the reflection time of radio waves. Alternatively, Radar 27 measures the straight-line distance between the aircraft 2 and the water surface levitation device 10 by measuring the reflection time of laser light.

[0039] The radio altimeter 28 is a sensor that measures the flight altitude of the aircraft 2. The radio altimeter 28 is installed on the underside of the aircraft 2. The radio altimeter 28 measures the straight-line distance from the underside of the aircraft 2 to the sea surface, i.e., the flight altitude of the aircraft 2, using known methods. For example, the radio altimeter 28 measures the straight-line distance from the underside of the aircraft 2 to the sea surface by measuring the reflection time of radio waves. Alternatively, the radio altimeter 28 measures the straight-line distance from the underside of the aircraft 2 to the sea surface by measuring the reflection time of laser light.

[0040] The transmitting and receiving antenna 29 is installed on the surface of the aircraft 2. The transmitting and receiving antenna 29 is an antenna for wireless communication between the aircraft 2 and the water surface levitation device 10.

[0041] (operation) Next, the operation of the aerial suspension device 1 in this embodiment will be described with reference to Figures 7 and 8. Figures 7 and 8 are flowcharts showing an example of the operation of the aerial suspension device in this disclosure.

[0042] <Actions taken before initiating a holding flight> First, referring to Figure 7, the operation flow of the aerial suspension device 1 until the start of hovering flight will be explained. The operation of the aerial suspension device 1 shown in Figure 7 is initiated when the aircraft 2 reaches the planned position for deploying the suspension device and begins hovering flight.

[0043] First, the suspension cable control unit 24 sends a control signal to the motor to rotate it in the direction of unwinding the suspension cable 3 (step S1). The suspension cable control unit 24 continues the process of step S1 until the suspension device reaches a predetermined suspension depth (No in step S2).

[0044] When the suspended device 4 reaches a predetermined suspension depth (Yes in step S2), the suspension cable control unit 24 sends a control signal to the motor 22 to stop the rotation of the motor 22 (step S3).

[0045] Next, the electromagnetic valve control unit 15 of the water surface buoyancy device 10 closes the fluid draining electromagnetic valve 17 (step S4). The electromagnetic valve control unit 15 also opens the fluid injection electromagnetic valve 16 (step S5). These operations of the electromagnetic valve control unit 15 are performed in accordance with the control signals from the suspension cable control unit 24. The electromagnetic valve control unit 15 keeps the fluid injection electromagnetic valve 16 open until the suspension cable restraint tube 13 is filled with fluid (No in step S6). When the filling section 134 of the suspension cable restraint tube 13 is filled with fluid (Yes in step S6), the electromagnetic valve control unit 15 closes the fluid injection electromagnetic valve 16 (step S7). As a result of the processing in steps S4 to S7, the filling portion 134 of the suspension cable restraint tube 13 expands, reducing the inner diameter of the inner membrane 132. The friction caused by the contact between the suspension cable 3 and the inner membrane 132 restricts the longitudinal movement of the suspension cable 3, thereby fixing the suspension cable 3 to the water surface buoyancy device 10, and the water surface buoyancy device 10 supports the underwater weight of the suspension device 4.

[0046] Next, the suspension cable control unit 24 rotates the motor 22 in the direction that the suspension cable drum 21 pays out the excess length of the suspension cable 3 (step S8). The process in step S8 ensures that the excess length of the suspension cable 3 necessary for the aircraft 2 to maintain a waiting flight in the air.

[0047] Next, the suspension cable control unit 24 notifies the pilot of the aircraft 2 of the command to cancel hovering flight and the radius of the waiting flight route in the air (step S9). By performing the above series of processes, the aircraft 2 can perform waiting flight in the air without hovering within the range of the excess length of the suspension cable 3 extended in the air and on the sea surface.

[0048] <Operations during retrieval> Next, with reference to Figure 8, the operation flow during the retrieval of the aerial suspension device 1 will be explained. The operation flow shown in Figure 8 begins when the underwater search by the suspension device 4 is completed.

[0049] First, the electromagnetic valve control unit 15 opens the fluid discharge electromagnetic valve 17 (step S10). This causes fluid to be discharged from the fluid discharge port 18, the filling portion 134 of the suspension cable restraint tube 13 to contract, the inner diameter of the inner membrane 132 to increase, and the suspension cable 3 and the inner membrane 132 no longer come into contact, allowing the suspension cable 3 to move in the longitudinal direction. The electromagnetic valve control unit 15 waits until the fluid is discharged from and the suspension cable restraint tube 13 has contracted (No in step S11). For example, the electromagnetic valve control unit 15 stores in advance the time required until the fluid is completely discharged and waits until the required time has elapsed. Once the fluid is discharged from and the suspension cable restraint tube 13 has contracted (Yes in step S11), the process proceeds to step S12.

[0050] Next, the suspension cable control unit 24 transmits a control signal to the motor 22 to rotate the suspension cable drum 21 in the direction of winding up the suspension cable 3 (step S12). As a result, the aerial suspension device 1 is hoisted onto the aircraft 2.

[0051] The aerial suspension device of this embodiment is configured as described above. Next, the effects of the aerial suspension device of this embodiment will be explained with reference to Figures 9 to 11.

[0052] Figures 9 to 11 are conceptual diagrams illustrating the operation of an aircraft when an aerial suspension device does not have a water surface buoyancy device. An aerial suspension device without a water surface buoyancy device will continue to hover at a low altitude, as shown in Figure 9, while the suspension device is exploring the seabed. The suspension device moves in the direction of the ocean current, as shown in Figure 10. Therefore, the aircraft's hovering position must also move at the same speed as the ocean current. In this case, as shown in Figure 11, the aircraft must move its hovering position in accordance with the ocean current while pointing its nose into the wind to avoid crosswinds, which is dangerous for the aircraft's pilot. Furthermore, if the wind direction and the ocean current direction do not coincide, it is difficult to continue hovering at a low altitude. For this reason, if an aerial suspension device does not have a water surface buoyancy device, a situation may arise where the suspension of the suspension device must be abandoned.

[0053] On the other hand, the aerial suspension device of this embodiment is equipped with a water surface buoyancy device. The water surface buoyancy device comprises a suspension cable restraint tube, an electromagnetic valve control unit (hereinafter also referred to as the control unit), and a transmitting / receiving antenna (hereinafter also referred to as the communication unit). The suspension cable restraint tube has a hollow section through which the suspension cable passes, and an inner membrane that separates the hollow section from the outer sheath. When fluid is injected into the filling section, which is the space between the outer sheath and the inner membrane of the suspension cable restraint tube, the filling section expands, reducing the inner diameter of the inner membrane, and the suspension cable comes into contact with the inner surface of the inner membrane, thereby restricting the longitudinal movement of the suspension cable. Also, when fluid flows out of the filling section of the suspension cable restraint tube, the filling section contracts, increasing the inner diameter of the inner membrane, and the suspension cable no longer comes into contact with the inner surface of the inner membrane, thereby enabling the longitudinal movement of the suspension cable. The control unit controls the injection and release of fluid into the suspension cable restraint tube in accordance with control signals from the aircraft. The communication unit receives control signals. When fluid is injected into the suspension cable restraint tube, as shown in Figure 1, the longitudinal movement of the suspension cable is restricted, and the suspension cable is fixed to the water surface buoyancy device. In other words, the suspension device is fixed to the water surface buoyancy device. While the suspension device is fixed to the water surface buoyancy device, the aircraft does not need to hover at low altitude to keep the suspension device fixed in place. In other words, the aerial suspension device of this embodiment can be used without the aircraft needing to continue hovering, thanks to the above configuration.

[0054] One embodiment of this water surface buoyancy device further includes a cylinder for storing fluid. The fluid is a pressurized gas. Because the fluid is a pressurized gas, the time required for the fluid to fill or drain from the suspension cable restraint tube can be reduced. In other words, according to one embodiment of this water surface buoyancy device, the time required to drop the aerial suspension device into the sea and the time required to retrieve the aerial suspension device from the sea can be reduced. In other words, according to one embodiment of this aerial suspension device, the time required for the aircraft to maintain hovering flight can be reduced.

[0055] One embodiment of this water surface buoyancy device further comprises a fluid discharge port, a fluid injection solenoid valve, and a fluid discharge solenoid valve. The fluid discharge port is a passage for releasing fluid from the suspension cable restraint tube. The fluid injection solenoid valve is installed at the connection point between the cylinder and the suspension cable restraint tube. The fluid discharge solenoid valve is installed at the connection point between the suspension cable restraint tube and the fluid discharge port. The control unit controls the opening and closing of the fluid injection solenoid valve and the fluid discharge solenoid valve according to a control signal. With the above configuration, the control unit in the aerial suspension device of this embodiment is able to control the injection and discharge of fluid into the suspension cable restraint tube.

[0056] An aerial suspension device according to one aspect of this embodiment further comprises a suspension cable control unit that transmits control signals. When the suspension device reaches a predetermined suspension depth, the suspension cable control unit transmits a control signal to control the injection of fluid into the suspension cable restraint tube. It is preferable that the suspension device can be fixed at a certain depth. For example, if the suspension device is a suspension sonar, it is preferable to suspend it at a suspension depth greater than the depth from the sea surface to the depth of the sea layer. The aerial suspension device according to one aspect of this embodiment can be fixed at a certain depth because, when the suspension device reaches a predetermined suspension depth, it transmits a control signal to control the injection of fluid into the suspension cable restraint tube.

[0057] An aerial suspension device according to one aspect of this embodiment further comprises a suspension cable drum and a suspension cable control unit. The suspension cable drum is driven by a motor and winds up the suspension cable inside the aircraft. The suspension cable control unit controls the motor to rotate the suspension cable in a direction that unwinds or winds it up from the aircraft. The suspension cable control unit transmits a control signal to control the rotation of the suspension cable in a direction that unwinds it from the aircraft until the suspension device reaches a predetermined suspension depth, and when the suspension cable restraint tube expands and the suspension cable is fixed, it transmits a control signal to control the rotation of the excess length of the suspension cable in a direction that unwinds it from the aircraft. In an aerial suspension device according to one aspect of this embodiment, the time it takes for the fluid to fill the suspension cable restraint tube and the time it takes for the fluid to drain are short. As a result, the time it takes to drop the suspension device into the sea and the time it takes to retrieve the suspension device from the sea are short. For this reason, according to an aerial suspension device according to one aspect of this embodiment, the time that the aircraft can continue hovering can be shortened.

[0058] In one embodiment of this aerial suspension device, the inside of the suspension cable is filled with buoyancy material. This reduces the specific gravity of the suspension cable to less than that of seawater, causing the suspension cable to float on the surface of the sea. If the specific gravity of the suspension cable is greater than that of seawater and the excess length of the suspension cable sinks into the sea, there is a risk of damage to the suspension cable due to the load placed on it when the aircraft is in a waiting position in the air. According to one embodiment of this aerial suspension device, since the suspension cable floats on the surface of the sea, the load placed on the suspension cable is reduced, and damage to the suspension cable can be suppressed.

[0059] An aerial suspension device according to one aspect of this embodiment further includes a notification unit. The notification unit notifies the radius of the aircraft's waiting flight route above the ground. The suspension cable control unit measures the length of the suspension cable extended using the rotation speed of the suspension cable drum, and calculates the radius of the aircraft's waiting flight route above the ground using the distance between the aircraft and the water surface buoyancy device, the length of the suspension cable underwater, and the aircraft's flight altitude. This allows the aircraft's operator to understand the most fuel-efficient cruising route when the aircraft is waiting above the ground. As a result, the aerial suspension device according to one aspect of this embodiment can improve fuel efficiency during use.

[0060] In one embodiment of this aerial suspension device, the control unit further includes a battery that supplies power required to open and close the fluid injection solenoid valve and the fluid drain solenoid valve. This allows the control unit to control the opening and closing of the fluid injection solenoid valve and the fluid drain solenoid valve.

[0061] [Second Embodiment]

[0062] (composition) In this embodiment, we will describe an aerial suspension device 100, which has a simplified configuration compared to the aerial suspension device in the first embodiment. In the following description, parts that are the same as in the first embodiment will be omitted as appropriate.

[0063] Figure 12 shows an example of the configuration of an aerial suspension device in this disclosure. As shown in Figure 12, the aerial suspension device 100 comprises a suspension cable 3, a suspension device 4, and a water surface buoyancy device 200. The suspension device 4 is a device that is suspended from the aircraft into the water. The water surface buoyancy device 200 is installed between the aircraft and the suspension device 4. The suspension cable 3 connects the aircraft and the suspension device 4 and passes through the water surface buoyancy device 200.

[0064] The water surface buoyancy device 200 includes a suspension cable restraint tube 203, a control unit 205, and a communication unit 209. The suspension cable restraint tube 203 has a hollow section through which the suspension cable 3 passes, and an inner membrane that separates the hollow section from the outer sheath. When fluid is injected into the filling section, which is the space between the outer sheath and the inner membrane, the filling section expands, reducing the inner diameter of the inner membrane and causing the suspension cable to come into contact with the inner surface of the inner membrane, thereby restricting the longitudinal movement of the suspension cable. When fluid flows out of the filling section, the filling section contracts, increasing the inner diameter of the inner membrane and preventing the suspension cable from coming into contact with the inner surface of the inner membrane, thereby allowing the suspension cable to move longitudinally. The control unit 205 controls the injection and discharge of fluid into the suspension cable restraint tube 203 in response to a control signal from the aircraft. The control unit is the same as the electromagnetic valve control unit 15 in the first embodiment. The communication unit 209 receives the control signal. The communication unit 209 is the same as the transmitting and receiving antenna 19 in the first embodiment.

[0065] (operation) Next, with reference to Figure 13, a control method for the aerial suspension device 100 will be described. Figure 13 is a flowchart showing an example of the operation of the aerial suspension device in this disclosure.

[0066] First, the aerial suspension device 100 controls the suspension cable connecting the aircraft and the suspension device to be paid out in the direction away from the aircraft until the suspension device reaches a predetermined suspension depth (step S21). Next, when the suspension device reaches the suspension depth, the aerial suspension device 100 injects fluid into the filling section, which is the space between the outer sheath and the inner membrane of the suspension cable restraint tube, which has a hollow section through which the suspension cable passes and an inner membrane that separates the hollow section from the outer sheath (step S22). Next, when the filling section expands due to the injection of fluid into the filling section, reducing the inner diameter of the inner membrane and causing the suspension cable to come into contact with the inner surface of the inner membrane, thereby restricting the longitudinal movement of the suspension cable, the aerial suspension device 100 controls the excess length of the suspension cable to be paid out in the direction away from the aircraft (step S23).

[0067] The aerial suspension device of this embodiment is configured as described above. The aerial suspension device includes a water surface buoyancy device. The water surface buoyancy device includes a suspension cable restraint tube, a control unit, and a communication unit. When fluid is injected into the suspension cable restraint tube, the longitudinal movement of the suspension cable is restricted. In other words, the suspension device is fixed to the water surface buoyancy device. While the suspension device is fixed to the water surface buoyancy device, the aircraft does not need to hover at low altitude to keep the suspension device fixed in place. In other words, the aerial suspension device of this embodiment can be used without the aircraft needing to continue hovering, thanks to the above configuration.

[0068] Although the present disclosure has been described above with reference to the embodiments described, the present disclosure is not limited to the embodiments described above. Various modifications to the structure and details of the present disclosure can be made that will be understood by those skilled in the art within the scope of the present disclosure. For example, although multiple operations are described sequentially in the form of a flowchart, the order in which they are described does not limit the order in which the multiple operations are performed. Therefore, when implementing each embodiment, the order of the multiple operations can be changed to the extent that it does not impair the content.

[0069] Some or all of the above embodiments may also be described as follows: (Note 1) A suspension device that is lowered into the water from the aircraft, A water surface buoyancy device installed between the aforementioned flying object and the aforementioned suspension device, The aircraft and the suspension device are connected, and the suspension cable passes through the water surface buoyancy device, The aforementioned water surface buoyancy device is A suspension cable restraint tube having a hollow portion through which the suspension cable passes, and an inner membrane separating the hollow portion from the outer sheath, wherein when a fluid is injected into a filling portion which is the space between the outer sheath and the inner membrane, the filling portion expands and the inner diameter of the inner membrane decreases, causing the suspension cable to come into contact with the inner surface of the inner membrane and thereby restricting the longitudinal movement of the suspension cable, and when the fluid flows out from the filling portion, the filling portion contracts and the inner diameter of the inner membrane increases, causing the suspension cable to no longer come into contact with the inner surface of the inner membrane and thereby enabling the longitudinal movement of the suspension cable, A control unit that controls the injection and discharge of the fluid into the suspension cable restraint tube in response to a control signal from the aircraft, A communication unit that receives the aforementioned control signal, Aerial hanging device. (Note 2) The water surface flotation device further comprises a cylinder for storing the fluid, The aforementioned fluid is a pressurized gas, as described in Appendix 1 of the aerial suspension device. (Note 3) The aforementioned water surface buoyancy device is A fluid discharge port for releasing the fluid from the suspension cable restraint tube, A fluid injection solenoid valve is installed at the connection point between the cylinder and the suspension cable restraint tube, The system further includes a fluid draining electromagnetic valve installed at the connection point between the suspension cable restraint tube and the fluid discharge port, The aerial suspension device as described in Appendix 2, wherein the control unit controls the opening and closing of the fluid injection solenoid valve and the fluid discharge solenoid valve in accordance with the control signal. (Note 4) The suspension cable control unit that transmits the aforementioned control signal is further provided, The aerial suspension device according to any one of appendices 1 to 3, wherein the suspension cable control unit transmits the control signal for controlling the injection of fluid into the suspension cable restraint tube when the suspension device reaches a predetermined suspension depth. (Note 5) A suspension cable drum driven by a motor for winding up the suspension cable inside the aircraft, An aerial suspension device according to any one of appendices 1 to 4, further comprising: a suspension cable control unit that controls the motor to rotate the suspension cable in a direction that unwinds or winds it from the aircraft. (Note 6) The aerial suspension device as described in Appendix 5, wherein the suspension cable control unit transmits a control signal to control the suspension cable to rotate in a direction that unwinds it from the aircraft until the suspension device reaches a predetermined suspension depth, and when the suspension cable restraint tube expands and the suspension cable is fixed, transmits a control signal to control the excess length of the suspension cable to rotate in a direction that unwinds it from the aircraft. (Note 7) The suspension device described in any one of the appendices 1 to 6, wherein the inside of the suspension cable is filled with buoyancy material. (Note 8) The aircraft further comprises a notification unit that notifies the radius of the waiting flight route above the aircraft, The aerial suspension device as described in Appendix 5 or Appendix 6, wherein the suspension cable control unit measures the length of the suspension cable unfurled using the rotational speed of the suspension cable drum, and calculates the radius of the flight path above the aircraft using the distance between the aircraft and the water surface buoyancy device, the length of the suspension cable underwater, and the flight altitude of the aircraft. (Note 9) The aerial suspension device as described in Appendix 2, wherein the control unit further comprises a battery that supplies power required for opening and closing the solenoid valve for fluid injection and the solenoid valve for fluid discharge. (Note 10) A water surface buoyancy device installed between an aerial suspension device that is suspended in water from an aerial vehicle, the aerial suspension device being suspended from the aerial vehicle and the suspension device, A suspension cable restraint tube having a hollow section through which a suspension cable connecting the aircraft and the suspension device passes, and an inner membrane separating the hollow section from the outer sheath, wherein when fluid is injected into the filling section, which is the space between the outer sheath and the inner membrane, the filling section expands and the inner diameter of the inner membrane decreases, causing the suspension cable to come into contact with the inner surface of the inner membrane and thereby restricting the longitudinal movement of the suspension cable, and when the fluid flows out from the filling section, the filling section contracts and the inner diameter of the inner membrane increases, causing the suspension cable to no longer come into contact with the inner surface of the inner membrane and thereby enabling the longitudinal movement of the suspension cable, A control unit that controls the injection and discharge of the fluid into the suspension cable restraint tube in response to a control signal from the aircraft, A communication unit that receives the aforementioned control signal, A water surface buoyancy device equipped with the following features. (Note 11) A control method for an aerial suspension device comprising: a suspension device suspended from an aircraft into the water; a water surface buoyancy device installed between the aircraft and the suspension device; and a suspension cable connecting the aircraft and the suspension device and passing through the water surface buoyancy device, The suspension device is controlled to extend the suspension cable in the direction away from the aircraft until it reaches a predetermined suspension depth. When the suspension device reaches the suspension depth, fluid is injected into the filling portion, which is the space between the outer sheath and the inner membrane of the suspension cable restraint tube, which has a hollow portion through which the suspension cable passes and an inner membrane that separates the hollow portion from the outer sheath. When the fluid is injected into the filling section, the filling section expands, reducing the inner diameter of the inner membrane, causing the suspension cable to come into contact with the inner surface of the inner membrane, thereby restricting the longitudinal movement of the suspension cable. The excess length of the suspension cable is then controlled to be unfurled away from the aircraft. Control method.

[0070] Furthermore, in the above appendices, some or all of the configurations described in Appendices 2 to 9, which are dependent on Appendice 1, may also be dependent on Appendices 10 and 11 in the same way as those described in Appendices 2 to 9. Moreover, not limited to Appendices 1, 10, and 11, some or all of the configurations described as appendices may be made dependent on various hardware or systems in the same manner, without departing from the embodiments described above. [Explanation of Symbols]

[0071] 1,100 Aerial hanging device 2 flying objects 3. Suspension Cable 4 Hanging equipment 10,200 Water surface buoyancy devices 11. Cable passage opening for suspended cables 12 Suspension Cable Pulley 13, 203 Suspension Cable Restraint Tube 14,204 cylinders 15, 205 Electromagnetic valve control unit (control unit) 16. Solenoid valve for fluid injection 17. Solenoid valve for fluid draining 18 Fluid discharge port 19, 209 Transmitting and Receiving Antennas (Communication Section) 21. Suspended Cable Drum 22 motors 23 Transmission medium 24. Suspended Cable Control Unit 25 Relay pulley 26 Hanging pulley 27 Radar 28 Radio altimeter 29 Transmitting and Receiving Antennas 31. Transmission medium 32 Buoyancy material 33. Outer skin (sheath)

Claims

1. A suspension device that is lowered into the water from the aircraft, A water surface buoyancy device installed between the aforementioned flying object and the aforementioned suspension device, The aircraft and the suspension device are connected, and the suspension cable passes through the water surface buoyancy device, The aforementioned water surface buoyancy device is A suspension cable restraint tube having a hollow portion through which the suspension cable passes, and an inner membrane separating the hollow portion from the outer sheath, wherein when a fluid is injected into a filling portion which is the space between the outer sheath and the inner membrane, the filling portion expands and the inner diameter of the inner membrane decreases, causing the suspension cable to come into contact with the inner surface of the inner membrane and thereby restricting the longitudinal movement of the suspension cable, and when the fluid flows out from the filling portion, the filling portion contracts and the inner diameter of the inner membrane increases, causing the suspension cable to no longer come into contact with the inner surface of the inner membrane and thereby enabling the longitudinal movement of the suspension cable, A control unit that controls the injection and discharge of the fluid into the suspension cable restraint tube in response to a control signal from the aircraft, A communication unit that receives the aforementioned control signal, Aerial hanging device.

2. The water surface flotation device further comprises a cylinder for storing the fluid, The aerial suspension device according to claim 1, wherein the fluid is a pressurized gas.

3. The aforementioned water surface buoyancy device is A fluid discharge port for releasing the fluid from the suspension cable restraint tube, A fluid injection solenoid valve is installed at the connection point between the cylinder and the suspension cable restraint tube, The system further includes a fluid draining electromagnetic valve installed at the connection point between the suspension cable restraint tube and the fluid discharge port, The aerial suspension device according to claim 2, wherein the control unit controls the opening and closing of the fluid injection solenoid valve and the fluid draining solenoid valve in accordance with the control signal.

4. The suspension cable control unit that transmits the aforementioned control signal is further provided, The aerial suspension device according to claim 1, wherein the suspension cable control unit transmits the control signal for controlling the injection of the fluid into the suspension cable restraint tube when the suspension device reaches a predetermined suspension depth.

5. A suspension cable drum driven by a motor for winding up the suspension cable inside the aircraft, The aerial suspension device according to claim 1, further comprising: a suspension cable control unit that controls the motor to rotate the suspension cable in a direction that unwinds or winds it from the aircraft.

6. The aerial suspension device according to claim 5, wherein the suspension cable control unit transmits the control signal to control the suspension cable to rotate in a direction that unwinds it from the aircraft until the suspension device reaches a predetermined suspension depth, and when the suspension cable restraint tube expands and restricts the longitudinal movement of the suspension cable, transmits the control signal to control the excess length of the suspension cable to rotate in a direction that unwinds it from the aircraft.

7. The aerial suspension device according to claim 1, wherein the inside of the suspension cable is filled with a buoyancy material.

8. The aircraft further comprises a notification unit that notifies the radius of the waiting flight route above the aircraft, The aerial suspension device according to claim 5 or 6, wherein the suspension cable control unit measures the length of the suspension cable unfurled using the rotational speed of the suspension cable drum, and calculates the radius of the flight path above the aircraft using the distance between the aircraft and the water surface buoyancy device, the length of the suspension cable underwater, and the flight altitude of the aircraft.

9. A water surface buoyancy device installed between an aerial suspension device that is suspended in water from an aerial vehicle, the aerial suspension device being suspended from the aerial vehicle and the suspension device, A suspension cable restraint tube having a hollow section through which a suspension cable connecting the aircraft and the suspension device passes, and an inner membrane separating the hollow section from the outer sheath, wherein when fluid is injected into the filling section, which is the space between the outer sheath and the inner membrane, the filling section expands and the inner diameter of the inner membrane decreases, causing the suspension cable to come into contact with the inner surface of the inner membrane and thereby restricting the longitudinal movement of the suspension cable, and when the fluid flows out from the filling section, the filling section contracts and the inner diameter of the inner membrane increases, causing the suspension cable to no longer come into contact with the inner surface of the inner membrane and thereby enabling the longitudinal movement of the suspension cable, A control unit that controls the injection and discharge of the fluid into the suspension cable restraint tube in response to a control signal from the aircraft, A communication unit that receives the aforementioned control signal, A water surface buoyancy device equipped with the following features.

10. A control method for an aerial suspension device comprising: a suspension device suspended from an aircraft into the water; a water surface buoyancy device installed between the aircraft and the suspension device; and a suspension cable connecting the aircraft and the suspension device and passing through the water surface buoyancy device, The suspension device is controlled to extend the suspension cable in the direction away from the aircraft until it reaches a predetermined suspension depth. When the suspension device reaches the suspension depth, fluid is injected into the filling portion, which is the space between the outer sheath and the inner membrane of the suspension cable restraint tube, which has a hollow portion through which the suspension cable passes and an inner membrane that separates the hollow portion from the outer sheath. When the fluid is injected into the filling section, the filling section expands, reducing the inner diameter of the inner membrane, causing the suspension cable to come into contact with the inner surface of the inner membrane, thereby restricting the longitudinal movement of the suspension cable. The excess length of the suspension cable is then controlled to be unfurled away from the aircraft. Control method.

Images