A laser ranging and pressure average fusion drilling pipe counting method

Abstract

The present application belongs to the technical field of automatic detection, and discloses a kind of laser ranging and pressure mean fusion's drill pipe counting method, for the single laser ranging drill pipe counting of existing single laser ranging drill pipe counting in coal mine underground high dust, strong vibration, high humidity environment, prone to data distortion, no physical calibration means, low fault tolerance problem, the present application is arranged multiple pressure sensors in the drill pipe limiting groove bottom, using original fixed hole installation, without changing mechanical structure;With laser ranging to collect drill pipe stacking height and convert initial number as main, with groove bottom multi-point pressure mean to convert pressure count number as auxiliary, through two-dimensional data grading cross-checking to realize accurate counting;When laser fails, with pressure data to bottom, when pressure is close to zero, veto laser false data;And have drill pipe stacking posture detection and dynamic self-calibration capability, greatly improve the precision, anti-interference ability and fault tolerance of multilayer stacked drill pipe counting, adapt to complex working conditions in mine.

Description

Technical Field

[0001] The present invention belongs to the technical field of automatic detection, and relates to a drill pipe counting method fusing laser ranging and pressure mean value. Background Art

[0002] In the intelligent drilling operation in underground coal mines, the drill pipe box matched with the automatic drilling rig is the core material storage mechanism for realizing continuous automatic operation. The drill pipe box usually adopts a limit slot grid structure, and a plurality of drill pipes can be stacked and stored in each slot position. To ensure that the manipulator can accurately and reliably automatically grab and replace drill pipes, it is necessary to count the remaining number of drill pipes in each limit slot accurately and in real time. This is a key prerequisite for avoiding faults such as empty grabbing of the manipulator, wrong grabbing quantity, and disordered rod changing sequence, and ensuring the continuous and stable operation of the drilling rig.

[0003] At present, the mainstream scheme for drill pipe counting of drill pipe boxes in the industry is single laser ranging scanning counting. This method detects the total height of the stacked drill pipes in a single limit slot through a laser sensor, and then converts the number of drill pipes through the ratio of the height to the standard thickness of a single drill pipe. This scheme has a simple principle, but has inherent defects and is difficult to meet the requirements of complex working conditions in underground coal mines.

[0004] First, the underground coal mine has a harsh environment with the characteristics of high dust, strong vibration and heavy moisture. In this environment, the lens of the laser sensor is very prone to dust accumulation and fogging, and the laser beam is prone to scattering and severe attenuation. This directly leads to jump and distortion of the laser ranging data, and the collected stacking height is unreliable. Secondly, unavoidable slight wear, local rust of drill pipes during use, and tiny gaps caused by stacking will lead to deviation between the actual equivalent thickness and the theoretical standard thickness of the drill pipes. Relying only on a single height data for conversion is very prone to errors of missing counting, undercounting or overcounting. The single laser counting scheme has low fault tolerance and reliability. Once a counting error occurs, it will cause a series of cascading faults in the subsequent manipulator drill pipe grabbing operation, which seriously affects the efficiency and stability of the continuous automatic operation of the drilling rig.

[0005] Therefore, there is an urgent need for a drill pipe counting method with strong anti-interference capability, self-inspection and error correction capabilities, so as to overcome the shortcomings of the existing single laser detection technology, adapt to the complex and harsh underground operation environment, and realize accurate and reliable counting of multi-layer stacked drill pipes. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to solve the above problems and provide a drill pipe counting method fusing laser ranging and pressure mean value.

[0007] To achieve the above purpose, the present invention provides the following technical solutions: A drill pipe counting method fusing laser ranging and pressure mean value, comprising the following steps: S1. Multiple pressure sensors are installed at the bottom of the drill rod limiting groove to collect the pressure load signal of the drill rod in the groove; at the same time, a laser rangefinder is used to collect the total height signal of the drill rod stack in the groove. S2. Based on the total height signal and combined with the pre-stored standard thickness of a single drill rod, the number of laser counts is calculated. S3. Based on the pressure load signals of the multiple pressure sensors, calculate the average pressure value, and combine it with the pre-stored single-rod reference pressure load to calculate the number of pressure counts. S4. Compare and verify the number of laser counts with the number of pressure counts, and determine the final number of drill rods according to the preset verification rules.

[0008] Furthermore, in step S1, the signals from the laser rangefinder and multiple pressure sensors are all connected to the existing electrical control controller of the drilling rig, and the electrical control controller realizes synchronous data acquisition, fusion calculation and verification and error correction.

[0009] Furthermore, in step S1, the total height signal acquisition of the laser rangefinder sensor and the weight load signal acquisition of multiple pressure sensors are performed simultaneously.

[0010] Furthermore, in step S1, the laser rangefinder is mounted on the drilling rig's robotic arm, which drives the scanning of the target limiting groove at a constant speed to collect the total height of the drill rod stack within the groove.

[0011] Furthermore, the plurality of pressure sensors consists of three, which are respectively arranged at the front, middle and rear ends of the bottom of the drill rod limiting groove. They are used to calculate the average pressure at three points to eliminate detection errors caused by drill rod stacking eccentricity and uneven local force.

[0012] Furthermore, the pressure sensor is a flat diaphragm explosion-proof pressure sensor, with its diaphragm installed flush with the bottom plane of the tank; the bottom of the tank is provided with an annular slag discharge trough to prevent coal slag from accumulating on the surface of the sensor diaphragm.

[0013] Furthermore, the multiple pressure sensors are installed and fixed through the original fixing holes at the bottom of the drill rod limiting groove, without changing the original mechanical structure of the drill rod limiting groove, and without affecting the stacking and picking up / dropping of the drill rod.

[0014] Furthermore, the method also includes a parameter pre-calibration step performed before the operation, specifically including: Geometric parameter calibration: Enter the standard single-layer thickness of a single-specification drill pipe, the maximum number of stacked layers in a single limiting groove, and the reference height of the empty groove; Load parameter calibration: The zero-point pressure value of each pressure sensor is calibrated under no-load conditions, and the pressure value under the corresponding conditions is collected by placing different numbers of drill rods respectively, and a pressure-number mapping table is established. Error threshold calibration: preset laser height deviation threshold, pressure average deviation threshold and dual data fault tolerance verification threshold.

[0015] Furthermore, the method for establishing the pressure-number mapping table is as follows: place 1, 2, and 3 drill rods to the full layer, collect the pressure values ​​of three pressure sensors under each quantity condition, calculate the average value, and form a correspondence between the average pressure value and the number of drill rods.

[0016] Furthermore, in step S2, the formula for calculating the number of laser beams is: initial number of laser beams = total stacking height ÷ standard thickness of a single beam.

[0017] Furthermore, in step S3, before calculating the average pressure value, the instantaneous fluctuation extreme values ​​of each pressure sensor signal are first eliminated; the formula for calculating the number of pressure counts is: number of pressure counts = average pressure value ÷ single rod reference pressure load.

[0018] Furthermore, the verification rules in step S4 include: When the difference between the laser count and the pressure count is within the preset fault tolerance threshold, both sets of data are deemed valid. The laser count result is used as the final drill rod quantity, and the pressure data is used as the filing verification data. When the number of laser counts is abnormal while the number of pressure counts detects a stable effective load signal, the laser detection is determined to be faulty. The pressure count is used as the final count result, and the laser sensor is marked as abnormal, triggering a mild warning. When the laser counting count indicates the presence of a drill rod while the pressure counting count is close to the zero point under no load, the laser detection is deemed to be generating false data, the laser counting result is rejected, and the slot is determined to be empty.

[0019] Furthermore, the specific conditions for determining laser detection failure are: the number of laser counts is too small or empty, and the load signal detected by the average pressure value stably and continuously exceeds the preset minimum effective load threshold.

[0020] Furthermore, when there are three pressure sensors, the verification rule also includes: judging whether the drill pipe stacking is abnormal by comparing the pressure distribution deviation between the readings of the three pressure sensors and the average pressure value; if the pressure deviation at any point exceeds the preset abnormal threshold, it is determined that the drill pipe stacking is not correct and the robot arm cannot directly grasp it.

[0021] Furthermore, the method also includes a dynamic self-calibration step: every set number of valid count samples, samples with the same number of laser count roots and pressure count roots are automatically selected, the average pressure and average thickness of a single rod are recalculated, and the pre-stored single rod reference pressure load and single rod standard thickness are updated in a progressive fine-tuning manner.

[0022] Furthermore, in the dynamic self-calibration step, the effective number of count samples is set to 80.

[0023] Furthermore, while triggering the mild warning, the system records abnormal information of the laser sensor to help determine whether the laser sensor has lens dust accumulation, beam scattering, or sensor malfunction.

[0024] The beneficial effects of this invention are as follows: 1. Dual-dimensional physical fusion verification fundamentally improves counting reliability. The core technical contribution of this invention lies in breaking through the dimensional limitations of traditional single-laser geometric detection, creatively integrating optical geometric dimension measurement (laser ranging) with rigid physical load measurement (average pressure at the bottom of the trench). Laser ranging reflects the "external height" information of the drill pipe stack, while pressure measurement reflects the "actual weight" information of the drill pipe stack. These two methods, based on completely different physical principles, independently characterize the same object (the number of drill pipes in the trench). This cross-verification mechanism between these two data sources allows the system to verify and provide a backup in case of anomalies in either dimension, fundamentally solving the industry pain point of "no self-checking, no error correction" in single-dimensional detection, and significantly improving the reliability and credibility of the counting system under complex working conditions.

[0025] 2. The physical rigidity of pressure detection effectively compensates for the environmental sensitivity of laser optical detection. Laser ranging is a non-contact optical measurement method, and its accuracy and stability are highly dependent on the optical path environment, making it extremely sensitive to interference factors such as dust, water mist, vibration, and stray light. In contrast, pressure sensors detect the rigid physical load applied to the trench bottom by the drill rod under gravity. The measurement of this physical quantity is almost unaffected by the aforementioned environmental factors—dust does not change the weight of the drill rod, water mist does not affect pressure transmission, and although vibration may introduce short-term fluctuations, these can be effectively eliminated by removing extreme instantaneous fluctuations. Therefore, the introduction of pressure detection provides the system with a stable and reliable "anchoring benchmark" even in harsh environments, complementing laser data and significantly reducing errors such as missed, over-counted, and miscounted measurements caused by environmental interference.

[0026] 3. The three-point pressure averaging layout combines counting and attitude detection functions. This invention deploys pressure sensors at the front, middle, and rear ends of the trench bottom. This not only eliminates detection errors caused by drill rod stacking eccentricity and uneven local stress through three-point averaging calculations, but also determines whether the drill rod is tilted or stuck by analyzing the pressure distribution characteristics between the three measurement points. When the three-point pressure deviation exceeds a preset threshold, the system can proactively identify stacking abnormalities and prevent the robotic arm from directly grasping the rod, avoiding equipment damage caused by forced grasping. This is a function that simple height measurement or single-point pressure measurement cannot achieve.

[0027] 4. Possesses proactive fault diagnosis and abnormal operating condition identification capabilities. The method of this invention not only achieves accurate counting after data fusion, but more importantly, it can proactively identify equipment and operational anomalies through the contradictory relationships between data. When laser data and pressure data show persistent conflict, the system can distinguish and locate the specific fault type: if the laser count is low or empty while the pressure data is stable and valid, it indicates that the laser lens may be dusty or the sensor may be faulty. The system triggers a mild warning and records the abnormal information to assist maintenance personnel in quickly locating the problem; if the laser count is normal but the pressure is close to zero, it indicates that the laser may be affected by dust reflection or noise interference, producing a false signal. The system directly rejects the laser count result, determining that the slot is empty, thus preventing false judgments due to over-counting. This proactive diagnostic capability provides data support for predictive maintenance of equipment, helping to reduce unplanned downtime.

[0028] 5. Dynamic self-calibration mechanism ensures long-term counting accuracy and reduces operation and maintenance costs. Equipment in coal mines often requires long-term continuous operation. During this time, drill rods gradually wear down, sensor sensitivity slowly drifts, and environmental temperature and humidity continuously change. These factors cause the initial calibration parameters to gradually deviate from the true values. The dynamic self-calibration mechanism designed in this invention automatically selects "high-quality samples" where the laser and pressure data are completely consistent every 80 valid count samples. It then recalculates and updates the average thickness and average pressure benchmark values ​​of a single drill rod using a progressive fine-tuning method, replacing the original calibration values. This online self-learning capability enables the system to adaptively track the slow changes in equipment and environment, maintaining high counting accuracy over the long term. It eliminates the need for regular manual disassembly and calibration, reducing the technical requirements and labor costs of on-site operation and maintenance.

[0029] 6. Simple to implement, highly compatible, and easy to promote in engineering projects. This invention fully utilizes existing resources of the drilling rig, such as laser sensors, robotic arms, and electrical controllers. Miniature explosion-proof pressure sensors are installed at the two ends and the middle of the bottom of each row of drill rod limiting slots, using existing fixed holes. This does not change any existing mechanical structure or operating procedures, and does not affect the stacking and handling of drill rods. The pressure sensors adopt a flat diaphragm explosion-proof structure, with the diaphragm flush with the bottom plane of the slot, and work in conjunction with an annular slag discharge trough to prevent coal slag accumulation. All data fusion calculations are implemented in the existing controller via software, making installation and deployment convenient, with low modification costs, and demonstrating good engineering applicability and promotional value.

[0030] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0031] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein: Figure 1 This is a block diagram of the overall counting logic of the present invention.

[0032] Figure 2 This is a simplified schematic diagram showing the installation position of the pressure sensor of the present invention. Detailed Implementation

[0033] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0034] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0035] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0036] Example 1 like Figures 1-2 The image shows a drill rod counting method that combines laser ranging and pressure averaging, applied to the drill rod box of an automatic drilling rig in an underground coal mine. The drill rod box adopts a compartmentalized structure with limiting slots, stacking and storing multiple drill rods in a single slot, making it the core material storage mechanism for intelligent drilling operations in underground coal mines.

[0037] The hardware system upon which this method is based includes a main detection unit, an auxiliary verification unit, and a data processing unit.

[0038] The main detection unit is a laser rangefinder sensor mounted on the original robotic arm of the drilling rig. It is installed on the robotic arm and driven by the robotic arm at a constant speed to scan the target limiting groove. It is used to detect the total vertical stacking height of the drill rods in a single limiting groove. The initial number of drill rods is calculated by the height-to-thickness ratio, which serves as the core counting basis.

[0039] The auxiliary verification unit includes three miniature explosion-proof pressure sensors, which are respectively positioned at the front, middle, and rear ends of the bottom of each row of drill rod limiting slots. The pressure sensors are flat diaphragm-type explosion-proof pressure sensors, with the diaphragm flush with the bottom plane of the slot and fixed using existing fixing holes. This does not alter the original mechanical structure of the limiting slots and does not affect the stacking and handling of drill rods. An annular slag discharge trough is provided at the corresponding sensor positions on the bottom of the slot to prevent slag accumulation on the sensor diaphragm surface, ensuring long-term reliable operation of the sensors. The function of the three bottom pressure sensors is to: collect the actual weight load of the drill rod stack in a single slot; calculate the average pressure at three points to eliminate detection errors caused by eccentric stacking and uneven local stress, accurately reflecting the actual total weight of the drill rods in the slot; and simultaneously, determine whether the drill rods are tilted or stuck by observing the pressure distribution characteristics between the three measurement points.

[0040] The data processing unit is the original electrical control controller of the drilling rig. All pressure sensor and laser sensor signals are connected to this electrical control controller, which realizes synchronous data acquisition, fusion calculation, verification and error correction.

[0041] Before the equipment is put into formal operation, the basic parameters are calibrated and stored in the fixed register of the electrical controller: First, the geometric parameters are calibrated by entering the standard single-layer thickness of a single-specification drill rod, the maximum number of stacked layers of a single limiting groove, and the reference height of the empty groove; then, the load parameters are calibrated by calibrating the zero-point pressure values ​​of the three pressure sensors under no-load conditions, and placing 1, 2, and 3 drill rods to the full layer respectively. After each placement, the pressure values ​​of the three pressure sensors are collected and the average value is calculated to establish a pressure-number mapping table between the average pressure and the number of drill rods; finally, the error threshold is calibrated by preset laser height deviation threshold, pressure average deviation threshold, and dual data fault tolerance verification threshold.

[0042] When used in underground coal mine working faces, each time the drilling rig initiates the drill rod inspection process, the electrical controller drives the robotic arm to move the laser rangefinder to scan the target limiting groove at a uniform speed. The laser rangefinder collects the total height of the drill rod stack within the groove; simultaneously, three pressure sensors at the bottom of the groove collect the real-time pressure values ​​applied to the drill rod stack. The acquisition of the total height signal from the laser rangefinder and the acquisition of the load signals from the three pressure sensors are performed synchronously to ensure time consistency between the two dimensions of data. All signals are connected to the existing electrical controller of the drilling rig, which performs synchronous data acquisition, fusion calculation, and error correction.

[0043] After receiving the signal of the total height of the drill rod stack in the trench from the laser sensor, the electronic controller, combined with the standard thickness of a single rod stored in the pre-calibration stage, calculates the initial number of laser beams using the following formula: Initial number of laser beams = Total stacked height ÷ Standard thickness of a single beam The calculation result is rounded to the nearest integer to obtain the number of laser counts.

[0044] After receiving the real-time pressure values ​​from the three pressure sensors, the electronic control controller first eliminates extreme values ​​of instantaneous fluctuations to remove transient abnormal data caused by drill pipe micro-jumps or electrical interference. Then, it calculates the average pressure value at the bottom of the trench from the three sensors. Finally, it combines the single-rod reference pressure load stored during the pre-calibration stage to calculate the number of pressure auxiliary counters using the following formula: Number of pressure counts = Average pressure value ÷ Single rod reference pressure load The calculation result is rounded to the nearest integer to obtain the number of pressure counters.

[0045] The counting follows the core logic of using laser counting as the primary method, pressure counting as the secondary method, and dual-source collaborative error correction. It designs hierarchical verification rules for multi-layer stacking conditions to solve the error problem of a single detection dimension.

[0046] When the difference between the laser count and the pressure average count is within the preset fault tolerance threshold, both sets of data are deemed valid. The laser count result is used as the final drill rod quantity, and the pressure data is used as the filing verification data.

[0047] When dust or vibration in the well causes the laser lens to be blocked or the beam to scatter, resulting in distorted laser height data, an underestimation or absence of laser counts, and the load signal detected by the pressure average consistently exceeds the preset minimum effective load threshold, the laser detection is deemed to have failed. The count calculated using the pressure average is taken as the final count result, and the laser sensor is marked as abnormal, triggering a mild warning. The system simultaneously records the abnormal information of the laser sensor, including the time of the abnormality, the type of abnormality, and the laser and pressure readings at that time. This information is used to help determine whether the laser sensor has lens dust accumulation, beam scattering, or sensor malfunction, providing maintenance personnel with a basis for fault location.

[0048] When the laser detects the stacking height and determines that there is a drill rod, but the average value of the three pressure sensors at the bottom of the tank is close to the zero point of no load and there is no effective load, it is determined that the laser is affected by noise and dust reflection interference, resulting in false data. The laser counting result is directly rejected, and the tank is determined to be an empty tank, thus preventing false judgments due to over-counting.

[0049] Three pressure sensors are located at the front, middle, and rear of the trench bottom, respectively. By averaging the pressure at these three points, not only can the weight be calculated, but the pressure distribution at these three points can also be used to determine whether the drill rod is misaligned or stuck. The specific method is as follows: calculate the percentage deviation between each sensor reading and the average of the three points. If the deviation of the pressure at the three points exceeds 30%, it is determined that the drill rod is not stacked correctly, and the robotic arm cannot directly grasp it. Posture adjustment or manual intervention is required first.

[0050] Throughout the counting process, the dual-source data of laser counting and pressure counting are always collected in parallel, calculated synchronously, and cross-checked. Any anomaly in one dimension can be identified and mitigated by the other dimension, ensuring that the drill rod counting results are accurate and reliable under the harsh working conditions of high dust, strong vibration, and high humidity in coal mines. This avoids faults such as the robotic arm grabbing empty, incorrect number of gripping rods, and disordered rod changing sequence, thus ensuring the stability of continuous automated drilling operations.

[0051] During long-term operation, factors such as slight wear of the drill pipe, minor attenuation of sensor sensitivity, and changes in ambient temperature and humidity can cause parameter drift. Every 80 valid count samples, the system automatically reviews these samples, selecting high-quality samples where the laser count and pressure count are completely consistent. From these samples, it recalculates the average thickness and average pressure of a single drill pipe under the current operating conditions, replacing the original calibration values ​​with a gradual fine-tuning approach, and automatically updating the pre-stored reference pressure load and standard thickness of the single drill pipe. This process is executed automatically and silently in the background of the electrical control controller, requiring no manual disassembly or calibration, thus ensuring long-term counting accuracy.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A drill pipe counting method that integrates laser ranging and average pressure, characterized in that, Includes the following steps: S1. Multiple pressure sensors are installed at the bottom of the drill rod limiting groove to collect the pressure load signal of the drill rod in the groove; at the same time, a laser rangefinder is used to collect the total height signal of the drill rod stack in the groove. S2. Based on the total height signal and combined with the pre-stored standard thickness of a single drill rod, the number of laser counts is calculated. S3. Based on the pressure load signals of the multiple pressure sensors, calculate the average pressure value, and combine it with the pre-stored single-rod reference pressure load to calculate the number of pressure counts. S4. Compare and verify the number of laser counts with the number of pressure counts, and determine the final number of drill rods according to the preset verification rules.

2. The method according to claim 1, characterized in that, In step S1, the signals from the laser rangefinder and multiple pressure sensors are all connected to the existing electrical control controller of the drilling rig, and the electrical control controller realizes synchronous data acquisition, fusion calculation and verification and error correction.

3. The method according to claim 1, characterized in that, In step S1, the total height signal acquisition of the laser rangefinder sensor and the weight load signal acquisition of multiple pressure sensors are carried out simultaneously.

4. The method according to claim 1, characterized in that, In step S1, the laser rangefinder is mounted on the drilling rig's robotic arm, which drives the scanning of the target limiting groove at a constant speed to collect the total height of the drill rod stack within the groove.

5. The method according to claim 1, characterized in that, The multiple pressure sensors consist of three units, which are respectively located at the front, middle, and rear ends of the bottom of the drill rod limiting groove. They are used to calculate the average pressure at three points to eliminate detection errors caused by drill rod stacking eccentricity and uneven local force.

6. The method according to claim 1, characterized in that, The pressure sensor is a flat diaphragm explosion-proof pressure sensor, with its diaphragm installed flush with the bottom plane of the tank; the bottom of the tank is provided with an annular slag discharge trough to prevent coal slag from accumulating on the surface of the sensor diaphragm.

7. The method according to claim 1, characterized in that, The multiple pressure sensors are installed and fixed through the original fixing holes at the bottom of the drill rod limiting groove, without changing the original mechanical structure of the drill rod limiting groove, and without affecting the stacking and picking up / dropping of the drill rod.

8. The method according to claim 1, characterized in that, The method also includes a parameter pre-calibration step performed before the operation, specifically including: Geometric parameter calibration: Enter the standard single-layer thickness of a single-specification drill pipe, the maximum number of stacked layers in a single limiting groove, and the reference height of the empty groove; Load parameter calibration: The zero-point pressure value of each pressure sensor is calibrated under no-load conditions, and the pressure value under the corresponding conditions is collected by placing different numbers of drill rods respectively, and a pressure-number mapping table is established. Error threshold calibration: preset laser height deviation threshold, pressure average deviation threshold and dual data fault tolerance verification threshold.

9. The method according to claim 8, characterized in that, The method for establishing the pressure-number mapping table is as follows: place 1, 2, and 3 drill rods to the full layer, collect the pressure values ​​of three pressure sensors under each quantity condition, calculate the average value, and form a correspondence between the average pressure value and the number of drill rods.

10. The method according to claim 1, characterized in that, In step S2, the formula for calculating the number of laser beams is: initial number of laser beams = total stacking height ÷ standard thickness of a single beam.

11. The method according to claim 1, characterized in that, In step S3, before calculating the average pressure value, the instantaneous fluctuation extreme values ​​of each pressure sensor signal are first eliminated; the formula for calculating the number of pressure counts is: number of pressure counts = average pressure value ÷ single rod reference pressure load.

12. The method according to claim 1, characterized in that, The verification rules in step S4 include: When the difference between the laser count and the pressure count is within the preset fault tolerance threshold, both sets of data are deemed valid. The laser count result is used as the final drill rod quantity, and the pressure data is used as the filing verification data. When the number of laser counts is abnormal while the number of pressure counts detects a stable effective load signal, the laser detection is determined to be faulty. The pressure count is used as the final count result, and the laser sensor is marked as abnormal, triggering a mild warning. When the laser counting count indicates the presence of a drill rod while the pressure counting count is close to the zero point under no load, the laser detection is deemed to be generating false data, the laser counting result is rejected, and the slot is determined to be empty.

13. The method according to claim 12, characterized in that, The specific conditions for determining laser detection failure are: the number of laser counts is too small or empty, and the load signal detected by the average pressure value consistently exceeds the preset minimum effective load threshold.

14. The method according to claim 12, characterized in that, When there are three pressure sensors, the verification rule also includes: judging whether the drill pipe stacking is abnormal by comparing the pressure distribution deviation between the readings of the three pressure sensors and the average pressure value; if the pressure deviation at any point exceeds the preset abnormal threshold, it is determined that the drill pipe stacking is not correct and the robot arm cannot directly grasp it.

15. The method according to claim 1, characterized in that, The method also includes a dynamic self-calibration step: every set number of valid count samples, samples with the same number of laser counts and pressure counts are automatically selected, the average pressure and average thickness of a single rod are recalculated, and the pre-stored single rod reference pressure load and single rod standard thickness are updated in a progressive fine-tuning manner.

16. The method according to claim 15, characterized in that, In the dynamic self-calibration step, the effective number of count samples is set to 80.

17. The method according to claim 12, characterized in that, While triggering a mild warning, the system records abnormal information from the laser sensor to help determine whether the laser sensor has lens dust accumulation, beam scattering, or sensor malfunction.

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