Field of the invention

[0001] The invention relates to the definition of data for automatic control of mobile mining machines and especially to modelling a production area and teaching the route of the mining machine for the purpose of arranging automatic control for the mining machine.

Background of the invention

[0002] Various mobile mining machines, such as rock drilling equipment, loading equipment and transport equipment, are used in a mine. Mining machines may be manned or unmanned. Unmanned mining machines may be remote-controlled from a control room, for instance, and they may be equipped with measuring instruments suitable for location determination. Unmanned mining devices may be controlled along a required route in the mine, as long as the location of the device can be determined. The location of the device may be determined by using laser scanners, for instance.

[0003] Publication WO 2007/012198 discloses a method for automatically guiding a mining vehicle. By driving the mining vehicle manually or by using a teleoperator, an operator teaches to the mining vehicle a route, along which the mining device may move without intervention from the operator.

[0004] A pre-taught reference model on the tunnels of the production area is required for use as a base to teach the route. This reference model may be called an environment model. The environment model is typically taught by driving the mining machine through the necessary tunnels in the production area. Before the environment model can be used to define the route, it needs to be bound to the coordinate system of the production area. When the environment model of the production area has been taught, bound to the coordinate system and stored in the information system, the mining machine is taught a route required for a specific production task by driving it along the route. A navigation system determines the location of the mining machine, and the locations of route points of a driven route may be defined relative to the environment model. Brief description of the invention

[0005] An improved solution for modelling a production area and for defining routes has now been developed for automatic control of moving mining devices. The solution is characterised by what is stated in the independent claims. Preferred embodiments of the invention are set forth in the dependent claims.

[0006] According to an aspect of the invention, an environment model and route are defined on the basis of location data obtained from a run of the mining machine between a first area and a second area in a computer- aided manner by performing the following steps in a data processing device adapted to generate an environment model and route: defining an initialisation point in the first area for the definition of the environment model, defining data for the environment model on the basis of first location data, when driving the mining machine from the first area to the second area, the first location data being relative to said initialisation point; defining data for route points of the route by using at least some of the environment model data and second location data obtained when driving the mining machine between the second and first areas, the second location data being relative to said initialisation point; and storing the data defining the route for use in the automatic control of the mining machine.

[0007] The present invention provides several advantages which will become apparent from the detailed description. Because the location data of the route points of the route may be defined relative to the initialization point of the environment model, a separate binding to the coordinate system or map of the production area done by a user is not needed before the environment model is used in generating routes. This way, it is possible to shorten the time required to teach the production area and routes, during which time the production area must be sealed off. This enables both the modelling of a production area section and the definition of the route through this section by driving the mining machine once back and forth.

Brief description of figures

[0008] Some embodiments of the invention will now be described in greater detail by means of some preferred embodiments and with reference to the attached drawings, in which Figure 1 is a schematic side representation of a moving mining device,

Figure 2 shows from the top an arrangement for positioning and controlling a mining machine according to an embodiment,

Figure 3 shows an apparatus according to an embodiment for defining routes of a mining machine,

Figure 4 shows a method according to an embodiment, and

Figure 5 illustrates a route defined in a production area.

Detailed description of an embodiment of the invention

[0009] Figure 1 shows a mobile mining machine 1 , in this case a loading device with a bucket 15 in front for transporting and loading excavated material. The mining machine 1 may alternatively be a rock drilling device or a transport device with a box, for example. The mining machine 1 comprises a movable carrier 2 with several wheels 3, of which at least one is a drive wheel that is driven by a motor 4 through transmission. The motor 4 may be an electric motor, combustion engine, hydraulic motor or any other device for providing a rotation torque. Transmission usually comprises a gearbox 5 and required cardan shafts 6, differential gear and other power transmission members for transmitting the rotation torque from the motor 4 to the drive wheels. The mining machine 1 is also equipped with a control system that comprises at least a first control unit 7 that is arranged to control actuators in the mining device 1 for the purpose of controlling and driving the machine.

[0010] Further, the mining machine 1 may have a data transfer unit 8, with which the first control unit 7 may establish a data transfer connection to a second control unit 10 external to the mining machine 1 by utilising a wireless connection provided by a base station 9. The second control unit 10 may reside in a control room 11 that may be arranged outside the mine. The control units 7 and 10 may be computers equipped with appropriate software.

[0011] It should be noted that a mining machine may generally refer to different machines used in rock excavation operations in a surface or underground production area and which may also be used at other locations than in the actual mines. Figure 1 is a simplified figure, and the control system of a mining machine 1 typically comprises several units for implementing different control functions. The control system of the mining machine 1 may be a distributed entity formed of modules connected to a CAN (Controller Area Network) bus, for example, which manages all measurements and controls of the machine. The information system of the control room 11 may also comprise one or more servers, databases, operator workstations and a connection to other networks and systems.

[0012] The control system 1 of the mining machine comprises a positioning system or unit. According to an embodiment, the positioning system comprises at least one gyroscope 12 that may be used to accurately determine the direction of the machine for positioning. The positioning system further comprises means for determining the distance the machine 1 has travelled. One or more sensors 13 may be used to measure the rotation of the wheel 3. On the basis of the measuring data, the positioning system determines the rotation movement of the wheel and then calculates the distance the machine has travelled. The positioning system may further comprise one or more scanners 14, such as a laser scanner or a corresponding device capable of scanning the space and shapes surrounding the mining machine 1.

[0013] Figure 2 shows in accordance with an embodiment the principle of the definition and use of a route used in positioning and based on scanning. On one or both sides of the mining machine 1 , there may be laser scanners 14, with which the profile and surface contours of a mining tunnel 20 may be determined.

[0014] The route 21 of the mining machine 1 may be established by teaching. The mining machine 1 is then driven by manual control along the required route and route points 22a, 22b, 22c of the route 21 obtained on the basis of location data derived from processing scanning data are stored into a memory at regular intervals. When the required route 21 has been taught and stored into the memory of the control system, the mining machine 1 may be controlled to drive the route 21 autonomously. A production run of a mining machine may be done unmanned with the control system taking care of the control. The location of the mobile mining machine 1 may be determined during automatic control by using laser scanners 14, for instance. Laser scanners scan the wall profiles of the tunnel to determine location on the basis of a pre- stored environment model, and no separate identifiers, such as reflectors or radio frequency identifiers, are needed on the tunnel walls. The control system controls the driving of the mining machine on the basis of the determined location and the route point data of the route in such a manner that the mining machine remains on the route 21. [0015] A solution has now been developed that enables the use of the environment model for teaching routes immediately after teaching the environment model on the basis of driving the mining machine 1. This makes it possible to teach the environment model and route substantially in run-time by one back and forth drive between a first area and a second area. The environment model generally refers to a model that depicts a production area and has been defined, for instance, by driving a mining device in the production area and by scanning wall profiles. The production area generally refers to an area where a mobile mining machine is used. The environment model comprises at least location data on the tunnel walls, but may also comprise other data, such as tunnel wall profile data. The route data generally refers to data, on the basis of which the mining machine 1 may be controlled to drive a required route.

[0016] Figure 3 shows an apparatus according to an embodiment for defining models for facilitating automatic guiding of a mining machine. The apparatus comprises at least a unit 30 for defining routes and especially for teaching an environment model and route substantially in run-time on the basis of a drive between a first area and a second area relative to the initialisation point of the definition of the environment model. Alternatively, the apparatus may comprise a first physical or functional unit or an application for defining an environment model and a second unit or application for defining a route. However, in the following and in Figure 3, an embodiment is disclosed, in which one unit, which is called a route definition unit or application, takes care of the definition of both the environment model and route.

[0017] The unit 30 may for instance be implemented by a processor of a general-purpose data processing device, in which one or more computer programs executing route definition functions are run. The computer program comprises a code for implementing at least some of the features related to the definition of the environment model and route illustrated in Figure 4. The computer program may be stored on a machine-readable storage medium, such as a memory 31 or a separate memory means, from which the computer program may be fetched for execution on the processor.

[0018] The route definition unit 30 is connected to the memory 31 , in which information required or defined by the unit 30, such as the environment model, route, property data of the mining machine, and other data and settings affecting route definition, may be stored. The route definition unit com- prises an interface for a display 32 and at least one interface for at least one input device 33, such as keyboard and/or mouse. The apparatus may also have one or more other interfaces to other systems. The apparatus typically comprises at least one data transfer unit that may utilise standard TCP/IP- based (Transport Control Protocol / Internet Protocol) network protocols, for instance.

[0019] The route definition unit 30 is operationally connectable to a positioning system 34 that defines the location of the mining machine 1 during its run. The positioning system 34 may be part of a navigation system implemented by the mobile mining machine 1 , such as the control unit 7, and possibly partly also by the external control unit 10 of the mining machine 1.

[0020] The route definition unit 30 may be implemented on an operator workstation, for instance. However, the route definition unit 30 need not be implemented in the data processing apparatus used in controlling mining operation or even connectable thereto, which means that defining routes is not fixed to location or specific apparatus. However, it should be noted that it is possible to implement at least some of the present technical features related to route definition, for instance the route definition unit 30, in the mobile mining machine 1 and its data processing apparatus.

[0021] At least the apparatus implementing the route definition unit 30 may be implemented in different appropriately configured data processing devices. A software application implementing the route definition unit 30 may be stored in a portable computer, for instance, from which route data may be transferred over a telecommunications connection or using a memory device to the control unit 10 of the control room, for instance.

[0022] The system may also have a specific drive task management system, for instance an application executed in the control unit 10 residing in the control room 11. The drive task management system defines drive tasks on the basis of input from the operator and transmits drive task data to the control unit 7 of the mining machine 1. The drive task management system may be connected to the memory 31 and it may fetch pre-stored route data from the memory and forward route data and/or control commands to the control unit 7 or navigation system of the mobile mining machine 1.

[0023] Figure 4 shows a method according to an embodiment, which may be performed in the route definition unit 30 illustrated in Figure 3, for instance. [0024] When there is a need to define an environment model and route for a new section of a production area, the system may move to step 40. Defining or recording an environment model is started and initialised by defining an initialisation point for the definition of the environment model in a start area. This initialisation point is used as a reference point in defining the environment model and route. The mining machine 1 is driven from the start area toward the end area of the teaching of the environment area.

[0025] In step 41 , the location data of the walls in relation to the reference point, that is, initialisation point, are defined on the basis of the measurements and distances obtained during run-time scanning of the mining machine 1. In step 41 , it is thus possible to define wall location points as differences to the initialisation point. Alternatively, if a separate application or unit is used that performs the calculations of the wall location data, the wall location data relative to the initialisation point are received in step 41.

[0026] If the environment model is defined on the basis of scanning, the location data comprises wall location data defined on the basis of tunnel wall scanning and distance measurement. The measuring data received from the scanners of the mining machine 1 is filtered and processed and wall location data is defined on the basis of distance measurement during the driving of the mining machine. In this embodiment, the location data defines the location of the wall at the height of the scanner 14 in the mining machine 1.

[0027] The application defining the environment model also receives possible user input. If in step 42, an input to stop the teaching of the environment model is detected, that is, when the desired end area of the environment model teaching is reached, the definition of the environment model is ended. The final environment model is stored 43 into the memory 31 , for instance. Alternatively, the definition 41 of the environment model is continued. It should be noted that environment model data may be stored immediately upon definition.

[0028] The present embodiment makes it possible to save time used in teaching routes, because route definition may be begun immediately after the teaching of the environment model is ended. Preferably the entire environment model between the start area and end area is defined in run-time when driving the mining machine between the start area and end area.

[0029] Next, the application proceeds to step 44, in which the definition of a route is begun in the area of the defined environment model. Accord- ing to one embodiment, the environment model and route are taught during one back and forth drive, and the definition of the route is essentially started from the area where the definition of the environment model ended, that is, the end area comprising the end point of the teaching drive of the environment model.

[0030] First, the start point of the route relative to the initialisation point of the environment model definition defined in step 40 is initialised 45. This means that the current location of the mining machine 1 in relation to the initialisation point is defined on the basis of the already stored environment model data. The start point may be defined on the basis of input received from the user, such as operator or designer, or automatically. It should be noted that the initialisation of the location is required at least if the mining machine 1 is been moved after ending the teaching of the environment model before starting the teaching of the route. If the machine is not moved after ending the teaching of the environment model and the route starts directly from the end point of the teaching of the environment model, a separate initialisation is not necessarily needed, and it is possible to start directly defining route points of the route relative to said initialisation point. The start point of the route is defined relative to the environment model defined in steps 41 to 43.

[0031] In step 46, data of the route points of the route are defined using at least some of said environment model data, that is, the location data of the points defining the environment model defined in step 41 , and second location data obtained when driving the mining machine at least partly between the second area and the first area. According to a preferred embodiment, the route is defined immediately after defining the environment model, when the mining machine 1 returns from the second area back to the first area or at least towards the first area. The route point data of the route are defined using as the reference point the initialisation point of the definition of the environment model. This may be done by defining the location data of the route points directly or indirectly relative to the initialisation point of the definition of the environment model. If the location data of the route points are defined as differences to the start point of the route initialised in step 45, the route points are defined indirectly on the basis of the initialisation point of the definition of the environment model, because the start point of the route is defined relative to the initialisation point of the definition of the environment model. [0032] Depending on the implementation, the application or unit (30) implementing the method of Figure 4 can either receive location data calculated on the basis of the information received from the mining machine 1 by another unit or define the data by itself. Route points may be defined at predefined intervals, for instance. However, it should be noted that when approaching a bucket unloading point, route points may need to be defined at shorter intervals than during the rest of the drive. At least the location of the route point is defined for each route point, but typically also other route point-specific information, especially the driving speed.

[0033] The need to end the definition of the route may be detected in step 47 for instance in response to an input received from the user to stop the teaching of the route. When this type of input, for instance, has been received, the current location of the mining machine 1 may be defined as the end point of the route. The route may define a route from the second area to the first area. Alternatively, the route is defined only partly on the basis of a run of the mining machine 1 which is reverse to the teaching of the environment model. Thus, the route may begin in step 45 in the same area as where the definition of the environment model ended, but end at a different point than where the teaching of the environment model started. It should be noted that teaching the route is not limited to driving in the opposite direction to the teaching run of the environment model, and the route may also be taught by driving the mining machine 1 in the same direction as when teaching the environment model, on the basis of environment model wall location data bound to the initialisation point.

[0034] The data defining the route are stored 48 in the memory 31 , for instance, for use in automatically guiding the mining machine. The data of the route and environment model may be bound to the coordinate system of the production area, but this is not necessary. According to an embodiment, the route is stored in a structured XML (extensible markup language) file. However, it should be noted that applying the present embodiments is not limited to a specific storage format.

[0035] It should be noted that the terms "start point" and "end point" should be understood widely to refer to the start and end points of the environment model or route teaching, and the task of a mining machine using the defined route need not start at the start point. Thus, the first taught route may in reality be a route, along which the mining machine returns to its waiting location or bucket unloading location, for instance.

[0036] Figure 4 described above illustrates in a simplified form only one embodiment and the invention may be implemented in many different ways. For instance, step 46 may comprise several sub-steps for defining the route point data. The environment model and/or route defined using the method of Figure 4 may appropriately be edited and supplemented, for instance according to input received from the user of the route definition unit through the input device 33. Some other supplementary or alternative embodiments are described in the following.

[0037] Figure 5 also shows a simplified model 50 describing a section of a production area, such as a two-dimensionally presented environment model that shows at least wall 51 locations illustrated with a dotted line. The model has been defined on the basis of steps 40 to 43 when driving the mining machine 1 from point 53 (initialisation point) to point 54. Figure 5 also shows route points 52 of the route. When the environment model 50 has been taught, it is possible to continue in the manner shown in steps 44 to 48 to teach the route points of the route starting from point 54, for instance, and possibly proceeding to point 53.

[0038] According to an embodiment, the environment model defines the x and y coordinates of the points depicting the locations of the walls directly or indirectly in relation to the initialisation point of the definition of the environment model. A two-dimensional tunnel map may be produced by outputting the points of the environment model on the xy plane. If three-dimensional scanning was used, z coordinates could also be recorded, whereby a 3D profile of the tunnel could be stored.

[0039] The route data comprise at least the location data of each route point of the route, but they may also contain other route point- and route point group-specific control data, such as information on speed, gear, steering angle, position of a possible boom or lifting arm of the mining machine, and position of a possible bucket.

[0040] According to an embodiment, in step 46 a speed reference and gear data are calculated automatically for each route point for the purpose of forming a speed profile to be used on the route defined by the route points. The width of the tunnel and the winding of the route are among other things taken into consideration in calculating the profile. The gear reference value may be automatically specified to provide sufficient motor revolutions with the gear in question. This ensures that the hydraulic steering of the machine receives enough oil to enable a sufficiently fast turning. The calculation of the speed profile also makes sure that the speed decreases in a suitably anticipatory manner before curves or narrow sections.

[0041] An environment model and/or route defined in the above manner may also be utilised in defining other routes. Typically, it is also necessary to define a reverse return route so that a two-directional drive task can be performed. Then, if the route defined in steps 44 to 48 is unidirectional, a new return route may be added to the system or the route definition continued in the return direction. It should be noted that it is also possible to add new routes, in the definition of which the information of the environment model and/or route defined according to the method described in connection of Figure 4 is only partially used. For example, it is possible to define only a partial return route, in which the route points of the two first segments are defined in reverse on the basis of the last route points of the route, but the partial return route then branches into a different tunnel in the third segment.

[0042] By using at least partly the environment model defined in connection with Figure 4, it is possible to define additional routes on the basis of the driving of the mining machine 1. Alternatively, according to an embodiment, a return route that is at least partly reverse to the route is defined automatically without needing to drive the mining machine back from the end point of the route.

[0043] According to an embodiment, the route defined in steps 44 to 48 defines a route from a loading site to an unloading site, that is, the environment model is first taught by driving the mining machine 1 from the unloading site to the loading site. The mining machine 1 can then also be taught a return route from the unloading site to the loading site by using at least part of the data in the environment model as well as second location data obtained when driving the mining machine again from the unloading site to the loading site. Alternatively, the return route from the unloading site to the loading site is defined for the mining machine 1 by computer on the basis of said route data by defining as the route points of the return route the route points of the route in reverse order. The route points of the return route may also be directly or indirectly in relation to the initialisation point of the definition of the environment model. [0044] An at least partial return route may be defined on the basis of the data of the route without driving in the manner illustrated in the following. An individualized route identifier, with which the route points defined for the return route are associated, is defined for the return route. For defining the return route, the route points of the route are processed in reverse order. First, the start point of the return route and at least some of the route points are defined. If the return route begins at exactly the end point of the route, the end point of the route may directly be defined as the first route point, or start point, of the return route. However, on the basis of user input or a setting of the route definition application, the first route point may differ somewhat or substantially from the end point of the route. Location data is defined for each route point of the return route, and they may be directly copied from the location data of the route points of the route.

[0045] Route curvature is defined for the route defined by the route points on the basis of the location data of the defined return route points. On the basis of the route curvature, it is possible to define the driving speed for each route point. It should be noted that the route definition algorithm may also be arranged to perform other actions for defining the route, for example to define the steering angle for each route point. The route definition unit 30 may be arranged to calculate, how much space the mining machine needs around it at the steering angle position required at the route point, on the basis of the outer dimensions and/or kinematics data of the machine. When the space required by the mining machine is defined, the route definition unit may check for each route point, whether the machine is at a predefined minimum distance from the walls. If necessary, the location of the route point may be changed.

[0046] According to an embodiment, the routes are defined as interconnected route sections, or segments, that have their own identification codes. For each segment it is in turn possible to define (limit) values for driving speeds and other functions according to the properties of the segment. These definitions may even be provided for each mining machine taking into consideration the properties of the machine. The route definition unit 30 may be arranged to define in the manner described above segment-specific data, that is, in the simplest form, the data of the route points belonging to each segment and the identification code of the segment. Thus, the route definition described above may refer to the definition of a set of interconnected route segments. Segment-based route definition provides the advantage, for instance, that the data of the route points of the segment need not stored separately for each route running through this segment. The segment-specific data may be stored in the memory of the control equipment of the mining machine 1 , whereby the definition of the route may take place simply by sending a list of identification codes of the route segments associated with a task. Segment-based route definition is described in more detail in publication WO2004/085965, which is incorporated herein by reference.

[0047] Depending on the implementation, the route definition unit 30 may automatically take into consideration a location change required by a change of driving direction in step 45. The location definition for defining the environment model and route may be arranged such that an axle in front of the mining machine 1 always defines the location of the route points and an axle at the back only tags along. At a reversal point, the front axle changes, so the monitoring of the points to be taught transfers from one axle to the other and a gap the size of the axle spacing, which may be 3 to 4 metres, is created in the route. It is possible to edit points into this gap in such a manner that to the beginning of the segment starting from the reversal, points are added so that the start point is approximately the same as the last point of the ending segment.

[0048] According to one embodiment, the reversal may take place in one segment. In this embodiment, it is possible to automatically add route points, whereby the outward and return sections at the reversal point are automatically correct. For instance, if a return route is defined for a route, the route is automatically defined to end at the same point, from which the return route begins.

[0049] It should also be noted that the route definition unit 30 may be arranged to add route points in other situations, if necessary. In addition, route points may be added in a reversal situation regardless of whether a new segment starts at the reversal or whether the points around the reversal point belong to the same segment.

[0050] It is obvious to a person skilled in the art that as technology advances, the basic idea of the invention may be implemented in many different ways. The invention and its embodiments are thus not restricted to the examples described above, but may vary within the scope of the claims. Thus, different features may be left out, modified or replaced by equivalent features, and the features described in this patent application may be combined to form various combinations.