Mobile device for analyzing ore fragmentation in underground blasting and analysis method

Abstract

The application discloses a mobile ore blockiness analysis device and method for underground blasting, and belongs to the technical field of mine engineering, and comprises an illumination unit, an optical distance measuring unit and a photographing unit. Through the arrangement of the optical distance measuring unit, the geometric parameters of the ore pile observation area are determined, the size reference is provided for the image collected by the photographing unit, the core target that the image size can be corrected without reference to the vertical angle and the scale ruler is realized, and therefore the problem that the traditional scale calibration is easily affected by the uneven ore pile and the angle deviation is solved.

Description

Technical Field

[0001] This invention belongs to the field of mining engineering technology, and in particular relates to a mobile underground blasting ore block size analysis device and analysis method. Background Technology

[0002] Statistical analysis of blasted ore block size is an important task in assessing whether blasting has achieved its design goals. However, the current method for statistical analysis of blasted ore block size still requires placing a ruler on the ore pile and taking pictures from a direction perpendicular to the ruler to obtain an image of the ore pile, and then analyzing the image based on this image. This method often results in errors in the ruler calibration due to the uneven surface of the ore pile, leading to poor measurement accuracy.

[0003] Therefore, it is necessary to provide an apparatus capable of obtaining high-analytical-value images of ore heaps from a specific angle, and a method for performing block size analysis of ore heaps based on these images. Summary of the Invention

[0004] In view of the technical problems existing in the background art, this application provides a mobile underground blasting ore block size analysis device, including a mobile main body, an illumination unit, an optical ranging unit, and an imaging unit, wherein:

[0005] The lighting unit is mounted on the mobile main body and is used to supplement the light source in the ore pile observation area.

[0006] The optical ranging unit is mounted on the mobile main body, and at least four units are provided, for measuring the distance between the vertices of the quadrilateral within the observation range of the ore pile and the observation point.

[0007] The photographing unit is mounted on the mobile main body and is used to capture images of the ore pile and delineate the block size outline.

[0008] In some embodiments, four optical ranging units are provided, and the optical ranging units are respectively located at four positions on the end face of the device facing the observation surface. The central angle between two adjacent positions is 90 degrees, and the optical sights of each optical ranging unit are arranged in an outward pattern in a direction away from the central axis of the device and pointing towards the observation surface of the ore pile.

[0009] This application also provides a method for analyzing the size of blasted ore blocks using the mobile underground blasting ore block size analysis device provided in this application, including:

[0010] Turn on the lighting unit for supplemental lighting to determine the block size analysis area;

[0011] Press the analysis button, and the camera unit will automatically focus and the optical rangefinder unit will be activated simultaneously to adjust the position of the quadrilateral vertices.

[0012] Press the analysis button again to complete image acquisition and distance measurement;

[0013] Perform data processing to obtain block-level data.

[0014] In some implementations, the process of performing data processing and obtaining block-level data includes:

[0015] Based on the distance between the vertices of the quadrilateral measured by the optical ranging unit and the included angle between the optical ranging units, the side length, diagonal length, and perpendicular distance between the device and the observation plane of the ore pile are calculated.

[0016] The rock outline in the image of the ore pile captured by the imaging unit is projected onto the quadrilateral recognition area. A planar screen grid is constructed by taking one diagonal of the quadrilateral as a reference and combining it with the perpendicular line to the other vertex of the diagonal.

[0017] The maximum closed loop area formed by the grid lines intersecting with the rock outline is defined as the minimum grid area S1 of the rock screen, and the area formed by expanding S1 outward by one grid ring is defined as the maximum grid area S2 of the rock screen.

[0018] The range of ore block size was determined by using the equivalent block size analysis method.

[0019] In some embodiments, after projecting the rock contour circle in the ore pile image captured by the imaging unit onto the quadrilateral recognition area, the data processing to obtain block size data further includes:

[0020] Rock edge detection is performed on the identified area and surrounding ore piles to delineate the planar closed loops of each rock block size, forming a composite map of rock block size closed loops.

[0021] In some embodiments, the equivalent block size analysis method is as follows:

[0022] If the aspect ratio of the rock outline is greater than or equal to 2.5, then the ore particle size range is taken as the grid width corresponding to S1 and S2.

[0023] If the aspect ratio of the rock profile is less than 2.5, then the ore particle size range is between and between.

[0024] In some embodiments, after determining the range of ore block size using the equivalent block size analysis method, the underground blasting ore block size analysis method further includes:

[0025] Using the other diagonal of the quadrilateral as a reference, the grid construction process is repeated to identify and statistically analyze the ore block size distribution range that intersects with the first diagonal, and then incorporate it into the block size analysis results.

[0026] In some implementations, pressing the analysis button again to complete image acquisition and ranging also includes:

[0027] Take multiple photos of the same ore pile from different angles, and accumulate the block size frequency and frequency of each analysis according to the preset block size range.

[0028] In some implementations, pressing the analysis button again to complete image acquisition and ranging also includes:

[0029] The surface block size of the ore pile in the same mining area was photographed multiple times at different time periods after it was shoveled, and the block size frequency and frequency of each analysis were accumulated according to the preset block size range.

[0030] In some embodiments, after data processing and obtaining block size data, the underground blasting ore block size analysis method further includes:

[0031] Output block size data; wherein, the block size data includes median block size, average block size and 80% sieve size; the output format includes frequency distribution histogram and cumulative frequency distribution chart.

[0032] This application provides a mobile underground blasting ore block size analysis device, including a mobile main body, an illumination unit, an optical ranging unit, and an imaging unit. The mobile main body fixes the positions of each functional unit, ensures stable angular relationships between units, and adapts to underground moving environments, providing rigid support for subsequent coordinated work of illumination, ranging, and imaging, avoiding analysis errors caused by unit shaking or displacement. The illumination unit provides a non-reflective, shadow-free, and highly uniform lighting environment for the imaging unit, ensuring clear and discernible ore block size outlines, enhancing the analytical value of the images, and solving the problems of uneven underground lighting and ore block shadows. To address the issue of blurry images, the optical ranging unit measures the geometric parameters of the ore pile observation area, including side length, diagonal, and vertical distance. This provides a true size reference for the images captured by the imaging unit, achieving the core objective of correcting image size even without the reference of vertical angles and rulers. This solves the problem that traditional ruler calibration is easily affected by unevenness and angular deviations in the ore pile. By setting up the imaging unit, images of the ore pile are acquired and the block size outline is subsequently delineated. Combined with the geometric parameters provided by the optical ranging unit, the image pixel size is converted into the actual size of the ore pile, enabling image output that obtains accurate block size information even without a specific angle.

[0033] This application also provides a method for analyzing the block size of blasted ore using the mobile underground blasting ore block size analysis device provided in this application. The method includes: activating the lighting unit for supplemental lighting to determine the block size analysis area; pressing the analysis button, which automatically focuses the camera unit and simultaneously activates the optical ranging unit to adjust the position of the quadrilateral vertices; pressing the analysis button again to complete image acquisition and ranging; and processing the data to obtain block size data. By activating the lighting unit for supplemental lighting to determine the block size analysis area, the problem of image distortion caused by low underground lighting and ore pile protrusions is solved. The steps of automatically focusing the camera unit and simultaneously activating the optical ranging unit to adjust the position of the quadrilateral vertices by pressing the analysis button address the large calibration error of manual rulers and reliance on vertical shooting angles. Pressing the analysis button again to complete image acquisition and ranging ensures the synchronous acquisition and storage of image data and other data, thereby strengthening the correlation between data and providing data basis for subsequent calculations. Data processing yields block size data, thus obtaining the block size distribution data of the ore pile. Attached Figure Description

[0034] To more clearly illustrate the technical solutions of this application, the accompanying drawings used in this application will be briefly described below. Obviously, the drawings described below are merely some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without any creative effort.

[0035] Figure 1 This is a front structural schematic diagram of a mobile underground blasting ore block size analysis device provided in an embodiment of this application;

[0036] Figure 2 This is a side view of a mobile underground blasting ore block size analysis device provided in an embodiment of the present invention;

[0037] Figure 3 This is a schematic diagram illustrating the operation method of a mobile underground blasting ore block size analysis device provided in an embodiment of the present invention;

[0038] Figure 4 This is a schematic diagram of the positional relationship between the quadrilateral observation space and the observation points formed by a mobile underground blasting ore block size analysis device provided in an embodiment of the present invention;

[0039] Figure 5 This is a schematic diagram of selecting the S1 and S2 borders when generating a planar screen grid with the diagonal AC as the reference, according to an embodiment of the present invention for a method for analyzing the block size of blasted ore in underground mining;

[0040] Figure 6 This is a schematic diagram of the planar screen grid defined by S1 and S2 in a method for analyzing the block size of blasted ore provided in an embodiment of the present invention;

[0041] Figure 7 This is a diagonal schematic diagram of a method for analyzing the block size of blasted ore in underground mining, provided in an embodiment of the present invention.

[0042] Figure 8 This is a schematic diagram of selecting the S1 and S2 borders when generating a planar screen grid based on the diagonal BD, according to an embodiment of the present invention for a method for analyzing the block size of blasted ore in underground mining;

[0043] Figure 9 This is a basic flowchart of a method for analyzing the block size of blasted ore in underground mines, provided by an embodiment of the present invention.

[0044] Figure 10 This is an optimized flowchart illustrating the steps for data processing and obtaining block size data in an underground blasting ore block size analysis method provided by an embodiment of the present invention.

[0045] Figure 11 This is a schematic diagram of a further optimized process for the steps of data processing and obtaining block size data in an underground blasting ore block size analysis method provided in an embodiment of the present invention;

[0046] Figure 12 This is a schematic diagram of an optimized process for an efficient block size analysis method in the steps of data processing and obtaining block size data, provided by an embodiment of the present invention for analyzing the block size of blasted ore in underground mines.

[0047] Figure 13 This is an optimized flowchart illustrating the process of constructing a repeating grid based on another diagonal line, as provided in an embodiment of the present invention for a method for analyzing the block size of blasted ore in underground mining.

[0048] Figure 14 This is an optimized flowchart of a method for analyzing the block size of blasted ore in underground mines, provided by an embodiment of the present invention, from another perspective.

[0049] Figure 15 This is a schematic diagram of the optimized process for analyzing the block size of blasted ore in underground mines at different time periods, provided by an embodiment of the present invention.

[0050] Figure 16 This is a schematic diagram of an optimized process for analyzing the block size of blasted ore in underground mines, including the output of block size data, provided by an embodiment of the present invention.

[0051] Explanation of reference numerals in the attached diagram: 1. Illumination unit; 2. Optical ranging unit; 3. Photographing unit; 4. Data processing and storage unit; 5. Power supply unit; 6. Result output and display unit; 7. Ore boundary outline; 8. Minimum grid area S1 of rock screen; 9. Maximum grid area S2 of rock screen. Detailed Implementation

[0052] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0054] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0055] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0056] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0057] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0058] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to 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, they should not be construed as limitations on the embodiments of this application.

[0059] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0060] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0061] In some implementations, refer to Figures 1 to 3 A mobile underground blasting ore block size analysis device includes a mobile main body, an illumination unit 1, an optical ranging unit 2, and an imaging unit 3, wherein:

[0062] The mobile main body is a prefabricated frame structure used to support the various units inside the carrying device and to create angular relationships between the units. It integrates the various parts of the device and facilitates operator gripping and movement, or is mounted on mine cars, trolleys, or flatbed carts for easy movement within the mine tunnel. For example, the mobile main body is made of explosion-proof, water-resistant, and antistatic aluminum alloy and is cylindrical in shape. It should be noted that the mobile main body can also take other shapes. For example, it can be an irregular cylinder with recesses on the side walls to accommodate gripping angles; or it can be a polygonal column. Again, taking a cylindrical shape as an example, the cylinder has a diameter of 8 cm and a length of 15 cm, with an integrally formed arc-shaped handle in the center of its outer wall for manual gripping and angle adjustment. The outer shell of the mobile main body is divided into two semi-circular arc shell structures along the axial direction, which are fastened together by edge snaps.

[0063] The movable main body has a front cavity, a middle cavity, and a rear cavity arranged along the axis. The front cavity is used to accommodate and fix three units: the illumination unit 1, the optical ranging unit 2, and the imaging unit 3. Correspondingly, the front cavity has three slots to correspond to the setting of each unit, thereby providing a stable working foundation for each unit and avoiding measurement errors caused by the shaking of the main body of each unit.

[0064] The lighting unit 1 is mounted on the mobile main body to supplement the light source in the observation area of ​​the mine pile. Specifically, the lighting unit 1 is located at the front end of the front cavity of the mobile main body, thereby providing supplementary lighting for the shooting of the photography unit 3. For example, the lighting unit 1 adopts a ring-shaped LED lighting module with an inner diameter of 5 cm and a width of 1 cm. It has 12 built-in LED beads with a power of 2.5 watts per bead, a total power of 30 watts, and a maximum lumen of 2000 lumens, providing a high-definition, non-reflective image acquisition environment for the photography unit 3 and improving the image quality of the photography unit 3.

[0065] It should be noted that the lighting unit 1 can be any structure that can be integrated into the front end of the mobile body and provide illumination for the camera unit 3. For example, the lighting unit 1 includes two rectangular COB surface light source modules, which are symmetrically integrated on both sides of the front end of the mobile body and set on the left and right sides of the camera unit 3.

[0066] Optical ranging units 2, disposed on the movable main body, and at least four in number, are used to measure the distance between the vertices of the quadrilateral within the observation range of the ore pile and the observation point. Specifically, the core technical objective of this application is to replace the traditional calibration method of ruler + vertical photography. This requires measuring the geometric dimensions of the observation area using optical ranging units 2, thereby constructing a virtual screen to delineate and analyze the block size contour. Therefore, the number of ranging units directly determines the geometric dimensions of the observation area and the feasibility and accuracy of the calculation, thus affecting the derivation of the two-dimensional planar morphology of the ore pile. From the perspective of geometric principles and technical solution implementation, four units are the minimum number required to calculate the two-dimensional dimensions of the ore pile observation area. This is because four optical ranging units 2, evenly distributed along the circumference of the front cavity of the device, can determine the distance data of the four vertices, which can be calculated using trigonometric functions. The device observes the side length, diagonal length, and perpendicular distance between the device and the observation plane of the ore pile. These parameters are then combined with images acquired by the imaging unit 3 to obtain the actual size of the ore pile. If three optical ranging units 2 are set, there will be no redundant calculation to correct errors during coordinate fitting, resulting in decreased plane fitting accuracy and increased perpendicular distance error, thus affecting calculation accuracy. If more than four optical ranging units 2 are set, such as five, the observation light point formed by the additional optical ranging units 2 will be set on one of the sides of the quadrilateral. The additional ranging units can capture the irregular contour protrusions or depressions of the ore pile, thereby improving the accuracy and reliability of contour fitting. However, this will affect the portability of the device. Therefore, more optical ranging units 2 are only added when there are higher requirements for block size accuracy.

[0067] For example, each optical ranging unit 2 is an independent laser ranging module. The module output is connected to the power supply line inside the main body through a waterproof data cable. The four optical ranging units 2 are evenly distributed circumferentially along the annular slot of the front cavity, with the included angle between adjacent units being 90°, thereby ensuring that the measured quadrilateral is a regular rectangle or parallelogram, which facilitates subsequent image size correction. For example, the four optical ranging units 2 are arranged and installed in a way that two are on the upper layer and two are on the lower layer, with the two layers spaced 1-2 cm apart along the axial direction of the front cavity, and the two units in each layer are symmetrically distributed circumferentially, thereby adapting to the measurement of long and narrow ore piles in narrow underground tunnels. For example, the four optical ranging units 2 are still evenly distributed circumferentially along the front cavity, but each unit is connected to the front cavity slot through a micro rotating shaft, thereby allowing the optical ranging unit 2 to be independently adjusted to adapt to irregularly shaped ore piles.

[0068] The imaging unit 3, mounted on the mobile main body, is used to acquire images of the ore pile and delineate the block size contours. Specifically, the imaging unit 3 mainly captures actual images of the ore blocks within the observation surface delineated by the optical ranging unit 2. Combined with the parameters measured by the optical ranging unit 2, the actual image size is corrected for subsequent block size delineation, and the actual block size distribution is obtained through analysis. For example, the imaging unit 3 is positioned at the center of the front cavity of the mobile main body, located at the annular center of the illumination unit 1 and the optical ranging unit 2, and is positioned by a circular slot in the center of the cavity, with the lens centerline completely aligned with the main body axis. For example, a circular mounting hole adapted to the volume of the imaging unit 3 is opened in the front cavity, while retaining buffer space. Elastic buffer pads are evenly distributed circumferentially on the inner wall of the hole. After the imaging unit 3 is embedded, it achieves initial positioning through the buffer pads. Simultaneously, an annular pressure cap is provided on the back of the front cavity, with a wave spring between the inner side of the pressure cap and the imaging unit 3 to prevent the image center from shifting from the laser convergence point due to mine vibration.

[0069] This application provides a mobile underground blasting ore block size analysis device, including a mobile main body, an illumination unit 1, an optical ranging unit 2, and an imaging unit 3. The mobile main body fixes the positions of each functional unit, ensures stable angular relationships between units, and adapts to underground mobile scenarios, providing rigid support for subsequent coordinated work of illumination, ranging, and imaging, avoiding analysis errors caused by unit shaking or displacement. The illumination unit 1 provides the imaging unit 3 with a non-reflective, shadow-free, and highly uniform lighting environment, ensuring clear and discernible ore block size outlines, enhancing the analytical value of the images, and solving the problems of uneven underground lighting and ore block shadows. To address the issue of image blurring, the optical ranging unit 2 measures the geometric parameters of the ore pile observation area, including side length, diagonal, and vertical distance, providing a true size reference for the image captured by the imaging unit 3. This achieves the core objective of correcting image size even without the reference of vertical angles and rulers, thus solving the problem that traditional ruler calibration is easily affected by unevenness and angular deviations in the ore pile. By setting up the imaging unit 3, the ore pile image is captured and the block size outline is subsequently delineated. Combined with the geometric parameters provided by the optical ranging unit 2, the image pixel size is converted into the actual size of the ore pile, enabling image output that can obtain accurate block size information even without a specific angle.

[0070] In some implementations, refer to Figure 2There are four optical ranging units 2. The optical ranging units 2 are respectively located at the four positions of the end face of the device facing the observation surface. The central angle between two adjacent positions is 90 degrees. The optical sights of each optical ranging unit 2 are arranged in an outward pattern, pointing away from the central axis of the device and towards the observation surface of the ore pile. Specifically, given that the function of the optical ranging unit 2 is to measure the distance between the vertices of the quadrilateral within the observation range of the ore pile and the observation point, this embodiment further specifies the specific installation method of the optical ranging unit 2. Specifically, the optical ranging units 2 are respectively positioned at four points on the end face of the device facing the observation surface, with the central angle between adjacent points being 90 degrees. The optical sights of each optical ranging unit 2 are arranged radially outwards, pointing away from the central axis of the device and towards the observation surface of the ore pile. On the one hand, by limiting the optical ranging units 2 to be positioned at four points on the end face of the device facing the observation surface, with the central angle between adjacent points being 90 degrees, when the device is directly facing the observation surface of the ore pile, the vertices of the quadrilateral within the observation range of the ore pile measured by the four optical ranging units 2 have adjacent vertices equidistant from the device, forming a regular rectangle when connected. On the other hand... When the device is tilted, although the distance between the individual vertices of the four optical ranging units 2 and the device differs due to the tilt, the 90-degree angle between adjacent units remains unchanged, and the symmetry between the unit and the central axis remains unchanged. At this time, the measured quadrilateral is still a parallelogram. By correcting the tilt error through trigonometric functions, it can be restored to a regular shape, thereby ensuring that the quadrilateral of the measured ore pile observation range is a regular rectangle or parallelogram, simplifying the subsequent image size correction algorithm logic and reducing the complexity of data processing. On the other hand, by limiting the optical sights of each optical ranging unit 2 to be arranged outward in a direction away from the central axis of the device and pointing towards the ore pile observation surface, the optical ranging unit 2 can form a larger observation surface, while ensuring that the optical paths of each unit do not intersect within the observation distance, and at the same time, it does not block the lens optical path of the imaging unit 3.

[0071] In some implementations, refer to Figure 2 The device also includes a data processing and storage unit 4 for processing and storing data, a power supply unit 5 for supplying power to the entire device, and a result output and display unit 6 for human-computer interaction.

[0072] This application also provides a method for analyzing the size of blasted ore using the mobile underground blasting ore size analysis device disclosed in this application, referring to... Figure 9 ,include:

[0073] S101. Activate the lighting unit to supplement light and determine the block size analysis area. This step relies on the lighting unit of this device to provide supplementary lighting for subsequent photography and ranging work, avoiding image distortion caused by low underground lighting and ore pile protrusions. For example, the operator holds the device with one hand and presses the lighting control switch located on the side or top of the device handle with their thumb to activate the lighting unit, covering the ore pile area with light, and observes the supplementary lighting effect through the rear screen of the output and display unit. Using the real-time imaging of the display screen as a reference, move the device back and forth to ensure that the ore pile area to be analyzed is completely displayed on the screen without edge truncation and without glare on the screen.

[0074] S102. Press the analysis button. The camera unit automatically focuses, and the optical ranging unit is activated simultaneously. Adjust the position of the quadrilateral vertices. This step utilizes the control unit, camera unit, and optical ranging unit of this device to acquire both images and parameters. The camera unit focuses and locks the observation area, and the optical ranging unit emits lasers to calibrate the quadrilateral vertices. Manual fine-tuning ensures that the vertices cover the key areas of the ore pile, avoiding image misalignment in subsequent data acquisition. For example, the operator presses the analysis button on the side or top of the handle with their index finger. The camera unit located in the center of the front cavity of the device focuses. The focus area is preset to the quadrilateral observation area. Manual fine-tuning ensures that the area falls completely within the camera range. The four optical ranging units simultaneously emit lasers, and the laser points form four red dots on the surface of the ore pile. At the same time, the real-time distance data between the four vertices and the device is obtained. The operator observes the position of the four laser dots on the display screen to ensure that all dots are clearly visible. Thus, based on image acquisition, the calibration capability of the optical ranging unit is combined to avoid the deviation caused by the use of a ruler for calibration in traditional methods, and it also eliminates the dependence on vertical shooting methods.

[0075] S103. Press the analysis button again to complete image acquisition and distance measurement. Specifically, after confirming that the position of the quadrilateral vertices is correct, the operator presses the analysis button again. The camera unit completes the acquisition of one image of the ore pile and associates it with the acquisition timestamp. The four optical distance measurement units simultaneously record the distance data between the four vertices and the device. The data is also associated with the same timestamp, thereby obtaining the necessary data for block size analysis.

[0076] S104. Perform data processing and obtain block size data. For example, the data processing unit of the device uses a dynamic grid adaptive method for data processing. First, it performs grayscale analysis on the acquired ore pile image and uses the Otsu threshold segmentation algorithm to divide the image into high-density ore block areas and low-density ore block areas. It calculates the actual side length by combining the four vertices of the quadrilateral, thereby matching the initial grid for different areas. The high-density ore block area uses a fine grid, and the low-density ore block area uses a coarse grid for calculation. Then, the initial particle size range of each ore block is calculated by dynamically adjusting the grid to complete the coarse block size calculation. Then, the boundary fitting optimization is performed to output a grayscale partition map, a dynamic grid adjustment diagram, and a block size frequency and frequency dual-axis graph, thereby providing data for blasting design.

[0077] In some implementations, refer to Figure 10 In step S104, data processing to obtain block-level data includes:

[0078] S1041. Based on the distance between the vertices of the quadrilateral measured by the optical ranging unit and the included angle between the optical ranging units, calculate the side length, diagonal length, and perpendicular distance between the device and the observation plane of the ore pile, thereby establishing the actual geometric coordinate system of the ore pile observation area. This provides a true size scale for subsequent image projection and screen construction, avoiding block size calculation deviations caused by image stretching. For example, refer to... Figure 4 The optical ranging results of the four vertices of the quadrilateral are set as four points A, B, C, and D. The distances between the vertex positions and the device are set as a, b, c, and d respectively. According to the adjacent included angle α and the relative included angle 2β of the optical sights inside the device, relevant trigonometric function calculations are performed to accurately obtain parameters such as the spatial shape of the quadrilateral and the perpendicular distance between the device and the recognition plane.

[0079] Among them: the formula for calculating the side length of a quadrilateral is as follows: Figure 4 For example, AB in the middle is as follows:

[0080]

[0081] The formula for calculating the length of the diagonal of a quadrilateral is as follows: Figure 4 For example, in Chinese AC:

[0082]

[0083] Vertical distance between device and recognition plane Calculation formula, with Figure 4 For example, see below:

[0084]

[0085]

[0086]

[0087] The perpendicular line from point B to triangle ABC Calculation formula, with Figure 4 For example, see below:

[0088]

[0089]

[0090] S1042. Project the rock contour circle in the ore pile image captured by the imaging unit onto the quadrilateral recognition area. Using one diagonal of the quadrilateral as a reference, and combining it with the perpendicular line to the other vertex of the diagonal, construct a planar screen grid; for example, refer to Figure 5 The results are calculated by taking the line AC connecting the two diagonal points of the identified region as the reference and the perpendicular line and length to the corresponding other vertices B and D. , , As a scale, a planar screen grid is constructed, which is divided into two triangular regions by AC. The grid size is 50 mm × 50 mm. During the statistics, only the block size of the ore that does not intersect with AC is considered.

[0091] Reference Figure 6 S1043. The maximum closed loop area formed by the grid lines intersecting the rock contour line is defined as the minimum grid area S1 of the rock sieve. The area formed by expanding S1 outward by one ring of grid lines is defined as the maximum grid area S2 of the rock sieve. Specifically, the device data processing unit traverses each rock contour circle, identifies all grid lines intersecting the contour line, and defines the area of ​​the minimum closed region completely enclosing the rock contour circle as S1. Based on the minimum closed region corresponding to S1, one ring of grid lines is expanded outward, that is, a layer of grid lines is added along the outer perimeter of the closed region to form a complete closed region. The area of ​​a closed region encompassing S1 and extending outwards is defined as S2, thus obtaining a reference interval reflecting the minimum and maximum coverage areas of the rock block, facilitating subsequent equivalent block size analysis. For example, if the rock outline intersects with 3×3 grid lines and the minimum closed region is 2×2 grids, then S1 = 2×2×(grid size)². Based on S1, after extending outwards, there are 4×4 grids, then S2 = 4×4×(grid size)², ensuring that the extended grid completely covers the protruding edge of the rock outline, avoiding accuracy reduction due to irregular outlines.

[0092] S1044. The range of ore block size is determined by equivalent block size analysis. Based on S1 and S2, the area parameter is converted into a block size range by the equivalent block size algorithm, which adapts to the morphological characteristics of irregular rock blocks and solves the error problem caused by the traditional method of using the longest side as the block size.

[0093] In some implementations, refer to Figure 11 S1042, after the rock contour circle in the ore pile image acquired by the imaging unit is projected onto the quadrilateral recognition area, it also includes:

[0094] S10421. Perform rock edge detection on the identified area and surrounding ore piles, delineate the planar closed loops of each rock block size, and form a composite image of rock block size closed loops. For example, based on the quadrilateral identified area, extend outward by 5 cm to cover the edge ore blocks around the identified area, thereby avoiding missing ore blocks; use the Canny operator to perform rock edge detection on the identified area and surrounding ore piles, delineate the planar closed loops of each rock block size, and project them onto the identified area to form a composite image of rock block size closed loops, which is beneficial for the definition of S1 and S2 in the next step.

[0095] In some implementations, refer to Figure 12 The equivalent particle size analysis method in S1044 is as follows: if the aspect ratio of the rock profile is greater than or equal to 2.5, the particle size range of the ore is taken from the grid widths corresponding to S1 and S2; if the aspect ratio of the rock profile is less than 2.5, the particle size range of the ore is between... and Specifically, for elongated and flaky ores commonly found in underground blasting, the particle size is calculated using a grid width method. This avoids particle size deviations caused by the elongated shape of the ore, ensuring that the block size data reflects the actual flow characteristics of the ore. For example, if the circumscribed rectangle of an elongated ore has the following parameters: length L = 250 mm, width W = 80 mm, then its aspect ratio is R = 250 / 80 = 3.125 > 2.5, and its particle size is 60 mm - 120 mm. For blocky and short columnar ores in the core area of ​​underground ore piles, the equivalent particle size is directly and quickly converted based on the area. For example, if a near-square ore block has a length L = 150 mm and a width W = 120 mm, then its aspect ratio is 1.25, and its particle size is 120 mm to 150 mm. This avoids the problem of large fluctuations in the block size coefficient due to significant differences in ore block shape, making quantification difficult.

[0096] In some implementations, refer to Figure 13 After determining the range of ore block size using the equivalent block size analysis method in S1044, the underground blasting ore block size analysis method further includes: S1045, using the other diagonal of the quadrilateral as a reference, repeating the grid construction process, identifying and statistically analyzing the ore block size distribution range intersecting with the first diagonal, and incorporating it into the block size analysis results. Specifically, refer to... Figure 7When using a single diagonal to form the screen grid, the size of overlapping ore blocks on the diagonal is not counted. Therefore, this method, based on the single diagonal screen in S1042, constructs a new planar screen grid using a screen along another diagonal, thereby completing the size data for ore crossing diagonals. First, a screen is constructed using the first diagonal to count non-intersecting ore blocks, then a screen is constructed using the second diagonal to count intersecting ore blocks, finally integrating them into a complete size result, avoiding omissions due to a single screen reference. For example, refer to... Figure 8 Based on the planar screen constructed with AC as the reference and the data of non-intersecting ore blocks that have been statistically analyzed, a screen is constructed with the BD diagonal as the new reference. The same size grid is used to form the BD reference screen. The BD reference screen is used to identify ore blocks that cross the AC diagonal, calculate their block size distribution range and include them in the statistics, thereby improving the accuracy of ore block size analysis.

[0097] In some implementations, refer to Figure 14 In step S103, pressing the analysis button again completes the image acquisition and ranging process, which also includes:

[0098] S1031. Take multiple photos of the same ore pile from different angles, and accumulate the block size frequency and relative frequency of each analysis according to a preset block size interval. Specifically, utilizing the mobile and portable nature of this device, the same ore pile is photographed multiple times from different angles to supplement any obstructed or edge blocks missed in a single acquisition. The frequency and relative frequency are then accumulated to reduce random errors, solving the problem of incomplete block size statistics due to ore pile obstruction and angle deviation in a single acquisition, thus improving the accuracy of underground ore pile block size analysis. For example, for each preset angle, the supplementary lighting, focusing, and acquisition process is repeated, and the data is stored in groups. After processing, block size interval data from multiple acquisitions is obtained, and the frequency is calculated after accumulation to obtain a block size distribution frequency table.

[0099] In some implementations, refer to Figure 15 In step S103, pressing the analysis button again completes the image acquisition and ranging process, which also includes:

[0100] S1032. Take multiple photos of the surface block size of the same mining pile after loading at different time periods, and accumulate the block size frequency and relative frequency of each analysis according to the preset block size range. By taking photos at different time periods after loading the mining pile, the deep ore blocks exposed by loading and dynamically changing surface ore blocks that were missed in a single collection and collection at the same time are supplemented. Then, by accumulating the frequency and relative frequency, the statistical bias caused by the dynamic changes of the mining pile is reduced, thereby adapting to the working conditions of dynamic changes in the surface morphology of the mining pile during loading.

[0101] In some implementations, refer to Figure 16After processing the data and obtaining the block size data in S104, the underground blasting ore block size analysis method further includes:

[0102] S105. Output block size data. This block size data includes the median block size, average block size, and 80% sieve size. The output formats include a frequency distribution histogram and a cumulative frequency distribution chart. Specifically, the median block size reflects the block size concentration trend, the average block size reflects the overall block size level, and the 80% sieve size reflects the block size screening characteristics, which are related to the selection of underground crushing equipment and the design of the ore pass size. The frequency distribution histogram reflects the distribution of the number of ore blocks in each interval; the cumulative frequency distribution chart reflects the cumulative slope percentage pattern.

[0103] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.

[0104] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.

Claims

1. A mobile in-mine blast rock fragmentation analysis method, characterized by, The application is applied to a mobile underground blasting ore block size analysis device, which comprises a mobile main body, an illumination unit, an optical distance measuring unit and a photographing unit, wherein: The illumination unit is arranged on the mobile main body and is used for supplementing the light source of the ore pile observation area. The optical distance measuring unit is arranged on the mobile main body and is provided with at least four units for measuring the distance between the quadrilateral vertexes of the ore pile observation range and the observation point. The photographing unit is arranged on the mobile main body and is used for collecting the ore pile image and delineating the block size profile. The method comprises: Turning on the illumination unit to supplement the light and determining the block size analysis area; Pressing the analysis button to automatically focus the photographing unit and synchronously turn on the optical distance measuring unit to adjust the position of the quadrilateral vertexes; Pressing the analysis button again to complete the image collection and distance measurement; Based on the distance of the quadrilateral vertexes measured by the optical distance measuring unit and the included angle between the optical distance measuring units, the length of the side of the quadrilateral, the length of the diagonal and the vertical distance between the device and the ore pile observation plane are calculated. The rock profile circle in the ore pile image collected by the photographing unit is projected into the quadrilateral identification area, and a plane screen grid is constructed in combination with the diagonal line of the quadrilateral and the vertical line of another vertex corresponding to the diagonal line. The maximum closed circle plane area formed by the grid lines intersecting the rock profile line is defined as the minimum grid area S1 of the rock screen, and the plane area formed by extending one circle of grid outward from S1 is defined as the maximum grid area S2 of the rock screen. The interval range of the ore block size is determined by an equivalent block size particle diameter analysis method.

2. A mobile in-mine blast fragmentation analysis method according to claim 1, characterised in that, After the rock profile circle in the ore pile image collected by the photographing unit is projected into the quadrilateral identification area, data processing is performed to obtain the block size data, which further comprises: Performing rock edge detection on the identification area and the surrounding ore pile to delineate the plane closed circle of each rock block size and form a rock block size closed circle composite graph.

3. The mobile in-mine blasting ore fragmentation analysis method of claim 1, wherein, The equivalent block size particle diameter analysis method is as follows: If the length-width ratio of the rock profile circle is greater than or equal to 2.5, the block size particle diameter range is taken as the grid width corresponding to S1 and S2. If the rock profile ring length-width ratio is less than 2.5, the ore block size particle size range is between and .

4. The mobile in-mine blasting ore fragmentation analysis method of claim 1, wherein, After the interval range of the ore block size is determined by the equivalent block size particle diameter analysis method, the underground blasting ore block size analysis method further comprises: Taking another diagonal line of the quadrilateral as a reference, repeating the grid construction process, identifying and counting the ore block size distribution interval intersecting the first diagonal line, and including it in the block size analysis result.

5. The mobile in-mine blasting ore fragmentation analysis method of claim 1, wherein, In the process of pressing the analysis button again to complete the image collection and distance measurement, it further comprises: Taking multiple photographs of the same ore pile at different angles, and accumulating the block size frequency and frequency of each analysis according to the preset block size interval.

6. A mobile in-mine blast fragmentation analysis method according to claim 5, characterised in that, In the process of pressing the analysis button again to complete the image collection and distance measurement, it further comprises: Taking multiple photographs of the surface block size of the same stope ore pile after loading at different time periods, and accumulating the block size frequency and frequency of each analysis according to the preset block size interval.

7. The mobile in-mine blasting ore fragmentation analysis method of claim 1, wherein, After data processing and obtaining the block size data, the underground blasting ore block size analysis method further comprises: Outputting the block size data, wherein the block size data comprises the median block size, the average block size and the 80% screening size; the output form comprises the frequency distribution histogram and the frequency cumulative distribution graph.

Images