Patent Description:
In recent years, unmanned aerial vehicles (UAVs) or drones have been used to fly significant distances to transport payloads (e.g., packages, supplies, equipment, etc.) or gather information. Some UAVs land on runways while others are captured in flight by UAV recovery systems. Capturing UAVs without the use of a runway enables greater flexibility in recovery locations. In particular, a UAV can be recovered in an unprepared area or on relatively smaller ships or other vessels or vehicles.

<CIT> states, according to its abstract, a method of launching and retrieving a UAV (Unmanned Aerial Vehicle). The preferred method of launch involves carrying the UAV up to altitude using a parasail similar to that used to carry tourists aloft. The UAV is dropped and picks up enough airspeed in the dive to perform a pull-up into level controlled flight. The preferred method of recovery is for the UAV to fly into and latch onto the parasail tow line or cables hanging off the tow line and then be winched back down to the boat.

<CIT> states, according to its abstract, a parachute arrangement comprising a parachute having a canopy, a plurality of shroud lines coupled to the canopy, and a plurality of connectors coupled to the shroud lines for attachment to a load; and a packaging for the parachute, the packaging comprising an enclosure formed of a web material, wherein each of the shroud lines and/or connectors is engaged with the enclosure to thereby maintain the connectors in a spaced-apart arrangement for attachment to the load.

<CIT> states, according to its abstract, launch and/or recovery for unmanned aircraft and/or other payloads, including via parachute-assist, and associated systems and methods are disclosed. A representative method for lofting a payload includes directing a lifting device upward, releasing a parachute from the lifting device, with the parachute carrying a pulley and having a flexible line passing around the pulley. The flexible line is connected between a tension device (e.g., a winch) and the payload. The method further includes activating the tension device to reel in the flexible line and accelerate the payload upwardly.

<CIT> states, according to its abstract, an apparatus for launch and recovery of an Unmanned Aerial Vehicle (UAV), a method for launching a UAV, a method for recovering a UAV and a kit of parts for launch and recovery of a UAV. The apparatus comprises a boom having a center member for receiving the UAV, and first and second arm members extending outwardly and upwardly from the center member, wherein the boom is configured to be lifted to a predetermined height into the air from a reference point; and wherein the boom is movable in the air to an operating position forward of the reference point.

<CIT> states, according to its abstract, an asymmetric aircraft and an aircraft that can operate from small ships and be stored in high density with three aircraft or more in one helicopter hangar without needing a landing gear or wing fold. These aircraft slide into and out of the hangar on dollies like circuit boards in a computer and are launched and recovered using a large towed parafoil.

<CIT> states, according to its abstract, methods and apparatus to recover unmanned aerial vehicles (UAVs) with kites are disclosed. A disclosed example apparatus to recover a UAV during flight includes a tether line, a tensioner operatively coupled to the tether line, and a kite operatively coupled to the tether line to support the tether line for recovery of the UAV.

An aspect includes an apparatus to recover an aircraft according to independent claim <NUM>.

A second aspect includes a method to recover an aircraft according to independent claim <NUM>.

The figures are not to scale. Instead, the thickness of the layers or regions may be enlarged in the drawings. In general, the same reference numbers will be used throughout the drawing(s) and accompanying written description to refer to the same or like parts. As used herein, unless otherwise stated, the term "above" describes the relationship of two parts relative to Earth. A first part is above a second part, if the second part has at least one part between Earth and the first part. Likewise, as used herein, a first part is "below" a second part when the first part is closer to the Earth than the second part. As noted above, a first part can be above or below a second part with one or more of: other parts therebetween, without other parts therebetween, with the first and second parts touching, or without the first and second parts being in direct contact with one another. As used in this patent, stating that any part is in any way on (e.g., positioned on, located on, disposed on, or formed on, etc.) another part, indicates that the referenced part is either in contact with the other part, or that the referenced part is above the other part with one or more intermediate part(s) located therebetween. As used herein, connection references (e.g., attached, coupled, connected, and joined) may include intermediate members between the elements referenced by the connection reference and/or relative movement between those elements unless otherwise indicated. As such, connection references do not necessarily infer that two elements are directly connected and/or in fixed relation to each other. As used herein, stating that any part is in "contact" with another part is defined to mean that there is no intermediate part between the two parts.

Unless specifically stated otherwise, descriptors such as "first," "second," "third," etc. are used herein without imputing or otherwise indicating any meaning of priority, physical order, arrangement in a list, and/or ordering in any way, but are merely used as labels and/or arbitrary names to distinguish elements for ease of understanding the disclosed examples. " In such instances, it should be understood that such descriptors are used merely for identifying those elements distinctly that might, for example, otherwise share a same name. As used herein, "approximately" and "about" refer to dimensions that may not be exact due to manufacturing tolerances and/or other real world imperfections.

Methods and apparatus to recover unmanned aerial vehicles (UAVs) with kites are disclosed. Some UAVs are recovered by recovery systems, which employ a recovery tether line that is suspended vertically. In particular, a UAV contacts and/or impacts the tether line and, as a result, the UAV is decelerated and/or stopped from flight, thereby enabling recovery of the UAV without need for a runway. In some known implementations, a parachute or support beam or movable boom is used to suspend the tether line for recovery of the UAV.

Examples disclosed herein enable an effective and relatively low cost recovery of an aircraft (e.g., a UAV) via a stationary platform or a moving vehicle or vessel (e.g., a ship, etc.). According to examples disclosed herein, multiple parafoils (e.g., parafoil kites) extend from a boat or a stationary platform. In particular, a kite generates lift to support and/or suspend a tether line carried by a vessel while a parafoil operatively coupled to the tether line is deployed, thereby enabling controlled deceleration of the aircraft. In other words, the kite supports and/or suspends the tether line while the parafoil decelerates the aircraft. The parafoil can be implemented as a kite, parasail or parachute, for example. Further, the aforementioned tether line can be operatively coupled to a tension device (e.g., a tensioner, a winch, a motorized winch, etc.). The tension device is implemented to retrieve the tether line along with the kite and the aircraft.

According to examples disclosed herein, the kite supports the tether line and the parafoil is deployed and/or launched from the tether line in response to the aircraft contacting and/or impacting the tether line. For example, an impact of a wing (e.g., a distal portion of a wing) with the tether line causes a release to launch/deploy the parafoil away from the tether line. In turn, the parafoil expands and/or unfolds as it is deployed from the tether line. In some examples, the parafoil is propelled and/or pushed away from the tether line. The release can include at least a frangible portion (e.g., a breakable section, a portion prone to fracturing) that breaks (e.g., fractures, bends, etc.) when the wing impacts and/or pulls on the tether line.

In some examples, a tensioner is operatively coupled to the tether line and/or the release. In some examples, the release includes and/or is operatively coupled to a bag utilized to enclose and/or restrain the parafoil when the parafoil is folded and stowed. In some examples, the bag is moved away from and/or slid away from the parafoil upon movement of the tether line and/or impact of the aircraft with the tether line. In some examples, a spring or other energy storage device is implemented to propel and/or launch the parafoil away from the tether line in response to the aircraft contacting the tether line. A shape of the kite is altered and/or changed in response to the aircraft contacting the tether line and/or the parafoil being deployed. The kite is converted to a trailing edge drag device.

As used herein, the term "parafoil" refers to a nonrigid airfoil flight structure. Accordingly, the term "parafoil" can refer to a kite, a parachute, a parasail, a glider, any similar type of flight structure to the aforementioned examples, or a combination of any similar type of flight structures. <FIG> depicts a UAV recovery system <NUM> in accordance with teachings of this disclosure. The UAV recovery system <NUM> of the illustrated example is implemented on a vessel <NUM> and includes a tether line control mount <NUM>, which includes a boom (e.g., a lower tether boom, a rotatable boom, a swivel boom, a pivoting boom, etc.) <NUM> and boom supports <NUM>. In the illustrated example, a tether line <NUM> extends from the tether line control mount <NUM> while a tensioner or tension device <NUM>, which is implemented as a winch in this example, is operatively coupled to the tether line <NUM>. Further, the tether line <NUM> is operatively coupled to a kite (e.g., a parafoil kite, a drogue kite, a first kite, etc.) <NUM> having support lines (e.g., kite lines, foil lines, etc.) <NUM> and a foil (e.g., a lift foil, a lift generation foil, a kite body) <NUM>. The UAV recovery system <NUM> of the illustrated example is implemented to capture an aircraft <NUM>, which is a UAV in this example. In other examples, the aircraft <NUM> may be implemented as another type of aircraft (e.g., a manned aircraft), spacecraft, etc..

The example UAV <NUM> includes a fuselage <NUM>, wings <NUM> each of which includes a distal capture portion <NUM>, and a propulsion system <NUM> with propellers <NUM>. In this example, the distal capture portion <NUM> extends from at least one of the corresponding wings <NUM> generally along a direction of movement of the UAV <NUM>. However, any appropriate type of capture or recovery mechanism can, instead, be implemented on any other portion and/or component (e.g., the fuselage <NUM>) of the UAV <NUM>. Further, any other appropriate type of propulsion of the UAV <NUM> can instead be implemented.

In the illustrated example of <FIG>, the UAV recovery system <NUM> includes a parafoil (e.g., a second auxiliary kite, a second kite, a parasail, a parachute, etc.) <NUM>, which is depicted as stored/stowed onto the tether line <NUM>. As will be described below in connection with <FIG>, the parafoil <NUM> is deployable from the tether line <NUM> and/or a release component or device operatively coupled to the tether line <NUM> when the UAV <NUM> contacts and/or impacts the tether line <NUM>. In this example, the parafoil <NUM> is placed in an inline arrangement such that the parafoil <NUM> is positioned on the tether line <NUM> between the boom <NUM> and the kite <NUM>.

To recover and/or capture the UAV <NUM> as the UAV <NUM> moves along a flight path <NUM>, one of the distal capture portions <NUM> is brought into contact with the tether line <NUM>. As a result, the parafoil <NUM> is deployed to decelerate and or control movement of the UAV <NUM>. In turn, the UAV <NUM> is brought to a rest and remains attached to the tether line <NUM>. In this example, the tether line <NUM> is suspended by the kite <NUM> as the kite <NUM> generates lift to support the tether line <NUM> in the air (e.g., substantially vertically in the air, within <NUM> degrees from vertical). However, subsequent to decelerating the UAV <NUM> by deploying the parafoil <NUM>, a shape and/or overall geometry of the kite <NUM> is changed (e.g., the kite <NUM> changes shape to transition to a trailing edge drag device). For example, the parafoil <NUM> may pull on at least a portion of the kite <NUM> to change a shape of the kite <NUM> while the parafoil <NUM> is deployed.

In some examples, the tensioner <NUM> maintains a tension of the tether line <NUM> extending between the tether line control mount <NUM> and the kite <NUM> within a threshold range and/or at a nominal tension value (e.g., to facilitate capture of the UAV <NUM> and/or release of the parafoil <NUM>). In some examples, the kite <NUM> is steered to direct the tether line <NUM> within a requisite range of the aforementioned flight path <NUM> for deployment of the parafoil <NUM> during capture of the UAV <NUM>. Additionally or alternatively, the kite <NUM> is directed toward to the flight path <NUM> based on a desired impact force of the tether line <NUM> with the distal capture portion <NUM>. In some examples, a degree to which the parafoil <NUM> is expanded and/or deployed varies with a degree of impact force of the UAV <NUM> with the tether line <NUM>. In some other examples, the kite <NUM> is coupled to and/or extends from the parafoil <NUM> instead of the tether line <NUM>. In some examples, a steering device <NUM> is implemented to direct lateral and/or translation movement of the tether line control mount <NUM> and/or the kite <NUM>.

While the example of <FIG> is shown in the context of the vessel <NUM>, examples disclosed herein can be applied to any stationary or moving support structure (e.g., a vehicle).

<FIG> depict an example recovery sequence not covered by the scope of the appended claims. <FIG> depicts the UAV <NUM> approaching the tether line <NUM>, which extends between the vessel <NUM> and the kite <NUM>. In this example, the kite <NUM> is supporting the tether line <NUM> as the UAV <NUM> is being controlled and/or navigated to cause the distal capture portion <NUM> (shown in <FIG>) of the UAV <NUM> to contact the tether line <NUM> and, thus, decelerate the UAV <NUM>. In this example, the parafoil <NUM> remains undeployed and positioned on the tether line <NUM> proximate the kite <NUM>. Particularly, the example parafoil <NUM> remains stowed and unfolded prior to being deployed.

Turning to <FIG>, the UAV <NUM> is shown in contact with the tether line <NUM>. In this example, the distal capture portion <NUM> shown in <FIG> is caught on the tether line <NUM>, thereby causing the parafoil <NUM> to deploy from the tether line <NUM>. As a result, an amount of force translated to the UAV <NUM> is reduced. In this example, the parafoil <NUM> is unfolded and/or expanded during the deployment thereof, thereby decelerating the UAV <NUM>. In this example, the kite <NUM> is smaller than the parafoil <NUM>. However, in other examples, the kite <NUM> is larger than the parafoil <NUM>.

<FIG> depicts the UAV <NUM> captured on the tether line <NUM> and being winched toward the vessel <NUM>. In this particular example, the tension device <NUM> shown in <FIG> causes a motion (e.g., a reeling motion) of the tether line <NUM> and the UAV <NUM> toward the vessel <NUM> while at least one of the kite <NUM> and the parafoil <NUM> maintains a lift force (e.g., an upward lift force in the view of <FIG>) to support the tether line <NUM>. As a result, the UAV <NUM> is brought onto the vessel <NUM>. <FIG> depict another example recovery sequence not covered by the scope of the appended claims. The example recovery sequence of <FIG> is similar to the example recovery sequence shown in <FIG>, but depicts a different kite configuration. Turning to <FIG>, a kite <NUM> is shown supporting the tether line <NUM> and a parafoil <NUM>. In this particular example, the kite <NUM> is configured as a frame or diamond kite and the parafoil <NUM>, which is implemented as a parafoil kite in this example, is positioned on the tether line <NUM> between the kite <NUM> and a structure holding the tether line <NUM>, such as the vessel <NUM> of <FIG>.

As can be seen in the illustrated example of <FIG>, the UAV <NUM> is depicted impacting the tether line <NUM>. As a result of the impact between the UAV <NUM> and the tether line <NUM>, the parafoil <NUM> begins to expand and deploy, thereby causing the kite <NUM> to move to a higher altitude from the ground/sea. In other words, the deployment of the kite <NUM> from the tether line <NUM> extends an effective distance from the kite <NUM> to the ground/sea. Additionally or alternatively, the kite <NUM> is coupled to the parafoil <NUM> instead of the tether line <NUM>.

Turning to <FIG>, the parafoil <NUM> is depicted as fully deployed. In this example, the kite <NUM> continues to provide lift for the parafoil <NUM> as the UAV <NUM> is decelerated. In this example, the kite <NUM> also supports the tether line <NUM> and the UAV <NUM> while the tether line <NUM> is drawn in to recover the UAV <NUM> (e.g., at the vessel <NUM>, at a ground-based station, etc.).

<FIG> depict yet another example recovery sequence according to the invention defined in the appended claims. Turning to <FIG>, a kite <NUM>, which is implemented as a parafoil kite or a sled kite for example, is shown supporting a parafoil <NUM> stowed on the tether line <NUM> in a bag (e.g., a parachute bag) <NUM>. In this example, the parafoil <NUM> is folded while being stowed on the tether line <NUM>.

<FIG> depicts the UAV <NUM> impacting the tether line <NUM> and causing the parafoil <NUM> to deploy to control a deceleration of the UAV <NUM> during recovery thereof. In some examples, the kite <NUM> also plays a role in decelerating the UAV <NUM> subsequent to impact of the UAV <NUM> with the tether line <NUM>. In this example, the kite <NUM> extends from a portion of the parafoil <NUM> when the parafoil <NUM> is deployed. In other words, the kite <NUM> can be coupled to and/or attached to at least a portion of the parafoil <NUM>.

Turning to <FIG>, the parafoil <NUM> is shown fully deployed. The kite <NUM> changes shape to become a trailing edge drag device of the parafoil <NUM> when the parafoil <NUM> is deployed. The kite <NUM> is folded, reshaped and or altered to a trailing edge drag device shape upon impact of the UAV <NUM> with the tether line <NUM>. In some such examples, folding of the kite <NUM> can result from the release of the parafoil <NUM> from the tether line <NUM> and/or a change in tension of the tether line <NUM>.

<FIG> depicts an example kite release system <NUM> not covered by the scope of the appended claims.

In the illustrated example of <FIG>, a kite <NUM> supports the tether line <NUM> and is implemented as a tube kite. In the illustrated example of <FIG>, a release assembly <NUM> is implemented to deploy a parafoil <NUM> from the tether line <NUM>. As will be discussed in greater detail below in connection with <FIG>, the release assembly <NUM> causes deployment of the parafoil <NUM> in response to impact of the UAV <NUM> with the tether line <NUM>.

<FIG> is a detailed view of a portion of an example kite release system <NUM> according to the invention defined in the appended claims. According to the illustrated example, the release assembly <NUM> is shown extending between an upper portion 601a and a lower portion 601b of the tether line <NUM>. The example release assembly <NUM> includes a release device (e.g., a release tension device, a frangible release device, a spring-loaded release, etc.) <NUM> that is positioned between the upper portion 601a and a coiled portion <NUM> of the tether line <NUM>. In this example, the coiled portion <NUM> extends between the release device <NUM> and the upper portion 601b of the tether line <NUM>. In other examples, the coiled portion <NUM> is not part of the tether line <NUM>. In some examples, the parafoil <NUM> is stowed, captivated and/or stored in a bag <NUM>. In some examples, a spring or energy-storage device <NUM> is implemented.

To release and deploy the parafoil <NUM> when the UAV <NUM> impacts the tether line <NUM>, an increase in tension (e.g., a rapid increase in tension) of the tether line <NUM> causes the release device <NUM> to open (e.g., break, unlock, etc.) and, in turn, enables the coiled portion <NUM> to uncoil and/or expand, thereby enabling the kite <NUM> of <FIG> to move away from the parafoil <NUM>. As a result, the parafoil <NUM> is unfolded and deployed from the tether line <NUM>. In this example, air flowing proximate to the parafoil <NUM> facilitates expansion and/or unfolding of the parafoil <NUM>. Additionally or alternatively, movement and/or displacement of the bag <NUM> away from the parafoil <NUM> causes the parafoil <NUM> to expand, unfold and/or deploy. In some examples, the bag <NUM> is torn as the parafoil <NUM> is deployed (e.g., the bag <NUM> is frangible). Additionally or alternatively, the bag <NUM> and/or an opening of the bag <NUM> is widened when the parafoil <NUM> is being deployed to facilitate removal of the parafoil <NUM> therefrom. In some examples, the bag <NUM> is torn in response to the UAV <NUM> contacting the tether line <NUM>.

In some examples, the release device <NUM> is frangible. For example, the release device <NUM> can break and/or fracture when a tension and/or force of the tether line <NUM> exceeds a threshold (e.g., a threshold force value). In some such examples, the release device <NUM> can be generally ringshaped (e.g., an annular ring shape), for example, such that at least a portion of its ring-shape geometry can fracture when tension of the tether line <NUM> exceeds the threshold in response to the UAV <NUM> impacting the tether line <NUM>. In some examples, movement of the tether line <NUM> (e.g., movement of the lower portion 601b) causes the bag <NUM> to separate from (e.g., slide off, slip off, uncover, etc.) the parafoil <NUM>. In some examples, the spring or energy-storage device <NUM> is implemented to propel and/or launch the parafoil <NUM> away from the tether line <NUM> and/or the bag <NUM> in response to the UAV <NUM> contacting the tether line <NUM>. In some examples, the tether line <NUM> and/or the coiled portion <NUM> is coupled to a bridle associated with the parafoil <NUM>.

Any of the example features and/or aspects described above in connection with <FIG> can be combined or implemented separately. In other words, the examples of <FIG> are not limiting and any aspect and/or feature of any of the examples can be utilized in combination with another aspect and/or feature. Modifications or changes may be made without departing from the invention to which this European patent relates, which is defined by the appended claims.

<FIG> is a flowchart representative of an example method <NUM> to implement the example UAV recovery system <NUM> according to the invention defined in the appended claims. The example method <NUM> begins as a kite (e.g., the kite <NUM>, the kite <NUM>, the kite <NUM>, the kite <NUM>) is about to be deployed and/or launched to support the tether line <NUM> from a ground-based station and/or vehicle (e.g., a land-based vehicle, a watercraft, submersible, an aircraft, a spacecraft, etc.). A parafoil (e.g., the parafoil <NUM>, the parafoil <NUM>, the parafoil <NUM>, the parafoil <NUM>) is currently stowed and folded in a compartment or other storage device (e.g., the bag <NUM>) associated with the tether line <NUM>.

At block <NUM>, the kite is deployed to suspend the tether line <NUM>. In this example, the kite is caused to hover and/or be suspended in the air at a desired height for recovery of the UAV <NUM> (e.g., a recovery flying altitude of the UAV <NUM>, a height in which the UAV <NUM> can be recovered without significant loading and/or forces, etc.).

At block <NUM>, in some examples, it is determined if a tension of the tether line <NUM> is within a threshold range or value. The threshold range or value can correspond to a release, a breakage or fracture value associated with the release device <NUM>. For example, if the tension of the tether line <NUM> is within the threshold (block <NUM>), control of the process proceeds to block <NUM>. Otherwise, the process proceeds to block <NUM>.

At block <NUM>, the tension of the tether line <NUM> is adjusted by the tension device <NUM>. In some examples, the tension of the tether line <NUM> is adjusted to an amount of tension corresponding to a working range (e.g., operating range) of the release assembly <NUM> and/or the release device <NUM>. For example, the tension of the tether line <NUM> can be adjusted so that the UAV <NUM> impacting the tether line <NUM> can release and/or cause intended breakage of the release device <NUM>.

At block <NUM>, the UAV <NUM> is caused to impact and/or contact the tether line <NUM>. In this example, the UAV <NUM> is directed to fly toward the tether line <NUM> so that at least a portion of the UAV <NUM> contacts and is captured by the tether line <NUM>. In some examples, the UAV <NUM> is controlled to impact the tether line <NUM> at a defined speed range.

At block <NUM>, the parafoil is deployed from the tether line <NUM> in response to the UAV <NUM> contacting/impacting the tether line <NUM>. In some examples, the parafoil is deployed from the kite. In the illustrated example, the parafoil is deployed to facilitate deceleration of the UAV <NUM> in a controlled manner. In some examples, the unfolding and/or expansion of the parafoil also facilitates deceleration of the UAV <NUM>.

At block <NUM>, the UAV <NUM> is drawn via the tether line <NUM>. In this example, the UAV <NUM> is drawn toward the vessel <NUM> for recovery of the UAV <NUM>. In other examples, the UAV <NUM> is drawn toward a stationary ground-based structure on land.

At block <NUM>, it is determined whether to repeat the process. If the process is to be repeated (block <NUM>), control of the process proceeds to block <NUM>. Otherwise, the process ends. This determination may be based on whether additional aircraft is to be recovered.

From the foregoing, it will be appreciated that example methods, apparatus and articles of manufacture have been disclosed that enable cost-effective, controlled and operator-friendly recovery of aircraft. Further, examples disclosed herein can be implemented to reduce impact and/or loading encountered by the aircraft during recovery thereof. As a result, examples disclosed herein can enable aircraft that are relatively light weight and, in turn, fuel efficient and/or low cost.

Although certain example methods, apparatus and articles of manufacture have been disclosed herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus and articles of manufacture falling within the scope of the claims of this patent. While examples disclosed herein are shown and described in the context of UAVs, examples disclosed herein can be applied to any appropriate type of aircraft.

Claim 1:
An apparatus (<NUM>) to recover an aircraft (<NUM>), the apparatus (<NUM>) comprising a kite (<NUM>, <NUM>);
a tether line (<NUM>) to be supported by the kite (<NUM>, <NUM>) at a distal end thereof; and
a parafoil (<NUM>, <NUM>), the tether line carrying the parafoil;
a release device (<NUM>) configured to deploy the parafoil (<NUM>, <NUM>) from the tether line (<NUM>) in response to the aircraft (<NUM>) contacting the tether line (<NUM>),
wherein the kite (<NUM>, <NUM>) is configured to change its shape to a trailing edge drag device in response to the parafoil (<NUM>, <NUM>) being deployed.