Methods of dynamically controlling airflow behind a carrier aircraft to redirect air flow during an in-flight recovery of an unmanned aerial vehicle and an apparatus therefor

An apparatus is provided for dynamically controlling airflow behind a carrier aircraft to redirect air flow during an in-flight recovery of an unmanned aerial vehicle (UAV). The apparatus comprises a frame attached to an end portion of an arm member extending from the carrier aircraft. The apparatus comprises a plurality of vanes disposed within the frame. Each vane is controllable between an opened position and a closed position to dynamically modify the airflow behind the carrier aircraft during the in-flight recovery of the UAV. Alternatively, or in addition to, the apparatus comprises a plurality of compressed air jets disposed on the frame, wherein each jet is controllable to provide active airflow to dynamically modify the airflow behind the carrier aircraft during the in-flight recovery of the UAV.

FIELD

The present application relates to recovery of unmanned aerial vehicles, and is particularly directed to methods of dynamically controlling airflow behind a carrier aircraft to redirect air flow during an in-flight recovery of an unmanned aerial vehicle (UAV) and an apparatus therefor.

BACKGROUND

During recovery of a UAV by a carrier aircraft, air turbulence behind the carrier aircraft could cause unpredictable and unstable behaviors of the UAV. Behavior of the UAV tends to become more unpredictable and more unstable as the UAV moves closer and closer to the carrier aircraft as the UAV is being recovered. It would be desirable to locally control the air flow/direction behind the carrier aircraft during recovery of a UAV.

SUMMARY

In one aspect, an apparatus is provided for dynamically controlling airflow behind a carrier aircraft to redirect air flow during an in-flight recovery of an unmanned aerial vehicle (UAV). The apparatus comprises a frame attached to an end portion of an arm member extending from the carrier aircraft. The apparatus comprises a plurality of vanes disposed within the frame. Each vane is controllable between an opened position and a closed position to dynamically modify the airflow behind the carrier aircraft during the in-flight recovery of the UAV.

In another aspect, an apparatus is provided for dynamically controlling airflow behind a carrier aircraft to redirect air flow during an in-flight recovery of an unmanned aerial vehicle (UAV). The apparatus comprises a frame attached to an end portion of the arm member extending from the carrier aircraft. The apparatus comprises a plurality of compressed air jets disposed on the frame, wherein each jet is controllable to provide active airflow to dynamically modify the airflow behind the carrier aircraft during the in-flight recovery of the UAV.

In yet another aspect, a method is provided of dynamically controlling airflow behind a carrier aircraft to redirect air flow during an in-flight recovery of an unmanned aerial vehicle (UAV). The method comprises controlling each vane of a plurality of vanes between an opened position and a closed position to dynamically modify the airflow behind the carrier aircraft during the in-flight recovery of the UAV.

In still another aspect, a method is provided of dynamically controlling airflow behind a carrier aircraft to redirect air flow during an in-flight recovery of an unmanned aerial vehicle (UAV). The method comprises controlling each jet of a plurality of compressed air jets to provide active airflow to dynamically modify the airflow behind the carrier aircraft during the in-flight recovery of the UAV.

Other aspects will become apparent from the following detailed description, the accompanying drawings and the appended claims.

DETAILED DESCRIPTION

The present application is directed to methods of dynamically controlling airflow behind a carrier aircraft to redirect air flow during an in-flight recovery of an unmanned aerial vehicle (UAV) and an apparatus therefor. The specific construction of the airflow control apparatus for controlling airflow behind a carrier aircraft and the specific application (e.g., military or commercial) in which the methods are implemented may vary. It is to be understood that the disclosure below provides a number of embodiments or examples for implementing different features of various embodiments. Specific examples of components and arrangements are described to simplify the present disclosure. These are merely examples and are not intended to be limiting.

By way of example, the disclosure below describes an airflow control apparatus and methods implemented for dynamically controlling airflow behind a carrier aircraft to redirect air flow during an in-flight recovery of a UAV in compliance with Federal Aviation Administration (FAA) regulations. Air turbulence is modified when air flow is redirected.

FIG. 1illustrates a perspective view of an example airflow control apparatus100for dynamically controlling airflow behind a carrier aircraft in accordance with an embodiment.FIG. 2is a perspective view, looking approximately out of the page ofFIG. 1and from the opposite side of airflow control apparatus100. Known existing structures for recovering (i.e., capturing and securing) a UAV can be modified to embody airflow control apparatus100. For example, as shown inFIGS. 1 and 2, an arm member10is extended from behind a carrier aircraft (not shown) during recovery of a UAV (also not shown). A recovery carriage in the form of enclosing “cage” structure20is disposed at the end of arm member10, and is nested within the arm member10. A tether30from behind the carrier aircraft extends alongside the arm member10and through cage structure20into the air stream behind the carrier aircraft.

A coupling structure40is attached to the end of tether30. Coupling structure40may comprise a funnel-shaped device attached to the end of the tether30. For example, coupling structure40may comprise a refueling drogue. Other types of coupling structures are possible. Coupling structure40interlocks with an associated coupling structure (not shown) mounted on the UAV. Structure and operation of various types of interlocking coupling structures are known and, therefore, will not be described.

Airflow control apparatus100includes a frame110attached to the end portion of arm member10where cage structure20is disposed. Airflow control apparatus100further includes a plurality of vanes120(FIG. 2) disposed within frame110. Controllable vanes of the plurality of vanes120shown inFIG. 2are fully closed.

Airflow control apparatus100also includes a plurality of doors130disposed on frame110. Each door of the plurality of doors130is controllable between an opened (e.g., deployed) position and a closed (e.g., stowed) position. Controllable doors of the plurality of doors130shown inFIG. 2(andFIG. 1) are fully closed. Also, each door of the plurality of doors130is controllable between an opened position and a closed position to dynamically modify the airflow behind the carrier aircraft and thereby to redirect air flow during the in-flight recovery of the UAV.

Airflow control apparatus100is provided for dynamically controlling airflow behind the carrier aircraft to redirect air flow during an in-flight recovery of the UAV. More specifically, each vane of the plurality of vanes120is controllable between an opened position and a closed position to dynamically modify the airflow behind the carrier aircraft and thereby to redirect air flow during the in-flight recovery of the UAV.

As shown inFIGS. 1 and 2, frame110is rectangular-shaped. Each vane of the plurality of vanes120is rectangular-shaped, and each door of the plurality of doors130is also rectangular-shaped. Other shapes of frames, shapes of vanes, shapes of doors, or any combination thereof are possible.

Referring toFIG. 3, a perspective view similar to the perspective view ofFIG. 1from a slightly different angle, is illustrated. InFIG. 3, the UAV (not shown) makes initial contact with coupling structure40at a far-off distance, and the plurality of doors130and the plurality of vanes120begin to open.FIG. 3shows each door of the plurality of doors130mostly (i.e., partially) opened and each vane of the plurality of vanes120fully closed. The plurality of doors130begin to open more and more as the UAV attached to coupling structure40moves closer and closer to frame110as the UAV is being reeled in by tether30.

Referring toFIG. 4, a perspective view similar to the perspective view ofFIG. 3is illustrated. InFIG. 4, the UAV is in close proximity to airflow control apparatus100and is within “range of effect” of airflow control apparatus100. More specifically,FIG. 4shows the controllable doors of the plurality of doors130mostly opened (e.g., almost 100% opened) with some dynamic actuation to control airflow. The controllable vanes of the plurality of vanes120are mostly closed and actuating under control signals from a controller of a computer system using information provided by a number of relative position and orientation sensors, as will be described in more detail hereinbelow. Coupling structure40(and therefore the UAV) shown in the position ofFIG. 4is closer to airflow control apparatus100than shown in the position ofFIG. 3.

Referring toFIG. 5, a perspective view similar to the perspective view ofFIG. 4is illustrated. InFIG. 5, the UAV makes contact with airflow control apparatus100. More specifically,FIG. 5shows each door of the plurality of doors130in a mostly opened position, and each vane of the plurality of vanes120in a fully closed position (i.e., 100% closed off).FIG. 5also shows coupling structure40in a position that is even closer to airflow control apparatus100than shown in the position ofFIG. 4. As coupling structure40moves closer to airflow control apparatus100from the position shown inFIG. 4to the position shown inFIG. 5, each vane of the plurality of vanes120can be controlled to move anywhere between its fully opened position and its fully closed position. Moreover, each door of the plurality of doors130can be controlled to move anywhere between its fully opened position and its fully opened position.

After the UAV makes contact with airflow control apparatus100inFIG. 5and lands, the doors of the plurality of doors130begin to close on the UAV to secure the UAV in all six degrees of freedom. When the doors of the plurality of doors130are fully closed, the UAV is secured and both the UAV and coupling structure40are trapped inside airflow control apparatus100.

Referring toFIG. 6, an example computer system600capable of controlling a number of vanes, a number of doors, or any combination thereof, in accordance with an embodiment, is illustrated. Computer system600includes controller610that executes instructions stored in data storage unit612. Processing unit610may comprise any type of technology. For example, processing unit610may comprise a general-purpose electronic processor. Alternatively, processing unit610may comprise a dedicated-purpose electronic processor. Other types of processors and processing unit technologies are possible.

Data storage unit612may comprise any type of technology. For examples, data storage unit612may comprise random access memory (RAM), read only memory (ROM), solid state memory, or any combination thereof. Other types of memories and data storage unit technologies are possible.

Computer system600further includes a number of input/output (I/O) devices614that may comprise any type of technology. For example, I/O devices614may comprise a keypad, a keyboard, a touch-sensitive display screen, a liquid crystal display (LCD) screen, a microphone, a speaker, or any combination thereof. Other types of I/O devices and technologies are possible

Each of controller610, data storage unit612, and I/O devices614can be mounted on arm member10, cage structure20, frame110, any one or more of the plurality of vanes120, any one or more of the plurality of doors130, the carrier aircraft, the UAV, or any combination thereof. Other mounting locations of each of controller610, data storage unit612, and I/O devices614are possible.

Computer system600further comprises a number of relative position sensors including, for example, one or more left/right position sensors620, one or more up/down position sensors622, and one or more fore/aft sensors624. Each of sensors620,622,624can be mounted on arm member10, cage structure20, frame110, any one or more of the plurality of vanes120, any one or more of the plurality of doors130, the carrier aircraft, the UAV, or any combination thereof. Other mounting locations of each of one or more sensors620,622,624is possible.

Computer system600also comprises a number of vane actuators630. As shown inFIG. 6, “N” number of vane actuators is shown. Each vane of vane actuators630is operatively connected to one or more vanes of the plurality of vanes120. For example, all vanes of the plurality of vanes120may be operatively connected to only one vane actuator630. As another example, all vanes on one side (e.g., the left side) of frame110may be operatively connected to one vane actuator630, and all vanes on the opposite side (i.e., the right side) of frame110may be operatively connected to another vane actuator630. As yet another example, each vane of the plurality of vanes120may be operatively connected to a respective, individual vane actuator630.

Controller610is responsive to signals from the number of sensors620,622,624to control opening and closing of the plurality of doors130. Controller610is also responsive to signals from the number of sensors620,622,624to control the number of vane actuators630to control opening and closing of the plurality of vanes120. More specifically, controller610executes instructions stored in data storage unit612in response to signals from the number of sensors620,622,624to control opening and closing of the plurality of doors130and to control opening and closing of the plurality of vanes120to dynamically modify the airflow behind the carrier aircraft and thereby to redirect air flow during the in-flight recovery of the UAV.

Referring toFIG. 7, a perspective view of an example airflow control apparatus700for dynamically controlling airflow behind a carrier aircraft, and constructed in accordance with another embodiment, is illustrated. Airflow control apparatus700shown inFIG. 7is similar to airflow control apparatus100shown inFIG. 4without the plurality of doors130ofFIG. 4.FIG. 7shows each vane of a plurality of vanes720in an opened position.

Referring toFIG. 8, a perspective view similar to the perspective view ofFIG. 7is illustrated.FIG. 8shows each vane of the plurality of vanes720in a fully closed position.FIG. 8also shows coupling structure40in a position that is even closer to airflow control apparatus700than shown in the position ofFIG. 7. As coupling structure40moves closer to airflow control apparatus700from the position shown inFIG. 7to the position shown inFIG. 8, each vane of the plurality of vanes720can be controlled to move anywhere between its fully opened position to its fully closed position. Each vane of the plurality of vanes720ofFIG. 7can be controlled in the same manner as each vane of the plurality of vanes120ofFIG. 4as already described hereinabove.

Referring toFIG. 9, a perspective view, looking approximately out of the page ofFIG. 8and from the opposite side of airflow control apparatus700, is illustrated.FIG. 9shows a plurality of controllable compressed air jets950, and each vane of the plurality of vanes720of airflow control apparatus700ofFIG. 7in its fully closed position. Each jet of the plurality of controllable jets950is disposed on frame910. Each jet of the plurality of controllable jets950comprises a nozzle from which air can be controllably expelled to provide a controlled airflow. Structure and operation of controllable compressed air jets are known and, therefore, will not be described.

As shown inFIG. 9, the direction of compressed air flow from a nozzle in a direction opposite to the direction of the incoming free-streaming flow. However, it is conceivable that direction of compressed air flow from a nozzle is in a direction other than opposite to the direction of the incoming free-streaming flow. Moreover, it is conceivable that some nozzles point in the direction opposite to the direction of the incoming free-streaming flow, and some nozzles point in a direction other than opposite to the direction of the incoming free-streaming flow. It is also conceivable that each nozzle points in a direction different from the directions of all of the other nozzles.

Each jet of the plurality of jets950is controllable to provide active airflow to dynamically modify the airflow behind the carrier aircraft and thereby to redirect air flow during the in-flight recovery of the UAV. Accordingly, the controlling of the plurality of jets950complements the controlling of the plurality of vanes720to dynamically modify the airflow behind the carrier aircraft and thereby to redirect air flow during the in-flight recovery of the UAV. It is conceivable that only the plurality of jets950(and not the plurality of vanes720) be used to dynamically modify the airflow behind the carrier aircraft. Also, it is conceivable that only the plurality of vanes720(and not the plurality of jets950) be used to dynamically modify the airflow behind the carrier aircraft.

Referring toFIG. 10, a perspective view of an example airflow control apparatus1000for dynamically controlling airflow behind a carrier aircraft, and constructed in accordance with still another embodiment, is illustrated.FIG. 10shows jets of a plurality of controllable compressed air jets1050and vanes of a plurality of controllable vanes1020of airflow control apparatus1000. Each jet of the plurality of controllable jets1050is disposed on frame1010.

Each jet of the plurality of controllable jets1050is spaced apart along the lengthwise extent of frame1010, and is contoured to an outer surface of a door of a plurality of doors1030. Each jet of the plurality of controllable jets1050comprises a nozzle from which air can be controllable expelled to provide an active-controlled airflow. Structure and operation of controllable compressed air jets are known and, therefore, will not be described.

The plurality of controllable jets1050includes a lower set1052of jets and an upper set1054of jets. The lower set1052of jets points in a direction opposite to the direction of the incoming free-streaming flow. The upper set1054of jets points in the same direction as the direction of the incoming free-streaming flow. However, it is conceivable that direction of compressed air flow from any nozzle can be in a direction other than opposite to the direction of the incoming free-streaming flow or in the same direction of the incoming free-streaming flow. Moreover, it is conceivable that each nozzle points in a direction different from the directions of all of the other nozzles.

Each jet of the plurality of controllable jets1050is controlled to provide active airflow to dynamically modify the airflow behind the carrier aircraft and thereby to redirect air flow during the in-flight recovery of the UAV. Accordingly, the controlling of the plurality of jets1050complements the controlling of the plurality of vanes1020to dynamically modify the airflow behind the carrier aircraft and thereby to redirect air flow during the in-flight recovery of the UAV. It is conceivable that only the plurality of jets1050(and not the plurality of vanes1020) be used to dynamically modify the airflow behind the carrier aircraft. Also, it is conceivable that only the plurality of vanes1020(and not the plurality of jets1050) be used to dynamically modify the airflow behind the carrier aircraft.

Referring toFIG. 11, an elevational view of an example airflow control apparatus1100for dynamically controlling airflow behind a carrier aircraft, and constructed in accordance with yet another embodiment, is illustrated.FIG. 12is an elevational view, looking approximately in the direction of arrow “12” inFIG. 11, and shows each vane of a plurality of controllable, arcuate-shaped vanes1220in a closed position. Each of the plurality of arcuate-shaped vanes1220is disposed in four quadrants of circular-shaped frame1110.

Controllable compressed air jets, such as described hereinabove with reference to other embodiments, can be used in the embodiment ofFIGS. 11 and 12. For example, jets of a plurality of jets1150shown inFIG. 12can be actively controlled to complement the controlling of arcuate-shaped vanes1220. It is conceivable that only the plurality of jets1150(and not the plurality of vanes1220) be used to dynamically modify the airflow behind the carrier aircraft. Also, it is conceivable that only the plurality of vanes1220(and not the plurality of jets1150) be used to dynamically modify the airflow behind the carrier aircraft.

Referring toFIG. 13, an elevational view similar to the perspective view ofFIG. 12shows each vane of the plurality of controllable, radial-shaped vanes1320in a closed position in accordance with another embodiment. Each vane of the plurality of radial-shaped vanes1320is disposed in circular-shaped frame1310.

Controllable compressed air jets, such as described hereinabove with reference to other embodiments, can be used in the embodiment ofFIG. 13. For example, jets of a plurality of jets1350shown inFIG. 13can be actively controlled to complement the controlling of radial-shaped vanes1320. It is conceivable that only the plurality of jets1350(and not the plurality of vanes1320) be used to dynamically modify the airflow behind the carrier aircraft. Also, it is conceivable that only the plurality of vanes1320(and not the plurality of jets1350) be used to dynamically modify the airflow behind the carrier aircraft.

Although the above description described using arcuate-shaped vanes1220(FIGS. 11 and 12) or radial-shaped vanes1320(FIG. 13), it is conceivable that any combination of arcuate-shaped vanes or radial-shaped vanes may be used together.

Referring toFIG. 14, flow diagram1400depicts an example method of dynamically controlling airflow behind a carrier aircraft in accordance with an embodiment. In block1410, each vane of a plurality of vanes is controlled between an opened position and a closed position to dynamically modify the airflow behind the carrier aircraft during an in-flight recovery of a UAV. In block1420, alternatively, or in addition to, each jet of a plurality of compressed air jets is controlled to provide active airflow to dynamically modify the airflow behind the carrier aircraft during the in-flight recovery of the UAV. In block1430, optionally, each door of a plurality of doors is controlled between an opened position and a closed position to dynamically modify the airflow behind the carrier aircraft during the in-flight recovery of the UAV.

Referring toFIG. 15A, a schematic view of an example airflow control apparatus1500including a first layer1510of controllable vanes and a second layer1520of controllable vanes (i.e., stacked layers) in accordance with an embodiment is illustrated. For simplicity, vanes of the first and second layers1510,1520of controllable vanes are schematically shown inFIG. 15Aas sticks, and other components such as a frame are omitted.

Vanes of first layer1510of controllable vanes and vanes of second layer1520of controllable vanes are perpendicular to each other. As shown inFIG. 15A, some vanes of first layer1510are rotatable in the clockwise direction, and some vanes of first layer1510are rotatable in the counter-clockwise direction. Similarly, some vanes of second layer1520are rotatable in the clockwise direction, and some vanes of second layer1520are rotatable in the counter-clockwise direction.

InFIG. 15A, the incoming freestream flow direction is perpendicular to the plane in which vanes of the first layer1510and vanes of the second layer1520lie. In this particular example, vanes of first layer1510of controllable vanes control airflow in side-to-side directions, and vanes of second layer1520of controllable vanes control airflow in up-and-down directions. However, it is conceivable that the incoming freestream flow direction may be from any direction relative to the plane in which vanes of the first and second layers1510,1520lie. For simplicity, the incoming freestream flow direction that is perpendicular to the plane in which vanes of the first and second layers1510,1520is described herein.

Vanes of first layer1510includes center vanes1512, and vanes of second layer1512include center vanes1522. Structure and operation of center vanes1512of first layer1510and center vanes1522of second layer1520are the same. For simplicity, structure and operation of only center vanes1512of first layer1510are discussed herein.

ReferringFIG. 15B, a schematic view of center vanes1512of first layer1510shown inFIG. 15A, looking approximately in the direction of arrow “15B” shown inFIG. 15A, is illustrated. Center vanes1512include first vane1514pivotable about first hinge1515that can be anchored to a frame (not shown). Center vanes1512also include second vane1516pivotable about second hinge1517that can be anchored to the frame.

As shown inFIG. 15B, each of first vane1514and second vane1516is in a fully opened position. Each of first and second vanes1514,1516lie in a plane parallel to the incoming freestream flow direction. First vane1514is pivotable counter-clockwise about first hinge1515from its fully opened position shown inFIG. 15Bto a fully closed position. Similarly, second vane1516is pivotable clockwise about second hinge1517from its fully opened position shown inFIG. 15Bto a fully closed position.

Referring toFIG. 15C, a schematic view similar to the schematic view ofFIG. 15B, and showing each of first and second vanes1514,1516in a different position. More specifically, first vane1514is rotated counter-clockwise to a partially opened position to deflect the incoming free-streaming flow to the left (as viewed looking atFIG. 15C). Similarly, second vane1516is rotated clockwise to a partially opened position to deflect the incoming free-streaming flow to the right.

It should also be apparent that an array of controlled louvers and wing-type flaps are provided to generate a managed field of airflow behind a leading aircraft. Alternatively, or in addition to, an array of controlled compressed air jets is provided to generate a managed field of airflow behind a leading aircraft. The field of airflow is dynamically controlled to selectively create a flow bubble that eases a trailing aircraft to be recovered by the leading aircraft into a specific position or onto a recovery carriage.

It should also be apparent that the dynamically adjustable field of airflow behind the leading aircraft provides more predictable and more stable operations of the trailing aircraft as required during an in-flight recovery of the trailing vehicle. The ability to dynamically control a field of airflow behind the leading aircraft alleviates unpredictable behaviors, especially in the presence of external turbulence caused by the leading aircraft, weather, and other effects.

Aspects of disclosed embodiments may be implemented in software, hardware, firmware, or a combination thereof. The various elements of the system, either individually or in combination, may be implemented as a computer program product tangibly embodied in a machine-readable storage device for execution by a processor. Various steps of embodiments may be performed by a computer processor executing a program tangibly embodied on a computer-readable medium to perform functions by operating on input and generating output. The computer-readable medium may be, for example, a memory, a transportable medium such as a compact disk or a flash drive, such that a computer program embodying aspects of the disclosed embodiments can be loaded onto a computer.

Although various aspects of disclosed embodiments have been shown and described, modifications may occur to those skilled in the art upon reading the specification. The present application includes such modifications and is limited only by the scope of the claims.