Coal rock boundary bionic intelligent identification drill bit and coal rock boundary identification method

Abstract

The invention provides a coal rock boundary bionic intelligent recognition drill bit and a coal rock boundary recognition method. The coal rock boundary bionic intelligent recognition drill bit comprises a drill bit body, a vibration sensing array and a posture sensing module. Drill teeth are equidistantly distributed along a spiral line from the top to the tail end of the drill bit main body; the vibration sensing array comprises a plurality of piezoresistive accelerometers which are equidistantly distributed along a spiral line and mounted below the corresponding drill teeth; and the attitude sensing module adopts a double-gyroscope cooperative positioning architecture and is used for resolving the actual attitude of the drill bit and positioning the boundary of the coal rock. The high-frequency vibration signals of the drill teeth in contact with the coal rock are captured in real time through the spirally-distributed vibration sensing arrays, the three-dimensional dynamic contact model is constructed in combination with the spatial positioning data of the double-gyroscope attitude module, the coal rock boundary can be recognized in the coal mining process, non-coal-mine substances such as rock walls can be avoided in time, the net coal mining rate is increased, and the coal mining efficiency is improved. And attitude calculation of the drill bit and positioning of the coal rock boundary can be realized.

Description

Technical Field

[0001] The present application relates to the technical field of coal-rock boundary recognition, and in particular to a coal-rock boundary bionic intelligent recognition drill bit and a coal-rock boundary recognition method. Background Art

[0002] In the field of coal-rock boundary identification, automatic recognition technology of coal-rock interface is an important technology for realizing intelligent coal mining and is also the key to realizing unmanned comprehensive mining. However, due to the low recognition accuracy of traditional coal-rock interface recognition methods, the recovery rate of coal resources is reduced and the gangue content in coal is increased, which affects the development of the industrial economy.

[0003] In coal mining, accurate identification of the coal-rock interface has long faced a technical bottleneck. Traditional methods rely primarily on manual judgment or single-sensor detection, and their limitations are particularly pronounced in complex geological conditions. Manual judgment is subject to high subjectivity and delayed response, while sensors based on acoustic waves or resistivity are susceptible to underground dust, humidity, and electromagnetic interference, resulting in significant identification errors. This lack of precision directly contributes to an increased rate of gangue inclusion during the mining process, which not only reduces the calorific value of the coal but also increases the energy consumption burden of the washing process.

[0004] The dynamic complexity of the underground environment further amplifies the technical challenges. The physical properties of coal seams and surrounding rocks often exhibit gradual transition characteristics, and traditional threshold methods have difficulty capturing this nonlinear change in a timely manner. When the drill bit passes through the coal-rock interface, the vibration frequency will fluctuate continuously within a certain range, but the fixed threshold algorithm will misjudge the vibration signal in the transition zone as a single material category. This misjudgment causes the coal mining machine to frequently adjust the cutting trajectory, forming a jagged mining face and reducing the stability of the roof. In addition, problems such as uneven lighting and diffuse dust underground make it difficult for image recognition-based systems to operate stably. Conventional image processing algorithms have a high error rate under low-contrast conditions.

[0005] Existing technologies also have significant limitations in their ability to process multi-source data fusion. Furthermore, the spatial positioning accuracy of traditional methods is limited by the sensor layout, making omnidirectional sensing around the drill bit impossible, resulting in significant blind spots in boundary recognition. Detection technology based on high-pressure water jets requires large-scale water storage, making it difficult to scale in water-scarce mining areas. Furthermore, gamma ray detection poses radiation safety risks, limiting its scope of application.

[0006] From an industrial economic perspective, the ripple effects of identification errors cannot be ignored. Increased rates of gangue inclusion lead to increased costs for washing each ton of coal, which, based on annual production capacity, could result in annual losses of millions of yuan. More seriously, inaccurate interface identification can damage the roof and floor structures of coal seams, increase roadway support costs, and shorten the service life of mines. These factors collectively hinder the large-scale application of intelligent mining technologies and highlight the urgency of developing new identification technologies. Currently, breakthroughs in key technologies such as multi-source information fusion and anti-interference algorithm optimization are urgently needed to achieve accurate and dynamic identification of coal-rock interfaces. Summary of the Invention

[0007] The present application provides a coal-rock boundary bionic intelligent recognition drill bit, which can solve the technical problems of low precision, poor real-time performance and weak anti-interference ability of traditional coal-rock interface recognition methods in the prior art.

[0008] In a first aspect, the present application provides a coal-rock boundary bionic intelligent identification drill bit, comprising: The drill bit body has drill teeth evenly distributed along the spiral line from the top to the end; a vibration sensing array comprising a plurality of piezoresistive accelerometers, equidistantly distributed along the spiral line and mounted below the corresponding drill teeth; The attitude perception module adopts a dual-gyroscope collaborative positioning architecture to calculate the actual attitude of the drill bit and locate the coal-rock boundary.

[0009] Furthermore, the drill teeth are conical teeth.

[0010] Furthermore, the spiral line includes a plurality of spiral line segments connected in sequence, and the plurality of spiral line segments all run counterclockwise and have equal spiral pitch angles.

[0011] Furthermore, the vibration sensing array includes multiple piezoresistive accelerometers, wherein the piezoresistive accelerometer located at the top of the drill bit and the piezoresistive accelerometer closest to it are located in the vertical plane of the gyroscope, and the multiple piezoresistive accelerometers constitute a three-dimensional spatial vibration detection network of the drill bit.

[0012] Furthermore, at least two piezoresistive accelerometers coincide with a vertical plane of the gyroscope.

[0013] Furthermore, the dual-gyroscope cooperative positioning architecture includes two gyroscopes that cooperate with each other and are respectively installed at the drill bit axis position and the drilling rig base.

[0014] In a second aspect, the present application provides a coal-rock boundary recognition method, which uses the above-mentioned coal-rock boundary bionic intelligent recognition drill bit, including the following steps: The drill tooth vibration signal is collected in real time through a piezoresistive accelerometer. When the drill tooth vibration signal is out of the coal seam characteristic range, non-coal rock signal recognition is triggered. When non-coal rock signals are identified, the three-dimensional coordinates of the abnormal point are calculated based on the geometric relationship of the dual gyroscopes and the drill tooth height; The mine boundary model is generated by accumulating abnormal points.

[0015] Furthermore, when a non-coal rock signal is identified, the three-dimensional coordinates of the abnormal point are calculated based on the geometric relationship of the dual gyroscopes and the drill tooth height, which specifically includes the following steps: When the drill bit contacts non-coal minerals, based on the preset sensor spatial distribution and real-time vibration data, the drill tooth height compensation parameter is used to convert the abnormal vibration signal into a three-dimensional relative coordinate in the local coordinate system to obtain the relative coordinates of the vibration source; Based on the real-time rotation angle of the drill arm, the spatial correlation between the gyroscopes at the drill head and the base is established through a dynamic geometric solution model to obtain the absolute coordinates of the drill head gyroscope. The relative coordinates of the spatial superposition vibration source are spatially superimposed with the absolute position of the base gyroscope, and the three-dimensional coordinates of the abnormal point are finally output.

[0016] Furthermore, based on the real-time rotation angle of the drill arm, the spatial association between the gyroscopes at the drill bit end and the base end is established through a dynamic geometric solution model to obtain the absolute coordinates of the drill bit gyroscope, which specifically includes the following steps: Based on the real-time rotation angle of the drill arm, the spatial correlation between the gyroscopes at the drill head and the base under different working conditions is established through a dynamic geometric solution model: The absolute coordinates of the drill bit gyroscope are obtained by solving the spatial correlation relationship in real time.

[0017] Furthermore, the obtaining of the absolute coordinates of the drill bit gyroscope by real-time solving the spatial correlation relationship specifically includes the following steps: Use the magnetometer to calibrate the absolute coordinates of the base gyroscope and establish the reference point of the geodetic coordinate system; The rotation angle of the drill arm is collected in real time, and the solution model in the corresponding spatial relationship is selected according to the working conditions to obtain the dynamic spacing: Matrix operations are performed on the dynamic spacing obtained by solution and the absolute coordinates of the base gyroscope. The solution frequency is dynamically adjusted according to the drill bit speed. The gyroscope drift error is eliminated through the Kalman filter algorithm, and the absolute coordinates of the drill bit gyroscope are finally output.

[0018] The beneficial effects of the technical solutions provided in the embodiments of the present application include at least: The high-frequency vibration signals of the contact between the drill teeth and the coal rock are captured in real time through a spirally distributed vibration sensing array. Combined with the spatial positioning data of the dual-gyroscope attitude module, a three-dimensional dynamic contact model is constructed, which realizes real-time response and high-precision positioning of the coal-rock interface identification, timely avoids non-coal minerals such as rock walls, improves the net coal mining rate, and can realize the attitude solution of the drill bit and locate the coal-rock boundary. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0020] Figure 1 This is a schematic diagram of the drilling rig structure and underground soil layers; Figure 2 This is a diagram showing the distribution pattern of scorpion vibration sensors in a one-dimensional plane; Figure 3 Schematic diagram of the piezoresistive accelerometer and drill tooth distribution provided in the embodiment of the present application; Figure 4 This is a diagram showing the installation arrangement of the drill teeth and sensors on the drill bit provided in an embodiment of the present application; Figure 5 A flowchart of the working principle provided for the embodiment of this application; Figure 6 A schematic diagram of a non-coal mineral substance sensed by piezoresistive accelerometer No. 3 at a certain moment provided in an embodiment of the present application; Figure 7 Amplitude variation diagram of piezoresistive accelerometer No. 3 provided in the embodiment of the present application; Figure 8 A schematic diagram of the positional relationship between the gyroscope and the piezoresistive accelerometer provided in an embodiment of the present application; Figure 9 A schematic diagram of a drilling rig arm in a horizontal position provided in an embodiment of the present application; Figure 10 The embodiment of the present application provides a schematic diagram of a drill arm rotating upward by an angle β; Figure 11 The embodiment of the present application provides a schematic diagram of the drill arm rotating downward by an angle β.

[0021] In the figure: 1 is the roof; 2 is the drill bit; 3 is the drill arm; 4 is the cockpit; 5 is the fuselage; 6 is the gangue; 7 is the coal; 8 is the coal mining plate; 9 is the bottom plate; 10 is the crawler track; 11 is the coal mine discharge device; 21 is the drill tooth; 22 is the piezoresistive accelerometer; 23 is the gyroscope. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0023] Drilling rig structure and underground soil Figure 1 As shown, the drilling rig consists of a drill bit 2, a drill arm 3, a cab 4, a body 5, a mining plate 8, tracks 10, and a coal extraction device 11. The drill rig excavates unmined coal 7 between the roof 1, floor 9, and waste rock 6. During the mining process, the drill bit's vibration frequency is primarily concentrated between 0 and 800 Hz. The vibration acceleration of the drill teeth impacting the hard rock is typically in the range of 200–800 g. The temperature of the drill teeth is typically around 20°C–30°C, and the tooth sleeve diameter is generally 30–40 mm.

[0024] like Figure 2 As shown in the figure, the vibration sensors used by scorpions to sense vibrations are located at the metatarsal joints of the end metatarsals of their eight legs. When a scorpion ambushes its prey in a one-dimensional plane, its four pairs of legs are symmetrically distributed on both sides of its body. The eight legs form a circle with a diameter of z cm, that is, the eight vibration sensors form a circle with a diameter of z cm. The scorpion's forward direction is defined as 0°, and the distribution angles of the vibration sensors are approximately γ1, γ2, γ3, γ4, -γ1, -γ2, -γ3, and -γ4, respectively.

[0025] Scorpions' vibration sensing relies primarily on vibration sensors on their legs. Each sensor has 12 curved slits arranged in a fan-shaped pattern, sensing vibration stimuli through the strain of the slit structure. Piezoresistive accelerometers, which operate on a similar principle, work by elastically deforming an elastic beam when vibration is sensed, causing the resistance of the piezoresistor to change, thereby sensing vibration. Existing piezoresistive accelerometers on the market have a range of 2000g, can withstand temperatures of 121 degrees Celsius, and come in sizes of 4.8×11.9mm and 9×7.5mm, which are suitable for practical installation and application scenarios. Therefore, piezoresistive accelerometers were selected as the sensor for the drill's vibration sensing.

[0026] Based on the distribution array of vibration sensors at the metatarsal joints at the end of the scorpion's eight walking legs in a one-dimensional plane, this application stretches the distribution array of the scorpion's vibration sensors in the one-dimensional plane into the drill bit in three-dimensional space, designs the arrangement array of the drill bit vibration sensors, and considers the protection of the piezoresistive accelerometer and more effective perception of vibration. The drill bit vibration sensors are installed under the drill teeth according to the arrangement array, and a gyroscope is installed inside the drill bit to solve the relative posture of the drill bit and relatively locate the coal-rock boundary.

[0027] like Figure 3 As shown, the present application provides a coal-rock boundary bionic intelligent identification drill bit, including a drill bit body, a vibration sensing array and a posture sensing module; drill teeth 21 are equidistantly distributed on a spiral line from the top of the drill bit to the end of the drill bit; the vibration sensing array includes a plurality of piezoresistive accelerometers 22, which are equidistantly distributed along the spiral line and installed under the corresponding drill teeth; the posture sensing module adopts a dual-gyroscope collaborative positioning architecture for solving the actual posture of the drill bit and locating the coal-rock boundary.

[0028] This embodiment uses a spirally distributed vibration sensing array to capture the high-frequency vibration signals of the contact between the drill teeth and the coal rock in real time, and combines the spatial positioning data of the dual gyroscope attitude module to construct a three-dimensional dynamic contact model, thereby achieving real-time response and high-precision positioning of the coal-rock interface identification.

[0029] In one embodiment, the drill teeth are conical teeth, which can maintain a relatively stable structural state during the cutting process, have evenly distributed wear, and have strong penetrating power.

[0030] In one embodiment, the spiral line includes a plurality of spiral segments connected in sequence, and the plurality of spiral segments all run counterclockwise and have equal spiral angles; specifically, Figure 3 As shown, the number of spiral segments is 3, the drill teeth on the drill bit are distributed in three counterclockwise spiral lines, the rise angles of the three spiral lines are all α, and the number of drill teeth is n, which are equidistantly distributed on the spiral lines; specifically, the drill teeth on the drill bit are distributed in three counterclockwise spiral lines, the rise angles of the three spiral lines are all α; the number of drill teeth is n, which are equidistantly distributed on the spiral lines.

[0031] In one embodiment, the vibration sensing array includes a plurality of piezoresistive accelerometers, wherein the piezoresistive accelerometer located at the top of the drill bit and the piezoresistive accelerometer closest thereto are located in a plane perpendicular to the gyroscope, and the plurality of piezoresistive accelerometers constitute a three-dimensional vibration detection network of the drill bit; specifically, the piezoresistive accelerometer is a piezoresistive accelerometer; Figure 3This is a schematic diagram of the distribution of piezoresistive accelerometers and drill teeth. The drill teeth are installed on the drill bit in a spiral arrangement, which makes it easier for the drill bit to drill into the coal layer. The spiral arrangement allows the cutters to contact the rock and soil in stages during rotation, preventing all cutters from impacting the formation at the same time, reducing instantaneous load fluctuations, and protecting the drive system. Specifically, the number of piezoresistive accelerometers is 5, and 5 piezoresistive accelerometers are used. Since the drill bit rotates at a speed of 30-50 r / min during operation, piezoresistive accelerometers No. 1-5 are installed equidistantly below the drill teeth along the spiral line with the No. 1 piezoresistive accelerometer at the top of the drill bit as a reference. This can detect vibrations around the drill bit in all directions, saving costs.

[0032] In one embodiment, the dual-gyroscope collaborative positioning architecture includes two gyroscopes that work together, including a drill axis gyroscope and a base gyroscope; the drill axis gyroscope is directly mounted on the drill bit's rotating shaft to monitor the drill bit's angular velocity and attitude changes in real time, especially dynamic deflection during drilling; the base gyroscope is fixed to the drill rig base to provide a global reference benchmark for eliminating interference with positioning caused by the overall movement of the drill rig (such as drill rig vibration and ground subsidence), and separating local and global errors by comparing data with that of the drill bit gyroscope.

[0033] Figure 4 For the installation arrangement of the drill teeth and sensors on the drill bit, a piezoresistive accelerometer is installed under the drill teeth to sense the vibration frequency of the drill teeth. Different vibration frequencies are used to distinguish whether the drilling is in a coal mine or a non-coal mine at a certain moment. If the frequency sensed at a certain moment exceeds the maximum vibration frequency of the coal mine or is less than the minimum vibration frequency of the coal mine, it is determined that the drilling is in a non-coal mine at this moment, thereby realizing the coal-rock boundary identification and improving the coal mining rate. The gyroscope 23 is installed inside the drill bit to solve the relative posture of the drill bit and the relative positioning of the coal-rock boundary.

[0034] In one embodiment, at least two piezoresistive accelerometers are aligned with the vertical plane of the gyroscope. Specifically, during the design process, the mounting positions of piezoresistive accelerometers No. 1 and No. 2 are aligned with the yz plane of the gyroscope, and the horizontal axis of the drill arm is aligned with the y-axis of the gyroscope. The drill head's initial position is defined as when piezoresistive accelerometer No. 2 is located above the vertical plane of the drill bit, the drill bit is rotated to the front relative to the drill rig, and the drill arm is in a horizontal position.

[0035] In a second aspect, the present application provides a coal-rock boundary recognition method, which uses the above-mentioned coal-rock boundary bionic intelligent recognition drill bit, including the following steps: Step S1: using a piezoresistive accelerometer to collect drill tooth vibration signals in real time, and triggering non-coal rock signal recognition when the drill tooth vibration signals are not within the coal seam characteristic range; Step S2: When a non-coal rock signal is identified, the three-dimensional coordinates of the abnormal point are calculated based on the geometric relationship of the dual gyroscopes and the drill tooth height; Step S3: Accumulate abnormal points to generate a mine boundary model, and dynamically adjust the drilling path based on the drill arm motion parameters to avoid non-coal and rock areas.

[0036] In one embodiment, step S2: when a non-coal rock signal is identified, the three-dimensional coordinates of the abnormal point are calculated based on the geometric relationship of the dual gyroscopes and the drill tooth height, specifically including the following steps: Step S21: When the drill bit contacts non-coal minerals, based on the preset sensor spatial distribution and real-time vibration data, the abnormal vibration signal is converted into three-dimensional relative coordinates in the local coordinate system using the drill tooth height compensation parameter to obtain the relative coordinates of the vibration source; Step S22: Based on the real-time rotation angle of the drill arm, a spatial correlation between the gyroscopes at the drill head end and the base end is established through a dynamic geometric solution model to obtain the absolute coordinates of the drill head gyroscope; Step S23: The relative coordinates of the spatial superposition vibration source and the absolute position of the base gyroscope are spatially superimposed, and the three-dimensional coordinates of the abnormal point are finally output.

[0037] During the coal mining process, the drill bit directly drills into the coal seam, but the drill bit cannot identify whether it is currently drilling into a coal mine or a non-coal mine. Therefore, a piezoresistive accelerometer is installed under the drill teeth of the drill bit. By sensing the vibration frequency, it can be used to identify whether the current drilling is into a coal mine or a non-coal mine, thereby realizing coal-rock boundary recognition and deciding whether to continue drilling or change direction in the next moment.

[0038] The specific working principle is as follows Figure 5 As shown, at a certain moment, the drill bit is drilling into the coal mining position, which is directly contacted by the drill teeth. The piezoresistive accelerometer under the drill teeth senses the vibration frequency of the position at this moment. If the vibration amplitude of the position at this moment is within the vibration change range of the coal mine, it means that the drill is currently drilling into a coal mine and continues to drill in the current direction; if the vibration amplitude of the position at this moment is not within the vibration change range of the coal mine, it means that the drill is currently drilling into a non-coal mine. If the vibration amplitude of the piezoresistive accelerometer at this moment exceeds the upper limit of the vibration amplitude of drilling into a coal mine, it means that the drill bit is drilling into a non-coal mineral material with a harderness greater than that of a coal mine. If the vibration amplitude of the piezoresistive accelerometer at this moment is lower than the lower limit of the vibration amplitude of drilling into a coal mine, it means that the drill bit is drilling into a non-coal mineral material with a harderness less than that of a coal mine. Since the drill is drilling into a non-coal mine, the alarm sounds and the drilling direction needs to be changed.

[0039] Take the No. 3 piezoresistive accelerometer as an example. Figure 6 As shown in Figure 3, when drilling into non-coal minerals at a certain moment, and at this moment it happens to be in direct contact with the drill teeth above the No. 3 piezoresistive accelerometer, the vibration amplitude of the No. 3 piezoresistive accelerometer will change significantly; Figure 7As shown, if the drill bit is drilling into a non-coal mineral substance with a harderness greater than that of the coal mine, the vibration amplitude of the No. 3 piezoresistive accelerometer will exceed the upper limit of the vibration amplitude when drilling into the coal mine. If the drill bit is drilling into a non-coal mineral substance with a harderness less than that of the coal mine, the vibration amplitude of the No. 3 piezoresistive accelerometer will be lower than the lower limit of the vibration amplitude when drilling into the coal mine. In one embodiment, step S21: when the drill bit contacts non-coal minerals, based on the preset sensor spatial distribution and real-time vibration data, the abnormal vibration signal is converted into three-dimensional relative coordinates in the local coordinate system using the drill tooth height compensation parameter to obtain the relative coordinates of the vibration source; specifically, this is achieved as follows: Figure 8 Figure 3 is a schematic diagram of the positional relationship between the gyroscope and the piezoresistive accelerometer. The gyroscope is installed on the axis of the drill bit so that the yz plane of piezoresistive accelerometers No. 1 and No. 2 coincides with the gyroscope. Based on the geometric relationship between the drill bit and the gyroscope, the straight-line distances from piezoresistive accelerometers No. 1-5 to the gyroscope are calculated as a, b, c, d, and e, respectively.

[0040] Step S211: When the drill bit is in the initial position, the attitudes (pitch angle, roll angle, yaw angle) of piezoresistive accelerometers 1-5 relative to the gyroscope are calculated, which are (0, 0, 0), (θ2, 0, 0), (θ3, φ3, ψ3), (θ4, φ4, ψ4), and (θ5, φ5, ψ5), respectively.

[0041] Step S212: When the drill rig starts working, the drill head changes its posture from the initial position. The gyroscope installed on the drill head senses the drill head's posture. When the drill head's posture at a certain moment is (θ, φ, ψ), the positions of the five piezoresistive accelerometers relative to the gyroscope can be calculated: The attitude of piezoresistive accelerometer No. 1: ; ; ; The attitude of piezoresistive accelerometer No. 2: ; ; ; The attitude of the No. 3 piezoresistive accelerometer: ; ; ; The attitude of the No. 4 piezoresistive accelerometer: ; ; ; The attitude of the No. 5 piezoresistive accelerometer: ; ; ; Step S213: Given the current postures and linear distances of the five piezoresistive accelerometers relative to the gyroscope, the positions of the five piezoresistive accelerometers relative to the gyroscope can be calculated. Also, given the overall height f of the drill tooth, the position of the vibration source relative to the gyroscope can be calculated.

[0042] The coordinates of the gyroscope inside the drill bit are (x, y, z) = (x0, y0, z0), where θ is positive when it is an elevation angle and negative when it is a depression angle; ψ is positive when it rotates counterclockwise around the z axis and negative when it rotates clockwise; Coordinates of piezoresistive accelerometer No. 1: x1=x0+a·cos(θ)·sin(ψ); y1=y0+a·cos(θ)·cos(ψ); z1=z0+a·sin(θ); Coordinates of the vibration source sensed by piezoresistive accelerometer No. 1: x1=x0+a·cos(θ)·sin(ψ); y1=y0+a·cos(θ)·cos(ψ); z1=z0+a·sin(θ)+f; Coordinates of piezoresistive accelerometer No. 2: x2=x0+b·cos(θ+θ2)·sin(ψ); y2=y0+b·cos(θ+θ2)·cos(ψ); z2=z0+b·sin(θ+θ2); Coordinates of the vibration source sensed by piezoresistive accelerometer No. 2: x2=x0+b·cos(θ+θ2)·sin(ψ); y2=y0+b·cos(θ+θ2)·cos(ψ); z2=z0+b·sin(θ+θ2)+f; Coordinates of piezoresistive accelerometer No. 3: x3=x0+c·cos(θ+θ3)·sin(ψ+ψ3); y3=y0+c·cos(θ+θ3)·cos(ψ+ψ3); z3=z0+c·sin(θ+θ3); Coordinates of the vibration source sensed by piezoresistive accelerometer No. 3: x3=x0+c·cos(θ+θ3)·sin(ψ+ψ3); y3=y0+c·cos(θ+θ3)·cos(ψ+ψ3); z3=z0+c·sin(θ+θ3)+f; Coordinates of piezoresistive accelerometer No. 4: x4=x0+d·cos(θ+θ4)·sin(ψ+ψ4); y4=y0+d·cos(θ+θ4)·cos(ψ+ψ4); z4=z0+d·sin(θ+θ4); Coordinates of the vibration source sensed by piezoresistive accelerometer No. 4: x4=x0+d·cos(θ+θ4)·sin(ψ+ψ4); y4=y0+d·cos(θ+θ4)·cos(ψ+ψ4); z4=z0+d·sin(θ+θ4)+f; Coordinates of piezoresistive accelerometer No. 5: x5=x0+e·cos(θ+θ5)·sin(ψ+ψ5); y5=y0+e·cos(θ+θ5)·cos(ψ+ψ5); z5=z0+e·sin(θ+θ5); Coordinates of the vibration source sensed by piezoresistive accelerometer No. 5: x5=x0+e·cos(θ+θ5)·sin(ψ+ψ5); y5=y0+e·cos(θ+θ5)·cos(ψ+ψ5); z5=z0+e·sin(θ+θ5)+f.

[0043] In one embodiment, step S22: establishing a spatial association between the gyroscopes at the drill bit end and the base end through a dynamic geometric solution model based on the real-time rotation angle of the drill arm, and obtaining the absolute coordinates of the drill bit gyroscope, specifically includes the following steps: Based on the real-time rotation angle of the drill arm, the spatial correlation between the gyroscopes at the drill head and the base under different working conditions is established through a dynamic geometric solution model: (1) If Figure 9 Schematic diagram of the drill arm in a horizontal position. Based on the geometric relationship, the distance between the two gyroscopes when the drill arm is in a horizontal position can be calculated. : ; 1 is the gyroscope mounted on the drill bit; 2 is the gyroscope and accelerometer mounted on the base; A is the connection point between the articulated support and the drill arm; g is the distance between the articulated support and the gyroscope on the drill bit; h is the height of the articulated support; β0 is the vertical angle between the two gyroscopes; x, y, and z are the three axes of the gyroscope and accelerometer; (2) If Figure 10 Schematic diagram of the drill arm rotating upward at an angle of β. Based on the geometric relationship, the distance between the two gyroscopes can be calculated when the drill arm rotates upward at an angle of β. :

[0044] A is the connection point between the articulated support and the drill arm; β0-β is the vertical angle between the two gyroscopes; x, y, and z are the three axes of the gyroscope and accelerometer; β is the upward rotation angle of the drill arm Figure 10 Schematic diagram of the drill arm rotating upward at an angle of β (3) If Figure 11 Schematic diagram of the drill arm rotating downward at an angle of β. Based on the geometric relationship, the distance between the two gyroscopes can be calculated when the drill arm rotates downward at an angle of β. :

[0045] The absolute coordinates of the drill bit gyroscope are obtained by solving the spatial correlation relationship in real time; further, the method specifically includes the following steps: Use the magnetometer to calibrate the absolute coordinates of the base gyroscope and establish the reference point of the geodetic coordinate system; The rotation angle of the drill arm is collected in real time, and the solution model in the corresponding spatial relationship is selected according to the working conditions to obtain the dynamic spacing: Matrix operations are performed on the dynamic spacing obtained by solution and the absolute coordinates of the base gyroscope. The solution frequency is dynamically adjusted according to the drill bit speed. The gyroscope drift error is eliminated through the Kalman filter algorithm, and the absolute coordinates of the drill bit gyroscope are finally output.

[0046] In one embodiment, step S3: accumulating abnormal points to generate a mine tunnel boundary model, and dynamically adjusting the drilling path to avoid non-coal rock areas in combination with drill arm motion parameters.

[0047] The distance L between the two gyroscopes when the drill arm is in different positions and the actual position of the drill rig obtained by the gyroscope and accelerometer are known. At the same time, the relative position of the vibration source relative to the gyroscope on the drill bit is known. Based on the connection between the two gyroscopes, the actual attitude of the drill bit and the location of the coal-rock boundary can be calculated. When the drill bit is drilling into a non-coal mine, the gyroscope installed on the drill bit and the gyroscope and accelerometer installed on the base can perform attitude calculation, locate the vibration point at the current moment, and save the position of the non-coal mine at the current moment. By weaving together the recorded location points, an underground mine network can be drawn, which is convenient for subsequent mine planning and disaster warning. In the description of this application, it should be noted that the terms "upper" and "lower" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. Unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0048] It should be noted that, in this application, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.

[0049] The foregoing is merely a list of specific embodiments of the present application, intended to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the broadest scope consistent with the principles and novel features of the present application.

Claims

1. A coal-rock boundary bionic intelligent identification drill bit, characterized in that: include: The drill bit body has drill teeth evenly distributed along the spiral line from the top to the end; a vibration sensing array comprising a plurality of piezoresistive accelerometers, equidistantly distributed along the spiral line and mounted below the corresponding drill teeth; The attitude perception module adopts a dual-gyroscope collaborative positioning architecture to calculate the actual attitude of the drill bit and locate the coal-rock boundary.

2. The coal-rock boundary bionic intelligent identification drill bit according to claim 1, characterized in that: The drill teeth are conical teeth.

3. The coal-rock boundary bionic intelligent identification drill bit according to claim 1, characterized in that: The spiral line includes a plurality of spiral line segments connected in sequence, and the plurality of spiral line segments all run counterclockwise and have the same spiral pitch angle.

4. The coal-rock boundary bionic intelligent identification drill bit according to claim 1, characterized in that: The vibration sensing array includes multiple piezoresistive accelerometers, wherein the piezoresistive accelerometer located at the top of the drill bit and the piezoresistive accelerometer closest to it are located in the vertical plane of the gyroscope. The multiple piezoresistive accelerometers constitute a three-dimensional vibration detection network of the drill bit.

5. The coal-rock boundary bionic intelligent identification drill bit according to claim 1, characterized in that: At least two piezoresistive accelerometers are coincident with the vertical plane of the gyroscope.

6. The coal-rock boundary bionic intelligent identification drill bit according to claim 1, characterized in that: The dual-gyroscope cooperative positioning architecture includes two gyroscopes that cooperate with each other and are respectively installed at the drill bit axis position and the drilling rig base.

7. A coal-rock boundary recognition method, using the coal-rock boundary bionic intelligent recognition drill bit according to any one of claims 1 to 6, characterized in that The following steps are involved: The drill tooth vibration signal is collected in real time through a piezoresistive accelerometer. When the drill tooth vibration signal is out of the coal seam characteristic range, non-coal rock signal recognition is triggered. When non-coal rock signals are identified, the three-dimensional coordinates of the abnormal point are calculated based on the geometric relationship of the dual gyroscopes and the drill tooth height; The mine boundary model is generated by accumulating abnormal points.

8. The coal-rock boundary recognition method according to claim 7, characterized in that: When a non-coal rock signal is identified, the three-dimensional coordinates of the abnormal point are calculated based on the geometric relationship of the dual gyroscopes and the drill tooth height, which specifically includes the following steps: When the drill bit contacts non-coal minerals, based on the preset sensor spatial distribution and real-time vibration data, the drill tooth height compensation parameter is used to convert the abnormal vibration signal into a three-dimensional relative coordinate in the local coordinate system to obtain the relative coordinates of the vibration source; Based on the real-time rotation angle of the drill arm, the spatial correlation between the gyroscopes at the drill head and the base is established through a dynamic geometric solution model to obtain the absolute coordinates of the drill head gyroscope. The relative coordinates of the spatial superposition vibration source are spatially superimposed with the absolute position of the base gyroscope, and the three-dimensional coordinates of the abnormal point are finally output.

9. The coal-rock boundary recognition method according to claim 8, characterized in that: The method of establishing a spatial association between the gyroscopes at the drill bit end and the base end based on the real-time rotation angle of the drill arm through a dynamic geometric solution model to obtain the absolute coordinates of the drill bit gyroscope specifically includes the following steps: Based on the real-time rotation angle of the drill arm, the spatial correlation between the gyroscopes at the drill head and the base under different working conditions is established through a dynamic geometric solution model: The absolute coordinates of the drill bit gyroscope are obtained by solving the spatial correlation relationship in real time.

10. The coal-rock boundary recognition method according to claim 9, characterized in that: The step of obtaining the absolute coordinates of the drill bit gyroscope by solving the spatial correlation relationship in real time specifically includes the following steps: Use the magnetometer to calibrate the absolute coordinates of the base gyroscope and establish the reference point of the geodetic coordinate system; The rotation angle of the drill arm is collected in real time, and the solution model in the corresponding spatial relationship is selected according to the working conditions to obtain the dynamic spacing: The dynamic spacing obtained by the solution and the absolute coordinates of the base gyroscope are subjected to matrix operation. The solution frequency is dynamically adjusted according to the drill bit speed. The gyroscope drift error is eliminated through the Kalman filter algorithm, and the absolute coordinates of the drill bit gyroscope are output.

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