Disc pelletizer green pellet size monitoring device and method based on point cloud data processing

Abstract

The invention relates to a disc pelletizer green pellet size monitoring device and method based on point cloud data processing. The device comprises a laser radar, a point cloud data processing terminal computer, a production control server and a green pellet production control HMI. According to the method, the laser radar is additionally arranged at the discharging port below the pelletizing disc and used for monitoring the diameter of the green pellets at the outlet, the qualified rate of the finished green pellets is counted by comparing the diameter with the set pellet diameter, and real-time three-dimensional information of the discharging port replaces manual observation to participate in pelletizing production process control; and the point cloud data processing terminal computer counts the qualified rate in different time periods according to the three-dimensional information, and uploads the processing result to the green pellet production control HMI in real time, so that the system has the characteristics of quick response and high accuracy, and meanwhile, the unmanned production is further realized.

Description

Technical Field

[0001] This patent application belongs to the field of information technology, and more specifically, it relates to a device and method for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing. Background Art

[0002] Pelletizing is a man-made block raw material, which is the process of transforming powdered materials into physical properties and chemical compositions that can meet the requirements of the next processing step. During the pelletizing process, the material not only undergoes changes in physical properties such as density, porosity, shape, size and mechanical strength due to rolling into balls and particle density, but more importantly, chemical changes occur. Pelletizing is to mix finely ground iron ore concentrate or other iron-containing powder with a small amount of additives, and then roll it into balls through a pelletizing machine under the condition of adding water and wetting, and then dry and roast it to consolidate it into a spherical iron-containing raw material with certain strength and metallurgical properties.

[0003] The current method for testing the qualified rate of raw balls is as follows: after the raw balls are screened by the screening equipment, the raw balls of different particle sizes are transported to the target equipment through their respective conveyor belts. During the transmission process, each conveyor belt uses a belt scale and other load-bearing measuring equipment to obtain the mass of raw balls of different particle sizes. The mass of raw balls of qualified particle sizes within the calculation period is divided by the total mass of raw ball production to obtain the qualified rate of raw balls. This method is limited by the working principle of the belt weighing equipment and the influence of the actual production environment, and has low accuracy and poor real-time effect.

[0004] Therefore, a new method / device is needed to improve the accuracy and production efficiency of ball production monitoring. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a device and method for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing, which utilizes the real-time three-dimensional information of the discharge port below the ball making disc to replace manual observation to participate in the process control of ball making production. The system issues alarm information based on the three-dimensional information, and has the characteristics of rapid response and high accuracy, while further realizing unmanned production.

[0006] In order to solve the above problems, the technical solution adopted by the present invention is:

[0007] A device for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing comprises a laser radar arranged below a ball making disc, wherein the scanning angle of the laser radar is adjustable; the probe of the laser radar is aimed at the unloading outlet of the ball making disc, the laser radar is connected to a point cloud data processing terminal computer via a communication cable to transmit the scanned point cloud data, the point cloud data processing terminal computer is connected to a production control server via an industrial WiFi communication device, and the production control server is connected to a raw ball production control HMI, so that the statistical value of the qualified rate is uploaded in real time and displayed on the raw ball production control HMI.

[0008] Furthermore, the laser radar is a multi-line laser radar, which is arranged under the pelletizing disk through an equipment mounting bracket. The base elevation of the equipment mounting bracket is consistent with the base elevation of the pelletizing disk. The connection between the multi-line laser radar and the equipment mounting bracket is configured so that the radar can be adjusted in horizontal and vertical directions and can be reliably fixed.

[0009] A method for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing, using the above device, specifically comprises the following steps:

[0010] S1. On-site layout of the laser radar, determine the installation height H1, vertical radiation angle α, and set angular resolution β of the laser radar;

[0011] S2, laser radar point cloud data acquisition;

[0012] S3, LiDAR point cloud data preprocessing;

[0013] S4, LiDAR point cloud data segmentation;

[0014] S5, lidar point cloud data registration;

[0015] S6, pre-compression of laser radar point cloud data;

[0016] S7, data processing, point cloud data processing terminal computer calculates the particle size qualification rate Y of the periodic spherical particles Q , and the results are output to the raw ball production control HMI.

[0017] Furthermore, in S1, the calculation formula for the installation height H1 is:

[0018]

[0019] Among them, H2 is the height of the ball transmission belt to the ground, in m; H3 is the height of the ball-making disk outlet to the transmission belt, in m; L is the horizontal distance between the laser radar and the ball-making disk, and α is the vertical radiation angle of the laser radar.

[0020] Furthermore, the calculation formula of the horizontal distance L between the laser radar and the ball-making disk is:

[0021]

[0022] Where x is the target particle size of the biosphere, N is the number of point cloud points required to be evenly distributed on the surface of a single biosphere, and β is the set angular resolution of the lidar.

[0023] Furthermore, in S7, the qualified rate of the raw ball particle size Y Q The calculation formula is:

[0024]

[0025] where Y R is the actual qualified count value of the particle size of the generated balls within the period, H is the total number of the generated balls within the period, and Y Q The value is displayed on the raw ball production control HMI. Q <Y r When the ball production control HMI issues an alarm message, L r is the target value required for green ball production, Y r It is the target qualified rate of green ball particle size.

[0026] Furthermore, the actual qualified count value Y of the particle size of the raw ball within the period R The calculation formula is:

[0027]

[0028] Where L ΣQ is the actual measured value of the raw ball particle size, L r The target value required for green ball production.

[0029] Furthermore, the actual measured value of the green ball particle size L ΣQ The calculation formula is:

[0030]

[0031] Where L i is the return value of a single laser radar measurement, and N is the number of point cloud points uniformly distributed on the surface of a single sphere;

[0032] L i The calculation formula is:

[0033]

[0034] Where L c is the laser radar measurement value each time, and β is the set angular resolution of the laser radar.

[0035] Furthermore, the target qualified rate of green ball particle size Y r The calculation formula is:

[0036]

[0037] Where T is the statistical time, unit: min;

[0038] T P is the daily production target, unit: t / d;

[0039] dfp is the production output set by the equipment, unit: t / min.

[0040] Due to the adoption of the above technical solution, the beneficial effects achieved by the present invention are:

[0041] The device and method for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing of the present invention installs a laser radar (preferably a multi-line laser radar) at the discharge port below the ball making disc to measure the diameter of the raw balls at the outlet in real time, and outputs matching statistical information by comparison with the set size, thereby obtaining the raw ball production qualification rate. The raw ball size monitoring system and the ball making production control system are integrated into one system. The system obtains a real-time report on the raw ball qualification rate, compares the actual qualification rate within a fixed period with the expected qualification rate, and sends a production alarm signal to the operator when it is lower than the warning value, thereby realizing online statistics of the raw ball particle size data, and responding quickly and accurately.

[0042] The method uses the real-time three-dimensional information of the discharge port below the pelletizing disk to replace manual observation to participate in the process control of pelletizing production. The integrated control system issues alarm information based on the three-dimensional information, which has the characteristics of rapid response and high accuracy. At the same time, it further realizes the unmanned detection of the qualified rate of raw ball particle size, ensuring the unmanned production with a high degree of intelligence. After implementation, the operation is stable and reliable, the operation and maintenance are convenient, the working time and work intensity of the staff are reduced, and the accident rate is reduced while improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a structural diagram of the system in the present invention;

[0044] Figure 2 It is a data processing flow chart of the method of the present invention;

[0045] Figure 3 It is the schematic diagram of radar algorithm;

[0046] Figure 4 It is the schematic diagram of the equipment on-site layout;

[0047] Figure 5 It is the final output result image after segmentation, registration, and pre-compression;

[0048] Figure 6 It is an example result diagram of the present invention.

[0049] Among them: 1. Laser radar, 2. Point cloud data processing terminal computer, 3. Production control server, 4. Ball production control HMI, 5. Ball making disk, 6. Conveyor belt. DETAILED DESCRIPTION

[0050] The present invention is further described in detail below with reference to the embodiments.

[0051] A device and method for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing, such as Figure 1The system structure consists of: laser radar 1, point cloud data processing terminal computer 2, and raw ball production control HMI 4. The laser radar 1 is arranged below the ball making disk 5 and is connected to the point cloud data processing terminal computer 2 through a communication cable to transmit the scanned point cloud data. The probe of the laser radar 1 is aimed at the unloading outlet of the ball making disk 5, and the scanning angle of the laser radar 1 is adjustable. The point cloud data processing terminal computer 2 is connected to the production control server 3 through an industrial WiFi communication device, and the production control server 3 is connected to the raw ball production control HMI 4, so that the qualified rate statistics are displayed on the raw ball production control HMI 4.

[0052] In terms of equipment selection, the laser radar 1 is a multi-line laser radar, which is arranged below the pelletizing disk 5 through an equipment mounting bracket. The base elevation of the equipment mounting bracket is consistent with the base elevation of the pelletizing disk 5. The connection between the multi-line laser radar and the equipment mounting bracket is set so that the radar can be adjusted in the horizontal and vertical directions and can be reliably fixed.

[0053] like Figure 2 The data processing flow of the point cloud data processing of the system shown in the figure for monitoring the size of raw balls of the disc ball making machine is as follows:

[0054] S1. Layout of laser radar on site: determine the installation height H1, vertical radiation angle α, and set angular resolution β of the laser radar.

[0055] The laser radar 1 is preferably a multi-line laser radar, and the multi-line laser radar, equipment installation bracket, radar power supply, power supply cable and communication cable constitute the raw ball particle size detection equipment. The base elevation of the above-mentioned equipment installation bracket is consistent with the base elevation of the ball making disk 5. The bracket height can support the installation height of the multi-line laser radar to be level with the feed port. The connection between the multi-line laser radar and the equipment installation bracket is set to be adjustable in the horizontal and vertical directions of the radar and can be reliably fixed. The installation position of the base of the equipment installation bracket is adjusted according to the vertical distance from the outlet of the ball making disk 5 to the raw ball conveyor belt 6 on site, in order to ensure that the multi-line laser radar scanning angle is fully utilized.

[0056] The multi-line laser radar is arranged below the pelletizing disk 5, and the probe is aimed at the discharge outlet of the pelletizing disk 5. The multi-line laser radar is used to scan the particle size of the raw balls. The point cloud data obtained by scanning is sent to the point cloud data processing terminal computer 2. The point cloud data processing terminal computer 2 processes the data and uploads the processing result data to the raw ball production control HMI 4 in real time.

[0057] In S1, the calculation formula for the installation height H1 is:

[0058]

[0059] Among them, H2 is the height of the ball transmission belt above the ground in m, H3 is the height of the discharge port of the ball making disk 5 to the transmission belt 6 in m, L is the horizontal distance between the laser radar and the ball making disk 5, and α is the vertical radiation angle of the laser radar.

[0060] The calculation formula of the horizontal distance L between the laser radar and the ball-making disk is:

[0061]

[0062] Where x is the target particle size of the biosphere, N is the number of point cloud points required to be evenly distributed on the surface of a single biosphere, and β is the angular resolution of the laser radar.

[0063] S2. Acquisition of laser radar point cloud data. The details of point cloud data acquisition are as follows:

[0064] var serverIp="192.168.0.59";

[0065] var port = 2112;

[0066] var messageToSend="02 73 52 4E 20 4C 4D 44 73 63 61 6E 64 61 74 6103";

[0067] The connection port should select the correct port number according to the device settings. In this case, the port number is 2112. At the same time, the instruction used to obtain data should be to obtain the word scanning results to facilitate subsequent data processing. The device instruction used in this case is: "02 7352 4E 20 4C 4D 44 73 63 61 6E 64 61 74 61 03".

[0068] S3. LiDAR point cloud data preprocessing.

[0069] The details of point cloud data processing are shown in the following code.

[0070]

[0071]

[0072] In the above data analysis process, the analysis parameters should be set according to the specific situation of the equipment. In this case, the equipment multiplier factor used is: "40000000". In this case, the equipment angle resolution factor used is: (parts

[25] , 16), and the angle resolution multiplier factor is set to: "1000".

[0073] S4. LiDAR point cloud data segmentation.

[0074] S5. LiDAR point cloud data registration.

[0075] S6. Pre-compression of LiDAR point cloud data.

[0076] The final output of the LiDAR point cloud data after segmentation, registration, and pre-compression is as follows Figure 5 As shown, Figure 5 The data in the last row on the left and right sides are not fully displayed because of the scroll bar. You can ignore it or not use it as a reference.

[0077] S7, data processing, result output. The output result is the actual particle size value and number of raw balls within the measurement time, so as to obtain the actual proportion of qualified particle size, that is, the qualified rate of raw ball particle size within the period Y Q , the qualified rate of the particle size of the raw ball in the period Y Q The target value L required for green ball production r When the value is lower than the target value required for raw ball production, an alarm message will be displayed on the raw ball production control HMI 4.

[0078] The qualified rate of particle size of the periodic spheres Y Q The calculation formula is:

[0079]

[0080] where Y R is the actual qualified count value of the particle size of the generated balls within the period, H is the total number of the generated balls within the period, and Y Q The value is displayed on the green ball production control HMI 4, and when Y Q <Y r When the ball production control HMI 4 issues an alarm message, L r The target value required for green ball production.

[0081] The actual qualified count value Y of the particle size of the raw ball within the period R The calculation formula is:

[0082]

[0083] Where L ∑Q is the actual measured value of the raw ball particle size, L r The target value required for green ball production.

[0084] Actual measured value of green ball particle size L ∑Q The calculation formula is:

[0085]

[0086] Where L i is the return value of a single laser radar measurement, and N is the number of point cloud points uniformly distributed on the surface of a single sphere;

[0087] Li The calculation formula is:

[0088]

[0089] Where L c is the laser radar measurement value each time, and β is the angular resolution of the laser radar.

[0090] Green ball particle size target qualified rate Y r The calculation formula is:

[0091]

[0092] Where T is the statistical time, unit: min;

[0093] T P is the daily production target, unit: t / d;

[0094] dfp is the production output set by the equipment, unit: t / min.

[0095] like Figure 3 The schematic diagram of calculating particle size value from LiDAR point cloud data is shown. Figure 4 This is the schematic diagram of the equipment on-site layout. i is the single measurement return value of the laser radar. According to the point cloud filtering and measurement accuracy requirements, L i The number of is set to 5, and the angular resolution of the laser radar is set to 0.05°.

[0096] According to formula ②, where x=12mm, n=5, β=0.05, the horizontal distance L between the laser radar and the ball-making disk 5 is calculated to be 2.75m. According to the on-site process installation requirements, the height unit of the ball-making transmission belt to the ground is H2=0.8m, and the height of the discharge port of the ball-making disk 5 to the conveyor belt 6 is H3=1.2m. According to formula ①, the laser radar equipment selection requirement is that the vertical radiation angle α ≥ 25.12°, thereby obtaining the equipment selection parameters and equipment installation parameters.

[0097] According to formula ④⑤⑥, calculate the actual qualified count value Y of the green ball particle size R , calculate the target qualified rate Y of green ball particle size according to formula ⑦ r , according to formula ③, calculate the qualified rate Y of the particle size of the raw ball within the cycle Q , Y Q The value is displayed on the production control HMI. Q <Y r The production control HMI issues an alarm message.

[0098] The example results of formula ③④⑤⑥⑦ are as follows Figure 6 As shown, Figure 6 The difference between the continuous segments is the calculated value of the method of the present invention. Figure 6 The unit of the value is meter. Negative number means the measurement is in the left area of ​​the equipment, positive number means the measurement is in the right area of ​​the equipment. When calculating the qualified rate, the absolute value of the calculated value is substituted into the formula, then the formula ⑦ calculates the qualified rate of raw ball particle size target Y r =100%×number of qualified calculated values÷total number of calculated values, case calculation result Y r =About 76.5%.

Claims

1. A device for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing, characterized in that: The invention comprises a laser radar (1) arranged below a pelletizing disk (5), wherein the scanning angle of the laser radar (1) is adjustable; the probe of the laser radar (1) is aimed at the material discharge outlet of the pelletizing disk (5); the laser radar (1) is connected to a point cloud data processing terminal computer (2) via a communication cable to transmit scanned point cloud data; the point cloud data processing terminal computer (2) is connected to a production control server (3) via an industrial WiFi communication device; the production control server (3) is connected to a pelletizing production control HMI (4), thereby uploading and displaying the qualified rate statistics in real time on the pelletizing production control HMI (4).

2. The device for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing according to claim 1 is characterized in that: The laser radar (1) is a multi-line laser radar, which is arranged below the pelletizing disk (5) through an equipment mounting bracket. The base elevation of the equipment mounting bracket is consistent with the base elevation of the pelletizing disk (5). The connection between the multi-line laser radar and the equipment mounting bracket is arranged so that the radar horizontal and vertical angles can be adjusted and can be reliably fixed.

3. A method for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing, using the device described in claim 1, characterized in that The steps include: S1. On-site layout of the laser radar, determine the installation height H1, vertical radiation angle α, and set angular resolution β of the laser radar; S2, laser radar point cloud data acquisition; S3, LiDAR point cloud data preprocessing; S4, LiDAR point cloud data segmentation; S5, lidar point cloud data registration; S6, pre-compression of laser radar point cloud data; S7, data processing, point cloud data processing terminal computer (2) calculates the qualified rate Y of the particle size of the periodic sphere Q The results are output to the pellet production control HMI (4).

4. The method for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing according to claim 3 is characterized in that: In S1, the calculation formula for the installation height H1 is: Wherein H2 is the height of the ball-forming conveying belt to the ground, in m; H3 is the height of the discharge port of the ball-forming disk (5) to the conveying belt (6), in m; L is the horizontal distance between the laser radar and the ball-forming disk (5), and α is the vertical radiation angle of the laser radar.

5. The method for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing according to claim 4 is characterized in that: The calculation formula of the horizontal distance L between the laser radar and the ball-making disk (5) is: Where x is the target particle size of the biosphere, N is the number of point cloud points required to be evenly distributed on the surface of a single biosphere, and β is the set angular resolution of the lidar.

6. The method for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing according to claim 5 is characterized in that: In S7, the qualified rate of raw ball particle size within the cycle is Y Q The calculation formula is: where Y R is the actual qualified count value of the particle size of the generated balls within the period, H is the total number of the generated balls within the period, and Y Q The value is displayed on the green ball production control HMI (4), and when Y Q <Y r When the ball production control HMI (4) issues an alarm message, L r is the target value required for green ball production, Y r It is the target qualified rate of green ball particle size.

7. The method for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing according to claim 6 is characterized in that: The actual qualified count value Y of the particle size of the raw ball within the period R The calculation formula is: Where L ΣQ is the actual measured value of the raw ball particle size, L r The target value required for green ball production.

8. The method for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing according to claim 7 is characterized in that: Actual measured value of green ball particle size L ΣQ The calculation formula is: Where L i is the return value of a single laser radar measurement, and N is the number of point cloud points uniformly distributed on the surface of a single sphere; L i The calculation formula is: Where L c is the laser radar measurement value each time, and β is the set angular resolution of the laser radar.

9. The method for monitoring the size of raw balls of a disc ball making machine based on point cloud data processing according to claim 6, characterized in that: Green ball particle size target qualified rate Y r The calculation formula is: Where T is the statistical time, unit: min; T P is the daily production target, unit: t / d; dfp is the production output set by the equipment, unit: t / min.

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