Method and system for manoeuvring a boom of a drill rig

Abstract

The present disclosure relates to a method and system for manoeuvring a boom (203- 205) of a drill rig (200) from a first pose to a second pose, the boom comprising a plurality of joints (231-236), the manoeuvring moving the boom (203-205) from a boom joint configuration of the first pose to a boom joint configuration of the second pose, each boom joint configuration corresponding to a particular setting of the joints A representation of the surroundings of the boom, indicating obstacles, is determined in a 3D coordinate system, and a path from comprising boom joint configurations of intermediate poses is calculated, the path being computed to avoid obstacles. The computing comprises generating a search set comprising boom joint configurations and corresponding poses, identifying boom joint configurations avoiding obstacles, the search set further comprising boom joint configurations calculated for intermediate poses using inverse kinematics, and searching the search set for boom joint configurations forming a path avoiding obstacles from the first pose to the second pose.

Description

[0001] METHOD AND SYSTEM FOR MANOEUVRING A BOOM OF A DRILL RIG

[0002] Technical Field

[0003] The disclosure relates to mining, tunnelling and construction, and more specifically to a method and a system for manoeuvring of a boom of a drill rig. The disclosure also relates to a computer program, a computer-readable medium and a drill rig comprising a system.

[0004] Background

[0005] Rock excavation, such as in mining, tunnelling and construction may be carried out using various techniques, where, e.g., excavation using drilling and subsequent blasting is a commonly used method. The excavation is, in general, carried out in a manner in which drilling is performed in rounds, where a round comprises drilling of a plurality of holes, and where the drilled holes are loaded with explosives to blast the rock. The broken rock is removed, and a new round of holes may be drilled to provide for blasting of a subsequent portion of the rock.

[0006] The rock excavation may be carried out using a mining and / or construction machine such as a drill rig, also known as drilling rig, where a boom comprising joints attach a work equipment, such as a drilling machine, to a carrier. The boom may be utilized to reposition the drilling machine from the location of one hole to another following drilling of a particular hole. The round of holes may be drilled according to a drill plan, and there exist a general desire to automate the drilling of a round of holes, including the manoeuvring of the drilling machine from the location of one hole to another. The use of a boom allows repositioning of the drilling machine without the need to reposition the carrier each time a new hole is to be drilled.

[0007] Furthermore, there exists a general desire to automate operation of mining and / or construction machines; this includes the manoeuvring of the drilling machine from one drilled hole to a new hole to be drilled during the excavation.

[0008] Summary

[0009] An object of the present disclosure is to provide automated manoeuvring from one drilled hole to a new hole during mining. In particular, an object is to provide a method for manoeuvring the boom of a drill rig; autonomously manoeuvring the boom in a reliable manner from a first pose to a second pose while avoiding collision with surrounding obstacles.

[0010] According to a first aspect of the disclosure, it is provided a computer-implemented method for manoeuvring a boom of a drill rig from a first pose to a second pose, the boom being attached to a carrier and comprising a plurality of joints, wherein the manoeuvring comprises moving the boom from a first boom joint configuration of the first pose to a second boom joint configuration of the second pose by manoeuvring at least one of the plurality of joints. Each boom joint configuration corresponds to a particular setting of the joints. The method comprises, prior to manoeuvring the boom from the first pose to the second pose, a determining of a representation of the surroundings of the boom in a 3D coordinate system, the representation of the surroundings indicating obstacles in the surroundings. The method further comprises computing a path for manoeuvring the boom from the first boom joint configuration to the second pose in the coordinate system, the path comprising boom joint configurations representing intermediate poses between the first pose and the second pose in the coordinate system, the path being computed to avoid obstacles. The computing comprises generating a search set comprising a plurality of different boom joint configurations and corresponding poses, the search set indicating boom joint configurations avoiding indicated obstacles, the generated search set further comprising boom joint configurations calculated for intermediate poses between the first pose and the second pose using inverse kinematics, and searching the search set for a subset of boom joint configurations forming a path avoiding obstacles from the first pose to the second pose. Furthermore, the method comprises controlling the joints of the boom to carry out the movement from the first pose to the second pose using the identified subset of boom joint configurations.

[0011] As was mentioned above, there exists a general desire to automate operation of mining and / or construction machines, such as drill rigs, where this automation includes the manoeuvring of the drilling machine from a drilled hole to a new hole to be drilled. When excavating rock, e.g., during mining or tunnelling, an excavation plan is in general utilized, which may comprise to generate drilling patterns prior to or during the excavation, where the drilling patterns are used to drill the rock faces that arise as the excavation progress. The drilling pattern is generated in such a way that subsequent blasting results in a cavity such as a tunnel having the desired profile.

[0012] A drilling pattern may comprise a plurality of holes to be drilled, and the drill rig drilling the holes may comprise a plurality of booms comprising drilling machines effectuating the drilling of the holes. The use of a plurality of booms, and thereby drilling machines, may substantially speed up the drilling process. However, in case the drilling of a drilling pattern is to be carried out autonomously by the drill rig, this may require a large number of manoeuvrings of booms from a completed hole to a subsequent hole to be drilled.

[0013] The manoeuvring of a boom of a drill rig needs to be carried out with precaution to avoid collision with obstacles in the vicinity of the boom. For example, collision with other booms needs to be avoided, as well as collision with other parts of the drill rig, and objects in the surroundings of the drill rig. According to the disclosure, it is provided a method manoeuvring a boom from a first pose, i.e. , the current position of the boom, and hence the drilling machine, to a second pose. The first pose may be the orientation of the drilling machine, and position of a reference, such as a feeder tip, and the first pose may be the pose of the boom when drilling of a hole has been completed, and prior to manoeuvring the boom to a position for drilling a subsequent hole. The second pose may similarly be a pose where the orientation and position of the drilling machine is in place for drilling a subsequent hole.

[0014] A boom in general comprises a plurality of joints, in general more than three, such as five, six, seven or more. This, in turn, means that there in general will exist a plurality of different settings of the joints of the boom that still will result in the boom being set to the desired pose. The manoeuvring of the boom is effected by manoeuvring at least one of the plurality of joints, where each particular setting of the joints represents a boom joint configuration.

[0015] The method utilises a representation of the surroundings of the boom in a 3D coordinate system, where the representation of the surroundings indicating obstacles in the surroundings and computes a path for manoeuvring the boom from the boom joint configuration of the first pose to the second pose in the coordinate system. It is to be noted that the boom joint configuration is inherently known for the pose the boom currently is in, but the second pose may be effected by a plurality of boom joint configurations, and hence it is not known what the resulting boom joint configuration will be. The computed path comprises boom joint configurations representing intermediate poses between the first pose and the second pose, and the manoeuvring from the first pose to the second pose utilizes the intermediate boom joint configurations.

[0016] The computing comprises to generate a search set comprising a plurality of different boom joint configurations and corresponding poses, where the search set indicates boom joint configurations avoiding indicated obstacles. According to the disclosure the generated search set further comprises boom joint configurations calculated for intermediate poses between the first pose and the second pose using inverse kinematics. That is, solutions in terms of boom joint configurations are calculated for various intermediate poses. The search set is searched for a subset of boom joint configurations forming a path avoiding obstacles from the first pose to the second pose, and the joints of the boom are controlled to carry out the movement from the first pose to the second pose using the identified subset of boom joint configurations when a path has been found. For as long as no path has been found from the first pose to the second pose additional boom joint configurations may be added to the search set, until a path is found.

[0017] The present disclosure thereby provides a reliable method for finding a path from a first pose of the boom to a second pose of the boom. The efficiency of the calculations is enhanced in particular by the use of inverse kinematics to calculate boom joint configurations of intermediate poses.

[0018] According to aspects of the disclosure, the method comprises to increase the generated search set of boom joint configurations and corresponding poses in the search set to increase the search set, for as long as no identification of a subset providing a path avoiding obstacles from the first pose to the second pose has been made. That is, further boom joint configurations are added to the search set for as long as no path has been found. The search set may also be repeatedly searched for a subset of boom joint configurations providing a path from the first pose to the second pose. The search set may hence be configured to be increased by adding boom joint configurations, and searches be repeated, until a solution is found. According to aspects of the disclosure, each joint has an individual movement region representing the positions the particular joint can be set. For example, with regard to a hydraulic cylinder the movement region is represented by the various positions to which the hydraulic cylinder can be set along the stroke length of the hydraulic cylinder. With regard to a rotation motor, the movement region can be represented by the allowable rotation of the rotation motor, such as one or more rotations, or part of a rotation. The difference in joint setting of any of the plurality of joints between adjacent boom joint configurations in the search set is less than a predetermined difference in joint settings. It can hence be determined a difference in positions between boom joint configurations that is sufficiently small to ensure that collision may not occur between adjacent boom joint configurations.

[0019] According to aspects of the disclosure the predetermined difference in joint setting is determined at least partly based on the movement region of at least one of the plurality of joints, a maximum speed of at least one of the plurality of joints, a maximum acceleration of at least one of the plurality of joints.

[0020] According to aspects of the disclosure, the method further comprises, when a boom joint configuration is added to the search set, one or more from: stochastically selecting the boom joint configuration to be added, utilizing inverse kinematics algorithm to calculate a boom joint configuration for an intermediate pose between the first pose and the second pose, determining whether the calculated boom joint configuration avoids obstacles indicated in the representation of the surroundings.

[0021] The boom joint configurations can be stochastically added since it is not known in which way the boom should move according to the yet not known path. Hence boom joint configurations may be added that cover boom motion in various directions. Still restrictions may be imposed in that the stochastic selection may be configured to start from a particular boom joint configuration, although this selection, too, may be stochastic in that the selection may be from any boom joint configuration already present in the search set. The stochastic selection may also be restricted in regard of allowable differences in boom joint position in relation to the boom joint configuration from which the selection is started. For example, the selected boom joint configuration may only have a particular number of joints with a changed joint position. Alternatively, or in addition, a change in joint setting of the stochastically selected boom joint configuration in relation to a boom joint configuration already present in the search set may be required to at most be a predetermined maximum change.

[0022] According to aspects of the disclosure, the computing further comprising use of a Hybrid Forward Rapid exploring Random Tree (RRT) algorithm to generate the search set in the form of a search tree of nodes through iteration, each node representing a boom joint configuration and corresponding pose. Hence the calculations may be based on an RRT algorithm, but where a hybrid variant is used to speed up the calculations.

[0023] Each iteration of the RRT algorithm may comprise at least one of: stochastically selecting a boom joint configuration and determining a corresponding pose; utilizing an inverse kinematics algorithm to calculate a boom joint configuration for an intermediate pose between the first pose and the second pose; determining whether a selected and / or calculated boom joint configuration avoids obstacles indicated in the representation of the surroundings; and searching the search tree for a path from the first pose to the second pose avoiding obstacles.

[0024] Hence, the calculations may be based on a commonly used algorithm, the RRT algorithm, however with the additional feature of utilizing an inverse kinematics algorithm to calculate boom joint configurations for intermediate poses between the first pose and the second pose to find a path from the first pose to the second pose more efficiently.

[0025] According to aspects of the disclosure, the search tree of nodes is searched for a path to the at least one intermediate pose when inverse kinematics have been utilized to calculate a boom joint configuration for at least one intermediate pose. The intermediate pose may then be used as starting point for continued search in the search tree of nodes when a path to the at least one intermediate pose has been found, following further addition of boom joint configurations to the search tree. In this way the continued search can continue from the intermediate pose, and thereby possibly reduce searches in boom motion directions that will give rise to longer, less efficient paths.

[0026] According to aspects of the disclosure, a search is configured to start starting from a node reached during a previous search, and that represents a nearest pose to the particular pose, when searching the search tree of nodes towards a particular pose. The nearest pose may be calculated in the representation of the surroundings using conventional methods. This, too, may make the search more efficient, since boom joint configurations, and / or intermediate poses, to be added to the search set may be selected starting from the node in the search tree that is closest to the target pose.

[0027] According to aspects of the disclosure, a first Hybrid Forward RRT algorithm is utilized to generate a first search tree of nodes through iteration from the first pose towards the second pose, and a second Hybrid Forward RRT algorithm is used to generate for generating a second search tree of nodes through iteration from the second pose towards the first pose. Both search trees are then searched for a path from the first pose to the second pose avoiding obstacles, and the paths can be combined when a same boom joint configuration occurring in both search trees is identified. This may further increase the efficiency of the algorithm.

[0028] According to aspects of the disclosure, the representation of the surroundings is generated utilizing one or more from a tunnel model and / or a rock face model being computed utilizing one or more of: a drill plan contour; a theoretical tunnel profile; a scanning of the surroundings, e.g., utilizing LIDAR; a plane with a safety distance from the theoretical rock face; geometries of the drill rig. The representation of the surroundings may hence be generated using one or more conventional methods for generating representations of the surroundings.

[0029] According to aspects of the disclosure the geometries of the drill rig comprises one or more from: current configuration of one or more booms; other machine geometries, such as jacks, cabin and carrier. Hence, it can be ensured that a boom does not collide with other parts of the drill rig. Furthermore, obstacles in the representation of the surroundings may comprise surrounding rock walls, and other obstacles being present in the surroundings of the machine, where such objects may be detected using scanning as above or from a model representation of the surroundings. According to aspects of the disclosure, joint position settings of at least one of the plurality of joints is restricted to a portion of the movement space of the at least one joint when reaching the second pose. In this way it can be ensured that joints are not set in unfavourable settings when the second pose is reached.

[0030] According to aspects of the disclosure one of the plurality of joints control a feeder displacement, the constraints comprising to ensure a minimum remaining feeder displacement when reaching the second pose. In this way it can be ensured that the feeder, following the manoeuvring to the second pose, can be further pushed towards the rock in case rock contact has not been made.

[0031] According to aspects of the disclosure, the method further comprises, prior to controlling the joints of the boom to carry out the movement from the first pose to the second pose subjecting the computed path for manoeuvring the boom from the first pose to the second pose to a smoothening operation comprising at least one of: repeatedly searching a shorter path between boom joint configurations in the computed path and replacing the path with the shorter path when possible; imposing limitations on maximum speed of motion, and / or acceleration, of one or more of the plurality of joints when manoeuvring the boom according to the path.

[0032] The smoothening may take two different points along the path, and then attempt to find a shorter path between boom joint configurations along the path, while still ensuring that collision does not occur. This may be repeated for as long as the path is becoming shorter. This will inherently also reduce or remove, e.g., a jagged appearance of the path so that instead a smoother path, and thereby joint motion, is obtained.

[0033] The boom joint configurations being selected for smoothening may be stochastically selected, and the stochastic selection may repeatedly be performed. According to embodiments of the disclosure the smoothing operation is carried out using a parabolic shortcutting algorithm.

[0034] According to aspects of the disclosure, the first pose and the second pose are determined in relation to a reference point, the reference point being a point in a local coordinate system of the drill rig, and / or a reference point in a coordinate system of the surroundings of the drill rig.

[0035] According to aspects of the disclosure, the boom carries a work equipment such as a drilling machine, the manoeuvring of the boom from the first pose to the second pose manoeuvring the work equipment from the first pose to the second pose. Hence the first and second pose may comprise poses of a work equipment such as a drilling machine.

[0036] According to a further aspect, the disclosure relates to a system for manoeuvring a boom of a drill rig. It will be appreciated that all features described for the method aspects of the disclosure are applicable also to the system aspects of the disclosure. Also, the system and its aspects have advantages corresponding to the advantages discussed above with regard to methods. The disclosure also relates to a drill rig comprising a system of such kind.

[0037] Further advantageous embodiments of the disclosure will emerge from the detailed description.

[0038] Brief description of the drawings

[0039] Fig. 1 schematically illustrates a partly excavated tunnel;

[0040] Fig. 2A schematically illustrates an exemplary drill rig comprising a plurality of booms;

[0041] Fig. 2B illustrates a boom of the drill rig in Fig. 2A more in detail;

[0042] Fig 3 illustrates a thread model for a boom according to fig 2B;

[0043] Figs. 4A-B schematically illustrates a method according to aspects of the disclosure;

[0044] Fig. 5A schematically illustrates a resulting path according to aspects of the disclosure;

[0045] Fig. 5B schematically illustrates the path of Fig. 5A following smoothing according to aspects of the disclosure. Detailed description

[0046] Embodiments of the disclosure will be exemplified in the following with reference to examples relating to excavation of a tunnel to be excavated in rock. The tunnel may be any kind of tunnel for any suitable use, and, e.g., comprise a tunnel forming part of a mine, or a tunnel for road or railway transport.

[0047] Fig. 1 schematically illustrates a tunnel, where the tunnel is represented by a tunnel line TL, which essentially is defined by points 107 which may be interconnected. The extension of the tunnel may be obtained by interconnecting the tunnel line points 107. The disclosed section of the tunnel to be excavated represents a section of the tunnel some n tunnel line points 107 into the tunnel. The tunnel line points are defined in a 3D coordinate system being used in the excavation, e.g., a global coordinate system, or a coordinate system local to the area of excavation, so that the desired tunnel can be excavated in conformity with the pre-planned tunnel plans.

[0048] Fig. 1 also illustrates the desired outline 101 of the tunnel as seen from above. In addition, the actual rock walls 102 of the already excavated portion of the tunnel are shown, including the rock face 103 about to be drilled as the excavation progress.

[0049] Any suitable number of tunnel line points may be used in the representation of the tunnel, where the number, e.g., may depend on the length of the tunnel to be excavated, and any suitable, constant or varying, distance between the tunnel line points may be used, e.g., in dependence of curvature. For example, the distance between tunnel line points may represent the length of the longest holes to be drilled during a round for subsequent blasting, but any other suitable distance may also be utilised. The length of the holes to be drilled may, e.g., correspond to the length along a feed beam that a drilling machine may slide, and e.g., be in the order of 0-10 metres.

[0050] In order to obtain a representation of the tunnel alignment, e.g., a representation of the desired tunnel cross section, in the following denoted tunnel contour, or tunnel profile, may be defined for each tunnel line point, e.g., in a plane perpendicular to the tunnel line TL. The tunnel contours of different tunnel line points may be defined in a same plane but may also be defined in different non-parallel planes. An example of a tunnel contour 101 is disclosed in Fig. 2, exemplifying a tunnel contour 221. The interconnected tunnel line points together with associated tunnel contours, which may vary in shape from one tunnel line point to another can be used to form a 3D volume through interpolation representing the tunnel and which is being defined in a coordinate system to allow excavation at a desired location. Consequently, the tunnel is represented by tunnel contours distributed along the tunnel line TL representing the desired extension of the cavity to be excavated.

[0051] Tunnel / cavity excavation of this kind often involves generation of a drill plan, in the following denoted drilling pattern, for drilling of a set, or round, of drill holes in a rock face for subsequent blasting. The drilling pattern defines the holes to be drilled, e.g., in the coordinate system of the tunnel, and may define position, length and direction for each hole. Holes having different diameters may also be drilled, and hence a hole diameter may be defined by the drilling pattern as well. Following drilling of a round, the drilled holes are charged with explosive material that is detonated following drilling and charging of the holes of the drilling pattern.

[0052] Fig. 2 illustrates an exemplary movable rock drill rig 201 that may be utilised, e.g., in tunnel excavation of a tunnel according to Fig. 1. The rock drill rig 201 is an underground drill rig and is shown in position for drilling a round of holes in a rock face 202 during tunnel excavation, e.g., along the tunnel line TL of Fig. 1 .

[0053] As can be seen in Fig. 2, the rock drill rig 201 according to the disclosed example is provided with three booms 203-205, each of which carrying a drilling machine 206-208 via feed beams 209-211. Accordingly, the disclosed rock drill rig 201 may drill up to three holes at a time. Drill rigs of the disclosed kind are known per se. The drilling machines 206-208 are, in this example, hydraulically driven and power supplied from one or more hydraulic pumps 212, which in turn are driven by one or more electric motors and / or combustion engines 213, also in a manner known per se. The drilling process may be controlled by an operator from a cabin 215.

[0054] The drill rig 201 further comprises a rig control system comprising at least one control unit 214, which controls various of the functions of the drill rig 201 , e.g., by suitable control of various actuators / motors / pumps etc. Drill rigs of the disclosed kind may comprise more than one control unit, where each control unit, respectively, can be arranged to be responsible for different functions of the drill rig. Aspects of the disclosure may be implemented using one or more such control units.

[0055] The drill rig 201 is arranged to be repositioned as excavation progresses and comprises, according to the present example, wheels 216, 217 for allowing drill rig movability. Crawler drives or other suitable means may alternatively be used to allow manoeuvring of the drill rig 201 .

[0056] Fig. 2 hence discloses a drill rig that following a previous blast and clearing of broken rock has been moved forward in the excavating direction, i.e. , along the tunnel line TL, towards the rock face 202 resulting from the previous blast, and the drill rig 201 has been positioned for drilling the subsequent round for blasting of the next section of the tunnel / cavity to be excavated. In order to correctly excavate rock according to the predetermined tunnel alignment, the exact position of the rock drill rig 201 in the prevailing coordinate system must be determined. This can be accomplished in various ways and, for example, by aligning one of the feed beams, e.g., feed beam 211 to a laser beam of a total station (not shown), where the position of the total station in turn has been established using fixed points. Various other means for positioning the drill rig also exist as is known per se. For example, the drill rig may be provided with fixed points, which may be used to position the drill rig using, e.g., a total station, where the rig fixed points are also defined in the coordinate system of the drill rig, so that thereby, e.g., the position of a feed beam may be determined in the coordinate system of the tunnel.

[0057] The drill rig 201 in general comprises a local rig coordinate system, and through the use of the local drill rig coordinate system the position of the drill rig in the global coordinate system can be determined using the location of the feed beam in the drill rig coordinate system and the location of the feed beam as determined in the coordinate system of the tunnel.

[0058] As mentioned before, prior to drilling of the rock face 202 commences, a drilling pattern may be generated to be drilled prior to blasting the current rock face 202. The positions of the holes to be drilled on the rock face are schematically illustrated by “x” markings in Fig. 2A, where these positions are determined by the drilling pattern. The drilling pattern to be used may be determined prior to the excavation of a tunnel commences, e.g., in a planning centre, where the holes are planned such that the subsequent blasting as close as possible corresponds to the desired cavity to be excavated. The drilling pattern may also be generated or adapted during ongoing excavation.

[0059] The drilling of the rock face according to the drilling pattern may be configured to be carried out automatically. That is, movement of the booms with associated drilling machines may be controlled by the rig control system. As is schematically exemplified in Fig. 2A, a drilling pattern may comprise a large number of holes to be drilled, where these holes may have different directions according to the drilling pattern. According to the present example, the drill rig comprises three booms and hence drilling of the holes can be divided among the booms so that all booms may carry out drilling concurrently in order to reduce the overall time of drilling that is required to complete the drilling pattern. Each time a hole has been drilled, and drilling of a new hole is to be commenced, the boom with feeder and drilling machine is relocated to the start position of the next hole to be drilled, and the feeder is also aligned with the defined drilling direction of the particular hole that is about to be drilled.

[0060] Since the drill rig, according to the present example, comprises three booms that may operate in overlapping workspaces it is important that collision with other booms, or the carrier, or other objects in the surroundings of the drill rig, is avoided. In general, a boom of the drill rig has a number of degrees of freedom when it comes to possible movement as will be exemplified with reference to Fig. 2B.

[0061] In addition, according to the illustrated example, the drill rig of Fig. 2A represents a multiple manipulator environment, where the manipulator arms (booms) constitute time- varying obstacles to each other, since the booms will change their location in relation to the other booms as time progress, and the booms are being manoeuvred to new holes to be drilled. This renders a collision-free boom motion path planning more complicated and time-consuming to calculate.

[0062] This is further emphasized by the various joints that a boom may comprise, and which will result in an over-determined system when it comes to the setting of the joints for a particular pose of the feeder, e.g., specified as the position of the feeder tip and an angular direction of the feeder in the coordinate system being used. The consequence of this over-determination is that there may exist a substantial number of, or even an infinite number of, possible boom joint settings that will result in the same pose of the feeder. This further complicates the calculations when determining whether movement of one boom from one hole to another will cause a collision, and also complicates calculations required to find a path to the hole to be drilled.

[0063] Fig. 2B illustrates the boom 203 of the drill rig 200 in the figure 2A more in detail. It is to be noted that the boom of Fig. 2B is only exemplary, and that the various different kinds of booms exist for drill rigs of the kind illustrated in figure 2A. It is also to be noted that the disclosure is applicable for various different kinds of drill rigs. The boom 203 according to Fig. 2B comprises a front tripod 231 having hydraulic cylinders attaching the boom to the carrier. The hydraulic cylinders control the motion of the boom up / down and laterally. The boom 203 further comprises a boom extension joint 232 that may be used to extend and retract the boom.

[0064] The boom further comprises two rotation joints 233 (feeder rotation), 234 (feeder swing), which together with a joint 235 (feeder tilt) can be used to control the feeder 209in different directions. The rotation joints 233, 234 are, in this embodiment, arranged at substantially right angles in relation to each other, wherein the rotation joint 233 is fastened to the boom to thereby allow rotation about the longitudinal axis of the boom 203. Rotation by means of rotation joint 233 therefore results in the feeder being rotated about the longitudinal axis of the boom. The rotation joint 234 is arranged at a right angle with respect to the rotation joint 233, and thereby allows rotation of the feeder about a, in relation to the boom, transversal axis. The feeder can also be rotated about the feeder tilt joint 235. The figure also illustrates feeder displacement 236.

[0065] Fig. 3 illustrates a kinematic model describing boom kinematics of the boom disclosed in Fig. 2B. As can be seen, and according to the above, the boom comprises five degrees of freedom with regard to rotation, i.e. , Z1 boom swing, Z2 boom lift, Z4 feeder rotation, Z5 feeder swing and Z6 feeder tilt. Furthermore, the disclosed boom comprises joints providing two degrees of freedom relating to translation. This is joint Z3, i.e., the boom can be prolonged / shortened in a telescopic manner and Z7 that provides for feeder displacement in relation to the distal end of the boom. The drilling machine may also be displaceable in relation to the boom. The use of a displaceable feeder and / or drilling machine, has the result that the feeder must not continuously be moved forward as the drilling progress. These various degrees of freedom provide for, as stated, multiple or even infinite, possibilities of particular joint settings, i.e. boom joint configurations, for one and the same pose of the feeder in terms of position and direction. A joint Zi of the joints Z1 -Z7 can be seen as the i:th free kinematic joint along a kinematic chain represented by the joints Z1-Z7.

[0066] According to the disclosure it is provided a method for determining the boom motion to be carried out when repositioning the boom from one hole to another, where the method also ensures that collision with other objects will not occur, and in particular that provides a method for performing the required calculations in a manner that may faster achieve the desired result.

[0067] There exists a general desire to carry out the required calculations as quickly as possible, since the calculations need to be performed each time the boom is moved and may need to be carried out simultaneously for more than one boom.

[0068] Although a simplest way of dividing the drilling of the holes of the drilling pattern would be to divide the workspace set forth by the drilling pattern into separate portions being assigned to the booms, this may not provide an optimal solution. Instead, optimal use of the drilling machines in general require that the booms operate in overlapping areas during the drilling of the drilling pattern. For example, a boom may break down during drilling, rendering it necessary to reassign holes of the faulty boom to other booms. The drilling of the holes may also take different amounts of time to complete, so that reallocation of holes of a non-finished boom to a finished boom is carried out to complete the drilling pattern more quickly. The booms may also be configured to operate, in particular be manoeuvred in, overlapping workspace throughout the drilling of a drilling pattern.

[0069] Figure 4A illustrates a method 400 according to a first exemplary aspect of the disclosure. The method starts in step 401 , where a representation of the surroundings of the drill rig is determined. The representation of the surroundings may be determined in various different ways. According to the present example, a plurality of representations, denoted “spaces” may be utilized for calculation purposes, where these spaces are representations of the surroundings in a 3D coordinate system, the spaces still relate to the same physical area. The different spaces may be defined to include different objects. For example, obstacles need not be present in all spaces being utilized. According to embodiments of the disclosure, a single representation may instead be utilized in the calculations.

[0070] A representation of the surroundings of the drill rig may be generated, e.g., using a drill plan contour, such as drill plan contour 221 in Fig. 2A, and / or a theoretical tunnel profile, e.g., represented according to Fig. 1. The representation may also be generated using distance measurements to surrounding objects, where distances may be determined, e.g., by scanning using LIDAR. A model of the drill face may also be utilized, as well as a plane that is determined with a safety distance to the theoretical rock face to be drilled. Theoretical collision geometries from current configuration of booms and other collision geometries such as jacks and cabin may also be utilized in the determination. The determination of a representation in a 3D coordinate system in this manner is known per se. these collision geometries may, e.g., be represented by simple geometrical shapes such as boxes, cylinders etc. to facilitate calculations when determining whether a collision will occur.

[0071] The coordinate system being used may be a coordinate system being used in the excavation, which may be a global coordinate system or a coordinate system local to the area of excavation, so that the desired tunnel can be excavated in conformity with the pre-planned tunnel alignment, and / or the local rig coordinate system described above, where still booms etc. are positioned in a known relationship with regard to the global coordinate system.

[0072] According to examples below, one or more of the following spaces are utilized in the calculations.

[0073] Workspace - The workspace, or W-space in short, is a 3D space (coordinate system) that surrounds the boom. This space comprises the various obstacles that may be situated in this space, such as parts of the boom itself, other booms attached to the drill rig, the carrier, tunnel walls, and various other objects that may be present in the vicinity of the drill rig. These objects may be defined by knowledge that the drill rig has about itself, i.e. , the presence of the carrier, and the extension of the booms in relation to the carrier, and also distances to surrounding tunnel walls, which can be determined, for example, through measurement in a representation of the surroundings, or through measurement using sensors onboard the machine, such as laser / LIDAR sensors. The geometry being used to describe the various components may be simplified calculations where, e.g., a part of a boom may be defined by a geometrical object such as a cylinder or rectangular cuboid. The W-space may be represented as one or more geometric 3D models of the surrounding objects, hence indicating the obstacles that a boom, during motion, may risk colliding with.

[0074] Task space - According to embodiments of the disclosure the calculations also utilize a boom task space, or T-space, which is a 3D space (coordinate system) in which the boom operates. A point (which can also be referred to as a pose or frame, F) in T- space, x = [tx tytz rxryrzrw]Tspecifies a frame on, according to the present example, the special Euclidian group SE(3), where [tx tyfz]Tis the coordinates of the frame’s origin and [rxryrzrw]Tis a unit rotation quaternion describing the frame’s orientation in 3D space, with respect to some frame of reference Fret. Fret can be represented by any point on the drill rig, as well any other point in the mine. That is, the pose, i.e., orientation of the feeder can be expressed in this manner.

[0075] Configuration space - boom configuration space, or C-space, can be defined as a Euclidian space of boom configuration vectors q e Rndof. Element q, represents a current position (extension or angle, depending on the type of joint, rotation or translation) of the / :th free kinematic joint along the kinematic chain (e.g., joint Zi of the joints in Fig. 3) that describes the boom kinematics, ndof is the number of degrees-of- freedom of the boom, i.e., the number of movable kinematic joints.

[0076] A movable kinematics joint may be actuated by one, or several, hydraulic actuators. For example, with regard to the boom of Fig. 2B, boom lift may be controlled by a pair of hydraulic cylinders, whereas, e.g., feeder rotation and feeder swing are each controlled using a rotation motor, respectively.

[0077] Following the determination of the representation of the surroundings in step 401 , a path is calculated between the first pose and the second pose, step 402. According to the disclosure, it is provided a method for calculating the movement of a boom when the boom is to be moved from a first boom joint configuration of the first pose of the feeder to a second boom joint configuration of the second pose of the feeder by manoeuvring at least one of the plurality of joints. As was mentioned above, each boom joint configuration corresponds to a particular setting of the joints. A movement of the boom from the first pose to the second pose will encompass a movement through a plurality of intermediate boom joint configurations, where each intermediate boom joint configuration will give to an intermediate pose of the boom. Each intermediate pose is hence a movement of the boom, and it will be necessary to verify that each intermediate pose does not give rise to a collision with an obstacle.

[0078] In step 402, a plurality of boom joint configurations are determined, where this may be carried by stochastically determining boom joint configurations, and the corresponding pose is also calculated for each of these boom joint configurations, and it is also determined whether the boom joint configuration (the resulting pose) will give rise to a collision, in which case the boom joint configuration is discarded from manoeuvrable alternative. The plurality of boom joint configurations that do not give rise to collision, and corresponding poses, establishes a search set, from which a possible motion from the first pose to the second pose through intermediate boom joint configurations is then searched. Boom joint configurations that do give rise to collision may still be stored, so that these need not be checked again. The corresponding pose of a boom joint configuration can be calculated using straight-forward forward kinematics, that is, it is simply calculated what will be the resulting pose when setting the joints according to the boom joint configuration.

[0079] With regard to collision avoidance of objects, such as booms that operate in an overlapping workspace, this is a well discussed topic in robotics. There exist various methods in the art for performing such calculations where any suitable solution may be utilized. For example, a collision detector that utilizes geometric shapes to represent, e.g., booms may be used, where collision can be detected if the geometrical shapes overlap or comes within a minimum distance from each other. The collision detection is therefore not discussed further.

[0080] Further, since it is not known beforehand what the resulting pose is from a particular boom joint configuration, it may be required to generate a search set comprising a large number of boom joint configurations before any path from the first pose to the second pose can be found, where added boom joint configurations can be defined by a maximum difference in joint setting of one or more joints in relation to an existing boom joint configuration in the search set, and where the first boom joint configuration in the search set may be the boom joint configuration of the first pose. With regard to the difference in joint setting, each joint has an individual movement region representing the positions the particular joint can be set. For example, with reference to Fig. 2B, boom swing and boom lift are restricted by the stroke lengths of the hydraulic cylinders accomplishing the boom swing and boom lift. Also, boom extension has a certain stroke length, and this applies to feeder displacement as well. Similarly, rotation motors 233, 234 have a movement region which may be part of a full rotation, or a full rotation, or more than a full rotation, where the movement region can be represented by the allowable total rotation of the rotation motor. The difference in joint setting may be, e.g., a maximum difference in position of the setting of a hydraulic cylinder, or other joint, such as a rotation joint. This difference may be determined, e.g., based on a sampling rate being used, and / or a maximum speed of at least one of the plurality of joints, and / or a maximum acceleration of at least one of the plurality of joints.

[0081] The search set will, due to the above, give rise to poses that go in various different directions in relation to the current pose of the boom. When the search set has grown to some suitable extent by adding boom joint configurations, a search can be performed in order to try to find a path from the first pose to the second pose. For as long as no path is found, further boom joint configurations, and corresponding poses, are added to the search set, which may regularly be searched for a solution.

[0082] According to the disclosure, in order to increase the speed of the search for a path from the first pose to the second pose, in addition to adding boom joint configurations starting from a previous boom joint configuration, it is also added boom joint configurations generated by determining an intermediate pose between the first pose and the second pose, and calculating a corresponding boom joint configuration for this pose that is added to the search set.

[0083] It is to be noted in this regard, that the resulting boom joint configuration of a pose of the feeder that is, e.g., very close to the first pose of the feeder still may give rise to a boom joint configuration that is very different from the boom joint configuration of the first pose. This is because, as was mentioned, the plurality of joints result in an overdetermined equation system, where this overdetermined equation system is solved utilizing inverse kinematics. This solving using inverse kinematics thereby calculates a resulting boom joint configuration from a particular pose, where the pose is given by a position and direction, e.g., of the feeder.

[0084] However, given the overdetermination there are a large number of different boom joint configurations that will give rise to the same pose, and the calculations of the reverse kinematics may provide any of these poses as a solution. Consequently, when generating the search set of boom joint configurations, inverse kinematics may be utilized not only for a plurality of intermediate poses, but also a plurality of times for a same pose, since the inverse kinematics may give rise to different solutions each time the equation system is solved. Still the use of intermediate poses and inverse kinematics provide a solution that may have a substantial impact on the time it takes to find a solution that allows collision free manoeuvring from the first pose to the second pose.

[0085] The search set may be searched regularly during the adding of boom joint configurations to the search set, where boom joint configurations, and corresponding poses can be added for as long as no solution is found, and when a path has been found between the first pose and the second pose, the joints of the boom are controlled in step 403 to carry out the actual movement from the first pose to the second pose using the identified subset of boom joint configurations.

[0086] The method of Fig. 4A provides a solution that gives rise to a collision free path between the first pose and the second pose. This path, however, may comprise a plurality of intermediate boom joint configurations, and also movement of the boom back and forth in various different directions. Hence, although the method of Fig. 4A provides an adequate solution, the result may give rise to a jerky behaviour when manoeuvring the boom. The resulting path may therefore be subjected to smoothing. This is discussed further below.

[0087] Another method 410 according to aspects of the disclosure is shown in Fig. 4B, where also a particular algorithm is exemplified as being used, although the algorithm comprises additional features in relation to prior art algorithms of the particular kind.

[0088] In particular, a Rapid exploring Random Tree (RRT) algorithm is utilized to generate the search set, and search the search set for a solution, but where the RRT algorithm has been amended according to the below. In step 411 , similar to Fig. 4A, a representation of the surroundings is generated, where the representation may comprise the various spaces, and according to the present example, C-space, T-space and W-space as exemplified above are utilized. In step 412 a path between the first pose and the second pose is calculated using a Hybrid Forward RRT algorithm, where the steps of the algorithm may be as follows:

[0089] The Hybrid Forward RRT algorithm is, according to the present example, utilized to generate a search tree for finding a path from the current boom configuration, ( current, of the first pose, Xcumnt, to the second pose, Xj.

[0090] This may be performed by iterating the algorithm, where each iteration may comprise one or more from a number of actions.

[0091] An iteration may comprise an exploration, or sampling, in C-space. That is, a new sample is taken that represents a new boom joint configuration. The resulting pose of this boom joint configuration, which is calculated through forward kinematics, is then checked for collision in H / -space, where the collision detection checks that no part of the boom will collide with any obstacle present in W-space. A boom joint configuration that does not result in collision is stored in the search tree that is used for finding a path to the second pose Xj. Boom joint configurations that does give rise to a collision may also be stored to prevent such configurations from being tested again.

[0092] An iteration may also comprise an exploration in T-space using, e.g., a Jacobian based inverse kinematics (IK) algorithm. That is, a pose of the boom may be sampled, where the pose may be located between the resulting pose of the initial boom joint configuration, and the target pose, i.e. , second pose Xj. As discussed above, inverse kinematics, such as, for example, a Jacobian based IK algorithm, may be utilized in this regard to solve for a boom joint configuration giving rise to the sampled pose. The resulting boom joint configuration also needs to be sampled in W-space to determine whether or not it will give rise to collision. Again, a boom joint configuration that does not give rise to collision is added to the search tree, while boom joint configurations giving rise to collision are also kept track of. With regard to the sampling in T-space, sampling may be carried out a plurality of times also for a same pose, since inverse kinematics may give rise to different solutions due to the overdetermination of the equation system. In addition, or alternatively, the inverse kinematics may be utilized to determine whether any boom joint configuration in the search tree is a solution to the sampled pose in T-space. When it is possible to move to a pose located between the initial boom joint configuration and the target pose the search may continue from this point the next time a search is performed in the search tree.

[0093] The search tree, or trees, therefore comprises both boom joint configurations in C- space, as well as poses in T-space. The search tree will hence represent positions in W-space in which it is free to move.

[0094] Iterations of the algorithm may also comprise an attempt to reach the T-space target, i.e. the second Xj, starting from the nearest point [qn, Xn] in search tree that so far has been reached. Initially the search to reach the T-space target will be the initial boom joint configuration, but as the iterations progress the search will start to reach positions towards the second pose. The search may be configured to be carried out, e.g., each time a predetermined number of boom joint configurations has been added to the search tree. The search hence need not be carried out each time a boom joint configuration has been added to the search tree. The search may be carried out using accurate Jacobian based IK algorithm.

[0095] The search of the search tree may further comprise to consider possible constraint tasks CT, where the constraint tasks may comprise constraints regarding desired joint positions, and also constraints regarding joint positions that are not to be accepted for the target pose. For example, it may be desirable that the final setting of one or more joints are restricted to be within predetermined intervals of the movement region of a joint, or that not only collision is avoided, but that also a predetermined safety distance is maintained to objects such as other booms that the boom may collide with. Such constraint tasks may, e.g., comprise that the feeder is not fully extended, since this would prevent further movement towards the rock to be drilled. There may also be a preference regarding the movement margin of the feeder extension joint. There may also be a preference that the feeder is not rotated using the rotation joint 233 to certain positions.

[0096] The algorithm keeps track of where the algorithm has been sampling in C-space and in T-space, and also keeps track of where it is possible to move, and where it is not possible to move. As explained, both C-space and T-space are sampled, and the algorithm is iterated until the generated tree provides for a collision free path from the initial pose to the end (second) pose of the boom.

[0097] However, as was mentioned above, although this results in a collision free path from the initial pose to the desired pose, it is likely that the path will consist of a path of boom joint configurations that may be very jagged.

[0098] This is because the described algorithm provides a path but does not take into account whether boom and / or joint motions will go back and forth during the manoeuvring from the initial pose (boom joint configuration) to the end pose. The resulting path may also comprise a large number of boom joint configurations, where the distance between boom joint configurations may be determined, e.g., by the speed of the fastest boom joint, and / or the sample time of boom joints where such factors may be used to determine a suitable allowable difference between joint settings of adjacent boom joint configurations.

[0099] Fig. 5A schematically illustrates a resulting path according to step 412, where only the feeder is shown, and where each dot between the two illustrated feeder poses 501 (initial pose) and 502 (target pose) indicate an intermediate pose of the feeder tip, where in addition each intermediate pose may have different general directions of the feeder. 503 represents an obstacle.

[0100] Given the likely jagged appearance of the resulting path, as illustrated in Fig. 5A, the collision free path is therefore smoothened, step 413, still with the requirement that a collision free trajectory is obtained, but where it is desired to smoothen the trajectory to avoid, e.g., sudden changes in direction of movement of the boom, such as by joint motion changing direction during the boom motion. Various techniques may be used in this regard, and, for example, a parabolic short cut smoother may be used. Alternatively, any other suitable smoothing algorithm may be utilized.

[0101] The parabolic short cut algorithm randomly picks two points along the found path, such as points 504, 505, and attempts to generate a short cut between these points that still does not give rise to a collision by checking this. The algorithm performs this for a large number of randomly selected positions, which will generate a more and more smoothened path to obtain an overall smoothened path. Furthermore, when generating a short cut between two points along the path the algorithm also calculates speeds of accelerations of the joints when carrying out a motion between the two points for which the path is smoothened, where the maximum velocity and acceleration of each joint is respected.

[0102] The algorithm also calculates the manner in which a joint is to be accelerated, e.g., from standstill so that smooth accelerations and decelerations of the joints are obtained. In general, the most efficient manner to manoeuvre from one boom joint configuration to another boom joint configuration is to manoeuvre each joint from the present position to the corresponding position of the subsequent boom joint configuration, provided that this does not give rise to collision. The smoothening may thereby remove various boom motions that would cause joints to go back and forth. Fig. 5B illustrates an exemplary result of the path of Fig. 5A following smoothing. The calculated joint velocities and accelerations are then applied, step 414 in Fig. 4B, in the control, and the joints are controlled to effectuate the manoeuvring of the boom from the first pose to the second pose along the smoothened path, step 415.

[0103] According to embodiments of the disclosure, a further search tree is utilized in the finding of a path from the first initial pose to the final pose, where a Hybrid Bidirectional RRT algorithm may be used to obtain better performance and robustness. Hence, according to such embodiments, two search trees are utilized instead of one. That is, similar to above, one search tree is used to find a solution from the current position ( / current towards the target pose Xj. In addition, a second search tree is used in the opposite direction, i.e. , a search tree from the target pose xy towards the initial boom joint configuration qCurrent. A path may then be found when a boom joint configuration that can be reached from both starting positions can be found. This may generate a faster solution to finding a path between the initial pose and the target pose.

[0104] Finally, the disclosure is not limited to the above-described aspects, but the disclosure relates to, and encompasses, all of the different aspects that are included within the scope of the independent claims.

Claims

Claims1 . A computer-implemented method for manoeuvring a boom (203-205) of a drill rig (200) from a first pose to a second pose, the boom being attached to a carrier (201 ) and comprising a plurality of joints (231-236), wherein the manoeuvring comprises moving the boom (203-205) from a first boom joint configuration of the first pose to a second boom joint configuration of the second pose by manoeuvring at least one of the plurality of joints, each boom joint configuration corresponding to a particular setting of the joints, the method comprising, prior to manoeuvring the boom from the first pose to the second pose: determining a representation of the surroundings of the boom in a 3D coordinate system, the representation of the surroundings indicating obstacles in the surroundings, computing a path for manoeuvring the boom from the first boom joint configuration to the second pose in the coordinate system, the path comprising boom joint configurations representing intermediate poses between the first pose and the second pose in the coordinate system, the path being computed to avoid obstacles, the computing comprising: generating a search set comprising a plurality of different boom joint configurations and corresponding poses, the search set indicating boom joint configurations avoiding indicated obstacles, the generated search set further comprising boom joint configurations calculated for intermediate poses between the first pose and the second pose using inverse kinematics, and searching the search set for a subset of boom joint configurations forming a path avoiding obstacles from the first pose to the second pose, the method further comprising: controlling the joints of the boom to carry out the movement from the first pose to the second pose using the identified subset of boom joint configurations.

2. A method according to claim 1 , further comprising, pending identification of a subset providing a path avoiding obstacles from the first pose to the second pose: increasing the generated search set of boom joint configurations andcorresponding poses in the search set to increase the search set, repeatedly searching the search set of boom joint configurations for a subset providing a path from the first pose to the second pose.

3. A method according to claim 1 or 2, wherein each joint has an individual movement region, and wherein the difference in joint setting of any of the plurality of joints between adjacent boom joint configurations in the search set is less than a predetermined difference in joint setting.

4. A method according to claim 3, each joint comprising an individual movement region representing the positions to which the joint can be set, wherein the predetermined difference in joint setting is determined at least partly based on one or more from: the individual movement region of at least one of the plurality of joints, a maximum speed of at least one of the plurality of joints, a maximum acceleration of at least one of the plurality of joints.

5. A method according to any one of the claims 1 -4, further comprising, when a boom joint configuration is added to the search set: stochastically selecting the boom joint configuration to be added, and / or utilizing inverse kinematics algorithm to calculate a boom joint configuration for an intermediate pose between the first pose and the second pose, and determining whether the calculated boom joint configuration avoids obstacles indicated in the representation of the surroundings.

6. A method according to any one of the claims 1 -5, the computing further comprising: utilizing a Hybrid Forward Rapid exploring Random Tree (RRT) algorithm to: generate the search set in the form of a search tree of nodes through iteration, each node representing a boom joint configuration and corresponding pose, the iterations of the RRT algorithm comprises at least one of: stochastically selecting a boom joint configuration and determining acorresponding pose; utilizing an inverse kinematics algorithm to calculate a boom joint configuration for an intermediate pose between the first pose and the second pose; determining whether a selected and / or calculated boom joint configuration avoids obstacles indicated in the representation of the surroundings; and searching the search tree for a path from the first pose to the second pose avoiding obstacles.

7. A method according to claim 6, further comprising, when inverse kinematics have been utilized to calculate a boom joint configuration for at least one intermediate pose: searching the search tree of nodes for a path to the at least one intermediate pose, and when a path to the at least one intermediate pose is found, utilizing the intermediate pose as starting point for continued search in the search tree of nodes for the path between the first and second pose following further addition of boom joint configurations to the search tree.

8. A method according to claim 6 or 7, further comprising, when searching the search tree of nodes towards a particular pose: starting from a node reached during a previous search and that represents a nearest pose to the particular pose.

9. A method according to any one of the claims 6-8, further comprising: utilizing a first Hybrid Forward RRT algorithm for generating a first search tree of nodes through iteration from the first pose towards the second pose, utilizing a second Hybrid Forward RRT algorithm for generating a second search tree of nodes through iteration from the second pose towards the first pose, and searching both search trees for a path from the first pose to the second pose avoiding obstacles, and combining the paths when identifying a same boom joint configuration occurring in both search trees.

10. A method according to any one of the claims 1 -9, further comprising: generating the representation of the surroundings utilizing one or more from: a tunnel model and / or a rock face model being computed utilizing one or more of: a drill plan contour; a theoretical tunnel profile; a scanning of the surroundings, e.g., utilizing LIDAR; a plane with a safety distance from the theoretical rock face; geometries of the drill rig;11 . A method according to claim 10, wherein the geometries of the drill rig comprises one or more from: current configuration of one or more booms; other machine geometries, such as jacks, cabin and carrier.

12. A method according to any one of the claims, further comprising: restricting joint position settings of at least one of the plurality of joints to a portion of the individual movement region of the at least one joint when reaching the second pose.

13. A method according to claims 12, one of the plurality of joints controlling a feeder displacement, the constraints comprising to ensure a minimum remaining feeder displacement when reaching the second pose.

14. A method according to any one of the claims 1 -13, further comprising, prior to controlling the joints of the boom to carry out the movement from the first pose to the second pose: subjecting the computed path for manoeuvring the boom from the first pose to the second pose to a smoothening operation comprising at least one of: repeatedly searching a shorter path between boom joint configurations in the computed path, and replacing the path with the shorter path when possible; imposing limitations on maximum speed of motion, and / or acceleration,of one or more of the plurality of joints when manoeuvring the boom according to the path.

15. A method according to any one of the claims 1 -14, further comprising: determining the first pose and the second pose in relation to a reference point, the reference point being a point in a local coordinate system of the drill rig, and / or a reference point in a coordinate system of the surroundings of the drill rig.

16. A method according to any one of the claims 1 -15, wherein the boom carries a work equipment, the manoeuvring of the boom from the first pose to the second pose manoeuvring the work equipment from the first pose to the second pose.

17. A system for manoeuvring a boom of a drill rig (200) from a first pose to a second pose, the boom being attached to a carrier (201 ) and comprising a plurality of joints (231 -236), wherein the manoeuvring comprises to move the boom (203-205) from a first boom joint configuration of the first pose to a second boom joint configuration of the second pose by manoeuvring at least one of the plurality of joints, each boom joint configuration corresponding to a particular setting of the joints, the system comprising means for, prior to manoeuvring the boom from the first pose to the second pose: determining a representation of the surroundings of the boom in a 3D coordinate system, the representation of the surroundings indicating obstacles in the surroundings, computing a path for manoeuvring the boom from the first boom joint configuration to the second pose in the coordinate system, the path comprising boom joint configurations representing intermediate poses between the first pose and the second pose in the coordinate system, the path being computed to avoid obstacles, the computing comprising: generating a search set comprising a plurality of different boom joint configurations and corresponding poses, the search set indicating boom joint configurations avoiding indicated obstacles, the generated search set further comprising boom joint configurations calculated for intermediate poses between the first pose and the second pose using inverse kinematics, andsearching the search set for a subset of boom joint configurations forming a path avoiding obstacles from the first pose to the second pose, the method further comprising: controlling the joints of the boom to carry out the movement from the first pose to the second pose using the identified subset of boom joint configurations.

18. A drill rig comprising a system according to claim 17.

19. A 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 to 16.

20. A computer-readable medium comprising instructions which, when executed by a computer, cause the computer to carry out the method according to any one of the claims 1 to 16.

Images