Planned cutting method for medium-thickness coal seam

Abstract

The invention discloses a planned cutting method for a medium-thickness coal seam. The planned cutting method comprises the following steps: S1, dividing a preliminary cutting curve of a coal mining machine into a plurality of process sections; s2, performing data fitting by using a weighted average method to obtain planned cutting curves of all process sections; s3, the centralized control center issues the planned cutting curve to a centralized control module, and the centralized control module controls a coal mining machine to carry out coal mining operation according to the planned cutting curve; s4, connecting the hand-held terminal with the centralized control center, observing the operation conditions of the working face and the coal mining machine by working face inspection personnel in real time, recording abnormal points on the hand-held terminal when finding abnormal data, and adjusting the planned cutting curve of the coal mining machine in time; and S5, timely monitoring and recording the cut-through condition of the coal mining machine at the left and right limit positions by the personnel of the centralized control center, and judging whether the process section range of the planned cutting curve needs to be adjusted or not until the coal mining operation of the coal mining machine is completed.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of coal mining, in particular to a planning cutting method for medium-thick coal seams. BACKGROUND

[0002] Under the traditional coal mining mode, the operator needs to directly control the shearer at the underground working face to work. Due to the limitation of human eye observation and experience judgment, when facing complex geological conditions, it is easy to cause misoperation such as cutting top / bottom, resulting in invalid cutting, waste of coal resources and abnormal wear of cutting teeth. Therefore, it is necessary to solve the inherent defects of traditional manual control through shearer planning cutting technology.

[0003] The memory cutting technology is currently relatively mature in China. Its main implementation method is that the shearer control center memorizes the coal cutting path of the shearer driver, and then the control center automatically replicates the memorized coal cutting trajectory in the next cut. This method often appears learning interruption due to various reasons in the use process, and cannot obtain a standard cutting curve. At the same time, the shearer cannot integrate other equipment data of the working face, and the implementation effect is not good. According to the shearer body structure parameters and the coal cutting process to generate a cutting curve, this method has high dependence on the accuracy of the shearer sensor and cannot be corrected. The generated cutting curve is often not accurate enough, and the implementation difficulty is great. It is necessary to improve it. SUMMARY

[0004] The purpose of the present application is to provide a planning cutting method for medium-thick coal seams, which is simple to operate and improves the mining effect of the shearer.

[0005] In order to achieve the above purpose, the technical scheme of the present application is:

[0006] A planning cutting method for medium-thick coal seams, comprising the following steps:

[0007] S1, obtaining the historical position data and speed data of the shearer through the control center, and obtaining the preliminary cutting curve of the shearer according to the obtained historical position data and speed data of the shearer, and dividing the preliminary cutting curve into multiple process sections according to the advancing direction of the shearer;

[0008] S2, using the weighted average method to fit the data of each process section of the shearer preliminary cutting curve by using three different historical data, and filtering the abnormal points of the historical data to obtain the planning cutting curve of all process sections;

[0009] S3, the control center sends the planning cutting curve to the centralized control module, and the centralized control module sends the shearer speed instruction parameter and the shearer drum height instruction parameter according to the planning cutting curve and the real-time position of the shearer, and the shearer performs coal mining operation according to the shearer speed instruction parameter and the shearer drum height instruction parameter.

[0010] S4, connecting the handheld terminal with the centralized control center, the working face inspection personnel observing the working face and the shearer running in real time, recording the abnormal point on the handheld terminal when the abnormal data is found, and adjusting the planned cutting curve of the shearer in time;

[0011] S5, the centralized control center personnel monitoring and recording the cutting through condition of the shearer at the left and right limit positions in time, and judging whether the process section range of the planned cutting curve needs to be adjusted or not, until the coal mining operation of the shearer is completed.

[0012] Further, in the step S1, the abnormal data with a duration less than 1 second is excluded from the obtained historical position data and speed data of the shearer.

[0013] Further, in the step S1, the preliminary cutting curve of the shearer is divided into multiple process sections, including the following steps:

[0014] S11, setting the continuous time stamps of the shearer working time as T1, T2, T3, T4, T5……; the position corresponding to the support serial number of the shearer at the time stamps T1, T2, T3, T4, T5…… is N1, N2, N3, N4, N5……, the position corresponding to the support serial number of the left drum is NL1, NL2, NL3, NL4, NL5……, and the position corresponding to the support serial number of the right drum is NR1, NR2, NR3, NR4, NR5……;

[0015] S12, when the support serial number corresponding to the position of the left drum or the right drum at the time stamp T1 is less than the support serial number corresponding to the position of the left drum or the right drum at the time stamp T2, and the support serial number corresponding to the position of the left drum or the right drum at the time stamp T2 is greater than the support serial number corresponding to the position of the left drum or the right drum at the time stamp T3, or when the support serial number corresponding to the position of the left drum or the right drum at the time stamp T1 is greater than the support serial number corresponding to the position of the left drum or the right drum at the time stamp T2, and the support serial number corresponding to the position of the left drum or the right drum at the time stamp T2 is less than the support serial number corresponding to the position of the left drum or the right drum at the time stamp T3, it is determined that the time stamp T2 is a process section inflection point, and from the process section inflection point, when the support serial number corresponding to the position of the shearer continuously increases for more than three times, it is determined that the process section is a valid process section, otherwise, the process section inflection point is determined as an abnormal point and is filtered.

[0016] S13, repeating the step S12 until the preliminary cutting curve of the shearer is divided into multiple process sections.

[0017] Further, the step S2 specifically includes the following steps:

[0018] S21, according to the inclination sensor of the coal mining machine and the structural size, the cutting parameters of the coal mining machine at a support position and the corresponding support height are obtained, when the cutting parameters and the corresponding support height are greatly different, it is considered that the support position point is an abnormal point, and the abnormal point is deleted; otherwise, the cutting parameters and the corresponding support height are averaged to obtain the real drum historical height;

[0019] S22, the abnormal point processing operation is performed on the excessive fluctuation points in the three historical data;

[0020] S23, the three historical data are weighted and averaged to obtain a new cutting curve, Hermite interpolation method is used to complete and fit the missing points in the new cutting curve, and finally the planning cutting curve of all process sections is obtained.

[0021] Further, in the step S22, the abnormal point processing operation includes the following steps:

[0022] S221, set the deviation threshold value as E, and the set of values of all points in the process section is map{V1, V2, V3…}, and the number of elements in the map is K;

[0023] S222, all points in the process section are divided into different sets map1{N1, N5…}, map2{N2, N6…}, map3{N9, N11…}…… according to the same value and different support numbers as the standard;

[0024] S223, compare each value in the set map1 with other values in the set map1 in turn, obtain the difference value D, if D>E, add 1 to the abnormal sensitive radix M, and after the traversal is completed, if M>0.9K, it is determined that the difference of this point is too large, and the point is removed;

[0025] S224, according to step S223, the points with too large difference in the set map2, the set map3…… are removed in turn.

[0026] Further, in the step S23, the missing points in the new cutting curve are completed and fitted, including the following steps:

[0027] S231, set the support serial numbers in the process section as x0, x1,…, xn in turn, and the support height values as y0, y1,…, yn in turn;

[0028] S232, traverse all support serial numbers, and mark the missing point set as M={xm};

[0029] S233, for each non-missing point xi, calculate its derivative value yi′:

[0030] Forward difference:

[0031]

[0032] Backward difference:

[0033]

[0034] Central difference:

[0035]

[0036] S234. For missing points, first find the previous non-missing point (xa, ya), then find the next non-missing point (xb, yb), and finally extract the derivative values ​​ya′ and yb′ of the two non-missing points.

[0037] S235. On the interval [xa,xb], construct an interpolation polynomial using the non-missing points (xa,ya,ya′) and (xb,yb,yb′), and calculate it as follows:

[0038] H(x m )=y a ·(1-3t 2 +2t 3 )+y b ·(3t 2 -2t 3 )+y′ a ·h··(t-2t 2 +t 3 )+y′ b ·h·(-t 2 +t 3 );

[0039] Where h = x b -x a , 1-3t 2 +2t 3 This indicates the height weight of the preceding non-missing point; 3t 2 -2t 3 h(t-2t) represents the height weight of the next non-missing point. 2 +t 3 ): represents the derivative weight of the previous non-missing point; h(-t) 2 +t 3 ) represents the derivative weight of the next non-missing point.

[0040] Furthermore, the abnormal data in step S4 includes information on manual intervention and information on the working surface.

[0041] Furthermore, the step S5 of monitoring and recording the cutting penetration status of the coal mining machine at the left and right extreme positions includes the following steps:

[0042] S51, limit the magnet encoder position of the coal mining machine as the limit value of the process section, and as the limit position of the coal mining machine process section planning;

[0043] S52, install fixed point camera at the left and right limit positions of the working face, monitor and record the left and right limit positions of the coal mining machine through the fixed point camera when the coal mining machine approaches the left and right limit positions;

[0044] S53, the planning cutting operator judges whether the left and right limit positions have large deviations according to the monitoring picture, and judges whether the cutting position of the coal mining machine needs to be adjusted.

[0045] Compared with the prior art, the application has the advantages and positive effects that:

[0046] The application combines the centralized control center, handheld terminal, working face camera and coal mining machine for planning, and at the same time, it removes and corrects the abnormal points in the cutting curve, fills and fits the missing points in the cutting curve through the Hermite interpolation method, and finally obtains a more accurate planned cutting curve; it is more accurate in data, and is convenient for accurate control of the coal mining operation of the coal mining machine, effectively improves the implementation effect of the coal mining operation of the coal mining machine, avoids the conditions of invalid cutting, coal resource waste and abnormal wear of cutting teeth caused by misoperation such as cutting top / cutting bottom of the coal mining machine in the coal mining operation process, and brings convenience to the mining operation of the coal mine. BRIEF DESCRIPTION OF DRAWINGS

[0047] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0048] Figure 1 The control logic framework of the centralized control center for the coal mining machine;

[0049] Figure 2 The connection logic diagram of the handheld terminal and the coal mining machine. DETAILED DESCRIPTION

[0050] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, any modification, equivalent replacement, improvement, etc. made by any person of ordinary skill in the art without creative work should be included in the protection scope of the present application.

[0051] The present embodiment discloses a planning cutting method for medium-thick coal seams, and the steps are as follows:

[0052] I. The centralized control system obtains historical position data and speed data of the coal mining machine, and according to the data, the cutting curve of the coal mining machine is divided into multiple process sections according to the advancing direction of the coal mining machine.

[0053] (1) The sensor abnormal values (such as interference points with speed suddenly changing to 0 and duration <1 second) in the historical position data and speed data are removed.

[0054] (2) Set continuous time stamps T1, T2, T3, T4, T5, and corresponding parameters of the coal mining machine, i.e. support numbers N1, N2, N3, N4, N5, where the coal mining machine is located, support numbers NL1, NL2, NL3, NL4, NL5, where the left drum is located, and support numbers NR1, NR2, NR3, NR4, NR5, where the right drum is located.

[0055] For example, the support numbers of the left drum and the right drum on the time stamps T1, T2, and T3 appear T1

[0056] II. For each process section, three different historical data are applied again, and the weighted average value method is used for data fitting, and at the same time, the historical data are filtered for abnormal points to obtain the cutting curve of the process section.

[0057] (1) According to the inclination sensor and the structure size of the coal mining machine, the cutting parameters of the coal mining machine in a support are obtained, and the corresponding support height is obtained. If the difference between the two data is large, it is considered as an abnormal point, and the point is deleted, otherwise, the average value of the two is taken as the real historical height of the drum. According to the data information reported by the handheld terminal tablet and the remote controller of the coal mining machine, the rib spalling points of the working face are removed.

[0058] (2) The abnormal points of the three historical data are processed.

[0059] The normal cutting curve should be continuous, most values fluctuate around the mean value, or gently rise or fall, when the sensor fails or the working face appears abnormal conditions such as slice, the curve will appear large fluctuation, and these points need to be excluded. Therefore, the mean method, normal distribution and other methods cannot be used to exclude abnormal points. The application proposes the following algorithm to exclude abnormal points:

[0060] Suppose that the deviation from most values is greater than E, it is considered to be abnormal, the set of values of all points is map{V1, V2, V3…}, and the number of elements in map is K; all points are divided into different sets map1{N1, N5…} map2{N2, N6…} map3{N9, N11…}…… according to the same value and different frame numbers.

[0061] Traverse each value in map, compare the value with other values in map, obtain the difference D, if D>E, add 1 to the abnormal sensitive radix M (M initial value is 0), after traversal, if M>0.9K, it is determined that the point is too different from most points, and is considered to be an abnormal point, at the same time, in order to avoid too much data being filtered, the threshold parameter P is set, that is, at most P data will be excluded. According to the above steps, the abnormal points can be excluded, and the correct rising and falling trend of data is retained.

[0062] (3) The three historical data are weighted and averaged to obtain a new cutting curve, some abnormal points are excluded in the above steps, and the recorded cutting curve also has missing points, the application uses Hermite interpolation method to fit the cutting curve and complete the missing points.

[0063] 1. Suppose that the support serial numbers in the cutting process section of the coal mining machine are x0, x1,…, xn, all are integers, and the support height value sequence is y0, y1,…, yn (some points are missing).

[0064] 2. Traverse the support number, mark the missing point set M={xm} (such as x2, x5 missing);

[0065] 3. Calculate the derivative value y'i of each non-missing point xi:

[0066] Forward difference (first point):

[0067]

[0068] Backward difference (last point):

[0069]

[0070] Central difference (middle point):

[0071]

[0072] 4. For missing point xm∈M: first find the previous known non-missing point (xa,ya) (the largest known point with a lower bracket number than xm), then find the next known non-missing point (xb,yb) (the smallest known point with a higher bracket number than xm), and finally extract the derivatives: ya'(already calculated in step 3), yb'(already calculated in step 3).

[0073] For example: if x1,x2 are missing and x3 and x4 are known, then use the interval [x3,x4] for both x1 and x2.

[0074] 5. On the interval [xa,xb], use the nodes (xa,ya,ya') and (xb,yb,yb') to construct the interpolation polynomial:

[0075] H(x m ) = y a ·(1-3t 2 +2t 3 )+y b ·(3t 2 -2t 3 )+y′ a ·h·(t-2t 2 +t 3 )+y′ b ·h·(-t 2 +t 3 );

[0076] Substitute t and the known values to directly calculate H(xm).

[0077] where h = x b -x a ,

[0078]

[0079] 1-3t 2 +2t 3 : represents the front point height weight;

[0080] 3t 2 -2t 3 : represents the back point height weight;

[0081] h(t-2t 2 +t 3 ): represents the front point derivative weight;

[0082] h(-t 2 +t 3 ): back point derivative weight.

[0083] Three, the centralized control center plans the cutting curve of the shearer, and issues the cutting curve to the centralized control module; the centralized control module issues the shearer speed and drum height instructions to the shearer according to the planned cutting curve and the real-time shearer position; the shearer adjusts the speed and drum to the target value according to the command parameters and the working face conditions; the control process is as shown in Figure 1 . .

[0084] Four, the working face inspection personnel observe the working face and the shearer operation in real time, record the abnormal points on the terminal when abnormal data is found, and can also adjust the cutting curve of the subsequent shearer in time; the control process is as shown in Figure 2 . .

[0085] The abnormal data mainly includes manual intervention information and working face rib spalling information; the shearer can be intervened by the shearer remote control, and the planned curve of the area not passed by the shearer can be modified in real time through the super terminal tablet to enter the next cut; the above information assists the centralized control center to automatically generate the planned cutting curve. .

[0086] Five, the centralized control center personnel dispatch the centralized control center on the ground, can intervene the shearer in time according to the device data and camera data of the centralized control interface, and record the adjustment of the shearer in the end-to-end cutting position for accurate planning of the cutting curve of the next cut. .

[0087] 1. The position of the shearer limit magnet encoder is used as the limit value of the process section, and as the limit position of the shearer process section planning. .

[0088] 2. Fixed point cameras are installed at the left and right limit positions of the working face; when the shearer approaches the limit position, the camera picture pops up on the planned cutting monitoring software; the lens is aimed at the direction of the shearer; the planned cutting operator can judge whether the shearer needs to be intervened according to the picture data and the centralized control data, and whether the limit position deviates greatly, whether the process section range of the shearer needs to be adjusted. .

[0089] The present application combines the centralized control center, the handheld terminal, the working face camera and the shearer for planning, and corrects the abnormal points in the cutting curve; the missing points in the cutting curve are completed and fitted by the Hermite interpolation method; finally, a more accurate planned cutting curve is obtained; the data is more accurate, which is convenient for accurate control of the shearing operation of the shearer, effectively improves the implementation effect of the shearing operation of the shearer, avoids the invalid cutting, coal resource waste and abnormal wear of the cutting tooth caused by the misoperation of the shearer in the shearing operation process, and brings convenience to the mining operation of the coal mine.

Claims

1. A planning and cutting method for medium-thick coal seams, characterized in that: The method comprises the following steps: S1, obtaining historical position data and speed data of the coal mining machine through the centralized control center, obtaining a preliminary cutting curve of the coal mining machine according to the obtained historical position data and speed data of the coal mining machine, and dividing the preliminary cutting curve into a plurality of process sections according to the advancing direction of the coal mining machine; S2, performing data fitting on the preliminary cutting curve of the coal mining machine in each process section by using a weighted average method and filtering abnormal points in the historical data, and obtaining a planned cutting curve of all the process sections; S3, the centralized control center sends the planned cutting curve to the centralized control module, the centralized control module sends a speed instruction parameter and a drum height instruction parameter of the coal mining machine according to the planned cutting curve and the real-time position of the coal mining machine, and the coal mining machine performs the coal mining operation according to the speed instruction parameter and the drum height instruction parameter of the coal mining machine; S4, connecting the handheld terminal with the centralized control center, and observing the working face and the operation of the coal mining machine by the working face inspection personnel in real time, recording abnormal points on the handheld terminal when abnormal data is found, and adjusting the planned cutting curve of the coal mining machine in time; S5, the personnel of the centralized control center monitor and record the cutting-through condition of the coal mining machine at the left and right limit positions, and judge whether the process section range of the planned cutting curve needs to be adjusted, until the coal mining operation of the coal mining machine is completed.

2. The method of planning a cut for a medium thick coal seam as claimed in claim 1, wherein: In the step S1, the abnormal data with a duration less than 1 second is excluded from the obtained historical position data and speed data of the coal mining machine.

3. The method of planning a cut for a medium thick coal seam as claimed in claim 2, wherein: In the step S1, the preliminary cutting curve of the coal mining machine is divided into a plurality of process sections, which comprises the following steps: S11, setting continuous time stamps T1, T2, T3, T4, T5…… when the coal mining machine works, and the position corresponding to the time stamp T1, T2, T3, T4, T5…… of the coal mining machine is the support serial number N1, N2, N3, N4, N5……, the position corresponding to the time stamp T1, T2, T3, T4, T5…… of the left drum is the support serial number NL1, NL2, NL3, NL4, NL5……, and the position corresponding to the time stamp T1, T2, T3, T4, T5…… of the right drum is the support serial number NR1, NR2, NR3, NR4, NR5……; S12, when the support serial number corresponding to the position of the left drum or the right drum at the time stamp T1 is less than the support serial number corresponding to the position of the left drum or the right drum at the time stamp T2, and the support serial number corresponding to the position of the left drum or the right drum at the time stamp T2 is greater than the support serial number corresponding to the position of the left drum or the right drum at the time stamp T3, or when the support serial number corresponding to the position of the left drum or the right drum at the time stamp T1 is greater than the support serial number corresponding to the position of the left drum or the right drum at the time stamp T2, and the support serial number corresponding to the position of the left drum or the right drum at the time stamp T2 is less than the support serial number corresponding to the position of the left drum or the right drum at the time stamp T3, it is determined that the time stamp T2 is a process section inflection point, and when the support serial number corresponding to the position of the coal mining machine continuously increases by more than three from the process section inflection point, it is determined that the process section is a valid process section, otherwise, the process section inflection point is determined as an abnormal point and is filtered; S13, repeating the step S12 until the preliminary cutting curve of the coal mining machine is divided into a plurality of process sections.

4. The method of planning a cut for a medium thick coal seam as claimed in claim 3, wherein: The step S2 specifically comprises the following steps: S21, obtaining the cutting parameters and corresponding support height of the coal winning machine at a certain support position according to the inclination sensor and structural size of the coal winning machine, when the cutting parameters and corresponding support height are quite different, it is considered that the support position point is an abnormal point, and the abnormal point is deleted; otherwise, the average value of the cutting parameters and corresponding support height is taken as the real historical height of the drum; S22, performing an abnormal point processing operation on the excessive fluctuation points in the three historical data; S23, performing a weighted average processing on the three historical data to obtain a new cutting curve, using Hermite interpolation method to complete the fitting of the missing points in the new cutting curve, and finally obtaining the planning cutting curve of all process sections.

5. The method of planning a cut for a medium thick coal seam as claimed in claim 4, wherein: In the step S22, the abnormal point processing operation comprises the following steps: S221, setting a deviation threshold value E, and a set of values of all points in the process section is map{V1, V2, V3…}, and it is assumed that the number of elements in the map is K; S222, dividing all points in the process section into different sets map1{N1, N5…}, map2{N2, N6…}, map3{N9, N11…}…… according to the same value and different support numbers as the standard; S223, comparing each value in the set map1 with other values in the set map1 in turn, obtaining the difference value D, if D>E, then the abnormal sensitive radix M is added by 1, and after the traversal is completed, if M>0.9K, it is determined that the difference of the point is too large, and the point is removed; S224, according to the step S223, the points with too large difference in the set map2, the set map3…… are removed in turn.

6. The method of planning a cut for a medium thick coal seam as claimed in claim 5, wherein: In the step S23, the missing points in the new cutting curve are completed and fitted, comprising the following steps: S231, setting the support numbers in the process section as x0, x1,…, xn in turn, and the support height values as y0, y1,…, yn in turn; S232, traversing all support numbers, and marking the missing point set as M={xm}; S233, calculating the derivative value y'i of each non-missing point xi: Forward difference: Backward difference: Central difference: S234, for the missing point, firstly finding the previous non-missing point (xa, ya) of the missing point, then finding the next non-missing point (xb, yb) of the missing point, and finally extracting the derivative values ya' and yb' of the two non-missing points; S235, in the interval [xa, xb], using the non-missing points (xa, ya, ya') and (xb, yb, yb') to construct an interpolation polynomial, and the calculation formula is: H(x m ) = y a ·(1 - 3t 2 + 2t 3 ) + y b • (3t 2 - 2t 3 ) + y' a • h • (t - 2t 2 + t 3 ) + y' - x' b • h • (-t 2 + t 3 ); wherein, 1 - 3t 2 + 2t 3 h(t) represents the height weight of the previous non-missing point; 3t 2 - 2t 3 h(t - 2t) represents the height weight of the next non-missing point; h(t 2 + t 3 h(t) represents the derivative weight of the previous non-missing point; h(-t 2 + t 3 h(t) represents the derivative weight of the next non-missing point.

7. The method of planning a cut for a medium thick coal seam as claimed in claim 6, wherein: The abnormal data in the step S4 comprises artificial intervention information and face spalling information.

8. The method of planning a cut for a medium thick coal seam as claimed in claim 7, wherein: In the step S5, the cutting through conditions of the coal winning machine at the left and right limit positions are monitored and recorded, comprising the following steps: S51, taking the position of the limit magnet encoder of the coal winning machine as the limit value of the process section, and as the limit position of the process section planning of the coal winning machine; S52, installing a fixed point camera at the left and right limit positions of the working face, and when the coal winning machine approaches the left and right limit positions, the left and right limit positions of the coal winning machine are monitored and recorded through the fixed point camera. S53, the planning cutting operator determines whether a large deviation occurs in the left and right limit positions according to the monitoring picture, and determines whether the shearing position of the coal mining machine needs to be adjusted.

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