GB2576504A

GB2576504A - An apparatus

Info

Publication number: GB2576504A
Application number: GB1813512.9A
Authority: GB
Inventors: William Geoffrey Feather Stewart; Raymond Longfield Alan; Michael Chapman Lee; Macallan Feather Sean
Original assignee: Engineering Ltd Firma
Current assignee: Engineering Ltd Firma
Priority date: 2018-08-20
Filing date: 2018-08-20
Publication date: 2020-02-26
Anticipated expiration: 2038-08-20
Also published as: GB2576504B; GB201813512D0

Abstract

System and apparatus 10 for the deployment and retrieval of an unmanned aerial vehicle (UAV) 12. The unmanned aerial vehicle has a body 18 with a mounting arrangement 22 and an envelope 20 attached to the mounting arrangement. The envelope defines an internal gas chamber configured to be inflated with gas from a gas source and configured to be deflated. A capsule 14 defines an internal chamber for receiving the unmanned aerial vehicle therein. The capsule includes an engagement arrangement 26 for releasably mounting the unmanned aerial vehicle within the capsule, and an opening 16 intended to be uppermost in use and configured such that the unmanned aerial vehicle is able to pass through said opening. The capsule also includes a retrieval arrangement configured such that, when the unmanned aerial vehicle is mounted in the capsule, movement of the body with respect to the capsule retracts the envelope into the capsule chamber.

Description

An Apparatus

FIELD OF THE INVENTION

The present invention relates to an apparatus for the deployment and retrieval of an unmanned aerial vehicle; a delivery system for an unmanned aerial vehicle; an unmanned aerial vehicle; a capsule for receiving an unmanned aerial vehicle; and/or to a method of use of an apparatus for the deployment and retrieval of an unmanned aerial vehicle.

BACKGROUND OF THE INVENTION

Unmanned aerial vehicles (UAVs), also known as drones, can be used for the inspection and surveillance of large restricted spaces such as nuclear cells, contaminated buildings, large storage tanks, large pressure vessels etc.

Use of such a UAV within such restricted spaces enables an operator to understand and map: the current layout of the interior space (i.e. allowing prior data/understanding to be compared/updated); the condition of the interior space as well as the integrity thereof; and an inventory of what is present in the interior space.

Due to the restricted entry points through which the UAVs may be utilised, difficulties are typically experienced in the deployment and retrieval of the UAV. Additionally, in light of the difficulty associated with accessing the interior space, it is important that the maximum flight time of the UAV be improved.

The present invention seeks to overcome or at least mitigate one or more problems associated with the prior art.

SUMMARY OF THE INVENTION

A first aspect of the invention provides an apparatus for the deployment and retrieval of an unmanned aerial vehicle, the apparatus comprising: an unmanned aerial vehicle comprising a body having a mounting arrangement and an envelope attached to the mounting arrangement, wherein the envelope defines an internal gas chamber configured to be inflated with gas from a gas source and configured to be deflated; and a capsule defining an internal chamber for receiving the unmanned aerial vehicle therein and comprising: an engagement arrangement for releasably mounting the unmanned aerial vehicle within the capsule; and an opening intended to be uppermost in use and configured such that the unmanned aerial vehicle is able to pass through said opening; wherein the capsule comprises a retrieval arrangement configured such that, when the unmanned aerial vehicle is mounted in the capsule, movement of the body with respect to the capsule retracts the envelope into the capsule chamber.

Initially, the envelope of the unmanned aerial vehicle is inflated with gas that is lighter than air from a gas source. When the envelope is filled with a gas, for example Helium, the buoyancy of the UAV is such that it is able to remain substantially stable in the air. When the vehicle is disengaged from the capsule, the vehicle is propelled by a propulsion system to carry out surveillance. After carrying out surveillance, the vehicle returns to the apparatus. The body is received in the capsule and the envelope is deflated.

Moving the unmanned aerial vehicle within the capsule enables the entirety of the unmanned aerial vehicle (i.e. body and deflated envelope) to be retrieved without the need for manual intervention. This is particularly advantageous when the unmanned aerial vehicle is operating in spaces with limited accessibility.

The unmanned aerial vehicle and the capsule may comprise complementary alignment features for aligning the body of the unmanned aerial vehicle substantially centrally within the opening.

This arrangement aids in the retrieval of the unmanned aerial vehicle by facilitating the correct positioning of the body (e.g. along two axes perpendicular to the elongate axis of the capsule), which positions the UAV such that the capsule is able to engage the body ofthe UAV.

The opening may be configured to conform to a portion of the UAV. The opening may define a perimeter, and at least a portion of said perimeter may define a curved profile configured to conform to a portion ofthe unmanned aerial vehicle.

Further aids in centring the unmanned aerial vehicle within the capsule prior to retrieval.

The curved profile may be configured to conform to a portion of an underside of the envelope, when the envelope is inflated with a gas.

This enables the unmanned aerial vehicle to be centrally located within the opening without the body engaging the capsule, which works to minimise damage to the envelope.

The engagement arrangement may rotatably mount the unmanned aerial vehicle within the capsule.

Rotatably mounting the unmanned aerial vehicle within the capsule enables the deflated envelope to be retrieved by wrapping around the body during rotation thereof. This provides a compact way of retrieving the deflated envelope.

The body may be substantially tubular. The tubular body may have a maximum outer diameter of between 2-10 (5-25cm), between 4-8 (10-20cm), e.g. approximately 6 (15cm).

The tubular body may comprise an enlarged region of increased diameter. The mounting arrangement may be provided on said enlarged region.

Providing the mounting arrangement on an enlarged region of the tubular body has been found to aid in the process of wrapping the deflated envelope around the body during retrieval of the unmanned aerial vehicle.

The tubular body may define an axis. The enlarged region may be positioned substantially centrally along said axis.

This has been found to further aid in the wrapping the envelope back around the body during the retrieval process by providing a more compact wrapping of the deflated envelope around the body.

The tubular body may comprise shoulder regions at opposing ends of the enlarged region. The shoulder regions may be curved or inclined.

This provides a smoother retrieval of the envelope when it is being wrapped around the body. This arrangement also allows the deflated envelope to be more smoothly funnelled and retracted into the capsule.

The opening may define a cross-sectional profile having opposing end region. The opposing end regions may be curved or angled in a direction away from the body, when the body is received within the chamber.

Having end regions of the opening that are curved or angled away (i.e. upwards) allows the deflated envelope to be easily funnelled and retracted in to the capsule without getting caught on the edges.

The engagement arrangement may be configured to position the body substantially centrally within the capsule.

This aligns the body along the two axis that are perpendicular to the elongate axis of the body, which correctly positions the body within the capsule such that it is possible to connect/engage the body to a drive member, a gas in/out line, power cables or the like.

The engagement arrangement may comprise opposing articulated members configured for receiving an end of the body therebetween.

The capsule may be substantially tubular. The tubular capsule may define a maximum diameter of between approximately 2-10 (5-25cm), preferably in the region of 4-8 (10-20cm), for example approximately 6 (15cm).

The unmanned aerial vehicle may comprise a propulsion arrangement configured to propel the unmanned aerial vehicle, when the balloon is inflated.

The apparatus may further comprise a drive member, e.g. a drive shaft, for rotating the unmanned aerial vehicle within the capsule.

The drive member may be configured for connecting the unmanned aerial vehicle to a gas source for selectively inflating the envelope with a gas that is lighter than air, and for deflating the envelope.

The envelope may be provided with a dump valve, where said valve can be opened to discharge the gas therein.

The capsule may comprise an ejection device configured to disengage the unmanned aerial vehicle from the engagement arrangement prior to deployment.

The ejection device may be configured to position the body substantially centrally within the opening.

This arrangement ensures that the body of the vehicle does not hit the perimeter of the opening during take-off and aids with ensuring clearance between the body and the engagement arrangement.

According to a second aspect of the invention, there is provided a delivery system for an unmanned aerial vehicle, the system comprising: an apparatus according to the first aspect; and a delivery tube configured for extending through an aperture in a wall structure; wherein the delivery tube comprises an opening intended to uppermost in use, and wherein the delivery tube is configured for receiving the apparatus at an end thereof; and wherein the delivery system comprises a positioning arrangement for positioning the capsule opening within a perimeter of the delivery tube opening.

During operation of the unmanned aerial vehicle, the envelope will be inflated such that the unmanned aerial vehicle is deployed from the capsule. The vehicle will travel around a space e.g. in order to carry out surveillance, and will then travel back to the capsule and the envelope will be deflated. Rotation of the vehicle within the capsule causes the deflated envelope to wrap around the body such that the deflated envelope is drawn back into the capsule. This delivery system allows the unmanned aerial vehicle to be inserted through an opening in a wall, deployed, and then retrieved.

The delivery tube may be substantially tubular. The capsule may be substantially tubular. The tubular capsule may define a maximum diameter of between approximately 2-10 (5-25cm), preferably in the region of 4-8 (10-20cm), for example approximately 6 (15cm).

According to a third aspect of the invention there is provided an unmanned aerial vehicle comprising: a body having a mounting platform; and an envelope attached to the mounting platform, wherein the envelope defines an internal gas chamber configured to be inflated with gas from a gas source and configured to be deflated; and wherein the capsule further comprises an engagement arrangement for releasably mounting the unmanned aerial vehicle within a capsule, and wherein the envelope is configured to wrap around the body, when deflated.

According to a fourth aspect of the invention there is provided a capsule for receiving an unmanned aerial vehicle, the capsule comprising: an internal chamber for receiving an unmanned aerial vehicle therein; an opening intended to be uppermost in use and configured such that an unmanned aerial vehicle is able to pass therethrough; an engagement arrangement for releasably mounting an unmanned aerial vehicle within the capsule; and a retrieval arrangement configured such that, when an unmanned aerial vehicle is mounted in the capsule, the retrieval arrangement is configured to move said unmanned aerial vehicle with respect to the capsule in order to retract an envelope of an unmanned aerial vehicle into the chamber.

According to a fifth aspect of the invention there is provided a method of use of the apparatus according to the first aspect, the method comprising the steps of: a) inflating the envelope with a gas from a gas source; b) disconnecting the unmanned aerial vehicle from the gas source; c) disengaging the unmanned aerial vehicle from the engagement arrangement; and d) propelling the unmanned aerial vehicle away from the capsule.

According to a sixth aspect of the invention there is provided a method of use of the apparatus according to the first aspect for retrieval of the unmanned aerial vehicle, the method comprising the steps of: a) receiving the unmanned aerial vehicle within the capsule via the opening; b) mounting the unmanned aerial vehicle to the capsule with the engagement arrangement; c) deflating the envelope; and d) moving the body within the capsule such that the envelope is retracted into the capsule chamber.

BRIEF DESCRIPTION OFTHE DRAWINGS

Embodiments of the invention will now be described with reference to the accompanying drawings, in which:

Figure 1 is a side view of an apparatus according to an embodiment;

Figure 2 is a plan view ofthe apparatus of Figure 1 with the envelope removed for clarity;

Figure 3 is a side view of an unmanned aerial vehicle according to an embodiment;

Figure 4 is an isometric view of the unmanned aerial vehicle of Figure 3 with the envelope removed for clarity; and

Figure 5 is a schematic side view of a delivery system according to an embodiment.

DETAILED DESCRIPTION OF EMBODIMENT(S)

Referring firstly to Figures 1 and 2, an apparatus 10 for the deployment and retrieval of an unmanned aerial vehicle (UAV) 12 is illustrated.

The apparatus 10 includes a capsule 14 defining an internal chamber in which the UAV 12 is positioned. The capsule 14 includes an opening 16 intended to be uppermost in use, as is illustrated.

The UAV 12 includes a body 18 and an envelope 20 attached to the body 18. That is, the body 18 includes a mounting arrangement 22, and the envelope 20 is attached to the mounting arrangement 22. The opening 16 is dimensioned such that the body 18 of the UAV 12 can pass therethrough during take-off and landing.

The apparatus 10 and UAV 12 are configured such that the envelope 20 can be inflated with gas from a gas source (not shown) and can be deflated. In use, the envelope 20 is filled with a gas that is lighter than air, for example Helium, to provide lift to the UAV 12. When the envelope 20 is able to be filled with a gas such the buoyancy of the UAV 12 allows the UAV 12 to remain substantially stable in the air. In practice, the buoyancy of the UAV 12 will be such that the UAV 12 slowly falls down to the ground, without any additional propulsion. In order to deflate the envelope 20, the apparatus 10 is first disconnected from the gas source, and is then connected to a vacuum system (not shown). Although not illustrated, in alternative arrangements, the envelope 20 may be provided with a dump valve, where said valve can be opened to discharge the gas therein, removing the need for a vacuum system.

The capsule 14 includes a retrieval arrangement. When the UAV 12 is mounted within the capsule 14, the retrieval arrangement is configured to move the UAV 12 with respect to the capsule 14 so as to retract the envelope 20 into the capsule 14. This movement may be rotational movement of the body, or axial movement of the body 18 along the length of the capsule 14. The internal dimensions of the chamber of the capsule 14 are such that both the body 18 and the deflated envelope 20 are able to be rotated therein.

The retrieval arrangement is provided in the form of a drive member configured to rotate the UAV 12 within the capsule 14 (i.e. to provide wrapping torque to the vehicle 12). In the present embodiment, the drive member is provided as a drive shaft 24. The drive shaft 24 allows components to pass through the centre thereof to enable the transfer of gases to/from the UAV 12. A further communication port (not shown) is provided to enable the transfer of electrical and digital communications to/from the UAV 12. Such an additional communication port may be provided as an additional drive shaft proximate to the drive shaft 24.

In use, the envelope 20 will be inflated with gas from a gas source, the UAV 12 will be disengaged from the capsule 14, thus allowing the UAV 12 to begin flight. When the UAV 12 returns to the apparatus 10, the body 18 is received in the capsule 14 through the opening 16, and the envelope 20 is deflated. The drive means engages the body 18. Rotation of the UAV 12 within the capsule 14 draws the envelope 20 into the capsule 14, and causes the deflated envelope 20 to wrap around the body 18, such that the entire UAV 12 can be retrieved without manual intervention.

The envelope 20 is provided with a mount 27 for a camera 28. The camera 28 enables the UAV 12 to carry out surveillance of an area. In some arrangements, the UAV 12 may include additional cameras positioned and directed substantially downward, forward, and upward. Although not illustrated, the UAV 12 may also be provided with a transmission system for transmitting the surveillance data via cables provided within the drive shaft 24, when the UAV 12 is mounted to the capsule 14. The transmission system may allow the UAV 12 to have a 'live feed' to an operator.

In order to aid in the retrieval of UAV 12 into the capsule 14, the UAV 12 and the capsule 14 are provided with complementary alignment features. The complementary alignment features work to align the body 18 substantially centrally within the opening 16. That is, the alignment features are configured to align the body 18 centrally within the capsule 14 along two axes perpendicular to the elongate axis of the capsule 14.

In the illustrated embodiment, the complementary alignment features are provided in the form of a portion of the opening 16 that is configured to conform to a portion of the UAV 12. More specifically, a portion of the opening perimeter defines a curved profile 29 that conforms to an underside ofthe inflated envelope

20. The profile of the curved region 29 is such that the inflated envelope 20 rests at the correction height within the capsule, and at the correct position with respect to the perimeter of the opening 16 to enable the capsule 14 to engage the body 18. It will be appreciated that in alternative arrangements, different alignment features may be used to correctly position the body 18 within the capsule 14.

The opening 16 defines an elongate profile having opposing end regions 42, 44. The profile includes a substantially linear central region 46 extending between the end regions 42, 44. The curved alignment region 29 is provided along the central region 46. As is shown in Figure 1, the opening 16 is recessed into the tubular capsule 14 such that the end regions 42, 44 are upwardly curved (i.e. curved in a direction away from the body 18, in use). In alternative arrangements, the end regions may be linear and inclined. The upwardly curved or angled end regions 42, 44 reduces the possibility of the envelope 20 becoming caught or stuck at the end regions. Put another way, the profile of the opening 16 allows the deflated envelope 20 to be more smoothly funnelled and retracted into the capsule 14.

Although not illustrated, the capsule 14 may be provided with one or more cameras positioned thereon in order to provide a visual aid to the operator when initially aligning the UAV 12 with the capsule 14. In some arrangements, the cameras may be retractable within the capsule 14.

The capsule 14 is also provided with an engagement arrangement 26 for releasably and rotatably mounting the UAV 12 within the capsule 14.

In the illustrated embodiment, the engagement arrangement 26 is provided in the form of first and second engagement sleeves 30, 32 provided proximate the opposing ends ofthe elongate capsule 14.

The first engagement sleeve 30 is moveable such that, when the body 18 is positioned in the correct location, the sleeve 30 moves towards a first end 34 of the body 18. Further movement of the first engagement sleeve 30 moves the body 18 such that a second end 36 of the body 18 engages the second engagement sleeve 32. The engagement arrangement 26 also includes an arrangement to position the body 18 substantially centrally within the capsule 14, prior to engagement of the first and second engagement sleeves 30, 32. That is, the engagement arrangement is configured to align the body 18 centrally within the capsule 14 along two axes perpendicular to the elongate axis of the capsule 14.

In the illustrated embodiment, the engagement arrangement 26 includes opposing articulated members 38. The alignment arrangement described above works to position first end 34 of the body 18 between the opposing members 38. The members 38 work to provide a smoother and more reliable engagement between the capsule 14 and the body 18. In order for the engagement arrangement 26 to engage and disengage the body, a drive means is provided. In the illustrated embodiment, the drive shaft 24 is the drive means, although a separate drive means may be provided in alternative arrangements.

The articulated members 38 also aid in the disengagement of the body 18 from the second engagement sleeve 32. When the second engagement sleeve 32 is disengaged, as the first engagement sleeve 30 is retracted, the body 18 may also be retracted, e.g. due to friction. In order to reliably disengage the body 18 from the first engagement sleeve 30, the capsule is provided with an ejection device 40. The ejection device 40 is configured to position the body 18 substantially centrally within the opening 16 as it disengages from the engagement arrangement 26. In the illustrated embodiment, the ejection device 40 is provided in the form of an ejection pin, although any suitable ejection device may be used.

Referring now to Figures 3 and 4, the UAV 12 is illustrated.

The body 18 is substantially tubular in shape and defines an elongate axis between the first and second ends 42, 44. The body 18 has an enlarged region 48 of increased diameter and the mounting platform 22 is provided on said enlarged region 48. In the illustrated embodiment, the enlarged region 48 is positioned substantially centrally along the elongate axis of the body 18. Positioning the mounting platform 22 on an enlarged portion of the body 18 has been found to result in a more compact wrapping of the deflated envelope 20 around the body 18.

The mounting arrangement 22 is provided in the form of a mounting platform configured to conform to the geometry of the envelope 20. In the illustrated embodiment, the mounting platform 22 is curved to correspond to the underside portion of the envelope 20.

The transition region between the body 18 and the enlarged region 48 are provided as two angled shoulder portions. That is, the tubular body 18 includes shoulder regions 49 at opposing ends of the enlarged region 48. The shoulder regions 49 remove an abrupt transition between the enlarged region 48 and the rest of the body 18, which works to provide a smoother retrieval of the envelope 20 as it is being wrapped around the body 18. In the illustrated embodiment, the shoulder regions 49 are linear and inclined, but may be curved in alternative arrangements. During stowing (rotation of body 18) the enlarged central region 48 draws the envelope 20 in more rapidly than at the first and second ends 42, 44, which causes the envelope 20 to be drawn to the centre of the body 18 reducing the number of rotations required to fully wrap the envelope 20 and retracting the envelope closer to the centre of the body 18 to allow the envelope 20 to wrap into a short length along the elongate axis.

In order to move the UAV 12 away from the capsule 14 (i.e. in order to travel around a space) to survey a space, the vehicle 12 is provided with a propulsion arrangement. In the illustrated embodiment, the propulsion arrangement includes two propellers provided at each opposing side of the central region 48. A first propeller 50 on each side provides lift, and a second propeller 52 on each side generates thrust. In alternative arrangements, any suitable number of propellers may be provided, such as one, two or more.

Referring now to Figure 5, the apparatus of Figures 1 and 2 is illustrated in situ within a delivery system 60.

The delivery system 60 includes an elongate delivery tube 62. As is illustrated, the delivery tube 62 is configured for extending through an aperture in a wall structure. A bracket 64 is also provided, to provide support to the delivery tube 62. However, it will be appreciated that the bracket 64 may not be required in some arrangements.

The delivery tube 62 is responsible for carrying the capsule 14 through the wall thickness to the far end of the delivery tube 62. It also allows for the transfer of utilities; gases, electrical, digital communications and or the support of mechanical components required for deployment and retrieval.

It will be appreciated that the delivery system and apparatus are configured such that the UAV 12 can be delivered through wall structures having a range of thickness, for example 0.5m, 2m or more. Further, in the illustrated embodiment the entire system is dimensioned such that the apparatus 10 and UAV 12 are able to be deployed through wall apertures down to six inches (15cm) in diameter. In the illustrated embodiment, the capsule 14 is provided as substantially tubular. The tubular capsule 14 defines a maximum diameter of approximately 6 inches (15cm) (i.e. the apparatus/capsule is able to be inserted through an aperture in a wall structure down to 6 inches (15cm) in diameter). It will be appreciated that in alternative arrangements the outer diameter of the capsule may be between approximately 2-10 (5-25cm), or approximately between 4-8 (10-20cm) (i.e. the apparatus/capsule is able to be inserted through an aperture in a wall structure between 2-10 (5-25cm), or between 4-8 (10-20cm) in diameter).

The delivery tube has an opening 68 at an end thereof for inserting and removing the apparatus 10 from the delivery tube 62. The delivery tube 62 also includes an opening 66 intended to be uppermost in use. The delivery tube opening 66 is dimensioned such that the foot print of the capsule opening 16 sits within its footprint.

The delivery system 60 is provided with a stop feature (not shown). In use, the capsule 14 travels along the delivery tube 62 and abuts the stop feature so as to align the opening 16 of the capsule 14 with the delivery tube opening 66.

Although not illustrated, the delivery tube 62 may be provided with one or more cameras positioned thereon in order to provide a visual aid to the operator when initially aligning the UAV 12 with the delivery tube 62. In some arrangements, the cameras may be retractable within the delivery tube 62.

Operation of the apparatus 10 will now be described.

Initially, the envelope 20 is in a deflated state within the capsule 14, and the UAV 12 is mounted within said capsule 14. Prior to disengaging the UAV 12 from the capsule 14, the envelope 20 is inflated with a gas from a gas source.

The sequence for disengaging the UAV 12 from the capsule 14 is as follows: fully inflating the envelope 20; disconnecting the UAV 12 from the gas source; disconnecting the UAV 12 from any electrical connections; disengaging the second end 36 of body 18 from the second engagement sleeve 32; and disengaging the articulated members 38 from first end 34 of the body 18. The sequence may also include the use of ejection device 40 to disengage the body 18 from the first engagement sleeve 30, and to correctly position the UAV 12 in the opening 16.

When the UAV 12 is disengaged from the capsule 14, a propulsion arrangement is used to propel the UAV 12 away from the capsule 14, in order to move around a space.

It will be appreciated that, if the delivery system 60 is being utilised for deploying the apparatus 10 through an aperture in a wall structure, the sequence for deployment may include the initial steps of inserting the apparatus 10 into the delivery tube 62; and positioning the opening 16 of the capsule 14 within a perimeter of the opening 66 of the delivery tube 62.

Upon completion of travelling around and surveying a space, the UAV 12 needs to be retrieved by the capsule 14.

The sequence for retrieving the UAV 12 back into the capsule 14 is as follows: the UAV 12 passes through the opening 16 so as to be received within the capsule 14; the engagement arrangement engages the body 18 of the UAV 12, as described above, such that the UAV 12 is mounted to the capsule 14; the envelope 20 is deflated by either connecting the envelope 20 to a vacuum system, or via a dump valve provided on the envelope 20; the body 18 is then moved within capsule 14 so as to fully retract the envelope 20 into the capsule chamber.

Although the invention has been described above with reference to one or more preferred embodiments, it will be appreciated that various changes or modifications may be made without departing from the scope of the invention as defined in the appended claims.

Claims

1. An apparatus for the deployment and retrieval of an unmanned aerial vehicle, the apparatus comprising:

an unmanned aerial vehicle comprising a body having a mounting arrangement and an envelope attached to the mounting arrangement, wherein the envelope defines an internal gas chamber configured to be inflated with gas from a gas source and configured to be deflated; and a capsule defining an internal chamber for receiving the unmanned aerial vehicle therein and comprising: an engagement arrangement for releasably mounting the unmanned aerial vehicle within the capsule; and an opening intended to be uppermost in use and configured such that the unmanned aerial vehicle is able to pass through said opening;

wherein the capsule comprises a retrieval arrangement configured such that, when the unmanned aerial vehicle is mounted in the capsule, movement of the body with respect to the capsule retracts the envelope into the capsule chamber.

2. An apparatus according to claim 1, wherein the unmanned aerial vehicle and the capsule comprise complementary alignment features for aligning the body of the unmanned aerial vehicle substantially centrally within the opening.

3. An apparatus according to claim 2, wherein the opening defines a perimeter, and at least a portion of said perimeter defines a curved profile configured to conform to a portion of the unmanned aerial vehicle.

4. An apparatus according to claim 3, wherein the curved profile is configured to conform to a portion of an underside of the envelope, when the envelope is inflated with a gas.

5. An apparatus according to any preceding claim, wherein the engagement arrangement rotatably mounts the unmanned aerial vehicle within the capsule.

6. An apparatus according to any preceding claim, wherein the body is substantially tubular.

7. An apparatus according to claim 6, wherein the tubular body comprises an enlarged region of increased diameter, wherein the mounting arrangement is provided on said enlarged region.

8. An apparatus according to claim 6 or claim 7, wherein the tubular body defines an axis, and wherein the enlarged region is positioned substantially centrally along said axis.

9. An apparatus according to claim 7 or claim 8, wherein the tubular body comprises shoulder regions at opposing ends of the enlarged region, and wherein said shoulder regions are curved or inclined.

10. An apparatus according to any preceding claim, wherein the opening defines a cross-sectional profile having opposing end regions, and wherein the opposing end regions are curved or angled in a direction away from the body, when the body is received within the chamber.

11. An apparatus according to any preceding claim, wherein the engagement arrangement is configured to position the body substantially centrally within the capsule.

12. An apparatus according to claim 11, wherein the engagement arrangement comprises opposing articulated members configured for receiving an end of the body therebetween.

13. An apparatus according to any preceding claim, wherein the capsule is substantially tubular.

14. An apparatus according to claim 13, wherein the tubular capsule defines a maximum diameter of between approximately 2-10 (5-25cm), preferably in the region of 4-8 (10-20cm), for example 6 (15cm).

15. An apparatus according to any preceding claim, wherein the unmanned aerial vehicle comprises a propulsion arrangement configured to propel the unmanned aerial vehicle, when the balloon is inflated.

16. An apparatus according to any preceding claim, further comprising a drive member, e.g. a drive shaft, for rotating the unmanned aerial vehicle within the capsule.

17. An apparatus according to any preceding claim, wherein the drive member is configured for connecting the unmanned aerial vehicle to a gas source for selectively inflating the envelope with a gas that is lighter than air, and for deflating the envelope.

18. An apparatus according to any preceding claim, wherein the capsule comprises an ejection device configured to disengage the unmanned aerial vehicle from the engagement arrangement prior to deployment.

19. An apparatus according to claim 18, wherein the ejection device is configured to position the body substantially centrally within the opening.

20. A delivery system for an unmanned aerial vehicle, the system comprising:

an apparatus according to any preceding claim; and a delivery tube configured for extending through an aperture in a wall structure;

wherein the delivery tube comprises an opening intended to uppermost in use, and wherein the delivery tube is configured for receiving the apparatus at an end thereof; and wherein the delivery system comprises a positioning arrangement for positioning the capsule opening within a perimeter of the delivery tube opening.

21. A system according to claim 20, wherein the delivery tube and capsule are substantially tubular, preferably wherein the tubular capsule defines a maximum diameter of between approximately 2-10, preferably in the region of 4-8, for example 6

22. An unmanned aerial vehicle comprising:

a body having a mounting platform; and an envelope attached to the mounting platform, wherein the envelope defines an internal gas chamber configured to be inflated with gas from a gas source and configured to be deflated; and wherein the capsule further comprises an engagement arrangement for releasably mounting the unmanned aerial vehicle within a capsule, and wherein the envelope is configured to wrap around the body, when deflated.

23. A capsule for receiving an unmanned aerial vehicle, the capsule comprising:

an internal chamber for receiving an unmanned aerial vehicle therein;

an opening intended to be uppermost in use and configured such that an unmanned aerial vehicle is able to pass therethrough;

an engagement arrangement for releasably mounting an unmanned aerial vehicle within the capsule; and a retrieval arrangement configured such that, when an unmanned aerial vehicle is mounted in the capsule, the retrieval arrangement is configured to move said unmanned aerial vehicle with respect to the capsule in order to retract an envelope of an unmanned aerial vehicle into the chamber.

24. A method of use of the apparatus according to any of claims 1 to 19, the method comprising the steps of:

a) inflating the envelope with a gas from a gas source;

b) disconnecting the unmanned aerial vehicle from the gas source;

c) disengaging the unmanned aerial vehicle from the engagement arrangement; and

d) propelling the unmanned aerial vehicle away from the capsule.

25. A method of use of the apparatus according to any of claims 1 to 19 for retrieval of the unmanned aerial vehicle, the method comprising the steps of:

a) receiving the unmanned aerial vehicle within the capsule via the opening;

b) mounting the unmanned aerial vehicle to the capsule with the engagement arrangement;

c) deflating the envelope; and

d) moving the body within the capsule such that the envelope is retracted into the capsule chamber.