Automatic auxiliary alignment system and method for X-ray nondestructive testing

Abstract

The invention relates to an automatic auxiliary alignment system and method for X-ray nondestructive testing, and belongs to the technical field of measurement. The device comprises an X-ray source (1), an auxiliary positioning laser lamp (2), a visible light camera (3), an auxiliary positioning mark sticker (4), a power supply module (5), an objective table (6) and a flat panel detector (7). According to the method, automatic control and a computer image processing technology are combined, I-shaped graphic information is rich, the offset of multiple axes can be calculated, the complexity of an auxiliary tool is simplified in automatic auxiliary alignment, and the method can play an important role in nondestructive testing.

Description

Technical Field

[0001] This invention belongs to the field of measurement technology, specifically relating to an automatic auxiliary alignment system and method for X-ray non-destructive testing. Background Technology

[0002] In the industrial sector, X-ray nondestructive testing (NDT) is widely used for defect detection in circuit boards, battery modules, and mechanical structural components, providing a technical guarantee for product quality. In power module X-ray imaging, the placement of the tested item on the stage varies during each inspection, leading to misalignment between the tested product image and the standard image (X-ray image of a defect-free product). Typically, image registration using features such as SIFT and SURF is employed to address this misalignment and eliminate inaccuracies. However, this method is ineffective for power modules with a certain thickness (server, large equipment power modules). X-ray imaging involves emitting rays from a point source and receiving them through a flat-panel detector. The image captured of the object being tested resembles the projection of a rod-shaped object under the point source. When the rod-shaped object is directly below the light source, the projection is a point; when it moves a short distance, the projection becomes a line segment. Similarly, deviations in the object cause changes in the X-ray image, known as the "point-line effect." This effect varies with the distance between the object and the light source, as well as the object's thickness; the closer the object, the more pronounced the effect, and the thicker the object, the more pronounced the effect. The point-line effect manifests in the image not only as changes in displacement and scaling but also as increases or decreases the object's information, which cannot be easily adjusted through simple image geometric transformations. Therefore, the inaccurate detection of anomalies caused by the "point-line effect" is one of the pressing problems to be solved in X-ray nondestructive testing. This invention arises precisely from this practical need. Summary of the Invention

[0003] (a) Technical problems to be solved

[0004] The technical problem to be solved by the present invention is how to provide an automatic auxiliary alignment system and method for X-ray nondestructive testing to solve the problem of inaccurate abnormal detection caused by the "dot-line effect".

[0005] (II) Technical Solution

[0006] To solve the above-mentioned technical problems, the present invention proposes an automatic auxiliary alignment system for X-ray non-destructive testing, which includes: an X-ray source (1), an auxiliary positioning laser lamp (2), a visible light camera (3), an auxiliary positioning marker (4), a power module (5), a stage (6), and a flat panel detector (7).

[0007] The X-ray source (1) is used to emit X-rays, and the flat panel detector (7) is used to receive X-rays and acquire X-ray images;

[0008] The auxiliary positioning laser lamp (2) emits a red "work" - shaped pattern laser. The auxiliary positioning label (4) is printed with the same "work" - shaped pattern, and the pattern color is blue. The auxiliary positioning label (4) is attached to the surface of the power supply module (5) of the measured object. When the measured object is placed without deviation, the red "work" - shaped pattern laser coincides with the "work" - shaped pattern on the auxiliary positioning label (4).

[0009] The visible - light camera (3) is directed at the auxiliary positioning label (4) on the power supply module (5) of the measured object, and is used to obtain the coincidence situation between the "work" - shaped pattern laser and the "work" - shaped pattern on the auxiliary positioning label (4), providing basic data for deviation calculation.

[0010] The carrier stage (6) is used to carry the power supply module (5) of the measured object and has at least three - degree - of - freedom movement capabilities in the front - rear, left - right, and rotational directions.

[0011] The present invention also provides an X - ray non - destructive testing automatic auxiliary alignment method, which includes: obtaining an auxiliary positioning image I, extracting the "work" - shaped pattern, calculating the offset, determining whether it is less than the minimum offset, and compensating the movement of the carrier stage;

[0012] S1. Obtaining the auxiliary positioning image I is to obtain an RGB color image by taking a picture with the visible - light camera (3);

[0013] S2. The extraction of the "work" - shaped pattern is divided into the extraction of the "work" - shaped pattern on the auxiliary positioning label (4) and the extraction of the "work" - shaped pattern emitted by the auxiliary positioning laser lamp (2);

[0014] S3. The calculation of the offset includes extracting the line segments composed of the "work" - shaped marks, calculating the translational offset, and calculating the rotational offset, forming an offset parameter group (△x, △y, △θ). △x represents the left - right translational offset, △y represents the front - rear translational offset, and △θ represents the rotational offset;

[0015] S4. Whether it is less than the minimum offset is determined according to the actual calculation accuracy of the offset. During the cyclic compensation process, when the calculated offset fluctuates positively and negatively within a certain range and the number of fluctuations exceeds 5 times, the minimum offset is equal to the average value of the offsets calculated 5 times;

[0016] S5. The compensating movement of the carrier stage is to move the carrier stage in the opposite direction according to the calculated offset parameter group (△x, △y, △θ), so that the power supply module (5) of the measured object is in the same position as the standard placement position.

[0017] (III) Beneficial effects

[0018] The present invention provides an X-ray non-destructive testing automatic auxiliary alignment system and method. By combining automatic control and computer image processing technologies, the "I"-shaped pattern has rich information, enabling the calculation of multiple axis offset amounts, simplifying the complexity of auxiliary tools in automatic auxiliary alignment, and playing an important role in non-destructive testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a system composition diagram of the X-ray non-destructive testing automatic auxiliary alignment system and method of the present invention;

[0020] Figure 2 It is a flowchart of the X-ray non-destructive testing automatic alignment method;

[0021] Figure 3 It is a schematic diagram of the "I" mark;

[0022] Figure 4 It is a schematic diagram of the proportional relationship of the △y offset;

[0023] Figure 5 It is a top view projection schematic diagram of the laser lamp and the power supply module. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] To make the objectives, contents, and advantages of the present invention clearer, the following further describes the detailed embodiments of the present invention in conjunction with the drawings and embodiments.

[0025] The present invention discloses an X-ray non-destructive testing automatic auxiliary alignment system and method, which mainly includes an X-ray source, an auxiliary positioning laser lamp, a visible light camera, an auxiliary positioning label, a power supply module (the object to be measured), a stage, and a flat panel detector. The main idea is to use the auxiliary laser lamp to irradiate an "I"-shaped pattern on the object to be measured, and calculate the displacement and angular difference of the object to be measured on the stage according to the deviation between the pattern and the auxiliary positioning label. The stage performs compensatory movement according to the difference value to compensate for the errors of multiple manual placements of the object to be measured, that is, to achieve the purpose of automatic alignment for X-ray non-destructive testing of the power supply module.

[0026] The present invention provides an X-ray non-destructive testing automatic auxiliary alignment system, including: an X-ray source (1), an auxiliary positioning laser lamp (2), a visible light camera (3), an auxiliary positioning label (4), a power supply module (5), a stage (6), and a flat panel detector (7), as Figure 1 shown. The main idea is to use the auxiliary positioning laser lamp (2) to irradiate an "I"-shaped pattern on the object to be measured, and calculate the displacement and angular difference of the object to be measured on the stage (6) according to the deviation between the pattern and the auxiliary positioning label (4). The stage (6) performs compensatory movement according to the difference value to compensate for the errors of multiple manual placements of the object to be measured, that is, to achieve the purpose of automatic alignment for X-ray non-destructive testing of the power supply module (5).

[0027] In an X-ray non-destructive testing automatic auxiliary alignment system and method, the X-ray source (1) is used to emit X-rays, and the flat panel detector (7) is used to receive X-rays and obtain X-ray images;

[0028] The auxiliary positioning laser lamp (2) emits a red "work" - shaped pattern laser. The auxiliary positioning label (4) is printed with the same "work" - shaped pattern, and the pattern color is blue, and it is attached to the surface of the power supply module (5) of the tested object. When the tested object is placed without deviation (standard), the red "work" - shaped pattern laser coincides with the "work" - shaped pattern on the auxiliary positioning label (4);

[0029] The visible light camera (3) is directed at the auxiliary positioning label (4) on the power supply module (5) of the tested object, and is used to obtain the coincidence situation of the "work" - shaped pattern laser and the "work" - shaped pattern on the auxiliary positioning label (4), providing basic data for deviation calculation;

[0030] The stage (6) is used to carry the power supply module (5) of the tested object, and has at least three degrees of freedom of movement: forward and backward, left and right, and rotation.

[0031] Among them, the process of the X-ray non-destructive testing automatic alignment method is as Figure 2 shown, including: five key steps: obtaining the auxiliary positioning image I, "work" - shaped pattern extraction, calculating the offset, whether it is less than the minimum offset, and compensating movement of the stage.

[0032] S1. Obtaining the auxiliary positioning image I is to obtain an RGB color image by taking a picture with the visible light camera (3).

[0033] S2. The extraction of the "work" - shaped pattern is divided into the extraction of the "work" - shaped pattern on the auxiliary positioning label (4) and the extraction of the "work" - shaped pattern emitted by the auxiliary positioning laser lamp (2). Further,

[0034] The extraction of the "work" - shaped pattern on the auxiliary positioning label (4) includes: first, decomposing the auxiliary positioning image I into three component images I R 、I G 、I B through RGB three-channel decomposition, and then using the pre-set "work" - shaped template image I M to perform template matching operation on I B , finding the area of the "work" - shaped mark in I B , and obtaining the "work" - shaped mark area image I BR corresponding to the auxiliary positioning label (4).

[0035] Similarly, by performing the same calculation on the I R image, the "work" - shaped mark area image corresponding to the auxiliary positioning laser lamp (2) can be obtainedRR .

[0036] S3. The calculated offset includes the extraction of the line segments composed of the "worker" logo, the calculation of the translation offset, and the calculation of the rotation offset, constituting an offset parameter group (△x, △y, △θ). △x represents the left-right translation offset, △y represents the front-back translation offset, and △θ represents the rotation offset.

[0037] S31. Further, the extraction of the line segments composed of the "worker" logo is as Figure 3 shown. First, perform binarization on the regional image I BR and the regional image I RR respectively. During the binarization process, use the otsu method to automatically determine the threshold to obtain the binary images I BRB and I RRB . Then, calculate the equations of the line segments composed of the "worker" through the fast Hough transform. The equation of the line segments of the binary image I RRB is:

[0038] The top horizontal line segment is LR1: y R1 = k R1 x R1 + b R1 , x ∈ [a R1 , c R1 .

[0039] The middle vertical line segment is LR2: y R2 = k R2 x R2 + b R2 , x ∈ [a R2 , c R2 .

[0040] The bottom horizontal line segment is LR3: y R3 = k R3 x R3 + b R3 , x ∈ [a R3 , c R3

[0041] According to the line segment equations, the intersections of L R2 with L R1 and L R3 can be calculated, which are A R1 (X R1 , Y R1 ) and A R2 (X R2 , Y R2 ).

[0042] Similarly, calculate the equations of the line segments composed of the "worker" through the fast Hough transform for the binary image I​BRB The line segments form the equation:

[0043] The top horizontal line segment is LB1: y B1 =k B1 x B1 +b B1 , x∈[a B1 c B1 ]、

[0044] The middle vertical line segment is LB2: y B2 =k B2 x B2 +b B2 , x∈[a B2 c B2 ]、

[0045] The bottom horizontal line segment is LB3:y B3 =k B3 x B3 +b B3 , x∈[a B3 c B3 ].

[0046] L can be calculated from the system of equations for line segments. B2 respectively with L B1 L B3 The intersection points are A and B, respectively. B1 (X) B1 ,Y B1 ) and A B2 (X) B2 ,Y B2 ).

[0047] S32. Furthermore, the calculation of the △x translation offset is based on L. R2 With L B2 The positional relationships and scaling are calculated. The left and right translation offset Δx is calculated based on line segment L. R2 With L B2 The left and right position difference was calculated. Since the measured item was placed on the surface of the platform, the L in the "I" shaped pattern on the auxiliary positioning mark (4) and the "I" shaped pattern emitted by the auxiliary positioning laser light (2) were different. R2 With L B2 All line segments are perpendicular, therefore L R2 The left and right (horizontal) positions can be represented by point A on its line segment. R1 Or A R2 The horizontal coordinate is used to represent its position, and similarly, L... B2 The left and right (horizontal) positions can be represented by point A on its line segment. B1 Or A B2 The x-coordinate is used to represent its position, i.e., △x = |X B1-X R1 |。

[0048] S33. Further, the calculation of the △y translation offset is obtained based on the scaling of line segment L B2 . First, the length l1 of line segment L B1 can be calculated based on A B2 . The length of the "|" line segment in the "I" - shaped pattern on the auxiliary positioning marker sticker (4) can be obtained by actual measurement as l2. As B2 shown, let the distance from the auxiliary positioning laser lamp (2) to the surface of the standard - placed measured object (power supply module (5)) be l0, then it satisfies: Figure 4 , so the △y translation offset: . .

[0049] S34. Further, the calculation of the △θ rotation offset is obtained based on the included - angle relationship between line segment L R1 and L B1 . First, the length l3 of line segment L R1 can be calculated based on A R2 . Secondly, according to the trigonometric - function relationship, as R2 shown, the divergence angle of the auxiliary positioning laser lamp (2) is θ0. Let l4 be the distance in space between the end of the upper "-" on the "I" - shaped pattern of the laser lamp when the power supply module (5) is in the standard placement and the offset placement. Then it satisfies: Figure 5 , , , , . Then, by联立上述四个方程, the rotation offset can be obtained: . Δs is the difference in the vertical direction between the upper edge of the laser lamp shining on the offset - placed measured object (power supply module) and the standard placement.

[0050] S4. Whether it is less than the minimum offset is determined according to the accuracy of the actually calculated offset. Generally, according to experience, when during the cyclic compensation process, the calculated offset fluctuates positively and negatively within a certain range, and the number of fluctuations exceeds 5 times, then the minimum offset is equal to the average value of the offsets calculated 5 times.

[0051] S5. The compensating movement of the stage is to move the stage in the opposite direction according to the calculated offset parameter group (△x, △y, △θ), so that the measured object, the power supply module (5), is consistent with the standard placement position.

[0052] Example 1:

[0053] The following describes the specific implementation manners of the present invention, but is not a limitation on the specific implementation methods.

[0054] An X-ray non-destructive testing automatic auxiliary alignment system and method of the present invention mainly include an X-ray source (1), an auxiliary positioning laser lamp (2), a visible light camera (3), an auxiliary positioning label (4), a power supply module (5), a stage (6), and a flat panel detector (7), as Figure 1 shown. The main idea is to use the auxiliary laser lamp 2 to irradiate a "worker" shaped pattern on the object to be measured, and calculate the displacement and angular difference of the object to be measured (power supply module) on the stage according to the deviation between the pattern and the auxiliary positioning label 5. The stage (6) performs compensatory movement according to the difference value to compensate for the errors of multiple manual placements of the object to be measured, that is, to achieve the purpose of automatic alignment for X-ray non-destructive testing of the power supply module.

[0055] Further, the X-ray source (1) is used to emit X-rays, and the flat panel detector (7) is used to receive X-rays and obtain X-ray images; the auxiliary positioning laser lamp (2) emits a red "worker" shaped pattern laser, and the auxiliary positioning label (4) is printed with the same "worker" shaped pattern, the pattern color is blue, and it is attached to the surface of the power supply module (5) of the object to be measured. When the object to be measured is placed without deviation, the red "worker" shaped pattern laser coincides with the "worker" shaped pattern on the auxiliary positioning label (4); the visible light camera (3) is directly facing the auxiliary positioning label (4) on the power supply module (5) of the object to be measured, and is used to obtain the coincidence situation between the "worker" shaped pattern laser and the "worker" shaped pattern on the auxiliary positioning label (4), providing basic data for deviation calculation. The stage (6) has at least three degrees of freedom of movement in the front and back, left and right, and rotation (360 degrees).

[0056] Among them, the process flow of the X-ray non-destructive testing automatic alignment method is as Figure 2 shown, and it is characterized by including five key steps: obtaining the auxiliary positioning image I, extracting the "worker" shaped pattern, calculating the offset, whether it is less than the minimum offset, and compensatory movement of the stage.

[0057] (1) Obtaining the auxiliary positioning image I is to obtain an RGB color image by taking a picture with the visible light camera (3).

[0058] (2) The extraction of the "worker" shaped pattern is divided into the extraction of the "worker" shaped pattern on the auxiliary positioning label (4) and the extraction of the "worker" shaped pattern emitted by the auxiliary positioning laser lamp (2). Further, the extraction of the "worker" shaped pattern on the auxiliary positioning label (4) is characterized in that first, the auxiliary positioning image I is decomposed into three component images I R 、I G 、I B by decomposing the RGB three channels of the auxiliary positioning image I, and then the pre-set "worker" shaped template image I M is used to perform template matching operation in I B to find I BThe area of the "I"-shaped logo is obtained to get the image I of the "I"-shaped logo area corresponding to the auxiliary positioning logo sticker (4). BR . Similarly, for I R image, the same calculation is performed to obtain the image I of the "I"-shaped logo area corresponding to the auxiliary positioning laser lamp (2). RR .

[0059] The calculation of the offset described in (3) includes the extraction of the line segments forming the "I"-shaped logo, the calculation of the translation offset, and the calculation of the rotation offset, constituting the offset parameter group (△x, △y, △θ). △x represents the left-right translation offset, △y represents the front-back translation offset, and △θ represents the rotation offset.

[0060] (31) Further, the extraction of the line segments forming the "I"-shaped logo is as Figure 3 shown. First, the region images I BR and the region image I RR are respectively subjected to binarization operation. During the binarization process, the otsu method is used to automatically determine the threshold to obtain the binary images I BRB and I RRB . Then, the equations of the line segments forming the "I" are calculated through the fast Hough transform. The line segment composition equations of the binary image I RRB are as follows

[0061] LR1: y R1 =k R1 x R1 +b R1 , x ∈ [a R1 , c R1

[0062] LR2: y R2 =k R2 x R2 +b R2 , x ∈ [a R2 , c R2

[0063] LR3: y R3 =k R3 x R3 +b R3 , x ∈ [a R3 , c R3

[0064] And according to the line segment equation system, the intersections of L R2 with L R1 and L R3 can be calculated respectively, which are A R1 (X R1 , Y R1 ) and A R2 (X R2,Y R2 ).

[0065] Similarly, the equation of the line segments forming the "工" shape is calculated through the fast Hough transform, and the binary image I BRB has the following line segment composition equations:

[0066] LB1: y B1 = k B1 x B1 + b B1 , x ∈ [a B1 , c B1

[0067] LB2: y B2 = k B2 x B2 + b B2 , x ∈ [a B2 , c B2

[0068] LB3: y B3 = k B3 x B3 + b B3 , x ∈ [a B3 , c B3

[0069] And the intersection points of L B2 with L B1 and L B3 can be calculated according to the line segment equations, and the intersection points are A B1 (X B1 , Y B1 ) and A B2 (X B2 , Y B2 ).

[0070] (32) Further, the calculation of the △x translation offset is based on the positional relationship and scaling situation between L R2 and L B2 . The calculation of the left - right translation offset △x is based on the left - right positional difference between the line segments L R2 and L B2 . Since when the measured item is placed on the surface of the stage, the L R2 and L B2 line segments in the "工" - shaped pattern on the auxiliary positioning mark sticker (4) and the "工" - shaped pattern emitted by the auxiliary positioning laser lamp (2) are both in a vertical state, the left - right (horizontal) position of its L R2 can be represented by the abscissa of the point A R1 or A R2 on its line segment. Similarly, for L B2 ​​​The left - right (horizontal) position can be represented by the point A on its line segment B1 or A B2 's abscissa to represent its position, that is, △x = |X B1 - X R1 |.

[0071] (33) Further, the calculation of the △y translation offset is obtained according to the scaling situation of the line segment L B2 . First, according to A B1 , A B2 , the length l1 of the line segment L B2 can be calculated. The length of the "|" line segment in the "work" - shaped pattern on the auxiliary positioning label (4) can be obtained by actual measurement as l2. As Figure 4 shown, let the distance from the auxiliary positioning laser lamp (2) to the surface of the standard - placed measured object (power supply module (5)) be l0, then it satisfies:

[0072]

[0073] Therefore, the △y translation offset:

[0074] .

[0075] (34) Further, the calculation of the △θ rotation offset is obtained according to the included - angle relationship between the line segment L R1 and L B1 . First, according to A R1 , A R2 , the length l3 of the line segment L R2 can be calculated. Secondly, according to the trigonometric function relationship, as Figure 5 shown, the divergence angle of the auxiliary positioning laser lamp (2) is θ0. Let l4 be the distance in space between the end of the "—" on the upper side of the "work" - shaped pattern of the laser lamp when the power supply module (5) is in the standard placement and the cheap placement. Then it satisfies:

[0076] ]]

[0077]

[0078]

[0079]

[0080] Then, by联立上述四个方程,可得旋转偏移量:

[0081] (4) Whether it is less than the minimum offset is determined based on the accuracy of the actual offset calculation. Generally, based on experience, when the offset fluctuates positively or negatively within a certain range for 5 times during the cyclic compensation, the average of the five times is taken as the minimum offset.

[0082] (5) The compensation movement of the platform is to move the platform in the opposite direction according to the offset parameter group (△x, △y, △θ) calculated in step (3) so that the power module (5) of the tested item is consistent with the standard placement position.

[0083] The present invention discloses an automatic auxiliary alignment system and method for X-ray nondestructive testing, which combines automatic control with computer image processing technology. The "I" shaped graphic information is rich and can realize the calculation of multiple axis offsets. It simplifies the complexity of auxiliary tools in automatic auxiliary alignment and plays an important role in nondestructive testing.

[0084] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An automatic auxiliary alignment system for X-ray nondestructive testing, characterized in that, The system includes: an X-ray source (1), an auxiliary positioning laser lamp (2), a visible light camera (3), an auxiliary positioning label (4), a power supply module (5), a stage (6), and a flat panel detector (7); The X-ray source (1) is used to emit X-rays, and the flat panel detector (7) is used to receive X-rays and obtain X-ray images; The auxiliary positioning laser lamp (2) emits a red "worker" - shaped pattern laser. The auxiliary positioning label (4) is printed with the same "worker" - shaped pattern, and the pattern color is blue. The auxiliary positioning label (4) is attached to the surface of the power supply module (5) of the measured object. When the measured object is placed without deviation, the red "worker" - shaped pattern laser coincides with the "worker" - shaped pattern on the auxiliary positioning label (4); The visible light camera (3) is directed at the auxiliary positioning label (4) on the power supply module (5) of the measured object, and is used to obtain the coincidence situation between the "worker" - shaped pattern laser and the "worker" - shaped pattern on the auxiliary positioning label (4), providing basic data for deviation calculation; The stage (6) is used to carry the power supply module (5) of the measured object, and at least has the movement capabilities of three degrees of freedom: front - back, left - right, and rotation.

2. The automatic auxiliary alignment system for X-ray nondestructive testing as described in claim 1, characterized in that, The auxiliary positioning laser lamp (2) is used to irradiate a "worker" - shaped pattern on the measured object, and the displacement and angular difference of the measured object on the stage (6) are calculated according to the deviation between the pattern and the auxiliary positioning label (4). The stage (6) performs compensatory movement according to the difference value, realizing the compensation of the multiple manual placement errors of the measured object, that is, achieving the purpose of automatic alignment for X-ray nondestructive testing of the power supply module (5).

3. An automatic assisted alignment method for X-ray nondestructive testing based on the system described in claim 1 or 2, characterized in that, This method includes: obtaining an auxiliary positioning image I, extracting the "worker" pattern, calculating the offset, determining whether it is less than the minimum offset, and compensatory movement of the stage; S1. Obtaining the auxiliary positioning image I is achieved by taking an RGB color image through the visible light camera (3); S2. The extraction of the "worker" pattern is divided into the extraction of the "worker" pattern on the auxiliary positioning label (4) and the extraction of the "worker" pattern emitted by the auxiliary positioning laser lamp (2); S3. The calculation of the offset includes the extraction of the line segments formed by the "worker" marks, the calculation of the translational offset, and the calculation of the rotational offset, constituting an offset parameter group (△x, △y, △θ). △x represents the left - right translational offset, △y represents the front - back translational offset, and △θ represents the rotational offset; S4. Whether it is less than the minimum offset is determined according to the actual calculation accuracy of the offset. During the cyclic compensation process, when the calculated offset fluctuates positively and negatively within a certain range, and the number of fluctuations exceeds 5 times, the minimum offset is equal to the average value of the offsets calculated 5 times; S5. The compensatory movement of the stage is to move the stage in the opposite direction according to the calculated offset parameter group (△x, △y, △θ), so that the power supply module (5) of the measured item is consistent with the standard placement position.

4. The automatic assisted alignment method for X-ray nondestructive testing as described in claim 3, characterized in that, In S2, the extraction of the "worker" - shaped pattern on the auxiliary positioning label (4) includes: First, decompose the auxiliary positioning image I into three RGB channels to obtain I R 、I G 、I B three component images. Then, use the pre - selected "worker" - shaped template image I M to perform template matching operations on I B to find the area of the "worker" - shaped logo, and obtain the "worker" - shaped logo area image I B corresponding to the auxiliary positioning label (4); BR ; For I R Perform the same calculation on the image to obtain the image I of the "I"-shaped logo area corresponding to the auxiliary positioning laser lamp (2). RR .

5. The automatic assisted alignment method for X-ray nondestructive testing as described in claim 4, characterized in that, S3 includes: S31. Extraction of the line segments forming the "工" character logo: First, perform binary operations on the regional images I BR and the regional image I RR respectively. During the binary operation, use the Otsu method to automatically determine the threshold, and obtain the binary images I BRB and I RRB . Then, calculate the equations of the line segments forming the "工" character through the fast Hough transform; S32, Calculation of translation offset △x: Based on L R2 With L B2 The positional relationships and scaling conditions were calculated. S33, △y translation offset calculation: based on line segment L B2 The scaling can be calculated; S34, Calculation of △θ rotation offset: Based on line segment L R1 With L B1 The angle relationship is calculated.

6. The automatic assisted alignment method for X-ray nondestructive testing as described in claim 5, characterized in that, In S31, the binary image I RRB The equations formed by the line segments are: The top horizontal line segment is LR1:y R1 =k R1 x R1 +b R1 , x∈[a R1 c R1 ]、 The middle vertical line segment is LR2: y R2 =k R2 x R2 +b R2 , x∈[a R2 c R2 ]、 The bottom horizontal line segment is LR3:y R3 =k R3 x R3 +b R3 , x∈[a R3 c R3 ] L is calculated based on the system of line segment equations. R2 respectively with L R1 L R3 The intersection points are A and B, respectively. R1 (X) R1 ,Y R1 ) and A R2 (X) R2 ,Y R2 ).

7. The automatic assisted alignment method for X-ray nondestructive testing as described in claim 6, characterized in that, The equation of the line segments formed by "工" is calculated by fast Hough transform, and the binary image I BRB Equation of the line segments formed: The top horizontal line segment is LB1: y B1 =k B1 x B1 +b B1 , x∈[a B1 c B1 ]、 The middle vertical line segment is LB2: y B2 =k B2 x B2 +b B2 , x∈[a B2 c B2 ]、 The bottom horizontal line segment is LB3:y B3 =k B3 x B3 +b B3 , x∈[a B3 c B3 ]. L can be calculated from the system of equations for line segments. B2 respectively with L B1 L B3 The intersection points are A and B, respectively. B1 (X) B1 ,Y B1 ) and A B2 (X) B2 ,Y B2 ).

8. The automatic assisted alignment method for X-ray nondestructive testing as described in claim 7, characterized in that, S32 includes: the calculation of the left and right translation offset Δx is based on line segment L. R2 With L B2 The left and right position difference was calculated. Since the measured item was placed on the surface of the platform, the L in the "I" shaped pattern on the auxiliary positioning mark (4) and the "I" shaped pattern emitted by the auxiliary positioning laser light (2) were different. R2 With L B2 All line segments are perpendicular, therefore L R2 The horizontal position is represented by point A on its line segment. R1 Or A R2 The horizontal coordinate is used to represent its position, and similarly, L... B2 The horizontal position is represented by point A on its line segment. B1 Or A B2 The x-coordinate is used to represent its position, i.e., △x = |X B1 -X R1 | 9. The automatic assisted alignment method for X-ray nondestructive testing as described in claim 8, characterized in that, S33 includes: firstly, according to A B1 A B2 L was calculated B2 The length of the line segment l1 is obtained from actual measurement. The length of the line segment "|" in the "I" shaped pattern on the auxiliary positioning mark (4) is l2. Let the distance from the auxiliary positioning laser lamp (2) to the surface of the standard placed test object power module (5) be l0, then the following conditions are met: Therefore, the translation offset of △y is: .

10. The automatic assisted alignment method for X-ray nondestructive testing as described in claim 9, characterized in that, S34 includes: firstly, according to A R1 A R2 L can be calculated R2 The length of the line segment is l3; secondly, according to the trigonometric function relationship, the divergence angle of the auxiliary positioning laser lamp (2) is θ0, and l4 is the distance in space between the upper "one" end of the laser lamp "I" shape when the power module (5) is placed in standard and offset positions, then it satisfies: , , , Solving the four equations above simultaneously, we obtain the rotation offset: Δs is the difference in the vertical direction between the upper edge of the offset test object illuminated by the laser and the standard placement.

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