Self-calibration bale nozzle visual opening detection system and method

Abstract

The invention discloses a self-calibration large ladle nozzle visual opening degree detection system and method, and the system comprises an image collection unit which is used for collecting an image of a large ladle long nozzle position; the image processing unit is used for acquiring the image information sent by the image acquisition unit in real time, automatically performing target identification on the image of the large-ladle long nozzle, and detecting and recording the current position coordinates of the large-ladle long nozzle in real time; the automatic calibration unit is used for acquiring and recording a pressure signal of the large-ladle long nozzle, screening and determining a zero coordinate of the large-ladle long nozzle, and determining an opening range of the large-ladle long nozzle; and the calculation output unit is used for calculating and obtaining the opening value of the large ladle long nozzle according to the position coordinate, the zero coordinate and the opening range of the large ladle long nozzle. The detection precision and reliability of the continuous casting bale nozzle visual opening degree detection system are improved, and the problem that the precision fluctuation is large in an existing visual detection technology is solved.

Description

Technical Field

[0001] This invention relates to continuous casting production process inspection technology, and more specifically, to a self-calibrated ladle nozzle visual opening detection system and method. Background Technology

[0002] In the continuous casting production process, the ladle opening is a crucial means of controlling the amount of molten steel flowing out of the ladle, directly affecting the molten steel level in the tundish and the stability of continuous casting production and quality. With the development of machine vision technology, a newly developed detection technology has emerged in recent years: using cameras to capture images of the long nozzle connected to the sliding gate at the bottom of the ladle, and then using intelligent image analysis to identify changes in the position of the long nozzle, thereby calculating and determining the corresponding changes in the ladle sliding gate opening. This technology offers advantages such as remote, non-contact operation, low failure rate, and low maintenance. However, it has a drawback: the detection accuracy fluctuates considerably.

[0003] The reason for the large fluctuations in detection accuracy is:

[0004] 1) In the continuous casting unit, the ladle turret that carries the ladle needs to be rotated 180 degrees when changing the ladle for pouring. After each rotation and positioning, there will be a certain degree of deviation in the positioning accuracy of the ladle, which will cause the initial position of the sliding gate at the bottom of the ladle in the pouring position to be uncertain for different heats.

[0005] 2) The long nozzle of the ladle is connected to the sliding nozzle at the bottom of the ladle via a lifting device before pouring. Before the long nozzle is lifted and connected to the ladle for pouring, it may tilt or have its angle adjusted, which will cause the initial installation position of the long nozzle to change in different batches. All of these factors will cause the initial zero position of the long nozzle of the ladle before pouring to be different in different batches. If the position is not corrected by calibration, it will lead to serious detection errors, resulting in incorrect detection and control results and affecting the normal use of the system.

[0006] Currently, there is no good solution for the detection position correction of this type of system. Calibration is mainly done manually. Specifically, after each ladle rotation and positioning on the turntable, a person manually presses the zero-position calibration button before pouring begins, sending a calibration signal to the system, which then calibrates the zero position of the ladle nozzle. This method is prone to errors or omissions in the timing of manual button presses, leading to fluctuations in detection accuracy and making it difficult to achieve stable and accurate monitoring and control. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the purpose of this invention is to provide a self-calibrated visual opening detection system and method for ladle nozzles, thereby improving the detection accuracy and reliability of continuous casting ladle nozzle visual opening detection systems and solving the problem of large accuracy fluctuations in current visual inspection technologies.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] The first aspect of this invention provides a self-calibrating visual opening detection system for large-mass injection nozzles, comprising:

[0010] Image acquisition unit, used to acquire images of the location of the long sprue inlet of the large package;

[0011] The image processing unit is used to acquire image information emitted by the image acquisition unit in real time, automatically perform target recognition on the image of the large package long sprue, and detect and record the current position coordinates of the large package long sprue in real time.

[0012] The automatic calibration unit acquires and records the pressure signal of the large package long nozzle, filters and determines the zero position coordinate of the large package long nozzle, and also determines the opening range of the large package long nozzle.

[0013] The calculation output unit calculates and obtains the opening value of the long water inlet of the large package based on the position coordinates, zero position coordinates and opening range of the long water inlet.

[0014] Preferably, the image acquisition unit includes:

[0015] The industrial camera, which is a network camera with a high-definition lens, is used to capture images of the pouring area on the long nozzle of the large ladle in real time and send the image signal to the image processing unit.

[0016] A protective cover, employing a water-air composite cooling protective cover, is installed on the outside of the industrial camera to protect it.

[0017] The pan-tilt bracket uses a three-dimensional adjustable pan-tilt head, which is connected to the industrial camera to adjust the angle and position of the industrial camera.

[0018] Preferably, the automatic calibration unit includes:

[0019] The signal monitoring module is used to start and stop the zero-position data acquisition of the large package long water inlet;

[0020] The data recording module continuously acquires the position coordinates of the large package long nozzle from the image processing unit according to the zero-position acquisition start signal sent by the signal monitoring module, and records them in the zero-position data queue; at the same time, it stops updating the zero-position data queue according to the zero-position acquisition stop signal sent by the signal monitoring module.

[0021] The zero-position filtering module is used to filter out reliable zero-position frames of the large package long nozzle image from the zero-position data queue recorded by the data recording module, and determine the zero-position coordinates of the large package long nozzle.

[0022] The range prediction module is used to determine the opening range of the long nozzle of the large package in advance based on the difference between the fully open position coordinates and the fully closed position coordinates of the sliding nozzle of the large package.

[0023] Preferably, the signal monitoring module includes:

[0024] The zero-position acquisition start signal monitoring module uses a pressure sensor and is installed on the lifting air path of the long water inlet of the large package. When the pressure detection value exceeds the set threshold, the long water inlet of the large package is in the tightened state, and a zero-position acquisition start signal is sent to the data recording module.

[0025] The zero-position acquisition stop signal monitoring module establishes data communication with the large package sliding gate control system, receives the gate opening signal from the large package sliding gate control system to indicate the opening state of the large package sliding gate, and sends a zero-position acquisition stop signal to the data recording module.

[0026] The second aspect of this invention provides a self-calibrated visual opening detection method for large-mass injection nozzles, employing the self-calibrated visual opening detection system for large-mass injection nozzles provided in the first aspect of this invention, and performing the following steps:

[0027] S1, The image acquisition unit acquires images of the pouring area on the long nozzle of the large package in real time;

[0028] S2, after the large ladle is rotated to the pouring position, the image processing unit identifies and detects the image of the pouring area on the long nozzle of the large ladle, and records the position coordinates P of the long nozzle of the large ladle corresponding to each frame of the image in real time;

[0029] S3, by monitoring the tightening signal of the large package long nozzle, the automatic calibration unit is triggered to start zero-position data acquisition and record it to the zero-position data queue;

[0030] S4, by triggering the opening signal of the sliding nozzle of the large bag when the large bag starts pouring, the automatic calibration unit is triggered to stop zero-position data acquisition, and the zero-position frame is selected from the data queue to automatically complete the update calibration of the zero-position coordinate P0 of the long nozzle of the large bag.

[0031] S5, based on the zero-position coordinate P0 of the large package long water nozzle and the opening range P of the large package long water nozzle. S The location coordinates P of the large package long sprue nozzle are used to determine the opening value G of the large package long sprue nozzle through the calculation output unit, i.e., G = (P - P0) / P. S *100%.

[0032] Preferably, step S3 specifically includes the following steps:

[0033] S31, the zero-position acquisition start signal monitoring module is installed on the lifting air path of the large package long water inlet, and the monitoring signal of the zero-position acquisition start signal monitoring module is sent to the automatic calibration unit.

[0034] S32, when the long water inlet of the large package rises and presses against the sliding water inlet of the large package, the pressure signal in the lifting air path of the long water inlet of the large package exceeds the set threshold, and a pressing detection signal of the long water inlet of the large package is issued.

[0035] S33, upon receiving the top-tightening detection signal, the automatic calibration unit sets the zero-position data acquisition flag and begins to continuously acquire the position coordinate data of the long water inlet of the large package from the image processing unit, and records and saves it to the zero-position data queue.

[0036] Preferably, in step S33, the zero-position data queue is a collection of candidate zero-position coordinate data of the large-capacity water inlet collected and arranged in a first-in-first-out manner according to a set frame scanning interval period.

[0037] Preferably, step S4 specifically includes the following steps:

[0038] S41, when the automatic calibration unit receives the signal that the sliding gate of the ladle is opened when the ladle is started to pour, it automatically resets the zero-position data acquisition flag and stops the acquisition and update of the zero-position data queue.

[0039] S42, calculate the rate of change of the water inlet position in adjacent frames sequentially from back to front along the zero-position data queue, V i =(D i -D i-1 ) / T;

[0040] Let the zero-point data queue be [D1, D2, ..., D when zero-point data acquisition stops.] i D n-1 D n ], D n D is the coordinate of the last water inlet position recorded when zero-position data acquisition stops. n-1 D represents the coordinates of the sprue position in the previous frame. i Let be the coordinates of the water inlet position in the i-th frame, and T be the frame scanning interval;

[0041] S43, after each calculation, determine the rate of change V of the water inlet position. i If the position change rate is lower than the minimum water inlet switching rate, then determine the next frame of the adjacent frame as the zero position frame; otherwise, return to step S42 to continue calculating the position change rate of the previous pair of adjacent frames.

[0042] S44, perform a confidence judgment on the position coordinates of the zero-position frame. If it is within the zero-position confidence interval, it is adopted, updated, and transmitted to the zero-position coordinate P0 of the large package long water inlet. If it is outside the zero-position confidence interval, it is not adopted and updated.

[0043] Preferably, in step S44, the zero position information interval of the large package is determined by statistically analyzing the distribution interval of the change in the position coordinates of the long nozzle image when the large package is rotated to the pouring position.

[0044] Preferably, in step S5, the opening range P of the large package long nozzle is... S It is achieved by recording and calculating the corresponding gate position coordinate P when the sliding gate of the large package is fully open. opn The coordinates P of the water inlet position when it is fully closed. cls The difference is used to determine P. S =P opn -P cls .

[0045] The present invention provides a self-calibrating ladle nozzle visual opening detection system and method that can automatically calibrate the ladle nozzle zero position without human intervention. This significantly improves the accuracy and reliability of ladle nozzle visual opening detection, effectively solving the problems of current detection systems requiring manual intervention, large accuracy fluctuations, and unreliable accuracy. This ensures that ladle nozzle visual opening detection technology can be accurately and reliably used for production anomaly monitoring and early warning, and improves the intelligent monitoring level of steelmaking continuous casting production lines. Attached Figure Description

[0046] Figure 1 This is a schematic diagram of the structural framework of the visual opening degree detection system for the large-capacity sprue of the present invention;

[0047] Figure 2 This is a flowchart illustrating the visual opening detection method for the large-capacity sprue nozzle of the present invention.

[0048] Figure 3 This is a flowchart illustrating step S3 in the visual opening detection method for large-package sprue nozzles of the present invention.

[0049] Figure 4 This is a flowchart illustrating step S4 in the visual opening detection method for the large-capacity sprue of the present invention. Detailed Implementation

[0050] To better understand the above-mentioned technical solutions of the present invention, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0051] Combination Figure 1 As shown, the present invention provides a self-calibrating visual opening detection system for large-scale sprue nozzles, comprising:

[0052] Image acquisition unit 1 is used to acquire images of the location of the long water inlet 5 of the large package;

[0053] Image processing unit 2 is used to acquire image information emitted by image acquisition unit 1 in real time, automatically perform target recognition on the image of the large package long sprue 5, and detect and record the current position coordinates P of the large package long sprue 5 in real time;

[0054] Automatic calibration unit 3 acquires and records the pressure signal of the main tank nozzle 5, and filters and determines the zero-position coordinate P0 of the main tank nozzle 5, while also determining the opening range P of the main tank nozzle 5. S ;

[0055] Calculate output unit 4 based on the position coordinates P of the large package long water inlet 5, the zero position coordinate P0, and the opening range P. S Calculate and obtain the opening value G of the large package long water inlet 5.

[0056] Image acquisition unit 1 includes:

[0057] The industrial camera, a network camera with a high-definition lens, is used to capture images of the pouring area on the long nozzle 5 of the large package in real time, and send the image signal to the image processing unit 2.

[0058] The protective cover, which is a water-air composite cooling protective cover, is located on the outside of the industrial camera. It can simultaneously allow water and air to pass through, so as to protect the industrial camera from the effects of dust, splashes and high temperature environments.

[0059] The pan-tilt bracket uses a three-dimensional adjustable pan-tilt head, which is connected to the industrial camera to adjust the angle and position of the industrial camera when acquiring images.

[0060] The image processing unit 2 consists of an industrial control computer, which has a central processing unit, memory, and network interface.

[0061] Automatic calibration unit 3 includes:

[0062] Signal monitoring module 31 is used to start and stop the zero-position data acquisition of the large package long water inlet 5;

[0063] The data recording module 32 continuously acquires the position coordinates of the large package long water inlet 5 from the image processing unit 2 according to the zero-position acquisition start signal sent by the signal monitoring module 31, and records them into the zero-position data queue; at the same time, it stops updating the zero-position data queue according to the zero-position acquisition stop signal sent by the signal monitoring module 31.

[0064] The zero-position filtering module 33 is used to filter out the reliable zero-position frames of the large package long nozzle image from the zero-position data queue recorded by the data recording module 32, and determine the zero-position coordinates P0 of the large package long nozzle 5.

[0065] The range prediction module 34 is used to pre-determine the fully open position coordinate P of the sliding gate 6 of the package. opn and the coordinates of the full position P cls The difference between them is used to determine the opening range P of the large package long nozzle 5. S P S =P opn -P cls .

[0066] Signal monitoring module 31 includes:

[0067] The zero-position acquisition start signal monitoring module 311 uses a pressure sensor and is installed on the lifting air path of the long water inlet 5 of the large package. When the pressure detection value exceeds the set threshold, it is reflected as the tight state of the long water inlet 5 of the large package, and a zero-position acquisition start signal is sent to the data recording module 32.

[0068] The zero-position acquisition stop signal monitoring module establishes data communication with the large package sliding nozzle control system 7. It receives the nozzle opening signal from the large package sliding nozzle control system 7, which is reflected as the opening state of the large package sliding nozzle 6, and sends a zero-position acquisition stop signal to the data recording module 32.

[0069] The calculation output unit 4 is used to calculate the zero coordinate P0 of the automatically updated and calibrated large package long nozzle 5 and the opening range P of the large package long nozzle 5. S The position coordinates P of the large-bag long sprue 5 obtained from the image processing unit 2 are used to calculate the opening value G of the large-bag long sprue 5, where G = (P - P0) / P. S *100%.

[0070] Combination Figure 1 and Figure 2 As shown, the present invention also provides a self-calibrated visual opening detection method for large-mast nozzles. Using the self-calibrated visual opening detection system of the present invention, the following steps are performed:

[0071] S1, the image of the pouring area on the long nozzle 5 of the large package is acquired in real time through the image acquisition unit 1;

[0072] S2, after the large ladle 8 is rotated to the pouring position, the image processing unit 2 identifies and detects the image of the pouring area on the long nozzle 5 of the large ladle, and records the position coordinates P of the long nozzle 5 of the large ladle corresponding to each frame of the image in real time.

[0073] S3, by monitoring the tightening signal of the long nozzle 5 of the large package, triggers the automatic calibration unit 3 to start zero-position data acquisition and records it to the zero-position data queue;

[0074] S4, by triggering the opening signal of the sliding nozzle 6 of the large sluice bag 8 when the pouring begins, the automatic calibration unit 3 is triggered to stop zero-position data acquisition, and the zero-position frame is selected from the data queue to automatically complete the update and calibration of the zero-position coordinate P0 of the long nozzle 5 of the large sluice bag.

[0075] S5, based on the zero coordinate P0 of the long water inlet 5 of the large package, and the opening range P of the long water inlet 5 of the large package. S The position coordinates P of the long sprue nozzle 5 are used to determine the opening value G of the long sprue nozzle 5 through the calculation output unit 4, i.e., G = (P - P0) / P S *100%.

[0076] Combination Figure 3 As shown, step S3 in the visual opening detection method for large-package sprue nozzles of the present invention specifically includes the following steps:

[0077] S31, a zero-position acquisition start signal monitoring module 311 is set on the lifting air path of the large bag long water inlet 5, and the monitoring signal of the zero-position acquisition start signal monitoring module 311 is sent to the automatic calibration unit 3.

[0078] S32, when the long water inlet 5 of the large package rises and presses against the sliding water inlet 6 of the large package, the pressure signal in the lifting air path of the long water inlet 5 of the large package exceeds the set threshold, and a pressing detection signal of the long water inlet 5 of the large package is issued.

[0079] S33, upon receiving the top-tightening detection signal, the automatic calibration unit 3 sets the zero-position data acquisition flag and begins to continuously acquire the position coordinate data of the large package long water inlet 5 from the image processing unit 2, and records and saves it to the zero-position data queue.

[0080] In step S33 above, the zero-position data queue is a collection of candidate zero-position coordinate data of the large-capacity water inlet, which are collected and arranged in a first-in-first-out manner according to a certain frame scanning interval period.

[0081] Combination Figure 4 As shown, step S4 in the visual opening detection method for large-package sprue nozzles of the present invention specifically includes the following steps:

[0082] S41, when the automatic calibration unit 3 receives the signal that the sliding gate 6 of the large ladle 8 is opened when the large ladle 8 is started to pour, it automatically resets the zero-position data acquisition flag and stops the acquisition and update of the zero-position data queue.

[0083] S42, calculate the rate of change of the water inlet position in adjacent frames sequentially from back to front along the zero-position data queue, V i =(D i -D i-1 ) / T;

[0084] Let the zero-point data queue be [D1, D2, ..., D when zero-point data acquisition stops.] iD n-1 D n ], D n D is the coordinate of the last water inlet position recorded when zero-position data acquisition stops. n-1 D represents the coordinates of the sprue position in the previous frame. i Let be the coordinates of the water inlet position in the i-th frame, and T be the frame scanning interval;

[0085] S43, after each calculation, determine the rate of change V of the water inlet position. i If the position change rate is lower than the minimum water inlet switching rate, then determine the next frame of the adjacent frame as the zero position frame; otherwise, return to step S42 to continue calculating the position change rate of the previous pair of adjacent frames.

[0086] S44: Perform a confidence check on the position coordinates of the zero-position frame. If it is within the zero-position confidence interval, it is adopted, updated, and transmitted to the zero-position coordinate P0 of the large packet long water inlet 5. If it is outside the zero-position confidence interval, it is not adopted or updated.

[0087] In step S44 above, the zero position information interval of the large package 8 is determined by statistically analyzing the distribution range of the change in the position coordinates of the long nozzle image when the large package 8 is rotated to the pouring position.

[0088] In step S5 of the visual opening detection method for large package sprue nozzles of the present invention, the opening range P of the long sprue nozzle 5 of the large package is... S It is achieved by recording and calculating the corresponding gate position coordinate P when the large package sliding gate 6 is fully open. opn The coordinates P of the water inlet position when it is fully closed. cls The difference is used to determine P. S =P opn -P cls .

[0089] Since the stroke range of the hydraulic cylinder driving the sliding gate 6 is fixed, the fully open position coordinate P opn and the coordinates of the full position P cls The difference also shows a relatively fixed value, which can be determined by obtaining the position coordinates of the fully open and fully closed nozzles of the large package 8 from the image processing unit 2 through the full stroke action test of the nozzle at the pouring position.

[0090] Example

[0091] This embodiment provides a self-calibrated ladle nozzle visual opening detection system and method for use in the visual opening detection of the ladle nozzle in a round and square billet continuous casting machine, where the rated capacity of the ladle is 150t.

[0092] Combination Figure 1 As shown, the visual opening detection system for the large-capacity water inlet in this embodiment includes an image acquisition unit 1, an image processing unit 2, an automatic calibration unit 3, and a calculation output unit 4.

[0093] Image acquisition unit 1 includes an industrial camera, a protective cover, and a pan-tilt bracket.

[0094] The industrial camera uses a network camera with a high-definition lens to capture images of the pouring area on the long nozzle 5 of the large package in real time, and sends the image signal to the image processing unit 2.

[0095] The protective cover adopts a water-air composite cooling protective cover, and its outer shell can simultaneously allow water and air to pass through, in order to protect industrial cameras from the effects of dust, splashes and high temperature environments.

[0096] The pan-tilt bracket uses a three-dimensional adjustable pan-tilt head, which is used to easily adjust the angle and position of the images captured by the industrial camera.

[0097] In this example, the industrial camera used is an 8-megapixel starlight-level bullet network camera with an Ethernet signal interface.

[0098] Image processing unit 2 is connected to image acquisition unit 1 and is used to receive image information sent by image acquisition unit 1 in real time, automatically identify the target in the image of the large package long sprue 5, and detect and record the current position coordinates P of the large package long sprue 5 in real time.

[0099] In this example, the image processing unit 2 is composed of an industrial control computer, which has a central processing unit, memory, and network interface.

[0100] The automatic calibration unit 3 includes a signal monitoring module 31, a data recording module 32, a zero-point screening module 33, and a range pre-setting module 34.

[0101] The signal monitoring module 31 is used to start and stop zero-position data acquisition, including a zero-position acquisition start signal monitoring module 311 and a zero-position acquisition stop signal monitoring module.

[0102] The zero-position acquisition start signal monitoring module 311 is a pressure sensor installed on the lifting air path of the long water inlet 5 of the large package. When the pressure detection value exceeds the set threshold, it reflects the tightening state of the long water inlet 5 of the large package and sends a zero-position acquisition start signal to the data recording module 32.

[0103] In this example, the pressure sensor is a pressure switch, which is installed on the cylinder intake circuit. The threshold is set to 150 kgf. When the cylinder clamping force exceeds 150 kgf, the pressure switch contacts are closed, and a clamping signal is sent to the main sprue 5.

[0104] The zero-position acquisition stop signal monitoring module includes a water inlet opening signal received from the large package sliding water inlet control system 7, which reflects the opening status of the large package sliding water inlet 6, and sends a zero-position acquisition stop signal to the data recording module 32.

[0105] In this example, the large package sprue visual opening detection system has an Ethernet interface and establishes communication with the large package sliding sprue control system 7 through the TCP / IP protocol. It can obtain the opening signal of the large package sliding sprue 6 through network communication.

[0106] The data recording module 32 is used to continuously collect the position coordinates of the large package long water inlet 5 from the image processing unit 2 according to the zero-position acquisition start signal sent by the signal monitoring module 31, and record them in the zero-position data queue; at the same time, according to the zero-position acquisition stop signal sent by the signal monitoring module 31, it stops the update recording of the zero-position data queue.

[0107] The zero-position filtering module 33 is used to filter out the reliable zero-position frames of the large package long nozzle image from the zero-position data queue recorded by the data recording module 32, and determine the zero-position coordinates P0 of the large package long nozzle 5.

[0108] The range prediction module 34 is used to pre-determine the fully open position coordinate P of the sliding gate 6 of the package. opn and the coordinates of the full position P cls The difference is used to determine the opening range P of the large package long nozzle 5. S =P opn -P cls .

[0109] The calculation output unit 4 is used to calculate the zero coordinate P0 of the automatically updated and calibrated large package long nozzle 5 and the opening range P of the large package long nozzle 5. S The position coordinates P of the large-bag long sprue 5 obtained from the image processing unit 2 are used to calculate the opening value G of the large-bag long sprue 5, where G = (P - P0) / P. S *100%.

[0110] Combination Figure 1 and Figure 2 As shown, the visual opening detection method for the large-capacity sprue nozzle in this embodiment includes the following steps:

[0111] S1, the image of the pouring area on the long nozzle 5 of the large package is acquired in real time through the image acquisition unit 1;

[0112] S2, after the large ladle 8 is rotated to the pouring position, the image processing unit 2 identifies and detects the image of the long nozzle 5 of the large ladle, and records the position coordinates P of the long nozzle 5 of the large ladle corresponding to each frame of the image in real time.

[0113] S3, by monitoring the tightening signal of the long nozzle 5 of the large package, triggers the automatic calibration unit 3 to start zero-position data acquisition and records it to the zero-position data queue;

[0114] S4, by the signal of the opening of the sliding nozzle 6 of the large ladle when the large ladle 8 is poured, the automatic calibration unit 3 is triggered to stop the zero-position data acquisition, and the zero-position frame is selected from the data queue to automatically complete the update and calibration of the zero-position coordinate P0 of the long nozzle 5 of the large ladle.

[0115] S5, based on the automatically updated zero coordinate P0 of the long nozzle 5 of the large package and the opening range P of the long nozzle 5 of the large package. S The position coordinates P of the large-bag long sprue 5 obtained from the image processing unit 2 are used to determine the opening value G of the large-bag long sprue 5 by the calculation output unit, where G = (P - P0) / P S *100%.

[0116] Combination Figure 3 As shown, step S3, which involves monitoring the tightening signal of the long nozzle 5 of the large package to trigger the automatic calibration unit 3 to start zero-position data acquisition and record it to the zero-position data queue, specifically includes the following steps:

[0117] S31, a pressure sensor is installed in the air circuit of the lifting device of the large package long water inlet 5, and the sensor signal is sent to the automatic calibration unit 3;

[0118] In this embodiment, the pressure sensor is a pressure switch with dry contact output;

[0119] S32, when the long water inlet 5 of the large package rises and presses against the sliding water inlet 6 of the large package, the pressure signal in the lifting air path exceeds the set threshold and sends a pressing detection signal for the long water inlet 5 of the large package.

[0120] In this embodiment, the pressure switch is set to a threshold of 150 kgf. When the cylinder clamping force exceeds 150 kgf, the pressure switch contacts are closed, and a clamping detection signal is sent to the large package long water inlet 5.

[0121] S33, after receiving the tightening detection signal of the long water inlet 5 of the large package, the automatic calibration unit 3 sets the zero-position data acquisition flag and starts to continuously acquire the position coordinate data of the long water inlet 5 of the large package from the image processing unit 2 and record and save it to the zero-position data queue.

[0122] The zero-position data queue in step S33 above is a collection of candidate zero-position coordinate data of the long water inlet of the large package, which are collected and arranged in a first-in-first-out manner according to a certain frame scanning interval period.

[0123] In this embodiment, the zero-position data queue length is 10 data points, and the continuous frame scanning interval is 1 second. After zero-position acquisition is started, the data recorded in the zero-position data queue is as follows: [631, 630, 630, 655, 662, 650, 650, 651, 651, 650]. At this time, the first data in the queue is the position coordinate of the large package water inlet recorded when the long water inlet is tightened, which is 631. The fourth data in the queue changes to 655, indicating that the long water inlet is tilted when tightened. After tightening, the operator performed a long water inlet position correction operation, which caused the detected water inlet position coordinates to change.

[0124] Combination Figure 4 As shown, in step S4, the opening signal of the sliding nozzle 6 of the large ladle 8 triggers the automatic calibration unit 3 to stop zero-position data acquisition and select the zero-position frame from the zero-position data queue to automatically complete the update and calibration of the zero-position coordinate P0 of the long nozzle 5 of the large ladle. Specifically, this includes the following steps:

[0125] S41, when the automatic calibration unit 3 receives the signal that the sliding gate 6 of the large ladle 8 opens when it starts pouring, it automatically resets the zero-position data acquisition flag and stops the acquisition and update of the zero-position data queue.

[0126] In this embodiment, the opening signal of the sliding gate 6 of the large ladle 8 when it is poured is acquired by the automatic calibration unit 3 from the sliding gate control system 7 of the large ladle through the industrial Ethernet TCP / IP communication method.

[0127] In this embodiment, after the zero-position data acquisition is stopped, the data recorded in the zero-position data queue is as follows: [651, 650, 650, 650, 649, 650, 651, 650, 770, 893]; it can be seen that although the zero-position data acquisition has been stopped when the water inlet opening signal is received, due to the influence of communication delay, the last two frames of data in the queue are already the coordinate data after the water inlet leaves the zero position;

[0128] S42, calculate the rate of change of the water inlet position in adjacent frames sequentially from back to front along the zero-position data queue, V i =(D i -D i-1 ) / T;

[0129] Let the zero-point data queue be [D1, D2, ..., D] when zero-point data acquisition stops. i D n-1 D n ], D n The last frame of the water inlet position coordinates recorded when zero-position data acquisition stops is the water inlet position coordinates of the previous frame, Dn-1 is the water inlet position coordinates of the i-th frame, Di is the water inlet position coordinates of the i-th frame, and T is the frame scanning interval.

[0130] In this embodiment, n=10, frame scanning interval T=1s, when zero-position data acquisition stops, the coordinate data D9 and D10 of the last two image frames in the zero-position data queue are 770 and 893 respectively, and the water inlet position change rate V10 of adjacent frames is 123p / s.

[0131] S43, after each calculation, determine the rate of change V of the water inlet position. i If the position change rate is lower than the minimum water inlet switching rate, then determine the next frame of the adjacent frame as the zero position frame; otherwise, return to step S42 to continue calculating the position change rate of the previous pair of adjacent frames.

[0132] In this embodiment, the minimum sprue switching rate is set based on the change in position coordinate data per unit time during the test of the large package sliding sprue 6 switching action. In this embodiment, the minimum sprue switching rate is set to 100p / s.

[0133] In this embodiment, V10 = 123p / s and V9 = 120p / s were calculated successively, both of which are greater than the minimum gate opening rate of 100p / s; further, the gate position change rate V8 of adjacent frames D7 and D8 was calculated to be -1p / s, which is lower than the minimum gate opening rate. Therefore, the next frame D8 after adjacent frames D7 and D8 is determined to be the zero frame, and the position coordinate of the zero frame is 650p.

[0134] S44: Perform a confidence check on the position coordinates of the zero-position frame. If it is within the zero-position confidence interval, it is adopted, updated, and transmitted to the zero-position coordinate P0 of the large packet long water inlet 5. If it is outside the zero-position confidence interval, it is not adopted or updated.

[0135] In step S44 above, the zero position information interval of the long nozzle 5 of the large ladle is determined by statistically analyzing the distribution interval of the change in the image position coordinates of the long nozzle 5 of the large ladle when the normal large ladle 8 is rotated to the pouring position.

[0136] In this embodiment, the zero position information interval of the large package long water inlet 5 is set to 600~700p, and the position coordinate of the zero frame is 650p. Then, this value is adopted and transmitted to the zero position coordinate P0 of the large package long water inlet 5, P0 = 650p.

[0137] In step S5 above, the opening range P of the large package long nozzle 5 is... S It is achieved by recording and calculating the corresponding gate position coordinates P when the sliding gate 6 of the large package is fully open. opn The coordinates P of the water inlet when it is fully closed. cls The difference is used to determine P. S =P opn -P cls ;

[0138] Since the stroke range of the hydraulic cylinder driving the sliding gate 6 is fixed, the fully open position coordinate P opn and the coordinates of the full position P cls The difference also shows a relatively fixed value, which can be determined by obtaining the fully open and fully closed position coordinates of the sliding gate 6 of the large package from the image processing unit 2 through the full stroke action test of the large package 8 at the pouring position.

[0139] In this example, the hydraulic cylinder stroke of the sliding gate 6 in the ladle is 150mm. The position coordinate P of the gate when the sliding gate 6 is fully open was determined by testing the full stroke of the gate at the pouring position using the ladle 8. opn =1231p, the coordinates of the water inlet P when fully closed. cls =631p, the opening range P of the large package with long water inlet 5. S =P opn -P cls =600p.

[0140] In this embodiment, the automatic calibration unit 3 can automatically perform zero-position update calibration before pouring after the ladle 8 of each heat of steel is rotated to the pouring position, effectively eliminating the influence of the zero-position error of the ladle long nozzle 5 and improving the accuracy and reliability of the ladle nozzle visual opening detection system.

[0141] Those skilled in the art should recognize that the above embodiments are merely illustrative of the present invention and are not intended to limit the present invention. Any variations or modifications to the above embodiments that are within the spirit and essence of the present invention will fall within the scope of the claims of the present invention.

Claims

1. A self-calibrating visual opening detection system for large-scale sprue nozzles, characterized in that, include: Image acquisition unit, used to acquire images of the location of the long sprue inlet of the large package; The image processing unit is used to acquire image information emitted by the image acquisition unit in real time, automatically perform target recognition on the image of the large package long sprue, and detect and record the current position coordinates of the large package long sprue in real time. The automatic calibration unit acquires and records the pressure signal of the large package long nozzle, filters and determines the zero position coordinate of the large package long nozzle, and also determines the opening range of the large package long nozzle. The calculation output unit calculates and obtains the opening value of the long water inlet of the large package based on the position coordinates, zero position coordinates and opening range of the long water inlet.

2. The self-calibrated visual opening detection system for large-capacity sprue nozzles according to claim 1, characterized in that, The image acquisition unit includes: The industrial camera, which is a network camera with a high-definition lens, is used to capture images of the pouring area on the long nozzle of the large ladle in real time and send the image signal to the image processing unit. A protective cover, employing a water-air composite cooling protective cover, is installed on the outside of the industrial camera to protect it. The pan-tilt bracket uses a three-dimensional adjustable pan-tilt head, which is connected to the industrial camera to adjust the angle and position of the industrial camera.

3. The self-calibrated visual opening detection system for large-capacity sprue nozzles according to claim 1, characterized in that, The automatic calibration unit includes: The signal monitoring module is used to start and stop the zero-position data acquisition of the large package long water inlet; The data recording module continuously acquires the position coordinates of the large package long nozzle from the image processing unit according to the zero-position acquisition start signal sent by the signal monitoring module, and records them in the zero-position data queue; at the same time, it stops updating the zero-position data queue according to the zero-position acquisition stop signal sent by the signal monitoring module. The zero-position filtering module is used to filter out reliable zero-position frames of the large package long nozzle image from the zero-position data queue recorded by the data recording module, and determine the zero-position coordinates of the large package long nozzle. The range prediction module is used to determine the opening range of the long nozzle of the large package in advance based on the difference between the fully open position coordinates and the fully closed position coordinates of the sliding nozzle of the large package.

4. The self-calibrated visual opening detection system for large-capacity sprue nozzles according to claim 3, characterized in that, The signal monitoring module includes: The zero-position acquisition start signal monitoring module uses a pressure sensor and is installed on the lifting air path of the long water inlet of the large package. When the pressure detection value exceeds the set threshold, the long water inlet of the large package is in the tightened state, and a zero-position acquisition start signal is sent to the data recording module. The zero-position acquisition stop signal monitoring module establishes data communication with the large package sliding gate control system, receives the gate opening signal from the large package sliding gate control system to indicate the opening state of the large package sliding gate, and sends a zero-position acquisition stop signal to the data recording module.

5. A self-calibrated visual opening detection method for large-capacity sprue nozzles, characterized in that, Using the self-calibrated large-package sprue visual opening detection system as described in any one of claims 1-4, the following steps are performed: S1, The image acquisition unit acquires images of the pouring area on the long nozzle of the large package in real time; S2, after the large ladle is rotated to the pouring position, the image processing unit identifies and detects the image of the pouring area on the long nozzle of the large ladle, and records the position coordinates P of the long nozzle of the large ladle corresponding to each frame of the image in real time; S3, by monitoring the tightening signal of the large package long nozzle, the automatic calibration unit is triggered to start zero-position data acquisition and record it to the zero-position data queue; S4, by triggering the opening signal of the sliding nozzle of the large bag when the large bag starts pouring, the automatic calibration unit is triggered to stop zero-position data acquisition, and the zero-position frame is selected from the data queue to automatically complete the update calibration of the zero-position coordinate P0 of the long nozzle of the large bag. S5, based on the zero-position coordinate P0 of the large package long water nozzle and the opening range P of the large package long water nozzle. S The location coordinates P of the large package long sprue nozzle are used to determine the opening value G of the large package long sprue nozzle through the calculation output unit, i.e., G = (P - P0) / P. S *100%.

6. The self-calibrated visual opening detection method for the large-capacity sprue nozzle according to claim 5, characterized in that, Step S3 specifically includes the following steps: S31, the zero-position acquisition start signal monitoring module is installed on the lifting air path of the large package long water inlet, and the monitoring signal of the zero-position acquisition start signal monitoring module is sent to the automatic calibration unit. S32, when the long water inlet of the large package rises and presses against the sliding water inlet of the large package, the pressure signal in the lifting air path of the long water inlet of the large package exceeds the set threshold, and a pressing detection signal of the long water inlet of the large package is issued. S33, upon receiving the top-tightening detection signal, the automatic calibration unit sets the zero-position data acquisition flag and begins to continuously acquire the position coordinate data of the long water inlet of the large package from the image processing unit, and records and saves it to the zero-position data queue.

7. The self-calibrated visual opening detection method for the large-capacity sprue nozzle according to claim 6, characterized in that, In step S33, the zero-position data queue is a collection of candidate zero-position coordinate data of the large-capacity water inlet, which are collected and arranged in a first-in-first-out manner according to a set frame scanning interval period.

8. The self-calibrated visual opening detection method for large-capacity sprue nozzles according to claim 5, characterized in that, Step S4 specifically includes the following steps: S41, when the automatic calibration unit receives the signal that the sliding gate of the ladle is opened when the ladle is started to pour, it automatically resets the zero-position data acquisition flag and stops the acquisition and update of the zero-position data queue. S42, calculate the rate of change of the water inlet position in adjacent frames sequentially from back to front along the zero-position data queue, V i =(D i -D i-1 ) / T; Let the zero-point data queue be [D1, D2, ..., D when zero-point data acquisition stops.] i D n-1 D n ], D n D is the coordinate of the last water inlet position recorded when zero-position data acquisition stops. n-1 D represents the coordinates of the sprue position in the previous frame. i Let be the coordinates of the water inlet position in the i-th frame, and T be the frame scanning interval; S43, after each calculation, determine the rate of change V of the water inlet position. i If the position change rate is lower than the minimum water inlet switching rate, then determine the next frame of the adjacent frame as the zero position frame; otherwise, return to step S42 to continue calculating the position change rate of the previous pair of adjacent frames. S44, perform a confidence judgment on the position coordinates of the zero-position frame. If it is within the zero-position confidence interval, it is adopted, updated, and transmitted to the zero-position coordinate P0 of the large package long water inlet. If it is outside the zero-position confidence interval, it is not adopted and updated.

9. The self-calibrated visual opening detection method for the large-capacity sprue nozzle according to claim 8, characterized in that, In step S44, the zero position information interval of the large package is determined by statistically analyzing the distribution interval of the change in the position coordinates of the long nozzle image when the large package is rotated to the pouring position.

10. The self-calibrated visual opening detection method for large-capacity sprue nozzles according to claim 5, characterized in that, In step S5, the opening range P of the large package long nozzle is... S It is achieved by recording and calculating the corresponding gate position coordinate P when the sliding gate of the large package is fully open. opn The coordinates P of the water inlet when it is fully closed. cls The difference is used to determine P. S =P opn -P cls .

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