Visual inspection method in battery production line, and battery production line

Abstract

The present disclosure provides a visual inspection method in a battery production line, and a battery production line. The visual inspection method in a battery production line comprises: a control device controls an image acquisition device to perform image acquisition on a battery product to be inspected at a current working position, so as to obtain an image to be identified; a visual inspection device determines a current field of view size of the image acquisition device on the basis of said image, and determines a field of view difference value between the current field of view size and a reference field of view size; when the field of view difference value does not meet a preset field of view condition, the visual inspection device determines a target working position of the image acquisition device on the basis of the reference field of view size and the angle of view of the image acquisition device, and sends the target working position to the control device; and the control device controls the image acquisition device to move to the target working position.

Description

Visual inspection method in battery production line and battery production line

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure is based on Chinese patent application number 202410171594.6, application date February 6, 2024, and invention name “Visual inspection method in battery production line and battery production line”, and claims the priority of the Chinese patent application. The entire content of the Chinese patent application is hereby introduced into this disclosure as a reference. Technical Field

[0003] The present disclosure relates to, but is not limited to, the field of battery technology, and in particular to a visual inspection method in a battery production line and a battery production line. Background Art

[0004] New energy batteries are being used more and more widely in life and industry. For example, new energy vehicles equipped with batteries have been widely used. In addition, batteries are also being increasingly used in energy storage fields.

[0005] In battery production lines, visual inspection can be used to check the appearance and defects of battery products, facilitating production quality control. However, in related technologies, the field of view adjustment of image acquisition equipment lacks quantifiable data and typically requires manual adjustment based on experience, making consistency control difficult and thus impacting the stability of the image acquisition equipment's imaging results.

[0006] Summary of the Invention

[0007] In view of this, the embodiments of the present disclosure provide at least a visual inspection method and a battery production line in a battery production line, which can perform consistency control on the field of view size of the image acquisition device in the battery production line, realize automatic deviation correction of the working position of the image acquisition device, so as to improve the consistency of the field of view size of the image captured by the image acquisition device, thereby improving the stability of the imaging effect of the image acquisition device and reducing the error of the detection data.

[0008] The technical solution of the embodiment of the present disclosure is implemented as follows:

[0009] The present disclosure provides a visual inspection method for a battery production line. The battery production line includes a control device and a visual inspection system. The visual inspection system includes an image acquisition device and a visual inspection device. The visual inspection method includes:

[0010] The control device controls the image acquisition device to acquire an image of the battery product to be inspected at the current working position to obtain an image to be identified;

[0011] The visual inspection device determines the current field of view size of the image acquisition device based on the image to be identified, and determines the field of view difference between the current field of view size and the reference field of view size;

[0012] When the visual field difference does not meet the preset visual field condition, the visual inspection device determines the target working position of the image acquisition device based on the reference visual field size and the field of view angle of the image acquisition device, and sends the target working position to the control device;

[0013] The control device controls the image acquisition device to move to the target working position.

[0014] In the visual inspection method in the battery production line of the embodiment of the present disclosure, the control device controls the image acquisition device to capture an image of the battery product to be inspected at the current working position to obtain an image to be identified; the visual inspection device determines the current field of view size of the image acquisition device based on the image to be identified, and determines the field of view difference between the current field of view size and the reference field of view size; when the field of view difference does not meet the preset field of view condition, the visual inspection device determines the target working position of the image acquisition device based on the reference field of view size and the field of view angle of the image acquisition device, and sends the target working position to the control device; the control device controls the image acquisition device to move to the target working position. In this way, the field of view size of the image acquisition device in the battery production line can be controlled for consistency, and the automatic correction of the working position of the image acquisition device can be achieved to improve the consistency of the field of view size of the image captured by the image acquisition device, thereby improving the stability of the imaging effect of the image acquisition device and reducing the error of the detection data. In addition, since the image acquisition device can perform automatic correction of the working position, the workload of manual debugging of the image acquisition device can be reduced, and the deployment cycle of the image acquisition device can be shortened.

[0015] In some embodiments, the battery production line also includes an inspection machine, and the battery product to be inspected is placed on the inspection machine; the method also includes: the visual inspection equipment determines the reference field of view size based on the machine type of the inspection machine.

[0016] In this way, for the same type of detection machines, the same reference field of view size can be used for management and control, thereby improving the field of view consistency of the image acquisition device when acquiring images for the same type of detection machines.

[0017] In some embodiments, based on the image to be identified, determining the current field of view size of the image acquisition device includes: determining the mapping relationship between the image coordinate system where the image to be identified is located and the physical coordinate system; based on the image size of the image to be identified and the mapping relationship, determining the current field of view size of the image to be identified.

[0018] In this way, the current field of view size of the image to be recognized can be determined quickly and accurately according to the image size of the image to be recognized and the mapping relationship between the image coordinate system where the image to be recognized is located and the physical coordinate system.

[0019] In some embodiments, the current field of view size includes the diagonal length of the current field of view of the image acquisition device; based on the image size and mapping relationship of the image to be identified, the current field of view size of the image to be identified is determined, including: based on the image size, determining the image coordinates corresponding to the two diagonal points of the image to be identified; based on the mapping relationship and the image coordinates corresponding to the two diagonal points, determining the physical coordinates corresponding to the two diagonal points; based on the physical coordinates corresponding to the two diagonal points, determining the diagonal length of the current field of view of the image acquisition device.

[0020] In this way, since the diagonal length can comprehensively reflect the field of view of the image acquisition device in the width direction and the field of view in the length direction, the stability and comprehensiveness of the field of view size control can be improved by controlling the diagonal length of the current field of view of the image acquisition device.

[0021] In some embodiments, the preset field of view condition includes a size difference threshold, and the image acquisition device has a target distance between the target working position and the battery product; when the field of view difference value does not meet the preset field of view condition, the target working position of the image acquisition device is determined based on the reference field of view size and the field of view angle of the image acquisition device, including: when the field of view difference value exceeds the size difference threshold, the target distance is determined based on the reference field of view size and the field of view angle; and the target working position is determined based on the target distance.

[0022] In this way, when the field of view difference between the current field of view size of the image acquisition device and the reference field of view size exceeds the size difference threshold, the working position of the image acquisition device can be adjusted in time based on the reference field of view size and the field of view angle, so that there is a corresponding target distance between the image acquisition device and the battery product.

[0023] In some embodiments, the current field of view size includes the diagonal length of the current field of view of the image acquisition device; before determining the target working position of the image acquisition device based on the reference field of view size and the field of view angle of the image acquisition device, the method also includes: obtaining the diagonal length of the image sensor in the image acquisition device and the focal length of the lens of the image acquisition device; and determining the field of view angle based on the diagonal length and the focal length of the lens.

[0024] In this way, the field of view angle of the image acquisition device can be determined quickly and accurately.

[0025] In some embodiments, the visual detection system also includes a light source controller; the method also includes: the visual detection device locates the area to be detected from the image to be identified; the visual detection device determines the image grayscale information within the area to be detected; when the image grayscale information does not meet the preset grayscale conditions, the visual detection device sends a brightness adjustment instruction to the light source controller; the light source controller adjusts the brightness of the light source in the visual detection system in response to the brightness adjustment instruction.

[0026] In this way, when the grayscale information of the image does not meet the preset grayscale conditions, the visual inspection device sends a brightness adjustment instruction to the light source controller to adjust the brightness of the light source in the visual inspection system. This can achieve self-adaptation of the light source brightness in the visual inspection scene, so as to improve the consistency of the grayscale information of the image captured by the image acquisition device, thereby further improving the stability of the imaging effect of the image acquisition device and reducing the error of the detection data.

[0027] In some embodiments, the image grayscale information includes the average grayscale value of each pixel in the area to be detected; when the image grayscale information does not meet the preset grayscale conditions, the visual detection device sends a brightness adjustment instruction to the light source controller, including: when the average grayscale value exceeds the preset average range, the visual detection device sends a brightness adjustment instruction to the light source controller.

[0028] In this way, the grayscale information consistency of the image captured by the image acquisition device can be further improved by controlling the grayscale value mean of each pixel in the detection area.

[0029] In some embodiments, the image grayscale information also includes the grayscale value range of each pixel in the area to be detected; the method also includes: the visual inspection device outputs a first prompt information when the grayscale value range exceeds the range threshold.

[0030] In this way, due to the presence of foreign objects blocking or reflecting light in battery products, lenses or light sources, the grayscale values ​​of each pixel in the area to be inspected may differ too much. Therefore, when the extreme difference of the grayscale values ​​of each pixel in the area to be inspected exceeds the extreme difference threshold, the visual inspection equipment outputs a first prompt message, which can remind the operator to check for abnormalities in time, improve the stability of the imaging effect of the image acquisition equipment, and reduce the over-kill rate of visual inspection.

[0031] In some embodiments, the method further includes: the visual detection device records the number of times the brightness of the light source in the visual detection system is continuously adjusted; and the visual detection device outputs a second prompt message when the number exceeds a threshold.

[0032] In this way, when the number of times the brightness of the light source in the visual inspection system is continuously adjusted exceeds the threshold, the second prompt information is output to remind the operator to detect the light source abnormality in time and reduce the problem of poor imaging effect of the image acquisition equipment due to the light source abnormality.

[0033] An embodiment of the present disclosure provides a battery production line, comprising:

[0034] Control equipment and visual inspection system, the visual inspection system includes image acquisition equipment and visual inspection equipment; wherein:

[0035] A control device, used to control the image acquisition device to move to a current working position, and control the image acquisition device to acquire an image of the battery product to be inspected at the current working position to obtain an image to be identified;

[0036] A visual detection device, configured to determine a current field of view size of an image acquisition device based on an image to be recognized, and to determine a field of view difference between the current field of view size and a reference field of view size;

[0037] a visual detection device, configured to determine a target working position of the image acquisition device based on a reference field of view size and a field of view angle of the image acquisition device when the field of view difference does not satisfy a preset field of view condition, and transmit the target working position to the control device;

[0038] The control device is used to control the image acquisition device to move to the target working position.

[0039] In the battery production line of the embodiment of the present disclosure, the control device controls the image acquisition device to capture images of the battery product to be inspected at the current working position to obtain the image to be identified; the visual inspection device determines the current field of view size of the image acquisition device based on the image to be identified, and determines the field of view difference between the current field of view size and the reference field of view size; when the field of view difference does not meet the preset field of view condition, the visual inspection device determines the target working position of the image acquisition device based on the reference field of view size and the field of view angle of the image acquisition device, and sends the target working position to the control device; the control device controls the image acquisition device to move to the target working position. In this way, the field of view size of the image acquisition device in the battery production line can be consistently controlled, and the automatic deviation correction of the working position of the image acquisition device can be realized to improve the consistency of the field of view size of the image captured by the image acquisition device, thereby improving the stability of the imaging effect of the image acquisition device and reducing the error of the detection data. In addition, since the image acquisition device can automatically correct the working position, the workload of manual debugging of the image acquisition device can be reduced, and the deployment cycle of the image acquisition device can be shortened.

[0040] In some embodiments, the battery production line also includes an inspection machine, on which the battery products to be inspected are placed; and a visual inspection device for determining a reference field of view size based on the machine type of the inspection machine.

[0041] In this way, for the same type of detection machines, the same reference field of view size can be used for management and control, thereby improving the field of view consistency of the image acquisition device when acquiring images for the same type of detection machines.

[0042] In some embodiments, the visual detection device is used to: determine the mapping relationship between the image coordinate system of the image to be identified and the physical coordinate system; and determine the current field of view size of the image to be identified based on the image size of the image to be identified and the mapping relationship.

[0043] In this way, the current field of view size of the image to be recognized can be determined quickly and accurately according to the image size of the image to be recognized and the mapping relationship between the image coordinate system where the image to be recognized is located and the physical coordinate system.

[0044] In some embodiments, the visual detection system also includes a light source controller; a visual detection device, used to: locate the area to be detected from the image to be identified, and determine the image grayscale information within the area to be detected; when the image grayscale information does not meet the preset grayscale conditions, send a brightness adjustment instruction to the light source controller; the light source controller, used to adjust the brightness of the light source in the visual detection system in response to the brightness adjustment instruction.

[0045] In this way, when the grayscale information of the image does not meet the preset grayscale conditions, the visual inspection device sends a brightness adjustment instruction to the light source controller to adjust the brightness of the light source in the visual inspection system. This can achieve self-adaptation of the light source brightness in the visual inspection scene, so as to improve the consistency of the grayscale information of the image captured by the image acquisition device, thereby further improving the stability of the imaging effect of the image acquisition device and reducing the error of the detection data.

[0046] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and are not intended to limit the technical solutions of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The accompanying drawings herein are incorporated into and constitute a part of the specification. These drawings illustrate embodiments consistent with the present disclosure and, together with the specification, are used to explain the technical solutions of the present disclosure.

[0048] FIG1 is a schematic diagram of the structure of a battery production line according to an embodiment of the present disclosure;

[0049] FIG2 is a schematic diagram of an implementation flow of a visual inspection method in a battery production line provided by an embodiment of the present disclosure;

[0050] FIG3 is a second schematic diagram of the structure of a battery production line provided by an embodiment of the present disclosure;

[0051] FIG4 is a schematic diagram of image coordinates of corner points of an image to be identified in a visual inspection method in a battery production line provided by an embodiment of the present disclosure;

[0052] FIG5 is a schematic diagram of the physical coordinates corresponding to the corner points of an image to be identified in a visual inspection method in a battery production line provided by an embodiment of the present disclosure;

[0053] FIG6 is a schematic diagram of the imaging principle of an image acquisition device provided by an embodiment of the present disclosure;

[0054] FIG7 is a third schematic diagram of the structure of a battery production line provided by an embodiment of the present disclosure;

[0055] FIG8 is a schematic diagram of an application scenario of a visual inspection method in a battery production line provided by an embodiment of the present disclosure;

[0056] FIG9 is a schematic diagram of a field of view consistency control process provided by an embodiment of the present disclosure;

[0057] FIG10 is a schematic diagram of a light source adaptive control process provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0058] In order to make the purpose, technical solutions and advantages of the present disclosure clearer, the technical solutions of the present disclosure are further elaborated in detail below with reference to the accompanying drawings and embodiments. The described embodiments should not be regarded as limiting the present disclosure. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present disclosure.

[0059] In the following description, reference is made to “some embodiments”, which describes a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0060] The terms "first / second / third" involved are merely used to distinguish similar objects and do not represent a specific ordering of the objects. It is understandable that "first / second / third" can be interchanged with a specific order or sequence where permitted so that the embodiments of the present disclosure described herein can be implemented in an order other than that illustrated or described herein.

[0061] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present disclosure pertains. The terms used herein are for the purpose of describing the present disclosure only and are not intended to limit the present disclosure.

[0062] Currently, new energy batteries are increasingly being used in everyday life and industry. New energy batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power stations, but are also widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric vehicles, as well as in a variety of fields such as aerospace. As the application areas of power batteries continue to expand, their market demand is also growing. In the embodiments of the present disclosure, the battery can be a single battery cell. A battery cell refers to a basic unit that can convert chemical energy into electrical energy and can be used to make a battery module or battery pack to power electrical devices. A battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active material after discharge and continue to be used. The battery cell can be a lithium-ion battery, a sodium-ion battery, a sodium-lithium-ion battery, a lithium metal battery, a sodium metal battery, a lithium-sulfur battery, a magnesium-ion battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lead-acid battery, etc., but the embodiments of the present disclosure are not limited to this. In the embodiments of the present disclosure, the battery can also be a single physical module comprising one or more battery cells to provide higher voltage and capacity. When there are multiple battery cells, the multiple battery cells are connected in series, in parallel, or in parallel via a busbar.

[0063] The battery product in the embodiments of the present disclosure may include multiple battery cells, each of which may have a positive electrode column and a negative electrode column. For example, a battery cell may be a battery cell. In some embodiments, the battery product may be a battery module (Module) composed of multiple battery cells. For example, the battery module may be a new energy power battery module. In some embodiments, the battery product may be a battery pack (Pack) composed of multiple battery cells or battery modules. For example, the battery pack may be a new energy power battery pack.

[0064] In related technologies, the battery charging method uses a low current for trickle charging when the battery voltage is low, followed by a higher current for constant current charging until the battery reaches a predetermined voltage, and then a constant voltage charging method at the end of the charging period. While this method is easy to implement, it does not provide a reasonable plan for the charging current. If the charging current is not properly controlled, it can lead to irreversible degradation of the battery capacity, thereby shortening the battery life.

[0065] In order to better understand the visual inspection method in the battery production line provided by the embodiment of the present disclosure, the battery production line provided by the embodiment of the present disclosure is first described below.

[0066] FIG1 is a schematic diagram of the structure of a battery production line according to an embodiment of the present disclosure. As shown in FIG1 , the battery production line 100 according to an embodiment of the present disclosure includes a control device 110 and a visual inspection system 120 , wherein the visual inspection system 120 includes an image acquisition device 121 and a visual inspection device 122 .

[0067] The control device 110 can be used to control the operation of various mechanisms in the battery production line. In practice, the control device 110 can be, for example, an industrial computer or a programmable logic controller (PLC). For example, the control device 110 can be a PLC used to control the operation of various mechanisms in a visual inspection station.

[0068] The image acquisition device 121 may include, but is not limited to, at least one of a two-dimensional camera, a three-dimensional camera, a depth camera, a line scan camera, an area scan camera, etc. For example, the image acquisition device 121 may include a charge coupled device (CCD) camera.

[0069] Visual inspection device 122 may be an electronic computing device with logical operation capabilities, including but not limited to a server or industrial computer. Visual inspection device 122 may establish a wired or wireless communication connection with image acquisition device 121 to receive the image to be recognized captured by image acquisition device 121 and perform visual inspection of the appearance and / or defects of the battery product in the image to be recognized.

[0070] Based on the battery production line provided by the above-mentioned embodiment of the present disclosure, the embodiment of the present disclosure provides a visual inspection method in a battery production line, which can control the consistency of the field of view size of the image acquisition device in the battery production line, realize automatic deviation correction of the working position of the image acquisition device, and improve the consistency of the field of view size of the image captured by the image acquisition device, thereby improving the stability of the imaging effect of the image acquisition device and reducing the error of the detection data. Figure 2 is a schematic diagram of the implementation process of a visual inspection method in a battery production line provided by the embodiment of the present disclosure. As shown in Figure 2, the method includes the following steps S101 to S104:

[0071] Step S101: The control device controls the image acquisition device to acquire an image of a battery product to be inspected at a current working position to obtain an image to be identified.

[0072] Here, the current working position refers to the current position of the image acquisition device.

[0073] The control device may control the image acquisition device to arrive at the current working position in advance, and then control the image acquisition device to acquire images of the battery product to be inspected at the current working position.

[0074] In some embodiments, a battery production line may include a testing machine, on which a battery product to be tested may be placed. A drive assembly capable of moving up and down may be provided above the testing machine, and an image capture device may be fixedly connected to the drive assembly. A control device may drive the image capture device to move up and down by controlling the drive assembly to move up and down, so that the image capture device reaches its current working position. In response to the image capture device reaching its current working position, the control device may send an image capture instruction to the image capture device, and the image capture device may capture an image of the battery product to be tested in response to the image capture instruction to obtain an image to be recognized.

[0075] In step S102 , the visual inspection device determines the current field of view size of the image acquisition device based on the image to be recognized, and determines the field of view difference between the current field of view size and the reference field of view size.

[0076] Here, the current field of view size of the image acquisition device may include but is not limited to any suitable key size of the current field of view of the image acquisition device. For example, the current field of view size may include but is not limited to the width, length and / or diagonal length of the current field of view of the image acquisition device.

[0077] During implementation, those skilled in the art may determine the current field of view of the image acquisition device based on the image to be identified in any appropriate manner according to actual circumstances, and the embodiments of the present disclosure are not limited thereto.

[0078] In some embodiments, the pixel count and image size of the image to be identified can be obtained. Based on the pixel count and image resolution, the current field of view of the image acquisition device can be obtained. The pixel count of the image to be identified refers to the physical size of a single pixel in the image to be identified. During implementation, the pixel count of the image to be identified can be determined based on the image size and resolution of the image to be identified, and the image size corresponding to a single pixel in the image to be identified can be obtained. This image size corresponding to a single pixel can then be converted to the pixel count of the image to be identified based on the camera calibration matrix. For example, if the current field of view size includes the width of the current field of view of the image acquisition device, the width of the current field of view of the image acquisition device can be determined as the product of the pixel count of the image to be identified and the number of pixels contained in the image to be identified in the horizontal direction. For another example, if the current field of view size includes the length of the current field of view of the image acquisition device, the length of the current field of view of the image acquisition device can be determined as the product of the pixel count of the image to be identified and the number of pixels contained in the image to be identified in the vertical direction. For another example, when the current field of view size includes the diagonal length of the current field of view of the image acquisition device, the width and length of the current field of view of the image acquisition device can be determined first, and then the diagonal length can be determined based on the width and length.

[0079] In some embodiments, a mapping relationship between the image coordinate system of the image to be recognized and the physical coordinate system can be determined, and based on this mapping relationship, the image size of the image to be recognized can be converted to the current field of view size of the image acquisition device. The image size may include, but is not limited to, image width, image height, and / or image diagonal length.

[0080] The reference field of view size is predetermined based on actual inspection requirements and is not limited in the presently disclosed embodiments. It is understood that because the distance between the image acquisition device and the battery product to be inspected affects the field of view size of the image acquisition device, when the field of view size of the image acquisition device is the reference field of view size, a preset reference distance exists between the image acquisition device and the battery product, ensuring that the image to be identified obtained by the image acquisition device from the battery product can meet actual inspection requirements.

[0081] Step S103 , when the field of view difference does not meet the preset field of view condition, the visual inspection device determines the target working position of the image acquisition device based on the reference field of view size and the field of view angle of the image acquisition device, and sends the target working position to the control device.

[0082] Here, the preset field of view condition may be pre-set by those skilled in the art according to actual conditions, and the embodiments of the present disclosure are not limited thereto.

[0083] In some embodiments, the preset visual field condition may include a preset size difference threshold and / or size difference range. When the visual field difference value exceeds the size difference threshold or the visual field difference value exceeds the size difference range, it can be determined that the visual field difference value does not meet the preset visual field condition. During implementation, the size difference threshold and / or size difference range can be determined in advance based on visual detection requirements. For example, the size difference threshold can be 0.1 millimeter (mm). For another example, the size difference range can be (-0.1mm, 0.1mm).

[0084] The target working position refers to a working position in which the difference between the field of view of the image acquisition device and the reference field of view size satisfies a preset field of view condition. The disclosed embodiments do not limit the manner in which the target working position is determined based on the reference field of view size and the field of view angle of the image acquisition device. In some embodiments, the geometric relationship between the field of view size, field of view angle, and working position of the image acquisition device can be determined based on the imaging principle of the image acquisition device. This geometric relationship can then be used to perform geometric calculations based on the reference field of view size and field of view angle to obtain the target working position.

[0085] Step S104: The control device controls the image acquisition device to move to the target working position.

[0086] During implementation, the control device may control the movement of the image acquisition device in any appropriate manner, and the embodiments of the present disclosure are not limited thereto.

[0087] In some embodiments, after acquiring the target working position, the control device can drive the image acquisition device to move to the target working position by controlling a driving component fixedly connected to the image acquisition device to move in an up and down direction.

[0088] In the visual inspection method in the battery production line of the embodiment of the present disclosure, the control device controls the image acquisition device to capture an image of the battery product to be inspected at the current working position to obtain an image to be identified; the visual inspection device determines the current field of view size of the image acquisition device based on the image to be identified, and determines the field of view difference between the current field of view size and the reference field of view size; when the field of view difference does not meet the preset field of view condition, the visual inspection device determines the target working position of the image acquisition device based on the reference field of view size and the field of view angle of the image acquisition device, and sends the target working position to the control device; the control device controls the image acquisition device to move to the target working position. In this way, the field of view size of the image acquisition device in the battery production line can be controlled for consistency, and the automatic correction of the working position of the image acquisition device can be achieved to improve the consistency of the field of view size of the image captured by the image acquisition device, thereby improving the stability of the imaging effect of the image acquisition device and reducing the error of the detection data. In addition, since the image acquisition device can perform automatic correction of the working position, the workload of manual debugging of the image acquisition device can be reduced, and the deployment cycle of the image acquisition device can be shortened.

[0089] In some embodiments, referring to FIG3 , the battery production line 100 further includes a testing machine 130 , and the battery product to be tested is placed on the testing machine 130 . The visual inspection method in the battery production line further includes the following step S111 :

[0090] In step S111 , the visual inspection device determines a reference field of view size based on the type of the inspection machine.

[0091] Here, the machine type may include but is not limited to at least one of the model of the detection machine, the type of detection task performed by the detection machine, and the like.

[0092] In this way, for the same type of detection machines, the same reference field of view size can be used for management and control, thereby improving the field of view consistency of the image acquisition device when acquiring images for the same type of detection machines.

[0093] In some embodiments, the machine type includes the model of the inspection machine. Since inspection machines of the same model generally require a consistent visual inspection field of view, corresponding reference field of view sizes can be set for different inspection machine models. During implementation, determining a reference field of view size corresponding to each inspection machine model can improve the field of view consistency of the image acquisition device when capturing images from the same inspection machine model.

[0094] In some embodiments, the machine type includes the type of inspection task performed by the inspection machine. Since inspection machines performing the same inspection task type generally require consistent visual inspection fields of view, corresponding reference field of view sizes can be set for different inspection task types. During implementation, determining a reference field of view size corresponding to each inspection machine model based on the inspection task type performed by that machine can improve field of view consistency when image acquisition devices capture images from inspection machines performing the same inspection task type.

[0095] In some embodiments, determining the current field of view size of the image acquisition device based on the image to be recognized in step S102 may include the following steps S121 to S122:

[0096] Step S121 : determining a mapping relationship between the image coordinate system where the image to be recognized is located and the physical coordinate system.

[0097] In practice, the mapping relationship between the image coordinate system of the image to be recognized and the physical coordinate system can be obtained by calibrating the image acquisition device after presetting it in a standard working position. The standard working position can be a position where the field of view size of the image acquisition device is consistent with the reference field of view size.

[0098] In some embodiments, the mapping relationship may include a calibration matrix of the image acquisition device.

[0099] Step S122 : determining the current field of view size of the image to be recognized based on the image size of the image to be recognized and the mapping relationship.

[0100] Here, the current field of view size of the image to be identified may be determined in any appropriate manner based on the image size of the image to be identified and the mapping relationship, and the embodiments of the present disclosure are not limited thereto.

[0101] In some embodiments, the current field of view size of the image to be identified includes the width of the current field of view of the image acquisition device, and the image size includes the image width of the image to be identified in the horizontal direction; based on the image width, the image coordinates of the first starting point and the first end point of the wide side of the image to be identified in the image coordinate system can be determined; based on the mapping relationship, the image coordinates of the first starting point and the first end point in the image coordinate system can be converted into the physical coordinates corresponding to the first starting point and the first end point in the physical coordinate system; according to the physical coordinates corresponding to the first starting point and the first end point in the physical coordinate system, the distance between the first starting point and the first end point in the physical coordinate system can be determined, which is the width of the current field of view of the image acquisition device.

[0102] In some embodiments, the current field of view size of the image to be identified includes the length of the current field of view of the image acquisition device, and the image size includes the image height of the image to be identified in the vertical direction; based on the image height, the image coordinates of the second starting point and the second end point of the high side of the image to be identified in the image coordinate system can be determined; based on the mapping relationship, the image coordinates of the second starting point and the second end point in the image coordinate system can be converted into the physical coordinates corresponding to the second starting point and the second end point in the physical coordinate system; according to the physical coordinates corresponding to the second starting point and the second end point in the physical coordinate system, the distance between the second starting point and the second end point in the physical coordinate system can be determined, which is the length of the current field of view of the image acquisition device.

[0103] In some embodiments, the current field of view size of the image to be identified includes the diagonal length of the current field of view of the image acquisition device, and the image size includes the image width and image height of the image to be identified; based on the image width and image height, the image coordinates of the two diagonal points of the image to be identified in the image coordinate system can be determined; based on the mapping relationship, the image coordinates of the two diagonal points in the image coordinate system can be converted into the physical coordinates corresponding to the two diagonal points in the physical coordinate system; according to the physical coordinates corresponding to the two diagonal points in the physical coordinate system, the distance between the two diagonal points in the physical coordinate system can be determined, which is the diagonal length of the current field of view of the image acquisition device.

[0104] In this way, the current field of view size of the image to be recognized can be determined quickly and accurately according to the image size of the image to be recognized and the mapping relationship between the image coordinate system where the image to be recognized is located and the physical coordinate system.

[0105] In some embodiments, the current field of view size includes the diagonal length of the current field of view of the image acquisition device. The above step S122 may include the following steps S131 to S133:

[0106] Step S131 : determining the image coordinates corresponding to two diagonal points of the image to be identified based on the image size.

[0107] Step S132 : determining the physical coordinates corresponding to the two diagonal points based on the mapping relationship and the image coordinates corresponding to the two diagonal points.

[0108] Step S133: determining the diagonal length of the current field of view of the image acquisition device based on the physical coordinates corresponding to the two diagonal points.

[0109] It's understood that in the image coordinate system, the upper left corner of the image to be identified is the coordinate origin, and the width and height of the image to be identified are located on the horizontal and vertical axes of the image coordinate system, respectively. Therefore, after determining the image size of the image to be identified, the image coordinates of each corner point of the image to be identified can be determined based on this image size. The two diagonal points of the image to be identified refer to two opposite corner points in the image to be identified.

[0110] For example, referring to Figures 4 and 5 , the image width of image 210 to be identified is Image_Width, and the image height is Image_Height. Based on the image width and image height, the image coordinates of corner point A in image 210 to be identified can be determined to be (0, 0), the image coordinates of corner point B to be (Image_Width, 0), the image coordinates of corner point C to be (Image_Width, Image_Height), and the image coordinates of corner point D to be (0, Image_Height), where corner points A and C are diagonal points, and corner points B and D are also diagonal points. Based on the mapping relationship between the image coordinate system of the image to be identified and the physical coordinate system, the image coordinates of each corner point A, B, C, and D of image 210 to be identified in the image coordinate system can be converted into physical coordinates A'(x1, y1), B'(x2, y2), C'(x3, y3), and D'(x4, y4) in the physical coordinate system, respectively. 4 , the area enclosed by A', B', C', and D' is the image acquisition device's current field of view 220. By calculating the distance between A' and C', or the distance between B' and D', the diagonal length of the image acquisition device's current field of view can be obtained.

[0111] In this way, since the diagonal length can comprehensively reflect the field of view of the image acquisition device in the width direction and the field of view in the length direction, the stability and comprehensiveness of the field of view size control can be improved by controlling the diagonal length of the current field of view of the image acquisition device.

[0112] In some embodiments, the preset field of view condition includes a size difference threshold, and the image acquisition device has a target distance from the battery product at the target working position.

[0113] In the above step S103, when the field of view difference does not meet the preset field of view condition, determining the target working position of the image acquisition device based on the reference field of view size and the field of view angle of the image acquisition device may include the following steps S141 to S142:

[0114] Step S141 : When the field of view difference value exceeds the size difference threshold, the target distance is determined based on the reference field of view size and the field of view angle.

[0115] Step S142: determining a target working position based on the target distance.

[0116] During implementation, the geometric relationship between the field of view size, field of view angle and working position of the image acquisition device can be determined based on the imaging principle of the image acquisition device, and based on the geometric relationship, any appropriate method can be used to determine the target distance between the image acquisition device and the battery product based on the reference field of view size and the field of view angle of the image acquisition device.

[0117] Figure 6 is a schematic diagram of the imaging principle of an image acquisition device provided by an embodiment of the present disclosure. As shown in Figure 6, the half field of view angle of the image acquisition device is θ, the field of view angle is 2θ, the target distance is WD, and the reference field of view size of the image acquisition device is the reference diagonal length of the current field of view 2*FOV. Then, the target distance WD and half of the reference diagonal length FOV and the half field of view angle θ satisfy the geometric relationship shown in the following formula 1-1. Based on this geometric relationship, the target distance WD can be obtained: WD = (FOV / 2)*tan((180-θ) / 2) (1-1).

[0118] In this way, when the field of view difference between the current field of view size of the image acquisition device and the reference field of view size exceeds the size difference threshold, the working position of the image acquisition device can be adjusted in time based on the reference field of view size and the field of view angle, so that there is a corresponding target distance between the image acquisition device and the battery product.

[0119] In some embodiments, the current field of view size includes the diagonal length of the current field of view of the image acquisition device.

[0120] Before determining the target working position of the image acquisition device based on the reference field size and the field angle of the image acquisition device in step S103, the method may further include the following steps S151 to S152:

[0121] Step S151: Obtain the diagonal length of the image sensor in the image acquisition device and the focal length of the lens of the image acquisition device.

[0122] Step S152: determining the field of view angle based on the diagonal length and the focal length of the lens.

[0123] Here, the diagonal length of the image sensor and the focal length of the lens of the image acquisition device are inherent or pre-set parameters of the image acquisition device.

[0124] Continuing with Figure 6, the half-diagonal length of the image sensor in the image acquisition device is y, the diagonal length is 2y, the focal length of the lens of the image acquisition device is f, the half field of view angle is θ, and the field of view angle is 2θ. Then, the half-diagonal length y of the image sensor, the focal length f of the lens, and the half field of view angle θ satisfy the geometric relationship shown in the following formula 1-2. Based on this geometric relationship, the field of view angle 2θ of the image acquisition device can be obtained: θ = arctan(y / f) (1-2).

[0125] In this way, the field of view angle of the image acquisition device can be determined quickly and accurately.

[0126] In some embodiments, referring to FIG7 , the visual inspection system 120 further includes a light source controller 123. The above method may further include the following steps S161 to S164:

[0127] In step S161 , the visual inspection device locates the area to be inspected from the image to be identified.

[0128] Here, any appropriate region of interest positioning algorithm can be used according to actual detection requirements to locate the region to be detected from the image to be identified, and the embodiments of the present disclosure are not limited to this.

[0129] In some embodiments, the area to be inspected can be located by identifying marking points with fixed features in the battery product.

[0130] Step S162: The visual inspection device determines the grayscale information of the image in the area to be inspected.

[0131] Here, the image grayscale information may include, but is not limited to, at least one of the grayscale value of each pixel in the area to be detected, the grayscale value mean of each pixel, and the grayscale value range of each pixel. The grayscale value range refers to the difference between the maximum and minimum grayscale values ​​of each pixel in the area to be detected.

[0132] Step S163 : When the image grayscale information does not meet the preset grayscale condition, the visual inspection device sends a brightness adjustment instruction to the light source controller.

[0133] Step S164 : The light source controller adjusts the brightness of the light source in the visual inspection system in response to the brightness adjustment instruction.

[0134] During implementation, the preset grayscale condition may include but is not limited to at least one of a preset mean value range, a preset range threshold, and the like.

[0135] Among them, the preset grayscale conditions and brightness adjustment instructions can be pre-set according to actual needs, and the embodiments of the present disclosure are not limited to this.

[0136] In some embodiments, the preset grayscale condition includes a preset mean range of grayscale values. If the mean grayscale value of each pixel in the area to be inspected is higher than the upper limit of the preset mean range, the visual inspection device may send a first brightness adjustment instruction to the light source controller to instruct the light source to dim the brightness; upon receiving the first brightness adjustment instruction, the light source controller may lower the brightness level of the light source. If the mean grayscale value of each pixel in the area to be inspected is lower than the lower limit of the preset mean range, the visual inspection device may send a second brightness adjustment instruction to the light source controller to instruct the light source to brighten the brightness; upon receiving the second brightness adjustment instruction, the light source controller may increase the brightness level of the light source.

[0137] In this way, when the grayscale information of the image does not meet the preset grayscale conditions, the visual inspection device sends a brightness adjustment instruction to the light source controller to adjust the brightness of the light source in the visual inspection system. This can achieve self-adaptation of the light source brightness in the visual inspection scene, so as to improve the consistency of the grayscale information of the image captured by the image acquisition device, thereby further improving the stability of the imaging effect of the image acquisition device and reducing the error of the detection data.

[0138] In some embodiments, the image grayscale information includes the average grayscale value of each pixel in the area to be detected.

[0139] The above step S163 may include the following step S171:

[0140] In step S171 , when the grayscale value mean exceeds a preset mean range, the visual inspection device sends a brightness adjustment instruction to the light source controller.

[0141] It can be understood that the mean grayscale value of each pixel in the area to be detected refers to the average value of the grayscale values ​​of each pixel in the area to be detected.

[0142] In this way, the grayscale information consistency of the image captured by the image acquisition device can be further improved by controlling the grayscale value mean of each pixel in the detection area.

[0143] In some embodiments, the image grayscale information also includes the grayscale value extremes of each pixel in the area to be detected.

[0144] The above method may further include the following step S181:

[0145] Step S181: When the grayscale value range exceeds the range threshold, the visual inspection device outputs a first prompt message.

[0146] The first prompt information may be any appropriate prompt information, which is used to remind the operator that the current battery product, lens or light source may have problems such as foreign matter shading or reflection.

[0147] In this way, due to the presence of foreign objects blocking or reflecting light in battery products, lenses or light sources, the grayscale values ​​of each pixel in the area to be inspected may differ too much. Therefore, when the extreme difference of the grayscale values ​​of each pixel in the area to be inspected exceeds the extreme difference threshold, the visual inspection equipment outputs a first prompt message, which can remind the operator to check for abnormalities in time, improve the stability of the imaging effect of the image acquisition equipment, and reduce the over-kill rate of visual inspection.

[0148] In some embodiments, the above method may further include the following steps S191 to S192:

[0149] Step S191: The visual inspection device records the number of times the brightness of the light source in the visual inspection system is continuously adjusted.

[0150] Step S192: When the number of times exceeds the threshold, the visual inspection device outputs a second prompt message.

[0151] It is understandable that if the image grayscale information of the area to be detected in the image to be identified cannot meet the preset grayscale conditions after adjusting the brightness of the light source in the visual detection system for multiple consecutive times, it may be that there is an abnormality in the current light source.

[0152] In this way, when the number of times the brightness of the light source in the visual inspection system is continuously adjusted exceeds the threshold, the second prompt information is output to remind the operator to detect the light source abnormality in time and reduce the problem of poor imaging effect of the image acquisition equipment due to the light source abnormality.

[0153] In some embodiments, when the number of times does not exceed the number threshold, if the visual detection device detects that the image grayscale information does not meet the preset grayscale condition, it can trigger the image acquisition device to re-capture the image to be identified to determine whether it is necessary to adjust the brightness of the light source, and after re-capturing the image to be identified, the number of times the brightness of the light source in the visual detection system is continuously adjusted is increased by 1.

[0154] The present disclosure provides a battery production line, as shown in FIG1 , which includes:

[0155] Control device 110 and visual inspection system 120, visual inspection system 120 includes image acquisition device 121 and visual inspection device 122; wherein:

[0156] The control device 110 is used to control the image acquisition device 121 to move to the current working position, and control the image acquisition device 121 to acquire an image of the battery product to be inspected at the current working position to obtain an image to be identified;

[0157] The visual detection device 122 is used to determine the current field of view size of the image acquisition device 121 based on the image to be recognized, and determine the field of view difference between the current field of view size and the reference field of view size;

[0158] The visual detection device 122 is configured to determine a target working position of the image acquisition device 121 based on a reference field of view size and a field of view angle of the image acquisition device when the field of view difference does not satisfy a preset field of view condition, and transmit the target working position to the control device;

[0159] The control device 110 is used to control the image acquisition device 121 to move to a target working position.

[0160] In the battery production line of the embodiment of the present disclosure, the control device controls the image acquisition device to capture images of the battery product to be inspected at the current working position to obtain the image to be identified; the visual inspection device determines the current field of view size of the image acquisition device based on the image to be identified, and determines the field of view difference between the current field of view size and the reference field of view size; when the field of view difference does not meet the preset field of view condition, the visual inspection device determines the target working position of the image acquisition device based on the reference field of view size and the field of view angle of the image acquisition device, and sends the target working position to the control device; the control device controls the image acquisition device to move to the target working position. In this way, the field of view size of the image acquisition device in the battery production line can be consistently controlled, and the automatic deviation correction of the working position of the image acquisition device can be realized to improve the consistency of the field of view size of the image captured by the image acquisition device, thereby improving the stability of the imaging effect of the image acquisition device and reducing the error of the detection data. In addition, since the image acquisition device can automatically correct the working position, the workload of manual debugging of the image acquisition device can be reduced, and the deployment cycle of the image acquisition device can be shortened.

[0161] In some embodiments, referring to FIG3 , the battery production line 100 further includes a testing machine 130 , on which the battery products to be tested are placed;

[0162] The visual inspection device 122 is used to determine a reference field of view size based on the machine type of the inspection machine 130 .

[0163] In this way, for the same type of detection machines, the same reference field of view size can be used for management and control, thereby improving the field of view consistency of the image acquisition device when acquiring images for the same type of detection machines.

[0164] In some embodiments, the visual detection device is used to: determine the mapping relationship between the image coordinate system of the image to be identified and the physical coordinate system; and determine the current field of view size of the image to be identified based on the image size of the image to be identified and the mapping relationship.

[0165] In this way, the current field of view size of the image to be recognized can be determined quickly and accurately according to the image size of the image to be recognized and the mapping relationship between the image coordinate system where the image to be recognized is located and the physical coordinate system.

[0166] In some embodiments, referring to FIG7 , the visual inspection system 120 further includes a light source controller 123 ;

[0167] The visual detection device 122 is used to locate the area to be detected from the image to be recognized and determine the image grayscale information within the area to be detected; if the image grayscale information does not meet the preset grayscale condition, send a brightness adjustment instruction to the light source controller 123;

[0168] The light source controller 123 is used to adjust the brightness of the light source in the visual inspection system in response to the brightness adjustment instruction.

[0169] In this way, when the grayscale information of the image does not meet the preset grayscale conditions, the visual inspection device sends a brightness adjustment instruction to the light source controller to adjust the brightness of the light source in the visual inspection system. This can achieve self-adaptation of the light source brightness in the visual inspection scene, so as to improve the consistency of the grayscale information of the image captured by the image acquisition device, thereby further improving the stability of the imaging effect of the image acquisition device and reducing the error of the detection data.

[0170] The following uses the visual inspection scenario in the bare cell appearance inspection process of the lithium battery production process as an example to illustrate the application of the embodiments of the present disclosure in actual scenarios.

[0171] In the process of inspecting the appearance of bare cells in the lithium battery production process, a CCD visual inspection system can be used to inspect the appearance size and defects of bare cells. The visual inspection method provided by the embodiment of the present disclosure can control the imaging field size and optical imaging grayscale value of the same type of machine, thereby improving the consistency of optical imaging during image acquisition by the same type of machine, and can horizontally expand and reuse the same type of machine, reduce the training cycle of the control model, shorten the deployment cycle of the CCD visual inspection system, and reduce labor costs. Among them, the CCD visual inspection system may include a CCD camera, a visual inspection device, a light source, and a light source controller.

[0172] Figure 8 is a schematic diagram of an application scenario of a visual inspection method in a battery production line provided by an embodiment of the present disclosure. As shown in Figure 8, this method can be applied to the appearance inspection process of a bare battery cell. The battery product to be inspected can be placed on the inspection machine 310. A drive component 320 that can move up and down along the linear rail 350 can be provided above the inspection machine 310. The CCD camera 330 can be fixedly connected to the drive component 320. The PLC 340 can drive the CCD camera 330 to move up and down by controlling the drive component 320 to move up and down along the linear rail 350, so that the CCD camera reaches the current working position. The PLC 340 can send an image acquisition instruction to the CCD camera 330 in response to the CCD camera 330 reaching the current working position. The CCD camera 330 can perform image acquisition on the battery product to be inspected in response to the image acquisition instruction to obtain an image to be identified. In addition, the drive component 320 and the CCD camera 330 as a whole can be driven by the servo motor 360 to move in the horizontal direction. The visual inspection device (not shown in the figure) in the CCD visual inspection system can also adjust the brightness of the light source 380 by sending a brightness adjustment instruction to the light source controller 370.

[0173] The visual inspection method in the battery production line provided by the embodiment of the present disclosure may include a field of view consistency control process and a light source adaptive control process.

[0174] FIG9 is a schematic diagram of a field of view consistency control process provided by an embodiment of the present disclosure. As shown in FIG9 , the field of view consistency control process includes the following steps S801 to S809:

[0175] Step S801: PLC drives the CCD camera to a preset photographing point.

[0176] Here, the preset photographing point may be a point on the vertical axis (Z axis) of the driving component.

[0177] Step S802: The PLC sends a photo taking instruction to trigger the CCD camera to take a photo.

[0178] Step S803: The visual inspection device uses the calibration matrix of the CCD camera to perform orthogonal processing on the image to be identified obtained by taking the photo;

[0179] In step S804 , the visual inspection device determines the current field of view size of the CCD camera through the image size of the image to be recognized and the calibration matrix.

[0180] Step S805 , the visual inspection device determines whether the visual field difference between the current visual field size and the reference visual field size exceeds a size difference threshold;

[0181] If so, go to step S806; if not, go to step S802.

[0182] Step S806: The visual inspection device obtains the hardware parameters of the CCD camera.

[0183] Among them, the hardware parameters of the CCD camera include the focal length of the lens and the diagonal length of the CCD camera photosensitive chip.

[0184] Step S807: The visual inspection device calculates the field of view angle of the CCE camera lens.

[0185] Step S808: The visual inspection device determines the target distance based on the reference field size and field angle;

[0186] In step S809 , the visual inspection device feeds back the target distance to the PLC, so that the PLC controls the CCD camera to reach the target photographing point based on the target distance.

[0187] Here, the preset photographing point and the target photographing point correspond to the current working position and the target working position in the aforementioned embodiment, respectively.

[0188] The visual inspection method for a battery production line provided by an embodiment of the present disclosure is based on the above-mentioned field of view consistency control process. By adopting a CCD visual inspection system to communicate with the PLC, the current field of view size of the CCD camera taking an image is fed back to the PLC in real time to control the driving component to perform height correction on the CCD camera's photographing point, thereby improving the imaging quality of machines of the same type and reducing the situation where errors in inspection data are caused by changes in the field of view size of the CCD camera.

[0189] FIG10 is a schematic diagram of a light source adaptive control process provided by an embodiment of the present disclosure. As shown in FIG10 , the light source adaptive control process includes the following steps S901 to S908:

[0190] Step S901: PLC drives the CCD camera to a preset photographing point.

[0191] Here, the preset photographing point may be a point on the vertical axis (Z axis) of the driving component.

[0192] Step S902: The PLC sends a photo taking instruction to trigger the CCD camera to take a photo.

[0193] Step S903: The visual inspection device locates the area to be inspected from the image to be identified obtained by taking the photo;

[0194] Step S904: The visual inspection device obtains image grayscale information of the area to be inspected.

[0195] Step S905: The visual inspection device determines whether the grayscale information of the image meets a preset grayscale condition;

[0196] If so, go to step S901; if not, go to step S906.

[0197] Step S906: The visual inspection device adjusts the brightness level of the light source and records the number of times the brightness of the light source in the visual inspection system is continuously adjusted.

[0198] Step S907: The visual inspection device determines whether the number of times exceeds a threshold number.

[0199] If so, go to step S902; if not, go to step S908.

[0200] Step S908: The visual inspection equipment notifies the PLC to alarm and shut down.

[0201] The visual inspection method in the battery production line provided by the embodiment of the present disclosure is based on the above-mentioned light source adaptive control process, and can perform various error prevention operations. For example, the PLC cannot start working when the CCD visual inspection system is not turned on, the light source is adaptively closed-loop, and when the number of times the light source brightness is adaptively adjusted reaches a threshold, the PLC is notified to alarm and shut down, and engineers analyze the cause of the abnormality, thereby improving the consistency and stability of the imaging effect.

[0202] It should be pointed out here that the above description of the various embodiments tends to emphasize the differences between the various embodiments, and the same or similar aspects can be referenced to each other.

[0203] It should be understood that “one embodiment” or “an embodiment” mentioned throughout the specification means that specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present disclosure. Therefore, “in one embodiment” or “in an embodiment” appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in the various embodiments of the present disclosure, the size of the serial numbers of the above-mentioned steps / processes does not mean the order of execution, and the execution order of each step / process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present disclosure. The serial numbers of the embodiments of the present disclosure are for description only and do not represent the advantages and disadvantages of the embodiments.

[0204] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0205] In the several embodiments provided in the present disclosure, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of units is merely a logical function division. In actual implementation, there may be other division methods, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of devices or units can be electrical, mechanical or other forms.

[0206] The units described above as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; they may be located in one place or distributed across multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment. In addition, the functional units in the various embodiments of the present disclosure may all be integrated into one processing unit, or each unit may be separately used as a unit, or two or more units may be integrated into one unit; the above-mentioned integrated units may be implemented in the form of hardware or in the form of hardware plus software functional units.

[0207] The above are only implementation methods of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any changes or replacements that can be easily conceived by any technician familiar with this technical field within the technical scope disclosed in this disclosure should be covered by the protection scope of the present disclosure.

Claims

1. A visual inspection method for a battery production line, the battery production line comprising a control device and a visual inspection system, the visual inspection system comprising an image acquisition device and a visual inspection device, the visual inspection method comprising: The control device controls the image acquisition device to acquire an image of the battery product to be inspected at the current working position to obtain an image to be identified; The visual detection device determines the current field of view size of the image acquisition device based on the image to be recognized, and determines the field of view difference between the current field of view size and the reference field of view size; When the visual field difference does not satisfy the preset visual field condition, the visual inspection device determines the target working position of the image acquisition device based on the reference visual field size and the field of view angle of the image acquisition device, and sends the target working position to the control device; The control device controls the image acquisition device to move to the target working position.

2. The visual inspection method in a battery production line according to claim 1, wherein: The battery production line further includes a testing machine, and the battery product to be tested is placed on the testing machine; the method further includes: The visual inspection device determines the reference field of view size based on the machine type of the inspection machine.

3. The visual inspection method in a battery production line according to claim 1 or 2, wherein: The determining, based on the image to be recognized, the current field of view size of the image acquisition device includes: Determine a mapping relationship between an image coordinate system and a physical coordinate system where the image to be identified is located; Based on the image size of the image to be recognized and the mapping relationship, a current field of view size of the image to be recognized is determined.

4. The visual inspection method in a battery production line according to claim 3, wherein: The current field of view size includes the diagonal length of the current field of view of the image acquisition device; The determining, based on the image size of the image to be recognized and the mapping relationship, the current field of view size of the image to be recognized includes: Determining image coordinates corresponding to two diagonal points of the image to be identified based on the image size; Determining the physical coordinates corresponding to the two diagonal points based on the mapping relationship and the image coordinates corresponding to the two diagonal points; Based on the physical coordinates corresponding to the two diagonal points, the diagonal length of the current field of view of the image acquisition device is determined.

5. The visual inspection method in a battery production line according to any one of claims 1 to 4, wherein: The preset field of view condition includes a size difference threshold, and the image acquisition device has a target distance between the target working position and the battery product; When the field of view difference does not satisfy the preset field of view condition, determining the target working position of the image acquisition device based on the reference field of view size and the field of view angle of the image acquisition device includes: When the field of view difference value exceeds the size difference threshold, determining the target distance based on the reference field of view size and the field of view angle; Based on the target distance, the target working position is determined.

6. The visual inspection method in a battery production line according to claim 5, wherein: The current field of view size includes the diagonal length of the current field of view of the image acquisition device; Before determining the target working position of the image acquisition device based on the reference field of view size and the field of view angle of the image acquisition device, the method further includes: Obtaining the diagonal length of the image sensor in the image acquisition device and the focal length of the lens of the image acquisition device; The field of view angle is determined based on the diagonal length and the focal length of the lens.

7. The visual inspection method in a battery production line according to any one of claims 1 to 6, wherein: The visual inspection system further includes a light source controller; and the method further includes: The visual detection device locates the area to be detected from the image to be identified; The visual inspection device determines the image grayscale information within the area to be inspected; The visual inspection device sends a brightness adjustment instruction to the light source controller when the grayscale information of the image does not meet the preset grayscale condition; The light source controller adjusts the brightness of the light source in the visual inspection system in response to the brightness adjustment instruction.

8. The visual inspection method in a battery production line according to claim 7, wherein: The image grayscale information includes the average grayscale value of each pixel in the area to be detected; When the grayscale information of the image does not meet a preset grayscale condition, the visual inspection device sends a brightness adjustment instruction to the light source controller, including: When the grayscale value mean exceeds a preset mean range, the visual detection device sends a brightness adjustment instruction to the light source controller.

9. The visual inspection method in a battery production line according to claim 8, wherein: The image grayscale information also includes the grayscale value extreme difference of each pixel in the area to be detected; The method further comprises: The visual inspection device outputs a first prompt message when the grayscale value range exceeds the range threshold.

10. The visual inspection method in a battery production line according to any one of claims 7 to 9, wherein: The method further comprises: The visual inspection device records the number of times the brightness of the light source in the visual inspection system is continuously adjusted; The visual inspection device outputs a second prompt message when the number of times exceeds a threshold number of times.

11. A battery production line, comprising: Control equipment and visual inspection system, the visual inspection system includes an image acquisition device and a visual inspection device; wherein: The control device is used to control the image acquisition device to move to a current working position, and control the image acquisition device to acquire an image of the battery product to be inspected at the current working position to obtain an image to be identified; The visual detection device is configured to determine a current field of view size of the image acquisition device based on the image to be recognized, and determine a field of view difference between the current field of view size and a reference field of view size; The visual detection device is configured to determine a target working position of the image acquisition device based on the reference field of view size and the field of view angle of the image acquisition device when the field of view difference value does not satisfy a preset field of view condition, and send the target working position to the control device; The control device is used to control the image acquisition device to move to the target working position.

12. The battery production line according to claim 11, wherein: The battery production line also includes a testing machine, and the battery product to be tested is placed on the testing machine; The visual inspection device is used to determine the reference field of view size based on the machine type of the inspection machine.

13. The battery production line according to claim 11 or 12, wherein: The visual detection device is used to: determine the mapping relationship between the image coordinate system of the image to be identified and the physical coordinate system; and determine the current field of view size of the image to be identified based on the image size of the image to be identified and the mapping relationship.

14. The battery production line according to claim 13, wherein: The current field of view size includes the diagonal length of the current field of view of the image acquisition device; The visual detection device is used to: determine the image coordinates corresponding to the two diagonal points of the image to be identified based on the image size; determine the physical coordinates corresponding to the two diagonal points based on the mapping relationship and the image coordinates corresponding to the two diagonal points; determine the physical coordinates corresponding to the two diagonal points based on the physical coordinates corresponding to the two diagonal points. The diagonal length of the current field of view of the image acquisition device.

15. The battery production line according to any one of claims 11 to 14, wherein: The preset field of view condition includes a size difference threshold, and the image acquisition device has a target distance between the target working position and the battery product; The visual inspection device is further used to: determine the target distance based on the reference field of view size and the field of view angle when the field of view difference value exceeds the size difference threshold; and determine the target working position based on the target distance.

16. The battery production line according to claim 15, wherein: The current field of view size includes the diagonal length of the current field of view of the image acquisition device; The visual inspection device is configured to obtain a diagonal length of an image sensor in the image acquisition device and a focal length of a lens of the image acquisition device before determining a target working position of the image acquisition device based on the reference field of view size and the field of view angle of the image acquisition device; The field of view angle is determined based on the diagonal length and the focal length of the lens.

17. The battery production line according to any one of claims 11 to 16, wherein: The visual inspection system also includes a light source controller; The visual inspection device is configured to locate an area to be inspected from the image to be identified and determine image grayscale information within the area to be inspected; and send a brightness adjustment instruction to the light source controller if the image grayscale information does not meet a preset grayscale condition. The light source controller is used to adjust the brightness of the light source in the visual inspection system in response to the brightness adjustment instruction.

18. The battery production line according to claim 17, wherein: The image grayscale information includes the average grayscale value of each pixel in the area to be detected; The visual inspection device is used to send a brightness adjustment instruction to the light source controller when the grayscale value mean exceeds a preset mean range.

19. The battery production line according to claim 18, wherein: The image grayscale information also includes the grayscale value extreme difference of each pixel in the area to be detected; The visual inspection device is used to output first prompt information when the grayscale value range exceeds the range threshold.

20. The battery production line according to any one of claims 17 to 19, wherein: The visual inspection device is used to: record the number of times the brightness of the light source in the visual inspection system is continuously adjusted; and output a second prompt message when the number exceeds a threshold.

Images