Rotary boring mining machine inertial steering system

Abstract

A mining system with an inertial guidance system configured to enable precise excavation of geological material without a need to advance a survey line over a long distance and/or nonlinear excavation path, thereby maximizing productivity of the mind by minimizing a width of un-mined material necessary for support between adjacent excavation paths and minimizing equipment downtime.

Claims

1. A mining system with advanced directional guidance configured to enable precise excavation of geological material without a need to advance a survey line over a long distance a nonlinear excavation path, the mining system comprising: a mining machine having a steerable drive mechanism configured to advance the mining machine along an intended, nonlinear excavation path, a cutting mechanism configured to separate geological material from a wall of the excavation path, an auger mechanism configured to collect the separated geological material, and a conveyor mechanism configured to convey the collected geological material to a rear of the mining machine; a conveyor chain comprising a plurality of conveyor sections configured to convey the geological material to a mine exit; a bridge coupling the conveyor chain to the mining machine, wherein the bridge is configured to provide degrees of freedom to enable portions of the conveyor chain to move side-to-side and be rotated left-or-right to align the conveyor chain substantially perpendicular to a face of excavation, and to align the conveyor mechanism and the conveyor chain; and an inertial guidance system operably coupled to the bridge, the inertial guidance system comprising at least one accelerometer configured to sense acceleration along an x-axis of the mining machine, along a y-axis of the mining machine, and along a z-axis of the mining machine; at least one gyroscope configured to sense rotation about the x-axis of the mining machine, rotation about the y-axis of the mining machine, and rotation about the z-axis of the mining machine; and a programmable logic controller configured to receive sensed acceleration data from the at least one accelerometer and rotation data from the at least one gyroscope, determine movement of the mining machine as a function of time, and compute directional guidance to maintain advancement of the mining machine along the intended, nonlinear excavation path.

2. The mining system of claim 1, wherein the inertial guidance system does not rely on laser-based sensors for computing the directional guidance.

3. The mining system of claim 1, wherein the inertial guidance system is configured to track changes in speed or direction of the mining machine and compute directional guidance based on the changes in speed or direction to maintain advancement of the mining machine along the intended, nonlinear excavation path.

4. The mining system of claim 1, wherein the intended, nonlinear excavation path is a non-planar excavation path.

5. The mining system of claim 1, wherein the inertial guidance system comprises at least three accelerometers, each of the three accelerometer configured to sense acceleration of the mining machined along the x-axis of the mining machine, the y-axis of the mining machine, and the z-axis of the mining machine respectively.

6. The mining system of claim 1, wherein the inertial guidance system comprises at least three gyroscopes, each of the three gyroscopes configured to sense rotation of the mining machined about the x-axis of the mining machine, the y-axis of the mining machine, and the z-axis of the mining machine respectively.

7. The mining system of claim 1, wherein the directional guidance is provided as visual or auditory information to an operator whom manipulates controls of the steerable drive mechanism to affect steering.

8. The mining system of claim 1, wherein the inertial guidance system further includes a memory in which the movement of the mining machine as a function of time is stored.

9. The mining system of claim 1, wherein the inertial guidance system further includes a display that displays information regarding the directional guidance.

10. The mining system of claim 9, wherein the display is configured to graphically display the movement of the mining machine as a function of time.

11. The mining system of claim 9, wherein the display is configured to graphically display a comparison of the intended, nonlinear excavation path to an actual excavation path of the mining machine.

12. The mining system of claim 1, wherein the inertial guidance system further includes a communication bus configured to transmit the computed directional guidance to the steerable drive mechanism.

13. The mining system of claim 1, wherein the conveyor chain further comprises a plurality of bridges that couple the one or more conveyor sections together.

14. The mining system of claim 13, wherein the at least one bridge of the plurality of bridges comprises a second inertial guidance system configured to determine movement of the at least one bridge as a function of time, and compute directional guidance to the at least one bridge to maintain the alignment of the conveyor chain.

15. An inertial guidance system for a mining machine, the internal guidance system operably coupled to a bridge connecting the mining machine and a conveyor chain, the system comprising: at least one accelerometer configured to sense acceleration along an x-axis of the mining machine, along a y-axis of the mining machine, and along a z-axis of the mining machine; at least one gyroscope configured to sense rotation about the x-axis of the mining machine, rotation about the y-axis of the mining machine, and rotation about the z-axis of the mining machine; a programmable logic controller configured to receive sensed acceleration data from the at least one accelerometer and rotation data from the at least one gyroscope, determine movement of the mining machine via movement of the bridge in three-dimensional space as a function of time, and compute directional guidance to maintain advancement of the mining machine along the intended, nonlinear excavation path; and a communication bus configured to transmit the computed directional guidance to a steerable drive mechanism of the mining machine.

16. The inertial guidance system of claim 15, wherein the inertial guidance system does not rely on laser based sensors for computing the directional guidance.

17. The inertial guidance system of claim 15, wherein the inertial guidance system is configured to track changes in speed or direction of the mining machine and compute directional guidance based on the changes in speed or direction to maintain advancement of the mining machine along an intended, nonlinear excavation path.

18. The inertial guidance system of claim 15, wherein the intended, nonlinear excavation path is a non-planar excavation path.

19. The inertial guidance system of claim 15, wherein the inertial guidance system comprises at least three accelerometers, each of the three accelerometer configured to sense acceleration of the mining machined along the x-axis of the mining machine, the y-axis of the mining machine, and the z-axis of the mining machine respectively.

20. The inertial guidance system of claim 15, wherein the inertial guidance system comprises at least three gyroscopes, each of the three gyroscopes configured to sense rotation of the mining machined about the x-axis of the mining machine, the y-axis of the mining machine, and the z-axis of the mining machine respectively.

21. The inertial guidance system of claim 15, wherein the inertial guidance system further includes a display that displays information regarding the directional guidance.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The disclosure can be more completely understood in consideration of the following detailed description of various embodiments of the disclosure, in connection with the accompanying drawings, in which:

(2) FIG. 1 is a map view depicting a potash mine.

(3) FIG. 2 is a cross-sectional view depicting several rooms of a mine under construction.

(4) FIG. 3A is a cross-sectional view depicting an undulating mineral deposit.

(5) FIG. 3B is a cross-sectional view depicting a mining system with advanced directional guidance, mining the vein shown in FIG. 3A, in accordance with an embodiment of the disclosure.

(6) FIG. 4A is a schematic view depicting a mining machine in accordance with an embodiment of the disclosure.

(7) FIG. 4B is a schematic view depicting an inertial guidance system of the mining machine of FIG. 4A.

(8) While embodiments of the disclosure are amenable to various modifications and alternative forms, specifics thereof shown by way of example in the drawings will be described in detail. It should be understood, however, that the intention is not to limit the disclosure to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the subject matter as defined by the claims.

DETAILED DESCRIPTION OF THE DRAWINGS

(9) According to embodiments, apparatus and methods for a mining system, such as room-and-pillar mining, are disclosed. The guidance system comprises an inertial system, rather than or in addition to conventional laser beam guidance. By using an inertial guidance system, downtime for mining equipment can be minimized, and the heading of the mining equipment can be controlled more accurately over both longer distances and non-linear excavation paths.

(10) Referring to FIG. 1, a map view of an example potash mine 10 is depicted. Specifically, FIG. 1 depicts a room-and-pillar structure type mine, including mineshafts 12a and 12b, connected to a network of rooms 14 or excavated paths (depicted as shaded regions) with pillars 116 or un-mined material necessary for support (depicted as un-shaded regions) positioned between adjacent rooms 14. Mineshafts 12a and 12b are often several hundred meters long, extending from the surface (not shown) to the subterranean geological material and/or mineral deposits below. In some cases, the mineshafts 12a and 12b extend substantially vertically, primarily perpendicular to the map view depicted in FIG. 1.

(11) Rooms 14 follow the vein of subterranean geological material. Potash mines, in particular, can be quite extensive in size; for example, a typical potash mine can extend over several hundred square kilometers. As the mine 10 is constructed, and the network of rooms 14 are excavated and geological material transported to the surface, pillars 16 of un-excavated material are left in place to provide structural support to maintain the integrity of the rooms 14. Accordingly, during mining operations, care must be taken to ensure that the pillars 16 have a size sufficient to provide the needed structural support. Pillars 16 of insufficient size may lead to a collapse, or partial collapse, of one or more of the adjacent rooms 14.

(12) Referring to FIG. 2, a cross-sectional view of a mine 110 under construction is depicted. Mine 110 includes three completed rooms 114a, 114b, and 114c, as well as a fourth room 114d under construction. Mine 110 further includes pillars 116. One end of the fourth room 114d defines a face 118, which is the portion of the unfinished room 114d from which geological material is being excavated or separated from the earth. As depicted, a mining machine 120 is arranged adjacent to the face 118 to affect the excavation. A conveyor chain 122 including a plurality of bridges 124 is positioned at the rear of the mining machine 120, opposite from the face 118, in order to transport the geological material to a mine exit.

(13) As depicted in FIG. 2, adjacent rooms 114a-114d are separated from one another by pillars 116. As previously described, the pillars 116 provide structural support for mine 110, thereby enabling the excavation of geological materials to safely take place in rooms 114a-114d. To maximize productivity of the mine by excavating as much geological material as possible, while ensuring adequate structural support, it is generally desirable that the rooms 114a-114d extend as close to parallel to one another as is structurally possible. Accordingly, the face 118 is generally substantially perpendicular to the direction in which the rooms 114a-114d extend.

(14) Referring to FIGS. 3A-B, a cross-sectional view of the earth depicting an undulating subterranean mineral deposit is depicted. In such a deposit, a vein of geological material 232 is positioned beneath a layer of non-mineral earth 228, which can vary in depth D from the earth's surface 230. Accordingly, efficient mining of such a deposit may require a nonlinear excavation path, or a network of rooms that vary in elevation so as to be centered on the vein of geological materials 232.

(15) As depicted in FIG. 3B, a mining machine 220 in accordance with an embodiment of the disclosure can be configured to follow the non-planar vein of geological material 232. Accordingly, the mining machine 220 can be advanced along the vein to separate the geological material 232 from the face 218 of the room 214 being excavated. The separated geological material 232 can then be collected and conveyed to a rear of the mining machine 120. At the rear of the mining machine 120, a conveyor chain 222, which may include a plurality of bridges 224, can cooperate to move or convey the geological material 232 towards a mine exit, such as a mine shaft. Thereafter, the geological material 232 can be transported to the earth's surface 230 for further processing and transport. Accordingly, an advantage of incorporating an inertial guidance system of the present disclosure, as opposed to conventional laser-based systems of the prior art, is the ability to track changes in speed and or direction of the mining machine 120 where excavation does not take place along a straight line or linear path, thereby reducing the downtime associated with advancing a laser-based survey line.

(16) Referring to FIGS. 4A-B, a mining machine 320 is depicted in accordance with an embodiment of the disclosure. In one non-limiting example, the mining machine 320 can be used in underground potash mining to extract concentrated KCl containing ore in a sedimentary formation. The mining machine 320 can be, for example, any of a variety of prime movers with a cutting or mining mechanism, such as, for example, a rotary boring mining machine, roadheader, continuous or drum miner, or the like. The height of the mining machine 320 can be complementary to the thickness of the seam or vein of geological material to be extracted. For example, the mining machine 320 can be of a height of 8 feet 2 inches, 8 feet 6 inches, or 9 feet. Other heights of mining machine 320 are also contemplated.

(17) In one embodiment, the mining machine 320 can include a steerable drive mechanism 334 as a prime mover. For example, in one embodiment, the steerable drive mechanism 334 can include wheels and/or tracks configured to advance the mining machine 320 along an intended excavation path.

(18) The mining machine 320 can further include a cutting mechanism 336. The cutting mechanism 336 can be configured to separate geological material from a wall or face of an excavation path. In some embodiments, the cutting mechanism 336 can be configured to move relative to a body of the mining machine through range of motion both laterally side to side and vertically up and down to effect separation of geological material from a wall of the excavation path. In some embodiments, the mining machine 320 can include either two or four rotary boring cutter heads, commonly referred to as two-rotor and four-rotor mining machines. A cutting mechanism 336 including alternative quantities of cutter heads or alternative cutting mechanisms is also contemplated.

(19) The mining machine 320 further includes an auger mechanism 338 configured to collect the separated geological material for deposit on a conveyor mechanism 340. The conveyor mechanism 340 is configured to convey the collective geological material to a rear 321 of the mining machine 320.

(20) A conveyor chain 322 can be operably coupled to the rear 321 of the mining machine 320. The conveyor chain 322 can be configured to convey the geological material to a mine exit, where it can be hoisted to the surface for further processing and/or transport. The conveyor chain 322 can include one or more conveyor sections 342 operably coupled to one another by one or more bridges 344, configured to provide four degrees of freedom to enable the conveyor chain 322 to be moved side-to-side (yaw) and/or rotated left-or-right (roll) in order to ensure it remains centered and aligned substantially perpendicular to the face.

(21) Referring to FIG. 4B, the mining machine 320 can further include an inertial guidance system 346. The inertial guidance system 346 can be configured to sense movement of the mining machine 320 and provide directional guidance as an aid in guiding the steerable drive mechanism 334 along the intended excavation path. In some embodiments, the directional guidance is provided visually or audibly to an operator, whom manipulates controls to affect steering. In other embodiments, the directional guidance is provided as data to a steerable drive controller 360 (as depicted in FIG. 4B) configured to autonomously control and/or assist an operator in steering the mining machine 320.

(22) The inertial guidance system 346 can include one or more accelerometers 348 and one or more gyroscopes 350. As depicted in FIG. 4B, the inertial guidance system 346 includes three accelerometers 348a-c configured to sense acceleration along respective x-, y- and z-axes of the mining machine 320. The inertial guidance system 346 additionally includes three gyroscopes 350a-c configured to sense rotation respectively about x-, y- and z-axes of the mining machine 320. A programmable logic controller 352 can be operably coupled to the at least one accelerometer 348 and gyroscopes 350, so as to receive the sensed acceleration and rotational data. The received data can be utilized to determine the movement of the mining machine 320 as a function of time. Thereafter, directional guidance to maintain advancement of the mining machine 320 along an intended excavation path can be computed.

(23) In some embodiments, the inertial guidance system 346 can further include a communication bus 354 configured to communicate at least one of the sensed acceleration and rotational data, the determine movement of the mining machine 320 is a function of time, and/or the computed directional guidance to maintain advancement of the mining machine 320 along an intended excavation path to an external receiver communicatively coupled to, for example, a server utilized in the planning and execution of mining operations. Various graphic displays can be computed from the communicated information, for example movement of the mining machine as a function of time, a comparison of the intended excavation path to an actual excavation path, previous excavation paths excavated by the mining machine 320, as well as un-mined material necessary for support in a map format, and computed directional guidance of the mining machine 320. In one embodiment, the inertial guidance system 346 includes its own display 356 for display of one or more graphic displays. The inertial guidance system 346 can further be configured with a memory 358 to permanently or temporarily store such information for later recall.

(24) In one embodiment, the one or more bridges 344 of the conveyor chain 322 can additionally include an inertial guidance system similar to the inertial guidance system 346 as described above. In particular, in certain embodiments, the one or more bridges 344 can be configured to sense acceleration and rotation about respective x-, y- and z-axes of the bridge 344, thereby providing information regarding operability of the conveyor chain 322 to an operator. For example, in one embodiment, the inertial guidance system of a bridge 344 can include at least three accelerometers, at least three gyroscopes, a programmable logic controller, and a communication bus. In some embodiments, an inertial guidance system can be included in each bridge of the conveyor chain 322. In other embodiments, an inertial guidance system can be included in certain selected bridges 344 of the conveyor chain, thereby providing an estimated position of the entire conveyor chain 322.

(25) With reference to FIGS. 2 and 4A-4B, in operation, a mine 110 is constructed by extracting material from rooms 114a-114d while leaving pillars 116 in place between and around the rooms 114a-114d to provide structural support. Accordingly, mining machine 320 is advanced along an intended excavation path while cutting geological material (e.g., ore), by forcing a cutting mechanism 336 into the mining face 118. The liberated ore can then be augured into the center of the mining machine 320, for example, by counter rotating rotors of an auger mechanism 338, and conveyed through the middle of the mining machine 320 by the conveyor section 342. The use of a conveyor chain 322 typically results in long rooms 114a-114d having narrow un-mined support pillars 116 positioned therebetween. The length of rooms can be, for example, between about 2500 feet and about 9000 feet, depending on the mining equipment and layout. Such a layout requires that the mining machine 320 closely follow a prescribed heading to prevent encroachment on the narrow pillar 116 that provides structural support for rooms 114a-114d.

(26) The ore can then be conveyed along a series of conveyor sections 342, which can be linked with one another and with the mining machine 320 by bridges 344, which is operated behind the mining machine 320. The conveyor chain 322 then conveys the ore to a shaft (e.g., shaft 12A or 12B of FIG. 1), where it is hoisted to the earth's surface for further transport and/or processing.

(27) In contrast to the conventional systems using laser sensing technology, as described in the Background section, mining machine 320, conveyor sections 342, and/or bridges 344 of the present disclosure can be aligned with one another using an inertial guidance system 346 including a combination of motion and rotation sensors (e.g. accelerometers 348 and gyroscopes 350). As the mining machine 320 advances towards the face 118, identifying location data can be measured by the inertial guidance system 346. For example, the mining machine 320 can determine acceleration and/or rotation along various directions, such as pitch, yaw, roll, forward or backward acceleration (wherein “forward” is towards the face 118), upward or downward acceleration (wherein “downward” is along the gravitational potential), or left to right acceleration (wherein left and right are the two directions orthogonal to both forward and downward directions). This acceleration and/or rotation data can be used to ascertain movement of the mining machine 320 and/or conveyor chain 322 as a function of time. By integrating the acceleration and/or rotation data twice, a position of the mining machine 320 and/or conveyor chain 322 in Euclidean space can be determined.

(28) In some embodiments, the inertial guidance system 346 can record location history so that conveyor chain 322 can be positioned behind mining machine 320 and reduce the quantity of spillage that could otherwise result from misaligned systems. That is, no laser sight is necessary for bridge 344 alignment use as in systems of the prior art. Additional sensing devices can be used to calculate the position and rotation of the bridges 344 and/or conveyor chain 322 relative to the mining machine 320. The inertial guidance system 346 can be in communication with the bridges 344 to receive and transmit positional data. The system can further be configured to provide a graphic display to the operator for manual use or to automatically control the mining equipment 120. Information generated by the inertial guidance system 346 can be stored in a memory 358 for later recall.

(29) In such systems, utilizing inertial guidance systems 346 (with or without laser guidance systems), the mining machine 320 and conveyor chain 322 need not be arranged along a straight line or linear path. Rather, the mining machine 320 can be driven along a vein of potash or other material that results in capturing the most geological material and in a manner that maintains an appropriate room-and-pillar arrangement (i.e., provides adequate support), whether or not the path taken by the mining equipment 320 is along a plane or constant elevation. In contrast to laser sight systems, this allows mining equipment to follow undulations in a vein without stopping to recalibrate.

(30) In embodiments where the position of mining machine 320 is stored, trailing conveyors sections 342 and bridges 344 can be routed along the same path that was taken by the mining machine 320, or another path that prevents spillage of the ore. Accordingly, survey control is only needed at the start of the room and therefore production delays during each shift can be reduced or eliminated. In some embodiments, the mining machine 320 can be automatically controlled to steer and/or correct heading over extended distances. For example, the mining machine 320 can be operated without an operator in the control canopy, potentially reducing the labor required to operate the mining machine 320.

(31) In embodiments, the rooms 114a-114d need not be exactly parallel to one another. For example, as previously depicted in FIG. 1, the rooms 14 can be arranged parallel one another, perpendicular to one another, or in any other orientation that provides sufficient support to the back of the mine and permitting extraction of materials such as potash from the mine. In any event, the incorporation of an inertial guidance system 346 into mining operations is advantageous in that it enables the determining the precise location of mining machine 320 and/or conveyor chain 322, whether or not those elements are arranged along a straight line as is required in conventional laser-sighting systems. Furthermore, inertial guidance systems (especially those that do not travel along a straight path) can allow the mining machine 320 to operate for long periods of time and/or long distances without stopping to recalibrate position, unlike laser-sighting systems which must be stopped to advance the laser every so often.

(32) Various embodiments of systems, devices, and methods have been described herein. These embodiments are given only by way of example and are not intended to limit the scope of the claimed inventions. It should be appreciated, moreover, that the various features of the embodiments that have been described may be combined in various ways to produce numerous additional embodiments. Moreover, while various materials, dimensions, shapes, configurations and locations, etc. have been described for use with disclosed embodiments, others besides those disclosed may be utilized without exceeding the scope of the claimed inventions.

(33) Persons of ordinary skill in the relevant arts will recognize that embodiments may comprise fewer features than illustrated in any individual embodiment described above. The embodiments described herein are not meant to be an exhaustive presentation of the ways in which the various features may be combined. Accordingly, the embodiments are not mutually exclusive combinations of features; rather, embodiments can comprise a combination of different individual features selected from different individual embodiments, as understood by persons of ordinary skill in the art. Moreover, elements described with respect to one embodiment can be implemented in other embodiments even when not described in such embodiments unless otherwise noted. Although a dependent claim may refer in the claims to a specific combination with one or more other claims, other embodiments can also include a combination of the dependent claim with the subject matter of each other dependent claim or a combination of one or more features with other dependent or independent claims. Such combinations are proposed herein unless it is stated that a specific combination is not intended. Furthermore, it is intended also to include features of a claim in any other independent claim even if this claim is not directly made dependent to the independent claim.

(34) Although a dependent claim may refer in the claims to a specific combination with one or more other claims, other embodiments can also include a combination of the dependent claim with the subject matter of each other dependent claim or a combination of one or more features with other dependent or independent claims. Such combinations are proposed herein unless it is stated that a specific combination is not intended.

(35) For purposes of interpreting the claims, it is expressly intended that the provisions of Section 112, sixth paragraph of 35 U.S.C. are not to be invoked unless the specific terms “means for” or “step for” are recited in a claim.