An x-ray non-destructive testing automated assist alignment system and method

Abstract

The present application relates to a kind of X-ray nondestructive testing automatic auxiliary alignment system and method, belong to measurement technical field.The present application includes: X ray source (1), auxiliary positioning laser lamp (2), visible light camera (3), auxiliary positioning mark paste (4), power module (5), object table (6) and flat panel detector (7).The present application is combined with automatic control and computer image processing technology, "G" shape graphic information is rich, can realize the calculation of multiple axis offset, simplifies the complexity of auxiliary tool in automatic auxiliary alignment, 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 described auxiliary positioning laser lamp (2) emits a red "I"-shaped pattern laser, the auxiliary positioning mark sticker (4) is printed with the same "I"-shaped pattern in blue color and is attached to the surface of the power module (5) of the test object. When the test object is placed without deviation, the red "I"-shaped pattern laser coincides with the "I"-shaped pattern on the auxiliary positioning mark sticker (4);

[0009] The visible light camera (3) is directly facing the auxiliary positioning mark sticker (4) on the power module (5) of the test object, and is used to acquire the coincidence condition between the "I"-shaped pattern laser and the "I"-shaped pattern on the auxiliary positioning mark sticker (4), so as to provide basic data for deviation calculation;

[0010] The described object stage (6) is used for carrying the power module (5) of the test object, and has at least three degrees of freedom of movement: front-back, left-right, and rotation.

[0011] The present invention further provides an X-ray non-destructive testing automatic auxiliary alignment method, which comprises: acquiring an auxiliary positioning image I, extracting the "I"-shaped pattern, calculating the offset, judging whether the offset is smaller than the minimum offset, and performing compensation movement of the object stage;

[0012] S1. Acquiring the auxiliary positioning image I refers to obtaining an RGB color image by taking a photo with the visible light camera (3);

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

[0014] S3. The described offset calculation includes extracting the line segments constituting the "I"-shaped mark, calculating the translation offset and the rotation offset, so as to form an offset parameter group (△x, △y, △θ), where △x represents the left-right translation offset, △y represents the front-back translation offset, and △θ represents the rotation offset;

[0015] S4. The step of judging whether the offset is smaller than the minimum offset is determined according to the accuracy of the actually calculated offset. During the cyclic compensation process, if 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 obtained from the 5 calculations;

[0016] S5. The described compensation movement of the object stage refers to moving the object stage in the opposite direction according to the calculated offset parameter group (△x, △y, △θ), so that the power module (5) of the test object is consistent with the standard placement position.

[0017] (III) Beneficial effects

[0018] The present invention proposes an X-ray non-destructive testing automatic auxiliary alignment system and method, which combines automatic control and computer image processing technologies. The I-shaped pattern has rich information and can realize the calculation of multi-axis offsets, simplify the complexity of auxiliary tools in automatic auxiliary alignment, and play an important role in non-destructive testing. Brief Description of the Drawings

[0019] Figure 1 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 is a flowchart of the X-ray non-destructive testing automatic alignment method;

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

[0022] Figure 4 is a schematic diagram of the proportional relationship of the Δy offset;

[0023] Figure 5 is a schematic top-view projection diagram of the laser lamp and the power module. Detailed Description of the Embodiments

[0024] To make the purposes, contents and advantages of the present invention clearer, the specific embodiments of the present invention are described in further detail below with reference to the accompanying drawings and embodiments.

[0025] The present invention discloses the proposed 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 mark sticker, a power module (tested object), a stage, and a flat panel detector. The main idea is to use the auxiliary laser lamp to project an "I"-shaped pattern on the tested object, calculate the displacement and angle difference of the tested object on the stage according to the deviation between the pattern and the auxiliary positioning mark sticker, and the stage performs compensation movement according to the difference value to realize the compensation for multiple manual placement errors of the tested object, that is, to achieve the purpose of automatic alignment for X-ray non-destructive testing of the power module.

[0026] The present invention proposes an X-ray non-destructive testing automatic auxiliary alignment system, comprising: an X-ray source (1), an auxiliary positioning laser lamp (2), a visible light camera (3), an auxiliary positioning mark sticker (4), a power 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 project an "I"-shaped pattern on the tested object, calculate the displacement and angle difference of the tested object on the stage (6) according to the deviation between the pattern and the auxiliary positioning mark sticker (4), and the stage (6) performs compensation movement according to the difference value to realize the compensation for multiple manual placement errors of the tested object, that is, to achieve the purpose of automatic alignment for X-ray non-destructive testing of the power module (5).

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

[0028] The auxiliary positioning laser lamp (2) emits a red "H"-shaped pattern laser, the auxiliary positioning label sticker (4) is printed with the same "H"-shaped pattern, the pattern is blue in color and attached to the surface of the power module (5) of the test object. When the test object is placed in a non-deviated (standard) position, the red "H"-shaped pattern laser coincides with the "H"-shaped pattern on the auxiliary positioning label sticker (4);

[0029] The visible light camera (3) faces the auxiliary positioning label sticker (4) on the power module (5) of the test object, and is configured to acquire the coincidence state between the "H"-shaped pattern laser and the "H"-shaped pattern on the auxiliary positioning label sticker (4), so as to provide basic data for deviation calculation;

[0030] The stage (6) is configured to carry the power module (5) of the test object, and has at least motion capabilities of three degrees of freedom: front-back, left-right, and rotation.

[0031] The process of the X-ray non-destructive testing automatic alignment method is as Figure 2 shown, which includes five key steps: acquiring the auxiliary positioning image I, extracting the "H"-shaped pattern, calculating the offset, judging whether the offset is less than the minimum offset, and performing compensation movement of the stage.

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

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

[0034] The extraction of the "H"-shaped pattern on the auxiliary positioning label sticker (4) includes: first performing RGB three-channel decomposition on the auxiliary positioning image I to obtain I R , I G , I B three component images, then using a pre-set "H"-shaped template image I M to perform template matching operation on I B to find the "H"-shaped mark region of I B , so as to obtain the "H"-shaped mark region image I corresponding to the auxiliary positioning label sticker (4) BR .

[0035] Similarly, performing the same calculation on the I R image can obtain the "H"-shaped mark region image I corresponding to the auxiliary positioning laser lamp (2)RR .

[0036] S3. The calculating the offset includes extracting the line segments constituting the "I"-shaped mark, calculating the translation offset and calculating the rotation offset, so as to form an offset parameter set (Δx, Δy, Δθ), where Δx represents the left-right translation offset, Δy represents the front-back translation offset, and Δθ represents the rotation offset.

[0037] S31. Further, the extracting the line segments constituting the "I"-shaped mark is as Figure 3 shown in the figure. First, the region image I BR and the region image I RR are subjected to binarization operation respectively. In the binarization process, the Otsu method is used to automatically determine the threshold value, so as to obtain the binarized image I BRB and I RRB , then the equations of the line segments constituting the "I"-shape are calculated through the fast Hough transform. The line segment composition equation of the binarized image I RRB is as follows:

[0038] The top transverse 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 transverse line segment is LR3: y R3 =k R3 x R3 +b R3 , x∈[a R3 , c R3

[0041] According to the line segment equation set, the intersection points of L R2 with L R1 and L R3 can be calculated, which are respectively A R1 (X R1 ,Y R1 ) and A R2 (X R2 ,Y R2 ).

[0042] Similarly, the equations of the line segments constituting the "I"-shape are calculated through the fast Hough transform, and the binarized 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) position can be represented by point A on its line segment. R1 Or A R2 The x-coordinate is used to represent its position, and similarly, L... B2 The left and right (horizontal) position 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 Δy translation offset is performed according to the scaling condition of the line segment L B2 . First, according to A B1 , A B2 , the length l1 of the L B2 line segment can be calculated. Through actual measurement, the length of the "|" line segment in the "I"-shaped pattern on the auxiliary positioning mark sticker (4) can be obtained as l2. As shown in Figure 4 , let the distance from the auxiliary positioning laser lamp (2) to the surface of the test object (power module (5)) placed at the standard position be l0, which satisfies: , so the Δy translation offset is: .

[0049] S34. Further, the calculation of the Δθ rotation offset is performed 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 L R2 line segment can be calculated. Secondly, according to the trigonometric function relationship, as shown in Figure 5 , the irradiation divergence angle of the auxiliary positioning laser lamp (2) is θ0, let l4 be the spatial distance of the end of the upper horizontal line of the "I" shape of the laser lamp between the standard placement and the offset placement of the power module (5), which satisfies: , , , , then by combining the above four equations, the rotation offset can be obtained as: . Δs is the difference in the vertical direction between the upper edge of the test object (power module) irradiated by the laser lamp in the offset placement state and that in the standard placement state.

[0050] S4. The condition of being less than the minimum offset is determined according to the accuracy of the actually calculated offset. Generally, according to experience, 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 obtained from the 5 calculations.

[0051] S5. The compensation movement of the stage is to move the stage in the opposite direction according to the calculated offset parameter group (Δx, Δy, Δθ), so that the test object power module (5) is consistent with the standard placement position.

[0052] Example 1:

[0053] The specific embodiments of the present invention are described below, but they are not intended to limit the specific implementation methods.

[0054] The present invention relates to an X-ray non-destructive testing automatic auxiliary alignment system and method, which mainly 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 module (5), a carrying stage (6), and a flat panel detector (7), as Figure 1 shown. The main idea is to use the auxiliary laser lamp 2 to project an "H"-shaped pattern on the tested object, calculate the displacement and angle difference of the tested object (power module) on the carrying stage according to the deviation between the pattern and the auxiliary positioning mark sticker 5, and the carrying stage (7) performs compensatory movement according to the difference value, so as to compensate for multiple manual placement errors of the tested object, that is, to achieve the purpose of automatic alignment for X-ray non-destructive testing of the power module.

[0055] Further, the X-ray source (1) is configured to emit X-rays, and the flat panel detector (7) is configured to receive X-rays and acquire X-ray images; the auxiliary positioning laser lamp (2) emits a red "H"-shaped pattern laser, the auxiliary positioning mark sticker (4) is printed with the same "H"-shaped pattern in blue color, and is attached to the surface of the tested power module (5). When the tested object is placed without deviation, the red "H"-shaped pattern laser coincides with the "H"-shaped pattern on the auxiliary positioning mark sticker (4); the visible light camera (3) directly faces the auxiliary positioning mark sticker (4) on the tested power module (5), and is configured to acquire the coincidence state between the "H"-shaped pattern laser and the "H"-shaped pattern on the auxiliary positioning mark sticker (4), so as to provide basic data for deviation calculation. The carrying stage (6) has at least three degrees of freedom of movement: forward and backward, left and right, and 360-degree rotation.

[0056] The process of the X-ray non-destructive testing automatic alignment method is as Figure 2 shown, which is characterized by comprising five key steps: acquiring auxiliary positioning image I, extracting the "H"-shaped pattern, calculating the offset, judging whether the offset is less than the minimum offset, and performing compensatory movement of the carrying stage.

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

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

[0059] The calculation of the offset described in (3) includes extracting the line segments constituting the "I"-shaped mark, calculating the translation offset, and calculating the rotation offset, forming an offset parameter group (△x, △y, △θ), where △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 constituting the "I"-shaped mark described above, as shown in Figure 3 , first perform processing on the area image I BR and the area image I RR respectively for binarization operation, during which the Otsu method is used to automatically determine the threshold value, to obtain the binarized images I BRB and I RRB , then calculate the equations of the line segments constituting the "I" shape through fast Hough transform, the line segment composition equations of the binarized image I RRB are:

[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 set, the intersection points of L R2 with L R1 and L R3 can be calculated, which are respectively A R1 (X R1 ,Y R1 ) and A R2 (X R2 ​​​,Y R2 .

[0065] Similarly, the equations of the line segments constituting the "I" shape are calculated by the fast Hough transform, and the binary image I BRB has the following line segment constituent 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 system of equations, which are respectively A B1 (X B1 ,Y B1 ) and A B2 (X B2 ,Y B2 ).

[0070] (32) Further, the calculation of the Δx translation offset is obtained by calculation according to the positional relationship and scaling condition of L R2 and L B2 . The calculation of the left-right translation offset Δx is obtained by calculation according to the left-right position difference between the line segment L R2 and L B2 . When the tested object is placed on the surface of the stage, the line segments L R2 and L B2 in the "I"-shaped pattern on the auxiliary positioning mark sticker (4) and the "I"-shaped pattern emitted by the auxiliary positioning laser lamp (2) are both in a vertical state, so the left-right (horizontal) position of L R2 can be represented by the abscissa of the point A R1 or A R2 on the line segment, and similarly for L B2 ​​​The left-right (horizontal) position can be represented by point A on its line segment B1 or A B2 through its abscissa, that is, Δx=|X B1 -X R1 |.

[0071] (33) Further, the calculation of the Δy translation offset is obtained based on the scaling condition of line segment L B2 . First, A B1 , A B2 can be used to calculate the length l1 of line segment L B2 , and the length of the "|" line segment in the "I"-shaped pattern on the auxiliary positioning label (4) can be obtained as l2 through actual measurement. As shown in Figure 4 , let the distance from the auxiliary positioning laser lamp (2) to the surface of the standard placed test object (power module (5)) be l0, which satisfies:

[0072]

[0073] Thus the Δy translation offset is:

[0074] .

[0075] (34) Further, the calculation of the Δθ rotation offset is obtained based on the included angle relationship between line segment L R1 and L B1 . First, A R1 , A R2 can be used to calculate the length l3 of line segment L R2 . Next, according to the trigonometric function relationship, as shown in Figure 5 , the irradiation divergence angle of the auxiliary positioning laser lamp (2) is θ0, let l4 be the spatial distance between the ends of the upper horizontal line of the "I" shape of the laser lamp when the power module (5) is placed in the standard position and in the offset position, which satisfies:

[0076]

[0077]

[0078]

[0079]

[0080] Then by combining the above four equations, the rotation offset can be obtained as:

[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 mark sticker (4), a power module (5), an object stage (6) and a flat panel detector (7); The X-ray source (1) is configured to emit X-rays, and the flat panel detector (7) is configured to receive X-rays and acquire an X-ray image; The auxiliary positioning laser lamp (2) emits a red "I"-shaped pattern laser, the auxiliary positioning mark sticker (4) is printed with the same "I"-shaped pattern, the pattern is blue and is attached to the surface of the power module (5) of the test object. When the test object is placed without deviation, the red "I"-shaped pattern laser coincides with the "I"-shaped pattern on the auxiliary positioning mark sticker (4); The visible light camera (3) faces the auxiliary positioning mark sticker (4) on the power module (5) of the test object, and is configured to acquire the coincidence state between the "I"-shaped pattern laser and the "I"-shaped pattern on the auxiliary positioning mark sticker (4), so as to provide basic data for deviation calculation; The object stage (6) is configured to carry the power module (5) of the test object, and has at least three degrees of freedom of movement: front-back movement, left-right movement, 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 project an "I"-shaped pattern onto the test object, and the displacement and angle difference of the test object on the object stage (6) are calculated according to the deviation between the pattern and the auxiliary positioning mark sticker (4). The object stage (6) performs compensation movement according to the difference value, so as to compensate for the errors caused by multiple manual placements of the test object, that is, to achieve the purpose of automatic alignment for X-ray non-destructive testing of the power 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, The method includes: acquiring an auxiliary positioning image I, extracting the "I"-shaped pattern, calculating the offset, judging whether the offset is smaller than the minimum offset, and performing compensation movement of the object stage; S1. Acquiring the auxiliary positioning image I is to obtain an RGB color image by taking a photo with the visible light camera (3); S2. The extraction of the "I"-shaped pattern is divided into the extraction of the "I"-shaped pattern on the auxiliary positioning mark sticker (4) and the extraction of the "I"-shaped pattern emitted by the auxiliary positioning laser lamp (2); S3. The calculating the offset includes extracting the line segments constituting the "I"-shaped mark, calculating the translation offset and calculating the rotation offset, so as to form an offset parameter group (Δx, Δy, Δθ), where Δx represents the left-right translation offset, Δy represents the front-back translation offset, and Δθ represents the rotation offset; S4. The judging whether the offset is smaller than the minimum offset is determined according to the accuracy of the actually calculated offset. During the cyclic compensation process, if 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 obtained from the 5 calculations; S5. The compensation movement of the object stage is to move the object stage in the opposite direction according to the calculated offset parameter group (Δx, Δy, Δθ), so that the power module (5) of the test object 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 the step S2, the extraction of the "I"-shaped pattern on the auxiliary positioning marker sticker (4) comprises: first performing RGB three-channel decomposition on the auxiliary positioning image I to obtain I R , I G , I B three component images, then performing template matching operation on I M using a pre-set "I"-shaped template image I B to find the region of the "I"-shaped marker in I B , so as to obtain the "I"-shaped marker region image I corresponding to the auxiliary positioning marker sticker (4) BR ; Perform the same calculation on I R the image to obtain the "H"-shaped mark region image I 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, The S3 includes: S31. Extraction of line segments forming the "工"-shaped marker: First, the regional image I BR and the regional image I RR are binarized respectively. During the binarization process, the Otsu method is used to automatically determine the threshold value, so as to obtain the binarized images I BRB and I RRB , and then the equations of the line segments forming the "工" shape are calculated through fast Hough transform; S32, Calculation of translation offset of △x: Based on binary image I RRB Middle vertical line segment L R2 With binary image I BRB Middle vertical line segment L B2 The positional relationships and scaling conditions were calculated. S33, △y translation offset calculation: based on line segment L B2 The scaling is calculated; S34, Calculation of △θ rotation offset: Based on binary image I RRB Middle top horizontal line segment L R1 With binary image I BRB Middle top horizontal line segment L B1 The angle relationship was 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 L R1 y=k R1 x+b R1 , x∈[a R1 c R1 ]、 The middle vertical line segment is L R2 y=k R2 x+b R2 , x∈[a R2 c R2 ]、 The bottom horizontal line segment is L R3 y=k R3 x+b R3 , x∈[a R3 c R3 ] L is calculated based on the system of equations for line segments. 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 equations of the line segments forming the "I-shape" are calculated through the fast Hough transform, for the binary image I BRB the line segment composition equation of: The top horizontal line segment is L B1 y=k B1 x+b B1 , x∈[a B1 c B1 ]、 The middle vertical line segment is L B2 y=k B2 x+b B2 , x∈[a B2 c B2 ]、 The bottom horizontal line segment is L B3 y=k B3 x+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 x-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, The step S33 includes: first, according to A B1 , A B2 calculating to obtain L B2 the length of the line segment l 1, the length of the "|" line segment in the "I"-shaped pattern on the auxiliary positioning marker sticker (4) obtained through actual measurement is l 2; let the distance from the auxiliary positioning laser lamp (2) to the surface of the power module (5) of the test object placed in a standard manner be l 0, which satisfies: , therefore, the Δy translation offset: .

10. The automatic assisted alignment method for X-ray nondestructive testing as described in claim 9, characterized in that, The step S34 includes: first, according to A R1 , A R2 , the length of line segment L can be calculated R2 l 3; second, according to the trigonometric function relationship, the irradiation divergence angle of the auxiliary positioning laser lamp (2) is θ0, and let l 4 be the spatial distance of the end of the upper horizontal line of the "I" shape of the laser lamp when the power supply module (5) is placed in the standard position and the offset position, which satisfies: , , , , then the above four equations are combined to obtain the rotational offset: ; Δs is the difference in the vertical direction between the position where the laser lamp irradiates the upper edge of the test object placed in the offset position and that in the standard placement position.​

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