3D scanning for cylindrical secondary battery and appearance inspection device

Abstract

To provide a 3D scanning for a cylindrical secondary battery and an appearance inspection device which can rotate a cylindrical secondary battery and can conduct coordinate extraction and surface imaging for an appearance inspection to generate a 3D model at the same time.SOLUTION: The present disclosure makes it possible to simplify the configuration for 3D scanning and an appearance inspection of a cylindrical secondary battery, acquire accurate 3D data, and accurately inspect the appearance.SELECTED DRAWING: Figure 11

Description

Technical Field

[0001] The present invention relates to a 3D scanning and appearance inspection apparatus for a cylindrical secondary battery, and more particularly to an apparatus that can generate 3D data using 2D images and inspect the appearance.

Background Art

[0002] Techniques for scanning 3D data of an object are utilized in various industrial fields. In the case of a secondary battery, 3D scan data may be required for detecting physical deformations that occur during the manufacturing process.

[0003] Conventional 3D scan data has used methods such as time-of-flight cameras, stereo vision, laser scanning, and photogrammetry. Such methods have problems in that they take a long time and the accuracy decreases when performing 3D scanning on the curved surface of a cylindrical secondary battery.

Summary of the Invention

Problems to be Solved by the Invention

[0004] An object of the present invention is to provide an apparatus that can quickly and accurately 3D scan a cylindrical secondary battery and simultaneously inspect its appearance.

Means for Solving the Problems

[0005] As a means for solving the above problems, a mounting portion configured to be able to rotate an installed secondary battery about an axis in the longitudinal direction, a rear illumination portion configured to irradiate light toward the side surface of the secondary battery, a camera provided on the opposite side of the rear illumination portion with the secondary battery interposed therebetween, a control portion configured to control the mounting portion and the camera so as to be able to acquire an image of the secondary battery each time the secondary battery is rotated by a predetermined angle, and an arithmetic portion configured to extract the coordinates of the contour of the secondary battery from the image of the secondary battery and reconstruct a three-dimensional model. A 3D scanning apparatus for a cylindrical secondary battery is provided.

[0006] Here, the rear illumination unit is a back light for the secondary battery, and the camera may be configured to acquire a projection image of the secondary battery.

[0007] On the other hand, the arithmetic unit can receive information on a predetermined angle by which the secondary battery rotates from the control unit, and reconstruct a three-dimensional model based on the diameter of the secondary battery and the coordinates of the contour of the secondary battery by angle.

[0008] On the other hand, it further includes a drive unit configured to be able to rotate the secondary battery mounted on the mounting part around the longitudinal direction, and the control unit can control the drive unit to repeatedly adjust the angle of the mounting part by a predetermined angle up to a target angle of 360 degrees or less.

[0009] On the other hand, the arithmetic unit may be configured to extract boundary information from the contours of both side surfaces of the secondary battery from the image.

[0010] Further, the rear illumination unit may be configured to emit surface light.

[0011] On the other hand, the predetermined angle may be within 3 degrees.

[0012] On the other hand, it may further include a coaxial illumination unit configured to be able to irradiate light coaxially with the camera.

[0013] On the other hand, the arithmetic unit can extract first edge information close to the camera and second edge information farthest from the camera from the image to generate length information of the secondary battery.

[0014] Also, the arithmetic unit can extract interval information between the first edge information and the second edge information from the length information of the secondary battery, and correct the 3D model of the secondary battery based on the interval information.

[0015] Furthermore, a 3D scanning method for a cylindrical secondary battery is provided, including the steps of obtaining a projection image while irradiating light from the rear of the cylindrical secondary battery, the arithmetic unit extracting length information, outer diameter information, and side boundary information from the projection image, and the arithmetic unit generating a 3D model of the secondary battery based on the extracted length information, outer diameter information, and boundary information.

[0016] On the other hand, the step of obtaining the projection image can be obtained by taking a picture each time the secondary battery is adjusted to a predetermined angle.

[0017] On the other hand, the step of obtaining the projection image can be obtained by rotating the cylindrical secondary battery up to a target angle of 360 degrees or less around the axis in the length direction.

[0018] On the other hand, in the step of extracting information, two boundary informations due to the side surface of the secondary battery can be extracted from the projection image.

[0019] In addition, in the step of generating the 3D model, a part of the cylindrical secondary battery can be 3D modeled based on the boundary information extracted for each predetermined angle.

[0020] In addition, the step of obtaining the projection image can be performed together with light irradiation by surface emission behind the secondary battery.

[0021] On the other hand, the predetermined angle may be within 3 degrees.

[0022] On the other hand, the step of obtaining the projection image may be performed with additional irradiation of light coaxial with the camera.

[0023] On the other hand, the step of information extraction may further include the step of extracting the interval information between a first edge recognized by coaxial light and a second edge recognized by rear light on the upper and lower surfaces of the secondary battery from the projection image.

[0024] On the other hand, before the step of generating the three-dimensional model, a step of calculating the misaligned angle of the secondary battery based on the length information and the interval information may be further included.

[0025] Furthermore, a seating part configured to be rotatable about an axis in the length direction, a rear illumination part configured to irradiate light toward the side surface of the secondary battery, a camera provided on the side opposite to the rear illumination part with the secondary battery interposed therebetween, a front illumination part configured to irradiate light toward the side surface of the secondary battery, a control part configured to control the seating part and the camera to acquire an image of the secondary battery each time the secondary battery is rotated at a predetermined angle, and an arithmetic part configured to process the image acquired from the camera are included. The arithmetic part is configured to extract the coordinates of the contour of the secondary battery from the angle-specific images of the secondary battery to reconstruct a three-dimensional model, and to extract the surface area of the secondary battery from the angle-specific images of the secondary battery to generate an inspection image. A 3D scan and appearance inspection device for a cylindrical secondary battery can be provided.

[0026] On the other hand, the front illumination part may be configured to irradiate light at at least one different position along the length direction of the secondary battery.

[0027] Also, the control part may be configured to control the seating part and the camera to acquire a projection image each time the secondary battery rotates by a first angle, and to control the front illumination part and the camera to acquire a side image each time the secondary battery rotates by a second angle.

[0028] On the other hand, the first angle is characterized by being smaller than the second angle.

[0029] Also, the arithmetic part may be configured to crop and merge a partial area of the side surface of the secondary battery in a plurality of images acquired each time the secondary battery rotates by the second angle to generate a partial inspection image.

[0030] Further, the arithmetic unit may be configured to generate a complete side inspection image by combining partial inspection images for each second angle.

[0031] Furthermore, it may further include a defect detection unit configured to analyze the inspection image of the side surface of the secondary battery to detect appearance defects.

[0032] On the other hand, the arithmetic unit may be configured to extract the coordinates of the side boundary from the image and generate a three-dimensional model based on the angle of the secondary battery and the coordinates of the boundary.

[0033] Also, the arithmetic unit may be configured to extract the coordinates of the pixels where the boundary appears in order to extract the boundary coordinates of the side surface of the secondary battery from the image.

[0034] On the other hand, the control unit may set the first angle to be smaller than the second angle.

Advantages of the Invention

[0035] The 3D scanning and appearance inspection apparatus for a cylindrical secondary battery according to the present invention has the effect of maximizing the inspection efficiency by rotating the secondary battery and performing 3D scanning and appearance inspection simultaneously.

Brief Description of the Drawings

[0036]

Figure 1

Figure 2a

Figure 2b

Figure 3

Figure 4

Figure 5a

Figure 5b

Figure 5c

Figure 5d

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13a

Figure 13b

Figure 13c

Figure 14a

Figure 14b

Figure 14c

Figure 15

Figure 16

Embodiments for Carrying Out the Invention

[0037] Hereinafter, a 3D scanning device and a 3D scanning method for a cylindrical secondary battery according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the description of the following embodiments, the names of the respective components may be called by different names in the art. However, if there is functional similarity and identity, even if a modified embodiment is adopted, it can be regarded as an equivalent configuration. In addition, the reference numerals added to the respective components are described for convenience of explanation. However, the illustrated content on the drawings with these reference numerals does not limit the respective components within the scope of the drawings. Similarly, even if an embodiment in which a part of the configuration on the drawing is modified is adopted, if there is functional similarity and identity, it can be regarded as an equivalent configuration. Also, when it is recognized as a component that should be naturally included in view of the general technical level in the technical field, the description thereof will be omitted.

[0038] FIG. 1 is a perspective view of a 3D scanning device 1 for a cylindrical secondary battery 1000 according to a first embodiment of the present disclosure.

[0039] As shown in FIG. 1, the 3D scanning device 1 for the cylindrical secondary battery 1000 according to the first embodiment of the present disclosure may include a mounting portion 100, a driving portion (not shown), a rear illumination portion 200, a camera 300, a control portion (not shown), and a calculation portion (not shown).

[0040] The 3D scanning device 1 for the cylindrical secondary battery 1000 according to the first embodiment of the present disclosure is configured to acquire an image of the contour projected by the secondary battery 1000 while irradiating light from the rear of the secondary battery 1000.

[0041] The mounting portion 100 is configured to be able to mount the cylindrical secondary battery 1000 in a horizontal state. The mounting portion 100 may be configured to be disposed within the projection area by the secondary battery 1000 when the camera 300 takes a picture. That is, when the camera 300 takes a picture, the mounting portion 100 may be configured not to appear on the image.

[0042] The driving unit is configured to be able to rotate the cylindrical secondary battery 1000 mounted on the mounting portion 100 about the axis in the longitudinal direction. Here, the driving unit is configured to be able to repeatedly adjust the angle of the secondary battery 1000 to a predetermined angle. The driving unit may be configured to be able to rotate the secondary battery 1000 by 0.1 degrees to 3 degrees in one drive.

[0043] The rear illumination unit 200 and the camera 300 may be provided in opposite directions with respect to the mounting portion 100. The rear illumination unit 200 is configured to be able to irradiate light toward the secondary battery 1000 mounted on the mounting portion 100. The rear illumination unit 200 is configured to be able to emit surface light. That is, the rear illumination unit 200 can function as a back light for the secondary battery 1000.

[0044] The camera 300 is configured to be able to acquire an image projected while the light irradiated by the rear illumination unit 200 is blocked by the secondary battery 1000. The camera 300 is configured as an area camera 300 and can acquire a planar image.

[0045] On the other hand, although not shown, the 3D scanning device 1 for the cylindrical secondary battery 1000 according to the first embodiment of the present disclosure may further include a control unit and a calculation unit.

[0046] The control unit is configured to control the overall operation of the device. Specifically, it is configured to synchronize the operation of the rear lighting unit 200 and the operation of the camera 300. Also, it is configured to control the drive unit to adjust the angle of the secondary battery 1000. Therefore, the camera 300 is configured to acquire an image with the backlight activated each time the angle of the secondary battery 1000 changes.

[0047] The arithmetic unit is configured to extract the coordinates of the boundary from a plurality of images acquired from the camera 300 and perform 3D modeling. Dimensions of the secondary battery 1000 to be the object of 3D scanning can be input to the arithmetic unit in advance. That is, information regarding numerical values such as the outer diameter and length of the secondary battery 1000 is determined in advance at the manufacturing stage and can be input to the embodiments according to the present disclosure.

[0048] The arithmetic unit can perform modeling by deforming the scale for the coordinates confirmed from the image based on the information of the secondary battery 1000 input in advance.

[0049] Figures 2a and 2b are operation state diagrams of the first embodiment. In this figure, only the posture of the secondary battery 1000 and the rear lighting unit 200 are shown for convenience of explanation.

[0050] As shown in Figure 2a, in the first embodiment of the present disclosure, the rear lighting unit 200 is activated with the secondary battery 1000 stopped to acquire an image. At this time, an image of the projection of the secondary battery 1000 is acquired. What is confirmed from the projection image are the coordinates (P1, P2) of the point furthest away among the side surfaces composed of curved surfaces. Also, the boundary coordinates of the upper surface and the lower surface can be confirmed.

[0051] As shown in FIG. 2b, after rotating the secondary battery 1000 by a predetermined angle, the control unit activates the rear illumination unit 200 to acquire an image. At this time, when the secondary battery 1000 is projected, the coordinates obtained by being projected at the side boundary are coordinates separated at 180-degree intervals (P3, P4). The scanning device 1 according to the present disclosure repeats the processes shown in FIGS. 2a and 2b several times to several hundred times to rotate the secondary battery 1000 by 180 degrees. Since coordinates are extracted from both sides of the parallel boundary when the secondary battery 1000 rotates by 180 degrees, it becomes possible to extract the coordinates for the entire side surface of the secondary battery 1000 corresponding to 360 degrees.

[0052] FIG. 3 is a diagram showing an example of an image acquired in the first embodiment.

[0053] As shown in FIG. 3, when acquiring a projection image of the secondary battery 1000 with the backlight activated in the first embodiment, a simple image can be acquired. At this time, coordinates (PθR) can be extracted at the right boundary by the rotation angle (θ) extracted from the side boundary that appears on the upper side of FIG. 3. Also, coordinates (PθL) can be extracted at the left boundary.

[0054] FIG. 4 is an enlarged view showing an enlarged I region of FIG. 3.

[0055] As shown in FIG. 4, the arithmetic unit determines the coordinates of the boundary portion in the image acquired at the first angle (θ1) for each pixel. Looking at the region (I) enlarged at the first angle, the right boundary line can be confirmed for each pixel of the boundary. The x and y coordinates can be confirmed for each pixel. The arithmetic unit extracts the boundary coordinates in pixel units from the right boundary line and the left boundary line for each acquired image. Such a process of extracting the boundary coordinates by the arithmetic unit can be performed for each of a plurality of images.

[0056] As an example, when the control unit rotates the secondary battery 1000 one by one, the camera 300 can acquire 180 images. The calculation unit extracts the coordinates of the left and right boundaries from each of the 180 images.

[0057] FIGS. 5a, 5b, 5c and 5d are diagrams showing the concept of modeling using three-dimensional coordinates.

[0058] As shown in FIG. 5a, the calculation unit extracts the boundary coordinates at the first angle. When the extracted coordinates are displayed three-dimensionally, they can be shown as in FIG. 5a. At the first angle, the coordinates (P 1R (x, y)) extracted from the right boundary appear. Also, the coordinates extracted from the left boundary can appear in the three-dimensional space. At this time, the scale of the three-dimensional space can be adjusted and displayed according to the diameter of the secondary battery 1000 input in advance. The scale adjustment is performed by matching the rotation coordinate system corresponding to the radius (D / 2) from the rotation center of the secondary battery 1000 and the rotation angle with the extracted coordinates.

[0059] As shown in FIG. 5b, when the secondary battery 1000 is arranged at the second angle, the coordinates (P 1R (x, y), P 2R (x, y)) extracted from the right boundary appear in the three-dimensional space. Also, the coordinates extracted from the left boundary separated at 180-degree intervals appear in the three-dimensional space.

[0060] As shown in FIG. 5c, the processes described in FIGS. 5a and 5b are repeated to generate three-dimensional coordinates along the rotation angle. The coordinates (P 1R (x, y), P 2R (x, y), P 3R (x, y), P 4R (x, y)) extracted at the right boundary can be displayed at positions separated from the central axis by a predetermined angle (the rotation angle of the secondary battery 1000) respectively.

[0061] As shown in FIG. 5d, the arithmetic unit can rotate the secondary battery 1000 by 180 degrees and complete the coordinate extraction process to generate 3D data for 360 degrees.

[0062] As described above, in the present disclosure, the 3D scanning of the secondary battery 1000 can be performed by generating a 3D model using the coordinates extracted from the projection image. At this time, coordinates can be extracted from the images obtained using one camera 300, and 3D data merge can be executed for the extracted coordinates, so that the equipment can be simplified.

[0063] However, in this embodiment, an example of generating 3D data by rotating by 180 degrees has been described. However, it can also be implemented by modifying it to a method of generating 3D data by rotating the secondary battery 1000 by 360 degrees or more.

[0064] In addition, in this embodiment, an example of photographing one cylindrical battery has been described, but this is only an example, and the scanning device 1 according to the present disclosure can also be implemented by being modified to a method of simultaneously rotating and photographing various numbers of secondary batteries 1000 at the same time.

[0065] The arithmetic unit can perform appearance defect detection and the like using the generated 3D information of the secondary battery 1000.

[0066] Hereinafter, with reference to FIGS. 6 to 8, the 3D scanning device 1 for the cylindrical secondary battery 1000 according to the second embodiment of the present disclosure will be described. This embodiment may be configured to include the same components as the aforementioned first embodiment. For the same configuration, the description will be omitted so as not to be redundantly described, and different configurations will be described in detail.

[0067] When there is no coaxial illumination due to the cylindrical geometry, the image is acquired symmetrically, making it impossible to confirm in which direction the secondary battery 1000 is tilted. Also, the side coordinates can appear to have no difference on the projected image despite the tilt. Therefore, the second embodiment is configured to grasp the tilt of the secondary battery 1000 and generate and correct a 3D model based on this.

[0068] FIG. 6 is a perspective view of a 3D scanning apparatus 1 for a cylindrical secondary battery 1000 according to a second embodiment of the present disclosure.

[0069] As shown in FIG. 6, the 3D scanning apparatus 1 for a cylindrical secondary battery 1000 according to the second embodiment of the present disclosure may further include a mirror unit 500 and a coaxial illumination unit 400. The coaxial illumination unit 400 may be configured to include a beam splitter and an illumination module.

[0070] The mirror unit 500 is provided in the area photographed by the camera 300, and the camera 300 can acquire a projected image of the secondary battery 1000 reflected by the mirror unit 500.

[0071] The coaxial illumination unit 400 is configured to irradiate light onto the side surface of the secondary battery 1000 photographed by the camera 300.

[0072] The control unit is configured to be able to control the coaxial illumination unit 400, the rear illumination unit 200, the camera 300, and the drive unit. The control unit can control the camera 300 to acquire an image in a state where the coaxial illumination unit 400 and the rear illumination unit 200 irradiate light toward the secondary battery 1000 simultaneously.

[0073] In this embodiment, information on the boundary acquired by irradiating light from the rear of the secondary battery 1000 and the boundary of half of the side surface facing the camera 300 can be extracted. When the boundary coordinates of the front half and the rear half are different from each other, the calculation unit can calculate information on the deviation, and correct the three-dimensional model information based on the calculated deviation information.

[0074] However, although this embodiment shows a configuration in which the mirror unit 500 is added, it may also be implemented with the mirror unit omitted.

[0075] FIG. 7 is a diagram showing an example of an image obtained in the second embodiment.

[0076] As shown in FIG. 7, in the second embodiment, coaxial illumination can be used to check the boundary with respect to the front half surface (the surface facing the camera 300) of the secondary battery 1000.

[0077] Therefore, in this embodiment, light is irradiated using coaxial illumination to obtain an image. The calculation unit can extract the edge coordinates of the upper surface or the lower surface from the obtained image with respect to the surface facing the camera 300.

[0078] FIG. 8 is a diagram showing the concept of extracting coordinates from the I' region in FIG. 7 in order to compensate for misalignment in the second embodiment.

[0079] As shown in FIG. 8, the calculation unit extracts the coordinates (Pe1) of the first edge closest to the camera 300 among the coordinates confirmed by coaxial illumination. Also, the coordinates (Pe2) of the second edge farthest from the camera 300 among the coordinates confirmed by the rear illumination unit 200 are extracted. At this time, the coordinates closest or farthest from the camera 300 can be selected as the coordinates of the boundary intersecting the left - right central axis.

[0080] The calculation unit calculates how much it is tilted toward the camera 300 using the diameters of the upper and lower surfaces of the secondary battery 1000 and the distance between the first edge and the second edge input in advance. Based on this, the 3D data of the secondary battery 1000 described in the first embodiment is corrected based on the angle of the secondary battery 1000.

[0081] Hereinafter, with reference to FIG. 9, a 3D scanning method for a cylindrical secondary battery according to a third embodiment of the present disclosure will be described in detail.

[0082] FIG. 9 is a flowchart of a 3D scanning method for a cylindrical secondary battery according to a third embodiment of the present disclosure.

[0083] As shown in FIG. 9, the 3D scanning method for a cylindrical secondary battery according to the third embodiment of the present disclosure may include a step of obtaining a projection image while irradiating light from the rear of the cylindrical secondary battery (S110), a step of extracting length information, outer diameter information, and side boundary information from the projection image (S120), and a step of generating a three-dimensional model of the secondary battery (S130).

[0084] The step of obtaining a projection image while irradiating light from the rear of the cylindrical secondary battery (S110) is performed by irradiating light from the rear of the secondary battery and obtaining an image using a camera on the opposite side. This step is repeatedly performed while rotating the secondary battery by a predetermined angle. That is, by this step, dozens to hundreds of images of the secondary battery can be obtained.

[0085] The step of extracting length information, outer diameter information, and side boundary information from the projection image (S120) corresponds to a step of extracting boundary coordinates from the projected image and extracting length information, outer diameter information, and side boundary information of the secondary battery. The projection image can be obtained with the secondary battery fixed at the same position. Therefore, the size of the pixel confirmed from the image can be matched with the actual size based on a previously input reference value. Based on this, information regarding the length and outer diameter of the secondary battery can be extracted, and boundary information (two lines) for the side surface can be extracted.

[0086] The step of generating a three-dimensional model of the secondary battery (S130) corresponds to a step of performing three-dimensional modeling based on the extracted length information, outer diameter information, and side boundary information. In this step, since coordinates are extracted while rotating the cylindrical battery, the side boundary coordinates extracted for each predetermined angle are reconfigured three-dimensionally.

[0087] Hereinafter, a 3D scanning method for a cylindrical secondary battery according to a fourth embodiment of the present disclosure will be described with reference to FIG. 10.

[0088] Figure 10 is a flowchart of a 3D scanning method for a cylindrical secondary battery according to the fourth embodiment of the present disclosure.

[0089] In this embodiment, the projection image means an image obtained in a state where light is irradiated from the rear and at the same time from the front.

[0090] As shown in FIG. 10, the 3D scanning method for a cylindrical secondary battery according to the fourth embodiment of the present disclosure may include a step (S210) of obtaining a projection image in a state where light coaxial with the rear of the cylindrical secondary battery and the camera is irradiated, a step (S220) of extracting length information, outer diameter information, interval information, and side boundary information from the projection image, a step (S230) of calculating the misaligned angle of the secondary battery, and a step (S240) of generating a three-dimensional model. Here, the steps of extracting information and generating a three-dimensional model can be performed by an arithmetic unit including a processor.

[0091] The step (S210) of obtaining a projection image in a state where light coaxial with the rear of the cylindrical secondary battery and the camera is irradiated corresponds to a step of irradiating light from the front and rear of the secondary battery and obtaining an image.

[0092] The step (S220) of extracting length information, outer diameter information, interval information, and side boundary information from the projection image corresponds to a step of processing the image and extracting the coordinates of the pixels corresponding to the boundary. In this step, the edge of the upper surface or the lower surface that is irradiated with light from the front of the secondary battery and confirmed can be confirmed.

[0093] In particular, when the secondary battery is tilted with respect to the camera, the edge coordinates of the upper or lower surface that are confirmed when irradiated with light from the front and the edge coordinates of the upper or lower surface that are confirmed when irradiated with light from the rear can be confirmed simultaneously. At this time, the calculation unit can analyze the image to extract the coordinates of the edge that is actually the farthest from the camera and the coordinates of the edge that is the closest to the camera, and extract the interval information between these two coordinates. However, such interval coordinates may not be extracted when the secondary battery is correctly arranged and not displaced toward the camera, and the interval information can be zero.

[0094] The step of calculating the deviation angle of the secondary battery (S230) is a step of calculating how much the secondary battery is relatively displaced toward the camera using the outer diameter information and the interval information of the secondary battery.

[0095] The step of generating a 3D model (S240) corresponds to a step of correcting the 3D modeling of the side surface of the secondary battery based on the deviation angle of the secondary battery. With this step, even when the secondary battery is not positioned correctly toward the camera, the deviation angle can be easily grasped. Also, an accurate 3D modeling can be generated based on the deviation angle of the secondary battery.

[0096] As described above, the 3D scanning apparatus and 3D scanning method for a cylindrical secondary battery according to the present disclosure can reconstruct an accurate 3D model of the cylindrical secondary battery with a simple configuration including one camera.

[0097] Hereinafter, with reference to FIGS. 11 to 16, the 3D scanning and appearance inspection apparatus for a secondary battery according to the fifth embodiment of the present disclosure will be described in detail. Also in the following embodiments, the same components as those in the foregoing embodiments are included, and the description thereof will be omitted so as not to be duplicated, and different configurations will be described.

[0098] FIG. 11 is a perspective view of a 3D scanning and appearance inspection apparatus for a cylindrical secondary battery according to the fifth embodiment of the present disclosure, and FIG. 12 is a view showing a front illumination unit in the fifth embodiment of the present disclosure.

[0099] As shown in FIGS. 11 and 12, the 3D scanning and appearance inspection apparatus for a cylindrical secondary battery according to the fifth embodiment of the present disclosure includes a front lighting unit 600. The front lighting unit 600 may be configured to be coaxial with the camera and irradiate light toward the secondary battery. The front lighting unit 600 may include a beam splitter 620 and a front lighting module 610. The beam splitter may be provided at a point where the optical axes of the camera and the front lighting module 610 intersect.

[0100] The front lighting module 610 may include a plurality of lighting units 611, 612, ···, 618. The plurality of lighting units may be sequentially provided along the length direction of the secondary battery. Each lighting unit may be configured with a predetermined width. Also, each of the lighting units 611, 612, ···, 618 may be configured to be independently controlled by the control unit. However, although an example in which the front lighting module 610 is composed of eight lighting units is shown, this is merely an example and it may be configured with various numbers.

[0101] In the fifth embodiment of the present disclosure, the control unit can control the secondary battery to rotate at a predetermined angular interval. Each time the control unit rotates the secondary battery at a first angle, the control unit can control the camera to acquire a projection image for 3D scanning. Also, each time the control unit rotates the secondary battery 1000 at a second angle, the control unit can control the camera to acquire an image of the surface. The control unit may determine the first angle to be smaller than the second angle. That is, the images captured for 3D scanning can be controlled so that coordinates can be extracted more frequently for the generation of a precise 3D model.

[0102] The calculation unit can extract the boundary coordinates of the side surface of the secondary battery from the acquired projection image, and can generate a 3D model based on this. However, regarding the generation of such a 3D model by the calculation unit, the functions or methods described in the first to fourth embodiments above may be used.

[0103] However, although this embodiment shows a configuration in which the mirror unit 500 is added, it could also be implemented with the mirror unit omitted.

[0104] In this embodiment, the arithmetic unit can photograph the side surface of the secondary battery at different angles and combine them to generate an inspection image. Also, the appearance inspection unit can analyze the generated inspection image to detect defects on the side surface of the secondary battery. Examples of defects include scratches, dents, stains, foreign objects, and liquid leakage.

[0105] FIG. 13a, FIG. 13b, and FIG. 13c are diagrams showing the operating states of the front lighting unit in the fifth embodiment of the present disclosure, and FIG. 14a, FIG. 14b, and FIG. 14c are diagrams showing other operating states of the front lighting unit in the fifth embodiment of the present disclosure.

[0106] As shown in FIGS. 13a, 13b, and 13c, the front lighting module 610 is configured to include a plurality of lighting units, and each lighting unit is continuously provided along the length direction of the secondary battery. At this time, a predetermined area, for example, two adjacent lighting units may be controlled to be driven simultaneously. Two adjacent lighting units may be controlled in the order from FIG. 13a to FIG. 13b and then to FIG. 13c. That is, the first lighting unit 611 and the second lighting unit 612 operate first, and then the third lighting unit 613 and the fourth lighting unit 614 operate. And then, the fifth lighting unit 615 and the sixth lighting unit 616 can operate. Each time such a lighting operation position is phase-shifted, the camera can acquire an image.

[0107] As shown in FIGS. 14a, 14b, and 14c, the front lighting module can operate in various patterns and can be phase-shifted to operate. As shown in FIG. 14a, the first lighting unit 611 and the fifth lighting unit 615 can operate simultaneously. Subsequently, the second lighting unit 612 and the sixth lighting unit 616 operate simultaneously so that the operating lighting units are phase-shifted as shown in FIG. 14b. Subsequently, the third lighting unit 613 and the seventh lighting unit 617 can operate simultaneously as shown in FIG. 14c. Thus, each time the phase of the front lighting module is shifted, the camera can operate to acquire an image of the secondary battery.

[0108] However, the configuration of the front lighting module described with reference to FIGS. 13a to 14c is merely an example, and it may be configured with various numbers and various patterns. That is, it may be arranged in 1×N or arranged in N×M. In addition, the pattern in which the lighting unit operates can be deformed into various patterns capable of phase shift and operate.

[0109] FIG. 15 is a conceptual diagram showing the concept of generating a partial inspection image in the fifth embodiment of the present disclosure.

[0110] As shown in FIG. 15, the aforementioned front lighting module can circulate once when the secondary battery stops. Each time the operating position of the lighting unit is phase-shifted while circulating once, the camera can take a picture and acquire an image.

[0111] Therefore, the image of the secondary battery can be acquired by the number of phase shifts at a specific angle. For example, in FIG. 15, when the secondary battery is at the first angle, the first phase image (I1-1), the second phase image (I1-2), and the third phase image (I1-3) can be acquired.

[0112] The arithmetic unit crops and extracts a partial area that is taken most flatly from the three images. Here, the area taken flatly can be a partial area in the center on the image.

[0113] The calculation unit can generate a partial inspection image (i1) by combining the extracted partial regions. Since such a partial inspection image is generated based on the image obtained by phase-shifting the front illumination module, information regarding the partial height and low of the surface appears accurately. That is, when the calculation unit generates the partial inspection image (i1), an image in which depth information appears on a plane like 2.5D can be obtained.

[0114] On the other hand, although the generation process of the above-described partial inspection image has been described by taking as an example the generation based on three images obtained according to three illumination phases, this is merely an example, and the camera may be controlled so as to be able to obtain a plurality of images according to several to several tens of phases.

[0115] The control unit can execute the operation of such a front illumination unit and the operation of the camera each time the secondary battery is rotated to the second angle. Further, the calculation unit can generate a partial inspection image each time the secondary battery rotates at the second angle.

[0116] FIG. 16 is a conceptual diagram showing the concept of generating an inspection image in the fifth embodiment of the present disclosure.

[0117] As shown in FIG. 16, in this embodiment, the calculation unit can generate partial inspection images (I1, I2,..., In) for each second angle. Such a process is performed until the secondary battery rotates 360 degrees. The partial inspection image obtained at any one angle can be merged at a position adjacent to the partial inspection image at the next angle. Finally, the calculation unit can generate an inspection image (Iside) in which the side surface of the secondary battery appears completely.

[0118] On the other hand, although not shown, the defect detection unit can detect an appearance defect on the side surface of the secondary battery based on the inspection image.

[0119] However, in the above-described fifth embodiment, it was explained that the control unit rotates the secondary battery, acquires projection images at each first angle, extracts the contours, and acquires surface images at each second angle. At this time, at least one of the projection image and the surface image can be acquired depending on the sizes of the first angle and the second angle. That is, in some cases, only the projection image may be acquired when the secondary battery is at a specific angle, and only the surface image may be acquired at other angles. Also, in some cases, the projection image and the surface image of the secondary battery may be acquired simultaneously.

[0120] As described above, the 3D scanning and appearance inspection apparatus for a cylindrical secondary battery according to the present disclosure has an effect of maximizing the inspection efficiency by rotating the secondary battery and performing 3D scanning and appearance inspection simultaneously.

Description of Reference Numerals

[0121] 1: 3D Scanning Apparatus for Cylindrical Secondary Battery 100: Mounting Portion 200: Rear Lighting Unit 300: Camera 400: Coaxial Lighting Unit 500: Mirror Unit 600: Front Lighting Unit 1000: Secondary Battery

Claims

1. A mounting portion configured such that a mounted secondary battery can be rotated about an axis in the longitudinal direction; A rear illumination unit configured to irradiate light toward a side surface of the secondary battery; A camera provided on the opposite side of the rear illumination unit with the secondary battery interposed therebetween; A control unit configured to control the mounting portion and the camera so that an image of the secondary battery can be acquired each time the secondary battery is rotated by a predetermined angle; and A 3D scanning device for a cylindrical secondary battery including an arithmetic unit configured to extract coordinates of a contour of the secondary battery from an image of the secondary battery and reconstruct a 3D model.

2. The rear illumination unit is a backlight with respect to the secondary battery, The 3D scanning device for a cylindrical secondary battery according to claim 1, wherein the camera is configured to acquire a projection image of the secondary battery.

3. The arithmetic unit, Receives information on the predetermined angle by which the secondary battery rotates from the control unit, The 3D scanning device for a cylindrical secondary battery according to claim 2, wherein the 3D model is reconstructed based on a diameter of the secondary battery and coordinates of the contour at each angle of the secondary battery.

4. Further includes a drive unit configured to rotate the secondary battery mounted on the mounting portion about the longitudinal direction, The control unit, The 3D scanning device for a cylindrical secondary battery according to claim 3, wherein the drive unit is controlled to repeatedly adjust the angle of the mounting portion by the predetermined angle up to a target angle of 360 degrees or less.

5. The arithmetic unit, The 3D scanning device for a cylindrical secondary battery according to claim 4, wherein boundary information is extracted from contours of both side surfaces of the secondary battery from the image.

6. The 3D scanning device for a cylindrical secondary battery according to claim 5, wherein the rear illumination unit is configured to emit surface light.

7. The 3D scanning device for a cylindrical secondary battery according to claim 6, wherein the predetermined angle is within 3 degrees.

8. The 3D scanning device for a cylindrical secondary battery according to claim 1, further including a coaxial illumination unit configured to irradiate light coaxially with the camera.

9. The arithmetic unit, The 3D scanning device for a cylindrical secondary battery according to claim 8, which extracts first edge information closer to the camera from the image and second edge information farthest from the camera, and generates length information of the secondary battery.

10. The calculation unit extracts interval information between the first edge information and the second edge information as the length information of the secondary battery, and corrects the 3D model of the secondary battery based on the interval information. The 3D scanning device for a cylindrical secondary battery according to claim 9.

11. A mounting part configured such that the mounted secondary battery can be rotated about an axis in the length direction; A rear illumination part configured to irradiate light toward the side surface of the secondary battery; A camera provided on the opposite side of the rear illumination part with the secondary battery interposed therebetween; A front illumination part configured to irradiate light toward the side surface of the secondary battery; A control unit configured to control the mounting part and the camera to acquire an image of the secondary battery each time the secondary battery is rotated by a predetermined angle; and An arithmetic unit configured to process the image acquired from the camera, The arithmetic unit extracts coordinates of the contour of the secondary battery from the image of the secondary battery by angle, and is configured to be able to reconstruct a three-dimensional model, and a 3D scan and appearance inspection device for a cylindrical secondary battery configured to extract a surface area of the secondary battery from the image of the secondary battery by angle and generate an inspection image.

12. The front illumination part is configured to be able to irradiate light from at least one different position along the length direction of the secondary battery. The 3D scan and appearance inspection device for a cylindrical secondary battery according to claim 11.

13. The control unit is configured to control the mounting part and the camera to acquire a projection image each time the secondary battery rotates at a first angle, and is configured to control the front illumination part and the camera to be able to acquire a side image each time the secondary battery rotates at a second angle. The 3D scan and appearance inspection device for a cylindrical secondary battery according to claim 12.

14. The 3D scan and appearance inspection device for a cylindrical secondary battery according to claim 13, wherein the first angle is smaller than the second angle.

15. The arithmetic unit The 3D scan and appearance inspection apparatus for a cylindrical secondary battery according to claim 14, configured to crop and merge a partial area of the side surface of the secondary battery in a plurality of images acquired each time the secondary battery rotates at a second angle to generate a partial inspection image.

16. The arithmetic unit The 3D scan and appearance inspection apparatus for a cylindrical secondary battery according to claim 15, configured to combine the partial inspection images for each second angle to generate an inspection image of a complete side surface.

17. The 3D scan and appearance inspection apparatus for a cylindrical secondary battery according to claim 16, further including a defect detection unit configured to analyze an inspection image of the side surface of the secondary battery to detect an appearance defect.

18. The arithmetic unit extracts coordinates of the boundary of the side surface from the image, The 3D scan and appearance inspection apparatus for a cylindrical secondary battery according to claim 13, configured to generate a three-dimensional model based on the angle of the secondary battery and the coordinates of the boundary.

19. The arithmetic unit The 3D scan and appearance inspection apparatus for a cylindrical secondary battery according to claim 18, configured to extract coordinates of pixels where the boundary appears in order to extract boundary coordinates of the side surface of the secondary battery from the image.

20. The control unit sets the first angle to be smaller than the second angle in the 3D scan and appearance inspection apparatus for a cylindrical secondary battery according to claim 13.

Images