System and Method for Unmanned Aerial Vehicle-Enabled Delivery of Cargo Without Human Intervention

Abstract

An unmanned cargo loading and transport system adapted for operation with an unmanned aerial vehicle (UAV) comprising a payload pad comprising a plurality of support members movable from an extended mode to a retracted mode when exposed to a lateral force applied to the support members and a payload container adapted to attach to a UAV and pick up cargo from the payload pad by transferring the weight of the cargo from the payload pad to the payload container. The lower portion of the payload container comprises two generally opposed cargo doors movably mounted at opposed sides and movable inwardly to a closed position and outwardly to an open position to receive cargo when the payload container is positioned at the payload pad. The system further comprises a motive power mechanism coupled to the cargo doors for selectively moving the doors between their open and their closed positions.

Claims

1. An unmanned cargo loading and transport system adapted for operation with an unmanned aerial vehicle (UAV) the system comprising: a payload pad presenting a generally horizontal upper plane for supporting cargo when the pad is positioned on a generally horizontal substrate supporting the pad, the payload pad further comprising a plurality of support members together defining at upper ends thereof an upper plane of the payload pad, each of the support members having a vertically extended mode for supporting weight imposed downward on the support member and a retracted mode in which the support member is of shorter vertical length than the support members in the vertically extended mode, the support members being movable from the extended mode to the retracted mode when exposed to a lateral force applied to the support member; a payload container comprising: an upper portion adapted to attach to a UAV; a plurality of side portions coupled to the upper portion and extending downward from the upper portion; and a lower portion that together with the upper portion and side portions defines an enclosure for holding cargo in the payload container, the payload container further adapted to pick up the cargo from the payload pad by transferring the weight of the cargo from the payload pad to the payload container and hold the cargo within the payload container while in transit by a UAV, and wherein a lower portion of the payload container comprises two generally opposed cargo doors movably mounted at opposed sides of the side portions of the payload container and movable inwardly to a closed position such that opposed edges of the cargo doors are substantially adjacent to present a generally closed bottom of the payload container, the cargo doors further movable outwardly to an open position at which the opposed edges of the cargo doors are distal from one another to present an open bottom of the payload container for receiving cargo when the payload container is positioned at the payload pad; and a motive power mechanism coupled to the cargo doors for selectively moving the doors between their open and their closed positions.

2. The system of claim 1, wherein one or more of the support members comprise bristles that are naturally biased to the vertically extended mode.

3. The system of claim 1, wherein the payload pad further comprises a landing aid adapted to be sensed by one or more sensors on the UAV for guiding the UAV to a desired location and orientation on the payload pad.

4. The system of claim 1, wherein one or more of the support members comprise a series of rollers carried on generally vertically extending links mounted on the payload pad for pivotal movement about horizontally extending axes that are substantially parallel to the opposed edges of the cargo doors.

5. The system of claim 3, wherein the landing aid comprises a transmitter for transmitting signals to the one or more sensors on the UAV.

6. An unmanned cargo loading and transport system adapted for operation with an unmanned aerial vehicle (UAV), the system comprising: a payload pad presenting a substantially horizontal upper plane for supporting cargo when the payload pad is positioned on a substantially horizontal substrate supporting the payload pad, the payload pad comprising a bed of deformable elastomeric material; a payload container comprising: an upper portion adapted to be attached to a UAV; a plurality of side portions coupled to the upper portion and extending downward from the upper portion; and a lower portion that together with the upper and side portions defines an enclosure for holding cargo in the payload container, the payload container adapted to pick up the cargo from the payload pad by transferring a weight of the cargo from the payload pad to the payload container and holding the cargo within the payload container while in transit by a UAV, and wherein a lower portion of the payload container comprises two generally opposed cargo doors movably mounted at opposed sides of the side portions of the payload container and movable inwardly to a closed position such that opposed edges of the cargo doors are substantially adjacent to present a generally closed bottom of the payload container, the cargo doors further movable outwardly to an open position at which the opposed edges of the cargo doors are distal from one another to present an open bottom of the payload container for receiving cargo when the payload container is positioned at the payload pad; and a motive power mechanism coupled to the cargo doors for selectively moving the doors between their open and their closed positions.

7. The system of claim 6, wherein the deformable elastomeric material comprises an elastomeric foam material.

8. The system of claim 7, wherein the payload pad comprises two beds of deformable elastomeric material positioned in an end-to-end configuration and separated by a substantially vertically-extending partition member.

9. The system of claim 8, wherein the substantially vertially-extending partition member is substantially a same vertical height as a vertical height of the two beds of deformable elastomeric material.

10. The system of claim 6, wherein the payload pad further comprises a landing aid adapted to be sensed by one of more sensors on the UAV for guiding the UAV to a desired location and orientation on the payload pad.

11. The system of claim 10, wherein the landing aid comprises a transmitter for transmitting signals to the one or more sensors on the UAV.

12. A payload container adapted for use in an unmanned aerial vehicle (UAV) cargo transport system, with the payload container being adapted to selectively engage, hold and release cargo to be transported by the UAV, the payload container comprising: an upper portion having a connector for attaching the payload container to a UAV, a plurality of side portions extending downward from the upper portion; and a lower portion that together with the upper and side portions defines an enclosure for holding cargo in the payload container, the lower portion comprising two generally opposed cargo doors movably mounted at opposed sides of the side portions of the payload container and movable inwardly to a closed position such that opposed edges of the cargo doors are substantially adjacent to present a generally closed bottom of the payload container that substantially closes the lower portion of the payload container, the cargo doors further movable outwardly to an open position at which the opposed edges of the cargo doors are distal from one another to present an open bottom of the payload container for at least a substantial portion of the lower portion of the payload containter for receiving cargo when the payload container is positioned above cargo to be transported; and a motive power mechanism coupled to the cargo doors for selectively moving the doors between their open and their closed positions for opening and closing the lower portion of the payload container.

13. The payload container of claim 12, wherein the payload container further comprises a linkage for coupling the cargo doors to the payload container for pivotal and translational movement between the open positon and the closed position.

14. The payload container of claim 13, wherein the motive power mechanism is configured to move the payload container cargo doors between the open position and the closed position via the linkage.

15. The payload container of claim 12, wherein an upper surface of the payload container cargo doors is comprised of a material having a coefficient of friction less than about 0.2.

16. The payload container of claim 12, wherein the side portions of the payload container are formed of planar members comprising at least one of a metal and a plastic.

17. The payload container of claim 13, wherein the linkage comprises a four-bar linkage mechanism.

18. The payload container of claim 12, wherein the cargo doors comprise a sheet of a material having a coefficient of friction that is less than or equal to about 0.2 on the upper surface of the cargo doors.

19. The payload container of claim 12, wherein the payload container further comprises a battery for storing electrical power on board the payload container.

20. The payload container of claim 12, wherein the payload container further comprises a camera system for imaging cargo held in the payload container.

21. The payload container of claim 12, wherein the payload container further comprises a temperature sensor, transfer ports in the payload container for transferring air into and out of the payload container and a fan operatively associated with the temperature sensor, the transfer ports and fan configured to move air from outside the payload container through the payload container to regulate an interior temperature of the payload container.

22. The payload container of claim 12, wherein the payload container further comprises an air bladder system for holding cargo in place in the payload container during transport.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0028] A more complete understanding of the present invention may be derived by referring to the detailed description when considered in connection with the following illustrative figures. In the figures, like reference numbers refer to like elements or acts throughout the figures.

[0029] FIG. 1 provides a perspective view of a payload container detached from an unmanned aerial vehicle.

[0030] FIG. 2 provides an isometric view of a side of the payload container with the protective panel removed. This view presents an embodiment of the cargo door attachment and movement mechanisms, including the electric motor, worm drive, and propulsion linkages.

[0031] FIG. 3 provides an isometric view of the side of the payload container with the protective panel removed. This view presents an embodiment of the payload container cargo doors shown in an opened position and an embodiment of the payload pad shown in relation to the payload container.

[0032] FIG. 4 provides an isometric view of a side of the payload container with the protective panel removed. This view presents an embodiment of the payload container cargo doors shown in the process of lifting the cargo from the payload pad. This view further presents the interaction of the payload container cargo doors with the payload pad.

[0033] FIG. 5 provides an isometric view of a side of the payload container with the protective panel removed. This view presents exemplary detail of an embodiment of the payload container cargo door where the cargo door is covered with a material having a low coefficient of friction and the cargo door is further equipped with a low-friction sheet that enables the cargo to move along the door’s surface as the cargo door moves under the cargo.

[0034] FIG. 6 provides a detailed isometric view of an example of an interaction of the cargo and the payload container cargo doors, as presented in FIG. 5.

[0035] FIG. 7 provides an isometric view of an alternative embodiment of the payload container where the payload container comprises batteries.

[0036] FIG. 8 provides a perspective view of the payload pad. The view presented is an embodiment that includes cargo carrying bristles and UAV precision landing aids.

[0037] FIG. 9 provides an isometric top view of an embodiment of the payload pad.

[0038] FIG. 10 provides an isometric side view of an embodiment of the payload pad.

[0039] FIG. 11 provides an isometric view of a side of the payload container with the protective panel removed. This view presents a set of linkages used to modify the movement path of the cargo doors when opening and closing.

[0040] FIG. 12 provides an isometric view of a side of the payload container with the protective panel removed. This view presents another exemplary embodiment of the cargo door opening and closing mechanism.

[0041] FIG. 13 provides an isometric view of a side of the payload container with the protective panel removed. This view presents another embodiment of the cargo door opening and closing mechanism presented in FIG. 12 and illustrates the initial movement of the cargo door opening and closing processes.

[0042] FIG. 14 provides an isometric view of a side of the payload container with the protective panel removed. This view presents another embodiment of the cargo door opening and closing mechanism presented in FIG. 12 and illustrates the lateral movement phase of the cargo door opening and closing processes.

[0043] FIG. 15 provides an isometric view of a side of the payload container with the protective panel removed. This view presents another embodiment of the cargo door opening and closing mechanism presented in FIG. 12 and illustrates a scooping movement phase of the cargo door opening and closing processes.

[0044] FIG. 16 provides a perspective view of the payload container where only the cargo doors are shown, cargo is in position for loading by the payload container, and an alternative embodiment of the payload pad employs a roller assembly to support the cargo.

[0045] FIG. 17 provides an isometric view of the items presented in FIG. 16, with the payload container cargo doors shown in the initial phase of loading the cargo.

[0046] FIG. 18 provides an isometric view of the items presented in FIG. 16, with the payload container cargo doors shown in an interim phase of loading the cargo.

[0047] FIG. 19 provides an isometric view of the items presented in FIG. 16, with the payload container cargo doors shown in their position after cargo loading is completed.

[0048] FIG. 20 provides a perspective view of an interior of an embodiment of the payload container, which provides an image of a camera, smoke detector, and deflated cargo stabilization bladders.

[0049] FIG. 21 provides a perspective view of an interior of an embodiment of the payload container, which provides an image of inflated cargo stabilization bladders stabilizing cargo for flight.

[0050] FIG. 22 provides a perspective view of a typical UAV with a payload container attached that is shown positioned over a payload pad in the location and orientation used for the pickup or delivery of cargo.

[0051] FIG. 23 provides an isometric view of the payload container with the protective panel removed, positioned over an embodiment of the payload pad that utilizes a rigid element and foam pads to hold the cargo for loading or after unloading operations.

[0052] FIG. 24 provides an isometric view of the items presented in FIG. 23, with the payload container cargo doors shown during the closing motions and illustrates the deformation of the foam pads caused by the payload container cargo doors.

[0053] FIG. 25 provides an isometric of the items present in FIG. 23, where the payload container cargo doors have lifted the cargo from the foam pads and illustrates the clearance of the payload container cargo doors and the rigid element.

[0054] Elements and acts in the figures are illustrated for simplicity and have not necessarily been rendered according to any particular sequence or embodiment.

DETAILED DESCRIPTION

[0055] In the following description, and for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the various aspects of the invention. It will be understood, however, by those skilled in the relevant arts, that the present invention may be practiced without these specific details. In other instances, known structures and devices are shown or discussed more generally in order to avoid obscuring the invention. In many cases, a description of the operation is sufficient to enable one to implement the various forms of the invention, particularly when the operation is to be implemented in software. It should be noted that there are many different and alternative configurations, devices and technologies to which the disclosed inventions may be applied. The full scope of the inventions is not limited to the examples that are described below.

Overview

[0056] Implementations of the present invention as disclosed herein depart significantly from the conventional concepts and designs of the prior art. This invention provides a device to load cargo into an unmanned aerial vehicle (UAV) for transport without human intervention and has the ability to unload cargo from UAVs at the intended delivery location without human intervention. The loading and unloading of cargo is accomplished with limited complexity, with the implementation of the invention at the pickup and delivery locations. This enables the rapid deployment of UAV pickup and delivery to a multiplicity of consumer delivery and pickup locations.

[0057] Implementations of the invention are comprised of two major elements: 1) a payload pad L1, (See FIGS. 3 and 8-10), that is a low cost, passive element that can be rapidly deployed to a plurality of UAV delivery points and elements of which will additionally be deployed at the UAV loading points including vehicles and package disbursement centers such as retailers, fulfillment centers and package carriers’ hubs among others; and 2) a payload container P1 that is permanently, semi-permanently, or detachably secured to a UAV and is used to load cargo from a payload pad L1 without human intervention and securely transport the cargo to a delivery location where it can unload without human intervention.

Payload Container Enclosure

[0058] As shown in FIG. 1, the payload container P1 is a secure container used to carry cargo from an originating point to an intended destination on a UAV. In at least one embodiment, the payload container P1 is constructed of five fixed panels, P2, P3, P6 shown in FIG. 1. The five panels comprise a top panel P6 and four side panels P2, P3 of the payload container P1. The bottom of the payload container is formed from two movable panels C10, C11, shown in FIG. 2, which form the payload container cargo door for cargo loading and unloading and are described separately in more detail. Additionally, there are carbon fiber panels P7 on each side of the payload container P1 that provide cover and protection for the mechanisms that operate the payload container doors C10, C11 and improve the aerodynamics of the payload container P1 during flight. In alternate implementations, the payload container enclosure panels can be constructed of other lightweight materials with the requisite mechanical properties for strength and durability, such as by non-limiting example, a metal or a plastic. In other embodiments, the geometry of the payload container can be changed to meet specific requirements, for example, a hexagonal-shaped enclosure, or any other appropriate shape that is conducive to transporting differently shaped cargo.

Payload Container Attachment

[0059] The payload container P1 may comprise the mechanical attachment components P4 to attach the payload container to the UAV. These components P4 and the location of their attachment to the payload container P1 are adapted to the specific needs of the UAV to which they are affixed and to the specific configuration of the payload container P1. The payload container attachments P4 also include the electrical connectors P5 that provide the power transfer and the electronic communication between the payload container and the UAV.

Payload Container Doors

[0060] In at least one embodiment of the invention, the payload container cargo doors C10, C11 comprise two carbon fiber panels that, when closed, form the bottom panel in the payload container C10, C11, shown in FIG. 3. During the loading and unloading sequences of the payload container operation, cargo is required to move laterally relative to the cargo edges S3, S4 when in contact with these upper cargo door surfaces S6 as shown in FIG. 4. Therefore, in at least one embodiment of this invention, the payload container doors comprise one or more materials having a coefficient of friction that is less than or equal to about 0.2 so as to reduce the fricative force of the upper surfaces S7 of the cargo doors C10, C11 when in contact with the cargo. In at least one embodiment of the payload container doors C10, C11, a thin sheet of ultrahigh molecular weight polyethylene (UHMWPE) material S6 may be affixed to the surface S7 of these doors. To further assure that the cargo is able to move relative to the payload container doors during the loading and unloading processes, in at least one embodiment, the payload container doors comprise a thin sheet of low friction para-aramid synthetic fiber such as Kevlar® or other similar materials that is attached to the exterior edge of the door on the interior surface S7 shown in FIG. 4. This low friction sheet is of flexible material and in some embodiments, is only attached at the outer edge of the doors and drapes down over the doors C10, C11 when the doors C10, C11 are fully opened. As the doors close, the edges of the cargo S3, S4 loaded during the cargo loading process are placed in contact with the interior surface of the low friction sheet S7. As the payload container doors C10, C11 continue to close, the edge (or corner) S3, S4 of the cargo resting on the low friction sheet S7 slides on the sheet S7 causing the sheet to gather into one or more folds or ridges T1 shown in FIGS. 5-6, toward the exterior edges of the payload container door C10, C11 thereby lifting the cargo from the payload pad L1 shown in FIG. 6. This motion continues until the payload container doors C10, C11 are fully closed against the payload container enclosure and the cargo is fully contained inside the payload container P1.

[0061] In some embodiments, the UHMWPE and para-aramid synthetic fiber or equivalent may be replaced with a small belt conveyor segment W1 on the payload container doors as shown in FIG. 16. This belt conveyor segment W1 may approximate the full, unimpeded width and length of the payload container doors C10, C11 and may be powered or unpowered. A powered conveyor belt segment could include a separate electrical motor or a ratcheting device that generates its movement from the closure of the payload container cargo doors.

Payload Container Door Connector Links

[0062] In at least one embodiment of the invention, each payload container cargo door is affixed to the payload container by two connector links attached to both short edges of each payload container cargo door for four connector links per door C2, C3 in FIG. 5. The attachment of each connector link to the payload container cargo door permits each connector link to rotate around the point at which they are pivotally connected. The other ends of these connector links are affixed to the payload container panels on the ends of the payload container, and these attachments will also allow the rotation of each link around the point to which they are pivotally connected.

[0063] In at least one embodiment of the invention, there are two motive force links attached to both exterior edges of the short edge of each of the two payload container cargo doors C4 shown in FIG. 5. The motive force links’ attachment points on these doors are near the long edge of the payload container cargo door at the center of the payload container when the payload container cargo doors are closed. In at least one embodiment of the invention, the other end of the motive force links is attached to a slider block C7 shown in FIG. 3, that is driven by a lead screw C8 shown in FIG. 2, that moves the slider block in a motion perpendicular to the payload container cargo doors when they are in a closed position. In other embodiments of this invention, this motive force can be applied by other suitable linear actuators such as a pneumatic or hydraulic cylinder. In other embodiments, this motive force can be applied by multiple lead screws or pneumatic or hydraulic cylinders. In other embodiments of this invention, the motive force can be supplied by linkages attached to rotating elements driven by electrical, pneumatic, or hydraulic mechanisms. These links provide the force to move the cargo doors into an open position or move them into a closed position.

[0064] The connector links, the payload container cargo door, and the payload container panel form the four elements of a four-bar linkage which is moved by the motive force links to create a motion path for the doors that are designed to intersect with the bristles or other support elements of the payload pad at a point below their contact with the cargo shown in FIG. 4, causing the bristles or other support elements to deflect or otherwise release the cargo onto the cargo doors as they move in a scooping motion through the bristles or other support elements underneath the cargo and then move with a vertical motion component to lift the cargo into the payload container.

[0065] In alternate implementations of the invention, the attachment point of one or both connector links to the payload container panels may be modified by adding additional linkages U2 shown in FIG. 11 and suitable electrical motors, lead screws, pneumatic or hydraulic devices U1, to vary the attachment point of the linkage U3 to the payload container to modify the movement of the payload container cargo doors to improve their ability to lift/lower larger, heavier or irregular shaped cargo from/to the payload pad, into and out of the payload container.

Payload Pad

[0066] The payload pad shown in FIGS. 8-10 comprises a base R3 that provides an attachment point for the support elements L2 that support the cargo when the cargo is placed on it. This base R3 constrains these elements appropriately to permit them to support the cargo in the ready-for-pickup state and then release the cargo onto the payload container cargo doors C10, C11 when the payload container cargo doors are closing and thereby intersect the support elements as occurs during the cargo pickup operation.

[0067] In at least one embodiment of the invention, the support elements of the payload pad L1 are bristles R1 of an appropriate length and cross-section and formed from a material that has the appropriate mechanical properties that enable them to support cargo that meets the cargo weight and shape criteria for the payload pad L1, when the payload pad L1 is in its ready-for-pickup state. During the cargo pickup process, the payload container cargo doors C10, C11 intersect these bristles R1 and cause the bristles R1 to deflect, which reduces the ability of the bristles R1 to support the cargo, thereby lowering the cargo until it contacts the payload container cargo doors C10, C11.

[0068] In an alternate embodiment shown in FIGS. 23-25, the function of the support elements may be comprised of suitable elastomeric foam material. In this embodiment, the payload pad L1 comprises a base R3 supporting an inverted T-shaped rigid element F3 to which are adhesively attached foam elements F1 and F2, the foam elements suitable to support any rotational force that may be created by the cargo L3 asymmetrical force on the rigid element F3. A flexible fabric F4 may be adhesively attached to the foam blocks F1 and F2 and is coupled to the rigid element F3. In this embodiment, the payload container doors C10, C11 comprise a roller F5 or rounded element of low friction material such having a coefficient of friction less than or equal to about 0.2 such as by non-limiting example, UHMWPE. The flexible fabric F4 comprises a high-strength fabric such as para-aramid synthetic fiber such as Kevlar® with embedded fiberglass strands or similar material arranged to limit any deformation of length. The attachment of the fabric F4 to the rigid element F3 causes the deformation of the foam block by the closing of the payload container door F5 to pull the fabric from the edge of the foam block F6, keeping the cargo stable on the foam blocks. The payload container doors and their mechanical linkages are such that the opening and closing movement does not create any contact between the payload container doors and the rigid element F3 by keeping the height of the roller F8 above the height of the rigid element F7 during the door closing movement.

[0069] In alternate embodiments, the support elements can comprise a mechanical linkage with a hinge point near the base that also has a hinge point nearer the midpoint of the linkage, the hinge points being limited in motion and in opposite directions. The hinge points in the fully erect orientation can be biased in that orientation by magnetic force or mechanical design features such as a spring that can be overcome or released by the payload container cargo doors during the cargo pickup operation.

[0070] In alternate embodiments, the support elements can be comprised of tines hinged near the connection to the payload pad base. These tines can be held in their upright state by mechanical properties of their design (for example, detents on the edges of the tines held in place by a spring) or magnetic or other devices.

[0071] In alternate embodiments shown in FIGS. 16-19, the support elements can be comprised of rollers W2 that are arranged such that their long axis is substantially parallel to the bottom of the cargo L3 and substantially perpendicular to the horizontal vector of the payload container’s cargo door C11 movement during the loading and unloading operations where the rollers are released as the payload container’s cargo doors C10, C11 are moved to a position to accept the weight of the cargo and where this release can be caused by the mechanical movement of the payload container doors, by electrical devices, by electromagnetic devices, by mechanical linkages to other components or other devices that may be caused by or triggered by the cargo doors movement and position.

[0072] The payload pad L1 also provides one or more guidance elements that enable the UAV to make the precision landing at the payload pad L1, enabling the loading and unloading of the cargo into and out of the payload container as described herein. These guidance elements may be visible marks (e.g. optical fiducials) as shown in FIGS. 8-10 placed in consistent locations on the payload pad.

Cargo Loading Operation

[0073] The cargo loading operation of a UAV equipped with a payload container P1 may take one of two forms depending upon which of the one or more embodiments of the invention is utilized. The first form may involve a load of cargo being loaded into a payload container at a depot that has UAV loading/ unloading apparatus that incorporates a payload pad. A suitably equipped depot may be a logistic center, a retail location, a mobile cargo-carrying device, or another structure. The second form may be the loading of cargo at a location with only a payload pad where cargo is manually placed upon or retrieved from the payload pad.

[0074] When loading a UAV equipped with a payload container at a suitably equipped depot, the depot may utilize an apparatus which incorporates the payload pad. The UAV at the depot is positioned in the cargo loading position. The UAV may instruct the payload container to fully open the payload container cargo doors. After the payload container has opened the cargo doors, the payload container may inform the UAV, which will inform the depot of readiness for loading the cargo. The depot may then retrieve the cargo and place it on a payload pad attached to an apparatus designed to move the cargo L3 shown in FIG. 3 to the correct position for loading. When the cargo is in the load position, the depot may then inform the UAV. The UAV then instructs the payload container to close the payload container cargo doors. During the movement of the payload container cargo doors C10 and C11 toward the closed position, the interior edges of the payload container cargo doors intersect with the bristles of the payload pad L2 that are supporting the cargo. As the payload container cargo doors close, their lateral pressure on the bristles causes the bristles to flex S1 at the point of contact with the cargo as shown in FIG. 4, reducing their capacity to support the cargo. When enough of the bristles are in the flexed state, the combined supporting force of the bristles on the cargo is reduced to less than the weight of the cargo, which thus allows the cargo to slump down onto the payload container cargo doors C10, C11. Alternatively, for packages of a sufficiently light enough weight, the doors continue to close and eventually lift the package off the unflexed bristles. The cargo edges then rest on the anti-friction sheet, which rests on the UHMWPE portion of the payload container cargo doors. Further movement of the cargo doors raises the cargo off the bristles and causes the payload container door to move laterally relative to the edges of the cargo resting on the anti-friction sheet T1, toward the center of the payload container cargo door opening S3, T1 shown in FIG. 6. The anti-friction sheet limits the lateral forces on the payload container cargo doors. When the payload container cargo doors have been fully raised and closed, the cargo is entirely and securely positioned inside the payload container.

[0075] Loading cargo into the payload container at a remote location requires the remote location’s resources to place suitable cargo in the correct location and orientation on the payload pad L1 shown in FIG. 3. The person or machine that places the cargo L3 shown in FIG. 3 on the payload pad informs the UAV control system that the cargo is ready for loading and transport. The UAV equipped with a payload container is dispatched to that location. Once the UAV arrives at the remote location, it instructs the payload container to open the payload container cargo doors. The UAV may utilize the landing guidance equipment such as the fiducials on the payload pad to guide its precision landing. The UAV may then verify the payload container cargo doors are fully opened before completing the landing procedure.

[0076] After the landing has been completed, the UAV may instruct the payload container to execute the loading procedure by closing the payload container cargo doors C10, C11 shown in FIG. 5. During the movement of the payload container cargo doors toward the closed position, the interior edges of the payload container cargo doors intersect with the bristles L2 shown in FIG. 4 of the payload pad that are supporting the cargo. As the payload container cargo doors close, the lateral pressure on the bristles causes the bristles to flex S1 at the point of contact with the cargo which reduces the capacity of the bristles to support the cargo. When enough of the bristles are in the flexed state, the combined force of the bristles on the cargo is reduced to less than the weight of the cargo, which causes the cargo to slump down onto the payload container cargo doors. The cargo edges S3, S4 may rest on the anti-friction sheet, which rests on the UHMWPE portion of the payload container cargo doors. Alternatively, for packages of a sufficiently light weight, the doors continue to close and eventually lift the package off the unflexed bristles. Further movement of the doors raises the cargo off the bristles and causes the payload container cargo doors to move laterally relative to the edges of the cargo resting on the anti-friction sheet T1, toward the center of the payload container cargo doors opening. The anti-friction sheet limits the lateral forces on the payload container cargo doors. When the payload container cargo doors have been fully raised and closed, the cargo will be entirely and securely inside the payload container.

Cargo Unloading Operation

[0077] The cargo unloading operation of a UAV equipped with a payload container has two general modes. One mode of unloading operation herein referred to as remote unloading, entails the unloading of the cargo in a manner that prevents the payload container from closing the cargo doors and requires the UAV to return to flight with the cargo doors open. The remote unloading operation will require the UAV to determine that the UAV is in the correct location and orientation prior to initiating the payload container unloading apparatus. Another mode of unloading herein referred to as depot unloading, entails the unloading of cargo in a manner that does not prevent the payload container from closing the payload container cargo doors after the unloading operation is complete, permitting the UAV to return to flight or otherwise move from the unloading position with the cargo doors closed. The depot unloading operation may require the depot apparatus to determine that the payload container and the depot apparatus are in the correct location and state prior to initiating the payload container unloading apparatus.

[0078] The remote unloading operation requires a planar surface onto which the cargo can be unloaded referred to herein as “the unloading surface.”

[0079] One embodiment of the unloading surface is the planar surface created by the top ends of the bristles R1 of the payload pad shown in FIG. 10. The unloading surface may be at least partially surrounded by a coplanar surface, referred to herein as “the landing surface,” of sufficient dimension to permit the UAV to land on that surface at an elevation relative to the unloading surface that is sufficient to permit the opening and closing of the payload container cargo doors. In a typical configuration, the combined elevation of the unloading surface and the height of the cargo after it has been unloaded onto that surface is such that the payload container cargo doors are unable to close after the cargo has been unloaded. The remote unloading operation provides the navigation aids, for example, the fiducials R2 shown in FIG. 9., that guide the UAV to land in the correct location and orientation. Prior to engaging the payload container’s unloading apparatus, the UAV control system may validate that it is in the correct location, orientation and state.

[0080] The unloading process comprises the movement of the lead screw C8 which in turn causes the lead screw follower C7 contained between the lead screw follower guides C9 to move downwardly, moving the upper end of the linkage C4, which causes the payload container doors C10, C11 to move downwardly and outwardly as determined by the linkages C2, C3. The motion of the lead screw follower is continued until the cargo doors C10, C11 are fully opened, as shown in FIG. 3. where the upward and inward corners S3, S4 of the cargo are vertical to the inside surface of the payload container’s walls P3 as shown in FIG. 1. assuring the cargo is completely released from the payload container. The payload container cargo doors may report to the UAV that it has completed the unloading process.

[0081] The depot unloading operation may be performed at a suitably equipped depot where a suitably equipped depot could be a logistic center, a retail location, a mobile cargo-carrying device, or another structure. The depot unloading operation requires design features or mechanical or human resources at the unloading location to receive and move the unloaded cargo downwardly or to move the UAV with the attached payload container upwardly to a distance such that the unloaded cargo does not impede the closing motion of the payload container cargo doors.

[0082] This physical separation of the top of the unloaded cargo and the lowest position of the payload container cargo doors during an opening or closing cycle, can alternatively be created by a cargo unloading position that is above a cavity of sufficient length, width and depth such that after the cargo is unloaded into the cavity, the tallest point of the unloaded cargo will be below the arc of the payload container cargo doors during the open/close cycle.

[0083] For the depot unloading operation the depot may provide the navigation aids to guide the landing of the UAV and may provide additional apparatus to move the UAV and position it over the depot’s unloading apparatus. The depot control may inform the UAV when the UAV is correctly positioned and the depot is in a state that is ready to receive the cargo. The UAV control system instructs the payload container to unload the payload container. The payload container engages the payload containers unloading apparatus.

[0084] The payload container may deactivate any cargo stabilization devices that may have been activated. The payload container may then engage the cargo door operating mechanism by energizing the lead screw motor C6 shown in FIG. 2. Movement of the lead screw C8 in turn causes the lead screw follower C7 contained between the lead screw follower guides C9 to move downwardly, thereby moving the upper end of the linkage C4, which causes the payload container doors C10, C11 to move downwardly and outwardly as determined by the linkages C2, C3.

[0085] The cargo L3 may then slide down the low friction sheet S7 until it rests on the cargo supporting members L2.

[0086] The motion of the lead screw follower is continued until the cargo doors C10, C11 are fully opened as shown in FIG. 3. where their upward and inward corners are vertical to the inside surface of the payload container’s walls P3 shown in FIG. 1. assuring the cargo is completely released from the payload container.

[0087] In places where the description above refers to particular implementations of systems and methods for cargo delivery by unmanned aerial vehicles it should be readily apparent that a number of modifications may be made without departing from the spirit thereof and that these implementations may be applied to other to systems and methods for cargo delivery by unmanned aerial vehicles.