Method for identifying section steel flying shear head cutting length

Abstract

The invention relates to a section steel flying shear head cutting length identification method, and belongs to the technical field of head cutting length identification in the metallurgical industry. According to the technical scheme, an image of an industrial camera is read, and a pre-shearing thermal detection signal of a flying shear mechanism is read; if the pre-shearing thermal detection signal of the flying shear mechanism is True, analyzing the read image of the industrial camera; the section steel flying shear head is accurately captured according to the real-time analysis result; analyzing the obtained profile steel flying shear head image to obtain the pixel length of the profile steel flying shear head image; and the actual length is calculated according to the pixel length of the profile steel flying shear head. The method has the beneficial effects that by measuring the length of the flying shear head, the cutting precision and the production efficiency are improved, the service life of equipment is prolonged, materials and cost are saved, the method has a remarkable effect on optimization of the whole production process, implementation is easy, and the method has the advantages of being low in cost, high in efficiency, easy to implement, high in accuracy and the like.

Description

Technical Field

[0001] The invention relates to a method for identifying the length of a section steel flying shearing head, and belongs to the technical field of identifying the length of a shearing head in the metallurgical industry. Background Art

[0002] In the steel and metal processing industry, flying shear technology is used for high-speed online cutting of steel sections, plates and other metals. Steel sections are widely used in construction, bridges and other fields, and their processing accuracy and quality requirements are high. In particular, during the cutting process, it is necessary to ensure dimensional consistency. At the same time, in order to obtain a low cutting loss rate, it is necessary to reduce the cutting of the rest of the steel section except for the head that should be cut. The existing flying shear length measurement methods mostly rely on manual labor, and there are problems such as low measurement efficiency and untimely response. Summary of the invention

[0003] The purpose of the present invention is to provide a method for identifying the length of a flying shear head for steel sections. By measuring the length of the flying shear head, the cutting accuracy and production efficiency are improved, the equipment life is extended, materials and costs are saved, and the overall production process is optimized, thereby solving the above-mentioned technical problems existing in the prior art.

[0004] The technical solution of the present invention is: A method for identifying the length of a steel section flying shear head comprises the following steps: ① Read the industrial camera image and the pre-cutting heat detection signal of the flying shear mechanism; ② If the pre-cutting heat detection signal of the flying shear mechanism is True, analyze the read industrial camera image; ③ Accurately capture the flying shear head of the steel section through real-time analysis results; ④ Analyze the obtained image of the flying shear head of the steel section to obtain its pixel length; ⑤ Calculate its actual length based on the pixel length of the flying shear head of the steel section.

[0005] The industrial camera described in step ① is a high-temperature resistant, high-frame-rate industrial camera, which is installed obliquely above the flying shear mechanism. The industrial camera passes through a switch and is read by a computer's Python program; the pre-cutting thermal detection signal of the flying shear mechanism is read from the PLC by the computer's Python program.

[0006] The image analysis described in step ② is specifically performed as follows: selecting a flying shear mechanism area as an image analysis area, and performing probabilistic Hough line detection in the image analysis area.

[0007] The specific method for capturing the flying shear head of the steel section described in step ③ is: when the image analysis in step ② detects a straight line that meets the requirements, that is, a frame in which the flying shear just contacts the surface of the steel section, the flying shear head of the steel section is captured, and each steel section is captured only once.

[0008] The pixel length described in step ④ is specifically calculated by filtering and binarizing the image of the steel flying shear head captured in step ③, performing contour detection on the preprocessed image to find the largest contour, that is, the contour of the steel flying shear head, and at the same time performing probabilistic Hough line detection on the preprocessed image to screen out a straight line that meets the conditions, that is, the straight line formed by the flying shear just contacting the steel surface, and calculating the distance from the midpoint of the straight line to the point with the largest y coordinate of the contour as the pixel length of the steel flying shear head.

[0009] The actual length described in step ⑤ is calculated from the pixel length, specifically: use a ruler to measure the actual length of the steel flying shear head, compare it with the pixel length, calculate the actual length d corresponding to one pixel length, and then calculate the actual length based on d.

[0010] The image analysis process is implemented by OpenCV in Python.

[0011] The specific method for calculating the pixel length of the flying shear head of the steel section is as follows: find the coordinates of the midpoint of the straight line, that is, the midpoint A (x A ,y A ), find the point with the largest y coordinate of the profile of the flying shear head, that is, the midpoint B (x B ,y B ), calculate the distance D between the two points 像 As the pixel length of the steel flying shear head; D 像 =

[0012] Use a ruler to measure the actual length of the steel flying shear head and compare it with its pixel length. Calculate the actual length d corresponding to one pixel length, and then calculate the actual length D of other steel flying shear heads based on d. 实 ; D 实 =d*D 像 All the above image analysis processes are implemented by Python's OpenCV, and the data calculation process is also implemented by Python programs.

[0013] The beneficial effects of the present invention are as follows: by measuring the length of the flying shear head, the cutting accuracy and production efficiency are improved, the equipment life is extended, materials and costs are saved, and it has a significant effect on the optimization of the overall production process. The implementation is simple and has the advantages of low cost, high efficiency, easy implementation, and high accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a flow chart of an embodiment of the method of the present invention; Figure 2A system diagram of an embodiment of the method of the present invention; In the figure: 1. Industrial camera, 2. Flying shear mechanism, 3. Steel flying shear head, 4. Switch, 5. Computer, 6. PLC. DETAILED DESCRIPTION

[0015] The present invention will be further described below by way of embodiments in conjunction with the accompanying drawings.

[0016] A method for identifying the length of a steel section flying shear head comprises the following steps: ① Read the industrial camera image and the pre-cutting heat detection signal of the flying shear mechanism; ② If the pre-cutting heat detection signal of the flying shear mechanism is True, analyze the read industrial camera image; ③ Accurately capture the flying shear head of the steel section through real-time analysis results; ④ Analyze the obtained image of the flying shear head of the steel section to obtain its pixel length; ⑤ Calculate its actual length based on the pixel length of the flying shear head of the steel section.

[0017] The industrial camera described in step ① is a high-temperature resistant, high-frame-rate industrial camera, which is installed obliquely above the flying shear mechanism. The industrial camera passes through a switch and is read by a computer's Python program; the pre-cutting thermal detection signal of the flying shear mechanism is read from the PLC by the computer's Python program.

[0018] The image analysis described in step ② is specifically performed as follows: selecting a flying shear mechanism area as an image analysis area, and performing probabilistic Hough line detection in the image analysis area.

[0019] The specific method for capturing the flying shear head of the steel section described in step ③ is: when the image analysis in step ② detects a straight line that meets the requirements, that is, a frame in which the flying shear just contacts the surface of the steel section, the flying shear head of the steel section is captured, and each steel section is captured only once.

[0020] The pixel length described in step ④ is specifically calculated by filtering and binarizing the image of the steel flying shear head captured in step ③, performing contour detection on the preprocessed image to find the largest contour, that is, the contour of the steel flying shear head, and at the same time performing probabilistic Hough line detection on the preprocessed image to screen out a straight line that meets the conditions, that is, the straight line formed by the flying shear just contacting the steel surface, and calculating the distance from the midpoint of the straight line to the point with the largest y coordinate of the contour as the pixel length of the steel flying shear head.

[0021] The actual length described in step ⑤ is calculated from the pixel length, specifically: use a ruler to measure the actual length of the steel flying shear head, compare it with the pixel length, calculate the actual length d corresponding to one pixel length, and then calculate the actual length based on d.

[0022] The image analysis process is implemented by OpenCV in Python.

[0023] The flow chart of the method for identifying the length of the steel flying shear head provided by the present invention is as follows: Figure 1 As shown, the following steps are included: At the beginning, read the image of industrial camera 1, read the pre-cutting heat detection signal of flying shear mechanism 2, judge whether the pre-cutting heat detection signal is True, if not, continue to detect; if yes, perform probabilistic Hough line detection on the specified straight line of the image, judge whether the straight line that meets the requirements is detected, if not, continue to detect; if yes, capture the image of steel flying shear head 3, perform contour recognition and probabilistic Hough line detection on the captured image; calculate the pixel length of steel flying shear head 3 and convert it into actual length output. Industrial camera 1 is connected to computer 5 through switch 4 to process the image collected by industrial camera 1; PLC6 that controls flying shear mechanism 2 is connected to computer 5 to control the action of flying shear mechanism 2.

[0024] The embodiment of the method for identifying the length of the steel flying shear head provided by the present invention is shown in FIG. Figure 2 As shown: The industrial camera 1 is installed obliquely above the flying shear mechanism 2. The industrial camera 1 is read by the Python program of the computer 5 through the switch 4; the pre-shear heat detection signal is read from the PLC by the Python program of the computer. When the pre-shear heat detection signal is True, that is, the steel is close to the flying shear mechanism 2, the probabilistic Hough line detection of the flying shear area begins. When the detected straight line is in the specified area (flying shear area), the detected straight line meets the specified length range (between 305-310 pixels in length), and the detected straight line meets the specified inclination angle range (horizontal ±3 o ), that is, a frame in which the flying shear just contacts the surface of the steel section, the flying shear head 3 of the steel section is captured, and only one capture is performed for each steel section.

[0025] The captured steel flying shear head image is filtered and binarized to reduce the influence of noise. The preprocessed image is subjected to contour detection to find the largest contour, that is, the contour of the steel flying shear head. At the same time, the preprocessed image is subjected to probabilistic Hough line detection to screen out a straight line that meets the conditions, that is, the straight line formed by the flying shear just contacting the steel surface; according to the identified straight line and the contour of the steel flying shear head, the 3-pixel length of the steel flying shear head is calculated. The specific method is: find the coordinates of the midpoint of the straight line, that is, the midpoint A (x A ,y A ), find the point with the largest y coordinate of the profile of the flying shear head, that is, the midpoint B (x B ,y B ), calculate the distance D between the two points 像As the pixel length of the steel flying shear head.

[0026] D 像 =

[0027] Use a ruler to measure the actual length of the steel flying shear head and compare it with its pixel length. Calculate the actual length d corresponding to one pixel length, and then calculate the actual length D of other steel flying shear heads based on d. 实 .

[0028] D 实 =d*D 像 All the above image analysis processes are implemented by Python's OpenCV, and the data calculation process is also implemented by Python programs.

[0029] It should be noted that after the camera is installed, the focus, shutter, white balance and other parameters of the camera need to be adjusted to achieve the most accurate effect when processing the image.

Claims

1. A method for identifying the length of a steel flying shear head, characterized in that The following steps are involved: ① Read the industrial camera image and the pre-cutting heat detection signal of the flying shear mechanism; ② If the pre-cutting heat detection signal of the flying shear mechanism is True, analyze the read industrial camera image; ③ Accurately capture the flying shear head of the steel section through the real-time analysis results; ④ Analyze the obtained flying shear head image of the steel section to obtain its pixel length; ⑤ Calculate the actual length based on the pixel length of the steel flying shear head.

2. The method for identifying the length of a steel section flying shear head according to claim 1, characterized in that: The industrial camera described in step ① is a high-temperature resistant, high-frame-rate industrial camera, which is installed obliquely above the flying shear mechanism. The industrial camera passes through a switch and is read by a computer's Python program; the pre-cutting thermal detection signal of the flying shear mechanism is read from the PLC by the computer's Python program.

3. The method for identifying the length of a steel section flying shear head according to claim 2, characterized in that: The image analysis described in step ② is specifically performed as follows: selecting a flying shear mechanism area as an image analysis area, and performing probabilistic Hough line detection in the image analysis area.

4. The method for identifying the length of a steel section flying shear head according to claim 3 is characterized in that: The specific method for capturing the flying shear head of the steel section described in step ③ is: when the image analysis in step ② detects a straight line that meets the requirements, that is, a frame in which the flying shear just contacts the surface of the steel section, the flying shear head of the steel section is captured, and each steel section is captured only once.

5. The method for identifying the length of a steel section flying shear head according to claim 4 is characterized in that: The pixel length described in step ④ is specifically calculated by filtering and binarizing the image of the steel flying shear head captured in step ③, performing contour detection on the preprocessed image to find the largest contour, that is, the contour of the steel flying shear head, and at the same time performing probabilistic Hough line detection on the preprocessed image to screen out a straight line that meets the conditions, that is, the straight line formed by the flying shear just contacting the steel surface, and calculating the distance from the midpoint of the straight line to the point with the largest y coordinate of the contour as the pixel length of the steel flying shear head.

6. The method for identifying the length of a steel section flying shear head according to claim 5, characterized in that: The actual length described in step ⑤ is calculated from the pixel length, specifically: use a ruler to measure the actual length of the steel flying shear head, compare it with the pixel length, calculate the actual length d corresponding to one pixel length, and then calculate the actual length based on d.

7. The method for identifying the length of a steel section flying shear head according to claim 5, characterized in that: The specific method for calculating the pixel length of the flying shear head of the steel section is as follows: find the coordinates of the midpoint of the straight line, that is, the midpoint A (x A ,y A ), find the point with the largest y coordinate of the profile of the flying shear head, that is, the midpoint B (x B ,y B ), calculate the distance D between the two points 像 As the pixel length of the steel flying shear head; D 像 = 8. Use a ruler to measure the actual length of the steel flying shear head, compare it with its pixel length, and calculate the actual length d corresponding to one pixel length. Then use d to calculate the actual length D of other steel flying shear heads. 实 ; D 实 =d*D 像 All the above image analysis processes are implemented by Python's OpenCV, and the data calculation process is also implemented by Python programs.

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