Industrial computed tomography method, control terminal and scanning system

Abstract

The application provides an industrial computer tomography method, a control terminal and a scanning system. The method comprises the following steps: acquiring a first projection image and a second projection image when a rotating table is at a first rotation angle and a second rotation angle, and determining a first pixel value and a second pixel value; determining a first X distance and a first Y distance according to the first pixel value, the second pixel value, a number of projection image pixel matrix rows, a detector distance, a rotating table distance and a unit pixel size; determining a second X distance and a second Y distance of multiple subsequent rotations according to the first X distance, the first Y distance and a rotation number; controlling the rotating table to perform a first rotation and controlling a machine table to scan according to the first X distance and the first Y distance; and controlling the rotating table to perform each subsequent rotation and controlling the machine table to scan based on the second X distance and the second Y distance corresponding to each rotation in the multiple subsequent rotations. The application efficiently and conveniently obtains a clear scanning image by pre-calculating the rotating table movement distance and controlling the rotating table movement.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tomography, in particular to an industrial computed tomography method, a control terminal and a scanning system. BACKGROUND

[0002] Industrial computed tomography (CT) technology is one of the core technologies in the field of non-destructive testing. It is widely used in high-end manufacturing industries such as aerospace, automobile manufacturing and medical devices due to its high-resolution imaging capability of internal structures of samples, for detecting defects, size accuracy and assembly consistency inside the samples. At present, the key means for high-precision detection of small precision parts is usually to use fine cone beam scanning technology. In the fine cone beam scanning process, in order to ensure that the imaging of the region of interest is clear and the resolution meets the standard, the region of interest needs to be strictly placed at the center of rotation of the device.

[0003] In the prior art, when the industrial CT device detects samples in the fine cone beam scanning mode, the device is manually adjusted by the staff so that the region of interest is always located at the center of rotation of the device during the detection process.

[0004] However, this manual adjustment method is low in efficiency, high in time cost, and requires high precision of human eye observation and stability of operation method of the staff, which leads to a sharp increase in the failure rate and increases the detection cost. SUMMARY

[0005] The present application aims to solve the problems of low efficiency and high failure rate in the prior art by providing an industrial computed tomography method, a control terminal and a scanning system.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the present application is as follows:

[0007] In a first aspect, the present application provides an industrial computed tomography method, which is applied to a control terminal in a scanning system, the scanning system comprising the control terminal, a radiation source, a turntable and a detector, the turntable being used to place a measured sample, and the method comprising:

[0008] acquiring a first projection image of the measured sample sent by the detector when the turntable is at a first rotation angle, and determining the X-axis coordinate pixel value of the region of interest in the first projection image to obtain a first pixel value; acquiring a second projection image of the measured sample sent by the detector when the turntable is at a second rotation angle, and determining the X-axis coordinate pixel value of the region of interest in the second projection image to obtain a second pixel value;

[0009] determining a first X distance and a first Y distance of a first movement before a first rotation according to the first pixel value, the second pixel value, a preset number of pixel matrixes of a projection image, a detector distance from the ray source to the detector, a turntable distance from the ray source to the turntable, and a unit pixel size;

[0010] determining a second X distance and a second Y distance of each movement before a rotation in a plurality of subsequent rotations according to the first X distance, the first Y distance, and a preset number of rotations;

[0011] controlling the turntable to perform each rotation in the plurality of subsequent rotations and controlling the machine table to scan according to the corresponding second X distance and the second Y distance of each rotation in the plurality of subsequent rotations.

[0012] Optionally, the determining the first X distance and the first Y distance of the first movement before the first rotation according to the first pixel value, the second pixel value, the preset number of pixel matrixes of the projection image, the detector distance from the ray source to the detector, the turntable distance from the ray source to the turntable, and the unit pixel size comprises:

[0013] determining a first actual distance and a second actual distance according to the first pixel value, the second pixel value, the number of pixel matrixes of the projection image, and the unit pixel size, the first actual distance being a distance between a region of interest on a plane where the detector is located and a horizontal direction of a detection center when the turntable is at a first rotation angle, and the second actual distance being a distance between the region of interest on the plane where the detector is located and a vertical direction of the detection center when the turntable is at a second rotation angle;

[0014] determining the first X distance and the first Y distance according to the first actual distance, the second actual distance, the detector distance, and the turntable distance.

[0015] Optionally, the determining the first actual distance and the second actual distance according to the first pixel value, the second pixel value, the number of pixel matrixes of the projection image, and the unit pixel size comprises:

[0016] taking a difference between the first pixel value and half of the number of pixel matrixes of the projection image as a first difference, and taking a product of the first difference and the unit pixel size as the first actual distance;

[0017] taking a difference between half of the number of pixel matrixes of the projection image and the second pixel value as a second difference, and taking a product of the second difference and the unit pixel size as the second actual distance.

[0018] Optionally, determining the first X distance and the first Y distance based on the first actual distance, the second actual distance, the detector distance, and the turntable distance includes:

[0019] Based on formula Calculate the first X distance, and based on the formula Calculate the first Y distance;

[0020] in, Let X be the first X distance, b be the first Y distance, A be the first actual distance, SOD be the turntable distance, SDD be the detector distance, and B be the second actual distance.

[0021] Optionally, determining the second X distance and the second Y distance moved before each rotation in multiple subsequent rotations based on the first X distance, the first Y distance, and a preset number of rotations includes:

[0022] Based on the first X distance and the first Y distance, determine the deflection angle of the region of interest;

[0023] Based on formula Calculate the second X distance, and based on the formula Calculate the second Y distance;

[0024] in, The second X distance corresponds to the i-th rotation. The second Y distance corresponds to the i-th rotation. Let X be the first distance, b be the first distance, i be the i-th subsequent rotation, N be the number of rotations, and α be the deflection angle.

[0025] Optionally, controlling the turntable to perform its first rotation and controlling the machine scanning based on the first X distance and the first Y distance includes:

[0026] The turntable is controlled to move a first X distance in the positive X-axis direction, and the turntable is controlled to move a first Y distance in the negative Y-axis direction;

[0027] The control unit scans and performs the first rotation.

[0028] Optionally, the turntable is controlled to perform each subsequent rotation and the machine tool is controlled to scan based on the second X distance and the second Y distance corresponding to each rotation in multiple subsequent rotations;

[0029] The turntable is controlled to move along the negative X-axis direction by the second X distance corresponding to the current rotation, and the turntable is controlled to move along the negative Y-axis direction by the second Y distance corresponding to the current rotation.

[0030] Control the machine to scan and execute the current rotation.

[0031] Optionally, determining the X-axis coordinate pixel value of the region of interest in the first projected image to obtain the first pixel value includes:

[0032] Based on the image recognition algorithm, the region of interest in the first projected image is determined, and the X-axis coordinate pixel value of the center point of the region of interest is used to obtain the first pixel value.

[0033] Secondly, this application provides a control terminal, including a processor and a memory, wherein the memory stores machine-readable instructions executable by the processor, and when the control terminal is running, the processor executes the machine-readable instructions to perform the steps of the industrial computed tomography method described in the first aspect.

[0034] Thirdly, this application provides a scanning system, which includes: a control terminal, an X-ray source, a turntable, and a detector as described in the second aspect, wherein the turntable is used to place the sample to be tested;

[0035] The control terminal is connected to the X-ray source, the turntable, and the detector, respectively, and performs the steps of the industrial computed tomography method as described in the first aspect.

[0036] Fourthly, this application provides a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps of the industrial computed tomography method described above.

[0037] The beneficial effects of this application are as follows: First and second projected images of the sample under test are acquired from the detector when the turntable is at a first rotation angle and a second rotation angle, respectively. The pixel values ​​of the X-axis coordinates of the regions of interest in the first and second projected images are determined, resulting in first and second pixel values. Based on the first and second pixel values, the number of columns in the pixel matrix of the projected image, the detector distance, the turntable distance, and the unit pixel size, the first X-distance and first Y-distance of movement before the first rotation are determined. Based on the first X-distance, the first Y-distance, and the number of rotations, the second X-distance and second Y-distance of movement before each subsequent rotation are determined. The turntable is controlled to perform the first rotation and the machine scan is controlled based on the first X-distance and the first Y-distance. Furthermore, the turntable is controlled to perform each subsequent rotation and the machine scan is controlled based on the second X-distance and second Y-distance corresponding to each subsequent rotation. This application determines the first pixel value and the second pixel value of the region of interest under the first and second rotation angles in advance, thereby determining the movement distance corresponding to the first rotation and the movement distance corresponding to subsequent rotations. Before the first and subsequent rotations, the turntable is moved according to the corresponding movement distance so that the region of interest of the sample under test is located at the center of rotation. The control process is simple, the scan preparation time is optimized, the difficulty of scanning operation for staff is reduced, and the scanning effect is improved. Attached Figure Description

[0038] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of the structure of a scanning system provided in an embodiment of this application;

[0040] Figure 2 This is a schematic diagram of another scanning system provided in an embodiment of this application;

[0041] Figure 3 This is a schematic flowchart of an industrial computed tomography (CT) method provided in an embodiment of this application;

[0042] Figure 4 This is a schematic diagram of a subsequent rotation provided in an embodiment of this application;

[0043] Figure 5 This is a schematic diagram of the structure of a control terminal provided in an embodiment of this application;

[0044] Figure 6This is a schematic diagram of a test sample provided in an embodiment of this application;

[0045] Figure 7 This is a comparative schematic diagram of a method provided in an embodiment of this application. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the accompanying drawings in this application are for illustrative and descriptive purposes only and are not intended to limit the scope of protection of this application. Furthermore, it should be understood that the schematic drawings are not drawn to scale. The flowcharts used in this application illustrate operations implemented according to some embodiments of this application. It should be understood that the operations in the flowcharts may not be implemented in sequence, and steps without logical contextual relationships may be reversed or implemented simultaneously. In addition, those skilled in the art, guided by the content of this application, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts.

[0047] Furthermore, the described embodiments are merely some, not all, of the embodiments of this application. The components of the embodiments of this application described and illustrated herein can typically be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0048] It should be noted that the term "comprising" will be used in the embodiments of this application to indicate the presence of the features declared thereafter, but does not exclude the addition of other features.

[0049] In existing technologies, when industrial CT equipment uses fine conical beam scanning to inspect samples, the equipment is typically manually adjusted by operators to ensure that the region of interest remains at the center of rotation during the inspection process. However, this manual adjustment method is inefficient, time-consuming, and requires high precision in the operator's eyesight and stability of their technique, leading to a significant increase in error rates and ultimately increasing inspection costs.

[0050] Based on this, this application proposes an industrial computed tomography (CT) method. This method acquires the X-axis coordinates of the region of interest (ROI) of the turntable at a first rotation angle and at a second rotation angle, obtaining first and second pixel values. Then, based on the first and second pixel values, it determines the first X-distance, first Y-distance, second X-distance, and second Y-distance of movement before the initial rotation. The turntable is controlled to perform the initial rotation and the machine scan based on the first X-distance and first Y-distance. Furthermore, the turntable is controlled to perform subsequent rotations and the machine scan based on the second X-distance and second Y-distance corresponding to each subsequent rotation. Therefore, this application optimizes the scanning effect and improves scanning efficiency by moving the turntable according to the calculated movement distance before rotation, thereby automatically moving the RPI of the sample to the rotation center of the turntable at each scanning angle through a virtual axis function.

[0051] Figure 1 This is a schematic diagram of the structure of a scanning system provided in an embodiment of this application. Figure 1 As shown, the scanning system includes a control terminal, an X-ray source, a turntable, and a detector. The turntable is used to place the sample to be tested. The control terminal is connected to the X-ray source, the turntable, and the detector, and executes the steps of the industrial computed tomography (CT) method.

[0052] Figure 2 This is a schematic diagram of another scanning system provided in an embodiment of this application. For example... Figure 2 As shown, the X-ray source emits probe rays that penetrate the sample under test. The turntable carries the sample and can move and rotate under the control of the control terminal. The detector receives the rays after they pass through the sample and converts them into a projection image based on the difference in ray intensity. Before the test, the rays passing through the center point of the turntable are projected onto the detection center of the detector plane.

[0053] Next, refer to Figure 3 This paper provides a detailed introduction to the process of industrial computed tomography (CT) scanning. Specifically, Figure 3 This is a schematic flowchart of an industrial computed tomography (CT) method provided in an embodiment of this application.

[0054] S301. Acquire the first projection image of the sample under test sent by the detector when the turntable is at the first rotation angle, and determine the X-axis coordinate pixel value of the region of interest in the first projection image to obtain the first pixel value. Acquire the second projection image of the sample under test sent by the detector when the turntable is at the second rotation angle, and determine the X-axis coordinate pixel value of the region of interest in the second projection image to obtain the second pixel value.

[0055] The first rotation angle can be the initial angle of the turntable before the test begins, such as 0 degrees. The second rotation angle can be a 90-degree counterclockwise rotation.

[0056] Optionally, the region of interest (ROI) can be the sample under test in the projection image generated by the detector, or a region of interest within the sample. For example, if a nut is scanned, the entire nut can be considered the ROI in the projection image generated by the detector, or a specific protrusion on the nut can be considered the ROI. The ROI can be selected and determined by the operator in the image according to actual needs.

[0057] Optionally, the X-axis pixel value of the region of interest can be the X-axis pixel value of the center point of the region of interest. In the projected image, the origin of the coordinate axis can be the point located at the lower left corner of the image.

[0058] S302. Based on the first pixel value, the second pixel value, the preset number of columns in the projection image pixel matrix, the detector distance from the ray source to the detector, the turntable distance from the ray source to the turntable, and the unit pixel size, determine the first X distance and the first Y distance moved before the first rotation.

[0059] As an optional implementation, the actual horizontal and vertical distances between the region of interest (ROI) and the center point of the projected image can be determined first based on the first pixel value, the second pixel value, and the unit pixel size. It should be understood that pixel values ​​are pixel coordinates and need to be converted based on the unit pixel size to obtain the actual distance to the ROI. Then, the first X-distance and first Y-distance corresponding to the turntable are determined based on the actual horizontal and vertical distances between the ROI and the center point of the projected image, the detector distance, and the turntable distance. The first X-distance is the horizontal distance between the ROI and the rotation center of the turntable, representing the distance the turntable needs to move along the X-axis; the first Y-distance is the vertical distance between the ROI and the rotation center of the turntable, representing the distance the turntable needs to move along the Y-axis.

[0060] It is worth noting that the rotation center of the turntable is not necessarily the physical center axis of the turntable. Therefore, before an industrial CT machine is put into use, the turntable needs to be adjusted so that the rotation center of the turntable is aligned with the focal point of the X-ray source and the center of the CT detector.

[0061] Among them, the detector distance from the X-ray source to the detector is the distance between the X-ray source and the imaging plane where the detector is located, and the turntable distance from the X-ray source to the turntable is the distance from the X-ray source to the rotation center of the turntable.

[0062] The number of columns in the pixel matrix of the projected image and the size of the unit pixel are both related to the resolution of the projected image, and this embodiment does not impose any restrictions on them.

[0063] S303. Based on the first X distance, the first Y distance, and the preset number of rotations, determine the second X distance and the second Y distance that are moved before each rotation in multiple subsequent rotations.

[0064] The number of rotations equals the number of scans, determined according to scanning requirements. Subsequent rotations refer to all rotations after the initial rotation. Each subsequent rotation corresponds to a second X distance and a second Y distance. The second X distance and second Y distance for each subsequent rotation can be different.

[0065] The second X distance is the horizontal distance between the region of interest and the rotation center of the turntable, which is the distance the turntable needs to move in the X-axis direction. The second Y distance is the vertical distance between the region of interest and the rotation center of the turntable, which is the distance the turntable needs to move in the Y-axis direction.

[0066] It is worth noting that before each subsequent rotation, the turntable position can be restored to its initial position, that is, to the position before the first rotation.

[0067] S304. Control the turntable to perform the first rotation and control the machine to scan based on the first X distance and the first Y distance, and control the turntable to perform each subsequent rotation and control the machine to scan based on the second X distance and the second Y distance corresponding to each rotation in multiple subsequent rotations.

[0068] Specifically, before the first rotation, the control terminal controls the turntable to move along the X-axis by a first X distance and along the Y-axis by a first Y distance. After the movement is completed, the control terminal controls the detector to perform a scan. Before each subsequent rotation, the control terminal controls the turntable to move along the X-axis by a second X distance and along the Y-axis by a second Y distance. After the movement is completed, the control terminal controls the turntable to rotate and perform a scan until the preset number of scans is reached.

[0069] In this embodiment, the first and second projected images of the sample under test sent by the detector when the turntable is at the first and second rotation angles are acquired, and the X-axis coordinate pixel values ​​of the region of interest in the first and second projected images are determined to obtain the first and second pixel values. Based on the first and second pixel values, the number of columns in the pixel matrix of the projected image, the detector distance, the turntable distance, and the unit pixel size, the first X distance and the first Y distance moved before the first rotation are determined. Based on the first X distance, the first Y distance, and the number of rotations, the second X distance and the second Y distance moved before each rotation in multiple subsequent rotations are determined. Based on the first X distance and the first Y distance, the turntable is controlled to perform the first rotation and the machine is controlled to scan. Based on the second X distance and the second Y distance corresponding to each rotation in multiple subsequent rotations, the turntable is controlled to perform each subsequent rotation and the machine is controlled to scan. This embodiment determines the first pixel value and the second pixel value of the region of interest under the first and second rotation angles in advance, thereby determining the movement distance corresponding to the first rotation and the movement distance corresponding to subsequent rotations. Before the first and subsequent rotations, the turntable is moved according to the corresponding movement distance so that the region of interest of the sample under test is located at the center of rotation. The control process is simple, the scan preparation time is optimized, the difficulty of scanning operation for staff is reduced, and the scanning effect is improved.

[0070] Next, the process of determining the first X distance and the first Y distance before the first rotation in step S302 above will be described.

[0071] Optionally, a first actual distance and a second actual distance are determined based on the first pixel value, the second pixel value, the number of columns in the pixel matrix of the projected image, and the unit pixel size. The first actual distance is the horizontal distance between the region of interest on the plane where the detector is located and the detection center when the turntable is at the first rotation angle, and the second actual distance is the vertical distance between the region of interest on the plane where the detector is located and the detection center when the turntable is at the second rotation angle.

[0072] Since the rotation center of the turntable corresponds to the detection center in the scanning scene, it is necessary to convert the first pixel value and the second pixel value into a distance relationship with the detection center. Specifically, the center column where the center point of the projected image is located can be determined based on the number of columns in the pixel matrix of the projected image. Then, based on this center column, the actual distance between the corresponding regions of interest in the first and second projected images and the center column is determined, namely the first actual distance and the second actual distance.

[0073] Optionally, the first X distance and the first Y distance are determined based on the first actual distance, the second actual distance, the detector distance, and the turntable distance.

[0074] As an optional implementation, the first X distance and the first Y distance can be determined based on the following formulas (1) and (2):

[0075] (1)

[0076] (2)

[0077] Where a is the first X distance, b is the first Y distance, A is the first actual distance, B is the second actual distance, SOD is the turntable distance, and SDD is the detector distance. This represents the magnification ratio along the X-axis. This represents the magnification ratio along the Y-axis.

[0078] In this embodiment, a first actual distance and a second actual distance are determined based on the first pixel value, the second pixel value, the number of columns in the pixel matrix of the projected image, and the unit pixel size. The first actual distance is the distance between the region of interest on the plane where the detector is located and the Y-axis of the detector when the turntable is at the first rotation angle. The second actual distance is the distance between the region of interest on the plane where the detector is located and the Y-axis of the detector when the turntable is at the second rotation angle. Based on the first actual distance, the second actual distance, the detector distance, and the turntable distance, a first X distance and a first Y distance are determined. Thus, the deviation between the region of interest and the rotation center of the turntable is calculated based on the projected image, so that the turntable is moved according to the deviation so that the region of interest is located at the rotation center of the turntable.

[0079] The following section describes the process of determining the first and second actual distances based on the first pixel value, the second pixel value, the number of columns in the projected image pixel matrix, and the unit pixel size.

[0080] Optionally, the difference between the first pixel value and half the number of columns in the pixel matrix of the projected image is taken as the first difference, and the product of the first difference and the unit pixel size is taken as the first actual distance.

[0081] The first actual distance can be calculated based on the following formula (3):

[0082] (3)

[0083] Where m is the first pixel value, L is the number of columns in the pixel matrix of the projected image, and E is the unit pixel size.

[0084] Optionally, the difference between half the number of columns of the projected image pixel matrix and the second pixel value is taken as the second difference, and the product of the second difference and the unit pixel size is taken as the second actual distance.

[0085] The second actual distance can be calculated based on the following formula (4):

[0086] (4)

[0087] Where n is the second pixel value, L is the number of columns in the pixel matrix of the projected image, and E is the unit pixel size.

[0088] In this embodiment, the first actual distance and the second actual distance are accurately calculated based on the first pixel value, the second pixel value, the number of columns in the pixel matrix of the projected image, and the unit pixel size.

[0089] As an optional implementation, the process of determining the first X distance and the first Y distance in the above steps is as follows:

[0090] Optionally, the first X distance is calculated based on formula (5), and the first Y distance is calculated based on formula (6):

[0091] (5)

[0092] (6)

[0093] in, Let X be the first X distance, b be the first Y distance, A be the first actual distance, SOD be the turntable distance, SDD be the detector distance, and B be the second actual distance.

[0094] Formulas (5) and (6) can be determined based on formulas (1) and (2).

[0095] Next, the process of determining the second X distance and the second Y distance moved before each rotation in multiple subsequent rotations in step S303 above will be introduced.

[0096] Optionally, the deflection angle of the region of interest can be determined based on the first X distance and the first Y distance.

[0097] The deflection angle of the region of interest is the angle between the line connecting the region of interest and the rotation center of the turntable and the Y-axis of the turntable.

[0098] Specifically, the sine and cosine values ​​of the deflection angle of the region of interest can be calculated and determined based on the following formulas (7) and (8):

[0099] (7)

[0100] (8)

[0101] Where α is the deflection angle of the region of interest.

[0102] Then, based on the inverse trigonometric function, the deflection angle of the region of interest is calculated and determined according to sinα and cosα.

[0103] Optionally, the second X distance is calculated based on the following formula (9), and the second Y distance is calculated based on the following formula (10):

[0104] (9)

[0105] (10)

[0106] Formula (9) can be obtained from the following formula (11):

[0107] (11)

[0108] Formula (10) can be obtained from the following formula (12):

[0109] (12)

[0110] in, The second X distance corresponds to the i-th rotation. The second Y distance corresponding to the i-th rotation. Let x be the first X distance, b be the first Y distance, i be the i-th subsequent rotation, N be the number of rotations, and α be the deflection angle.

[0111] It is worth mentioning that instead of calculating the offset angle according to formulas (7) and (8), the sine and cosine values ​​of the offset angle can be directly substituted into formulas (9) and (10) above to calculate the second X distance and the second Y distance.

[0112] In this embodiment, by calculating the second X distance and the second Y distance, the distance that the turntable needs to move before each subsequent rotation is accurately calculated, so that the region of interest is located at the rotation center of the turntable.

[0113] As an optional implementation, the process of controlling the turntable to perform the first rotation and controlling the machine scanning based on the first X distance and the first Y distance in step S304 above is as follows:

[0114] Optionally, the turntable is controlled to move a first X distance in the positive X-axis direction and a first Y distance in the negative Y-axis direction.

[0115] Specifically, the turntable's Y-axis is controlled to move a first X distance along the positive X-axis direction, and the turntable's X-axis is controlled to move a first Y distance along the negative Y-axis direction.

[0116] Optionally, the control unit scans and performs the first rotation.

[0117] Optionally, after the movement, the detector is controlled to generate the first scan image. After the scan is completed, the turntable can be controlled to return to the initial position and perform the first rotation.

[0118] The region of interest is located in the center of the first scanned image, resulting in high scan clarity.

[0119] As an optional implementation, the process of controlling the turntable to perform each subsequent rotation and controlling the machine to scan in step S304 above, based on the second X distance and the second Y distance corresponding to each rotation in multiple subsequent rotations, is as follows: control the turntable to move the second X distance corresponding to the current rotation in the negative X-axis direction, and control the turntable to move the second Y distance corresponding to the current rotation in the negative Y-axis direction.

[0120] Specifically, the turntable's Y-axis is controlled to move a second X distance along the positive X-axis direction, and the turntable's X-axis is controlled to move a second Y distance along the negative Y-axis direction.

[0121] The current rotation is one of the subsequent rotations.

[0122] Optionally, the control unit scans and executes the current rotation.

[0123] Optionally, after each scan by the control unit, the turntable can be controlled to return to its initial position before proceeding with the next subsequent movement and rotation.

[0124] In this embodiment, the control unit performs scanning to obtain the scanning images corresponding to subsequent rotations, and the region of interest in each scanning image is located at the center of the scanning image.

[0125] It is worth noting that since the turntable center was adjusted to the rotation center before the machine was put into use, the rotation center at the zero point of the turntable during the first rotation angle was taken as the rotation origin. The current movement coordinates of the turntable's rotation center were determined based on the first X distance, the first Y distance, the second X distance, and the second Y distance. For example, the current movement coordinates corresponding to the first rotation were (a, -b), and the current movement coordinates corresponding to subsequent rotations were (-b, -b). , - During each rotation control, it is only necessary to move the rotation center of the turntable to the current movement coordinate to scan a clear image, without having to restore the turntable position to the initial position.

[0126] Figure 4 This is a schematic diagram of a subsequent rotation provided in an embodiment of this application. For example... Figure 4 As shown, the turntable can first rotate, and then move based on the current coordinates, so that the region of interest is located at the center of rotation. As an alternative implementation, the turntable can also move first, and then rotate. Figure 4 This is just one example; the specific execution order can be selected according to actual needs.

[0127] As an optional implementation, in step S301 above, the region of interest in the first and second projected images can be determined by the operator.

[0128] As another optional implementation, if the region of interest in the sample being tested is a regular and distinct patterned region, then the implementation steps for determining the X-axis coordinate pixel value of the region of interest in the first projected image and obtaining the first pixel value in step S301 above are as follows:

[0129] Optionally, based on an image recognition algorithm, the region of interest in the first projected image is determined, and the X-axis coordinate pixel value of the center point of the region of interest is used to obtain the first pixel value.

[0130] Specifically, an image recognition algorithm can be determined based on the characteristics of the region of interest (ROI) to identify the ROI in the first projected image. If the ROI has a large difference in grayscale from the background, such as pores or impurities in a metal part, the ROI in the first projected image can be determined using grayscale thresholding or clustering. If the ROI has a fixed shape, such as a standard aperture or a square slot, the ROI in the first projected image can be determined based on template matching or shape feature extraction. If the ROI has clear edges or obvious boundaries, such as scratches on a part or the edge of a groove, the ROI in the first projected image can be determined using edge detection and contour fitting.

[0131] In this embodiment, based on an image recognition algorithm, the region of interest in the first projected image is determined, and the X-axis coordinate pixel value of the center point of the region of interest is used to obtain the first pixel value, thereby efficiently determining the region of interest and the corresponding first pixel value.

[0132] This application embodiment also provides a control terminal, including: a processor and a memory, wherein the memory stores machine-readable instructions executable by the processor, and when the control terminal is running, the processor executes the machine-readable instructions to perform the steps of the above-described industrial computed tomography method.

[0133] This application also provides a control terminal, such as... Figure 5 The diagram shown is a schematic representation of a control terminal provided in an embodiment of this application, including a processor 501, a memory 502, and a bus. The memory 502 stores machine-readable instructions executable by the processor 501. When the control terminal is running, the processor 501 and the memory 502 communicate via the bus. When the machine-readable instructions are executed by the processor 501, the processing of the aforementioned industrial computed tomography (CT) method is performed.

[0134] For example, Figure 6This is a schematic diagram of a test sample provided in an embodiment of this application. This application uses an irregularly shaped plastic as the test sample, and the entire image of the irregularly shaped plastic is taken as the region of interest. The test sample is as follows: Figure 6 As shown. Figure 7 This is a comparative schematic diagram of a method provided in an embodiment of this application, such as... Figure 7 As shown, by scanning the sample using the industrial computed tomography method described in this application, the following results can be obtained: Figure 7 The multiple scan images shown on the left are, respectively, scan image 268, scan image 296, and scan image 411. Figure 7 The scan images shown on the right are multiple scan images obtained by manually adjusting the sample to the position of the rotation center using existing technology. They are the 268th scan image, the 296th scan image, and the 411th scan image. Figure 7 The scanning process using existing techniques and the method described in this application involves the same number of rotations. Figure 7 It is evident that the scanned images obtained using the method in this application and the method using existing technologies are identical for the same number of scans. Therefore, the correct scanned image can be reconstructed using the method in this application.

[0135] This application embodiment also provides a scanning system, which includes: the control terminal, radiation source, turntable and detector described above, wherein the turntable is used to place the sample to be tested;

[0136] The control terminal is connected to the X-ray source, the turntable, and the detector, respectively, and performs the steps of the industrial computed tomography method described above.

[0137] This application also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, performs the steps of the above-described industrial computed tomography method.

[0138] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems and devices described above can be referred to the corresponding processes in the method embodiments, and will not be repeated here. In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of modules is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection can be through some communication interfaces; the indirect coupling or communication connection of devices or modules can be electrical, mechanical, or other forms.

[0139] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. If the functions are implemented as 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 this invention, or the part that contributes to the prior art, or a part of the 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 to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this invention. The aforementioned storage medium includes: USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media capable of storing program code.

[0140] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. An industrial computed tomography (CT) method, characterized in that, The method is applied to the control terminal of a scanning system, the scanning system comprising: the control terminal, an X-ray source, a turntable, and a detector, the turntable being used to place the sample to be tested, and the method comprising: A first projection image of the sample under test sent by the detector when the turntable is at a first rotation angle is acquired, and the X-axis coordinate pixel value of the region of interest in the first projection image is determined to obtain a first pixel value; a second projection image of the sample under test sent by the detector when the turntable is at a second rotation angle is acquired, and the X-axis coordinate pixel value of the region of interest in the second projection image is determined to obtain a second pixel value; Based on the first pixel value, the second pixel value, the preset number of columns in the projected image pixel matrix, the detector distance from the ray source to the detector, the turntable distance from the ray source to the turntable, and the unit pixel size, determine the first X distance and the first Y distance to move before the first rotation; Based on the first X distance, the first Y distance, and the preset number of rotations, determine the second X distance and the second Y distance to move before each rotation in multiple subsequent rotations; The turntable is controlled to perform the first rotation and the machine scan based on the first X distance and the first Y distance, and the turntable is controlled to perform each subsequent rotation and the machine scan based on the second X distance and the second Y distance corresponding to each rotation in multiple subsequent rotations.

2. The industrial computed tomography method according to claim 1, characterized in that, The step of determining the first X distance and the first Y distance to move before the first rotation based on the first pixel value, the second pixel value, the preset number of columns in the projected image pixel matrix, the detector distance from the ray source to the detector, the turntable distance from the ray source to the turntable, and the unit pixel size includes: Based on the first pixel value, the second pixel value, the number of columns in the pixel matrix of the projected image, and the unit pixel size, a first actual distance and a second actual distance are determined. The first actual distance is the horizontal distance between the region of interest on the plane where the detector is located when the turntable is at a first rotation angle and the detection center. The second actual distance is the vertical distance between the region of interest on the plane where the detector is located when the turntable is at a second rotation angle. The first X distance and the first Y distance are determined based on the first actual distance, the second actual distance, the detector distance, and the turntable distance.

3. The industrial computed tomography method according to claim 2, characterized in that, The step of determining the first actual distance and the second actual distance based on the first pixel value, the second pixel value, the number of columns in the projected image pixel matrix, and the unit pixel size includes: The difference between the first pixel value and half the number of columns in the pixel matrix of the projected image is taken as the first difference, and the product of the first difference and the unit pixel size is taken as the first actual distance. The difference between half the number of columns in the projected image pixel matrix and the second pixel value is taken as the second difference, and the product of the second difference and the unit pixel size is taken as the second actual distance.

4. The industrial computed tomography method according to claim 2, characterized in that, Determining the first X distance and the first Y distance based on the first actual distance, the second actual distance, the detector distance, and the turntable distance includes: Based on formula Calculate the first X distance, and based on the formula Calculate the first Y distance; in, Let X be the first X distance, b be the first Y distance, A be the first actual distance, SOD be the turntable distance, SDD be the detector distance, and B be the second actual distance.

5. The industrial computed tomography method according to claim 1, characterized in that, The step of determining the second X distance and the second Y distance before each rotation in multiple subsequent rotations based on the first X distance, the first Y distance, and a preset number of rotations includes: Based on the first X distance and the first Y distance, determine the deflection angle of the region of interest; Based on formula Calculate the second X distance, and based on the formula Calculate the second Y distance; in, The second X distance corresponds to the i-th rotation. The second Y distance corresponds to the i-th rotation. Let X be the first distance, b be the first distance, i be the i-th subsequent rotation, N be the number of rotations, and α be the deflection angle.

6. The industrial computed tomography method according to claim 1, characterized in that, The step of controlling the turntable to perform its first rotation and controlling the machine scanning based on the first X distance and the first Y distance includes: The turntable is controlled to move a first X distance in the positive X-axis direction, and the turntable is controlled to move a first Y distance in the negative Y-axis direction; The control unit scans and performs the first rotation.

7. The industrial computed tomography method according to claim 1, characterized in that, Based on the second X distance and the second Y distance corresponding to each subsequent rotation, the turntable is controlled to perform each subsequent rotation and the machine tool is controlled to scan. The turntable is controlled to move along the negative X-axis direction by the second X distance corresponding to the current rotation, and the turntable is controlled to move along the negative Y-axis direction by the second Y distance corresponding to the current rotation. Control the machine to scan and execute the current rotation.

8. The industrial computed tomography method according to claim 1, characterized in that, Determining the X-axis coordinate pixel value of the region of interest in the first projected image to obtain the first pixel value includes: Based on the image recognition algorithm, the region of interest in the first projected image is determined, and the X-axis coordinate pixel value of the center point of the region of interest is used to obtain the first pixel value.

9. A control terminal, characterized in that, include: A processor and a memory, the memory storing machine-readable instructions executable by the processor, wherein when the control terminal is running, the processor executes the machine-readable instructions to perform the steps of the industrial computed tomography method as described in any one of claims 1 to 8.

10. A scanning system, characterized in that, The scanning system includes: a control terminal, an X-ray source, a turntable, and a detector as described in claim 9, wherein the turntable is used to place the sample to be tested; The control terminal is connected to the X-ray source, the turntable, and the detector, respectively, and performs the steps of the industrial computed tomography method as described in any one of claims 1-8.

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