阅读说明：本技术 基于惯导系统的煤矿综采工作面自动调直系统及方法 (Coal mine fully mechanized coal mining face automatic straightening system and method based on inertial navigation system ) 是由 李国威 常亚军 连东辉 郭建京 梁涛 崔科飞 马勇超 李红卫 于 2020-03-20 设计创作，主要内容包括：本发明公开了一种基于惯导系统的煤矿综采工作面自动调直系统及方法,包括顺槽主控计算机,无线通信基站,用于检测移架距离的行程传感器,设置在采煤机上的惯导系统和采煤机行走编码器。惯导系统将收到的采煤机行走编码器数据后生成采煤机位置信息后通过CAN网传输给顺槽主控计算机。顺槽主控计算机将收到的采煤机位置坐标信息生成采煤机行走轮廓曲线,计算出每个液压支架修正量和液压支架实际移架距离,通过CAN网将移架控制指令发送给每台液压支架上的电液控制器进行移架控制,完成综采工作面自动调直。本发明优点是操作简单、响应快、移架控制准确度高,不受综采工作面复杂环境如光照不足、煤尘大等的影响,抗干扰性强。(The invention discloses an inertial navigation system-based automatic alignment system and method for a fully mechanized coal mining face of a coal mine. The inertial navigation system generates coal mining machine position information after receiving the coal mining machine walking encoder data and transmits the information to the crossheading main control computer through the CAN network. And the crossheading main control computer generates a coal mining machine walking profile curve according to the received position coordinate information of the coal mining machine, calculates the correction amount of each hydraulic support and the actual support moving distance of the hydraulic support, and sends a support moving control instruction to an electro-hydraulic controller on each hydraulic support through a CAN (controller area network) network to perform support moving control so as to finish automatic straightening of the fully mechanized mining face. The invention has the advantages of simple operation, quick response, high control accuracy of the moving frame, no influence of complex environment of the fully mechanized coal mining face, such as insufficient illumination, large coal dust and the like, and strong anti-interference performance.)

1. The utility model provides a colliery is combined and is adopted automatic alignment system of working face based on inertial navigation system which characterized in that: the system comprises a gate main control computer, a wireless communication base station of the fully mechanized mining face, a stroke sensor arranged on each hydraulic support, an inertial navigation system arranged on a coal mining machine and a coal mining machine walking encoder; the inertial navigation system is communicated with the wireless communication base station in a wireless mode, the wireless communication base station is communicated with the crossheading main control computer through a CAN (controller area network), and the coal mining machine walking encoder is communicated with the inertial navigation system in a wired mode and is communicated with the crossheading main control computer in a carrier wave mode; and the crossheading main control computer is communicated with the electro-hydraulic controller on each hydraulic support through a CAN (controller area network), and the electro-hydraulic controller is used for receiving a control instruction sent by the crossheading main control computer to control the hydraulic supports.

2. The straightening method of the automatic straightening system of the coal mine fully mechanized coal mining face according to claim 1, characterized by comprising the following steps: the method comprises the following steps:

step 1, establishing an inertial navigation system model:

step 1.1, installing the inertial navigation system at the middle position of the body of the coal mining machine, and setting the installation position as an original point O;

step 1.2, establishing an inertial navigation system coordinate system: after the inertial navigation system is installed, setting an inertial navigation system navigation coordinate system (O, X, Y, Z), wherein the navigation coordinate system takes the installation position of the inertial navigation system as an original point O, the direction of the original point O pointing to the walking direction of the coal mining machine is the positive direction of an X axis, the direction of the original point O pointing to the propelling direction of the fully mechanized coal mining face is the positive direction of a Y axis, the direction of the original point O vertically upwards is the positive direction of a Z axis, and the Z axis is set to be 0;

step 1.3, uploading the coordinates of the walking track of the coal mining machine: the coal mining machine walking encoder will measureThe parameters are transmitted into the inertial navigation system to calculate the real-time accurate walking position coordinate (X) of the coal mining machine in real time_T，Y_T，Z_T) The information is uploaded to the crossheading main control computer;

step 2, forming a walking profile curve of the coal mining machine: real-time walking position coordinate (X) of the coal mining machine_T，Y_T，Z_T) Is a spatial coordinate in a coordinate system (OX, OY, OZ), and Z_T＝0；

Step 2.1, identifying the complete profile curve of the coal mining machine during walking: identifying a coal mining machine walking profile curve by setting a machine head mark point and a machine tail mark point, namely judging whether the walking track of the coal mining machine is complete or not;

step 2.2, splicing the traveling track segments of the coal mining machine: when the measurement process of the coal mining machine walking encoder is interrupted, the inertial navigation system records the walking track of the coal mining machine again from the original point O, splices the walking track of the coal mining machine, and records the coordinate point (X) of the coal mining machine at the moment of interruption t_t，Y_t) Commanding all coal mining machine coordinate points recorded againRespectively with said coordinate points (X)_t，Y_t) Adding to obtain a complete coal mining machine walking track measurement curve, wherein i is 1,2, 3.

Step 2.3, coordinate point optimization:

step 2.3.1, dividing the generated coordinate points of the walking track measurement curve of the coal mining machine at equal intervals, setting the division interval to L, and dividing all the coordinate points (X) of the coal mining machine in each equal interval_i，Y_i) Arithmetic mean is performed to generate a coordinate point (X)_L，Y_L) Representing the coordinate points of the interval area, and skipping the interval area if the number of the generated coordinate points of the interval area is 0;

step 2.3.2, adopting cubic spline interpolation method and natural boundary condition to represent all the equally spaced regions (X)_L，Y_L) Curve fitting is carried out to generate a preliminary contour line l 'of the coal mining machine walking curve'₀；

Step 2.4Rotating the preliminary contour line l'₀And (3) to a horizontal state: using the connecting line between the head mark point and the tail mark point as the actual contour reference line₀Extended to both sides, and the preliminary contour line l'₀By rotating the formula: x_R＝X_Tcos(β)+Y_Tsin(β)、Y_R＝Y_Tcos(β)-X_Tsin (β) is rotated to the horizontal direction, i.e. let the actual profile reference line l₀Coincident with the X-axis, where the coordinate point (X)_R，Y_R) For the rotated shearer position coordinate point, (X)_T，Y_T) For the real-time shearer position coordinate point, β is the actual profile reference line l₀Angle to the X-axis, by reference line l of the actual profile₀Obtaining the slope of the slope by inverting; by means of₁Denotes the post-rotation reference line, < l >'₁Denotes the preliminary profile curve after rotation, l ″)₁Indicating the line of expected result after rotation, and the reference line l after rotation₁And automatically straightening the expected result line l' after rotation₁Are all in contact with X_TThe axes are parallel;

step 2.5, smoothing: adopting a secondary exponential moving average algorithm to carry out comparison on the rotated primary profile curve l'₁Smoothing is carried out to obtain a profile curve l 'of the coal mining machine for calculating the correction amount RPC of each hydraulic support'₂；

Step 2.6, setting the maximum frame moving distance D_maxAnd a minimum racking distance D_minSaid maximum racking distance D_maxThe maximum moving distance allowed by each hydraulic support when the hydraulic supports move the supports in the full range, and the minimum moving distance D_minThe minimum moving distance allowed by the hydraulic support;

step 2.7, setting the automatic alignment error d: calculating a coal mining machine walking profile curve l'₂The middle highest point A and the lowest point B are respectively connected with a reference line l after rotation₁Perpendicular distance d between_h、d_lAnd then: d＝|d_h|+|d_l|；

When d isWhen the diameter is less than or equal to 100mm, the self-alignment error is within the allowable range;

step 3, calculating alignment parameters:

step 3.1, setting correction RPC: the RPC maximum value is RPC_max0, minimum correction amount at the lowest point B, RPC_Bmin＝D_min-D_maxThe correction amount at the maximum point A is RPC_A＝D_min-D_maxFor profile curve l'₂Setting the vertical distance from the point M to the lowest point B as D_MAccording to the formula: RPC_M＝RPC_A×(D_M/D_max) I.e. a profile curve l 'can be calculated'₂Correction amount RPC of any point M_M；

Step 3.2, calculating the actual frame moving distance: according to all the reference lines l uniformly distributed after rotation₁The width and the spacing distance of the upper hydraulic support are determined, and the position of the middle point of each hydraulic support is determined to be in a profile curve l'₂Abscissa X of the coordinate system_kK is 1,2,3 … k, and k is the total number of the hydraulic supports; from said abscissa X_kThe vertical distance D from the midpoint of each hydraulic support to the lowest point B can be calculated_kAnd further calculating to obtain the correction RPC of the midpoint of each hydraulic support_k(ii) a According to the calculated correction RPC_kFrom the formula: m is_k＝D_max+RPC_kAnd calculating to obtain the actual distance m of each hydraulic support moving frame_k；

And 4, realizing automatic straightening of the fully mechanized coal mining face: actual distance m for moving hydraulic support by gate main control computer_kThe hydraulic support is issued to the electro-hydraulic controller corresponding to the hydraulic support, and the electro-hydraulic controller controls the corresponding hydraulic support to move according to the measuring range of the stroke sensor;

step 5, before the fully mechanized mining face is automatically straightened, firstly, the walking profile curve l 'of the coal mining machine is subjected to'₂Performing a measurement, i.e. completing step 2, after which d is determinedWhether or not it is less than or equal to 100mm, if dIf d is less than or equal to 100mm, the uncorrecting is continuously measured in the next mining cycle, namely step 2 is continuously executed, if d isIf the length is more than 1000m, executing the step 3 to the step 5 in the next mining cycle to realize the automatic alignment of the fully mechanized coal mining face, and circulating the stepsUp to d≤100mm。

3. The straightening method of the automatic straightening system of the fully mechanized coal mining face according to claim 2, characterized in that in step 2.3.1, the generated coordinate points of the walking track measurement curve of the coal mining machine are divided at equal intervals of 0.5m, namely the set division interval L is 0.5 m.

4. The straightening method of the automatic straightening system of the fully mechanized coal mining face of the coal mine according to claim 2, characterized by comprising the following steps: in step 2.6, the set maximum frame moving distance D_maxEqual to the cut depth of the shearer drum; set the minimum racking distance D_minIs half of the cutting depth of the roller of the coal mining machine.

5. The straightening method of the automatic straightening system of the fully mechanized coal mining face of the coal mine according to claim 2, characterized by comprising the following steps: in step 4, the electro-hydraulic controller controls the corresponding hydraulic support to move according to the measuring range of the stroke sensor; and recording the frame moving time of each hydraulic support in the frame moving process, and when the individual stroke sensor fails, moving the hydraulic support according to the time T to ensure the smooth frame moving, wherein the T is the average value of the frame moving time of the left and right adjacent frames of the hydraulic support.

Technical Field

The invention relates to the field of coal mining, in particular to a coal mine fully mechanized coal mining face automatic straightening system and method based on an inertial navigation system.

Background

The intellectualization and the unmanned of the coal mine fully-mechanized working face are the development trend of the current coal mining field, and how to automatically control the coal mine fully-mechanized working face to have better straightness is always a core problem which restricts the development of the research direction. In addition, according to the regulation of coal mine safety regulations, the fully mechanized coal mining face of the coal mine is required to realize three straightness, namely, the hydraulic support, the scraper conveyor and the coal wall are ensured to be straight. As the coal mining machine is arranged on the scraper conveyor, the straightness of the scraper conveyor is kept to be adjusted by the hydraulic support, and the key of whether the hydraulic support can be accurately straightened is that the straightness of the working face is detected and straightening parameters are acquired accurately. Therefore, the key to automatically realize the three-straight state is the straightness detection technology of the working face and the acquisition of the alignment parameters.

In recent years, some enterprises and colleges in China also successively provide some coal mine fully mechanized coal mining face straightening systems and methods. The Chinese invention patent (patent number: 201711232670.6) discloses that a rapid inspection platform with cameras arranged at the edge of a cable groove of a working face is adopted to acquire videos, and then a moving target tracking algorithm is used to calculate the moving track of a video acquisition device; however, due to the characteristics of insufficient illumination and large coal dust on the fully mechanized coal mining face, the image processing technology is difficult to apply to the fully mechanized coal mining face, and the measurement error is large. The Chinese invention patent (patent number: 201910493976.X) discloses that a rotatable laser induction distance measuring device is arranged on each hydraulic support of a fully mechanized mining face, and a laser induction receiving device is arranged on a scraper machine to obtain the straightness of the hydraulic support and the scraper machine of the working face. The Chinese patent of invention (patent number: 201610128789.8) discloses that the straightness of a scraper conveyor is ensured by measuring the distance between the scraper conveyor and a coal wall by using an ultrasonic sensor, but the coal wall has the conditions of rib spalling and soft coal layer, which can cause larger error of the measurement result and cause excessive bending damage of equipment, and meanwhile, the distance between the scraper conveyor and the coal wall cannot effectively reflect the straightness of the scraper conveyor.

In summary, the existing straightening system and method for the fully-mechanized coal mining face of the coal mine have large limitations and are limited by complex environments such as insufficient illumination of the fully-mechanized coal mining face, large coal dust, limited space and the like, and the requirements of intellectualization and automation of the fully-mechanized coal mining face cannot be met, so that the straightening of the fully-mechanized coal mining face of the coal mine in actual production mainly depends on manual operation.

Disclosure of Invention

The invention aims to provide an automatic straightening system of a coal mine fully mechanized coal mining face based on an inertial navigation system, and the invention also aims to provide a straightening method of the straightening system.

In order to achieve the purpose, the invention adopts the following technical scheme:

the coal mine fully-mechanized coal mining face automatic straightening system based on the inertial navigation system comprises a crossheading main control computer, a fully-mechanized coal mining face wireless communication base station, a stroke sensor arranged on each hydraulic support, an inertial navigation system arranged on a coal mining machine and a coal mining machine walking encoder; the inertial navigation system is communicated with the wireless communication base station in a wireless mode, the wireless communication base station is communicated with the crossheading main control computer through a CAN (controller area network), and the coal mining machine walking encoder is communicated with the inertial navigation system in a wired mode and is communicated with the crossheading main control computer in a carrier wave mode; and the crossheading main control computer is communicated with the electro-hydraulic controller on each hydraulic support through a CAN (controller area network), and the electro-hydraulic controller is used for receiving a control instruction sent by the crossheading main control computer to control the hydraulic supports.

The invention relates to a straightening method of an automatic straightening system of a fully mechanized coal mining face, which comprises the following steps:

step 1, establishing an inertial navigation system model:

step 1.1, installing the inertial navigation system at a middle position outside a body of the coal mining machine, and setting the installation position as an original point O;

step 1.2, establishing an inertial navigation system coordinate system: after the inertial navigation system is installed, setting an inertial navigation system navigation coordinate system (O, X, Y, Z), wherein the navigation coordinate system takes the installation position of the inertial navigation system as an original point O, the direction of the original point O pointing to the walking direction of the coal mining machine is the positive direction of an X axis, the direction of the original point O pointing to the propelling direction of the fully mechanized coal mining face is the positive direction of a Y axis, the direction of the original point O vertically upwards is the positive direction of a Z axis, and the Z axis is set to be 0;

step 1.3, uploading the coordinates of the walking track of the coal mining machine: the coal mining machine walking encoder transmits the measured parameters into the inertial navigation system to calculate the accurate real-time walking position coordinate (X) of the coal mining machine in real time_T，Y_T，Z_T) The information is uploaded to the crossheading main control computer;

step 2, forming a walking profile curve of the coal mining machine: real-time walking position coordinate (X) of the coal mining machine_T，Y_T，Z_T) Is a spatial coordinate in a coordinate system (OX, OY, OZ), and Z_T＝0；

Step 2.1, identifying the complete profile curve of the coal mining machine during walking: identifying a coal mining machine walking profile curve by setting a machine head mark point and a machine tail mark point, namely judging whether the walking track of the coal mining machine is complete or not;

step 2.2, splicing the traveling track segments of the coal mining machine: when the measurement process of the coal mining machine walking encoder is interrupted, the inertial navigation system records the walking track of the coal mining machine again from the original point O, splices the walking track of the coal mining machine, and records the coordinate point (X) of the coal mining machine at the moment of interruption t_t,Y_t) Commanding all coal mining machine coordinate points recorded againRespectively with said coordinate points (X)_t,Y_t) Adding the obtained data to obtain a complete coal mining machine walking track measurement curve,i＝1,2,3…N；

step 2.3, coordinate point optimization:

step 2.3.1, dividing the generated coordinate points of the walking track measurement curve of the coal mining machine at equal intervals, setting the division interval to L, and dividing all the coordinate points (X) of the coal mining machine in each equal interval_l,Y_l) Arithmetic mean is performed to generate a coordinate point (X)_L,Y_L) Representing the coordinate points of the interval area, and skipping the interval area if the number of the generated coordinate points of the interval area is 0;

step 2.3.2, adopting cubic spline interpolation method and natural boundary condition to represent all the equally spaced regions (X)_L,Y_L) Curve fitting is carried out to generate a preliminary contour line l 'of the coal mining machine walking curve'₀；

Step 2.4, rotate the preliminary contour l'₀And (3) to a horizontal state: using the connecting line between the head mark point and the tail mark point as the actual contour reference line₀Extended to both sides, and the preliminary contour line l'₀By rotating the formula: x_R＝X_Tcos(β)+Y_Tsin(β)、Y_R＝Y_Tcos(β)-X_Tsin (β) is rotated to the horizontal direction, i.e. the actual profile reference line l₀Coincident with the X-axis, where the coordinate point (X)_R,Y_R) For the rotated shearer position coordinate point, (X)_T,Y_T) For the real-time shearer position coordinate point, β is the actual profile reference line l₀Angle to the X-axis, by reference line l of the actual profile₀Obtaining the slope of the slope by inverting; by means of₁Denotes the post-rotation reference line, < l >'₁Denotes the preliminary profile curve after rotation, l ″)₁Indicating the line of expected result after rotation, and the reference line l after rotation₁And automatically straightening the expected result line l' after rotation₁Are all in contact with X_TThe axes are parallel;

step 2.5, smoothing: adopting a secondary exponential moving average algorithm to carry out comparison on the rotated primary profile curve l'₁Smoothing is carried out to obtain a profile curve l 'of the coal mining machine for calculating the correction amount RPC of each hydraulic support'₂；

Step 2.6, setting the maximum frame moving distance D_maxAnd a minimum racking distance D_minSaid maximum racking distance D_maxThe maximum moving distance allowed by each hydraulic support when the hydraulic supports move the supports in the full range, and the minimum moving distance D_minThe minimum moving distance allowed by the hydraulic support;

step 2.7, setting the automatic alignment error d: calculating a coal mining machine walking profile curve l'₂The middle highest point A and the lowest point B are respectively connected with a reference line l after rotation₁Perpendicular distance d between_h、d_lAnd then: d＝|d_h|+|d_l|；

When d isWhen the diameter is less than or equal to 100mm, the self-alignment error is within the allowable range;

step 3, calculating alignment parameters:

step 3.1, setting correction RPC: the RPC maximum value is RPC_max0, minimum correction amount at the lowest point B, RPC_Bmin＝D_min-D_maxThe correction amount at the maximum point A is RPC_A＝D_min-D_maxFor profile curve l'₂Setting the vertical distance from the point M to the lowest point B as D_MAccording to the formula: RPC_M＝RPC_A×(D_M/D_max) I.e. a profile curve l 'can be calculated'₂Correction amount RPC of any point M_M；

Step 3.2, calculating the actual frame moving distance: according to all the reference lines l uniformly distributed after rotation₁The width and the spacing distance of the upper hydraulic support are determined, and the position of the middle point of each hydraulic support is determined to be in a profile curve l'₂Abscissa X of the coordinate system_kK is 1,2,3 … k, and k is the total number of the hydraulic supports; from said abscissa X_kThe vertical distance D from the midpoint of each hydraulic support to the lowest point B can be calculated_kAnd further calculating to obtain the correction RPC of the midpoint of each hydraulic support_k(ii) a According to the calculated correction RPC_kFrom the formula: m is_k＝D_max+RPC_kAnd calculating to obtain the moving frame of each hydraulic supportActual distance m of_k；

And 4, realizing automatic straightening of the fully mechanized coal mining face: actual distance m for moving hydraulic support by gate main control computer_kThe hydraulic support is issued to the electro-hydraulic controller corresponding to the hydraulic support, and the electro-hydraulic controller controls the corresponding hydraulic support to move according to the measuring range of the stroke sensor;

step 5, before the fully mechanized mining face is automatically straightened, firstly, the walking profile curve l 'of the coal mining machine is subjected to'₂Performing a measurement, i.e. completing step 2, after which d is determinedWhether or not it is less than or equal to 100mm, if dIf d is less than or equal to 100mm, the uncorrecting is continuously measured in the next mining cycle, namely step 2 is continuously executed, if d is>1000m, executing the steps 3 to 5 in the next mining cycle to realize automatic alignment of the fully mechanized coal mining face, and repeating the steps until d≤100mm。

Further, in step 2.3.1, the generated coordinate points of the coal mining machine travel track measurement curve are divided at equal intervals of 0.5m, that is, the set division interval L is equal to 0.5 m.

Further, in step 2.6, the maximum racking distance D is set_maxEqual to the cut depth of the shearer drum; set the minimum racking distance D_minIs half of the cutting depth of the roller of the coal mining machine.

Further, in step 4, the electro-hydraulic controller controls the corresponding hydraulic support to move according to the measuring range of the stroke sensor; and recording the frame moving time of each hydraulic support in the frame moving process, and when the individual stroke sensor fails, moving the hydraulic support according to the time T to ensure the smooth frame moving, wherein the T is the average value of the frame moving time of the left and right adjacent frames of the hydraulic support.

The advantages of the invention are embodied in the following aspects:

1, simple operation, quick response and high frame moving control accuracy.

And 2, the walking track of coal mining is detected and calculated by adopting the combination of strapdown inertial navigation and a coal mining machine encoder, the influence of complex environments of a fully mechanized coal mining face, such as insufficient illumination, large coal dust and the like is avoided, and the anti-interference performance is strong.

3, two methods for transmitting data of the stroke encoder of the coal mining machine and the strapdown inertial navigation are provided, and the problem that the coal mining machines produced by different manufacturers cannot directly transmit data with the strapdown inertial navigation is solved; the inertial navigation system and the coal mining machine walking encoder adopt a direct transmission mode, so that the real-time performance of generating the walking track of the coal mining machine is enhanced.

And 4, wireless base stations are adopted for wireless network coverage, the wireless base stations are connected through optical fibers, and the hydraulic support electro-hydraulic controller is connected with the crossheading main control computer through a CAN (controller area network), so that the reliability and the efficiency of data transmission are ensured.

And 5, the automatic straightening of the fully mechanized mining face adopts frame moving straightening, and the pushing sliding is carried out according to the full range when the hydraulic support pushes sliding, so that the automatic straightening operation of the fully mechanized mining face is simplified, and the precision and controllability of the automatic straightening are enhanced, because the moving stroke of the hydraulic moving frame is easier to control than the pushing sliding.

And 6, a machine head mark point, a machine tail mark point, a maximum frame moving distance and a minimum frame moving distance are set, so that the calculation process of the frame moving target value m is simplified, and the accuracy of the calculation result and the frame moving efficiency are improved.

And 7, the frame moving time of each hydraulic support is recorded, and when a certain hydraulic support stroke sensor breaks down, the frame can be moved and straightened according to the average value of the frame moving time of the left and right adjacent frames of the hydraulic support, so that the smooth operation of automatic straightening is ensured.

Drawings

FIG. 1 is a schematic diagram of the system of the present invention.

Fig. 2 is a schematic rotation diagram of the fully mechanized mining face of the present invention, and an arrow indicates a propelling direction of the fully mechanized mining face.

Fig. 3 is a schematic diagram of the straightening principle of the fully mechanized mining face of the invention, and an arrow indicates the advancing direction of the fully mechanized mining face.

Fig. 4 is a block flow diagram of the method of the present invention.

Detailed Description

The following describes embodiments of the present invention in detail with reference to the drawings, which are implemented on the premise of the technical solution of the present invention, and detailed embodiments and specific operation procedures are provided, but the scope of the present invention is not limited to the following embodiments.

As shown in figure 1, the coal mine fully-mechanized coal mining face automatic alignment system based on the inertial navigation system comprises a crossheading main control computer 1, wireless communication base stations 2 and 3 arranged at the end head and the end tail of the fully-mechanized coal mining face, wherein the wireless communication base stations 2 and 3 are communicated through an optical cable, each hydraulic support of the fully-mechanized coal mining face is provided with a stroke sensor for detecting the moving distance, and a strapdown inertial navigation system 5 and a coal mining machine walking encoder 6 which are arranged on a coal mining machine 4.

The coal mining machine walking encoder 6 has two data transmission modes: one way is to communicate with the strapdown inertial navigation system 5 directly by wire to transmit data to the strapdown inertial navigation system 5; the other mode is that the communication is carried out with the crossheading main control computer 1 in a carrier wave mode, and then the crossheading main control computer 1 transmits data to the strapdown inertial navigation system 5 through the CAN network and the wireless communication base stations 2 and 3.

The strapdown inertial navigation system 5 generates coal mining machine position information after receiving the coal mining machine walking encoder data, transmits the coal mining machine position information to the wireless communication base stations 2 and 3 in a wireless mode, and transmits the coal mining machine position information to the crossheading main control computer 1 through the CAN network by the wireless communication base stations 2 and 3. The crossheading main control computer 1 generates a coal mining machine walking profile curve from the received position coordinate information of the coal mining machine, calculates the correction amount of each hydraulic support and the actual support moving distance of the hydraulic support, and then sends a support moving control instruction to an electro-hydraulic controller on each hydraulic support through a CAN network. And each electro-hydraulic controller performs frame moving control on each hydraulic support according to the received control instruction to finish automatic straightening of the fully mechanized coal mining face.

As shown in fig. 1,2,3 and 4, the automatic straightening method for the fully mechanized coal mining face of the invention comprises the following steps:

step 1, establishing a strapdown inertial navigation system model:

step 1.1, installing a strapdown inertial navigation system 5 at a middle position outside a machine body of a coal mining machine 4, and setting the installation position as an original point O; before each work, the strapdown inertial navigation system 5 needs to be aligned to the origin O in a static state, so as to eliminate zero point deviation generated by the strapdown inertial navigation system 5 immediately after power-on or long-time operation.

Step 1.2, establishing a coordinate system of the strapdown inertial navigation system: after the installation of the strapdown inertial navigation system 5 is completed, a navigation coordinate system (O, X, Y, Z) of the strapdown inertial navigation system is set, the navigation coordinate system takes the installation position of the strapdown inertial navigation system 5 as an original point O, the direction of walking of the coal mining machine 4 through the original point O is the positive direction of an X axis, the direction of propelling of the fully mechanized coal mining face through the original point O is the positive direction of a Y axis, the direction of propelling of the fully mechanized coal mining face through the original point O is the positive direction of a Z axis vertically upwards, and the Z axis is set.

Step 1.3, uploading the coordinates of the walking track of the coal mining machine: the coal mining machine walking encoder 6 transmits the measured parameters into the strapdown inertial navigation system 5 to calculate the real-time walking position coordinate (X) of the accurate coal mining machine 4 in real time_T，Y_T，Z_T) And uploading the information to the crossheading main control computer 1.

Step 2, forming a walking profile curve of the coal mining machine: real-time walking position coordinate (X) of coal mining machine 4_T，Y_T，Z_T) Is a spatial coordinate in a coordinate system (OX, OY, OZ), and Z_T＝0。

Step 2.1, identifying the complete profile curve of the coal mining machine during walking: as shown in fig. 3, the curve of the traveling profile of the coal mining machine 4 is identified by setting a nose mark point c and a tail mark point d, that is, whether the traveling track of the coal mining machine 4 is complete is determined. In actual production, the nose mark point c is generally arranged at a position which is away from the end a of the fully mechanized mining face by ten hydraulic supports 7 in length, and the tail mark point d is generally arranged at a position which is away from the end tail f of the fully mechanized mining face by ten hydraulic supports in length. Taking a behavior example on the coal mining machine 4 (namely, coal mining travels from a point a at the end of the fully mechanized mining face to a point f at the end tail of the fully mechanized mining face): when the coal mining machine 4 starts to travel from the fully mechanized working face end point b to the fully mechanized working face end point f in the direction of the tail mark point d and then reaches the position point e with the direction changed for the first time, the travel track of the coal mining machine 4 is considered to be measured, namely, the travel profile curve between the point b and the point e is the complete travel track, the measurement process requires that the distance between the points ab is less than the distance between the points ac, and the distance between the points ef is less than the distance between the points df.

Step 2.2, splicing the traveling track segments of the coal mining machine: while mining coalWhen the measurement process of the machine walking encoder 6 is interrupted, the inertial navigation system 5 records the walking track of the coal mining machine again from the original point O, and at the moment, the walking track of the coal mining machine needs to be spliced, and the coordinate point (X) of the coal mining machine at the moment of interruption t is recorded_t,Y_t) Commanding all coal mining machine coordinate points recorded againRespectively associated with coordinate points (X)_t,Y_t) Adding to obtain a complete coal mining machine walking track measurement curve, wherein i is 1,2 and 3 … N;

step 2.3, coordinate point optimization:

step 2.3.1, dividing the generated coordinate points of the coal mining machine walking track measurement curve at equal intervals, setting the division interval L to be 0.5m, and dividing all the coordinate points (X) of the coal mining machine in each equal interval_l,Y_l) Arithmetic mean is performed to generate a coordinate point (X)_L,Y_L) Representing the coordinate points of the interval area, and skipping the interval area if the number of the generated coordinate points of the interval area is 0; and finally, the total number of points on the optimized coal mining machine walking track measurement curve is less than or equal to the total number of the interval areas.

Step 2.3.2, representing points (X) in all interval regions by a cubic spline interpolation method and natural boundary conditions_L,Y_L) Curve fitting is carried out to generate a preliminary contour line l 'of the coal mining machine walking curve'₀As shown in fig. 2.

Step 2.4, rotate the preliminary contour l'₀And (3) to a horizontal state: using the connecting line between the set head mark point c and the tail mark point d as the actual contour reference line l₀Extended to both sides, and the preliminary contour line l'₀By rotating the formula: x_R＝X_Tcos(β)+Y_Tsin(β)、Y_R＝Y_Tcos(β)-X_Tsin (β) is rotated to the horizontal direction, i.e. the actual profile reference line l₀Coincident with the X-axis, where the coordinate point (X)_R,Y_R) For the rotated shearer position coordinate point, (X)_T,Y_T) For the real-time shearer position coordinate point, β is the actual profile reference line l₀Angle with the X-axis, throughReference line l passing through actual contour₀Obtaining the slope of the slope by inverting; by means of₁Denotes the post-rotation reference line, < l >'₁Denotes the preliminary profile curve after rotation, l ″)₁Indicating the line of expected result after rotation, and the reference line l after rotation₁And automatically straightening the expected result line l' after rotation₁Are all in contact with X_TThe axes are parallel as shown in fig. 2.

Step 2.5, smoothing: adopting a quadratic exponential moving average algorithm to rotate the rotated preliminary profile curve l'₁Smoothing is carried out to obtain a profile curve l 'of the coal mining machine for calculating the correction amount RPC of each hydraulic support'₂As shown in fig. 3.

Step 2.6, setting the maximum frame moving distance D_maxAnd a minimum racking distance D_minSaid maximum racking distance D_maxThe maximum moving distance allowed by each hydraulic support when the hydraulic supports move the supports in the full range, and the minimum moving distance D_minThe minimum moving distance allowed by the hydraulic support; maximum racking distance D_maxGenerally equal to the depth of cut of the shearer drum.

Minimum racking distance D_minThe depth of the roller cannot be set to be too small or too large, and is generally half of the cutting depth of the roller of the coal mining machine. This is because if D is_minThe value is relatively small, such as D_minAnd (0), the straightening can be realized by the minimum number of cutters, but the influence on the propelling speed of the fully mechanized coal mining face is the largest, and the production progress is seriously influenced. If D is_minThe larger the value is, the more the number of knives to be straightened is, the longer the automatic straightening process is, and if D is_min＝D_maxIt is equivalent to turning off the automatic straightening function.

Step 2.7, setting the automatic alignment error d: calculating a coal mining machine walking profile curve l'₂The middle highest point A and the lowest point B are respectively connected with a reference line l after rotation₁Perpendicular distance d between_h、d_lAnd then:

setting d＝|d_h|+|d_lL, |; when d isWhen the diameter is less than or equal to 100mm, the self-alignment error is within the allowable range.

Step 3, calculating alignment parameters:

step 3.1, setting correction RPC: RPC maximum value of RPC_max0, minimum correction at minimum point B, RPC_Bmin＝D_min-D_maxThe correction amount at the maximum point A is RPC_A＝D_min-D_maxFor profile curve l'₂Setting the vertical distance D from any point M to the lowest point B_MAccording to the formula: RPC_M＝RPC_A×(D_M/D_max) I.e. a profile curve l 'can be calculated'₂Correction amount RPC of any M points_M。

Step 3.2, calculating the actual frame moving distance: according to all the reference lines l uniformly distributed after rotation₁The width and the spacing distance of the upper hydraulic supports 7, and the position of the midpoint of each hydraulic support 7 is determined to be in a profile curve l'₂Abscissa X of the coordinate system_kK is 1,2,3 … k, and k is the total number of the hydraulic supports 7; from the abscissa X_kThe vertical distance D from the midpoint of each hydraulic bracket 7 to the lowest point B can be calculated_kAnd further calculating to obtain the correction RPC of the midpoint of each hydraulic support 7_k(ii) a According to the calculated correction RPC_kFrom the formula: m is_k＝D_max+RPC_kAnd calculating to obtain the actual distance m of each hydraulic support 7 moving frame_k；

And 4, realizing automatic straightening of the fully mechanized coal mining face: actual distance m for moving hydraulic support 7 by gate main control computer 1_kAnd the hydraulic support is issued to the electro-hydraulic controller corresponding to the hydraulic support 7, and the electro-hydraulic controller controls the corresponding hydraulic support 7 to move according to the measuring range of the stroke sensor.

And recording the frame moving time of each hydraulic support 7 in the normal frame moving process, if a fault of a single stroke sensor occurs, in order to ensure the smooth frame moving, the hydraulic supports 7 move according to the time T, wherein T is the average value of the frame moving time of the left and right adjacent frames of the hydraulic supports 7.

Step 5, before the fully mechanized mining face is automatically straightened, firstly, the walking profile curve l 'of the coal mining machine 5 is subjected to'₂Performing a measurement, i.e. completing step 2, after which d is determinedWhether or not it is less than or equal to 100mm, if dIf the diameter is less than or equal to 100mm, continuing to measure and not correcting in the next mining cycle, and continuing to execute the step 2; if d is>1000m, executing the steps 3 to 5 in the next mining cycle to realize the automatic alignment of the fully mechanized coal mining face, and circulating the steps until d≤100mm。