THIS I NVENTION relates to administration of substances to animals. In particular, the invention relates to a substance administration payload for an unmanned aerial vehicle, to a system for administration of substances to animals, and to a method of administering a substance to an animal. Conventionally much of game capturing and the treatment or prevention of diseases affecting game, such as rabies, is done by darting. In many instances a helicopter is utilized, enabling quick aerial tracking down of game and the subsequent darting of the game. This exercise requires an experienced helicopter pilot and in some instances a veterinarian.

Some of the disadvantages of using a helicopter include:

site establishment costs and the logistics of fuelling or renting the helicopter make this option very expensive and cumbersome;

some animals exhibit strong reactions to the noise generated by a helicopter which could result in a stampede and animals getting injured or even dying of fatigue;

when continually exposed to this methodology the game become restless, jittery and stressed.

There is thus a need for apparatus, a system or kit and a method to administer substances to animals, in particular to game and feral animals, which ameliorate at least some of the disadvantages of conventional means and methods used for administrating substances to such animals. According to one aspect of the invention, there is provided an unmanned aerial vehicle substance administration payload which includes

a mounting configured to mount to an unmanned aerial vehicle capable of hovering; a magazine configured to hold at least one unguided free-fall projectile configured to administer a substance to an animal upon impact with the animal, the magazine being carried by the mounting;

a release mechanism to release said unguided free-fall projectile from the magazine so that the projectile can drop under the force of gravity from the magazine to a target animal directly below the magazine; and

aiming means associated with the magazine to determine whether the magazine is vertically directly above said target animal.

In this specification, the term "magazine" is intended to be interpreted broadly to include any component or structural feature configured or intended to attach to, carry, hold, mount, store, suspend, temporarily restrain or the like an unguided free-fall projectile that is configured to administer a substance to an animal upon impact with the animal, until such time that the unguided free-fall projectile is released from the magazine.

The substance administration payload may thus be characterised in that it carries no propellant, e.g. a source of compressed gas or a chemical substance for the production of pressurised gas.

Typically, the aiming means is also being carried by the mounting. As will be appreciated, when in use it has been determined by means of the aiming means that the magazine is vertically directly above the target animal, any unguided free-fall projectile held by the magazine will also be vertically directly above the target animal so that, when released from the magazine, the unguided free-fall projectile should drop onto the animal.

The mounting may be configured to be mounted to an unmanned aerial vehicle capable of hovering (hereinafter referred to as a UAV) by means of one or more fasteners, e.g. bolts and nuts, or a quick release mechanism. Typically, the mounting is configured to be mounted to a frame or undercarriage of a UAV, or to an underside of a UAV. Preferably, the mounting is in use mounted substantially centrally on the UAV, i.e. substantially vertically in line with a centre of gravity of the UAV.

The mounting may include one or more vibration dampers to reduce transmission of vibrations to the magazine and/or aiming means, from a UAV to which the mounting is in use mounted. The mounting may include an attachment portion configured to be mounted to a

UAV, and a carrier portion configured to carry at least the magazine, and typically also the aiming means. The carrier portion may be displaceable or rotatable relative to the attachment portion about at least one axis of rotation, preferably about at least two axes of rotation that are orthogonal.

The payload, which may be considered to be an accessory for a UAV, may include a stabilizer for the carrier portion. Preferably, the payload includes a stabilizer to stabilize each axis of rotation when the carrier portion is displaceable or rotatable about clearly defined or distinct axes. Typically, the stabilizer and axes of rotation are configured to stabilize the carrier portion about two orthogonal axes to maintain said axes in a horizontal plane. As will be appreciated, this ensures in use that the magazine, when arranged to release an unguided free-fall projectile in a downwards direction which is perpendicular to said horizontal plane, will release or drop the unguided free-fall projectile vertically downwardly. Preferably, the magazine is thus arranged to drop the unguided free-fall projectile so that the projectile follows a path which, in the absence of an external Newtonian force other than gravity, such as wind, has substantially no horizontal component.

The stabilizer may include an electric motor for each axes of rotation. Typically, the substance administration payload then also includes a controller to control the attitude of the carrier portion, e.g. about a roll axis and about a pitch or tilt axis. Typically the controller receives attitude information from a gyroscope. Such stabilizers and their controllers are well- known, frequently being used in camera gimbal systems used for image stabilisation, and the like. The stabilizers are compact and lightweight, possibly making use of brushless motors to adjust attitude about each axes of rotation based on attitude information provide by the gyroscope. However, a disadvantage of a motorized stabilizer is that it requires electrical power for the controller, gyroscope and the electric motor(s) which, when obtained from a battery of a battery-powered UAV to which the payload is in use mounted, reduces the operating time of the UAV. Furthermore, even though lightweight, motorized stabilisers may still be heavier than desired. In one alternative embodiment of the invention, the carrier portion is thus joined to the attachment portion by means of a pivot joint such that the carrier portion is suspended below the attachment portion, with a motion damper (such as a fluid-filled damper, e.g. a liquid-filled damper), acting on the carrier portion to dampen movement of the carrier portion relative to the attachment portion. In this way, when the substance administration payload is stationery, gravity can be used to ensure that the magazine, when arranged to release an unguided free-fall projectile in a downwards direction which is perpendicular to a horizontal plane, will release or drop the projectile vertically downwardly. During or after movement of the substance administration payload, the motion damper, e.g. fluid-filled damper, advantageously dampens any pendulum-like movement of the magazine or of an unguided free-fall projectile held by the magazine, upon stopping of the substance administration payload soon stabilising the magazine and allowing the unguided free-fall projectile to be released to drop towards the earth along a straight, vertical path.

The fluid-filled damper may be filled with a viscous liquid or a gel or the like.

The fluid-filled damper may include a housing filled with said fluid, with the pivot joint being located in a wall of the housing, and with a damping member located within the fluid filled housing being connected to the pivot joint for damped displacement within the fluid- filled housing, the carrier portion of the mounting being attached or attachable to the pivot joint outside the fluid-filled housing to move in a damped fashion together with the damping member.

The housing may define a hemispherical or part hemispherical inner surface concentric with the pivot joint, with the damping member defining a circular outer edge, the damping member being configured and sized such that said circular outer edge follows an imaginary hemispherical or part hemispherical surface when displaced, said imaginary hemispherical or part-hemispherical surface being located inside the hemispherical or part hemispherical inner surface defined by the housing and being concentric with the hemispherical or part hemispherical inner surface defined by the housing, with little clearance between the circular outer edge of the damping member and the hemispherical or part hemispherical inner surface. The attachment portion and/or the carrier portion may be of a synthetic plastics or polymeric material. If desired, the synthetic plastics or polymeric material may include carbon fibre to form a carbon fibre reinforced polymer. The substance administration payload may be configured to administer a substance to an animal using an unguided free-fall projectile which is elongate, e.g. in the form of a dart. The substance administration payload may thus also include an elongate free-fall projectile, e.g. a dart configured to administer a substance to an animal upon impact with the animal.

The magazine may be configured to receive or hold a portion of a shaft of at least one elongate unguided free-fall projectile. In one embodiment of the invention, the magazine defines a bore with at least one open end. The bore may then be dimensioned to receive at least a rear end portion of a shaft, e.g. the shaft of a dart, with a front portion of the shaft and/or a head of the unguided free-fall projectile protruding downwardly from the magazine.

The substance administration payload may be configured to administer a substance to an animal using an unguided free-fall projectile in the form of a fluid-filled bomblet that breaks open on impact. The substance administration payload may thus include a free-fall projectile in the form of a fluid-filled bomblet.

The fluid-filled bomblet may include a frangible or brittle shell holding a fluid, typically a liquid. This is reminiscent of the projectiles fired by paintball guns. If desired or necessary, the fluid-filled bomblet may include a shell piercing element within the shell to assist with breaking of the shell upon impact with an animal. As will be appreciated, the fluid-filled bomblet of the substance administration payload is a free-fall projectile, as compared to paintball ammunition which is fired pneumatically, and will thus typically impact an animal at a lower velocity and with less momentum compared to that achieved by a typical paintball gun. A shell piercing element can ensure that the bomblet still breaks open on impact, even considering the lower velocity and momentum of the bomblet.

Instead, or in addition, the shell of the bomblet may be provided with lines of weakness. The magazine may be configured to hold at least one, preferably a plurality of said fluid-filled bomblets configured to break open on impact.

In one embodiment of the invention, the magazine is configured to hold an array, e.g. a linear array, of such fluid-filled bomblets. Typically, when configured to hold one or more fluid-filled bomblets, the magazine has a larger internal diameter, e.g. about a 20 mm diameter, than when configured for the shaft of a dart.

The release mechanism may be remotely controlled. The release mechanism may thus include a receiver to receive a signal, e.g. a radio signal, transmitted from a remote location. Alternatively, the release mechanism may be configured to establish communication with a receiver of the UAV to which the substance administration payload is in use mounted.

The release mechanism may include an actuator operable between a first condition in which an unguided free-fall projectile is prevented from dropping from the magazine, and a second condition in which an unguided free-fall projectile is allowed to drop from the magazine. The actuator may include or may be in the form of a servo employing an electric servomotor.

The release mechanism may include retaining means to retain an unguided free- fall projectile or a portion thereof, e.g. the shaft of a dart, in the magazine. As will be appreciated, there are numerous ways in which the retaining means can retain an unguided free-fall projectile in the magazine, e.g. by way of a friction or by way of interference or even electromagnetically. In one embodiment of the invention, the retaining means is in the form of a pin displaced by the actuator between a disengaged condition in which the pin does not retain an unguided free-fall projectile in the magazine, and an engaged condition in which the pin protrudes into or through a passage in an unguided free-fall projectile to prevent the unguided free-fall projectile from dropping from the magazine.

In another embodiment of the invention, the retaining means is in the form of a closure member displaceable between a position in which an outlet of the magazine is closed, and a position in which the outlet of the magazine is open, allowing an unguided free-fall projectile in the magazine from dropping from the magazine.

The aiming means may include, or may be in the form of an aiming camera and in particular an aiming video camera, e.g. a small analogue or digital video camera. Typically, the aiming camera, e.g. aiming video camera and the magazine are aligned, e.g. in a parallel close side-by-side relationship, such that the aiming camera, e.g. aiming video camera is substantially aimed at a target area that will be impacted by an unguided free-fall projectile released from the magazine, when the path of the projectile is vertically downward, i.e. when the path of the projectile is not influenced by any force, e.g. wind, other than gravity, and when the projectile is not deflected when initially released.

The aiming means may include or define an aiming marker, e.g. a reticle or cross- hair, to indicate a point of impact of an unguided free-fall projectile released from the magazine associated with the aiming means, i.e. essentially to indicate precisely where the aiming camera is aimed at. The aiming marker may be included in a lens of the aiming camera. Instead, the aiming marker may be digitally added to an image provided by the aiming camera. The substance administration payload may include an image transmitter (a so- called On Screen Display or OSD video transmitter) to transmit an image provided by the aiming camera to a remote location. In one embodiment of the invention, the image transmitter is an analogue video transmitter. Alternatively, and possibly preferred, the aiming camera may be configured to communicate with an image or video transmitter of the UAV (a so-called On Screen Display/First Person View or OSD/FPV video transmitter, which is usually an analogue transmitter) to which the substance administration payload is in use attached, so that the image or video transmitter of the UAV can also transmit the aiming camera image or video to a remote location. Typically, such an OSD/FPV video transmitter also transmits flight or navigation data to a remote location.

As indicated hereinbefore, the substance administration payload may include a controller for the one or more stabilizers of the carrier portion, when the carrier portion includes such stabilizers. Typically, when present, the controller is configured to control at least two stabilizers to stabilize the carrier portion about a roll axis and about a pitch axis such that the aiming means in use aims vertically downwardly. The aiming camera may be configured to provide a thermal image. As will be appreciated, a thermal image aiming camera allows locating, and aiming at, an animal in the dark or in conditions of low light. This feature is useful for locating, and aiming at, animals that hide during the day or that remain under cover, e.g. bush or leaf cover during the day, but that move into open areas at night.

Instead, or in addition, the substance administration payload may include a light aiming device, e.g. a laser aiming device or laser pointer, associated with the aiming camera in the sense that the light aiming device throws a light image or light spot at the location that the aiming camera is aimed at. Such a light aiming device can assist with operation of the substance administration payload in low light conditions, e.g. after dark.

The substance administration payload may include a sound generator to generate sound at an intensity higher than that generated by a UAV to which the payload in use is attached. Alternatively, the substance administration payload may be mountable to a UAV carrying such a sound generator. Preferably, the sound generator is remotely activated, e.g. by means of a radio signal, to generate sound electronically. A UAV carrying the substance administration payload can then advantageously be used to chase an animal into an open area so that a substance can be administered to the animal by means of an unguided free-fall projectile released from the magazine of the substance administration payload.

The substance administration payload may include a wind screen for at least the magazine. Advantageously, a wind screen protects the magazine, and hence an unguided free- fall projectile released from the magazine, against turbulence from rotating blades from a UAV carrying the substance administration payload in use. In one embodiment of the invention, the windscreen, open at a bottom end thereof, encircles the mounting and components carried by the mounting, such as the magazine and the aiming means.

The invention extends to an unmanned aerial vehicle capable of hovering, the unmanned aerial vehicle carrying a substance administration payload as hereinbefore described.

According to another aspect of the invention, there is provided a system or kit for administration of substances to animals, the system or kit including

an unmanned aerial vehicle capable of hovering (hereinafter referred to as a UAV), the

UAV carrying, or the UAV being attachable to

a magazine configured to hold at least one unguided free-fall projectile configured to administer a substance to an animal upon impact with the animal;

a release mechanism to release said unguided free-fall projectile from the magazine so that the projectile can drop under the force of gravity from the magazine to a target animal directly below the magazine; and

aiming means associated with the magazine to determine whether the magazine is vertically directly above said target animal. The magazine may be as hereinbefore described.

The release mechanism may be as hereinbefore described.

The aiming means may be as hereinbefore described. The magazine, release mechanism and aiming means may form part of a substance administration payload as hereinbefore described, the substance administration payload being mounted or mountable to the UAV. The UAV may be a multi-rotor UAV, e.g. a quadcopter. Typically, the UAV thus includes a flight controller, preferably a flight controller making use of PID control algorithms. Although the UAV may in principle be autonomous or pre-programmed for an operation or part thereof, so that it can perform the operation or part thereof without further human intervention, it is expected that the UAV will typically be capable of being remotely controlled by a human. Thus, in conventional fashion, the UAV may include or carry a first person view (FPV) video camera and a video transmitter, and the system or kit may include at least one display device, i.e. one or more display devices, to receive and display video images received remotely from the FPV camera (and possibly video images received remotely from the aiming means), and a controller, e.g. a radio controller, to control operation of the UAV. Preferably, the FPV camera and the aiming means are mounted to the UAV on separate mountings, e.g. separate gimbal mountings.

In one embodiment of the invention, the system or kit includes at least two display devices, one display device to receive and display video images from the FPV camera, and one display device to receive and display video images from the aiming means.

In another embodiment of the invention, the video transmitter of the UAV is configured to receive and transmit video images from both the FPV camera and from the aiming means, and said at least one display device displays both images in a split screen fashion. The or each display device may form part of a ground station of the system or kit, the ground station typically including one or more antennae to receive signals from the UAV, and to transmit signals to the UAV.

The UAV may include or carry a GPS module.

The UAV may include a processor programmed or programmable to control the UAV to follow an object by means of image recognition. An example of a UAV that includes a processor that allows the UAV to follow an object is the DJI Phantom 4 quadcopter drone with its Obstacle Avoidance and Active Track features incorporated into its flight controller.

The system or kit may include at least one unguided free-fall projectile configured to administer a substance to an animal upon impact with the animal. Typically, the substance to be administered is a liquid.

In one embodiment of the invention, the unguided free-fall projectile is a dart.

The dart may have a weight of at least about 80 g, preferably at least about 100 g, more preferably at least about 200 g.

Typically, the dart has a weight of less than 900 g.

As will be appreciated, for a given release height, the weight of the dart affects the momentum of the dart at the time of impact with an animal. Depending on the animal, and in particular the toughness or thickness of the animal's hide, it may be necessary to use a heavier dart to ensure that the dart penetrates the hide of the animal, and/or to increase the release height, if possible.

The dart may be configured to administer a substance to an animal in conventional fashion by injecting the substance through the skin of the animal on impact with the animal.

Instead, or in addition, the dart may be configured to administer a substance to an animal by releasing the substance onto the skin of the animal on impact with the animal.

In one embodiment of the invention, the unguided free-fall projectile is a fluid- filled bomblet as hereinbefore described.

The system or kit may include a launch platform for the UAV. The launch platform may be in the form of a raised support defining an aperture or recess through or into which an elongate unguided free-fall projectile, such as a dart, can project downwardly when the UAV is supported on the raised support.

The UAV may include a GPS antenna.

The UAV may include an antenna for the video transmitter of the FPV camera, and to receive control signals from a remote controller.

The UAV may include an antenna for the image transmitter of the aiming means. The system or kit typically includes a remote control device, e.g. a remote multichannel radio frequency transmitter, by means of which a human operator can control or pilot the UAV, and activate the release mechanism to release an unguided free-fall projectile. Preferably, the UAV is a battery-powered UAV using electric motors to drive rotors, e.g. a UAV powered by one or more lithium-ion polymer batteries.

According to another aspect of the invention, there is provided a method of administering a substance to an animal, the method including

positioning an unmanned aerial vehicle capable of hovering (hereinafter referred to as a

UAV) vertically directly above said animal; and

releasing an unguided free-fall projectile configured to administer said substance to said animal upon impact with the animal from the UAV, the projectile being released from a height sufficient to allow the projectile to impact the animal with sufficient momentum to administer said substance to the animal.

The UAV may be as hereinbefore described.

The unguided free-fall projectile may be as hereinbefore described.

The unguided free-fall projectile may be released from a height above the animal, taking into account the weight of the unguided free-fall projectile, so that the unguided free-fall projectile impacts the animal with a momentum of at least about 1.4 kg.m.s ¹ , preferably at least about 1.6 kg.m.s ¹ , more preferably at least about 1.9 kg.m.s ¹ , most preferably at least about 2.5 kg.m.s ^-1 . Typically, the unguided free-fall projectile is released from a height above the animal, taking into account the weight of the unguided free-fall projectile, so that the unguided free-fall projectile impacts the animal with a momentum of no more than about 31 kg.m.s ^_1 , preferably less than about 28 kg.rn.s ^-1 , e.g. between about 18 kg.m.s ¹ and about 22 kg.m.s ¹ . The lower momentum values are appropriate for smaller animals or animals with hides that are relatively thin or less tough, whereas the higher momentum values are appropriate for larger animals or animals with hides that are relatively thick or tougher.

Typically, the unguided free-fall projectile is released from a height above ground of between about 15 m and about 60 m, preferably between about 20 m and about 50 m, more preferably between about 25 m and about 45 m, e.g. between about 30 m and about 35 m.

Positioning the UAV vertically directly above said animal may include receiving a video image from the aiming means, and adjusting the position of the UAV until the UAV is vertically directly above said animal according to said video image.

Adjusting the position of the UAV may be accomplished from a location remote from the UAV, e.g. using a remote radio control transmitter. Although in principle it is possible for the UAV to be configured or programmed to position itself automatically vertically directly above an animal, e.g. by using image recognition and an onboard flight controller, it is expected that the UAV will typically be positioned under the remote control of a human.

The unguided free-fall projectile may be released from a location remote from the UAV, e.g. using said remote radio control transmitter. The method typically includes flying the UAV from a position remote from said animal, to a position in the vicinity of said animal, using the FPV camera of the UAV, a display device to display video images received from said FPV camera, and a radio controlled transmitter operated by a human operator to control the flight of the UAV.

Typically, the method includes hovering the UAV vertically directly above said animal. It is thus an advantage if the UAV includes a GPS module and is configured automatically to hold its position when instructed to do so.

It may also be necessary to follow said animal for a period of time before the unguided free-fall projectile can be released, e.g. if the animal is moving under broken cover, such as scattered trees. It is thus also an advantage if the UAV is capable of following an object, such as an animal, automatically once the object has been identified to the UAV. Typically, such UAV's use a processor programmed for image recognition. The method may thus include instructing the UAV to follow a target animal automatically, before the projectile is released.

The method may include chasing said animal with the UAV from a location which is not suitable for releasing the unguided free-fall projectile at the animal, to a location which is suitable for releasing the unguided free-fall projectile at the animal.

Chasing said animal with the UAV may include activating a sound generator carried by the UAV. The sound generator may be as hereinbefore described.

The method may include launching the UAV from a launch platform. The launch platform may be as hereinbefore described.

The invention will now be described, by way of example only, with reference to the accompanying diagrammatic drawings in which Figure 1 shows a three-dimensional view of one embodiment of an unmanned aerial vehicle substance administration payload, in accordance with the invention;

Figure 2 shows a side view of the substance administration payload of Figure 1;

Figure 3 shows a three-dimensional view of another embodiment of an unmanned aerial vehicle substance administration payload, in accordance with the invention, the substance administration payload including a stabilizer in the form of a fluid-filled damper;

Figure 4 shows a sectional view of the fluid-filled damper shown in Figure 3 of the drawings;

Figure 5 shows yet a further embodiment of an unmanned aerial vehicle substance administration payload, in accordance with the invention, including a stabilizer in the form of a fluid-filled damper different from the fluid-filled damper shown in Figures 3 and 4 of the drawings;

Figure 6 shows a three-dimensional view of one embodiment of a magazine of an unmanned aerial vehicle substance administration payload, in accordance with the invention, together with part of a release mechanism;

Figures 7 to 11 show various views of an unmanned aerial vehicle capable of hovering, in accordance with the invention, the unmanned aerial vehicle carrying the substance administration payload of Figures 1 and 2;

Figures 12 to 16 show various views of an unmanned aerial vehicle capable of hovering in accordance with the invention, the unmanned aerial vehicle carrying the substance administration payload of Figure3;

Figure 17 shows a system or kit in accordance with the invention for administration of substances to animals, in use; and

Figure 18 shows a side view of an unmanned aerial vehicle capable of hovering in accordance with the invention, carrying the substance administration payload of Figures 1 and 2, positioned on a launch platform forming part of the system or kit shown in Figure 17. Referring to Figures 1 and 2 of the drawings, reference numeral 10 generally indicates an unmanned aerial vehicle substance administration payload, or unmanned aerial vehicle accessory, in accordance with the invention. The substance administration payload 10 includes a mounting 12 configured to mount to or be attached to an unmanned aerial vehicle capable of hovering (see for example Figures 7 to 11), a magazine 14 configured to hold a single unguided free-fall projectile, in the form of a dart 16, configured to administer a substance to an animal upon impact with the animal, a release mechanism 18 to release the dart 16 from the magazine 14 so that the dart 16 can drop under the force of gravity from the magazine 14 to a target animal directly below the magazine 14, and aiming means in the form of a small downwards facing aiming video camera 20 which is associated with the magazine 14 to determine whether the magazine 14 is vertically directly above a target animal.

In the embodiment of the substance administration payload of the invention shown in Figures 1 and 2 of the drawings, the mounting 12 is in the form of a commercially available 2-axis camera gimbal, namely the Hobbyking Quanum Q-2D Brushless GoPro 3 Gimbal, weighing about 120 g. As will be appreciated, many commercially available camera gimbal mounts are suitable for use as part of the substance administration payload 10 of the invention, desirable features of a suitable gimbal including lightness and stabilization about at least two axes.

The mounting 12 includes an attachment portion 22 configured to be mounted or attached to an unmanned aerial vehicle capable of hovering (hereinafter referred as a UAV) by means of four fasteners (not shown). Typically, the attachment portion 22 is mounted in use to a frame or undercarriage of a UAV, or to an underside of a UAV, more or less centrally on the UAV so that the substance administration payload 10 is substantially vertically in line with a centre of gravity of the UAV.

In the embodiment illustrated in Figures 1 and 2, the mounting 12 includes four rubber vibration dampers 24 to reduce transmission of vibrations from a UAV to the substance administration payload 10, an in particular to the magazine 14 and to the aiming video camera 20.

The mounting 12 includes a carrier portion 26. The carrier portion 26 includes a mounting wall 26.1 to which the magazine 14 and the aiming video camera 20 are mounted. In the embodiment illustrated in Figures 1 and 2, the magazine 14 and the aiming video camera 20 are sandwiched between two face plates 21 bolted together by means of four threaded shafts and eight nuts, with the shafts passing through the mounting wall 26.1 and with the magazine 14 and the aiming video camera 20 being positioned on opposite sides of the mounting wall 26.1. For calibration purposes, i.e. to ensure that the dart 16 will in use impact a point at which the aiming video camera 20 is aimed at, the position of at least one of the aiming video camera 20 and the magazine 14 is adjustable.

The carrier portion 26, and in particular the mounting wall 26.1, is displaceable or rotatable relative to the attachment portion 22, and hence also relative to a UAV to which the substance administration payload 10 is mounted, in use, about two orthogonal axes 28, 30. During use, the axis 28 defines a pitch or tilt axis for the carrier portion 26 and all components attached to the carrier portion 26 or carried by the carrier portion 26, whereas the axis 30 defines a roll axis for the carrier portion 26 and all components carried by the carrier portion 26. The substance administration payload 10 includes a pitch or tilt motor 32 and a roll motor 34 (see Figure 2) respectively to adjust the pitch or tilt attitude of the carrier portion 26 and the roll attitude of the carrier portion 26, relative to the attachment portion 22 so that both axes 28, 30 remain in a horizontal plane. Furthermore, the substance administration payload 10 includes a gyroscope 35 (see Figure 2). A controller 36, in communication with the gyroscope 35 and the motors 32, 34, is provided to control the attitude of the carrier portion 26 about the pitch axis 28 and about the roll axis 30. In the embodiment illustrated in Figures 1 and 2, the motors 32, 34, the gyroscope 35 and the controller 36 are standard components of the Hobbyking Quanum Q-2D Brushless GoPro 3 Gimbal.

The magazine 14, as illustrated in Figures 1 and 2, is configured to receive or hold a portion of a shaft 40 of the dart 16. The magazine 14 is thus simply a length of square tubing of a plastics material, defining a bore 38 which is open-ended and which is dimensioned to receive a rear end portion of a shaft 40 of the dart 16 snugly or at least with little clearance so that the shaft 40 remains aligned with the bore 38 even when the substance administration payload 10 is moving. A front portion of the shaft 40 and a head 42 of the dart 16 thus protrude downwardly from the magazine 14, as can be clearly seen in Figures 1 and 2 of the drawings, when the magazine 14 is in an operative orientation. The release mechanism 18 includes a servo 44 and retaining means in the form of a pin 46. The servo 44 drives the pin 46 forwards and backwards so that the pin either engages the shaft 40 of the dart 16, within the magazine 14, or is free of the shaft 40. The shaft 40 has a small passage (not shown) into which the pin 46 protrudes when the pin 46 is in an engaged condition. Displacement of the pin 46 from its engaged condition to a disengaged condition removes the pin 46 from the passage in the shaft 40, allowing the dart 16 to drop from the magazine 14 under the force of gravity. In the embodiment of the substance administration payload 10 illustrated in Figures 1 and 2, the servo 44 is a commercially available 9 gram E-Flite servo.

Although not shown in the drawings, a rear end of the shaft 40 of the dart 16 has a transverse notch, and a transverse screw is provided extending through an upper end of the bore 38. When the rear end portion of the shaft 40 is inserted into the bore 38 and rotated such that the screw is seated or received inside the transverse notch, the passage in the shaft 40 is aligned with the pin 46. The aiming video camera 20 illustrated in Figures 1 and 2 of the drawings is a

Foxeer Legend 1, 16-megapixel, 1080P, 60 frames per second, high definition digital video camera. As will be appreciated, many commercially available video cameras can be used as the aiming video camera 20, one desirable feature of the aiming camera 20 being a low weight. The Foxeer Legend 1 weighs 49 g. The aiming video camera 20 is mounted against one side of the mounting wall 26.1 of the carrier portion 26 and the magazine 14 is mounted to an opposite side of the mounting wall 26.1 such that the aiming video camera 20 and the magazine 14 are aligned in a parallel, close side-by-side relationship ensuring that the aiming video camera 20 is substantially aimed at a target area that will be impacted by an unguided free-fall projectile, such as the dart 16, released from the magazine 14, when the path of the dart 16 is vertically downward (i.e. not affected by forces other than gravity, such as wind). Typically, the aiming video camera 20 defines an aiming marker in the form of a reticule or cross-hair to indicate a point of impact of the dart 16, i.e. essentially to indicate precisely where the aiming video camera 20 is aimed at, and hence where a dart 16 in the magazine 14 is aimed at. As will be appreciated, the aiming marker may be included in or applied to a lense of the aiming video camera 20. Instead, the aiming marker may be digitally added to an electronic image provided by the aiming video camera 20, e.g. for display on a remote display screen. The substance administration payload 10 may include an image transmitter (a so-called On-Screen Display or OSD video transmitter) to transmit an image provided by the aiming video camera 20 to a remote location, e.g. for display on a remote display screen. In the embodiment illustrated in Figures 1 and 2 of the drawings, the substance administration payload 10 however does not include an image transmitter. In the embodiment illustrated in Figures 1 and 2, the aiming video camera 20 is configured simply to be connected to an image or video transmitter of the UAV to which the substance administration payload 10 is in use mounted, so that the image or video transmitter of the UAV can also transmit the aiming camera image or video to a remote location. As is well-known to those skilled in the art of UAV's or drones, the image or video transmitter of a UAV is typically called an On-Screen Display/First Person View or OSD/FPV video transmitter, and usually the OSD/FPV video transmitter transmits video images from a navigation video camera carried by the UAV, as well as flight or navigation data provided by sensors carried by the UAV, to a remote operator location, particularly in the case of more sophisticated or expensive drones or UAV's. More sophisticated OSD/FPV video transmitters have the capacity to transmit more than one video channel.

The substance administration payload 10 further includes a sound generator 48 mounted to one of the face plates 21. The sound generator 48 is configured electronically to generate a sound at an intensity, or sound pressure level, higher than that generated by the electric motors and rotors of a UAV to which the substance administration payload 10 is in use mounted. The sound generator 48, like the motors 32, 34 is powered by a battery of the UAV to which the substance administration payload 10 is in use mounted and is remotely activated by means of a radio signal. Although not illustrated in the drawings, the substance administration payload 10 may include a wind screen encircling the carrier portion 26 and all components attached to the carrier portion 26. Such a wind screen may be mounted to the attachment portion 22 to depend therefrom. A wind screen can advantageously protect the magazine 14, and hence an unguided free-fall projectile such as the dart 16 released from the magazine 14, against turbulence from the rotating blades of a UAV to which the substance administration payload 10 is in use mounted.

As will be appreciated, electric wires are required for powering of, and providing control signals to, the motors 32, 34, to power the servomotor of the servo 44 and the sound generator 48, to establish communication between the aiming video camera 20 and the OSD/FPV video transmitter of a drone, and the like. For clarity, these wires are not shown in the drawings. Instead of using a camera gimbal mounting that includes motorized gyroscopic controlled stabilizers, which can add unnecessary weight to the substance administration payload of the invention, the substance administration payload of the invention may employ a stabilizer in the form of a fluid-filled damper. One embodiment of such a substance administration payload is illustrated in Figure 3 of the drawings and generally indicated by reference numeral 100. The substance administration payload 100 includes a fluid-filled damper 102. The substance administration payload 100 is in many respects the same as or similar to the substance administration payload 10, and unless otherwise indicated, the same reference numerals are used to indicate the same or similar parts or features. However, unlike the substance administration payload 10 which includes a mounting in the form of a camera gimbal, the substance administration payload 100 makes use of a custom mounting 112 comprising an attachment portion 122 and a carrier portion 126. As can be seen in Figure 4 of the drawings, a leak-free pivot joint 104 connects a member 106 indirectly to the attachment portion 122. The carrier portion 126, and all components attached to the carrier portion 126, is thus suspended below the attachment portion 122, and is free to swivel pendulum-like (within limits allowed by the pivot joint 104) in any direction below the attachment portion 122, by virtue of the pivot joint 104.

The fluid-filled damper 102 incorporates the pivot joint 104 in a floor 105 and further includes a hemispherical housing 108 and a hemispherical damping member 110 located within the housing 108. The damping member 110 is mounted to an end of an extension 107 of the member 106 which passes in a fluid-tight manner through the pivot joint 104. The damping member 110 defines a circular lower outer edge 111 displaced a small distance from an inner surface of the housing 108. The inner surface of the housing 108 is concentric with the pivot joint 104 and the way in which the damping member 110 is shaped and mounted to the extension 107 ensures that the circular outer edge of the damping member 110 follows an imaginary hemispherical surface, spaced from the hemispherical inner surface of the housing 108, when the extension 107 is displaced, i.e. pivots by means of the pivot joint 104. The imaginary hemispherical surface is also concentric with the hemispherical inner surface of the housing 108. An O-ring 112 is provided on the circular outer edge of the damping member 110 further to restrict clearance between the circular outer edge 111 of the damping member 110 and the hemispherical inner surface of the housing 108. The entire inner volume defined by the housing 108 and the floor 105 is filled with a viscous fluid or gel.

Provided the combined centre of gravity of all components attached to the member 106 is vertically below the member 106, i.e. vertically below the pivot joint 104, the magazine 14 and the aiming video camera 20 attached to the carrier portion 126 will point straight downwards. Displacement of the substance administration payload 100, e.g. when attached to a moving UAV, will cause the carrier portion 126 to move around relative to the attachment portion 122. However, when the substance administration payload 100 comes to a rest, e.g. when the UAV stops to hover, any pendulum-like movement of the carrier portion 126 and components attached thereto will be damped by the fluid-filled damper 102, soon bringing the carrier portion 126 to a rest position relative to the attachment portion 122.

In order to balance the carrier portion 126 and all components attached thereto properly, it may be necessary to rearrange the position of components, such as the aiming video camera 20 or the magazine 14, or to add balancing weights.

Referring to Figure 5 of the drawings, yet another embodiment of a substance administration payload is illustrated and generally indicated by reference numeral 200. The substance administration payload 200 is only shown schematically without similar detail to the detail shown in Figures 1 to 3 of the drawings, the purpose merely being to illustrate another embodiment of a fluid-filled damper, indicated by reference numeral 202. The fluid-filled damper 202 is of an even more simple construction than the fluid-filled damper 102, merely comprising a housing 208 which is filled with a viscous fluid, a pivot joint 204, and a member 206 to which four vanes 211, located within the housing 208, are attached. The vanes 211 provide a large surface area which resists displacement within the fluid-filled housing 208, providing a simple damper for movement of any components attached to the member 206.

The member 206 also defines a displaceable carrier portion 226 of a mounting 212 which also includes an attachment portion 222. Furthermore, a bottom portion of the member 206 defines a magazine 214 to which a dart 16 is releasably attached by a release mechanism 218. An aiming video camera 220 is attached to the member 206/carrier portion 226.

The dart 16 shown in the drawings may be a conventional dart used for darting animals. If desired however, the dart 16 may be weighted to ensure that the dart has sufficient momentum, when released from a practical height of say 15 to 60 metres above an animal, to penetrate the skin of the animal and to release a substance carried by the dart 16 into the animal. Various release mechanisms to inject a substance from a dart into an animal, or to apply such a substance from a dart onto the skin of an animal, are known and in use in commercially available darts and such release mechanisms are thus not further discussed herein.

It may be desirable to use the substance administration payload of the invention to administer a substance to the exterior of an animal (e.g. the hide of an animal), rather than to inject the substance into the animal, without penetrating the skin of the animal. The unguided free-fall projectile of the substance administration payload may thus be in the form of a fluid-filled bomblet that breaks open on impact, preferably only when impacting with momentum above a specified minimum momentum. Referring to Figure 6 of the drawings, reference numeral 60 indicates a plurality of such fluid-filled bomblets. The bomblets 60 are retained in the magazine 14, which is sized to accommodate the bomblets 60. The bomblets 60 are arranged one above the other in a linear array in the magazine 14.

In the embodiment illustrated in Figure 6 of the drawings, the release mechanism 18 includes an apertured disc 62 below a bottom open outlet of the magazine 14. The disc 62 is arranged to rotate and defines a plurality of circumferentially spaced apertures 64. The apertures 64 are large enough so that a bomblet 60 can pass therethrough. Thus, in order to release a bomblet 60 from the magazine 14, the disc 62 is commanded to move to position one of the apertures 64 below the magazine 14 (e.g. by means of a radio-controlled electric motor), allowing one of the bomblets 60 to drop from the magazine 14. Further displacement of the disc 62 then again blocks the outlet of the magazine 14, preventing further bomblets 60 from falling from the magazine 14.

As illustrated in Figure 6 of the drawings, each fluid-filled bomblet 60 includes an internal shell piercing element 66. The purpose of the shell piercing element 66 is to ensure that the bomblet 60 breaks open on impact, even considering the relatively low velocity and momentum of a bomblet 60 released from a height of say 15 to 60 metres above an animal.

An unmanned aerial vehicle capable of hovering (a UAV) carrying a substance administration payload 10, in accordance with the invention, is shown in Figures 7 to 11 of the drawings. The UAV of the invention shown in Figures 7 to 11 is a generic multirotor (quadcopter) radio-controlled UAV or drone 300 with a fixed First Person View (FPV) video camera 302 and a flight controller 304 which also functions as an On Screen Display/First Person View (OSD/FPV) video transmitter. Typically, a UAV carrying a substance administration payload, in accordance with the invention, will however be a more sophisticated radio- controlled drone. For proof of concept purposes, the substance administration payload 10 was in fact mounted to a Storm Drone Antigravity GPS Flying Platform with a 22.2V 4200mah (93.2Wh) Li-Po battery and Tarot 15555 High Strength Foldable propellers. This is a 640 class quadcopter drone. The Storm Drone Antigravity GPS Flying Platform was equipped with a NAZA-M V2 flight controller with a GPS module. The Storm Drone Antigravity GPS Flying Platform carried a Lumenier TX5G Pro 600mW 5.8GHz 32 channel FPV video transmitter and was fitted with an IBCrazy 5.8 GHz LHCP (left hand circularly polarised) Airblade antenna and an IBCRazy 5.8 GHz RHCP (right hand circularly polarised) Blue Beam Ultra antenna. These antennae were used to transmit video images to two separate dedicated remote display devices. A GoPro Hero 3 forward facing First Person View video camera or tracking camera was used on a DJI Zenmuse H3-3D (3-axis) gimbal. The NAZA-M V2 flight controller has a built-in gimbal stabilization function, allowing it to stabilize the DJI Zenmuse H3-3D gimbal/GoPro Hero 3 video camera. The On Screen Display used for flight and navigation purposes was a DJI iOSD mini. The Storm Drone Antigravity GPS Flying Platform was fitted with a Radiolink R9D 9- Channel Receiver configured to communicate using 2.4 GHz Direct Sequence Spread Spectrum technology with a Radiolink AT9 9-channel transmitter or radio-controller. Figures 12 to 16 illustrate the same generic UAV 300 shown in Figures 7 - 11, but this time carrying the substance administration payload 100 shown in Figure 3 of the drawings.

Referring to Figure 17 of the drawings, a system or kit in accordance with the invention for administration of substances to animals, in use, is generally indicated by reference numeral 400. The system 400 includes an unmanned aerial vehicle capable of hovering (a UAV), indicated by reference numeral 300. The same UAV 300 as is illustrated in Figures 7 to 16 are also illustrated in Figure 17, although a more sophisticated UAV will in practice be preferred. The system 400 includes a magazine 14 configured to hold at least one unguided free-fall projectile, in the form of a dart 16, configured to administer a substance to an animal upon impact with the animal, a release mechanism 18 to release the dart 16 from the magazine 14 so that the dart 16 can drop under the force of gravity from the magazine 14 to a target animal, indicated by reference numeral 402, directly below the magazine 14, and aiming means in the form of an aiming video camera 20 associated with the magazine 14 to determine whether the magazine 14 is vertically directly above the target animal 402. In the embodiment illustrated in Figure 17, the magazine 14, release mechanism 18 and aiming video camera 20 all form part of the substance administration payload 10 as hereinbefore described, with the UAV 300 thus carrying the substance administration payload 10. The system 400 further includes a multi-channel radio controller or transmitter

404, a pair of display devices or screens 406, 408 (Lumenier 10.1 inch High Definition First Person View Liquid Crystal Display Monitors that are LED backlit) and a launch platform 410 for the UAV 300. If desired, a single split screen, rather than two dedicated display devices 406, 408, can be used to display images from both video cameras 302, 20.

The display devices 406, 408 form part of a ground station which includes one or more antennae (not shown) to receive signals from the UAV 300.

Typically, the UAV 300 is launched from the launch platform 410. As can be clearly seen in Figure 18 of the drawings, the launch platform 410 defines a raised platform 412 supporting an undercarriage 306 of the UAV 300 to be launched, and defines a recess 414 into which the dart 16, when received in the magazine 14, can project downwardly.

In order to administer a substance to an animal, such as the animal 402 shown in Figure 17 of the drawings, which is an eland antelope, the UAV 300 is flown in conventional fashion by a human operator using the radio controller 404. Typically, the drone 300 can be flown at a speed of up to about 80 km/h, within a control range of up to about 1.5 km. The First Person View video camera 302 is used to navigate the UAV 300 and to locate and identify the animal 402, whereafter the operator positions the UAV 300 vertically directly above the animal 402. In order to ensure that the UAV 300, and hence the substance administration payload 10, is vertically directly above the animal 402, the aiming video camera 20 of the substance administration payload 10 is used. Images from the aiming video camera 20 are transmitted from the UAV 300 to the display 406, whereas images from the First Person View or navigation video camera 302 are transmitted to the display 408. When the operator has determined by means of the aiming video camera 20 and the image on the display screen 406, which also generates a cross-hair image calibrated to indicate the point of impact of the dart 16 when released from the magazine 14, that the substance administration payload 10 is directly vertically above the animal 402, the radio controller 404 is used to send a signal to the UAV 300 to release the dart 16. The servo 44 is thus activated by means of a radio signal, retracting the pin 46 thus allowing the dart 16 to drop under the force of gravity from the magazine 14. Typically, the dart 16 is released from a height of between about 15 m and about 60 m above the animal 402, often at a height of about 30 m to 35 m, at which height many animals still tolerate the proximity of the hovering UAV 300.

When the dart 16 impacts the animal 402 with sufficient momentum, the substance carried by the dart 16, e.g. a vaccine, drug or tranquilizer, is administered to the animal in conventional fashion, e.g. by injection into the animal or by release onto the skin of the animal.

If desired, the GPS location of the animal 402 is recorded by means of the GPS module of the flight controller of the UAV 300, before the UAV 300 is flown back to the launching platform 410 at the ground station.

If case it is necessary to follow the animal 402 for some time, before the dart 16 can be released onto the animal 402, it is convenient if the UAV 300 is capable of following the animal 402 automatically once the animal 402 has been identified by the operator to the UAV 300. This is another reason why the UAV 300 should be a sophisticated, up-market UAV and not a basic, more affordable UAV. The DJI Phantom 4 drone for example has a feature called Active Track which allows an object to be automatically tracked by the drone.

It may in practice also be necessary to hover the UAV 300 above the animal 402 for some time. A UAV with an accurate position hold function, which requires a GPS module, is thus typically preferred.

It may also be necessary to chase the animal 402 with the UAV 300 from a location which is not suitable for releasing the dart 16 at the animal 402, to a location which is more suitable for releasing the dart 16 at the animal 402. This can be achieved by activating the sound generator 48 remotely using the radio controller 404. Surprisingly, the inventors have found that most animals do not respond to the noise generated by a UAV such as a quadcopter and thus that it is necessary to generate more noise if it is desired to chase an animal such as an antelope in a particular direction. One exception to this general observation is the wildebeest, which does seem to take notice of a quadcopter UAV and which one should thus be able to chase without making use of a sound generator carried by the substance administration payload 10 or by the UAV 300.

If the purpose of the dart 16 is to tranquilise the animal 402, a ground team is despatched to the GPS location provided by the UAV as soon as the animal 402 has been darted.

The invention, as illustrated, provides an unmanned aerial vehicle substance administration payload or accessory, an unmanned aerial vehicle capable of hovering which carries such a substance administration payload, a system or kit for administration of substances to animals and a method of administering a substance to an animal which can be employed to administer substances to animals, in particular to game and feral animals. The equipment and method of the invention, as illustrated, ameliorate at least some of the disadvantages of conventional means and methods used for administering substances to such animals. In particular, capital costs and operating costs associated with the substance administration payload and the unmanned aerial vehicle of the invention are orders of magnitude less when compared to the use of a helicopter carrying a person darting animals with a pneumatic dart gun. Furthermore, much less noise is generated by the UAV, as illustrated, compared to the noise generated by a helicopter, leading to the animals being much less stressed.

In some embodiments of the invention, the unmanned aerial vehicle substance administration payload can carry a plurality of unguided free-fall projectiles, such as fluid-filled bomblets. This is an advantage, taking into account the limited operating time most battery operated drones have and the distances that the drone often has to travel from its base station to where animals are to be found and targeted. With a plurality of unguided free-fall projectiles being available, a plurality of animals can be targeted on a single flight.

Using an unguided free-fall projectile, rather than a propelled projectile (e.g. a pneumatically propelled projectile) also provides advantages. A payload configured to deliver an unguided free-fall projectile is likely to be lighter, less complicated and less expensive than a payload configured to propel a projectile at an animal. A lighter payload will increase the range and operating time of the drone carrying the payload. Aiming of an unguided free-fall projectile is also likely to be less complicated than aiming of a propelled projectile, particularly over longer distances. As gravity does not influence the path of a free-fall projectile, a free-fall projectile is likely to be able to be released from a larger distance (height) from an animal, e.g. more than 30 meters above the animal and still be accurate, compared to the distance over which projectile can be propelled which has a flight path with a horizontal component.

The accuracy of pneumatically propelled projectiles will also be dependent on the accurate control of pressure of the air which is used to propel the projectiles, which is not the case for a free-fall projectile. In addition, a pneumatically propelled projectile requires a barrel of significant length to ensure accuracy over practical distances, rendering the payload unwieldy and increasing its weight. Loading a pneumatically propelled projectile into a barrel and readying the equipment for firing or discharging would also be more complicated and time consuming than loading a magazine with a free-fall projectile, as a small, limited capacity (and hence limited weight) pressurised air supply carried by a drone fitted with a barrel for a pneumatic dart would typically have to be re-pressurised from a large, heavy supply of pressurised air before each flight.