CN-122016864-A - Automatic visual detection imaging device and method for foreign matters in cladding tube

CN122016864ACN 122016864 ACN122016864 ACN 122016864ACN-122016864-A

Abstract

The invention belongs to the field of visual detection, and in particular relates to an automatic visual detection imaging device and method for foreign matters in a cladding tube, wherein the device comprises a coaxial light source, an electric zoom lens and a camera; and two ends of the cladding tube are respectively provided with a set of coaxial light sources, an electric zoom lens and a camera, and the coaxial light sources arranged at the two ends of the cladding tube adopt light sources with different colors and different wave bands. The invention can accurately detect the foreign matters with the area more than or equal to 1mm < 2 > on the premise of no contact, avoid secondary pollution or physical damage to the pipeline, overcome the problems of limited depth of field and insufficient illumination in the detection of the inside of the cladding tube of the traditional optical system, ensure the detection to be free of blind areas, and can realize the whole domain visual detection of the inside of the cladding tube with the inner diameter of about 8.5mm and the length of about 4000 mm.

Inventors

PAN BIN
LI CHAO
WEI QIFEI
LIU BAOTONG
TIAN JIUCHENG
LIU JIE
GENG KUNFENG
QIU QIWEN
TANG FANGFANG

Assignees

中核北方核燃料元件有限公司

Dates

Publication Date: 20260512
Application Date: 20251125

Claims (10)

1. The automatic visual detection imaging device for the foreign matters in the cladding tube is characterized by comprising a coaxial light source (4), an electric zoom lens (9) and a camera (10), wherein the coaxial light source (4), the electric zoom lens (9) and the camera (10) are respectively arranged at two ends of the cladding tube (1), and the coaxial light sources (4) arranged at two ends of the cladding tube (1) adopt light sources with different colors and different wave bands.
2. An automatic visual inspection imaging apparatus for an interior foreign matter of a cladding tube according to claim 1, wherein the coaxial light source (4) is provided with a light source front-rear adjustment mechanism (7) and a light source up-down adjustment mechanism (8), and the light source front-rear adjustment mechanism (7) and the light source up-down adjustment mechanism (8) are adjusted to align the coaxial light source (4) with the center of the cladding tube body.
3. An automatic visual inspection imaging device for foreign matter inside a cladding tube according to claim 1, wherein the focusing position of the motorized zoom lens (9) is sequentially adjusted from the proximal end to the distal end, taken multiple times, covering the entire cladding tube body, the transition between adjacent focusing positions ensuring the depth of field overlap.
4. An automatic visual inspection imaging device of foreign matter inside a cladding tube according to claim 1, wherein the motorized zoom lens (9) is provided with a camera lens angle adjustment mechanism (13) for adjusting the motorized zoom lens (9) angle.
5. The automatic visual detection imaging device for the foreign matter inside the cladding tube according to claim 1, wherein the cameras (10) shoot at two ends of the cladding tube synchronously, the shot images are transmitted to the industrial personal computer processing unit, the industrial personal computer processing unit adopts a dual-mode foreign matter intelligent detection algorithm to perform image processing, whether the foreign matter exists is judged according to the image processing result, and any picture detects the foreign matter, namely, the disqualification of the tube body is judged.
6. The automatic vision detection imaging device for the foreign matter inside the cladding tube according to claim 5, wherein the image processing is performed by adopting a dual-mode foreign matter intelligent detection algorithm, and the specific method for judging the foreign matter is as follows: Aiming at a near-port area of a cladding tube, a traditional visual algorithm is adopted to quickly identify obvious foreign matters, a binarization treatment is adopted to extract foreign matters areas, characteristics such as the area and the gray level average value of a target are extracted, the number of black pixel points in a connected domain is calculated, and if the difference between the area and the number of the pixel points exceeds a set threshold value, the foreign matters are judged; and aiming at the far-end port area of the cladding tube, gamma correction is adopted for enhancement, detection is carried out after preliminary screening is carried out by using a traditional algorithm, confidence filtering is carried out by adopting deep learning, the confidence is fused and output, and a judging result is given.
7. An automatic visual inspection imaging device for foreign matter inside a cladding tube according to claim 1, wherein the camera (10) is provided with a camera up-down adjusting mechanism (11), a camera left-right adjusting mechanism (12) for adjusting the position of the camera (10).
8. An automatic visual inspection imaging device for foreign matter inside a cladding tube according to claim 1, further comprising a bracket (2) and a baffle plate (3), wherein the cladding tube (1) is laid on the bracket (2), the coaxial baffle plate (3) is arranged on the bracket (2), the cladding tube is intercepted by the coaxial baffle plate (3), the cladding tube (1) is stationary, the center of the cladding tube is close to a central coaxial line, and the inner universe of the cladding tube can be ensured to be covered by a light source.
9. An automated vision inspection imaging apparatus for alien substances inside a cladding tube according to claim 1, further comprising a cantilever box (6), the cantilever box (6) being mounted to the side of the cladding tube inspection area for viewing the inspection condition of the cladding tube inspection area.
10. A method of automatic visual inspection imaging of foreign matter inside a cladding tube, employing an automatic visual inspection imaging device of foreign matter inside a cladding tube according to any one of claims 1-9, the method comprising: s1, a cladding tube (1) is driven downwards along with a production line, the cladding tube is blocked by a baffle plate (3) until reaching a detection position, a sensor is arranged on a bracket (2) and is consistent with the position of the baffle plate (3) of the bracket, the cladding tube is sensed to a detection mechanism, and a signal is sent to an industrial personal computer; s2, the electric zoom lenses (9) at two ends are controlled by the industrial personal computer, zoom is sequentially carried out according to preset focal segments, a camera (10) shoots through the electric zoom lenses (9) and the coaxial light source (4), a plurality of groups of images are obtained, and the images are transmitted to the processing unit of the industrial personal computer; S3, the industrial personal computer processing unit processes the image by adopting a dual-mode foreign matter intelligent detection algorithm; and S4, triggering an alarm when any image detects the foreign matters, and if the foreign matters are not detected, lowering the baffle plate (3), continuing to flow downwards the cladding tube (1), so as to finish the detection of the foreign matters in the cladding tube.

Description

Automatic visual detection imaging device and method for foreign matters in cladding tube Technical Field The invention belongs to the field of visual detection, and particularly relates to an automatic visual detection imaging device and method for foreign matters in a cladding tube. Background The existing pipeline internal defect detection methods mainly comprise an endoscope and a video mirror penetration type detection, a single focus imaging system fixed focus photographing detection and the like, but the methods have obvious limitations on detecting the foreign matters in the cladding pipe with the inner diameter of about 8.5 mm and the length of 4 m, wherein the penetration type detection tool stretches into the pipe with the length of 4 m to cause serious limitation on the operation performance and abrasion of a workpiece to be detected, the narrow diameter limits the size of the endoscope, the image resolution and the visual field range are directly influenced, the depth of field of a fixed focus camera is limited, the inner wall of the pipe with the length of 4 m cannot be clearly shot, the area beyond the depth of field is in a fuzzy state, the contrast and the edge definition of the foreign matters are obviously reduced, the detection omission risk is increased, the depth of field problem is more serious along with the increase of the distance, the detection reliability of the far end area is obviously reduced, and the physical limitation makes the traditional single focus imaging system difficult to adapt to the whole-process high quality detection requirement of the long pipe. In addition, imaging in the tube is irregular, and the angles of light rays reaching the camera from different parts of the inner wall of the tube are different, so that the distances from the camera are different, and the inner wall of the tube is subjected to compression and stretching to different degrees under perspective projection. There may be multiple types, shapes, materials and sizes of foreign objects within the tube, and a single algorithm cannot accommodate such complex situations. Disclosure of Invention The invention aims to provide an automatic visual detection imaging device and method for foreign matters in a cladding tube, which can accurately detect the foreign matters with the area of more than or equal to 1mm 2 on the premise of no contact, avoid secondary pollution or physical damage to a pipeline, overcome the problems of limited depth of field and insufficient illumination in the detection of the inside of the cladding tube of a traditional optical system, ensure no blind area in detection, and realize the global visual detection of the inside of the cladding tube with the inner diameter of about 8.5mm and the length of about 4000 mm. The technical scheme for realizing the purpose of the invention comprises the following steps: The automatic visual detection imaging device for the foreign matters in the cladding tube comprises a coaxial light source, an electric zoom lens and a camera, wherein the coaxial light source, the electric zoom lens and the camera are respectively arranged at two ends of the cladding tube, and the coaxial light sources arranged at two ends of the cladding tube adopt light sources with different colors and different wave bands. Further, the coaxial light source is provided with a light source front-back adjusting mechanism and a light source up-down adjusting mechanism, and the light source front-back adjusting mechanism and the light source up-down adjusting mechanism are adjusted to enable the coaxial light source to be aligned with the center of the cladding tube body. Further, the focusing positions of the electric zoom lenses are sequentially adjusted from the near end to the far end, shooting is carried out for multiple times, the whole cladding tube body is covered, and the transition between the adjacent focusing positions ensures the overlapping of depth of field. Further, the electric zoom lens is provided with a camera lens angle adjusting mechanism for adjusting the angle of the electric zoom lens. Further, the camera shoots synchronously at two ends of the cladding tube, the shot images are transmitted to the industrial personal computer processing unit, the industrial personal computer processing unit adopts a dual-mode intelligent foreign matter detection algorithm to process the images, whether foreign matters exist or not is judged according to the image processing result, and whether any picture detects the foreign matters is judged that the tube body is unqualified. Further, the image processing is carried out by adopting a dual-mode foreign matter intelligent detection algorithm, and the specific method for judging the foreign matter is as follows: Aiming at a near-port area of a cladding tube, a traditional visual algorithm is adopted to quickly identify obvious foreign matters, a binarization treatment is adopted to extract foreign matters areas, ch