Vacuum pouring liquid level visual detection device and method based on laser light source

Abstract

The invention belongs to the field of pouring liquid level detection, and particularly relates to a vacuum pouring liquid level visual detection device and method based on a laser light source, and the device comprises an image collection unit which is arranged right above a pouring unit, is connected with an image processing host through a host connection cable, and is used for receiving a shooting instruction; the collected liquid level image of the pouring unit irradiated by the laser is sent to the image processing host for processing; the laser unit is connected with the image processing host and is used for emitting laser to the pouring unit; the pouring unit is connected with the pouring material port controller and used for receiving a pouring instruction of the image processing host and completing the pouring process according to an automatic judgment rule. And the image processing host is used for carrying out image processing operation on the liquid level image of the pouring unit irradiated by the laser and measuring the liquid level height through an image laser line position detection algorithm according to the obtained processed image. According to the invention, the accuracy degree of liquid level height calculation is greatly improved, so that the control accuracy of the automatic visual gating system is improved.

Description

Technical Field

[0001] The invention belongs to the field of pouring liquid level detection, in particular to a vacuum pouring liquid level visual detection device and method based on a laser light source. Background Art

[0002] Vacuum casting technology refers to the technology of using epoxy resin casting in a vacuum environment. Compared with normal pressure casting technology, vacuum casting can more easily discharge bubbles in the casting material and greatly improve the quality of the product. During the casting process, the pouring cup, casting and riser cup are made in a sand mold and connected to each other. The upper part is the pouring cup, the lower part is the casting, and the casting is connected to the bottom of the riser cup. The pouring liquid is injected into the lower part of the casting through the pouring cup, and flows into the riser cup from the bottom, while the liquid level of the riser cup rises. By continuously injecting material liquid into the pouring cup and keeping the pouring and riser liquid levels equal, the pouring is completed when the riser cup and the pouring cup are full. When the liquid flow rate injected into the pouring cup is too large, due to the certain viscosity of the pouring liquid, the riser liquid level rise speed cannot keep up with the pouring liquid inflow speed, and the liquid will flow out of the pouring cup, resulting in waste. When the liquid flow rate is too small, the liquid level cannot be quickly established in the pouring cup, and defective products will be produced. Therefore, it is necessary to monitor and measure the height of the liquid level in the pouring cup and the riser cup in real time. However, it is difficult to use general sensors to measure the liquid level under vacuum and high temperature conditions. How to monitor and measure the height of the liquid level in the pouring cup and the riser cup in real time under vacuum and high temperature conditions has become a difficulty.

[0003] With the development of science and technology, the research direction mainly focuses on using cameras to collect liquid surface images, using control algorithms and image processing methods to extract image feature information of the pouring liquid surface, and then using the existing information to better control the pouring process to achieve a more ideal pouring effect. At present, the image processing of the automatic visual pouring system adopts a simple area method, which uses the calculation of the liquid surface area of ​​the collected image to indirectly judge whether the liquid surface has reached a fixed height. There are several deficiencies:

[0004] 1) Affected by external light, the grayscale or color of the collected liquid surface image will be different under different light, causing the system to distort the statistics of the liquid surface image area, greatly affecting the stability of the automatic visual pouring system;

[0005] 2) The threshold for judging the liquid surface area changes with the change in the diameter of the pouring cup and the riser cup. In the actual pouring process, the diameters of the pouring cup and the riser cup will change accordingly depending on the casting. The application of the image liquid surface area method reduces the control accuracy of the automatic visual pouring system. Summary of the invention

[0006] The object of the present invention is to provide a vacuum pouring liquid level visual detection device and method based on a laser light source to overcome the defects of the above-mentioned automatic visual pouring system.

[0007] The technical solution adopted by the present invention to achieve the above-mentioned purpose is: a vacuum pouring liquid level visual detection device based on a laser light source, comprising: an image processing host, a pouring nozzle controller, a pouring unit, a laser unit and an image acquisition unit;

[0008] The image acquisition unit is arranged directly above the pouring unit and is connected to the image processing host through a host connection cable, and is used to receive shooting instructions and send the collected laser-irradiated pouring unit liquid surface image to the image processing host for processing;

[0009] The laser unit is connected to the image processing host and is used to receive a start instruction from the image processing host and emit laser to the pouring unit;

[0010] The pouring port controller is connected to the image processing host through a controller cable, and the pouring unit is connected to the pouring port controller, and is used to receive the pouring instruction from the image processing host and complete the pouring process according to the automatic judgment rule;

[0011] The image processing host is used to receive the laser-irradiated pouring unit liquid surface image, perform image processing operations, and measure the liquid surface height through an image laser line position detection algorithm based on the processed image.

[0012] The pouring unit comprises: a vacuum pouring box and a pouring port, a pouring cup, a riser cup and a casting mold arranged inside the vacuum pouring box;

[0013] The casting mold is arranged at the center of the vacuum pouring box, and a pouring cup and a riser cup are symmetrically arranged at both ends of the top surface of the casting mold; the pouring material port is corresponding to the top of the pouring cup; the image acquisition unit is corresponding to the top of the riser cup;

[0014] A laser unit is provided on the top of one side of the vacuum pouring box corresponding to the pouring cup;

[0015] The pouring port is connected to a pouring port controller via a cable and is used to receive control of the pouring port controller to perform pouring operations.

[0016] The image acquisition unit comprises: a glass sheet and a camera;

[0017] The glass sheet is embedded on the top surface of the vacuum pouring box and is directly above the cup openings of the pouring cup and the riser cup; a camera is provided above the glass sheet;

[0018] The camera is a high-resolution color camera, the field of view of the camera is perpendicular to the glass sheet, and the field of view of the camera covers the liquid surface of the pouring cup and the riser cup;

[0019] The camera is connected to the image processing host via a host connection cable to receive shooting instructions and send the collected images to the image processing host.

[0020] The glass sheet is a bandpass filtering tempered glass sheet;

[0021] The thickness of the glass sheet is 15 mm to 20 mm; the surface of the glass sheet is coated with a narrow-band filter coating, which allows the wavelength of light to pass through to be between 500 nm and 600 nm;

[0022] The laser unit comprises: a linear laser light source and a light source controller connected thereto;

[0023] The line laser light source is arranged at the top of the vacuum pouring box, and the laser emitted by it covers the liquid surface of the pouring cup and the riser cup;

[0024] The light source controller is connected to the image processing host and is used to receive instructions from the image processing host and turn on the line laser light source.

[0025] A detection method of a vacuum casting liquid level visual detection device based on a laser light source comprises the following steps:

[0026] 1) The image processing host turns on the line laser light source through the light source controller. The line laser light source projects the laser line on the liquid surface of the pouring cup and the riser cup, and sends a pouring instruction to the pouring controller to start pouring raw materials into the pouring cup. The feeding speed of the pouring port is divided into a fast gear and a slow gear. When pouring starts, the pouring port controller controls the pouring port to use the fast gear for pouring;

[0027] 2) The image processing host sends a shooting instruction to the camera, receives the image from the camera, and performs image processing operations on the image to obtain a processed image;

[0028] 3) Setting the warning line and safety line of the liquid level; the image processing host measures the liquid level according to the processed image through the image laser line position detection algorithm;

[0029] 4) The image processing host calculates the liquid level of the pouring cup and the riser cup according to the image, and completes the pouring process according to the automatic judgment rules;

[0030] 5) When the liquid level at the riser reaches the warning line, pouring is completed.

[0031] The step 2) is specifically:

[0032] 2-1) Preprocessing the laser line speckle image: performing laser imaging parameter calculation, Gaussian gain coefficient calculation, and adaptive contrast image enhancement operations on the laser line speckle image;

[0033] 2-2) obtaining the position of the laser line breakpoint in the preprocessed image, and performing grayscale expansion operation on the image;

[0034] 2-3) The center coordinates of the laser line in the image are extracted through Gaussian filtering and Hessian matrix transformation.

[0035] The liquid level is measured by the image laser line position detection algorithm, specifically:

[0036] 3-1) Set point A as a point on the laser line when the liquid level is full, point B as a point on the laser line at the current liquid level, and point C as the emission point of the laser light source;

[0037] 3-2) Points A, B, and C form a triangular section, and the height difference h between the current liquid surface and the cup mouth plane is:

[0038] h=tanθ×L

[0039] Wherein, θ is the angle between the laser light source and the liquid surface, and L is the horizontal distance between the laser line when the liquid surface is full and the laser line at the current liquid surface height;

[0040] 3-3) Set A1 as the vertical projection of A, and get the horizontal distance L between the laser line when the liquid level is full and the laser line at the current liquid level, that is:

[0041] L=PL×ε

[0042] Where PL is the number of image pixels between the laser line at full liquid level and the laser line at the current liquid level, ε is the minimum measurement length of the imaging system, and its unit is mm / pixel;

[0043] 3-4) According to step 3-2) to step 3-3), the height difference h between the current liquid surface and the cup mouth plane is:

[0044] h=tanθ×PL×ε

[0045] 3-5) According to the triangle principle, obtain the liquid level U of the pouring cup or riser cup h ,Right now:

[0046] U h =U l -h

[0047] Among them, U l is the vertical height of the pouring cup or riser cup, U h It is the liquid level height of pouring cup or riser cup.

[0048] The pouring process is completed according to the automatic judgment rule, specifically:

[0049] 4-1) When the liquid levels of the pouring cup and the riser cup are both below the safety line, a fast gear injection instruction is sent to the pouring controller;

[0050] 4-2) When the liquid level of the pouring cup or the riser cup is between the safety line and the warning line, a slow gear injection instruction is sent to the pouring controller;

[0051] 4-3) When the liquid level in the pouring cup or riser cup is higher than the warning line, the pouring instruction is sent to the pouring controller to stop.

[0052] The present invention has the following beneficial effects and advantages:

[0053] 1. The automatic control pouring device and method of the vacuum pouring liquid level visual detection device based on a laser light source of the present invention can solve the pouring liquid level control problem in manual pouring, greatly improve the pouring efficiency, and at the same time reduce the resource waste problem of material overflow caused by inaccurate manual monitoring of the liquid level position and reduce the probability of defective products.

[0054] 2. A method for calculating the liquid level based on line laser was invented, which solved the problem of inaccurate calculation caused by the area method used by the existing visual pouring system to indirectly judge the liquid level due to changes in external light, and greatly improved the stability of the automatic visual pouring system.

[0055] 3. This paper invents a method for extracting the center of a laser speckle light strip, which can greatly improve the accuracy of liquid level calculation in actual application scenarios, thereby improving the control accuracy of the automatic visual pouring system. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 This is a block diagram of the vacuum casting liquid level visual detection device of the present invention;

[0057] Among them, 1 is a vacuum pouring box, 2 is a pouring port, 3 is a pouring cup, 4 is a riser cup, 5 is a casting mold, 6 is a glass sheet, 7 is a camera, 8 is a line laser light source, 9 is a light source controller, 10 is an image processing host, 11 is a host connection cable, 12 is a connection cable, and 13 is a controller cable;

[0058] Figure 2 It is a schematic diagram and actual image of the pouring cup and riser cup of the present invention;

[0059] Figure 3a It is a state diagram for calculating the liquid level of the pouring cup and the riser cup of the present invention;

[0060] Figure 3bIt is a schematic diagram of the calculation principle of the liquid level of the pouring cup and the riser cup of the present invention;

[0061] Figure 4 This is the laser line center extraction flow chart of the present invention. DETAILED DESCRIPTION

[0062] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0063] Attached Figure 1-4 This is an example of a visual inspection platform based on AR technology. Figure 1 As shown, the elements of the applicable scene of the vacuum pouring liquid level visual detection method based on the laser light source, the present invention is a vacuum pouring liquid level visual detection device based on the laser light source, including: an image processing host 10, a pouring nozzle controller, a pouring unit, a laser unit and an image acquisition unit;

[0064] 1. Image acquisition unit

[0065] The image acquisition unit is arranged directly above the pouring unit and is connected to the image processing host 10 via the host connection cable 11, and is used to receive shooting instructions and send the collected laser-irradiated pouring unit liquid surface image to the image processing host 10 for processing;

[0066] An image acquisition unit, comprising: a glass sheet 6 and a camera 7;

[0067] A glass sheet 6 is embedded on the top surface of the vacuum pouring box 1 and is directly above the cup openings of the pouring cup 3 and the riser cup 4; a camera 7 is provided above the glass sheet 6;

[0068] The camera 7 is a high-resolution color camera, the field of view of the camera 7 is perpendicular to the glass sheet 6, and the field of view of the camera 7 covers the liquid surface of the pouring cup 3 and the riser cup 4;

[0069] The camera 7 is connected to the image processing host 10 via a host connection cable 11 to receive shooting instructions and send the captured images to the image processing host 10 .

[0070] The glass sheet 6 is a bandpass filter tempered glass sheet;

[0071] The bandpass filter tempered glass sheet 6 is a tempered glass with a thickness of 15 mm to 20 mm installed on the original vacuum casting box. The glass surface is coated with a narrow-band filter coating, which allows the wavelength of light to pass through to be between 500 nm and 600 nm. It provides an image acquisition window on the vacuum casting box for the high-resolution color camera to capture the images of the gate and riser liquid level, while ensuring that the vacuum environment in the casting box is not destroyed.

[0072] The high-resolution color camera uses a high-resolution network port camera 7 with a resolution of 2048×1200, 49 frames of images per second, global shutter, exposure time of 4 to 10 microseconds, and a power supply voltage of 12 volts. The lens uses an aperture of F2.8 to F16, H is 49.46°, V is 34.19°, and the installation interface is C port. The high-resolution color camera is responsible for collecting images of the liquid surface of the pouring cup and the riser cup reached by the laser first.

[0073] 2. Laser unit

[0074] The laser unit is connected to the image processing host 10 and is used to receive a start instruction from the image processing host 10 and emit laser to the pouring unit;

[0075] The laser unit comprises: a linear laser light source 8 and a light source controller 9 connected thereto;

[0076] The line laser light source 8 is arranged at the top of the vacuum pouring box 1, and the laser light emitted by the line laser light covers the liquid surface of the pouring cup (3) and the riser cup 4;

[0077] The light source controller 9 is connected to the image processing host 10 and is used to receive instructions from the image processing host 10 and turn on the line laser light source 8 .

[0078] Because the circuit part cannot work in the vacuum box, negative pressure and high temperature environment. Therefore, a special laser light source is used, and the line laser light source 8 and the light source controller 9 are designed separately. The line laser light source 8 uses a 100mw laser tube, the spectrum is 520±10nm, the line laser, the emission angle is 90°, and the light source is waterproof. The power supply part uses 12V power supply, and the connection uses a high temperature resistant cable 12. The function of the line laser light source is to project the laser on the liquid surface of the pouring cup and the riser cup, and use the height difference between the liquid surface and the cup wall to make the line laser bend in the imaging, which indirectly reflects the height difference of the liquid surface.

[0079] 3. Casting unit

[0080] The pouring port controller is connected to the image processing host 10 via a controller cable 13, and the pouring unit is connected to the pouring port controller, and is used to receive the pouring instruction from the image processing host 10 and complete the pouring process according to the automatic judgment rule;

[0081] The pouring unit comprises: a vacuum pouring box 1 and a pouring port 2, a pouring cup 3, a riser cup 4 and a casting mold 5 arranged inside the vacuum pouring box;

[0082] The casting mold 5 is arranged at the center of the vacuum pouring box 1, and a pouring cup 3 and a riser cup 4 are symmetrically arranged at both ends of the top surface of the casting mold 5; the top of the pouring cup 3 corresponds to the pouring material port 2; the top of the riser cup 4 corresponds to the image acquisition unit;

[0083] A laser unit is provided on the top of one side of the vacuum pouring box 1 corresponding to the pouring cup 3;

[0084] The pouring port 2 is connected to the pouring port controller via a cable, and is used to receive control of the pouring port controller to perform pouring operations.

[0085] 4. Image processing host 10

[0086] The image processing host 10 is used to receive the laser-irradiated casting unit liquid surface image, perform image processing operations, and measure the liquid surface height through an image laser line position detection algorithm based on the processed image.

[0087] The image processing host (10) CPU uses an Intel Core i7 6700K processor with four cores and eight threads and a maximum frequency of 4.2GHz, including 32GB 128-bit LPDDR4 memory, 2 DSI interfaces, 2 DP1.2 interfaces / HDMI2.0 interfaces / eDP1.4 interfaces, and 6 network camera interfaces. Its main function is to receive images collected by the camera, calculate the liquid level of the pouring cup and the riser cup, and control the pouring port controller 2 to take corresponding operations.

[0088] The present invention also describes a detection method of a vacuum casting liquid level visual detection device based on a laser light source, comprising the following steps:

[0089] 1) The image processing host 10 turns on the line laser light source 8 through the light source controller 9, and the line laser light source 8 projects the laser line on the liquid surface of the pouring cup 3 and the riser cup 4, and sends a pouring instruction to the pouring gate controller to start injecting raw materials into the pouring cup 3. The feeding speed of the pouring gate 2 is divided into a fast gear and a slow gear. When pouring starts, the pouring gate controller controls the pouring gate 2 to use the fast gear for pouring;

[0090] 2) The image processing host 10 sends a shooting instruction to the camera 7, and at the same time, receives an image from the camera 7 and performs an image processing operation on the image to obtain a processed image;

[0091] 3) Setting the warning line and safety line of the liquid level; the image processing host 10 measures the liquid level according to the processed image by using the image laser line position detection algorithm;

[0092] 4) The image processing host 10 completes the pouring process according to the automatic judgment rules based on the liquid level heights of the pouring cup and the riser cup calculated according to the image;

[0093] 5) When the liquid level at the riser reaches the warning line, pouring is completed.

[0094] like Figure 4 The figure shows the processing flow of the image processing host 10 of the present invention, which is as follows:

[0095] 2-1) Preprocessing the laser line speckle image: performing laser imaging parameter calculation, Gaussian gain coefficient calculation, and adaptive contrast image enhancement operations on the laser line speckle image;

[0096] 2-2) obtaining the position of the laser line breakpoint in the preprocessed image, and performing grayscale expansion operation on the image;

[0097] 2-3) The center coordinates of the laser line in the image are extracted through Gaussian filtering and Hessian matrix transformation.

[0098] like Figure 3a and Figure 3b As shown, the liquid level is measured by the image laser line position detection algorithm, specifically:

[0099] 3-1) Set point A as a point on the laser line when the liquid level is full, point B as a point on the laser line at the current liquid level, and point C as the emission point of the laser light source;

[0100] 3-2) Points A, B, and C form a triangular section, and the height difference h between the current liquid surface and the cup mouth plane is:

[0101] h=tanθ×L

[0102] Wherein, θ is the angle between the laser light source and the liquid surface, and L is the horizontal distance between the laser line when the liquid surface is full and the laser line at the current liquid surface height;

[0103] 3-3) Set A1 as the vertical projection of A, and get the horizontal distance L between the laser line when the liquid level is full and the laser line at the current liquid level, that is:

[0104] L=PL×ε

[0105] Where PL is the number of image pixels between the laser line at full liquid level and the laser line at the current liquid level, ε is the minimum measurement length of the imaging system, and its unit is mm / pixel;

[0106] 3-4) According to step 3-2) to step 3-3), the height difference h between the current liquid surface and the cup mouth plane is:

[0107] h=tanθ×PL×ε

[0108] 3-5) According to the triangle principle, obtain the liquid level U of the pouring cup or riser cup h ,Right now:

[0109] U h =U l -h

[0110] Among them, Ul is the vertical height of the pouring cup or riser cup, U h It is the liquid level height of pouring cup or riser cup.

[0111] Finally, the image host uses the above parameters to complete the automatic control process of pouring liquid level detection. The criteria for judging whether the pouring process is completed are as follows:

[0112] 4-1) When the liquid levels of the pouring cup and the riser cup are both below the safety line, a fast gear injection instruction is sent to the pouring controller;

[0113] 4-2) When the liquid level of the pouring cup or the riser cup is between the safety line and the warning line, a slow gear injection instruction is sent to the pouring controller;

[0114] 4-3) When the liquid level in the pouring cup or riser cup is higher than the warning line, the pouring instruction is sent to the pouring controller to stop.

[0115] After the pouring stops, turn off the system power, remove the pouring workpiece, and complete the pouring.

[0116] In summary, the present invention solves the problem of controlling the pouring liquid level during manual pouring, greatly improves the pouring efficiency, and at the same time reduces the waste of resources caused by material overflow due to inaccurate manual monitoring of the liquid level position and reduces the probability of defective products. The method of calculating the liquid level using a line laser solves the problem of inaccurate calculation caused by the area method used in the existing visual pouring system to indirectly judge the liquid level due to changes in external light, and greatly improves the stability of the automatic visual pouring system. The laser speckle light strip center extraction method can greatly improve the accuracy of liquid level calculation in actual application scenarios, thereby improving the control accuracy of the automatic visual pouring system.

[0117] Those skilled in the art will appreciate that the above are only preferred embodiments of the present invention, and the various embodiments of the present disclosure and / or the features described in the claims may be combined or combined in various ways, even if such combinations or combinations are not explicitly described in the present disclosure. It is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may still modify the technical solutions described in the aforementioned embodiments, or perform equivalent substitutions on some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

[0118] Although preferred embodiments of the present invention have been described, additional changes and modifications may be made to these embodiments by those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A vacuum casting liquid level visual detection device based on laser light source, characterized in that: include: An image processing host (10), a pouring nozzle controller, a pouring unit, a laser unit and an image acquisition unit; The image acquisition unit is arranged directly above the pouring unit and is connected to the image processing host (10) via a host connection cable (11), and is used to receive a shooting instruction and send the collected laser-irradiated liquid surface image of the pouring unit to the image processing host (10) for processing; The laser unit is connected to the image processing host (10) and is used to receive a start instruction from the image processing host (10) and emit laser light to the pouring unit; The pouring port controller is connected to the image processing host (10) via a controller cable (13), and the pouring unit is connected to the pouring port controller, and is used to receive a pouring instruction from the image processing host (10) and complete the pouring process according to an automatic judgment rule; The image processing host (10) is used to receive the laser-irradiated pouring unit liquid surface image, perform image processing operations, and measure the liquid surface height through an image laser line position detection algorithm based on the processed image.

2. According to claim 1, a vacuum casting liquid level visual detection device based on a laser light source is characterized in that: The pouring unit comprises: a vacuum pouring box (1), and a pouring port (2), a pouring cup (3), a riser cup (4) and a casting mold (5) arranged inside the vacuum pouring box; The casting mold (5) is arranged at the center of the vacuum pouring box (1), and a pouring cup (3) and a riser cup (4) are symmetrically arranged at two ends of the top surface of the casting mold (5); the top of the pouring cup (3) corresponds to the pouring material port (2); the top of the riser cup (4) corresponds to the image acquisition unit; A laser unit is provided on the top of one side of the vacuum pouring box (1) corresponding to the pouring cup (3); The pouring port (2) is connected to a pouring port controller via a cable and is used to receive control of the pouring port controller to perform pouring operations.

3. The vacuum casting liquid level visual detection device based on laser light source according to claim 1 is characterized in that: The image acquisition unit comprises: a glass sheet (6) and a camera (7); The glass sheet (6) is embedded on the top surface of the vacuum pouring box (1) and is directly above the cup openings of the pouring cup (3) and the riser cup (4); a camera (7) is provided above the glass sheet (6); The camera (7) is a high-resolution color camera, the field of view of the camera (7) is perpendicular to the glass sheet (6), and the field of view of the camera (7) covers the liquid surface of the pouring cup (3) and the riser cup (4); The camera (7) is connected to the image processing host (10) via a host connection cable (11) to receive a shooting instruction and send the captured image to the image processing host (10).

4. The vacuum casting liquid level visual detection device based on laser light source according to claim 1 is characterized in that: The glass sheet (6) is a bandpass filtering tempered glass sheet; The thickness of the glass sheet (6) is 15 mm to 20 mm; the surface of the glass sheet (6) is coated with a narrow-band filter coating, which allows the wavelength of light to pass through to be between 500 nm and 600 nm.

5. The vacuum casting liquid level visual detection device based on laser light source according to claim 1 is characterized in that: The laser unit comprises: a linear laser light source (8) and a light source controller (9) connected thereto; The line laser light source (8) is arranged at the top of the vacuum pouring box (1), and the laser light emitted by the line laser light covers the liquid surface of the pouring cup (3) and the riser cup (4); The light source controller (9) is connected to the image processing host (10) and is used to receive instructions from the image processing host (10) and turn on the line laser light source (8).

6. The detection method of a vacuum casting liquid level visual detection device based on a laser light source according to claim 1 is characterized in that: The following steps are involved: 1) The image processing host (10) turns on the line laser light source (8) through the light source controller (9), and the line laser light source (8) projects a laser line onto the liquid surface of the pouring cup (3) and the riser cup (4), and sends a pouring instruction to the pouring gate controller to start injecting raw materials into the pouring cup (3). The feeding speed of the pouring gate (2) is divided into a fast gear and a slow gear. When pouring starts, the pouring gate controller controls the pouring gate (2) to use the fast gear for pouring; 2) The image processing host (10) sends a shooting instruction to the camera (7), and at the same time, receives an image from the camera (7), and performs an image processing operation on the image to obtain a processed image; 3) setting a warning line and a safety line for the liquid level; the image processing host (10) measures the liquid level according to the processed image by using an image laser line position detection algorithm; 4) The image processing host (10) completes the pouring process according to the automatic judgment rules based on the liquid level heights of the pouring cup and the riser cup calculated from the image; 5) When the liquid level at the riser reaches the warning line, pouring is completed.

7. The detection method of the vacuum pouring liquid level visual detection device based on laser light source according to claim 6 is characterized in that: The step 2) is specifically: 2-1) Preprocessing the laser line speckle image: performing laser imaging parameter calculation, Gaussian gain coefficient calculation, and adaptive contrast image enhancement operations on the laser line speckle image; 2-2) obtaining the position of the laser line breakpoint in the preprocessed image, and performing grayscale expansion operation on the image; 2-3) The center coordinates of the laser line in the image are extracted through Gaussian filtering and Hessian matrix transformation.

8. The detection method of the vacuum pouring liquid level visual detection device based on laser light source according to claim 6 is characterized in that: The liquid level is measured by the image laser line position detection algorithm, specifically: 3-1) Set point A as a point on the laser line when the liquid level is full, point B as a point on the laser line at the current liquid level, and point C as the emission point of the laser light source; 3-2) Points A, B, and C form a triangular section, and the height difference h between the current liquid surface and the cup mouth plane is: h=tanθ×L Wherein, θ is the angle between the laser light source and the liquid surface, and L is the horizontal distance between the laser line when the liquid surface is full and the laser line at the current liquid surface height; 3-3) Set A1 as the vertical projection of A, and get the horizontal distance L between the laser line when the liquid level is full and the laser line at the current liquid level, that is: L=PL×ε Where PL is the number of image pixels between the laser line at full liquid level and the laser line at the current liquid level, ε is the minimum measurement length of the imaging system, and its unit is mm / pixel; 3-4) According to step 3-2) to step 3-3), the height difference h between the current liquid surface and the cup mouth plane is: h=tanθ×PL×ε 3-5) According to the triangle principle, obtain the liquid level U of the pouring cup or riser cup h ,Right now: U h =U l -h Among them, U l is the vertical height of the pouring cup or riser cup, U h It is the liquid level height of pouring cup or riser cup.

9. The detection method of the vacuum pouring liquid level visual detection device based on laser light source according to claim 6 is characterized in that: The pouring process is completed according to the automatic judgment rule, specifically: 4-1) When the liquid levels of the pouring cup and the riser cup are both below the safety line, a fast gear injection instruction is sent to the pouring controller; 4-2) When the liquid level of the pouring cup or the riser cup is between the safety line and the warning line, a slow gear injection instruction is sent to the pouring controller; 4-3) When the liquid level in the pouring cup or riser cup is higher than the warning line, the pouring instruction is sent to the pouring controller to stop.

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