TECHNICAL FIELD

[0001] The present invention relates to monitoring subsidence, wall or slope movement, and the like. In particular, although not exclusively, the present invention relates to monitoring movement of slopes in open cut mines.

BACKGROUND ART

[0002] In open cut mining, large areas of earth are cut away forming pits that are open from above. A slope generally extends down into the pit, the slope separated by berms (or catch benches), which aim to catch rockfall, rather than have it fall all the way to the bottom of the pit.

[0003] While berms may catch small rockfall, one significant danger in open cut mining is that larger parts of slopes may collapse, causing rockfall into the pit. This is clearly undesirable and poses a significant risk to property and human life.

[0004] Prior to such collapse, there is often movement in the wall. As such, various systems exist that monitor movement of slopes, to enable warnings and alerts to be issued.

[0005] In one example, radar and computer vision is used to monitor movement in slopes. Several problems exist with radar and computer vision, however, including a) that it can be difficult to detect small movements, particular over large areas, b) it is difficult to monitor many surfaces due to occlusion, and c) it can be difficult to detect movement in certain directions.

[0006] As such, laser scanners and prisms are often used to monitor movement in slopes. In short, prisms are mounted to a frame or stake, which is attached to or supported by the surface being monitored.

[0007] While highly accurate, a problem with the use of laser scanners and prisms is that prisms must be physically placed along the surface to be monitored. This is a manual task, which is time consuming, costly and dangerous. Furthermore, slopes that are inaccessible, e.g. due to landslide, cannot be monitored at all in this manner.

[0008] Even if prisms are installed when access is still possible, landslides, weather, and even damage from ongoing mining operations, can cause prisms to be lost or become inoperable. The lack of prisms on a slope creates ‘blindspots’ when measuring and monitoring the movement of the slope, and therefore increases danger associated with slope collapse.

[0009] As such, there is clearly a need for an improved slope monitoring system and device. [0010] It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.

SUMMARY OF INVENTION

[0011] The present invention relates to systems and devices for use in monitoring slopes and walls for movement, which may at least partially overcome at least one of the abovementioned disadvantages or provide the consumer with a useful or commercial choice.

[0012] With the foregoing in view, the present invention in one form, resides broadly in a slope monitoring system including: a plurality of prism assemblies, each prism assembly including a reflective prism, and a support frame, for supporting the prism in an elevated position; and an unmanned aircraft configurable to transport each of the prism assemblies from a base to a different position on the slope, such that movement of the slope may be monitored using the prisms and a laser scanner.

[0013] Advantageously, using the unmanned aircraft to deliver prisms onto slopes (e.g. mine walls) alleviates the need for personnel to physically access the slope, significantly reducing risk associated with rockfall. Furthermore, the use of the unmanned aircraft enables prisms to be placed in a more flexible manner, including in areas inaccessible by persons.

[0014] Preferably, the slope monitoring system includes a laser scanner, configured to engage with the reflective prisms. The slope monitoring system may include a theodolite or automated total station (ATS), configured to engage with the reflective prisms.

[0015] Preferably, the support frame comprises a plurality of legs, configured to support the prism on an uneven surface.

[0016] Preferably, the support frame comprises a tripod.

[0017] Preferably, the prism is mounted at or near an apex of the tripod.

[0018] Preferably, the support frame includes a threaded member, for engaging with a corresponding threaded member of the prism.

[0019] Preferably, the threaded member is spaced from legs of the support frame.

[0020] Preferably, the support frame includes a support member, for engaging with a retaining mechanism of the drone. The support member may include an aperture for engaging with a releasable hook of the drone.

[0021] Preferably, the drone includes a support frame, extending downwardly from a body of the drone. The support frame may define an opening for receiving the prism assembly.

[0022] The support frame may be configured to support the drone on an uneven surface.

[0023] The support frame may include first and second support members, which extend downwardly and outwardly from the body of the drone, and define a space therebetween for receiving the prism assembly.

[0024] The prism assembly may be housed entirely within a height of the support frame, enabling the drone and prism assembly to take off and land as a single unit.

[0025] The support frame may be arranged to prevent the prism assembly rotating or swinging, by engaging with at least part of the prism assembly.

[0026] The drone may be configured to support the prism assembly above ground when the drone is supported on the ground.

[0027] Preferably, the support frame is defined by a plurality of linear members. The linear members may comprise tubular members. The tubular members may comprise square tubular members, having a substantially uniform cross section along their length.

[0028] The support frame may be at least partially filled with ballast. The ballast may comprise dirt and/or rock.

[0029] The support frame may be formed of steel.

[0030] Preferably, the unmanned aircraft is a drone. The drone may comprise a helicopter drone.

[0031] In another form, the invention resides broadly in a prism assembly including: a prism receiver, for receiving a reflective prism; and a support frame, for supporting the prism receiver, and thereby a prism received therein, in an elevated position; the support frame including a support member, adapted to enable the prism assembly to be supported and transported to a remote location under an unmanned aircraft.

[0032] Any of the features described herein can be combined in any combination with any one or more of the other features described herein within the scope of the invention. [0033] The reference to any prior art in this specification is not, and should not be taken as an acknowledgement or any form of suggestion that the prior art forms part of the common general knowledge.

BRIEF DESCRIPTION OF DRAWINGS

[0034] Various embodiments of the invention will be described with reference to the following drawings, in which:

[0035] Figure 1 illustrates a simplified schematic of a slope monitoring system, according to an embodiment of the present invention.

[0036] Figure 2 illustrates a front view of a drone of the slope monitoring system of Figure 1 , according to an embodiment of the present invention.

[0037] Figure 3 illustrates a side perspective view of a prism assembly, with the prism removed, of the slope monitoring system of Figure 1 , according to an embodiment of the present invention.

[0038] Figure 4 illustrates a top view of the prism assembly of Figure 3.

[0039] Figure 5 illustrates an end view of the prism assembly of Figure 3.

[0040] Figure 6 illustrates a side view of the prism assembly of Figure 3.

[0041] Figure 7 illustrates a front perspective view of a prism assembly, with the prism removed, according to an alternative embodiment of the present invention.

[0042] Figure 8 illustrates a V-shaped member of the prism assembly of Figure 7, according to an embodiment of the present invention.

[0043] Figure 9 illustrates a central leg member of the prism assembly of Figure 7, according to an embodiment of the present invention.

[0044] Figure 10 illustrates a hanging member of the prism assembly of Figure 7, according to an embodiment of the present invention.

[0045] Figure 1 1 illustrates an end cap of the prism assembly of Figure 7, according to an embodiment of the present invention.

[0046] Figure 12 illustrates a spike member of the prism assembly of Figure 7, according to an embodiment of the present invention. [0047] Preferred features, embodiments and variations of the invention may be discerned from the following Detailed Description which provides sufficient information for those skilled in the art to perform the invention. The Detailed Description is not to be regarded as limiting the scope of the preceding Summary of the Invention in any way.

DESCRIPTION OF EMBODIMENTS

[0048] Figure 1 illustrates a simplified schematic of a slope monitoring system 100, according to an embodiment of the present invention. The slope monitoring system 100 is able to be used to monitor movement in a slope 105, such as a slope (wall) of an open cut mine, to enable precursors of a slope collapse in the form of slope movement to be identified. The slope monitoring system 100 is particularly suited for use in dangerous and inaccessible areas, as it is not reliant on persons physically attending areas to be monitored. Furthermore, areas for monitoring may be chosen based upon need rather than accessibility.

[0049] The slope 105 illustrated in Figure 1 is illustrative of an open cut mine, and includes a plurality of berms 105a, to break the continuity of the slope, and serves as a catch bench. A drone 1 10 is used to fly prism assemblies 115 to the berms 105a, to enable monitoring of the slope 105, using a theodolite or automated total station (ATS) 120, as outlined below.

[0050] In particular, the drone 1 10 receives a prism assembly 1 15 as a payload releasably coupled to the drone 110. As described in further detail below, the payload is received between legs and under a body of the drone 1 10, to enable the drone 1 10 and prism assembly 115 to take off and land as a single unit.

[0051 ] The drone 110, under the control of an operator 125, flies the prism assembly 1 15 to a berm 105a, and delivers the prism assembly 1 15 to the berm 105a such that a prism of the prism assembly 115 is facing and in line-of-sight of the theodolite or ATS 120.

[0052] The process is repeated until a desired number of prism assemblies 115 are positioned on the slope 105. The prism assemblies 1 15 are generally positioned at around 30- 50m intervals along each berm 105a, but any suitable spacing or arrangement may be used, according to geotechnical characteristics of the slope 105 or mine standards or requirements.

[0053] Once the prism assemblies 115 are positioned on the slope 105, they are monitored by the theodolite or ATS 120, periodically and continuously, to monitor long term slope movement. In particular, a laser signal is sent by the theodolite or ATS 120 to each prism of the prism assemblies 115, reflected back and analysed to determine a position of each of the prisms.

[0054] Any suitable technique may be used for such analysis and slope monitoring, but generally smaller movements in the slope 105 may be a precursor to a collapse. As such, the detection of movements of one or more prisms may be indicative of movement of the slope 105, and thus may trigger evacuation and further analysis of the slope 105.

[0055] Figure 2 illustrates a front view of the drone 110, according to an embodiment of the present invention, and Figures 3-6 illustrate various views of the prism assembly 1 15, with the prism removed, for the sake of clarity.

[0056] As best illustrated in Figure 3, the prism assembly 1 15 comprises a tripod formed of three leg members 305, joined at right angles to each other. Each leg member 305 is formed of square tubular steel, that is joined at an apex by welding.

[0057] In particular, first and second leg members 305a, 305b, are joined at a right angle at their respective ends, using a mitre join. A third leg member 305c is then coupled to the first and second leg members 305a, 305b, such that an end of the third leg member 305c is adjacent to the mitre of the first and second leg members 305a, 305b, such that the third leg member 305c extends outwardly from the first and second leg member 305a, 305b at right angles.

[0058] Such configuration enables simple manufacture, using square tubular steel, with only simple straight cuts and welding (or other joining).

[0059] A support member 310 comprising a plate having a hanging aperture extends upwardly from an apex of the prism assembly 1 15, and is used to support the prism assembly 1 15 in the air when transported by the drone 110.

[0060] Finally, a prism holder 315 is coupled to an apex of the legs 305 by a spacing member 320. The prism holder 315 comprises an internally threaded member, configured to receive a threaded shaft of a reflective prism, for coupling same to the prism assembly 1 15.

[0061] The spacing member 320 is configured to space the prism from the legs 305, and provide convenient and simply attachment of the prism to the prism assembly. The spacing member 320 is also able to bend, enabling the prism holder 315 (and thereby prism) to be aligned with a station.

[0062] By utilising tubular steel arranged in a tripod shape, the prism assembly 1 15 is able to be strong and rigid, and able to support the prism on an uneven surface, which is typical for a mine slope.

[0063] Now turning back to Figure 2, the drone 1 10 includes a body 205, from which a rotor assembly 210 comprising a plurality of rotors 215 extends. The rotor assembly 210 extends outwardly from the body 205 in multiple directions, such that the rotors 215 are spaced around the body 205 in all directions, to provide stability and manoeuvrability to the drone 1 10.

[0064] A support frame 220 extends downwardly from the body 205, and is configured to support the drone 1 10 on a surface, and in particular an uneven surface.

[0065] The support frame 220 comprises first and second support members 220a, 220b, which extend downwardly and outwardly from the body 205, and define a space for receiving the prism assembly 1 15. As the prism assembly 1 15 is larger than the body 205, the support frame 220 is generally larger than the body, and much larger than a frame on a traditional drone. This enables the prism assembly 1 15 to be housed entirely within a height of the support frame 220, enabling the drone and prism assembly 115 to take off and land as a single unit.

[0066] The first and second support members 220a, 220b are further arranged to prevent the prism assembly rotating or swinging, by engaging with the legs of the prism assembly 1 15.

[0067] A releasable hook mechanism 225 is provided under the body 205, and is configured to engage with the support member 310 of the prism assembly 115. The releasable hook mechanism 225 is remotely controllable, enabling the operator 125 to fly the drone to a desired location, and selectively release the prism assembly 1 15.

[0068] In use, operator 125 couples the prism assembly 115 to the drone 1 10 using the releasable hook mechanism 225. This can be done while the drone 110 is supported by the support frame 220 on a surface, such as the ground or a work bench, as the support frame 220 lifts the body sufficiently to enable the prism assembly 1 15 to be supported under the drone 110 and from above.

[0069] The prism assembly 115 is supported by the drone 1 10 such that the front of the prism assembly 1 15, and thus the prism 230, is facing a front of the drone 1 10. The drone 1 10 includes a camera, not illustrated, also at a front of the drone 1 10.

[0070] The operator 125 then navigates the drone 110, and thus prism assembly 115, to a desired location and lands the drone 110. The operator 125 is able to use the camera to confirm that the drone 110, and thus the prism 230, are facing towards the theodolite or ATS 120, and that no obstacles are present between the prism and the theodolite or ATS 120, and thereafter release the prism assembly 115.

[0071] The operator 125 may then fly the drone 110 back, land the drone 110, and repeat the process with any remaining prism assemblies 1 15. [0072] If an obstacle is identified between the prism 230 and the theodolite or ATS 120, or the area is otherwise unsuitable, the operator 125 may fly the drone to another area.

[0073] The prism assembly 115 is relatively heavy, and the inventors have found that weight of about 8kg is a good balance between transportability by the drone and stability once in place.

[0074] In some embodiments, the prism assembly 115 is filled with material (ballast) to provide additional weight to the prism assembly 1 15. In such case, the hollow legs may include openings, e.g. at their ends or near an apex of the prism assembly 1 15, which may be releasably opened for filling. Such configuration may reduce transport costs as the prism assemblies 115 may be lightweight when not filled, and filled with dirt or rock on site, to a desired weight.

[0075] The prism assemblies 1 15 may be painted, not only to prevent corrosion, but also to help identify prism assemblies 115 when mixed with dirt/rock, to enable removal therefrom prior to processing. In one embodiment, the prism assemblies are painted bright yellow.

[0076] As will be readily appreciated by the skilled addressee, the prism assemblies 115 may end up mixing with dirt, and ultimately end up in material processing equipment. To avoid damage to material processing equipment, the prism assemblies 115 may be formed of relatively thin material (e.g. thin steel or composite material), which is filled with ballast in the form of dirt or rock typically processed by the material processing equipment.

[0077] Figure 7 illustrates a perspective view of a prism assembly 700, similar to the prism assembly 115, according to an embodiment of the present invention. The prism assembly 700 is well suited to being filled with dirt (or other ballast), and/or adapted to be transported in partially assembled state, as outlined below.

[0078] The prism assembly 700 comprises first and second leg members 705a, 705b, which are joined (e.g. by welding) to form a V-shaped member 800, as outlined in Figure 8. The leg members 705a, 705b are open at their bottoms, and the second leg member 705b is also open at its top.

[0079] This is achieved by joining the first and second leg members 705a, 705b at right angles, e.g. by joining an upper end of the first leg member 705a to a side of the second leg member 705b. This in turn enables the first and second leg members to be cut from lengths of square hollow section (SHS) at 90 degrees, which simplifies the manufacturing process (e.g. welding) significantly compared to other joins (e.g. 45 degree joins).

[0080] The prism assembly 700 further includes a third leg member 705c, which is coupled to a joining plate 715 (e.g. by welding), forming a central leg member 900, as illustrated in Figure 9. A spacing member 320 and prism holder 315 extend from a front surface of the joining plate 715, supporting a prism 720.

[0081] The prism assembly 700 includes a hanging member 1000, similar to the hanging member 310, comprising an upper member including a hanging aperture 1005, from which first and second leg members 1010 extend in a V-shaped manner, as outlined in Figure 10.

[0082] A press-fit member 1015, as illustrated in Figure 11 , is provided on an underside of one of the leg members 1010, and engages with , in a press-fit arrangement, an upper open end of the second leg member 705b.

[0083] Finally, spikes members 1200, as illustrated in Figure 12, are provided at ends of the legs 705a-705c, to provide stability to the prism assembly 700 on uneven surfaces. In particular, end caps 1 100 are provided in ends of the legs 705a-705c, the end caps 1 100 each receiving a spike member 1200.

[0084] The legs 705a-705c have open ends (i.e. open SHS or box section) and receive an insert portion 1105 of an end caps 1 100, such that a pyramid-shaped outer portion 11 10 extends outwardly from an end of the legs 705a-705c when installed when installed thereon.

[0085] A threaded spike retailer portion 1 115 is provided adjacent to an apex of the pyramidshaped outer portion 11 10 and is configured to receive a threaded shaft 1205 of a spike member 1200. In particular, the spike member 1200 includes a body 1210, from which the threaded shaft 1205 extends on one and, and from which a pointed tip member 1215 extends from the other end.

[0086] In use the pointed tip members 1215 engage with a ground surface, which is particularly useful for stability in soft and rough surfaces as the pointed tip members 1215 are able to dig into the ground surface, and adapt to uneven surfaces. The skilled addressee will, however, readily appreciate that the use of spike members 1200 is optional, and in cases where they are not required will simply be omitted from the prism assembly 700.

[0087] In use, the V-shaped member 800, the central leg member 900 and the hanging member 1000 may be transported separately to site. Such configuration reduces overall transport size, as each of the components may be packed in a relatively compact manner (unlike an assembled prism assembly).

[0088] Once on site, the central leg member 900 may be coupled to the V-shaped member 800 using screws extending through the joining plate 715 and into the V-shaped member 800. The hanging member 1000 may then be similarly coupled to the V-shaped member 800 using screws.

[0089] Ends of the first, second and third leg members 705a, 705b, 705c are open, and may be filled with dirt or ballast (optional). End caps 1 100 may then be pressed onto or otherwise fitted to the first, second and third leg members 705a, 705b, 705c to trap the soil.

[0090] Spike members 1200 are then screwed into each of the end caps 1100.

[0091] In some embodiments, the system 100 may be further configured to enable retrieval of prism assemblies 115. In such case, the drone 1 10 may be flown to a prism assembly 115, and land above the prism assembly. An on-board camera on the drone 110 may be used to assist in this process and ensure that the drone is positioned appropriately relative to the prism assembly 115. The releasable hook mechanism 225 may then engage with the support member 310, e.g. with the assistance of magnets, to enable retrieval of the prism assembly 115.

[0092] In some embodiments, the support frame 220 of the drone may include guides, to guide the drone down onto the prism assembly 115 in a desired position. Such configuration may simplify the retrieval of prism assemblies 115, as it may assist alignment of the drone and prism assembly. The guides, and/or other guides, may also function to prevent rotation and/or movement of the prism assembly 115 when supported by the drone.

[0093] In some embodiments, the prism assemblies (or substantial parts thereof) may be painted. The paint may simplify identification of the prism assemblies, e.g. through the use of bright or contrasting colours. The paint may similarly reduce (or prevent) reflectivity of the prism assembly (outside of the prism itself), e.g. using matt paint, to avoid corruption of data caused by reflections from the legs or other parts of the prism assembly.

[0094] In some embodiments, the prism assembly 1 15 may be configured to enable an angle of the prism to be adjusted relative to the legs 305. As an illustrative example, the spacing member 320 may be malleable, or otherwise adjustable.

[0095] While the slope 105 is illustrated in the context of an open cut mine and includes a plurality of berms, the skilled addressee will readily appreciate that other types of slopes or walls may be monitored, including natural slopes (e.g. for landslide) and artificial slopes (e.g. in mining or earthworks).

[0096] Advantageously, the systems described above are able to be used to monitor movement in slopes, such as a slope (wall) of an open cut mine, to enable precursors of a slope collapse in the form of slope movement to be identified, thereby enabling evacuation of the area. The slope monitoring systems are not reliant on persons physically attending areas to be monitored, and are thus particularly suited for use in dangerous and inaccessible areas. Furthermore, the areas for monitoring may be chosen based upon need rather than accessibility.

[0097] In the present specification and claims (if any), the word ‘comprising’ and its derivatives including ‘comprises’ and ‘comprise’ include each of the stated integers but does not exclude the inclusion of one or more further integers.

[0098] Reference throughout this specification to ‘one embodiment’ or ‘an embodiment’ means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases ‘in one embodiment’ or ‘in an embodiment’ in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

[0099] In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims (if any) appropriately interpreted by those skilled in the art.