CN110813798A - Bar defect detection device and method based on vision - Google Patents
Bar defect detection device and method based on vision Download PDFInfo
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Abstract
The invention provides a bar defect detection device and method based on vision, which can be used for detecting defects of bars and comprises a feeding mechanism, a detection mechanism and an eliminating mechanism; the feeding mechanism is divided into a feeding section and a discharging section; the detection mechanism is arranged at the feeding section, and the rejection mechanism is arranged at the discharging section; the feeding mechanism comprises at least two driving wheels, the driving wheels are sequentially arranged on the feeding section and the discharging section to form a transmission path, the bar is transmitted from the feeding section to the discharging section along the transmission path through the driving wheels, the detection mechanism detects defects of the bar while the bar is transmitted, and the rejection mechanism is used for rejecting the bar out of the driving wheels when the bar has defects. Can go up unloading automatically, realized that the substandard product is rejected automation, and detect the bar when transmitting the bar, greatly improved detection efficiency.
Description
[ technical field ] A method for producing a semiconductor device
The invention relates to the technical field of defect detection, in particular to a bar defect detection device and method based on vision.
[ background of the invention ]
With the development of economic construction and the continuous progress of scientific technology, the manufacturing industry develops rapidly, the intelligent manufacturing is in the 4.0 era along with the industry, the intelligent manufacturing is in the way, the development of the intelligent manufacturing cannot leave high-quality raw materials, and bar materials are used as one of the raw materials for manufacturing parts, so that the occupied proportion is extremely high. During the production process of the bar stock, the surface of the product has more or less defects such as cracks, scratches and the like, which not only affect the appearance of the product, but also reduce the physical properties of the product.
But the existing bar defect detection device has insufficient automation degree and lower detection efficiency.
[ summary of the invention ]
The invention provides a bar defect detection device and method based on vision, aiming at solving the problem that the existing bar defect detection device is low in detection efficiency.
In order to solve the technical problems, the invention provides the following technical scheme: a bar defect detection device based on vision is used for detecting defects of bars and comprises a feeding mechanism, a detection mechanism and an eliminating mechanism; the feeding mechanism is divided into a feeding section and a discharging section; the detection mechanism is arranged at the feeding section, and the rejection mechanism is arranged at the discharging section; the feeding mechanism comprises at least two driving wheels, the at least two driving wheels are sequentially arranged at a feeding section and a discharging section to form a transmission path, the bar stock is transmitted from the feeding section to the discharging section along the transmission path through the at least two driving wheels, the detecting mechanism detects defects of the bar stock while the bar stock is transmitted, and the rejecting mechanism is used for rejecting the bar stock out of the driving wheels when the bar stock has defects.
Preferably, the feeding mechanism further comprises at least one driven wheel; at least one driven wheel is arranged between every two driving wheels.
Preferably, the detection mechanism comprises at least three defect cameras and at least six strip-shaped light sources; the defect shooting device surrounds the transmission route in a radial space plane in 360 degrees; the defect shooting device and the two strip-shaped light sources form a group, and the two strip-shaped light sources are oppositely arranged on two sides of the defect shooting device.
Preferably, the detection mechanism further comprises at least one diameter shooting device and at least one parallel backlight source; the parallel backlight source and the diameter shooting device are oppositely arranged on two sides of the transmission line.
Preferably, the detection mechanism further comprises an industrial personal computer; the industrial personal computer is in communication connection with the defect shooting device so as to detect the defect of the first bar image shot by the defect shooting device; and the industrial personal computer is in communication connection with the diameter shooting device so as to measure the diameter of the second bar image shot by the diameter shooting device.
Preferably, the rejecting mechanism comprises an electric cylinder device and a fork arm; the electric cylinder device is arranged on one side of the transmission line; one surface of the fork arm, which is close to the transmission path, is an inclined surface, one surface of the fork arm, which is far away from the transmission path, is in contact with the end surface of the electric cylinder device, and the fork arm is arranged between the at least two transmission wheels and is lower than the transmission wheels in height;
the electric cylinder device is in communication connection with the industrial personal computer, and when receiving a rejection signal sent by the industrial personal computer, the electric cylinder device drives the fork arm to jack up the bar so that the bar rolls down along the fork arm.
In order to solve the above technical problems, the present invention provides another technical solution as follows: a bar defect detection method based on vision is suitable for the bar defect detection device based on vision, and comprises the following steps:
step S1, rotating the driving wheel to transmit the bar stock;
step S2, shooting the bar stock to obtain a first bar stock image while transmitting the bar stock;
step S3, detecting defects of the bar stock according to the first bar stock image;
and step S4, if the defect of the bar stock is detected, removing the bar stock.
Preferably, in step S3, the defect detection of the bar material according to the first bar material image is performed by:
step S301, analyzing the first bar image to judge whether the bar has defects;
step S302, if the defect exists, the bar stock is positioned to determine a target area where the defect is located;
step S303, according to the target area, performing image segmentation on the first bar image to obtain a defect image;
step S304, extracting defect characteristics from the defect image; the defect characteristics at least comprise gray values, shapes and textures of the defect images;
and S305, classifying the bar stock according to the defect characteristics.
Preferably, the following steps may be further included before step S301:
step S301a, performing distortion correction processing on the first bar stock image to obtain a corrected image;
step S301b, performing image enhancement processing on the corrected image to obtain a target image;
and step S301 is specifically: analyzing the target image to judge whether the bar stock has defects;
and step S303 specifically comprises: and according to the target area, carrying out image segmentation on the target image to obtain a defect image.
Preferably, the following steps may be further included after step S2:
step S2a, shooting the bar stock to obtain a second bar stock image while transmitting the bar stock;
and step S2b, calculating the diameter of the bar stock according to the second bar stock image.
Compared with the prior art, the bar defect detection device and method based on vision provided by the invention have the following beneficial effects:
the invention provides a bar defect detection device based on vision, which belongs to the technical field of bar defect detection and is used for detecting defects of bars and comprises a feeding mechanism, a detection mechanism and an eliminating mechanism, wherein the feeding mechanism is divided into a feeding section and a discharging section, the detection mechanism is arranged at the feeding section, and the eliminating mechanism is arranged at the discharging section; the feeding mechanism comprises at least two driving wheels, the driving wheels are sequentially arranged on the feeding section and the discharging section to form a transmission path, the bar is transmitted from the feeding section to the discharging section along the transmission path through the driving wheels, the detection mechanism detects defects of the bar while the bar is transmitted, and the rejection mechanism is used for rejecting the bar out of the driving wheels when the bar has defects. The feeding mechanism is in butt joint with a production line of bars, the bars directly enter the feeding mechanism after being produced, defect detection is carried out through the detection mechanism, if the bars are detected to have defects, the driving wheels are eliminated from the bars through the eliminating mechanism, the problems that an existing bar defect detection device is insufficient in automation degree and cannot automatically feed and unload are effectively solved, defective product elimination automation is realized, the detection efficiency is improved, the overall aesthetic feeling of the bars is guaranteed, the physical performance of the bars is improved, and the workload of detection personnel is reduced. In addition, the bar stock is conveyed and detected at the same time, the conveying of the bar stock is not interrupted, and the detection efficiency of the bar stock defect detection device can be further improved. In addition, the driving wheels are arranged in sequence, so that a small amount of driving wheels can be used for transmitting the bars, the complexity of the feeding mechanism is simplified, the space can be saved, the space utilization rate is improved, and the heat dissipation efficiency is increased.
In the vision-based bar defect detection device provided by the invention, the feeding mechanism further comprises at least one driven wheel, at least one driven wheel is arranged between every two driving wheels, wherein the bar is arranged on the driving wheels and the driven wheels, the driving wheels rotate to drive the bar to be transmitted, and the driven wheels assist the functions of bearing and passively transmitting the bar, so that the bar can be stably transmitted according to a transmission route, particularly the transmission of a longer bar and the transmission of a longer distance, and the stability is stronger.
In the bar defect detection device based on vision, the detection mechanism comprises at least three defect shooting devices and at least six bar-shaped light sources, wherein the at least three defect shooting devices are used for shooting the bar to detect the defect of the bar, the defect shooting devices surround the radial space plane of the transmission line for 360 degrees, 360-degree comprehensive shooting of the bar can be ensured, missing shooting is avoided, and the detection mode is opposite to the detection of a single camera, the bar does not need spiral rolling transmission, the detection speed is greatly improved, and the detection stability is improved; two bar light sources are arranged on two sides of the defect shooting device relatively, so that the uniform illumination of the bar can be ensured, and the shooting of the defect detection device is facilitated.
In the bar defect detection device based on vision, the detection mechanism further comprises at least one diameter shooting device and at least one parallel backlight source, wherein the diameter shooting device is used for shooting the bar to measure the diameter of the bar, so that the diameter of the bar can be measured while defect detection is not influenced, and the measurement efficiency is improved; the light emitting directions of the parallel backlight sources are consistent, the phenomenon of blunting at the edge of the bar is avoided to a great extent, and the detection precision is improved.
In the bar defect detection device based on vision, the detection mechanism further comprises an industrial personal computer, the industrial personal computer is in communication connection with the defect shooting device to detect a defect of a first bar image shot by the defect shooting device, the industrial personal computer is in communication connection with the diameter shooting device to detect a defect of a second bar image shot by the diameter shooting device, and the industrial personal computer is in unified communication connection with the defect shooting device and the diameter shooting device, so that the working integrity of the defect shooting device and the diameter shooting device can be improved, and the detection efficiency of the bar defect detection device is improved.
In the visual-based bar defect detection device provided by the invention, the rejecting mechanism comprises an electric cylinder device and a fork arm, the electric cylinder device is arranged on one side of the transmission line, one surface of the fork arm, which is close to the transmission line, is an inclined surface, one surface of the fork arm, which is far away from the transmission line, is in contact with the end surface of the electric cylinder device, the fork arm is arranged between at least two transmission wheels and is lower than the transmission wheels, and when the electric cylinder device receives a rejecting signal sent by an industrial personal computer, the fork arm is driven to jack up a bar so that the bar rolls down along the fork arm. Carry out unified communication connection to defect shooting device, diameter shooting device and electric cylinder device by the industrial computer, link up the detection and the rejection of bar, can in time reject when detecting that the bar has the defect, promoted the cooperation between each mechanism, improve this bar defect detecting device's detection efficiency. In addition, when the defective products are not removed, the fork arms are not in contact with the bars, so that the defective products are not removed, and the normal transmission of the bars is guaranteed.
The invention also provides a bar defect detection method based on vision, which has the same beneficial effects as the bar defect detection device based on vision, and the details are not repeated herein. In addition, the industrial personal computer can also perform distortion correction processing on the first bar image shot by the defect shooting device, can further improve the detection precision, and then performs image enhancement processing on the image after the distortion correction processing, so that the influence of image noise and uneven illumination on imaging can be reduced.
[ description of the drawings ]
Fig. 1 is a schematic structural diagram of a bar defect detecting device based on vision according to a first embodiment of the present invention.
FIG. 2 is a schematic structural diagram of a feeding mechanism of a visual-based bar defect detecting apparatus according to a first embodiment of the present invention.
FIG. 3 is a schematic structural diagram of a detecting mechanism of a visual-based bar defect detecting apparatus according to a first embodiment of the present invention.
FIG. 4 is a schematic structural diagram of a rejecting mechanism of a visual-based bar defect detecting apparatus according to a first embodiment of the present invention.
FIG. 5 is a flowchart illustrating a method for detecting defects of bar materials based on vision according to a second embodiment of the present invention.
FIG. 6 is a first flowchart illustrating a step of defect detection of the first bar image according to a second embodiment of the present invention.
FIG. 7 is a second flowchart illustrating the steps of detecting defects in the first bar image according to a second embodiment of the present invention.
FIG. 8 is a flow chart illustrating the steps of measuring the diameter of a second image of a bar according to a third embodiment of the present invention.
The attached drawings indicate the following:
10. a bar defect detection device based on vision; 11. a feeding mechanism; 12. a detection mechanism; 13. a rejection mechanism; 14. a bar stock;
111. a driving wheel; 112. an intermediate shaft; 113. a belt pulley; 114. a motor device; 121. a defect shooting device; 122. a strip light source; 123. a diameter photographing device; 124. a parallel backlight source; 125. an industrial personal computer; 131. an electric cylinder device; 132. a yoke; 133. and a defective basket.
[ detailed description ] embodiments
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Referring to fig. 1 and 2, a first embodiment of the present invention provides a visual-based bar defect detecting apparatus 10 for detecting defects of a bar. The device comprises a feeding mechanism 11, a detection mechanism 12 and a rejection mechanism 13; the feeding mechanism 11 is divided into a feeding section A and a discharging section B; the detection mechanism 12 is arranged at the feeding section A, and the rejection mechanism 13 is arranged at the discharging section B; the feeding mechanism 11 comprises at least two driving wheels 111, the at least two driving wheels 111 are sequentially arranged on the feeding section A and the discharging section B to form a transmission path, the bar 14 is transmitted from the feeding section A to the discharging section B along the transmission path through the at least two driving wheels 111, the detecting mechanism 12 detects defects of the bar 14 while the bar 14 is transmitted, and the removing mechanism 14 is used for removing the driving wheels 111 from the bar 14 when the bar 14 has defects.
It can be understood that the feeding mechanism 11 is butted with a production line of the bar 14, the bar 14 directly enters the feeding mechanism 11 after being produced, defect detection is carried out through the detection mechanism 12, and if the defect of the bar 14 is detected, the bar 14 is rejected out of the driving wheel 111 through the rejection mechanism 13. Because the detection mechanism 12 is arranged at the feeding section a, and the rejecting mechanism 13 is arranged at the discharging section B, the bar 14 passes through the detection mechanism 12 when being transmitted on the feeding mechanism 11, at this time, the detection mechanism 12 detects defects of the bar 14, when the detection mechanism 12 detects that the bar 14 has defects, the bar 14 passes through the detection mechanism 12 and then passes through the rejecting mechanism 13, and the rejecting mechanism 13 rejects the bar 14.
Alternatively, the driving wheels 111 can drive the bar 14 to transmit through self-rotation, that is, each driving wheel 111 rotates independently. Of course, the driving wheel 111 can be driven by the motor to rotate simultaneously, as long as the driving wheel 111 can be rotated to drive the bar 14 to move according to the conveying direction. For example, in the present embodiment, the driving wheel 111 is connected to a motor for rotation.
Specifically, the driving wheel 111 may be a U-shaped rubber roll shaft, and of course, the driving wheel 111 may also be other rollers as long as it is sufficient to bear the bar 14 and drive the bar 14 to transmit.
Based on above-mentioned bar defect detection device 10 based on vision, can effectively solve current bar defect detection device degree of automation not enough, the unable problem of unloading in the automation, realized that the substandard product is rejected the automation, improved detection efficiency, the whole aesthetic feeling of guarantee bar improves the physical properties of bar, has reduced measurement personnel's work load. In addition, the bar stock is conveyed and detected at the same time, the conveying of the bar stock is not interrupted, and the detection efficiency of the bar stock defect detection device can be further improved. In addition, the driving wheels 111 are arranged in sequence, so that a small number of driving wheels 111 can be used for conveying the bars, the complexity of the feeding mechanism 11 is simplified, the space is saved, the space utilization rate is improved, and the heat dissipation efficiency is increased.
In one embodiment, the feeding mechanism 11 further includes at least one driven wheel (not shown); at least one driven wheel is arranged between every two driving wheels 111. The driven wheel is enabled to assist the functions of bearing and passively conveying the bars, so that the bars 14 can be stably conveyed according to a conveying route, and particularly, the conveying of long bars and the conveying of long distances are more stable.
Specifically, the driven wheel may be a U-shaped rubber roll shaft like the driving wheel 111, and of course, the driving wheel 111 may be other rollers as long as the requirement of bearing the bar 14 and passively conveying the bar 14 is met.
With continued reference to fig. 2, as an embodiment, the feeding mechanism 11 further includes an intermediate shaft 112, a plurality of pulleys 113, and a motor device 114; the intermediate shaft 112 is connected with a belt wheel key of the belt wheel 113; the driving wheel 111 is connected with the other belt wheel key of the belt wheel 113 through a bearing; the motor device 114 is connected with the intermediate shaft 112 through a coupler, the motor device 114 drives the intermediate shaft 112 to rotate, and the intermediate shaft 112 drives the driving wheel 111 to rotate through the belt pulley 113 so as to form a transmission path for transmitting the bar stock 14.
Specifically, the pulley 113 includes two pulleys vertically distributed and a belt, and the pulley 113 performs transmission in a half-crossed transmission manner.
It will be understood that the speed of travel of the bar 14 is determined by the speed of rotation of the motor means 114, which can be adjusted according to the actual requirements and is not limited thereto.
By implementing the above embodiment, the motor device 114 drives the intermediate shaft 112 to rotate, and the intermediate shaft 112 drives the driving wheel 111 to rotate through the belt pulley 113, so that the synchronism of the rotation of the driving wheel 111 can be maintained, and the smoothness of the bar 14 transmission can be further improved.
Referring to fig. 3, the detecting mechanism 12 includes at least three defect cameras 121 and at least six strip light sources 122; the defect photographing device 121 surrounds the transmission route in a radial space plane in 360 degrees; a defect camera 121 and two strip light sources 122 are combined, and the two strip light sources 122 are oppositely arranged at two sides of the defect camera 121.
Specifically, the defect capturing device 121 may be composed of an industrial camera and a general lens, or may be other devices, as long as the defect detection is not affected by the first bar image captured by the bar 14.
It can be understood that at least three defect shooting devices 121 are used for shooting the bar 14 to detect the defect of the bar, the defect shooting devices 121 surround the bar 14 in a 360-degree manner on the radial spatial plane of the transmission route, 360-degree overall shooting of the bar 14 can be guaranteed, missing shooting is avoided, and compared with the detection of a single camera, the detection mode of the bar 14 does not need spiral rolling transmission, the detection speed is greatly improved, and the detection stability is improved; two bar light sources 122 are arranged on two sides of the defect shooting device 121 relatively, so that the uniform illumination of the bar can be ensured, and the shooting of the defect detection device is facilitated.
Specifically, the bar light source 122 is perpendicular to the transmission line, so that a low-angle light source is formed, thereby avoiding shadow generation to influence the shooting of the defect shooting device 121, and improving the shooting effect of the defect shooting device 121.
Specifically, the detection mechanism 12 includes a three-defect imaging device 121; the adjacent defect cameras 121 are spaced apart by 120 ° and are offset in the axial direction of the transport path.
It is understood that the strip light sources 122 are grouped into two sets, and are oppositely disposed at two sides of the defect capturing device 121.
It can be understood that because the section of bar 14 is the cambered surface and has very high reflection phenomenon, can have the uneven phenomenon of shadow and illumination in the shooting process, consequently, above-mentioned defect shooting device 121's the mode of placing can 360 comprehensive shoot bar 14, avoids taking a picture neglectedly, can prevent again that each defect shooting device 121 from intervening each other and leading to influencing the formation of image, can improve detection efficiency.
In one embodiment, the detection mechanism 12 further comprises at least one diameter camera 123 and at least one parallel backlight 124; the parallel backlight 124 and the diameter shooting device 123 are oppositely arranged at two sides of the transmission line.
Specifically, the diameter shooting device 123 may be composed of an industrial camera and a telecentric lens, and compared with a common lens, the telecentric lens is adopted to reduce the imaging distortion degree, improve the image resolution, reduce the imaging distortion degree and reduce the perspective error, thereby greatly improving the diameter measurement precision.
It can be understood that the diameter shooting device 123 is used for shooting the bar 14 to measure the diameter of the bar, and can measure the diameter of the bar 14 without affecting the defect detection, thereby improving the detection efficiency; the light emitting directions of the parallel backlight sources 124 are consistent, so that the phenomenon of blunting at the edge of the bar 14 is avoided to a great extent, and the detection precision is improved.
With continued reference to fig. 3, as an embodiment, the detection mechanism 12 further includes an industrial personal computer 125; the industrial personal computer 125 is in communication connection with the defect shooting device 121 to detect the first bar image shot by the defect shooting device 121; and the industrial personal computer 125 is in communication connection with the diameter shooting device 123 so as to measure the diameter of the second bar stock image shot by the diameter shooting device 123.
It can be understood that the industrial personal computer 125 is in unified communication connection with the defect shooting device 121 and the diameter shooting device 123, so that the working integrity of the defect shooting device 121 and the diameter shooting device 123 can be improved, and the detection efficiency of the bar defect detection device 10 can be improved.
Referring to fig. 2, 3 and 4, the rejecting mechanism 13 includes an electric cylinder device 131 and a yoke 132; the electric cylinder device 131 is arranged on one side of the transmission line; one surface of the fork arm 132 close to the transmission line is an inclined surface, and one surface of the fork arm 132 departing from the transmission line is in end surface contact with the electric cylinder device 131; the fork arm 132 is arranged between the at least two driving wheels 111 and is lower than the driving wheels 111 in height; the electric cylinder device 131 is in communication connection with the industrial personal computer 125; when the electric cylinder device 131 receives the rejection signal sent by the industrial personal computer 125, the fork arm 132 is driven to jack up the bar 14, so that the bar 14 rolls down along the fork arm 132.
It can be understood that the industrial personal computer 125 is used for carrying out unified communication connection on the defect shooting device 121, the diameter shooting device 123 and the electric cylinder device 131, the detection and rejection of the bar 14 are linked, the bar 14 can be rejected in time when the defect exists in the bar 14, the matching among mechanisms is improved, and the detection efficiency of the bar defect detection device 10 is improved. In addition, in the non-rejection state, the fork arm 132 is not in contact with the bar 14, so that the normal transmission of the bar 14 is ensured while the rejection of defective products is not influenced.
With continued reference to fig. 4, as an embodiment, the rejecting mechanism 13 further includes a defective basket 133; defective baskets 133 are provided on opposite sides of the transport path so that the bars 14 fall to the defective baskets 133 as they roll down the fork arms 132.
Specifically, the defective basket 133 may be a square, a rectangular parallelepiped, or an ellipsoid in shape as long as the defective basket 133 can accommodate the rod material 14, and the shape of the defective basket 133 is not particularly limited.
It will be appreciated that the defective baskets 133 provide a uniform collection of the defective bars 14 for subsequent processing of the bars 14.
Referring to fig. 5, a second embodiment of the present invention provides a method for detecting defects of bar material based on vision, which includes the following steps:
step S1, rotating the driving wheel 111 to transfer the bar 14;
step S2, while the bar 14 is being transported, photographing the bar 14 to obtain a first bar image;
step S3, detecting defects of the bar 14 according to the first bar image;
in step S4, if the defect of the bar 14 is detected, the bar 14 is removed.
Referring to FIG. 6, as an embodiment, step S3 detects defects in the bar 14 based on the first bar image by:
step S301, analyzing the first bar image to judge whether the bar 14 has a defect; if yes, executing steps S302-S305; otherwise, the flow is ended;
step S302, defect positioning is carried out on the bar 14 to determine a target area where the defect is located;
step S303, according to the target area, performing image segmentation on the first bar image to obtain a defect image;
step S304, extracting defect characteristics from the defect image; wherein the defect characteristics at least comprise gray values, shapes and textures of the defect images;
step S305, the bar 14 is classified according to the defect characteristics.
Specifically, the image segmentation of the first bar image may be performed by using an edge detection algorithm in which a Canny operator is fused with morphology, or may be performed by using other algorithms as long as the defect image corresponding to the target region is segmented from the first bar image.
It is understood that the defect image after image segmentation still has some false edges or false defects, and in this case, as an embodiment, the false edges or false defects may be removed by some denoising algorithms, such as a mean filtering algorithm, a median filtering algorithm, a wiener filtering algorithm, and the like, which are not limited in this respect.
Specifically, as an implementation manner, the bar stock 14 is classified according to the defect features, a group of preset features may be selected for training of a classifier, and then the defect features are input into the trained classifier to determine whether the defect features are matched with a certain feature in the preset features, and if so, the category corresponding to the feature is the category corresponding to the bar stock 14.
Referring to fig. 7, as an embodiment, before step S301, the following steps may be further included:
step S301a, performing distortion correction processing on the first bar image to obtain a corrected image;
step S301b, performing image enhancement processing on the corrected image to obtain a target image;
and step S301 is specifically: analyzing the target image to judge whether the bar 14 has defects;
and step S303 specifically comprises: and performing image segmentation on the target image according to the target area to obtain a defect image.
It can be understood that the image of the first bar stock taken by the defect camera (industrial camera) will be distorted to some extent, thereby reducing the accuracy of defect detection. Therefore, as an embodiment, the distortion correction processing may be performed on the first bar image according to the following equations (1) and (2).
Wherein (X)w,Yw,Zw) Is the coordinates of the world coordinate system, (x, y) is the coordinates of the image coordinate system of the first bar image, ZcFor industrial cameras relative to the groundHeight, f is focal length of the industrial camera, R is rotation matrix of the industrial camera, (u, v) is coordinates in pixel coordinate system of the first bar image, (u ', v') is coordinates in pixel coordinate system of the corrected image after distortion correction processing, and point (u;)0,v0) Is the intersection of the optical axis of the industrial camera and the image plane, i.e. the principal point, dxIs the physical dimension of the pixel in the x-axis direction, dyIs the physical size of the pixel in the y-axis direction, k1、k2The first two orders of the distortion parameter k, respectively.
It is understood that enhancing the useful information in the image can improve the visual effect of the image, such as subjecting the corrected image to image enhancement processing, so that the industrial personal computer 125 can further determine whether the defect exists. As an embodiment, the corrected image may be subjected to image enhancement processing by a frequency domain method or a spatial domain method to obtain a target image. Of course, other algorithms can be used for image enhancement processing on the corrected image, as long as the image enhancement processing on the corrected image is satisfied, and the influence of image noise and uneven illumination on imaging is reduced.
In this embodiment, the industrial personal computer 125 can perform the distortion correction processing on the first bar image captured by the defect imaging device 121, and can further improve the detection accuracy, and then perform the image enhancement processing on the image after the distortion correction processing, and can reduce the influence of the image noise and the uneven illumination on the imaging.
Referring to fig. 8, as an embodiment, the following steps may be further included after step S2:
step S2a, while the bar 14 is being transported, shooting the bar 14 to obtain a second bar image;
step S2b, the diameter of the bar 14 is calculated from the second bar image.
In the embodiments provided herein, it should be understood that "B corresponding to a" means that B is associated with a from which B can be determined. It should also be understood, however, that determining B from a does not mean determining B from a alone, but may also be determined from a and/or other information.
It should be appreciated that reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Those skilled in the art should also appreciate that the embodiments described in this specification are exemplary and alternative embodiments, and that the acts and modules illustrated are not required in order to practice the invention.
In various embodiments of the present invention, it should be understood that the sequence numbers of the above-mentioned processes do not imply an inevitable order of execution, and the execution order of the processes should be determined by their functions and inherent logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.
The flowchart and block diagrams in the figures of the present application illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present application. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will be understood that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.
Compared with the prior art, the bar defect detection device and method based on vision provided by the invention have the following beneficial effects:
1. the invention provides a bar defect detection device based on vision, which belongs to the technical field of bar defect detection and is used for detecting defects of bars and comprises a feeding mechanism, a detection mechanism and an eliminating mechanism, wherein the feeding mechanism is divided into a feeding section and a discharging section, the detection mechanism is arranged at the feeding section, and the eliminating mechanism is arranged at the discharging section; the feeding mechanism comprises at least two driving wheels, the driving wheels are sequentially arranged on the feeding section and the discharging section to form a transmission path, the bar is transmitted from the feeding section to the discharging section along the transmission path through the driving wheels, the detection mechanism detects defects of the bar while the bar is transmitted, and the rejection mechanism is used for rejecting the bar out of the driving wheels when the bar has defects. The feeding mechanism is in butt joint with a production line of bars, the bars directly enter the feeding mechanism after being produced, defect detection is carried out through the detection mechanism, if the bars are detected to have defects, the driving wheels are eliminated from the bars through the eliminating mechanism, the problems that an existing bar defect detection device is insufficient in automation degree and cannot automatically feed and unload are effectively solved, defective product elimination automation is realized, the detection efficiency is improved, the overall aesthetic feeling of the bars is guaranteed, the physical performance of the bars is improved, and the workload of detection personnel is reduced. In addition, the bar stock is conveyed and detected at the same time, the conveying of the bar stock is not interrupted, and the detection efficiency of the bar stock defect detection device can be further improved. In addition, the driving wheels are arranged in sequence, so that a small amount of driving wheels can be used for transmitting the bars, the complexity of the feeding mechanism is simplified, the space can be saved, the space utilization rate is improved, and the heat dissipation efficiency is increased.
2. In the vision-based bar defect detection device provided by the invention, the feeding mechanism further comprises at least one driven wheel, at least one driven wheel is arranged between every two driving wheels, wherein the bar is arranged on the driving wheels and the driven wheels, the driving wheels rotate to drive the bar to be transmitted, and the driven wheels assist the functions of bearing and passively transmitting the bar, so that the bar can be stably transmitted according to a transmission route, particularly the transmission of a longer bar and the transmission of a longer distance, and the stability is stronger.
3. In the bar defect detection device based on vision, the detection mechanism comprises at least three defect shooting devices and at least six bar-shaped light sources, wherein the at least three defect shooting devices are used for shooting the bar to detect the defect of the bar, the defect shooting devices surround the radial space plane of the transmission line for 360 degrees, 360-degree comprehensive shooting of the bar can be ensured, missing shooting is avoided, and the detection mode is opposite to the detection of a single camera, the bar does not need spiral rolling transmission, the detection speed is greatly improved, and the detection stability is improved; two bar light sources are arranged on two sides of the defect shooting device relatively, so that the uniform illumination of the bar can be ensured, and the shooting of the defect detection device is facilitated.
4. In the bar defect detection device based on vision, the detection mechanism further comprises at least one diameter shooting device and at least one parallel backlight source, wherein the diameter shooting device is used for shooting the bar to measure the diameter of the bar, so that the diameter of the bar can be measured while defect detection is not influenced, and the measurement efficiency is improved; the light emitting directions of the parallel backlight sources are consistent, the phenomenon of blunting at the edge of the bar is avoided to a great extent, and the detection precision is improved.
5. In the bar defect detection device based on vision, the detection mechanism further comprises an industrial personal computer, the industrial personal computer is in communication connection with the defect shooting device to detect a defect of a first bar image shot by the defect shooting device, the industrial personal computer is in communication connection with the diameter shooting device to detect a defect of a second bar image shot by the diameter shooting device, and the industrial personal computer is in unified communication connection with the defect shooting device and the diameter shooting device, so that the working integrity of the defect shooting device and the diameter shooting device can be improved, and the detection efficiency of the bar defect detection device is improved.
6. In the visual-based bar defect detection device provided by the invention, the rejecting mechanism comprises an electric cylinder device and a fork arm, the electric cylinder device is arranged on one side of the transmission line, one surface of the fork arm, which is close to the transmission line, is an inclined surface, one surface of the fork arm, which is far away from the transmission line, is in contact with the end surface of the electric cylinder device, the fork arm is arranged between at least two transmission wheels and is lower than the transmission wheels, and when the electric cylinder device receives a rejecting signal sent by an industrial personal computer, the fork arm is driven to jack up a bar so that the bar rolls down along the fork arm. Carry out unified communication connection to defect shooting device, diameter shooting device and electric cylinder device by the industrial computer, link up the detection and the rejection of bar, can in time reject when detecting that the bar has the defect, promoted the cooperation between each mechanism, improve this bar defect detecting device's detection efficiency. In addition, when the defective products are not removed, the fork arms are not in contact with the bars, so that the defective products are not removed, and the normal transmission of the bars is guaranteed.
7. In the bar defect detection device based on vision, the detection mechanism comprises three defect shooting devices, the adjacent defect shooting devices are arranged at intervals of 120 degrees and are staggered in the axial direction of the transmission line, the arrangement mode can comprehensively shoot the bar at 360 degrees, the missing shooting is avoided, the imaging influence caused by the mutual interference among the defect shooting devices can be prevented, and the detection efficiency can be improved. In addition, the bar-shaped light is vertical to the transmission line, so that a low-angle light source is formed, shadow is prevented from being generated, the shooting of the defect shooting device is influenced, and the shooting effect of the defect shooting device can be improved.
8. In the visual-based bar defect detection device provided by the invention, the rejecting mechanism further comprises a defective basket, the defective basket is arranged on the opposite side of the transmission line, so that bars fall to the defective basket when rolling down along the fork arms, the defective basket is used for uniformly collecting the detected defective bars, and the subsequent treatment of the bars is facilitated.
9. The invention also provides a bar defect detection method based on vision, which has the same beneficial effects as the bar defect detection device based on vision, and the details are not repeated herein. In addition, the industrial personal computer can also perform distortion correction processing on the first bar image shot by the defect shooting device, can further improve the detection precision, and then performs image enhancement processing on the image after the distortion correction processing, so that the influence of image noise and uneven illumination on imaging can be reduced.
The device and the method for detecting the bar defect based on the vision disclosed by the embodiment of the invention are described in detail, the principle and the implementation mode of the invention are explained by applying specific examples, and the description of the embodiment is only used for helping to understand the method and the core idea of the invention; meanwhile, for the persons skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present description should not be construed as a limitation to the present invention, and any modification, equivalent replacement, and improvement made within the principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. The utility model provides a bar defect detecting device based on vision for carry out defect detection to the bar, its characterized in that: comprises a feeding mechanism, a detection mechanism and a rejection mechanism; the feeding mechanism is divided into a feeding section and a discharging section; the detection mechanism is arranged at the feeding section, and the rejection mechanism is arranged at the discharging section;
the feeding mechanism comprises at least two driving wheels, the at least two driving wheels are sequentially arranged at a feeding section and a discharging section to form a transmission path, the bar stock is transmitted from the feeding section to the discharging section along the transmission path through the at least two driving wheels, the detecting mechanism detects defects of the bar stock while the bar stock is transmitted, and the rejecting mechanism is used for rejecting the bar stock out of the driving wheels when the bar stock has defects.
2. A vision-based bar defect inspection apparatus as defined in claim 1, wherein: the feeding mechanism also comprises at least one driven wheel; at least one driven wheel is arranged between every two driving wheels.
3. A vision-based bar defect inspection apparatus as defined in claim 1, wherein: the detection mechanism comprises at least three defect shooting devices and at least six strip-shaped light sources; the defect shooting device surrounds the transmission route in a radial space plane in 360 degrees; the defect shooting device and the two strip-shaped light sources form a group, and the two strip-shaped light sources are oppositely arranged on two sides of the defect shooting device.
4. A vision-based bar defect inspection apparatus as defined in claim 3, wherein: the detection mechanism further comprises at least one diameter shooting device and at least one parallel backlight source;
the parallel backlight source and the diameter shooting device are oppositely arranged on two sides of the transmission line.
5. The vision-based bar defect inspection device of claim 4, wherein: the detection mechanism also comprises an industrial personal computer; the industrial personal computer is in communication connection with the defect shooting device so as to detect the defect of the first bar image shot by the defect shooting device; and the industrial personal computer is in communication connection with the diameter shooting device so as to measure the diameter of the second bar image shot by the diameter shooting device.
6. A vision-based bar defect inspection apparatus as defined in claim 5, wherein: the removing mechanism comprises an electric cylinder device and a fork arm; the electric cylinder device is arranged on one side of the transmission line; one surface of the fork arm, which is close to the transmission path, is an inclined surface, one surface of the fork arm, which is far away from the transmission path, is in contact with the end surface of the electric cylinder device, and the fork arm is arranged between the at least two transmission wheels and is lower than the transmission wheels in height;
the electric cylinder device is in communication connection with the industrial personal computer, and when receiving a rejection signal sent by the industrial personal computer, the electric cylinder device drives the fork arm to jack up the bar so that the bar rolls down along the fork arm.
7. A visual-based bar defect detection method, which is applied to the visual-based bar defect detection device of any one of claims 1-6, and is characterized in that: the method comprises the following steps:
step S1, rotating the driving wheel to transmit the bar stock;
step S2, shooting the bar stock to obtain a first bar stock image while transmitting the bar stock;
step S3, detecting defects of the bar stock according to the first bar stock image;
and step S4, if the defect of the bar stock is detected, removing the bar stock.
8. The vision-based bar defect detection method of claim 7, wherein: step S3 is a method of detecting defects of the bar according to the first bar image, including:
step S301, analyzing the first bar image to judge whether the bar has defects;
step S302, if the defect exists, the bar stock is positioned to determine a target area where the defect is located;
step S303, according to the target area, performing image segmentation on the first bar image to obtain a defect image;
step S304, extracting defect characteristics from the defect image; the defect characteristics at least comprise gray values, shapes and textures of the defect images;
and S305, classifying the bar stock according to the defect characteristics.
9. The vision-based bar defect detection method of claim 8, wherein: the following steps may be further included before step S301:
step S301a, performing distortion correction processing on the first bar stock image to obtain a corrected image;
step S301b, performing image enhancement processing on the corrected image to obtain a target image;
and step S301 is specifically: analyzing the target image to judge whether the bar stock has defects;
and step S303 specifically comprises: and according to the target area, carrying out image segmentation on the target image to obtain a defect image.
10. The vision-based bar defect detection method of claim 7, wherein: the following steps may also be included after step S2:
step S2a, shooting the bar stock to obtain a second bar stock image while transmitting the bar stock;
and step S2b, calculating the diameter of the bar stock according to the second bar stock image.
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