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EP-4457428-B1 - LONGWALL SHEARER POSITIONING METHOD, PAN FOR PANLINE, LONGWALL SHEARER SYSTEM

EP4457428B1EP 4457428 B1EP4457428 B1EP 4457428B1EP-4457428-B1

Inventors

  • TEINER, MARTIN
  • BILSING, Rene

Dates

Publication Date
20260506
Application Date
20221208

Claims (12)

  1. A computer-implemented method for determining a 3D position of a longwall shearer (100) traveling on a panline (200) along a longwall face (2) of an underground coal mining panel (4), the method comprising the steps of - retrieving (S10) sensor data indicative of an absolute shearer coordinate (x) and a shearer orientation (ψ, Θ, Φ) using a sensor device (220); - retrieving (S20) additional sensor data indicative of a relative shearer coordinate ( y ) using a sensor device (220); and - calculating (S30) and rendering, using a computer, the 3D position and orientation of the longwall shearer (100) based on the absolute coordinate (x), the shearer orientation (ψ, Θ, Φ), and the relative shearer coordinate ( y ), wherein the calculation comprises outputting the 3D position and orientation of the longwall shearer with a panline, characterized in that the absolute shearer coordinate (x) comprises multiple encoder positions (k-1, k, k+1), and wherein the additional sensor data indicative of a relative coordinate ( y ) comprises a retreat cylinder deflection ( y i ) in a face advance direction (y).
  2. The method according to claim 1, wherein the calculation step (S30) comprises, for a given encoder position (k), the steps of - retrieving (S310) a previous height value (z-1) of a previous floor profile (n-1), - predicting (S320) a current predicted height value (z P ) of a current floor profile (n), - observing (S330) a current observed height value (z O ) based on the retrieved height value, the retreat cylinder deflection ( y i ) and a current shearer roll angle (Φ n ), and - estimating (S340) a current estimated height value (z E ) of the current floor profile (n) by a combination of the current predicted height value (zP) and the current observed height value (zO).
  3. The method according to any of the previous claims 1 or 2, further comprising the steps of - determining (S350) current shearer shoe positions (S L , S R ) for a current encoder position (k) based on current retreat cylinder deflections ( y i ); and - determining (S360) a current shearer yaw angle (ψ) and the current shearer position in the moving direction (x).
  4. The method according to any of the previous claims, wherein the calculation step (S30) comprises an optimization algorithm, comprising a regression algorithm and/or a Kalman Filter.
  5. The method according to any of the previous claims, further comprising the step of interpolating (S360) relative coordinates ( y ).
  6. The method according to any of the previous claims, further comprising the step of generating (S400) a shearer trajectory from at least two different outputs of the calculation step.
  7. The method according to any of the previous claims, further comprising the steps of - predicting (S40) a predicted panline; - estimating (S50) an estimated panline; - calculating (S60) an expected panline based on the predicted panline and the estimated panline.
  8. The method according to claim 7, wherein the panline prediction () comprises the steps of - retrieving (S42) a current panline, - retrieving (S44) retreat cylinder deflections ( y i ) from the additional sensor data, and - retrieving (S46) a floor profile (300), wherein the panline prediction further comprises the step of - using physical equations suitable to calculate the position and orientation of each pan and/or the complete panline, wherein the physical equations comprise gravity, relay bar forces, and/or pan collision forces.
  9. The method according to claim 8, wherein the physical equations may be resolved by an optimization algorithm, preferably comprising a Newton method.
  10. The method according to claims 7-9, wherein the panline estimation is established using the sensor data indicative of an absolute shearer coordinate, a shearer orientation, and/or a shearer shoe position.
  11. The method according to claims 7-10, wherein the step of calculating (S60) an expected panline based on the predicted panline and the estimated panline comprises the step of merging the panline estimation and the panline prediction into a final result using an optimization algorithm, preferably a Kalman Filter.
  12. Longwall shearer system (1) comprising a longwall shearer (100), at least one pan , one or more hydraulic roof supports (8), the longwall shearer (100) being configured for use in the method according to claims 1-11, wherein the longwall shearer comprises a sensor device configured to retrieve sensor data indicative of an absolute shearer coordinate (x) and a shearer orientation (ψ, Θ, Φ) and configured to retrieve (S20) additional sensor data indicative of a relative shearer coordinate ( y ).

Description

Technical Field The present invention pertains to a method for determining a 3D position of a longwall shearer traveling on a panline along a longwall face of an underground coal mining panel. The present invention also pertains to a pan for a panline for use in such method. Further, the present invention also pertains to a longwall shearer system for use with such method, comprising a longwall shearer, at least one such pan, and one or more hydraulic roof support. Technological Background To extract material along a longwall face in an underground mine, longwall shearers with typically two cutting drums may be provided. As is known per se, the longwall shearer reciprocates on a panline along the longwall face to extract coal material with the two rotating cutting drums. Extracted coal material is dropped onto a face conveyor running aside the longwall face between face and shearer to transport the extracted coal material away for further processing. Hydraulic roof supports prevent roof material from collapsing on the longwall shearer including the panline and are further used to push the panline in a face advance, or coal retreat, direction. This usually happens right after the shearer passed a given pan segment of a pan line, giving a snake-like movement of the longwall shearer in the face advance direction. Behind the hydraulic roof support, the mined coal panel collapses. Identifying shearer position and orientation during operation is crucial for controlling, monitoring and post-processing the mining progress, especially when the aim is to obtain a so-called digital twin of the shearer during operation. However, position measurement possibilities underground and during operation of the longwall shearer are limited. Reasons are physical limitations due to dust, fog, vibrations, darkness, mountain pressure induced coal seam movements, but also statutory limitations, for example the prohibition of lasers during operation. Current positioning systems oftentimes use Inertial Navigation Systems, INS, also called Inertial Measurement Systems, IMS, for identifying a shearer orientation relative to an absolute coordinate system in the form of angles. Further, encoders or odometers are used for identifying an absolute shearer coordinate, giving one distance of the shearer relative to a fixed location in the coal seam. The INS usually comprises gyroscopes or other accelerationbased sensors. The INS outputs and the encoder outputs are then integrated and combined to a current shearer position. Due to the slow movements of the shearer and high vibrations, acceleration data for positioning are vastly inaccurate. The yaw angle, which is usually not represented in INS based orientation detection, suffers from substantial drift when determined using positioning technologies known from the state of the art. As a result, the obtained shearer positions, or shearer trajectories, are inaccurate. The method for determining a 3D position of a longwall shearer traveling on a panline along a longwall face of an underground coal mining panel, the pan for a panline, and the longwall shearer system solve one or more problems set forth above. From EP 1 276 969 B1 a mining machine is known, wherein coordinate positions of a rail means are measured and used to move the rail means to assume a desired profile. Summary Of The Invention Starting from the prior art, it is an objective of the present disclosure to provide a simple, reliable, cost-effective 3D positioning of a longwall shearer moving along a panline in an underground mining panel. This objective is solved by means of a method for determining a 3D position of a longwall shearer traveling on a panline along a longwall face of an underground coal mining panel with the features of claim 1, and a longwall shearer with the features of claim 2 Preferred embodiments are set forth in the present specification, the Figures as well as the dependent claims. Accordingly, a computer-implemented method for determining a 3D position of a longwall shearer traveling on a panline along a longwall face of an underground coal mining panel is provided, comprising the steps of retrieving sensor data indicative of an absolute shearer coordinate and a shearer orientation using a sensor device, retrieving additional sensor data indicative of the relative shearer coordinate using a sensor device, and calculating and rendering, using a computer, the 3D position and orientation of the longwall sheerer based on the absolute coordinate, the shearer orientation, and the relative shearer coordinate, wherein the calculation comprises outputting the 3D position and orientation of the longwall shearer with a panline. According to the invention, the absolute shearer coordinate comprises multiple encoder positions, and wherein the additional sensor data indicative of a relative coordinate comprises a retreat cylinder deflection in a face advance direction. Further, a pan for a panline is provided, configured to