Spraying pipe throat measuring method and device

Abstract

The invention discloses a nozzle throat measuring method and device, and relates to the technical field of machining manufacturing and optical measurement, and the method comprises the steps: obtaining an edge image of a to-be-detected region in a to-be-detected nozzle throat; performing size calibration on the to-be-detected area to obtain a reference proportionality coefficient of the size data of the edge image of the to-be-detected area and the standard scale data of the to-be-detected area; calculating the area of the to-be-detected region based on the edge image to obtain image area data of the to-be-detected region; and determining the throat diameter of the to-be-detected nozzle according to the reference proportionality coefficient and the image area data of the to-be-detected region. According to the invention, the obtained edge image is calibrated to obtain the reference proportionality coefficient, and the image area data of the to-be-detected area is calculated to quickly obtain the throat diameter of the to-be-detected nozzle, so that the test precision and the detection efficiency are greatly improved.

Description

Technical Field

[0001] This application relates to the technical fields of machining manufacturing and optical measurement, and more specifically, to a method and device for measuring the throat of a nozzle. Background Art

[0002] Measuring the throat diameter of a nozzle after a solid rocket motor test is a necessary step in the post-test processing of a solid rocket motor. Accurately measuring the throat diameter of a nozzle is of great significance for analyzing the working performance of a solid rocket motor.

[0003] Currently, after a solid rocket motor test, the throat diameter of the nozzle is usually directly measured using methods such as vernier calipers, micrometers, and standard sample columns for the diameter dimension.

[0004] However, this method has many problems. For example, after a solid rocket motor test, the throat cross-section of the nozzle is an irregular circle, and the diameter measurement results in different directions vary greatly, resulting in low accuracy and large scatter of the test results. In addition, the nozzle of a small solid rocket motor has a small size and a large expansion ratio, and the throat cross-section is located in the deep part where the convergent section and the divergent section of the nozzle are combined, making it difficult to directly measure using conventional means. Summary of the Invention

[0005] In view of at least one defect or improvement requirement of the prior art, the present invention provides a nozzle throat measurement device applicable to measuring the throat of a nozzle after a small solid rocket motor test, so as to solve the problem in the prior art that it is impossible to accurately and quickly measure the throat diameter of a nozzle after a small solid rocket motor test.

[0006] To achieve the above object, according to the first aspect of the present invention, a method for measuring the throat of a nozzle is provided, including:

[0007] Obtaining an edge image of a region to be detected inside the throat of a nozzle to be detected;

[0008] Calibrating the size of the region to be detected to obtain a reference scale factor between the size data of the edge image of the region to be detected and the standard scale data of the region to be detected;

[0009] Calculating the area of the region to be detected based on the edge image to obtain the image area data of the region to be detected;

[0010] Determining the throat diameter of the nozzle to be detected according to the reference scale factor and the image area data of the region to be detected.

[0011] For the method for measuring the throat of a nozzle as described above, the step of obtaining an edge image of a region to be detected inside the throat of a nozzle to be detected includes:

[0012] Obtaining an image of the region to be detected in the throat of the nozzle to be detected;

[0013] Process the image of the area to be detected using a gradient-based regional edge detection algorithm to obtain the edge point set information of the contour of the area to be detected;

[0014] Perform curve fitting on the edge points of the image of the area to be detected in the edge point set information to obtain the edge image of the area to be detected.

[0015] As described in the nozzle throat measurement method, the step of processing the image of the area to be detected using a gradient-based regional edge detection algorithm to obtain the edge point set information of the contour of the area to be detected includes:

[0016] Perform binarization processing on the edge of the image of the area to be detected to obtain the grayscale image of the area to be detected;

[0017] Calculate the gradient value of each pixel point in the grayscale image, and perform non-maximum suppression processing on the gradient value with the maximum gradient amplitude as the target to obtain the processed pixel point set;

[0018] Perform threshold processing on the processed pixel point set to obtain the updated grayscale image;

[0019] Convert the updated grayscale image into a binary image to obtain the edge point set information of the contour of the area to be detected.

[0020] As described in the nozzle throat measurement method, the step of standard scale calibration includes:

[0021] Obtain the standard scale data of the area to be detected and the size data of the edge image of the area to be detected;

[0022] Calculate based on the standard scale data of the area to be detected and the size data of the edge image of the area to be detected to obtain the reference scale factor.

[0023] As described in the nozzle throat measurement method, calculate the area of the area to be detected in the edge image by the rectangular numerical integration method.

[0024] As described in the nozzle throat measurement method, the step of determining the diameter of the nozzle throat to be detected according to the reference scale factor and the image area data of the area to be detected includes:

[0025] Calculate the diameter of the nozzle throat to be detected by using the area equivalent algorithm based on the reference scale factor for the image area data of the area to be detected.

[0026] As described in the nozzle throat measurement method, before processing the image of the area to be detected using a gradient-based regional edge detection algorithm, it also includes: preprocessing the image of the area to be detected, and the specific steps of the preprocessing include:

[0027] Traverse each pixel in the image, define a window centered on the current pixel, flatten the window into a column vector, and sort the column vector to obtain a sorted window;

[0028] Calculate the average value based on the sorted window, and assign this average value to the corresponding current pixel in the image of the area to be detected.

[0029] According to the second aspect of the present invention, there is also provided a nozzle throat measurement device, including: a device main body 1, a stage 2 provided on the device main body, a detection mechanism 3, and a host computer 6;

[0030] The detection mechanism 3 is arranged above the stage 2; a calibration component 5 is further provided on the stage 2 for performing dimension calibration; and a light source 4 is further provided on the stage 2 or the calibration component 5 for irradiating the stage 2, and the host computer 6 is communicatively connected to the detection mechanism 3 for executing the nozzle throat measurement method of any one of the above.

[0031] According to the third aspect of the present invention, there is also provided a nozzle throat measurement device, which includes at least one processing unit and at least one storage unit, wherein the storage unit stores a computer program, and when the computer program is executed by the processing unit, the processing unit is enabled to execute the steps of the nozzle throat measurement method of any one of the above.

[0032] According to the fourth aspect of the present invention, there is also provided a storage medium, which stores a computer program executable by an access authentication device, and when the computer program runs on the access authentication device, the nozzle throat measurement device is enabled to execute the steps of the method of any one of the above.

[0033] Generally speaking, compared with the prior art, the above technical solutions conceived by the present invention can achieve the following beneficial effects:

[0034] The present invention obtains the edge image of the area to be detected inside the nozzle throat to be detected, performs dimension calibration on the area to be detected to obtain the reference proportional coefficient between the dimension data of the edge image of the area to be detected and the standard scale data of the area to be detected, and then calculates the area of the area to be detected based on the edge image to obtain the image area data of the area to be detected; thus, according to the reference proportional coefficient and the image area data of the area to be detected, the diameter of the nozzle throat to be detected is determined. The present invention obtains the reference proportional coefficient by performing calibration processing on the acquired edge image, and then calculates the image area data of the area to be detected, so that the diameter of the nozzle throat to be detected can be quickly obtained, greatly improving the test accuracy and detection efficiency.

[0035] The nozzle throat measurement device provided by the present invention realizes the rapid measurement of relevant parameters of the nozzle candidate after rapid testing through the combined design of the device main body, the loading platform provided on the device main body, and the detection mechanism, as well as the adjustable setting of the light source provided on the loading platform or the calibration component in cooperation with the detection mechanism. It has the advantages of convenient operation, high test accuracy, and process automation. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0037] Figure 1 FIG. is a schematic structural diagram of a nozzle throat measurement device provided by an embodiment of the present application;

[0038] Figure 2 FIG. is a schematic flowchart of a nozzle throat measurement method provided by an embodiment of the present application;

[0039] Figure 3 FIG. is a schematic diagram of the edge image of the area to be detected at the nozzle throat after the solid rocket motor test provided by an embodiment of the present application;

[0040] Figure 4 FIG. is a schematic structural diagram of an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0041] In order to make the purpose, technical solutions and advantages of the present invention clearer, the following further describes the present invention in detail with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0042] The terms "first", "second", "third", etc. in the specification, claims and drawings of the present application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally further include steps or units not listed, or may optionally further include other steps or units inherent to these processes, methods, products or devices.

[0043] The following will be combined with Figures 1-4Describe a nozzle throat measurement method and device provided by an embodiment of the present invention.

[0044] Figure 1 It is a schematic structural diagram of a nozzle throat measurement device provided by an embodiment of the present invention. As Figure 1 shown, the nozzle throat measurement device includes a device main body 1, a carrier table 2, a detection mechanism 3, and a host computer 6 provided on the device main body; the detection mechanism 3 is arranged above the carrier table 2; a calibration component 5 is further provided on the carrier table 2 for size calibration; and a light source 4 is further provided on the carrier table 2 or the calibration component 5 for irradiating the carrier table 2, and the host computer 6 is communicatively connected to the detection mechanism 3.

[0045] As a preferred embodiment of the present application, the device main body 1 can be a three-dimensional adjustable mechanical platform, the detection mechanism 3 can be a zoom camera arranged at an interval from the carrier table 2, and the calibration component 5 can be an adjustable calibration ruler.

[0046] For a nozzle throat measurement device provided by an embodiment of the present invention, when measuring the nozzle throat to be detected after the test, first, place the nozzle after the solid rocket motor test to be measured on the carrier table 2, and adjust the relative positions of the nozzle throat to be detected after the test and the detection mechanism 3 up, down, left, right, front, and back through the device main body 1.

[0047] Optionally, the carrier table 2 is internally provided with a light source, and the light source brightness can be adjusted to make the image light obtained by the detection mechanism 3 good, so as to improve the imaging quality.

[0048] During operation, fix the nozzle to be detected reliably, and the nozzle axis is perpendicular to both the carrier table 2 and the lens of the detection mechanism 3 at the same time, ensuring that the throat diameter section can be photographed in the direction of the nozzle axis, reducing the image deformation to the minimum, and ensuring that the smallest effective throat diameter section can be obtained.

[0049] Set the focal length and magnification of the detection mechanism 3, finely adjust the device main body 1 to make the image obtained by the detection mechanism 3 clear, adjust the standard scale of the calibration component 5 to be in a suitable position in the image, collect the image information of the nozzle throat through the detection mechanism 3, and transmit it to the host computer 6 through a digital interface, and the host computer 6 performs analysis and processing.

[0050] A nozzle throat measurement device provided by the present invention for measuring the nozzle throat after a small solid rocket motor test has the advantages of convenient operation, high test accuracy, and automatic process.

[0051] Figure 2 It is a schematic flow diagram of a nozzle throat measurement method provided by the present invention. As Figure 1 shown, it includes but is not limited to the following steps:

[0052] Step 101: Obtain the edge image of the area to be detected inside the nozzle throat to be detected.

[0053] As Figure 2 shown, in this embodiment, the edge image of the area to be detected on the nozzle after the solid rocket motor test is obtained through the above nozzle throat measurement device; Figure 3 is a schematic diagram of the edge image of the area to be detected at the nozzle throat after the solid rocket motor test provided by the present invention. It should be noted that the area to be detected can be the nozzle throat after the solid rocket motor test, or other irregular geometric graphic areas similar to the cross-section of the nozzle throat after the engine test. The edge image is the image information of the contour to be measured in the area to be detected.

[0054] Based on the content of the above embodiment, as an alternative embodiment, in the nozzle throat measurement method provided by the present invention, the step of obtaining the edge image of the area to be detected includes:

[0055] Obtain the image of the area to be detected at the nozzle throat; process the image of the area to be detected using a gradient-based region edge detection algorithm to obtain the edge point set information of the contour of the area to be detected, and perform curve fitting on the edge points of the image of the area to be detected in the edge point set information to obtain the edge image.

[0056] The image of the area to be detected is a picture of the area to be detected of the object to be detected taken by a detection device such as a zoom camera.

[0057] In this embodiment, the step of obtaining the image of the area to be detected at the nozzle throat includes: traversing each pixel in the original image of the area to be detected, defining a window centered on the current pixel, flattening the window into a column vector, sorting the vector and calculating the average value, and assigning this average value to the corresponding pixel in the output image to obtain the image of the area to be detected.

[0058] Optionally, preprocess the image of the area to be detected. The preprocessing steps include, for example, noise removal, enhancement, median filtering, etc.

[0059] In one embodiment, traversing each pixel in the original image includes: for i = 1 to m, j = 1 to n; in the padded image, define a window centered on the current pixel: windows = padded Image(i:i+windowsSize-1,j:j+windowSize-1);

[0060] Flatten the window into a column vector and sort the values: sorted Windows = sort(window(:));

[0061] Calculate the median value from the sorted window: median Value = sorted Window((windowSize^2+1) / 2);

[0062] Assign the median value to the corresponding pixel in the output image: filter_red_Image(i, j) = median_Value;

[0063] After processing all pixels, the filtered Image will contain the result of median filtering.

[0064] Where: image is the input image matrix of size m x n, window_Size is the window size used for median filtering, pad_Size is the padding size calculated by the padarray function; padded_Image is the image matrix after symmetric padding, and filtered_Image is the output matrix with the same size as the input image.

[0065] Furthermore, based on the content of the above embodiments, as an alternative embodiment, in the nozzle throat measurement method provided by the present invention, the step of processing the image of the area to be detected by using a gradient-based region edge detection algorithm to obtain the edge point set information of the contour of the area to be detected includes:

[0066] Perform binarization processing on the edge of the image of the area to be detected to obtain the grayscale image of the area to be detected;

[0067] Calculate the gradient value of each pixel point in the grayscale image, and perform non-maximum suppression processing on the gradient value with the maximum gradient amplitude as the target to obtain the processed pixel point set;

[0068] Perform threshold processing on the processed pixel point set to obtain the updated grayscale image;

[0069] Convert the updated grayscale image into a binary image to obtain the edge point set information of the contour of the area to be detected.

[0070] Specifically, for the image of the area to be detected, first convert the color image into a grayscale image; then calculate the gradient value of each pixel point in the grayscale image, and then perform non-maximum value suppression processing on the calculated gradient value to retain the pixel points with the maximum gradient amplitude; further perform threshold processing on the pixel points, and then convert the grayscale image into a binary image; finally, connect the edge points of the image of the area to be detected, extract the edge information of the contour of the area to be measured, and perform curve fitting on the edge points to obtain the edge image. Furthermore, extract the contour information (Contour Extraction), and extract the edge information of the contour of the area to be detected by connecting the edge points.

[0071] Among them, the steps of extracting the edge information of the contour of the area to be detected include: finding the first boundary starting point I0 that has not marked the end of tracking. This point should have the smallest row value and the smallest column value. Define a scanning direction variable 'dir' to record the moving direction from the previous boundary point to the current boundary point.

[0072] Furthermore, initialize the current point as the starting point I0, create an empty contour variable to store the contour points. Scan the image from top to bottom and from left to right, and proceed as follows: Determine the 8 adjacent pixels around the current point (upper left, upper, upper right, left, right, lower left, lower, lower right), find the adjacent point with the smallest row value and the smallest column value as the next boundary point, update the current point to the newly found boundary point, and add it to the contour. Update the scanning direction variable 'dir' to record the moving direction from the previous boundary point to the current boundary point. Repeat these steps until there are no available adjacent pixels, indicating the end of the contour scan.

[0073] Step 102: Calibrate the size of the area to be detected to obtain the reference ratio coefficient between the size data of the edge image of the area to be detected and the standard scale data of the area to be detected.

[0074] Obtain the standard scale data of the area to be detected and the size data of the edge image of the area to be detected, and calculate the reference ratio coefficient by dividing the known distance of the standard scale data of the reference scale by the measured distance on the pixels of the edge image of the area to be detected. The reference ratio coefficient is the ratio coefficient between the standard scale data of the area to be detected and the size data of the edge image of the area to be detected. Among them, the ratio coefficient can be obtained by acquiring the actual international length unit value of each pixel, and then through comparison with the standard scale data, the ratio coefficient is obtained.

[0075] Optionally, during the process of measuring the area to be detected using, for example, the above-mentioned throat measurement device, use the data on the calibration component 5 as the true reference size. The standard scale information provided by the calibration component 5 is included in the image output by the host computer 6, and the ratio coefficient is calculated by dividing the standard scale distance of the calibration component 5 by the measured test distance in the image, thereby realizing the calibration process of the image size.

[0076] Specifically, the operation process is as follows:

[0077] 1. Ensure that the height calibration component 5 and the nozzle sample to be detected are placed on the stage 2 at the same time (do not move before the measurement ends).

[0078] 2. When the stage 2 is adjusted to move horizontally forward, backward, left, and right, the scale of the calibration component 5 and the outer contour pattern of the throat diameter cross-section can be observed simultaneously in the real-time output image of the host computer 6.

[0079] 3. Open the grid division lines of the host computer image processing software, and use the caliper tool in the image processing software to measure the known distances on the reference dimensions. This includes placing the measurement points of the caliper on two points of the reference scale of the calibration component 5 and recording the measured distances.

[0080] It should be noted that during operation, the real-time obtained throat diameter cross-sectional image can be observed through the host computer, and then the camera lens can be adjusted. Under the condition of ensuring that the complete image of the cross-sectional outer contour is fully displayed on the screen, the magnification of the camera can be increased as much as possible, and at the same time, the focus can be adjusted (allowing the height of the stage to be adjusted simultaneously) to ensure that the image is clear and convenient for observation.

[0081] At the same time, under the condition of ensuring the accurate acquisition of the throat diameter cross-sectional outer contour pattern, the horizontal height of the adjustable calibration ruler can be adjusted to ensure that the horizontal height of the calibration ruler is consistent with the horizontal height of the maximum cross-sectional diameter of the throat diameter on the stage (they are consistent with the effective observation distance of the camera).

[0082] In this embodiment, the scale factor is calculated by dividing the standard scale distance of the calibration component 5 by the measured test distance in the image.

[0083] This will give the actual international length unit value of each pixel. Then, by comparing with the standard scale, the calculated scale factor is obtained to obtain the reference scale factor between the size data of the edge image of the area to be detected and the standard scale data of the area to be detected.

[0084] Step 103: Calculate the area of the area to be detected based on the edge image to obtain the image area data of the area to be detected.

[0085] For the area to be detected on the edge image, image processing algorithms such as image segmentation algorithms, connected region analysis, or scan line algorithms are used to calculate the area, so as to obtain the area of the area to be detected.

[0086] Optionally, image segmentation algorithms such as threshold segmentation, edge detection, region growing, etc. are used to separate the area to be detected from the background, and then processing such as filtering, smoothing, edge detection, etc. is performed to obtain the area of the area to be detected.

[0087] Optionally, the scan line algorithm is used to scan the area to be detected along the scan line, calculate the area of each pixel point, and then perform processing such as filtering, smoothing, edge detection, etc. to obtain the area of the area to be detected. This method usually requires the use of image processing techniques such as filtering, smoothing, edge detection, etc.

[0088] Optionally, a connected region analysis method based on the edge image is adopted for area calculation. Specifically, an edge detection algorithm (such as the Canny algorithm) can be used to preprocess the edge image, and then a connected region analysis algorithm (such as the labeling matrix method) is used to separate the connected regions in the region to be detected and calculate the sum of their areas. This method can take into account the connected regions around the nozzle throat, so it can calculate the area of the region to be detected in the nozzle throat cross-section more accurately.

[0089] It should be noted that different area calculation methods are applicable to different scenarios and data, and appropriate methods need to be selected according to the actual situation. At the same time, when calculating the area, it is also necessary to consider the influence of factors such as image noise and distortion on the results, and perform appropriate preprocessing and correction.

[0090] Based on the content of the above embodiments, as an alternative embodiment, in the nozzle throat measurement method provided by the present invention, the area of the region to be detected in the edge image is calculated by the rectangular numerical integration method.

[0091] The rectangular numerical integration method is applied to calculate the area of the region surrounded by the edge image, specifically: the region to be detected in the edge image is two-dimensionally meshed, and the region to be detected is divided into several small unit rectangular regions. It is judged whether the image in each small unit rectangular region is within the detection edge range. If so, this rectangular region is included in the calculated area; otherwise, it is not included. The total calculated area obtained after traversing all the small unit rectangular regions is the image area data of the region to be detected.

[0092] Step 104: The step of determining the diameter of the nozzle throat to be detected according to the reference scale factor and the image area data of the region to be detected includes: calculating the diameter of the nozzle throat to be detected by using the area equivalent algorithm based on the reference scale factor for the image area data of the region to be detected.

[0093] In this embodiment, according to the area equivalent principle, the diameter of the nozzle throat to be detected is calculated from the area of the detected nozzle throat according to the area calculation formula of a circle.

[0094] Based on the content of the above embodiments, as an alternative embodiment, before processing the image of the region to be detected by using the gradient-based region edge detection algorithm in the nozzle throat measurement method provided by the present invention, it further includes: preprocessing the image of the region to be detected, and the specific steps of the preprocessing include:

[0095] Traverse each pixel in the image, define a window centered on the current pixel, flatten the window into a column vector, and sort the column vector to obtain the sorted window;

[0096] Calculate the average value based on the sorted window and assign this average value to the corresponding current pixel in the image of the area to be detected.

[0097] Specifically, before performing edge detection on the image of the area to be detected, it is necessary to consider the influence of factors such as image noise and distortion on the results, and usually appropriate preprocessing and correction are required.

[0098] In this embodiment, the preprocessing includes noise removal, enhancement, median filtering, etc.

[0099] Preferably, the preprocessing includes traversing each pixel in the original image of the area to be detected, defining a window centered on the current pixel, flattening the window into a column vector, sorting the vector and calculating the average value, and assigning this average value to the corresponding pixel in the output image.

[0100] Traverse each pixel in the original image: for i = 1 to m, j = 1 to n; in the padded image, define a window centered on the current pixel: windows = padded Image(i:i+windowsSize-1,j:j+windowSize-1);

[0101] Flatten the window into a column vector and sort the values: sorted Windows = sort(window(:));

[0102] Calculate the median value from the sorted window: median Value = sorted Window((windowSize^2+1) / 2);

[0103] Assign the median value to the corresponding pixel in the output image: filter red Image(i,j) = median Value;

[0104] After processing all pixels, the filtered Image will contain the result of median filtering to obtain the preprocessed image of the area to be detected.

[0105] Where: image is the input image matrix of size m x n, window Size is the window size for median filtering, pad Size is the padding size calculated by the padarray function; padded Image is the image matrix after symmetric padding, and filtered Image is the output matrix with the same size as the input image.

[0106] Figure 4 is the structural schematic diagram of the electronic device provided by the present invention, as Figure 4As shown in the figure, the electronic device may include: a processor 410, a communications interface 420, a memory 430, and a communication bus 440. Among them, the processor 410, the communications interface 420, and the memory 430 communicate with each other through the communication bus 440. The processor 410 can call the logical instructions in the memory 430 to execute the nozzle throat measurement method, including: obtaining an edge image of the area to be detected inside the nozzle throat to be detected; calibrating the size of the area to be detected to obtain a reference proportionality coefficient between the size data of the edge image of the area to be detected and the standard scale data of the area to be detected; calculating the area of the area to be detected based on the edge image to obtain the image area data of the area to be detected; and determining the diameter of the nozzle throat to be detected according to the reference proportionality coefficient and the image area data of the area to be detected.

[0107] In addition, when the logical instructions in the above-mentioned memory 430 are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs that can store program codes.

[0108] On the other hand, the present invention also provides a computer program product. The computer program product includes a computer program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute a nozzle throat measurement method provided in each of the above embodiments, including: obtaining an edge image of the area to be detected inside the nozzle throat to be detected; calibrating the size of the area to be detected to obtain a reference proportionality coefficient between the size data of the edge image of the area to be detected and the standard scale data of the area to be detected; calculating the area of the area to be detected based on the edge image to obtain the image area data of the area to be detected; and determining the diameter of the nozzle throat to be detected according to the reference proportionality coefficient and the image area data of the area to be detected.

[0109] In another aspect, the present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, it implements a nozzle throat measurement method provided in each of the above embodiments, including: acquiring an edge image of a to-be-detected area inside a to-be-detected nozzle throat; calibrating the size of the to-be-detected area to obtain a reference scale factor between the size data of the edge image of the to-be-detected area and the standard scale data of the to-be-detected area; calculating the area of the to-be-detected area based on the edge image to obtain image area data of the to-be-detected area; and determining the diameter of the to-be-detected nozzle throat according to the reference scale factor and the image area data of the to-be-detected area.

[0110] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. A person of ordinary skill in the art can understand and implement it without creative labor.

[0111] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution, in essence, or the part that contributes to the prior art can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disc, etc., and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0112] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A nozzle throat measurement method, characterized in that: include: Acquire an edge image of the area to be inspected in the throat of the nozzle to be inspected; Calibrate the size of the area to be detected to obtain a reference ratio coefficient between the size data of the edge image of the area to be detected and the standard scale data of the area to be detected; Calculate the area of ​​the area to be detected based on the edge image to obtain image area data of the area to be detected; The diameter of the nozzle throat to be inspected is determined according to the reference proportionality coefficient and the image area data of the area to be inspected.

2. The nozzle throat measurement method according to claim 1, characterized in that: The step of obtaining an edge image of the area to be detected in the throat of the nozzle to be detected comprises: Acquire an image of the area to be inspected of the nozzle throat to be inspected; The image of the area to be detected is processed by using a gradient-based area edge detection algorithm to obtain edge point set information of the contour of the area to be detected; Curve fitting is performed on the edge points of the image of the area to be detected in the edge point set information to obtain an edge image of the area to be detected.

3. The nozzle throat measurement method according to claim 2, characterized in that: The step of processing the image of the area to be detected by using a gradient-based area edge detection algorithm to obtain edge point set information of the contour of the area to be detected comprises: Binarization is performed on the edge of the image of the area to be detected to obtain a grayscale image of the area to be detected; Calculating the gradient value of each pixel in the grayscale image, and performing non-maximum suppression processing on the gradient value with the goal of maximizing the gradient amplitude, to obtain a processed pixel point set; Performing threshold processing on the processed pixel point set to obtain an updated grayscale image; The updated grayscale image is converted into a binary image to obtain edge point set information of the contour of the area to be detected.

4. The nozzle throat measurement method according to claim 1, characterized in that: The steps of standard scale calibration include: Obtaining standard scale data of the area to be detected and size data of the edge image of the area to be detected; A reference scale coefficient is obtained by performing calculation based on the standard scale data of the area to be detected and the size data of the edge image of the area to be detected.

5. The nozzle throat measurement method according to claim 1, characterized in that: The area of ​​the region to be detected is calculated for the edge image using a rectangular numerical integration method.

6. The nozzle throat measurement method according to claim 1, characterized in that: The step of determining the nozzle throat diameter to be detected based on the reference scale factor and the image area data of the area to be detected comprises: Based on the reference proportionality coefficient, the image area data of the area to be detected is calculated using an area equivalent algorithm to obtain the nozzle throat diameter to be detected.

7. The nozzle throat measurement method according to claim 2, characterized in that: Before the image of the region to be detected is processed by the gradient-based region edge detection algorithm, the method further includes: preprocessing the image of the region to be detected, wherein the specific steps of the preprocessing include: Traverse each pixel in the image, define a window with the current pixel as the center, flatten the window into a column vector, and sort the column vector to obtain a sorted window; An average value is calculated based on the sorted window, and the average value is assigned to the corresponding current pixel in the image of the area to be detected.

8. A nozzle throat measurement device, characterized in that: include: A device body (1), a loading platform (2) and a detection mechanism (3) arranged on the device body, and a host computer (6); The detection mechanism (3) is arranged above the stage (2); the stage (2) is also provided with a calibration component (5) for dimensional calibration; and the stage (2) or the calibration component (5) is also provided with a light source (4) for illuminating the stage (2), and the host computer (6) is communicatively connected with the detection mechanism (3) for executing the nozzle throat measurement method of any one of claims 1 to 7.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the computer program, the steps of the nozzle throat measurement method according to any one of claims 1 to 7 are implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the nozzle throat measurement method according to any one of claims 1 to 7 are implemented.

Images