Method and system for determining a geofence

Abstract

The disclosure relates to a method (200) for determining a geofence (303), the method comprising: - detecting (210) a geometry (GM) of a surface (110) of at least a part of a mining or construction site (302) by utilization of at least one airborne sensor (151); - creating (220), based on the detected geometry (GM), a digital representation (DR) of at least the detected part of the mining or construction site (302); - determining (230), based on the created digital representation (DR), a drivable area (304) of the mining or construction site (302) in which a mining or construction machine (100) can move around safely; and - determining (240) the geofence (303) as an outer boundary of the determined drivable area (304). The disclosure also relates to a corresponding system performing the method, a drilling rig comprising the system, a drilling operator station comprising the system, and to a computer program and a computer-readable medium implementing the method.

Description

[0001] METHOD AND SYSTEM FOR DETERMINING A GEOFENCE

[0002] Technical Field

[0003] The disclosure relates to improved autonomous and remotely controlled mining, and more specifically to a method for determining a geofence associated with a mining or construction site. The disclosure also relates to a system for determining a geofence, to a drilling rig comprising the system, and to a drilling operator station comprising the system. Furthermore, the disclosure also relates to a corresponding computer program and computer-readable medium causing a computer to carry out the method.

[0004] Background

[0005] In the field of mining, there is a constant ongoing process of improving efficiency, productivity, and safety. Full or partial automation and / or remote control of various processes occurring in mining or construction are carried out to achieve this. It is thus often desirable that at least part of the machines that are used in mining or construction can be driven more or less autonomously, i.e. without an operator being required to influence more or less of the control / operation. It may also be desired to remotely control the mining or construction machines, e.g. by utilization of so-called tele-remote drilling control. Hereby, the operator may to a large extent stay away from high-risk zones, in which drilling and blasting takes place.

[0006] Autonomous and remotely controlled mining / drilling is often performed by a fleet, i.e. a plurality of mining or construction machines, such as surface drill rigs, arranged to operate autonomously / remotely and concurrently within a shared mining or construction site. Rock / ore excavation often involves drilling of a set of holes comprised in the mining or construction site. The set of holes, also called blast holes, are then filled with explosive material that is detonated after the holes have been drilled. After the explosion, the ore is transported away and processed for mineral extraction.

[0007] In systems utilizing autonomous and remotely controlled drilling / mining, the outer boundary / perimeter of a geographical area to which the mining or construction machines should be confined may be indicated by a so-called geofence. The geofence may be described as a virtual boundary. The size, form and position of this geographical mining area is thus defined by the geofence encompassing the area. The geofence indicates a limitation of the allowed movements of the active mining or construction machines in order to avoid accidents and / or collisions. The mining or construction machines are for safety reasons not allowed to traverse the geofence. The active mining or construction machines may instead be actively controlled to stay within the geofence. A geofence application may also be configured to set off an alarm on a specific mobile device if a worker and / or a mining or construction machine unintentionally traverse the geofence, for example if the worker and / or machine thereby comes too close to a dangerous area.

[0008] A geofence is conventionally determined together with the drill plan, also called drill pattern, before the drilling starts. The drill plan is a theoretical scheme, which comprises parameters such as for example a number of holes that should be drilled, a spacing between the holes, and the positions of the holes. The drill plan is sent to the one or more mining or construction machines dedicated for executing the drilling according to the drill plan on a mining or construction site, such as a drill bench, possibly by autonomous or remotely controlled drilling. The drill bench is the physical area, e.g. a physical rock area, which is to be drilled and / or excavated according to the drill plan. The geofence is conventionally determined manually, either by drawing it up based on maps in the office, or by manually driving around the geographical mining area with a vehicle especially equipped for geofence determination. These conventional ways of determining geofences are time demanding and therefore costly.

[0009] Summary

[0010] An objective of the embodiments of the disclosure is to provide a solution which mitigates or solves the drawbacks of conventional solutions.

[0011] Another objective of the embodiments of the disclosure is to provide a solution which provides an improved determination of a geofence.

[0012] Yet another object of the disclosure is to increase work safety, efficiency and productivity. Yet another object of the disclosure is to provide a novel and advantageous solution for determining a geofence.

[0013] Yet another object of the disclosure is to provide a flexible solution for determining a geofence.

[0014] Yet another object of the disclosure is to provide a robust and reliable solution for determining a geofence.

[0015] Yet another object of the disclosure is to provide an alternative solution for determining a geofence.

[0016] Yet another object of the disclosure is to improve automation of the process of determining a geofence.

[0017] The above and further objectives are solved by the subject matter of the appended independent claims.

[0018] According to a first aspect of the disclosure, the above mentioned and other objectives are achieved with a method for determining a geofence, the method comprising:

[0019] - detecting a geometry of a surface of at least a part of a mining or construction site by utilization of at least one airborne sensor;

[0020] - creating, based on the detected geometry, a digital representation of at least the detected part of the mining or construction site;

[0021] - determining, based on the created digital representation, a drivable area of the mining or construction site in which a mining or construction machine can move around safely; and

[0022] - determining the geofence as an outer boundary of the determined drivable area.

[0023] An advantage of the method for determining a geofence according to the first aspect is that the at least one airborne sensor can at low cost be sent off to detect the geometry of the surface. Hereby, the surface may be scanned / monitored / mapped as often as necessary to keep the drivable area and the geofence up to date in respect of important changes to a mining or construction site, such as a drill bench.

[0024] Another advantage of the method for determining a geofence according to the first aspect is that the at least one airborne sensor provides more flexibility in detecting the geometry of the surface, compared with manually driving around the geographical mining area with a vehicle especially equipped for geofence determination.

[0025] Another advantage of the method for determining a geofence according to the first aspect is that the at least one airborne sensor provides improved safety in detecting the geometry of the surface, compared with manually driving around the geographical mining area with a vehicle especially equipped for geofence determination.

[0026] Initially, the drill plan is sent to the mining or construction machines such that they can execute the drill plan autonomously. Alternatively, the drill plan is sent to an operator station, such that the mining or construction machines can be remotely controlled to execute the drill plan. However, real world changes of the drill plan and / or within the mining or construction site may occur during the drilling operation. Such changes may be dynamically detected according to the presented method for determining a geofence. For example, the drilling order of holes, the positions of the holes and / or the surface of a drill bench at a mining or construction site may change during a drilling operation. These changes are detected by repeated scanned / monitored / mapped of the drill bench performed by utilization of the airborne sensor.

[0027] Thus, the method for determining a geofence according to the first aspect has the advantage of providing a robust and reliable determination of a geofence.

[0028] For example, if a part of the drill bench, and thus a part of the drivable area has been dug away, such that the previous surface of that part of the drill bench does no longer exist, this will be discovered by the surface detection performed by the airborne sensor. Hereby, the drivable area can be updated correspondingly, such that it matches the current state of the drill bench, and such that there still is rock present to execute the drill plan on.

[0029] Also, by scanning / mapping / monitoring the surface from a bird’s eye perspective using the herein presented airborne sensor provides for a high-quality detection of the surface, and therefore also results in a high-quality determination of the geofence. The at least one airborne sensor may be autonomously deployed without need for a pilot, e.g. as mounted on drone, which saves man hours and therefore also costs that were associated with conventional geofence determination, performed by personal driving around the drill bench in special geofence determination equipped vehicles. Therefore, the at least one airborne sensor may be deployed as often as necessary to keep the geofence being determined and updated in near real time, such that it is always relevant for the current drill bench, i.e. such that it matches the surface of the drivable area currently being safe to travel for the mining or construction machines.

[0030] Thanks to the exact high-quality determination of the geofence, always being updated such that it matches the current state of the drill bench, the risk for geofence related accidents is considerably reduced. Also, the burden of creating a geofence is moved from being a manual process to being an automated machine handled process, which reduces the risks for errors.

[0031] In an embodiment of a method according to the first aspect, the method further comprises:

[0032] - providing the determined geofence to one or more mining or construction machines configured to execute mining operations according to a drill plan associated with the mining or construction site.

[0033] An advantage with this embodiment is that the one or more mining or construction machines hereby may be controlled based on an up to date geofence, such that accidents due to changing conditions of the mining or construction site are avoided.

[0034] In an embodiment of a method according to the first aspect, the one or more mining or construction machines comprise one of more in the group of: - an autonomous mining or construction machine; and

[0035] - a remotely controlled mining or construction machine.

[0036] By utilizing the herein described method for determining a geofence in autonomous and / or remotely controlled mining, the risks for geofence related accidents is considerably reduced. Autonomous and / or remotely controlled mining or construction machines lacks the human eye control at site, which in locally controlled mining or construction machines often prevents accidents. Therefore, the herein presented method, providing a high-quality geofence, which may be updated at a frequency such that it covers the relevant changes of the mining or construction site during a mining or construction operation, compensates for the non-existing human eye control in autonomous and / or remotely controlled mining or construction machines.

[0037] In an embodiment of a method according to the first aspect, the determined geofence is an initial geofence determined for an initially determined drivable area.

[0038] An advantage with this embodiment is that the herein presented high quality and efficient determination of the geofence may be utilized for mapping the drill plan to a geographical area that is going to be drilled, i.e. for determining the geofence before drilling according to the drill plan starts. In conventional solutions, such determination of the geofence has taken up large personal resources, and has therefore also generated large costs, since it has traditionally been performed by driving especially equipped vehicles around the borders of the geographical area to be drilled. According to the herein presented geofence determination, an airborne sensor mounted e.g. on a drone may simply be deployed to scan / map / monitor the surface of the mining or construction site, which is a considerably faster and less costly procedure.

[0039] In an embodiment of a method according to the first aspect, the determined geofence is a subsequent geofence determined for a subsequently determined drivable area.

[0040] An advantage with this embodiment is that the herein presented geofence determination may be used for updating a previously determined geofence at a frequency such that it covers the physical changes of the drill bench at a mining or construction site. In other words, the geofence follows and matches the changing appearance of the drill bench as the drilling operation proceeds.

[0041] In an embodiment of a method according to the first aspect, the method further comprises:

[0042] - comparing the subsequent geofence with a previously determined geofence;

[0043] - detecting that there are one or more differences between the subsequent geofence and the previously determined geofence; and

[0044] - indicating the detected one or more differences.

[0045] An advantage with this embodiment is that relevant changes of the geofence are indicated to an operator and / or system controlling at least one mining or construction machine, such that they are alerted / informed that important changes have taken place. Hereby, the risk e.g. for a mining or construction machine falling / tilting over a crest of a free face is reduced.

[0046] In an embodiment of a method according to the first aspect, the detected geometry comprises information associated with one or more in the group of:

[0047] - slopes;

[0048] - inclinations;

[0049] - changes in inclination

[0050] - boulders; and

[0051] - cracks.

[0052] An advantage with this embodiment is that for mining or construction machines important geometry parameters are detected by the airborne sensor. Mining or construction machines need the ground to be relatively flat, with only modest inclinations and changes in inclinations, in order to efficiently and safely be able perform execute the drill plan. By detecting such parameters with the airborne sensor, these important geometry parameters are taken into consideration when the drivable area is determined, resulting in a high-quality determination of the drivable area. In an embodiment of a method according to the first aspect, the at least one airborne sensor is mounted on at least one aerial entity in the group of:

[0053] - a drone;

[0054] - a helicopter; and

[0055] - an aircraft.

[0056] An advantage with this embodiment is that a suitable flying entity may be chosen for the current situation at the mining or construction site. A drone, which does not need a pilot, may in many situations be a low cost and efficient choice. One or more drones may for example be docked on a mining or construction machine and / or on an operator station, such that they can deploy quickly and, within the mining or construction site, i.e. close to the surface to be scanned / monitored / mapped. In some situations, a pilot-controlled helicopter and / or aircraft may be flown over the mining or construction site anyway, and may then be the best choice for mounting the airborne sensor.

[0057] In an embodiment of a method according to the first aspect, the at least one airborne sensor is one or more in the group of:

[0058] - a light detecting and ranging sensor; and

[0059] - a photogrammetry sensor.

[0060] The airborne sensor may thus the chosen based on the current situation at the mining or construction site and / or cost, such that a high-quality detection of the geometry GM is provided at a reasonable cost.

[0061] In an embodiment of a method according to the first aspect, the digital representation comprises a point cloud.

[0062] The point cloud is a set of data points in space which may represent a three dimensional digital twin of the surface having been detected by the airborne sensor, e.g. being a photogrammetry sensor. Based on a digital copy of the surface in form of a point cloud, a high-quality determination of the drivable area may be performed. In an embodiment of a method according to the first aspect, the detection of the geometry is preformed multiple times during mining or construction according to a drill plan associated with the mining or construction site.

[0063] Hereby, it is possible to update the geofence as the mining progresses according to the drill plan, such that there is always an up to date geofence. The risk for accidents due to changes of the drill bench at the mining or construction site is considerably reduced, since the geofence dynamically changes together with the drill bench.

[0064] In an embodiment of a method according to the first aspect, the detection of the geometry is performed with one of the intervals in the group of:

[0065] - one detection per 12 hours;

[0066] - one detection per day; and

[0067] - one detection per 2 days.

[0068] Hereby, a suitable update frequency for the geofence updates may be selected based on the tempo in which the appearance of the drill bench changes at the mining or construction site during the drilling process. Thus, when correctly chosen, the update frequency covers all changes relevant for the drivable area and the mining or construction machines operating in the drivable area.

[0069] In an embodiment of a method according to the first aspect, the mining or construction site comprises a drill bench with a free face at a crest of the drill bench, and the method comprises:

[0070] - detecting at least the crest by utiliation of the at least one airborne sensor;

[0071] - creating, based on the detection of at least the crest, a digital representation of at least a part of the drill bench including the crest;

[0072] - determining a drivable area such that there is an offset distance between the drivable area and the crest;

[0073] - determining the geofence based on the determined drivable area.

[0074] An advantage with this embodiment is that free faces and crests are quickly detected by the scanning / monitoring / mapping performed by the airborne sensor, which may be repeatably deployed e.g. on a drone. Also, the drivable area is determined with a safety margin to the crest, such that it is safe for the mining or construction machines to travel within the entire determined drivable area. New free faces are very important to be aware of for autonomous and / or remotely controlled mining or construction machines, to avoid movements across the crest, which would cause tilting of a mining or construction machine.

[0075] In an embodiment of a method according to the first aspect, the offset distance is in the interval of 0.5 to 3 meters, or in the interval of 1 to 2 meters.

[0076] An advantage with this embodiment is that the offset distance may be chosen as a safety margin, based e.g. on the type of rock at the crest, such that the entire determined drivable area may be safely travelled by the mining or construction machines.

[0077] In an embodiment of a method according to the first aspect, the step of detecting the geometry is preceeded by the step of:

[0078] - preparing one or more properties of the mining or construction site such that one or more parameters associated with the mining or construction site are fulfilled.

[0079] There are a number of rules / restrictions / demands on a number of properties of the mining or construction site, which should be fulfilled in order for the mining or construction site to be drivable by the mining or construction machines, in terms of allowable inclinations, slopes, angles and other features. It is therefore often necessary to prepare the mining or construction site before drilling can start, which results in a larger possible drivable area and more efficient drilling.

[0080] According to a second aspect of the disclosure, the above mentioned and other objectives are achieved with a system for determining a geofence, the system being configured to perform the herein described method.

[0081] The system according to the second aspect can be extended into embodiments corresponding to the embodiments of the method according to the first aspect. Hence, an embodiment of the system comprises the feature(s) of the corresponding embodiment of the method. The advantages of the system according to the second aspect and its embodiments are the same as those for the corresponding aspect and embodiments of the method according to the first aspect mentioned above.

[0082] According to a third aspect of the disclosure, the above mentioned and other objectives are achieved with a drilling rig comprising the herein described system for determining a geofence.

[0083] The advantages of the drilling rig according to the third aspect and its embodiments are the same as those for the corresponding aspect and embodiments of the method according to the first aspect mentioned above.

[0084] According to a fourth aspect of the disclosure, the above mentioned and other objectives are achieved with a drilling operator station comprising the herein described system for determining a geofence.

[0085] The advantages of the drilling operator station according to the fourth aspect and its embodiments are the same as those for the corresponding aspect and embodiments of the method according to the first aspect mentioned above.

[0086] Embodiments of the disclosure also relate to a computer program, characterized in program code, which when run by at least one processor causes the at least one processor to execute any method according to embodiments of the disclosure. Further, embodiments of the disclosure also relate to a computer program product comprising a computer readable medium and the mentioned computer program, wherein the computer program is included in the computer readable medium, and may comprises one or more from the group of: read-only memory (ROM), programmable ROM (PROM), erasable PROM (EPROM), flash memory, electrically erasable PROM (EEPROM), hard disk drive, etc.

[0087] The computer program has the advantage of improving automation of the method / process of determining a geofence. Further applications and advantages of embodiments of the disclosure will be apparent from the following detailed description.

[0088] Brief Description of the Drawings

[0089] The appended drawings are intended to clarify and explain different embodiments of the disclosure, in which:

[0090] - Fig. 1 shows a flow chart for an exemplary method according to embodiments of the disclosure;

[0091] - Figs. 2a-b schematically illustrate a non-limiting exemplary drill bench and geofence;

[0092] - Fig. 3 schematically illustrates an exemplary mining or construction machine and operator station, in which embodiments of the disclosure may be utilized;

[0093] - Fig. 4 shows a flow chart for exemplary methods according to embodiments of the disclosure; and

[0094] - Fig. 5 schematically illustrates a control unit according to some embodiments of the disclosure.

[0095] Detailed Description

[0096] As mentioned above, the drill plan is a theoretical / wanted scheme conventionally determined by e.g. a mining / drilling engineer before the drilling takes place. The geofence is conventionally determined before the drilling takes place according to the drill plan by having personnel drawing up the geofence based on maps or by having personnel driving around the geographical mining or construction site, such as a drill bench, and marking geofence coordinates. Conventional geofence determination it thus time demanding and / or costly.

[0097] Also, due to dynamically changing circumstances and / or due to circumstances unforeseen when the drill plan was determined before the actual drilling takes place, there may be a mismatch between the surface of the area for which the theoretical drill plan was determined and the real-world surface of the drill bench at the mining or construction site during the drilling / mining operation. Thus, the surface of the real- world drill bench may, after some time of drilling / mining, no longer correspond to the surface existing or anticipated when the drill plan was determined. Therefore, the previously determined geofence may no longer apply to the current drill bench. This mismatch may cause dangerous situations and / or accidents.

[0098] Thus, the drill plan is a theoretical / wanted scheme conventionally determined before the drilling takes place. The drill plan is sent to the one or more milling machines dedicated for executing the drilling according to the drill plan on a drill bench, possibly by autonomous or remotely controlled drilling. However, the surface of the real-world drill bench may, after some time of drilling / mining, no longer correspond to the surface for which the drill plan and the geofence was conventionally determined, such that the previously determined geofence is no longer valid and secure for the current drill bench appearance.

[0099] Figure 1 illustrates a flow chart for a method 200 for determining a geofence. Figure 2 schematically shows some features of a drilling area being mentioned in the steps of the method. Figure 2 is explained more in detail below.

[0100] In a first step 210, a geometry GM of a surface 110 of at least a part of a mining or construction site 302, such as a drill bench, is detected by utilization of at least one airborne sensor 151. As mentioned above, the mining or construction site 302 is a physical area which is drilled and / or excavated according to a drill plan 301 . The mining or construction site 302 may for example be rectangular, and may as a nonlimiting example have a size in an interval of 50x200 meters to 200x1000 meters. The geometry GM may comprise a number of forms associated with the detected surface 110, as described below.

[0101] In a second step 220, a digital representation DR of at least the detected part of the mining or construction site 302 is created based on the detected geometry GM. The digital representation DR may be of various types and may comprise various information, as described below.

[0102] In a third step 230, a drivable area 304 of the mining or construction site 302, in which a mining or construction machine 100 can move around safely, is determined based on the created digital representation DR. There are various ways to determine the drivable area 304, as described below. Basically, the ground has to fulfill a number of regulations to be classified as a drivable area. Since mining or construction machines need to operate on an essentially flat ground, there are requirements regarding slopes / inclinations that need to be fulfilled, for example maximally allowed inclination angles which may be compensated by lift jacks of the mining or construction machines. As another example, there should be no larger boulders or cracks / voids within the drivable area. Basically, the drivable area may be determined as the area within which the mining or construction machines may safely move around and also can perform its mining or construction tasks, such as drilling tasks.

[0103] In a fourth step 240, the geofence 303 is determined as an outer boundary of the determined drivable area 304. Hereby, the geofence defines the border of the determined drivable area 304, which secures that it will be safe for mining or construction machines to travel inside of the geofence 303, i.e. within the determined drivable area 304.

[0104] Figures 2a-b schematically illustrates a non-limiting example of a drilling area, which will be used for explaining the herein presented disclosures. The mining or construction site 302, here exemplified as a drill bench, is the physical area associated to the drill plan 301 . Thus, the drill plan 301 is executed on the physical drill bench 302. According to the herein presented disclosures, a drivable area 304 is determined 230 as an area where it is safe for the mining or construction machines 100 to travel around at the drill bench 302. The drivable area 304 is confined within the determined geofence 303, being e.g. a polygon, which means that the mining or construction machines 100 are restricted from traversing the geofence 303, i.e. the mining or construction machines 100 are not allowed to leave the drivable area 304 when working.

[0105] The drill plan 301 may comprise, among other parameters, the number of holes 310 to be drilled, the spacing 311 between these holes, possibly in multiple directions, and the positions of each one of the holes 310. The mining or construction machines 100 are then sent to the physical drill bench 302 to autonomously and / or remotely controlled execute the previously determined drill plan 301 . In figures 2a-b, two mining or construction machines 100, such as drilling machines, are illustrated in the drivable area 304. However, essentially any number of mining or construction machines 100 may be put to work to execute the drill plan 301 , as a coordinated fleet of mining or construction machines 100.

[0106] By determining the geofence 303 according to the presented method 200, the mining or construction machines 100 will always be safe to travel inside of the geofence 303, i.e. within the determined drivable area 304, since the geofence 303 will be updated based on the current state of the drill bench 302. Thus, if the geometry GM of the drill bench 302 has changed since a previous 303Prev or initial 303init geofence was determined, the subsequently determined geofence 303subseq will also be updated correspondingly.

[0107] Figure 3 schematically illustrates a system 130 for determining a geofence 303 according to the herein presented disclosures. Thus the system 130 is configured to perform the herein described method steps.

[0108] The system 130 may be described as comprising a detection entity 131 , configured to detect 210 a geometry GM of a surface 100 of at least a part of a mining or construction site 302, such as a drill bench, by utilization of at least one airborne sensor 151 . The system 130 may furhter comprise a creation entity 132 configured to create 220 a digital representation DR of at least the detected part of the mining or construction site 302 based on the detected geometry GM. The system 130 may further comprise a determination entity 133 configured to determine 230 a drivable area 304 of the mining or construction site 302, in which a mining or construction machine 100 can move around safely, based on the created digital representation DR. The system 130 may further comprise a determination entity 134 configured to determine 240 the geofence 303 as an outer boundary of the determined drivable area 304, e.g. as a polygon around the drivable area 304.

[0109] Thus, the system 130 for determining the geofence 303 utilizes at least one airborne sensor 151 , which may be mounted on at least one suitable aerial entity 150, such as a drone, a helicopter and / or an aircraft. The sensor 151 may be airborne in essentially any way such that it is possible for the sensor 151 to monitor / scan / survey the mining or construction site 302. Thus, the sensor 151 may also be mounted on a ballong, a wire or any other suitable arrangement making it possible for the sensor 151 to monitor / scan / survey the surface 110 of the mining or construction site 302 from above. The aerial entity, being e.g. a drone, may be docked at the mining or construction machine 100 or the oprator station 160, such that it is located locally at the drilling site for quick and short range deployment.

[0110] The at least one airborne sensor 151 may be any suitable sensor configured to detect forms and / or shapes, i.e. the geometry GM, of some kind of surface / area. One such sensor 151 is a light detecting and ranging (LIDAR) sensor, also known as a laser imaging detection and ranging sensor. The LIDAR sensor determines ranges by targeting a surface with laser and measuring the time for the reflected light to return to the sensor. The LIDAR sensor may operate in a fixed direction, e.g. in the vertical direction, and / or it may scan multiple directions, which it is known as LIDAR scanning or 3D laser scanning.

[0111] Another example of such a sensor 151 is a photogrammetry sensor. Photogrammetry obtains reliable information about physical objects and surfaces by recording, measuring and interpreting photographic images and patterns of electromagnetic radiant imagery and / or other phenomena. For example, extraction of three- dimensional measurements from two-dimensional data, i.e. images, may be provided by photogrammetry.

[0112] Thus, by the monitoring / scanning / mapping utilizing the at least one airborne sensor 151 , the geometry GM of the surface 110 of at least part of the mining or construction site 302 may be detected 210. Hereby, any shape, form, or formation of the surface 110 may be detected 210 as, and comprised in, the geometry GM, including for example, slopes, inclinations, changes in inclination, boulders, and / or cracks of the surface 110.

[0113] As mentioned above, based on the detected geometry GM, a digital representation DR may be created 220 for at least a part of the mining or construction site 302. The digital representation DR may be essentially any suitable virtual and / or digital twin / copy / model of the surface 110 of at least part of the mining or construction site 302. For example the digital representation DR may comprise a point cloud, being a discrete set of data points in space representing a three dimensional twin / copy / model of the surface 110. Each point position may then be defined by its set of Cartesian coordinates (X, Y, Z). The point cloud may for example be produced by utilization of the photogrammetry sensor, by measuring and analyzing multiple points on the surface 110.

[0114] The system 130 for determining a geofence 303 may, according to an aspect, be comprised onboard a mining or construction machine, such as drilling rig 100. Thus, the onboard system 130 for determining a geofence 303 is then configured to communicate with the airborne sensor 151 according to any suitable communication method / scheme / protocol, via suitable communication equipment 140, to control the sensor 151 to detect 210 the geometry GM and to provide / transmit / send the detected geometry GM to the system 130. The system is further configured to receive the detected geometry GM from the sensor 151 , to create 220 the digital representation DR, to determine 230 the drivable area 304, and to determine 240 the geofence 303, as explained herein. Since the geofence 303 is determined 240 by the onboard system 130, the geofence 303 may be directly utilized in the drilling rig 100 when controlling the movements of the drilling rig 100 within the drivable area 304.

[0115] Such a drilling rig 100 is schematicaly illustrated in figure 3. The drilling rig 100 may be utilized for drilling holes 310 of a mining or construction site 302, such as a drill bench as shown in figures 2a-b. The illustrated drilling rig 100 is only exemplary mining or construction machine, and the herein presented disclosures may be implemented using various kinds of mining or construction machines and / or drill rigs of various designs. The drilling rig 100 illustrated in figure 3 is a surface drilling rig 100 being used to drill vertical or substantially vertical holes 310 using a drill tool attached to a drilling machine via a drill string. The drilling machine may be slidably arranged along a feed beam. These elements are conventional and not explicitly illustrated. These conventional elements are in figure 3 instead commonly represented by a drill tower 102 and a schematically indicated drill string 103 illustrating an indicating ongoing drilling. The general technology used when drilling using a drilling rig 100 as shown in figure 3 is well known as such. The drill tower 102 and the drill string 103 are carried by a carrier 101 , comprising crawlers and / or wheels 104 facilitating the drilling rig 100 to move from one position to another, for example between holes 310 of the drill bench 302 to be drilled.

[0116] The system 130 for determining a geofence 303 may, according to an aspect, be configured offboard in a drilling operator station 160. The drilling operator station 160 may be positioned relatively closely to the mining or construction site 302 and the mining or construction machines 100, e.g. in a local on-site operator facility, or may be positioned far away from the the mining or construction site 302 and the mining or construction machines 100, e.g. in a distant off-site office. The offboard system 130 for determining a geofence 303 is then configured communicate with the airborne sensor 151 according to any suitable communication method / scheme / protocol and equipment 140 to control the sensor 151 to detect 210 the geometry GM and to transmit / send the detected geometry GM to the system 130. The system 130 is further configured to receive the detected geometry GM from the sensor 151 , to create 220 the digital representation DR, to determine 230 the drivable area 304, and to determine 240 the geofence 303. Since the geofence 303 is determined 240 by the offboard system 130, the system 130 is further configured to communicate the geofence 303 to the drilling rig 100 according to any suitable communication method / scheme / protocol and equipment 140. Hereby, the drilling rig 100 is controlled to move only within the drivable area 304.

[0117] Figure 4 shows a flowchart for the method 200 according to various embodiments. The first step 210 of detecting the geometry GM of the surface 110, the second step 220 of creating the digital representation DR, the third step 230 of determining the drivable area 304, and the fourth step 240 of determining the geofence 303 are described above.

[0118] According to an embodiment, the one or more properties of the mining or construction site 302 are prepared in a preparation step 205 proceeding the first step 210 of detection of the geometry GM. By the preparation 205, one or more parameters requirements associated with the mining or construction site 302 are fulfilled. There are generally requirements / limitations on a number of parameters that decide if an area is drivable or not. The preparation 205 facilitates that one or more of these parameters fulfil their respective requirements / limits. For example, incli nations / g rades may be reduced, soft ground may be cleared and / or gaps / voids may be fille. One or more bulldozers may here be used for flattening / evening out the ground before the detection 210 of the geometry GM is performed, such that too steep inclinations and / or boulders are removed from the mining or construction site 302. A larger drivable area 304, and therfore also a wider / longer geofence 303, may be provided by proper preparation of the ground, which enhances the productivity of the mining process.

[0119] According to an embodiment, the method 200 further comprises a fifth step 250 of providing the determined geofence 303 to one or more mining or construction machines 100, where these one or more mining or construction machines 100 are configured to execute mining operations according to a drill plan 301 associated with the mining or construction site 302. As mentioned above, the mining or construction machines may be essentially any machine 100 moving around autonomously and / or remotely controlled within the drivable area 304, such as for example a drilling machine 100, a truck, or an inspection vehicle. These mining or construction machines 100 are controlled to stay within the drivable area 304, i.e. to not move outside the determined geofence 303.

[0120] The geofence 303 being determined in the fourth step 240 may, according to an embodiment, be an initial geofence 303init, i.e. a first geofence being determined at the start of a drilling operation for an initially determined drivable area 304init. Thus, the initial geofence 303init encompasses the determined drivable area 304init at the start of the driling operation, or is at least the first geofence having been determined for the mining or construction site 302.

[0121] According to an embodiment, the detection 210 of the geometry GM is preformed multiple times during the drilling takes place, i.e. during a mining operation according to the drill plan 301 . Thus, the creation 220 of the digital representation 230, and the determination 240 of the geofence 303 may thus be performed also during the mining operation. Hereby, an updated driavable area 304 and a correspondingly updated geofence 303 may be provided also after some time of mining. For example, the detection 210 of the geometry GM may be performed every 12 hours, every day, every second day, or with another suitable interval. Generally, the updating frequency of the detection 210 of the geometry GM, and the resulting determination 240 of the geofence 303, may be selected based on the tempo / speed of the current mining operation. Thus, if the mining operation proceeds relatively quickly, then a higher update frequency, i.e. a shorter interval, may be selected. Conversely, if the mining operation is relative slow, a lower update frequency, i.e. a longer interval, may be selected. By selecting a detection frequency based on the speed of the mining operation, a detection frequency adaption to the specific mining operation is provided, which may be seen as a, for the mining operation, near real time detection 210 of the geometry GM. Thus, a for the current mining operation near real time geofence 303 determination 240 may be provided if a suitable detection update frequency is chosen.

[0122] According to an embodiment, the geofence 303 being determined in the fourth step 240 may thus, if more than one detection 210 of the geometry GM is preformed, be a subsequently determined geofence 303subseq determined for a subsequently determined drivable area 304Subseq. Thus, the subsequent geofence 303subseq then encompasses the subsequently determined drivable area 304Subseq, e.g. after a time period comprising drilling activities has passed.

[0123] When the geofence 303 is a subsequently determined geofence 303subseq, the method 200 further may comprise a sixth step 260 of comparing the subsequent geofence 303subseq with a previously determined geofence 303Prev. The previously determined geofence 303Prev may here be an initial geofence 303init or a foregoing / preceeding subsequent geofence 303subseq.

[0124] The method then further comprises a seventh step 270 of detecting that there are one or more differences between the subsequent geofence 303subseq and the previously determined geofence 303Prev. The detection 270 of these differences may here comprise a comparison of the subsequent geofence 303subseq and the previous geofence 303Prev, and identifying one or more differences between them. The method 200 then further comprises an eight step 280 of indicating 280 the detected one or more differences. Thus, the detected one or more differences may here be indicated for example to an operator and / or a system controlling the geofence 303. Hereby, the operator and / or system controlling the geofence 303 are then alerted when an important change og the geofence has occurred.

[0125] According to an embodiment, which will be explained in connection with figures 2a-b and 4, the geofence 303 is determined for a drill bench 302 comprising a free face 305 at a crest 306 of the drill bench 302. According to the embodiment, the above described first step 210 comprises the step of detecting 21 1 at least the crest 306 by utiliation of the at least one airborne sensor 151 , i.e. at least the crest 306 is included in the detected geometry GM. The above described second step 220 comprises the step of creating 221 a digital representation DR of at least a part of the drill bench 302 including the crest 306, where this creation 221 is based on the detection 211 of at least the crest 306. The above described third step 230 comprises the step of determining 231 a drivable area 304 such that there is an offset distance 307 between the drivable area 304 and the crest 306. The offset distance 307 may, according to various embodiments be in the interval of 0.5 to 3 meters, or in the interval of 1 to 2 meters, depending on for example various properties / features of the rock at the crest 306 and / or and close to the crest 306. Further, the fourth step 240 comprises the step of determining 241 the geofence 303 based on the determined drivable area 304.

[0126] Figures 2a-b schematically illustrate a non-limiting example of such determination of the geofence 303 for a drill bench 302 comprising a free face 305. Figure 2a schematically illustrates an initial or previous drivable area 304init / 304Prev of a drill bench 302, where the initial or previous drivable area 304init / 304Prev indicate an area where it initially or previously, i.e. at the beginning of the drilling operation or at an earlier time instance under the drilling operation, has been determined safe for the mining or construction machines 100 to travel around.

[0127] After some time of mining operation, a free face 305 has been created by the mining operation, as illustrated in figure 2b. The free face 305 starts at a crest 306 of the drill bench 302. In conventional solutions, in which the geofence 303 is initially determined and thereafter not updated, or is updated with very long intervals, the mining or construction machines 100, may not be aware of that a large part of the drill bench 302 is gone, i.e. may not know that the free face 305 and the crest 306 exist. There is therefore a risk that the mining or construction machines 100 drive over the crest 305 and fall down the free face 305, since they believe that the initial or previous drivable area 304init / 304Prev is still intact.

[0128] However, according to the here in presented aspects and embodiments, the update frequency of the determination 240 of the geofence 303 may be selected such that, for the slowly changing mining conditions, a near real time determination 240 of the geofence 303 is provided. This is made possible by the simple and low cost detection 210 of the geometry GM by utilizing the at least one airborne sensor 151 , e.g. carried by a drone 150, which can be performed as often as needed to keep the geofence 303 properly updated.

[0129] Thus, according to various embodiments, a subsequent geofence 303subseq is determined at a subsequent time instance for a subsequently determined drivable area 304Subseq, such as the one illustrated in figure 2b. Since the airborne sensor 151 scans / maps / monitors the surface 1 10 of the drill bench 302 from above, it will easily spot the free face 305 and its crest 306 schematically illustrated in figure 2b. Thus, the determination 230 drivable area results in the subsequently determined drivable area 304Subseq, taking the free face 305 and the crest 306 into consideration. Thus, as illustrated in figure 2b, the determined subsequent drivable area 304Subseq is considerably smaller than the initial or previous drivable area 304init / 304Prev illustrated in figure 2a. Also, the determined subsequent geofence 303subseq efficiently protects the mining or construction machines 100 from running over the creast 306 and off the free face 305, since there is an safety offset distance 307 between the the determined subsequent geofence 303subseq and the crest 306.

[0130] As mentioned above, the subsequent geofence 303subseq illustrated in figure 2b may be compared 260 with the previously determined geofence 303Prev illustrated in figure 2a, and the differences may be detected 270 and indicated 280 to an operator and / or system controlling the mining or construction machines 100, such that the operator and / or system are alerted that there has been critical changes to the drivable area during the mining operation.

[0131] Thus, by repeated determination of the geofence 303 multiple times during the mining operation, by deploying an airborne sensor 151 mounted e.g. at a drone to detect 210 the geometry GM, the risk for accidents related to controlling mining or construction machines 100 based on outdated geofence data is considerably reduced. There will essentially always be an up-to-date geofence 303, which it will be safe to travel within.

[0132] Figure 5 schematically illustrates a control unit 130. The drilling rig 100 and / or the operator station 160 shown in figure 3 comprise a control system comprising at least one control unit 130, which controls various functions of the drilling rig 100, e.g., by suitable control of various actuators / motors / pumps etc. Drilling rigs of the disclosed kind may comprise more than one control unit, where each control unit, respectively, may be arranged to be responsible for different functions of the drilling rig 100. According to examples of the disclosure, the first 210, second 220, third 230 and fourth 240 method steps, and any other herein described step, may be controlled by any suitable control unit of the drilling rig 100 and / or the operator station 160, such as the control unit 130. Correspondingly, the herein disclosed detection entity 131 , creation entity 132, determination entity 133, and determination entity 134 may be implemented in any suitable control unit of the drilling rig 100 and / or of the operator station 160, such as the control unit 130, possibly as one or more sections of programming code. The functionality of the disclosure may also be divided among more than one control units. According to examples of the disclosure, one control unit may comprise at least part of the functionality of one or more of the detection entity 131 , the creation entity 132, the determination entity 133, and the determination entity 134, whereas another control unit may comprise at least part of the functionality of one or more of the detection entity 131 , the creation entity 132, the determination entity 133, and the determination entity 134, and so on.

[0133] The control unit 130 comprises a data processing unit 141 which, based on received signals, and by means of suitable calculations, performs the steps according to the examples of the disclosure described herein. The processing unit 141 can, for example, be constituted by a processor, such as a digital signal processor. The control unit 140 may be controlled by means of a computer program 142 that is, e.g., built into the processor or being connected thereto. The computer program may be generated by means of an appropriate programming language and be stored in a non-transitory computer memory 143 that is integrated in the processor or form a separate part of the control unit 130. The control unit 130 may further comprises a transceiver module 144 for receiving / transmitting signals. The transceiver module 144 may, e.g., also constitute an interface for other signals being received and / or transmitted by the control unit 130.

[0134] The processing unit 141 may be referred to and / or may comprise one or more general-purpose central processing units (CPUs), one or more digital signal processors (DSPs), one or more application-specific integrated circuits (ASICs), one or more field programmable gate arrays (FPGAs), one or more programmable logic devices, or any other one or more discrete or logic devices / components / circuits / chipsets. The computer memory 143 may be a readonly memory (ROM), a random access memory (RAM), or a non-volatile RAM (NVRAM). The transceiver module 144 may be a transceiver circuit, a power controller, or an interface providing capability to communicate with other communication modules or communication devices. The transceiver module 144, computer memory 143 and / or processing unit 141 may be implemented in separate components or may be implemented in a common component.

[0135] Finally, it should be understood that the disclosure is not limited to the embodiments described above, but also relates to and incorporates all embodiments within the scope of the appended independent claims.

Claims

CLAIMS1 . A method (200) for determining a geofence (303), the method comprising:- detecting (210) a geometry (GM) of a surface (1 10) of at least a part of a mining or construction site (302) by utilization of at least one airborne sensor (151 );- creating (220), based on the detected geometry (GM), a digital representation (DR) of at least the detected part of the mining or construction site (302);- determining (230), based on the created digital representation (DR), a drivable area (304) of the mining or construction site (302) in which a mining or construction machine (100) can move around safely; and- determining (240) the geofence (303) as an outer boundary of the determined drivable area (304).

2. The method (200) according to claim 1 , further comprising:- providing (250) the determined geofence (303) to one or more mining or construction machines (100) configured to execute mining operations according to a drill plan (301 ) associated with the mining or construction site (302).

3. The method (200) according to claim 2, wherein, the one or more mining or construction machines (100) comprise one of more in the group of:- an autonomous mining or construction machine; and- a remotely controlled mining or construction machine.

4. The method (200) according to any one of claims 1 -3, wherein the determined geofence (303) is an initial geofence (303init) determined for an initially determined drivable area (304init).

5. The method (200) according to any one of claims 1 -3, wherein the determined geofence (303) is a subsequent geofence (303subseq) determined for a subsequently determined drivable area (304Subseq).

6. The method (200) according to claim 5, further comprising:- comparing (260) the subsequent geofence (303subseq) with a previously determined geofence (303Prev);- detecting (270) that there are one or more differences between the subsequentgeofence (303subseq) and the previously determined geofence (303Prev); and- indicating (280) the detected one or more differences.

7. The method (200) according to any one of claims 1 -6, wherein the detected geometry (GM) comprises information associated with one or more in the group of:- slopes;- inclinations;- changes in inclination- boulders; and- cracks.

8. The method (200) according to any one of claims 1 -7, wherein the at least one airborne sensor (151 ) is mounted on at least one aerial entity (150) in the group of:- a drone;- a helicopter; and- an aircraft.

9. The method (200) according to any one of claims 1 -8, wherein the at least one airborne sensor (151 ) is one or more in the group of:- a light detecting and ranging sensor; and- a photogrammetry sensor.

10. The method (200) according to any one of claims 1 -9, wherein the digital representation (DR) comprises a point cloud.11 . The method (200) according to any one of claims 1 -10, wherein the detection (210) of the geometry (GM) is preformed multiple times during mining according to a drill plan (301 ) associated with the mining or construction site (302).

12. The method (200) according to any one of claims 1-11 , wherein the detection (210) of the geometry (GM) is performed with one of the intervals in the group of:- one detection (210) per 12 hours;- one detection (210) per day; and- one detection (210) per 2 days.

13. The method (200) according to any one of claims 1-12, wherein the mining or construction site (302) comprises a drill bench (302) with a free face (305) at a crest (306) of the drill bench (302), the method comprising:- detecting (211 ) at least the crest (306) by utiliation of the at least one airborne sensor (151 );- creating (221 ), based on the detection (211 ) of at least the crest (306), a digital representation (DR) of at least a part of the drill bench (302) including the crest (306);- determining (231 ) a drivable area (304) such that there is an offset distance (307) between the drivable area (304) and the crest (306);- determining (241 ) the geofence (303) based on the determined drivable area (304).

14. The method (200) according to claim 13, wherein the offset distance (307) is in the interval of 0.5 to 3 meters, or in the interval of 1 to 2 meters.

15. The method (200) according to any one of claims 1 -14, wherein the step of detecting (210) the geometry (GM) is proceeded by the step of:- preparing (205) one or more properties of the mining or construction site (302) such that one or more parameters associated with the mining or construction site (302) are fulfilled.

16. Computer program comprising instructions which, when the program is executed by a computer, cause the computer to carry out the method according to any one of the claims 1 -15.

17. Computer-readable medium (142) comprising instructions which, when executed by a computer, cause the computer to carry out the method according to any one of the claims 1 -15.

18. A system (130) for determining a geofence (303), the system (130) being configured to perform the method according to any one of claims 1 -15.

19. A drilling rig (100) comprising the system (130) for determining a geofence (303) according to claim 18.

20. A drilling operator station (160) comprising the system (130) for determining a geofence (303) according to claim 18.

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