Field of the invention

The invention generally relates to a system for management of secondary vehicles to transit a rail tunnel, and in particular to a system for managing transit of UAVs through rail tunnels.

Background to the invention

Unmanned aerial vehicles (UAVs) comprise a variety of vehicles, from conventional fixed wing airplanes, to helicopters, and are used in a variety of roles. They can be remotely piloted by a pilot on the ground or can be autonomous or semi-autonomous vehicles that fly missions using pre-programmed coordinates, global positioning system (GPS) navigation, etc. UAVs also include remote control helicopters and airplanes used by hobbyists.

UAVs can be equipped with cameras to provide imagery during flight, which may be used for navigational or other purposes (e.g., to identify an address). UAVs can also be equipped with sensors to provide local weather and atmospheric conditions, and other conditions. UAVs can also include cargo bays, hooks, or other means for carrying payloads.

Newer generation UAVs can also provide significant payload capabilities. As a result, UAVs can also be used for delivering packages, groceries, mail, and other items. The use of UAVs for deliveries can reduce costs and increase speed and accuracy.

With UAV flight efficiency improving rapidly as power technology improves, UAVs are being integrated into logistics networks and for delivery of cargo over increasing distances.

However, UAVs are often still affected by extreme environmental conditions and are, for example, unsuitable for use in high winds. This makes their use over mountainous regions, for example, of limited use.

It is an object of the present invention to go at least some way toward improving the performance of UAVs in areas where environmental conditions may be hazardous for UAV use, or which at least provides the public with a useful choice. Other objects of the invention may become apparent from the following description which is given by way of example only.

In this specification, where reference has been made to external sources of information, including patent specifications and other documents, this is generally for the purpose of providing a context for discussing the features of the present invention. Unless stated otherwise, reference to such sources of information is not to be construed, in any jurisdiction, as an admission that such sources of information are prior art or form part of the common general knowledge in the art.

Summary of the invention

In a first broad aspect, the invention broadly consists in a system configured to control thoroughfare of a UAV through a tunnel shared by primary vehicle traffic, the system comprising: a controller configured to interface with: a UAV; a primary vehicle data system; and wherein the controller is configured to: output navigation data to the UAV so as to cause the UAV to navigate to the tunnel; control operation of the UAV through the tunnel.

In some embodiments, the system further comprises a transit vehicle adapted for ground transportation of the UAV, and the controller is configured to output a signal to the transit vehicle to thereby control operation of the UAV through the tunnel.

In some embodiments, the controller is configured to determine a tunnel for use as part of a UAV navigation path.

In some embodiments, the controller is configured to output data operable by the UAV as a navigation flight path, the flight path including the tunnel as a navigation point.

In some embodiments, the controller is configured to receive a signal indicative of the UAV be attached or otherwise ready for transportation by the transit vehicle.

In some embodiments, the controller is configured to determine the direction of any vehicle approaching a tunnel comprising a thoroughfare shared by a transit vehicle.

In some embodiments, the controller is configured to determine the desired direction of travel of the transit vehicle through the tunnel from the UAV navigation data by determining a point of tunnel entry as a first encountered point in the navigation path.

In some embodiments, the controller is configured to receive a signal indicative of the direction of travel of the primary vehicle traffic.

In some embodiments, the controller is configured compare the direction of travel through the tunnel of the primary vehicle traffic to the desired direction of travel of the transit vehicle, and when the direction of travel of the vehicle approaching the tunnel is opposite that of the transit vehicle: determine a time until the approaching vehicle reaches a tunnel end where the vehicle will enter the tunnel and the transit vehicle will exit the tunnel, determine a time required by the transit vehicle to travel through the tunnel, and determine the time required by the transit vehicle to travel through the tunnel is greater than the time until the

approaching vehicle reaches a tunnel end where the vehicle will enter the tunnel;

In some embodiments, the controller is configured compare the direction of travel through the tunnel of the primary vehicle traffic to the desired direction of travel of the transit vehicle, and when the direction of travel of the vehicle approaching the tunnel is the same as that of the transit vehicle: determine a time until the approaching vehicle reaches a tunnel end where the vehicle will exit the tunnel and the transit vehicle will exit the tunnel, and determine the time required by the transit vehicle to travel through the tunnel is greater than the time until the approaching vehicle reaches a tunnel end where the vehicle will exit the tunnel; and output a signal operable to send the transit vehicle through the tunnel when the tunnel is determined as available for use.

In some embodiments, the controller is configured to determine the transit vehicle has travelled through the tunnel; then output a signal to cause re-launch of the UAV to resume the navigation path.

In some embodiments, the controller is configured to determine receive weather data comprising one or more data items indicative of adverse weather; compare the one or more data items to a threshold, and output a signal operable to divert the UAV from a first flight plan to a second flight plan including use of the tunnel.

In some embodiments, the controller is configured to determine whether use of the tunnel by the UAV would avoid the adverse weather conditions.

In some embodiments, the controller is configured to determine a safe tunnel traversal window from a first time required for the transit vehicle to safely travel from one tunnel end to the other, including any a safety time buffer.

In some embodiments, the first time is typically predetermined and may be measured during a testing period; the second time is deduced from traffic information data; and the second time may be deduced from at least location, speed, direction and length information for any given primary vehicle. In some embodiments, the controller is configured to determine the transit vehicle should traverse the tunnel when the first time is less than the second time.

In another broad aspect, the invention consists in a navigation system configured to support flight navigation of a UAV along a flight path including one or more waypoints, wherein the navigation system is configured to: receive information relating to at least one weather condition outside of one or more predetermined UAV operation conditions relating to safe flight; receive information relating to the location of the at least one weather condition and determine whether the at least one weather condition is located on the flight path;

determine use of a tunnel comprising at least a section of the flight path would avoid the at least one weather condition; and modify the flight path such that the tunnel comprises at least one waypoint of the flight path.

In another broad aspect, the invention consists in a system configured to control

thoroughfare of a UAV through a tunnel used by primary vehicle traffic, the system comprising a controller configured to;

interface with the UAV and a primary vehicle data system and receive primary vehicle traffic timing data from the primary vehicle data system;

output navigation data comprising a plurality of waypoints and a plurality of UAV timing events for one or more waypoints, wherein the waypoints define a UAV travel path; and wherein the UAV waypoints comprise a travel path through the tunnel, and the timing events are traffic based on the primary traffic timing data such that the UAV and primary vehicles are operable to share use of the tunnel.

In some embodiments, the system further comprises a ground transit vehicle adapted for ground transportation of the UAV through the tunnel, the ground transit vehicle adapted to transport the UAV through the tunnel.

In some embodiments, the controller is configured to control operation of the ground vehicle and UAV through the tunnel based on the primary vehicle traffic timing data.

In some embodiments, the controller is configured to determine the direction of a primary vehicle approaching the tunnel and the navigation data is based on the determined direction.

In some embodiments, the controller is configured to determine the desired direction of travel of the transit vehicle through the tunnel from the UAV navigation data by determining a point of tunnel entry as a first encountered tunnel end in the navigation path. In some embodiments, the controller is configured compare the direction of travel through the tunnel of the primary vehicle traffic to a desired direction of travel of the UAV through the tunnel, and

when the direction of travel of the vehicle approaching the tunnel is opposite that of the transit vehicle:

determine a time until the approaching vehicle reaches a tunnel end where the vehicle will enter the tunnel and the transit vehicle will exit the tunnel,

determine a time required by the transit vehicle to travel through the tunnel, and

determine the time required by the transit vehicle to travel through the tunnel is greater than the time until the approaching vehicle reaches a tunnel end where the vehicle will enter the tunnel.

In some embodiments, the controller is configured compare the direction of travel through the tunnel of the primary vehicle traffic to the desired direction of travel of the transit vehicle, and

when the direction of travel of the vehicle approaching the tunnel is the same as that of the transit vehicle:

determine a time until the approaching primary vehicle reaches a tunnel end where the vehicle will exit the tunnel and the transit vehicle will exit the tunnel, and

determine the time required by the transit vehicle to travel through the tunnel is greater than the time until the approaching primary vehicle reaches a tunnel end where the vehicle will exit the tunnel; and

output a signal operable to send the transit vehicle through the tunnel when the tunnel is determined as available for use.

In some embodiments, the controller is configured to determine the ground transit vehicle has travelled through the tunnel; then

control re-launch of the UAV to resume the navigation path.

In some embodiments, the controller is further configured to:

determine a first time period required for the transit vehicle to traverse the tunnel, and determine a second time period required for the primary vehicle to traverse the tunnel.

In some embodiments, the first time period includes a buffer time period based on a safety factor. In some embodiments, the second time period is determined from at least location, speed, direction and length information of the primary vehicle.

In some embodiments, the controller is configured to instruct the transit vehicle to traverse the tunnel when the first time is less than the second time.

In another broad aspect, the invention consists in a method of operating a UAV on a navigation path which includes a thoroughfare of a tunnel used by primary vehicle traffic, the method comprising:

determining a desired UAV navigation path,

determining primary vehicle traffic timing data from the primary vehicle data system;

generating navigation data comprising a plurality of waypoints and a plurality of UAV timing events for one or more waypoints, wherein the waypoints define a UAV travel path through the tunnel, and the timing events are traffic based on the primary traffic timing data such that the UAV and primary vehicles are operable to share use of the tunnel.

In some embodiments the method further comprises controlling a ground transit vehicle adapted for ground transportation of the UAV through the tunnel, the control based on the primary vehicle traffic timing data.

In some embodiments the method further comprises comparing the direction of travel through the tunnel of the primary vehicle traffic to a desired direction of travel of the UAV through the tunnel as defined by the navigation path, and, when the direction of travel of the vehicle approaching the tunnel is opposite that of the transit vehicle:

determine a time until the approaching vehicle reaches a tunnel end where the vehicle will enter the tunnel and the transit vehicle will exit the tunnel,

determine a time required by the transit vehicle to travel through the tunnel, and

determine the time required by the transit vehicle to travel through the tunnel is greater than the time until the approaching vehicle reaches a tunnel end where the vehicle will enter the tunnel.

In some embodiments the method further comprises comparing the direction of travel through the tunnel of the primary vehicle traffic to the desired direction of travel of the transit vehicle, and when the direction of travel of the vehicle approaching the tunnel is the same as that of the transit vehicle:

determine a time until the approaching primary vehicle reaches a tunnel end where the vehicle will exit the tunnel and the transit vehicle will exit the tunnel, and determine the time required by the transit vehicle to travel through the tunnel is greater than the time until the approaching primary vehicle reaches a tunnel end where the vehicle will exit the tunnel; and

output a signal operable to send the transit vehicle through the tunnel when the tunnel is determined as available for use.

In some embodiments the method further comprises determining the UAV has traversed the tunnel and controlling launch of the UAV to resume the navigation path.

In another broad aspect the invention relates to any one or more of the above statements in combination with any one or more of any of the other statements.

Other aspects of the invention may become apparent from the following description which is given by way of example only and with reference to the accompanying drawings.

As used herein the term "and/or" means "and" or "or", or both. The term "comprising" as used in this specification and claims means "consisting at least in part of". When interpreting statements in this specification and claims which include that term, the features, prefaced by that term in each statement all need to be present but other features can also be present. Related terms such as "comprise" and "comprised" are to be interpreted in the same manner.

The entire disclosures of all applications, patents and publications, cited above and below, if any, are hereby incorporated by reference. This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more of said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.

To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be in any sense limiting.

Brief description of the drawings The invention can be better understood with reference to the following drawings. The elements of the drawings are not necessarily to scale relative to each other, emphasis instead being placed upon clearly illustrating the principles of the invention. Furthermore, like reference numerals designate corresponding parts throughout the several views.

Figure 1 illustrates a UAV and flight path.

Figure 2 illustrates an example of a UAV 0 which may have a flight path routed through a tunnel which is used primarily for locomotive traffic.

Figure 3 shows a diagram of one exemplary implementation whereby a transit vehicle is provided to facilitate a UAV launch and landing zone, and transportation of a UAV through a tunnel.

Figure 4 shows an overview of exemplary system modules.

Figure 5 outlines an exemplary implementation of the system modules of Figure 4.

Figure 6 is a flow diagram which outlines a control process.

Figure 7 illustrates an exemplary temporal visualisation of temporal event considerations made by the controller module which has determined a train scheduled to enter a tunnel from a direction opposing the direction of intended travel of a transit vehicle.

Figure 8 illustrates an exemplary temporal visualisation of temporal event considerations made by the controller module which has determined a train scheduled to enter a tunnel from the same direction as the direction of intended travel of a transit vehicle.

Detailed description of the invention

Exemplary methods and systems are described herein. It should be understood that the word“exemplary” is used herein to mean“serving as an example, instance, or illustration.” Any embodiment or feature described herein as“exemplary” or“illustrative” is not necessarily to be construed as preferred or advantageous over other embodiments or features. More generally, the embodiments described herein are not meant to be limiting. It will be readily understood that certain aspects of the disclosed systems and methods can be arranged and combined in a wide variety of different configurations, all of which are contemplated herein.

Many of the functional units described in this specification are labelled as modules, in order to more particularly emphasise their implementation independence. For example, a module may be implemented as a hardware circuit specialized circuits, gate arrays, purpose specific semiconductors such as preprogramed for function microprocessors, logic chips, transistors, or other discrete components, or a combination of these components. A module may also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices or other similar devices.

Modules may also be implemented in software for execution by various types of processors. An identified module of executable code may, for instance, comprise one or more physical or logical blocks of computer instructions which may, for instance, be organized as an object, procedure, or function.

Further, a module need not be a single element nor multiple elements physically located together, but may comprise disparate instructions stored in different locations which, when joined logically together, comprise the module and achieve the stated purpose for the module. For example, the system described in this specification includes a UAV which includes flight control system as a first module, and a ground based computer system which interfaces to the UAV. The UAV system and ground based system may form one general flight and navigation control module.

A module of executable code may be a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data may be identified and illustrated herein within modules, and may be embodied in any suitable form and organized within any suitable type of data structure. The operational data may be collected as a single data set, or may be distributed over different locations including over different storage devices, and may exist, at least partially, merely as electronic signals on a system or network. Where a module or portions of a module are implemented in software, the software portions are stored on one or more computer readable storage media.

Any combination of one or more computer readable storage media may be utilised. A computer readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific (non-exhaustive) examples of the computer readable storage medium would include the following: a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a portable compact disc read-only memory (CD-ROM), a digital versatile disc (DVD), a Blu-ray disc, an optical storage device, a magnetic tape, a magnetic disk, a magnetic storage device, integrated circuits, other digital processing apparatus memory devices, or any suitable combination of the foregoing, but would not include propagating signals. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device.

Further, the term network is generally used to describe a means through which data is transported from one location or module to another. In this context, the network may equally include the transportation of data by writing that data to a transportable form of computer readable storage media, and relocating that storage from one physical location to another. Furthermore, the described features, structures, or characteristics of the disclosure may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided, such as examples of programming, software modules, user selections, network transactions, database queries, database structures, hardware modules, hardware circuits, hardware chips, etc., to provide a thorough understanding of embodiments of the disclosure. Flowever, the disclosure may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the disclosure.

The term“unmanned aerial vehicle,” or UAV, as used in this disclosure, refers to any autonomous or semi-autonomous vehicle that is capable of performing some functions without a physically-present human pilot. Examples of flight-related functions may include, but are not limited to, autonomous flight, sensing its environment or operating in the air without a need for input from an operator, among others. Further, embodiments herein are described in relation with aerial vehicles and flight paths. Flowever, these embodiments are equally applicable to land or water based vehicles capable of following a navigable path.

When an unmanned vehicle operates in a remote-control mode, a pilot or driver that is at a remote location can control the unmanned vehicle via commands that are sent to the unmanned vehicle via a communications link. When the unmanned vehicle operates in autonomous mode, the unmanned vehicle typically moves based on pre-programmed navigation waypoints, dynamic automation systems, or a combination of these. Further, some unmanned vehicles can operate in both a remote-control mode and an autonomous mode, and in some instances may do so simultaneously. For instance, a remote pilot or driver may wish to leave navigation to an autonomous system while performing another task such as operating on-board sensors, emitters, or a mechanical system for picking up objects via remote control. Various types of unmanned vehicles exist for various different environments. For example, unmanned vehicles exist for operation in the air, on the ground, on the water, underwater, and in space. Unmanned vehicles also exist for hybrid operations in which multi-environment use is possible. Examples of hybrid unmanned vehicles include an amphibious craft that is capable of operation on land as well as on water or a floatplane that is capable of landing on water as well as on land.

A UAV may be autonomous or semi-autonomous. Some functions could be controlled by a remote human operator, while other functions are carried out autonomously. Further, a UAV may be configured to allow a remote operator to take over functions that can otherwise be controlled autonomously by the UAV. Further, a given type of function may be controlled remotely at one level of abstraction and performed autonomously at another level of abstraction. For example, a remote operator could control high level navigation decisions for a UAV, such as by specifying that the UAV should travel from one location to another (for example, from a launch or loiter position to a premises), while the UAVs navigation system autonomously controls other navigation decisions, such as the specific route to take between the two locations, specific flight controls to achieve the route and avoid obstacles while navigating the route, and so on. Other examples are also possible. A remote operator could also control other aspects of the UAV such as movement of a camera.

A UAV can be of various forms. For example, a UAV may take the form of a rotorcraft such as a helicopter or multirotor, a fixed-wing aircraft, a lighter-than-air aircraft such as a blimp, a tail-sitter aircraft, and/or glider aircraft, among other possibilities. Further, the terms“drone”, “unmanned aerial vehicle system” (“UAVS”), remotely piloted aircraft (“RPA”) or“unmanned aerial system” (“UAS”) may also be used to refer to a UAV.

Figure 1 illustrates a UAV 10 having a flight path 15. Part of that flight path may involve traversal of a mountainous region 20 which involves the UAV climbing to a high altitude 16 to clear the summit 22 of the mountain 20. Mountainous regions are typically subject to high winds 21 which may disrupt UAV flight. Therefore, if there is a tunnel through that mountain, use of that tunnel by the UAV would avoid subjecting the UAV to potentially damaging environmental conditions found above the mountain.

Accordingly, embodiments of the invention relate to the use of UAVs around and through tunnels such a tunnel constructed for the primary purpose of thoroughfare of rail traffic through a landscape. Rail tunnels often exist in mountainous regions where environmental conditionals may unsuitable for regular UAV flight. Therefore there are benefits which may be achieved through use of tunnels by UAVs such as avoiding potentially damaging environmental conditions. However, UAVs are typically fragile and care must be taken to avoid collision with vehicles whom the tunnel is primarily used for. Figure 2 illustrates an example of a UAV 10 which may have a flight path routed through a tunnel 25 which is used primarily for locomotive traffic 30. A tunnel used by rail based traffic for example

necessitates consideration of the times in which a rail tunnel is free for use.

Embodiments of the invention relate to systems and associated methods of operation for managing use of a UAV in a tunnel and in and around primary vehicle tunnel traffic.

Figure 3 shows a diagram of one exemplary implementation whereby a transit vehicle 40 is provided to facilitate a UAV launch and landing zone, and transportation of a UAV through a tunnel 25. The UAV 10 may be configured to land directly on the transit vehicle 40, or the UAV may land at a separate location and be shifted to the transit vehicle. In the example shown, the tunnel comprises a thoroughfare 42 such as road or rail. The transit vehicle is configured to reside near, but not on the thoroughfare 42 such that regular traffic my use the tunnel without regard to for the transit vehicle.

In one exemplary embodiment, the thoroughfare 42 is a rail section which extends through the tunnel 25. The transit vehicle is adapted to follow a first path 41 which directs the transit vehicle onto the rail, follow a second path 42 to travel through the tunnel, then follow a third path 43 to move off the rail once the tunnel has been traversed. To facilitate this

functionality, the transit vehicle may be a rail vehicle which moves into a rail siding, or it may be a vehicle adapted for the hybrid engagement of rail and off-rail use. Ultimately, the transit vehicle is able to be removed from the rail line to a location safely removed from the path of rail vehicles.

An exemplary system 100 comprising modules configured to coordinate thoroughfare of a UAV through a vehicle transportation tunnel are shown in Figure 4. The system 100 has a UAV module 1 10, a transit vehicle module 120, and a vehicle network module 130. Each of these modules may be in direct communication with other modules, or it may provide a conduit for data communication between modules.

The exemplary UAV module 1 10 is primarily tasked with flight operations of the UAV and provide functionality for UAV flight control, navigation, flight power management, launch procedures, landing procedures, launching and landing zones, control and positioning of the UAV when landed, and communication with one or more other modules via wired or wireless interfaces. Further information processed by the UAV module 1 10 is data relating to UAV inventory, UAVs in use, UAV landing areas, UAV payloads, UAV fuel or power status, UAV flight paths, and weather proximate any UAV flight paths.

The exemplary transit vehicle module 120 is tasked with tracking the location of the transit vehicle 40 and this function may be facilitated by conventional technology including satellite navigation, inertial measurement units, gyroscopes, dead reckoning, radio beacons, cellular communication (e.g. 3G, 4G, 5G), Al technology, and visualisation technology.

The exemplary vehicle network module 130 is operable to determine the data relating to the use of the tunnel by primary traffic. Data includes items such as the location of vehicles who are using or intending to use the tunnel, and any scheduled usage of the tunnel.

Figure 5 outlines an exemplary implementation of the system 100 configured for use with a rail tunnel and around rail based tunnel traffic. In the depicted example, the vehicle network module 130 has rail network module 60 which is configured to receive data items 50 relating to trains, such as the location, speed, direction, length, and cargo type. In the present rail tunnel example, integration with a rail network to gather information relating to local rail traffic would present a simple solution. However, the vehicle network module 130 may have an arrangement of sensors configured to sense train data. Further, the vehicle network module 130 may have an arrangement of sensors configured to compliment any data received from a rail network.

In some embodiments, the transit vehicle 40 includes visualisation technology which constitutes camera and image processing technology. In some embodiments, the transit vehicle 40 has an imaging system configured to sense visual indications relating to the thoroughfare to be travelled. In one example, the imaging system is configured to detect the location of railway tracks and determine the position of the transit vehicle relative to the railway tracks. In such applications, the transit vehicle module 120 is configured to control alignment of the transit vehicle on a railway track. For example, where the transit vehicle is a vehicle configured for on-rail and off-rail travel, the transit vehicle module 120 is configured to control the transition of the transit vehicle from an off-rail to an on-rail state, and the imaging system configured to detect alignment of the transit vehicle with a railway.

Further, in some embodiments, the transit vehicle module 120 has pressure sensors configured to detect engagement of the vehicle with a railway line. For example, in such embodiments, the output signal from a pressure sensor is used to determine the nature of the surface the vehicle is located.

A controller module 200 is operably connected to the transit vehicle module 40, the UAV 10 and the vehicle network module. The controller may be integrated with control electronics on board the transit vehicle, or it may be integrated with, for example, a base station. A base station may be desirable in some circumstances to provide local control over a UAV launch and landing site, transportation of the UAV to and from a transit vehicle, and movements of the transit vehicle to and from the tunnel thoroughfare.

For example, in some embodiments, a base station may include a UAV launching and landing zone where mechatronics are configured to engage with and transport any UAV to a transit vehicle. In other embodiments, the transit vehicle is adapted to provide a UAV launch and landing zone such that intermediate transportation of any UAV is not required. In some embodiments, a launch or landing zone may be configured to conduct secondary tasks such as communication with a UAV that the zone is clear for access, charging of a UAV power source, and providing local navigation data to assist with UAV precision landings. The landing zone may optionally provide shelter from environmental conditions and may further act as a relay station or interim destination for any UAV flight path.

The system 100 is intended to support the use of UAVs which form part of a cargo delivery system. UAVs have already shown use for the expedited delivery of cargo and have shown real world advantageous over ground-based delivery methods. For example, UAVs find particular advantages with cargo delivery over hostile terrain, such as forest, bodies of water, wetlands or mountainous regions, and in urban areas where traffic may slow cargo delivery. As part of a cargo delivery system, a UAV will be loaded with cargo and launched into airspace. Once in flight, the UAV will follow a navigation path to a destination where it may land or drop the cargo.

Operation of the system 100 will now be described with reference to the process set out in Figure 6. As outlined above, the first step 300 in the process is for the UAV to take flight and follow a flight path to a destination.

At step 301 , the UAV may receive information relating to adverse weather conditions on the flight path from the controller 200 via a communication network. At step 302, the controller is configured to determine a flight plan which is able to make use of tunnel to avoid

engagement with the adverse weather conditions. At step 303, the controller is configured to determine whether use of the tunnel by the UAV would avoid the adverse weather conditions. For example, by avoiding the location of the adverse weather conditions, or by taking shelter in the tunnel.

To determine adverse weather conditions, the controller is configured to receive weather station data from sensors operable to determine at least one of wind speed or precipitation at a location on the flight path. The controller is configured to compare the weather data to one or more thresholds which relate to predetermined flight capabilities of the UAV on that flight path. For example, a UAV may be capable of flight in wind speeds up to 5 m/s.

Therefore, the controller is configured to compare received flight path wind speed data, compare that data to the UAV threshold, and make a determination of whether the UAV is capable of enduring the flight path. If, for example, wind speed data is above the UAV limit, the controller is configured to determine whether a tunnel is available for in the location of the detected adverse weather condition.

It should be noted that steps 301 to 303 could be omitted in circumstances where the tunnel is always intended to form part of the path between a UAV launch location and a final destination.

At step 304, the controller is configured to instruct the UAV to navigate to the vicinity of tunnel entrance. This instruction may be provided as part of a flight plan originally provided to the UAV, or it may be an instruction communicated to the UAV during execution of its flight plan. This navigation step may include a landing procedure, and a procedure to cause engagement with the transit vehicle.

For example, where the transit vehicle provides a UAV landing platform, the UAV may engage with the transit vehicle simply by landing upon it. Flowever, the UAV may also land on a separate landing platform and require transportation to the transit vehicle. Once positioned on the transit vehicle, a stabilising device or tether is used to secure the UAV during transportation.

The controller is configured to execute step 305 when the UAV is loaded to the transit vehicle. At step 305, the controller is configured to determine whether the tunnel is free for use by the transit vehicle. This determination is deduced from information relating to tunnel traffic. In a rail tunnel example, a tunnel is determined as free for use when there is sufficient time for the transit vehicle to transport the UAV from a first end of the tunnel to a second end. Sufficient time is an accumulation of time required for the transit vehicle to manoeuvre onto the tunnel thoroughfare, traverse the tunnel then manoeuvre off the tunnel thoroughfare to a safe location. The safe location may be a location where the UAV is able to be launched, or where the UAV is able to be offloaded from the transit vehicle for subsequent launch.

The controller is configured to calculate a safe tunnel traversal window from a first time required for the transit vehicle to safely travel from one tunnel end to the other, including any time buffers which may act as a safety buffer; and a second time indicative of the time it will take primary traffic to reach the tunnel. The first time is typically predetermined and may be measured during a testing period. The second time is deduced from traffic information data. For example, for a rail tunnel where the primary traffic are locomotives, the second time may be deduced from at least location, speed, direction and length information for any given locomotive.

At step 306, the controller is configured to determine the transit vehicle should traverse the tunnel when the first time is less than the second time. If the tunnel is not available, one or more secondary task may be implemented at step 307, such as charging of the UAV power source, management of any number of docked UAVs in the vicinity and other tasks typically associated with UAV nests.

In one example, the transit vehicle takes 30 minutes to traverse a tunnel. A train will be passing a tunnel entrance at 1205 and the end of the train will be clearing the tunnel exit by 1225. Transits from the entrance can commence at 1208, following the train through the tunnel. No transits can commence between 1 130 and 1230 from the tunnel exit until the train have cleared.

Further considerations may be made to account for any transit vehicles traversing the tunnel in a situation where multiple transit vehicles are in use.

At step 308, the controller is configured to initiate the tunnel traversal by the transit vehicle when the determination from step 306 confirms that the tunnel is available for use. At step 309, the controller is configured to re-launch the UAV once at least the tunnel traversal is complete, the UAV may then continue on a predetermined navigation path to a final destination. At step 310, the controller is configured to manage the position of the transit vehicle.

Management considerations include whether to send the transit vehicle to the far end of the tunnel or keep it at the present tunnel end.

Operation of the UAV, as transported by the transit vehicle, is dependent on the direction the transit vehicle is to travel through the tunnel relative to any proximate primary vehicle traffic that may also use the tunnel in a similar time period. The controller is therefore configured to determine the direction of tunnel travel of any nearby primary vehicles and compare that to the desired direction defined by the navigation path. Figure 7 shows an example of timing events where the UAV navigation path and primary vehicle are travelling in opposing directions, and Figure 8 shows an example of timing events where the UAV and primary vehicle are travelling in the same direction.

Figure 7 illustrates an exemplary temporal visualisation of temporal event considerations made by the controller module which has determined a train scheduled to enter a tunnel from a direction opposing the direction of intended travel of a transit vehicle. Further, the transit vehicle in this example is assumed to be slower than the speed of the train. The determination made by the controller may be derived from information received from a rail network or from one or more sensors configured to detect train direction, or allow deduction of train direction, and operably connected to the controller.

As described above, the controller is configured to determine a tunnel for use as part of a UAV navigation path and direct the UAV to navigate to the tunnel. The controller will typically define a navigation path as a series of waypoints that the UAV is to travel though as part of its flight plan. The waypoints in some embodiments include additional data such as the time the UAV is to arrive or depart the waypoint, the speed the UAV is to travel between waypoints, the altitude of the waypoint, and UAV flight behaviour at the waypoint - such as to hold position, land, take off, or receive further instructions. The UAV flight controller is configures to receive the waypoint information and control movement of the UAV according to the waypoint specifications.

In some embodiments, the waypoints include instructions for the UAV to land at the tunnel entrance, such as on a landing pad, or directly to the ground transit vehicle which may include a landing pad. The transit vehicle is adapted with one or more sensors adapted to determine when the UAV has landed upon it and then send that data to the controller. When the controller has determined a UAV is attached to a transit vehicle for transportation through the tunnel, the controller will reference the time required by the transit vehicle to travel through the tunnel.

The controller is configured to determine the direction of any vehicle approaching a tunnel comprising a thoroughfare shared by a transit vehicle and determine the direction of travel of the transit vehicle desired to travel through the tunnel. When the direction of travel of the vehicle approaching the tunnel is opposite that of the transit vehicle, the controller is configured to determine a time until the approaching vehicle reaches a tunnel end where the vehicle will enter the tunnel and the transit vehicle will exit the tunnel and the time required by the transit vehicle to travel through the tunnel.

The controller will determine the tunnel is available for use by calculating the time required by the transit vehicle to travel through the tunnel is greater than the time until the

approaching vehicle reaches a tunnel end where the vehicle will enter the tunnel.

There is a shorter amount of time for the transit vehicle to travel through a tunnel when a train is due to travel through a tunnel in the opposing direction as exemplified by Figure 7.

For example, temporal periods 700 and 702 are indicative of time when the train is not in the tunnel, and temporal period 701 indicates the time the train is in the tunnel.

Comparatively, temporal period 704 is indicative of the time required for the transit vehicle to travel through the tunnel, including any time required to enter and exit the tracks. Further, in some embodiments, the controller is configured to add a temporal margin of safety at the beginning 705 and end 706 of the period 704 to produce a total time period 703.

Based on the train direction relative to the desired transit vehicle direction, the tunnel will be available for use during the time periods 708 temporally located either side of the time period 703.

Figure 8 illustrates an exemplary temporal visualisation of temporal event considerations made by the controller module which has determined a train scheduled to enter a tunnel from the same direction as the direction of intended travel of a transit vehicle. In this example, a train and transit vehicle may share the tunnel as long as the transit vehicle has made at least part of its journey when the train enters the tunnel. To coordinate the transit vehicle when the direction of travel of the vehicle approaching the tunnel is the same as that of the transit vehicle, the controller is configured to determine a time until the approaching vehicle reaches a tunnel end where the vehicle will exit the tunnel and the transit vehicle will exit the tunnel, and, determine the tunnel is available for use when the time required by the transit vehicle to travel through the tunnel is greater than the time until the approaching vehicle reaches a tunnel end where the vehicle will exit the tunnel. In each case, the controller is configured to output a signal operable to control action of the transit vehicle when the tunnel is determined as available for use. Re-launch of the UAV may occur when at least the transit vehicle has travelled through the tunnel.

Other tasks operated by the controller include determination of the distance to the closest UAV navigating to an end of a tunnel, and when the transit vehicle is not closest that tunnel end, the controller is configured to signal the transit vehicle to move to the other tunnel end. Conversely, the controller is configured to signal the transit vehicle to stay at the current tunnel end when an inbound UAV is navigating to that same tunnel end. Where in the foregoing description reference has been made to elements or integers having known equivalents, then such equivalents are included as if they were individually set forth. Although the invention has been described by way of example and with reference to particular embodiments, it is to be understood that modifications and/or improvements may be made without departing from the scope or spirit of the invention.