Printing deviation correction method and device, printing system and computer readable storage medium

Abstract

The embodiment of the invention discloses a printing deviation correction method and device, a printing system and a computer readable storage medium, an image collection device is used for carrying out image collection on a first printing medium moving to a collection position to obtain a first image, deviation pose information of the first printing medium deviating from a target pose is determined according to the first image, and the deviation pose information of the first printing medium deviating from the target pose is obtained. And obtaining a reference printing image matched with the target pose, performing transformation processing on the reference printing image according to the deviation pose information to obtain a first printing image matched with the first printing medium, and controlling one or more spray holes of the printing device according to the first printing image to print the first printing medium moved to the first station. The controller can perform transformation processing on the reference printing image matched with the target pose according to the deviation pose information between the first printing medium and the target pose to obtain the first printing image, so that a pattern printed on the first printing medium can also be aligned, and accurate printing is realized.

Description

Technical Field

[0001] The present application relates to the field of inkjet printing technology, and in particular to a printing deviation correction method, device, printing system and computer-readable storage medium. Background Art

[0002] At present, the traditional inkjet printing system needs to fix the position of the printing medium in order to print on the printing medium. If the printing medium is placed in a position that deviates, the pattern printed on the printing medium will also be deflected, and accurate printing cannot be achieved, and the inkjet printing accuracy is low. Summary of the invention

[0003] The embodiments of the present application disclose a printing deviation correction method, device, printing system and computer-readable storage medium, which can improve the accuracy of inkjet printing.

[0004] The present application embodiment discloses a printing deviation correction method, which is applied to a controller of a printing system, wherein the printing system further comprises an image acquisition device, a transfer device and a printing device, wherein the transfer device is used to carry a first printing medium, and first transfer the first printing medium to a collection position corresponding to the image acquisition device, and then transfer the first printing medium to a first station corresponding to the printing device; the method comprises:

[0005] Capturing an image of the first printing medium moved to the acquisition position by the image acquisition device to obtain a first image;

[0006] Determining deviation posture information of the first printing medium from a target posture according to the first image;

[0007] Acquire a reference printed image matching the target pose;

[0008] According to the deviation posture information, transform the reference print image to obtain a first print image matching the first print medium;

[0009] According to the first printing image, one or more nozzles of the printing device are controlled to print on the first printing medium moved to the first station.

[0010] As an optional implementation, the first printing medium is provided with one or more markers, and the deviation posture information includes deviation posture data between the first posture corresponding to the first printing medium and the target posture; and determining the deviation posture information of the first printing medium from the target posture according to the first image includes:

[0011] Identify each marker in the first image, and determine the image position of each marker in the first image;

[0012] Determining a first position corresponding to the first printing medium based on the image positions corresponding to the respective markers;

[0013] Determine deviation pose data between the first pose and the target pose.

[0014] As an optional implementation, the first printing medium is provided with a first marker and a second marker, the first posture includes first position data and first angle data corresponding to a midpoint between the first marker and the second marker, and the target posture includes target position data and target angle data corresponding to the midpoint;

[0015] The determining of deviation posture data between the first posture and the target posture comprises:

[0016] determining deviation position data between the first position data and the target position data;

[0017] Determine a deviation angle data between the first angle data and the target angle data.

[0018] As an optional implementation manner, determining, according to the first image, the deviation posture information of the first printing medium from the target posture includes:

[0019] Performing image matching between the first image and a second image corresponding to the target posture to obtain a plurality of feature point pairs, each feature point pair comprising a first feature point in the first image and a second feature point in the second image that matches the first feature point; the second image is acquired by an image acquisition device;

[0020] Determine, based on the plurality of feature point pairs, a deviation distance between a first feature point and a second feature point of each feature point pair;

[0021] Deviated posture information of the first printing medium deviating from the target posture is determined according to the deviation distances respectively corresponding to the plurality of groups of feature point pairs.

[0022] As an optional implementation, the printing surface of the first printing medium includes a curved surface, and the printing system further includes a height acquisition device; and the method further includes:

[0023] Scanning the first printing medium moved to the acquisition position by the height acquisition device to obtain distance information between the printing surface of the first printing medium and the height acquisition device;

[0024] Determine the height information between the printing surface and the carrying surface of the transfer device according to the distance information;

[0025] Determining curvature information of a printing surface of the first printing medium according to the height information;

[0026] The step of controlling one or more nozzles of the printing device according to the first printing image to print the first printing medium moved to the first station includes:

[0027] adjusting the number of pixels included in the first printed image according to the curvature information to obtain a second printed image;

[0028] According to the second printing image, one or more nozzles of the printing device are controlled to print on the first printing medium moved to the first station.

[0029] As an optional implementation manner, adjusting the number of pixels included in the first printed image according to the curvature information to obtain the second printed image includes:

[0030] dividing the first printed image into a plurality of image regions according to the curvature information;

[0031] Determining the adjustment ratio corresponding to each of the image areas according to the height change information corresponding to the printing surface corresponding to each of the image areas;

[0032] According to the adjustment ratio corresponding to each of the image areas, the number of pixels included in each of the image areas is adjusted to obtain a second printed image.

[0033] As an optional implementation, the height information includes height data corresponding to a plurality of points in the print surface; the height change information corresponding to the print surface corresponding to the image area includes a slope of the print surface corresponding to the image area; and the method further includes:

[0034] Determine the highest point and the lowest point of the printing surface corresponding to the first image area; wherein the highest point is the point with the largest height data in the printing surface corresponding to the first image area, and the lowest point is the point with the smallest height data in the printing surface corresponding to the first image area; the first image area is any one of the multiple image areas;

[0035] The slope of the printing surface corresponding to the first image area is determined based on the image position in the first image area corresponding to the highest point, the height data corresponding to the highest point, the image position in the first image area corresponding to the lowest point, and the height data corresponding to the lowest point.

[0036] The present application embodiment discloses a printing deflection correction device, which is applied to a controller of a printing system. The printing system further includes an image acquisition device, a transfer device, and a printing device. The transfer device is used to carry a first printing medium and first transfer the first printing medium to a collection position corresponding to the image acquisition device, and then transfer the first printing medium to a first station corresponding to the printing device. The printing deflection correction device includes:

[0037] An image acquisition module, configured to acquire an image of the first printing medium moved to the acquisition position through the image acquisition device to obtain a first image;

[0038] A first determining module, configured to determine, based on the first image, deviation posture information of the first printing medium from a target posture;

[0039] An image acquisition module, used to acquire a reference printed image matching the target pose;

[0040] an image transformation module, configured to transform the reference print image according to the deviation posture information to obtain a first print image matching the first print medium; and

[0041] The printing control module is used to control one or more nozzles of the printing device according to the first printing image to print the first printing medium moved to the first station.

[0042] The present application embodiment discloses a printing system, including:

[0043] Image acquisition device;

[0044] Printing device;

[0045] A transfer device, used for carrying a first printing medium, and transferring the first printing medium to a collection position corresponding to the image collection device, and then transferring the first printing medium to a first station corresponding to the printing device; and

[0046] The controller includes a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor implements any one of the printing deviation correction methods disclosed in the embodiments of the present application.

[0047] An embodiment of the present application discloses a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, any one of the printing deviation correction methods disclosed in the embodiment of the present application is implemented.

[0048] Compared with the related art, the embodiments of the present application have the following beneficial effects:

[0049] The embodiment of the present application provides a printing deviation correction method, device, printing system and computer-readable storage medium. The printing system includes a controller, an image acquisition device, a transfer device and a printing device. The transfer device is used to carry a first printing medium, and first transfer the first printing medium to a collection position corresponding to the image acquisition device, and then transfer the first printing medium to a first station corresponding to the printing device. The controller uses the image acquisition device to capture an image of the first printing medium moved to the collection position to obtain a first image. Based on the first image, the deviation posture information of the first printing medium from the target posture is determined, and a reference printing image matching the target posture is obtained. Based on the deviation posture information, the reference printing image is transformed to obtain a first printing image matching the first printing medium. Based on the first printing image, one or more nozzles of the printing device are controlled to print the first printing medium moved to the first station. The controller can first determine the deviation posture information between the first printing medium and the target posture, and then transform the reference printing image that matches the target posture according to the deviation posture information, so that the reference printing image can be adjusted accordingly to obtain the first printing image that matches the first printing medium, so that even if the posture of the first printing medium changes relative to the target, the pattern printed on the first printing medium can also be aligned to achieve precise printing.

[0050] At the same time, the transformation processing of the reference printed image matching the target posture is completed by software, which has an extremely fast response speed. Compared with mechanical adjustment, the adjustment speed is faster and mechanical wear is avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0052] Figure 1 It is a structural schematic diagram of a printing system disclosed in an embodiment of the present application;

[0053] Figure 2 This is a method disclosed in the embodiments of the present application. Figure 1 A partial enlarged view of the middle A;

[0054] Figure 3 This is a method disclosed in the embodiments of the present application. Figure 1 A partial enlarged view of point B in the middle;

[0055] Figure 4 is a structural schematic diagram of a positioning component from another perspective disclosed in an embodiment of the present application;

[0056] Figure 5 This is a method disclosed in the embodiments of the present application. Figure 1 A partial enlarged view of point C in the middle;

[0057] Figure 6 is a bottom schematic diagram of a print head disclosed in an embodiment of the present application;

[0058] Figure 7 is a schematic diagram of a printing process disclosed in an embodiment of the present application;

[0059] Figure 8 It is a flow chart of a printing correction method disclosed in an embodiment of the present application;

[0060] Fig. 9 is a schematic diagram of a first posture corresponding to a first printing medium disclosed in an embodiment of the present application;

[0061] Fig.10 It is a flow chart of a posture deviation information determination process disclosed in an embodiment of the present application;

[0062] Fig.11 It is a flowchart of another posture deviation information determination process disclosed in an embodiment of the present application;

[0063] Fig.12 It is a flow chart of another printing correction method disclosed in an embodiment of the present application;

[0064] Fig.13 It is a schematic diagram of the correspondence between the pixel points of a printed image and the printing points of a printing surface disclosed in an embodiment of the present application;

[0065] Fig.14 is a flow chart of a process for obtaining a second printed image disclosed in an embodiment of the present application;

[0066] Fig.15 It is a structural schematic diagram of a printing correction device disclosed in an embodiment of the present application;

[0067] Fig.16 It is a schematic diagram of the structure of a controller of a printing system disclosed in an embodiment of the present application. DETAILED DESCRIPTION

[0068] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0069] It should be noted that the terms "including" and "having" and any variations thereof in the embodiments of the present application and the accompanying drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0070] Please refer to Figure 1 , which shows a schematic diagram of the structure of a printing system provided by an embodiment of the present application. Figure 1 As shown, the printing system may include a transfer device 110, a positioning component 120, a printing device 130, and a controller ( Figure 1 (not shown). The positioning assembly 120 may include an image acquisition device, and the transfer device 110 is used to carry the printing medium to be printed, and first transfer the printing medium to the acquisition position corresponding to the image acquisition device, and then transfer the printing medium to the first station corresponding to the printing device 130. The image acquisition device can be used to capture an image of the first printing medium moved to the acquisition position to obtain a first image. The printing device 130 can be used to print the printing medium moved to the first station. Optionally, please continue to refer to Figure 1 The transfer device is used to drive the printing medium to move along the first direction X.

[0071] In some embodiments, please refer to Figure 1 The transfer device 110 may include an adsorption fixture 111 and a linear motor 112. The linear motor 112 extends along a first direction X, and the adsorption fixture 111 is used to fix the printing medium on the adsorption fixture 111 by vacuum adsorption.

[0072] Optionally, refer to Figure 2 The transfer device may also include a connecting fixture 210 and a fixture mounting support 220. The fixture mounting support 220 is used to provide a mounting surface for the adsorption fixture 111. That is, the adsorption fixture 111 is installed above the fixture mounting support 220. The connecting fixture 210 is respectively connected to the linear motor 112 and the fixture mounting support 220 to ensure a stable connection between the linear motor 112 and the adsorption fixture 111, so that the adsorption fixture 111 can run along the first direction X under the drive of the linear motor 112.

[0073] Optionally, please continue to refer to Figure 2 The transfer device may further include a vacuum display meter 230, which is used to display the vacuum adsorption value between the adsorption fixture 111 and the printing medium. When the vacuum adsorption value is greater than a preset threshold, it can be considered that the printing medium has been adsorbed well and the printing medium can be relatively stably located on the adsorption fixture.

[0074] In some embodiments, please refer to Figure 3 , which shows Figure 1 A partial enlarged view of point B in the figure. Figure 3 As shown, the positioning assembly may include an image acquisition device 310, a first gantry column 320, and an image acquisition mounting member 330. The first gantry column 320 is used to provide a mounting substrate surface for other components of the positioning assembly. The image acquisition mounting member 330 is fixedly connected to the first gantry column 320 and the image acquisition device 310, respectively, so as to mount the image acquisition device 310 on the first gantry column 320, and the printing medium passes under the image acquisition device 310 under the drive of the linear motor.

[0075] Optionally, the positioning component may include multiple image acquisition devices 310 to acquire the image of the complete printing medium. The image acquisition device can scan the position and contour of the printing medium to obtain a two-dimensional image corresponding to the printing medium, providing a positioning and position basis for subsequent product printing.

[0076] In some embodiments, the positioning assembly may further include a light source assembly 340 and a light source mounting member 350, wherein the light source mounting member 350 is connected to the first gantry column 320 and the light source assembly 340, respectively, so as to mount the light source 340 on the first gantry column 320. The light source assembly 340 may be used to provide brightness fill light for the image acquisition device 310.

[0077] Please refer to Figure 4 , which shows a structural schematic diagram of the positioning component from another perspective, such as Figure 4 As shown, the printing system may further include a height acquisition device 410 and a height sensing mounting member 420. The height sensing mounting member 420 is respectively connected to the first gantry column 320 and the height acquisition device 410. The printing medium passes under the height acquisition device 410 driven by the linear motor, and the height acquisition device 410 can be used to acquire the distance between the printing surface of the printing medium and the height acquisition device 410.

[0078] Optionally, the height acquisition device 410 is installed on the first surface of the first gantry column 320 through the height sensing mounting member 420, and the image acquisition device is installed on the second surface of the first gantry column 320 through the image acquisition mounting member. The first surface and the second surface are opposite surfaces. By arranging the height acquisition device 410 and the image acquisition device on different surfaces of the first gantry column 320, the space of the first gantry column 320 can be fully utilized.

[0079] Please refer to Figure 5 , which shows Figure 1 A partial enlarged view of point C in the middle. Figure 5As shown, the printing device may include a second gantry column 510, a print head 520, and a printing mounting member 530. The printing mounting member 530 is connected to the second gantry column 510 and the print head 520, respectively. The printing medium passes under the print head 520 under the drive of the linear motor, and the print head 520 prints a pattern on the printing medium moved to the first station.

[0080] Please refer to Figure 6 , which shows a bottom schematic diagram of a print head provided by an embodiment of the present application. Figure 6 As shown, the print head may include a plurality of nozzles 610, and the plurality of nozzles 610 are arranged in one or more rows along the second direction Y, and each nozzle 610 can work independently, that is, each nozzle 610 can independently choose whether to eject ink. Figure 6 As shown, the print head includes 8 rows of nozzles, and the spacing between two adjacent rows of nozzles can be equal or unequal.

[0081] Please refer to Figure 7 , which shows a schematic diagram of a printing process provided by an embodiment of the present application. Figure 7 As shown, the length of the print head 710 along the second direction Y is greater than or equal to the length of the print medium 720 along the second direction Y, thereby ensuring that when the print medium 720 moves along the first direction, the pattern can be printed at the corresponding position of the print medium 720 through the print head 710 without any printing blind spots.

[0082] Please refer to Figure 8 , which shows a flow chart of a printing correction method provided in an embodiment of the present application. The method can be applied to a controller of a printing system, and the printing system includes an image acquisition device, a transfer device and a printing device. The transfer device is used to carry a first printing medium, and first transfer the first printing medium to a collection position corresponding to the image acquisition device, and then transfer the first printing medium to a first station corresponding to the printing device.

[0083] like Figure 8 As shown, the printing deflection correction method may include steps 802 to 810.

[0084] Step 802: Use an image acquisition device to acquire an image of a first printing medium moved to a acquisition position to obtain a first image.

[0085] It should be noted that the first printing medium may refer to a medium to be printed, and the printing surface of the first printing medium may include a curved surface or a flat surface. Exemplarily, the printing medium may include but is not limited to paper, a cup, a lens, etc. The acquisition position may refer to a position within the field of view of the image acquisition device. When the transfer device transfers the first printing medium to the acquisition position corresponding to the image acquisition device, the image acquisition device may acquire a first image containing at least part of the first printing medium.

[0086] Exemplarily, the printing system may include one or more image acquisition devices, and the sum of the fields of view of each image acquisition device along the second direction covers the first printing medium along the second direction, which can prevent the omission of a certain part of the first printing medium due to insufficient field of view. The second direction may refer to a direction perpendicular to the moving direction of the transfer device.

[0087] In some embodiments, the image acquisition device may include a line scan camera, the transfer device carries the first printing medium and drives the first printing medium to move along the first direction, the line scan camera acquires images of the first printing medium by scanning line by line, and as the first printing medium moves, the line scan camera captures a series of linear images and stitches them together to form a first image containing the complete first printing medium. It should be noted that the scanning speed of the line scan camera matches the moving speed of the transfer device to ensure the accuracy and proportional consistency of the stitched first image, and to ensure the accuracy of the deviation posture information obtained based on the analysis of the first image.

[0088] In some embodiments, the controller obtains the vacuum value corresponding to the adsorption jig, and when the vacuum value is greater than or equal to the adsorption threshold, the transfer device is triggered to move, so that the first printing medium is sequentially transferred to the acquisition position corresponding to the image acquisition device, and the first printing medium is transferred to the first station corresponding to the printing device. It should be noted that the adsorption threshold can be used to measure whether the adsorption force between the first printing medium and the adsorption jig can make the first printing medium stably located on the adsorption jig. If the vacuum value is greater than or equal to the adsorption threshold, it can be considered that the first printing medium can be stably located on the adsorption jig, that is, the first printing medium will not change its posture due to reasons such as the movement of the transfer device. If the vacuum value is less than the adsorption threshold, it can be considered that the first printing medium cannot be stably located on the adsorption jig.

[0089] In this embodiment, the controller can trigger the movement of the transfer device only when it determines that the vacuum value corresponding to the adsorption jig is greater than or equal to the adsorption threshold value, thereby ensuring that the position of the first printing medium relative to the adsorption jig at the collection position is consistent with the position relative to the adsorption jig at the first workstation, thereby ensuring the printing accuracy of the first printing medium based on the first printing image after the transformation processing.

[0090] Step 804: Determine deviation posture information of the first printing medium from the target posture according to the first image.

[0091] It should be noted that when the posture of the printing medium is the target posture, the printing medium is printed using the reference printing image that matches the target posture, and the print pattern printed on the printing medium meets the printing requirements. The printing requirements include that the print pattern printed on the printing medium is in a suitable position, in a suitable size, and that there are no missing print patterns. In this embodiment, the controller determines the deviation posture information of the first printing medium from the target posture based on the first image, and transforms the reference printing image that matches the target posture based on the deviation posture information to obtain the first printing image that matches the posture of the first printing medium, so that the first printing medium is printed based on the first printing image, and the pattern printed on the first printing medium also meets the printing requirements.

[0092] In some embodiments, before acquiring the first image by an image acquisition device for the first printing medium moved to the acquisition position, the controller acquires the second image by an image acquisition device for the second printing medium moved to the acquisition position, the position of the second printing medium is the target position, and a third printing image is acquired. According to the third printing image, one or more nozzles of the printing device are controlled to print the second printing medium moved to the first station, and it is determined whether the pattern printed on the second printing medium meets the printing requirements. If not, the image parameters of the third printing image are adjusted, and according to the adjusted third printing image, one or more nozzles of the printing device are controlled to print the second printing medium moved to the first station, until it is determined that the pattern printed on the second printing medium meets the printing requirements, and the current third printing image is determined as the reference printing image. It should be noted that the second printing medium and the first printing medium are products of the same type, and the two printing media have similar appearances. Image parameters may include but are not limited to the size, resolution, and posture of the printed pattern. By adjusting the image parameters of the third printed image, the nozzles used by the printing device for printing and / or the printing timing of the nozzles (i.e., the timing of ejecting ink droplets) can be adjusted, thereby changing the size and position of the pattern printed on the second printed image, thereby obtaining a second printed medium that meets the printing requirements.

[0093] In some embodiments, based on the first image, the first posture corresponding to the first printing medium is determined, and the deviation posture data between the first posture and the target posture is determined. It should be noted that the first posture may include postures corresponding to one or more points in the printing surface of the first printing medium, and the first posture corresponding to the first printing medium includes the position data and angle data of the first printing medium in the first image. The position data may be the coordinates of one or more points in the printing surface in the image coordinate system, and the angle data may include the direction of the line connecting the origin of the image coordinate system and the one or more points in the printing surface, and the angle formed with the first axis direction. The first axis direction may be any axis direction in the image coordinate system. Fig. 9 As shown, the first axis direction is the X axis direction. is the direction of the line, the angle data corresponding to point A is θ, and the coordinate data of point A is (x1, y1).

[0094] Step 806: Acquire a reference printed image that matches the target pose.

[0095] Step 808: transform the reference print image according to the deviation posture information to obtain a first print image matching the first print medium.

[0096] It should be noted that when a printed product with a target posture is printed based on the reference print image, a printed medium that meets the printing requirements can be obtained. The controller can store the reference print image, or the reference print image can be stored in a terminal device, and the controller is connected to the terminal device to obtain the reference print image. Transformation processing may include but is not limited to translation transformation, rotation transformation, and scaling transformation. Among them, translation transformation refers to moving the position of the pixel points of the reference print image, and the translation transformation can be achieved by adding a fixed offset to the coordinates of the pixel points in the reference print image. Rotation transformation refers to rotating a certain angle around the center or specified point of the reference print image. Scaling transformation refers to changing the size of the reference print image, including enlarging and reducing.

[0097] Exemplarily, according to the deviation posture information, a transformation process is performed on a reference print image that matches the target posture to obtain a first print image that matches the first posture corresponding to the first print medium.

[0098] In the related art, when the print medium is not placed at the reference position of the transfer device, the print medium is returned to the reference position by adjusting the mechanical position of the print head or the mechanical position of the transfer device. In this embodiment, the reference print image is transformed so that the adjusted first print image matches the first print medium, so that the printing system can adapt to print media with different postures and can achieve accurate printing for print media with different postures. At the same time, the transformation of the reference print image matching the target posture is completed by software, and the response speed is extremely fast. Compared with mechanical adjustment, the adjustment speed is faster and mechanical wear is avoided.

[0099] Step 810: Control one or more nozzles of a printing device according to a first printing image to print on a first printing medium moved to a first station.

[0100] It should be noted that the first printed image includes a plurality of pixels, and the plurality of pixels on the printed image are used to instruct one or more nozzles of the print head to spray ink at a target time. The controller can read the pixel values ​​corresponding to the pixel points of each row and column in the first printed image, and determine the control signals of each nozzle of the printing device according to the plurality of pixel values, and drive the nozzles to perform printing operations at the corresponding time, that is, spray ink droplets, so that the landing points of the plurality of ink droplets sprayed by one or more nozzles correspond to the plurality of pixels of the first printed image one by one. The first printing medium moves along a first direction, and the nozzles spraying ink at different times can form ink dots at different positions of the first printing medium along the first direction. At the same time, different nozzles are selected to spray ink, and ink dots can be printed at different positions of the first printing medium along the second direction.

[0101] In some embodiments, the print head of the printing device remains stationary and prints on the first printing medium moved to the first station, wherein the width of the print head along the second direction is greater than or equal to the width of the first printing medium, thereby ensuring that the first printing medium can be printed even when the print head of the printing device does not move, and the ink droplets can land on the corresponding position on the first printing medium.

[0102] In some embodiments, a first voltage is provided to the printing device, and a landing distance between a landing position of an ink drop ejected from a nozzle of the print head and a target landing position is determined, and if the landing distance is less than or equal to a preset threshold, the first voltage is used as a trigger voltage. If the landing distance is greater than the preset threshold, a parameter of the first voltage is adjusted to obtain the adjusted first voltage, and the operation of providing the first voltage to the printing device continues.

[0103] It should be noted that the parameters of the first voltage provided are different, the ejection speed of the nozzle and the ink droplet size are different, and by adjusting the parameters of the first voltage, the deviation of the ink droplet landing position can be reduced, thereby improving the printing accuracy. The parameters of the first voltage may include the voltage amplitude, voltage pulse width, voltage waveform (such as square wave, trapezoidal wave, sine wave, etc.) of the first voltage. For example, the point farthest from the print head can be selected for testing, such as Figure 7 At point B shown in the figure, if the trigger voltage can make the corresponding nozzle eject at the corresponding time, and the ejected ink can accurately fall on point B, then based on the trigger voltage triggering the nozzle to eject, the corresponding landing point distances at other positions will also be less than the preset threshold.

[0104] In some embodiments, the ejection timing of each nozzle is determined according to the first printing image, a driving voltage is formed based on the timing of each nozzle and a trigger voltage, and the driving voltage is provided to a printing device to control one or more nozzles to print on a first printing medium moved to a first station, so that a pattern that meets the printing requirements can be formed on the printing surface of the first printing medium.

[0105] In an embodiment of the present application, the controller uses an image acquisition device to acquire an image of the first printing medium moved to the acquisition position to obtain a first image. Based on the first image, the controller determines the deviation posture information of the first printing medium from the target posture, obtains a reference printing image matching the target posture, and transforms the reference printing image based on the deviation posture information to obtain a first printing image matching the first printing medium. Based on the first printing image, the controller controls one or more nozzles of the printing device to print the first printing medium moved to the first station. The controller can first determine the deviation posture information between the first printing medium and the target posture, and then transform the reference printing image matching the target posture based on the deviation posture information, so that the reference printing image is adjusted in posture accordingly to obtain a first printing image matching the first printing medium, so that even if the posture of the first printing medium relative to the target changes, the pattern printed on the first printing medium can be aligned to achieve precise printing.

[0106] At the same time, the transformation processing of the reference printed image matching the target posture is completed by software, which has an extremely fast response speed. Compared with mechanical adjustment, the adjustment speed is faster and mechanical wear is avoided.

[0107] Please refer to Fig.10 , which shows a schematic diagram of a process for determining posture deviation information provided in an embodiment of the present application, wherein the first printing medium is provided with one or more markers.

[0108] like Fig.10As shown, according to the first image, determining the deviation posture information of the first printing medium from the target posture may include steps 1002 to 1006. In this embodiment, the deviation posture information may include deviation posture data between the first posture corresponding to the first printing medium and the target posture.

[0109] Step 1002: Identify each marker in the first image and determine the image position of each marker in the first image.

[0110] It should be noted that the marker may refer to a portion of the first printing medium having a specific shape, color, pattern, texture or other significant features. By setting one or more markers on the first printing medium, when the image acquisition device acquires an image of the first printing medium, a first image containing the markers may be acquired, and the controller identifies each marker in the first image and determines the image position of each marker in the first image.

[0111] In some embodiments, the controller may store target features corresponding to the markers of the first printing medium, and the controller may determine the markers in the first image that match the target features based on the target features corresponding to the markers, and determine the image position of the markers in the first image. In this embodiment, by pre-storing the target features of each marker, the markers that match the target features can be quickly and accurately screened out based on the target features, thereby increasing the speed of determining the posture deviation information, thereby determining the deviation posture information before the first printing medium moves to the first station, realizing the transformation processing of the reference printing image, obtaining the first printing image, and ensuring the printing rate.

[0112] In other embodiments, the first image is input into a trained recognition model, and each marker in the first image is recognized by the recognition model to obtain the image position of the marker in the first image output by the recognition model. It should be noted that the trained recognition model is trained by a training sample set to obtain a trained recognition model, and the training sample set may include multiple sample images containing markers, and the image position of the marker in each sample image in the sample image. The trained recognition model obtained by training the recognition model to be trained by the training sample set can recognize the marker from the first image and locate the image position of the marker in the first image.

[0113] Exemplarily, a sample image is input into the recognition model to be trained for recognition, and the position of the marker output by the recognition model to be trained is obtained. Based on the position of the marker and the image position corresponding to the sample image, it is determined whether the recognition model to be trained meets the conditions for completion of training. If not, the model parameters of the recognition model to be trained are adjusted, and the step of inputting the sample image into the recognition model to be trained for recognition is continued until the recognition model to be trained meets the conditions for completion of training, thereby obtaining a trained recognition model.

[0114] In this embodiment, the marker in the first image is directly identified and located through the recognition model, so that the position of the marker in the first image can be determined efficiently and accurately.

[0115] In some embodiments, when the controller detects that the transfer device moves to the acquisition position, the image acquisition device is triggered to perform image acquisition. If the position of the transfer device is different when the image acquisition device starts to acquire images, even if the posture of the print medium relative to the transfer device remains unchanged, the position of the print medium in the first image acquired by the image acquisition device is different. In this embodiment, when the controller determines that the transfer device moves to the acquisition position, the image acquisition device is triggered to acquire images, which can ensure that the position of the transfer device is the same each time image acquisition starts, thereby ensuring the accuracy of the first posture determined based on the first image, and further ensuring the accuracy of the transformation of the reference print image based on the posture deviation information.

[0116] Step 1004: Determine the first position corresponding to the first printing medium based on the image positions corresponding to the respective markers.

[0117] It should be noted that the first posture may include posture data corresponding to one or more points in the printing surface of the first printing medium, and the first posture corresponding to the first printing medium includes position data and angle data of the first printing medium in the first image.

[0118] In some embodiments, the first printing medium is provided with a first marker and a second marker, and the first position includes first position data and first angle data corresponding to the midpoint between the first marker and the second marker. Determining the first position corresponding to the first printing medium based on the image position corresponding to each marker may include: the controller determines the first position data and first angle data of the midpoint between the first marker and the second marker in the first image according to the image position corresponding to the first marker and the image position corresponding to the second marker.

[0119] For example, if the image position corresponding to the first marker is (x2, y2), and the image position corresponding to the second marker is (x3, y3), then the first position data of the midpoint between the first marker and the second marker in the first image is The first angle data of the midpoint in the first image is

[0120] Step 1006, determining the deviation posture data between the first posture and the target posture.

[0121] It should be noted that the deviation posture data is used to characterize the deviation between the first posture and the target posture, and the deviation posture data may include deviation position data and / or deviation angle data.

[0122] In some embodiments, the first posture includes first position data and first angle data corresponding to the midpoint between the first marker and the second marker, and the target posture includes target position data and target angle data. Determining the deviation posture data between the first posture and the target posture may include: determining the deviation position data between the first position data and the target position data, and determining the deviation angle data between the first angle data and the target angle data.

[0123] It should be noted that the controller can pre-store target position data and target angle data. When the first position data and first angle data corresponding to the midpoint between the first marker and the second marker are determined based on the image positions corresponding to each marker, the difference between the first position data and the target position data can be calculated, and the difference can be used as the deviation position data. The difference between the first angle data and the target angle data can be determined, and the difference can be used as the deviation angle data.

[0124] In some embodiments, the second printing medium includes a first marker and a second marker, and the controller can determine the target position data and target angle data of the midpoint between the first marker and the second marker in the second image according to the image position of the first marker in the second image and the image position of the second marker in the second image. It should be noted that the first marker of the second printing medium matches the first marker of the first printing medium, and the second marker of the second printing medium matches the second marker of the first printing medium. When manufacturing each printing medium, the corresponding first marker and second marker can be formed on the printing medium to achieve positioning. In this embodiment, by storing the target position data and target angle data of the midpoint between the first marker and the second marker in the second image, the deviation posture data between the first posture and the target posture can be determined when the first position data and the first angle data are obtained, thereby reducing the storage amount and calculation amount of the controller.

[0125] In some embodiments, based on the deviation posture information, a reference printed image that matches the target posture is transformed to obtain a first printed image that matches the first posture, which may include: a controller translating the reference printed image based on the deviation position data, and rotating the reference printed image based on the deviation angle data to obtain the first printed image.

[0126] In this embodiment, a first printed image is obtained by translating the reference printed image according to the deviation position data and rotating the reference printed image according to the deviation angle data, so that the posture of the pattern of the obtained first printed image matches the posture of the first printing medium. Based on the first printed image, one or more nozzles of the coating device are controlled to print the first printing medium moved to the first station, so that the position of the pattern printed on the first printing medium is consistent with the position of the pattern obtained by printing the second printing medium moved to the first station based on the reference printed image, so that even if the posture of the first printing medium deviates relative to the second printing medium, the printing accuracy of the first printing medium can be guaranteed.

[0127] In this embodiment, by identifying each marker in the first image, determining the image position of each marker in the first image, and based on each image position, determining the first posture corresponding to the first printing medium, and then determining the deviation posture data between the first posture and the target posture, the accuracy of the determined deviation posture data can be guaranteed, and the printing accuracy of printing according to the first printing image can be guaranteed.

[0128] Please refer to Fig.11 , which shows a flow chart of another process for determining posture deviation information provided by an embodiment of the present application. Fig.11 As shown, determining the deviation posture information of the first printing medium from the target posture according to the first image may include steps 1102 to 1106.

[0129] Step 1102, performing image matching on the first image and the second image corresponding to the target posture to obtain multiple groups of feature point pairs.

[0130] Each set of feature point pairs includes a first feature point in a first image and a second feature point in a second image that matches the first feature point, and the second image is acquired by an image acquisition device.

[0131] In some embodiments, performing image matching between a first image and a second image corresponding to a target posture to obtain multiple sets of feature point pairs may include: a controller extracting a first feature point in the first image and a second feature point in the second image, and performing feature point matching between multiple first feature points and multiple second feature points to obtain multiple sets of feature points. Among them, feature points may include key points and descriptors. Key points refer to the image position of the feature point in the image. The descriptor is usually a vector that describes the information of the pixels around the key point. Feature point matching is performed on feature descriptors. The distance between the two descriptors can reflect the similarity of the two feature points, that is, whether the two feature points are the same. Different distance metrics can be selected according to different descriptors. If it is a floating point type descriptor, its Euclidean distance can be used. If it is a BRIEF (Binary Robust Indenpendent Elementary Features, binary descriptor), its Hamming distance can be used (the Hamming distance between two different binary refers to the number of different bits in the two binary strings).

[0132] In some embodiments, the controller may extract the first feature point in the first image and the second feature point in the second image based on the SIFT algorithm, or the controller may extract the first feature point in the first image and the second feature point in the second image based on the KAZE algorithm. Among them, SIFT (Scale-invariant feature transform) is a machine vision algorithm used to detect and describe local features in images. It looks for extreme points in the spatial scale and extracts their position, scale, and rotation invariants. The KAZE (KAZE Accelerated Segment Test) algorithm is a feature detection method based on nonlinear scale space, with good scale invariance and robustness. It is understandable that the controller can also extract the first feature point in the first image and the second feature point in the second image based on other algorithms, and this embodiment does not limit this.

[0133] Step 1104: Determine the deviation distance between the first feature point and the second feature point of each feature point pair according to the multiple feature point pairs.

[0134] It should be noted that the deviation distance may refer to the distance between the image position of the first feature point in the first image and the image position of the second feature point in the second image. Exemplarily, the coordinates of the first feature point in the first image are (x4, y4), and the coordinates of the second feature point in the second image are (x5, y5). The deviation distance corresponding to the feature point pair includes a first displacement amount △x corresponding to the first direction and a second displacement amount △y corresponding to the second direction, wherein △x=x4-x5, △y=y4-y5.

[0135] Step 1106 , determining deviation posture information of the first printing medium from the target posture according to the deviation distances respectively corresponding to the plurality of groups of feature point pairs.

[0136] It should be noted that the deviation posture information of the first printing medium from the target posture may include deviation posture data between the first posture corresponding to the first printing medium and the target posture.

[0137] In some embodiments, the controller may determine the third displacement amount of the first image relative to the second image in the first direction, and the fourth displacement amount of the first image relative to the second image in the second direction, according to the first displacement amounts and the second displacement amounts corresponding to the plurality of sets of feature point pairs. It should be noted that the plurality of first feature points are evenly distributed in the first image, and the plurality of second feature points are evenly distributed in the second image. Based on the third displacement amount corresponding to the first image and the second image in the first direction, and the fourth displacement amount corresponding to the first image and the second image in the second direction, the reference print image is transformed, and the overall translation deviation and rotation deviation of the reference print image are adjusted to ensure the printing accuracy of the first print image obtained after the transformation.

[0138] Optionally, determining a third displacement of the first image relative to the second image in the first direction and a fourth displacement of the first image relative to the second image in the second direction based on first displacements and second displacements corresponding to multiple groups of feature point pairs may include: calculating an average value of the first displacements corresponding to multiple groups of feature point pairs to obtain a third displacement, and calculating an average value of the second displacements corresponding to multiple groups of feature point pairs to obtain a fourth displacement.

[0139] In this embodiment, the deviation posture information of the first printing medium from the target posture is determined based on the deviation distances corresponding to the multiple groups of feature point pairs of the first image and the second image, and the reference printing image matching the target posture is transformed based on the deviation posture information to obtain a first printing image matching the first printing medium, thereby ensuring the accuracy of the obtained first printing image.

[0140] Please refer to Fig.12, which shows a flow chart of another printing correction method provided in an embodiment of the present application. In this embodiment, the printing surface of the first printing medium includes a curved surface, and the printing system may also include a height acquisition device. The method can be applied to the controller of the printing system.

[0141] like Fig.12 As shown, the printing correction method may include steps 1202 to 1218.

[0142] Step 1202: Use an image acquisition device to acquire an image of the first printing medium moved to the acquisition position to obtain a first image.

[0143] Step 1204: Determine, based on the first image, deviation posture information of the first printing medium relative to the target posture.

[0144] Step 1206: Acquire a reference printed image that matches the target pose.

[0145] Step 1208: transform the reference print image according to the deviation posture information to obtain a first print image that matches the first print medium.

[0146] It should be noted that for the description of steps 1202 to 1208, please refer to the above embodiment, which will not be repeated here.

[0147] Step 1210: Scan the first printing medium moved to the collection position by a height collection device to obtain distance information between the printing surface of the first printing medium and the height collection device.

[0148] It should be noted that the height acquisition device can be used to detect the distance between the printing surface of the first printing medium and the height acquisition device, and the distance information can be used to characterize the distance between the printing surface of the first printing medium and the height acquisition device. The printing system may include one or more height acquisition devices, so that the scanning range of the multiple height acquisition devices along the second direction covers the first printing medium along the second direction to avoid missing the distance between part of the printing surface and the height acquisition device. Optionally, the height acquisition device may include but is not limited to a laser sensor or an ultrasonic sensor.

[0149] Exemplarily, the height acquisition device and the image acquisition device respectively scan the first printing medium moved to the acquisition position, so that the distance information detected by the height acquisition device can be matched with the first image acquired by the image acquisition device, thereby obtaining three-dimensional information corresponding to the printing surface of the first printing medium.

[0150] Exemplarily, the height acquisition device can detect the distance between the printing surface of the first printing medium and the height acquisition device along the third direction, wherein the third direction is perpendicular to the first direction and the second direction. Exemplarily, the height acquisition device can include a laser sensor, which can emit laser along the third direction to detect the distance between the printing surface and the height acquisition device along the third direction.

[0151] Step 1212: Determine the height information between the printing surface and the carrying surface of the transfer device according to the distance information.

[0152] Step 1214: Determine curvature information of the printing surface of the first printing medium according to the height information.

[0153] It should be noted that the bearing surface of the transfer device may refer to the surface of the transfer device that contacts the first printing medium, and the height information may be used to characterize the distance between the printing surface of the first printing medium and the bearing surface of the transfer device. The height information may include height data corresponding to a plurality of points in the printing surface of the first printing medium, and the height data corresponding to each point includes the distance between the point and the bearing surface. The controller may pre-store the distance between the height acquisition device and the bearing surface, so as to determine the height information between the printing surface of the printing medium and the bearing surface of the transfer device based on the distance information and the distance between the height acquisition device and the bearing surface.

[0154] It should be noted that the curvature information can be used to characterize the curvature of the printing surface of the first printing medium. The curvature information can include the curvatures corresponding to the multiple points of the printing surface of the first printing medium. The controller can determine the curvatures corresponding to the multiple points of the printing surface of the first printing medium according to the height data corresponding to the multiple points of the printing surface.

[0155] In some embodiments, the height data corresponding to each point in the printing surface includes a first distance between the point and the supporting surface, the curvature information includes the curvatures corresponding to the multiple points on the printing surface, and determining the curvature information of the printing surface of the first printing medium based on the height information may include: a controller determines the three-dimensional coordinates corresponding to the multiple points on the printing surface based on the image positions of the multiple points on the printing surface in the first image and the first distances corresponding to the multiple points, determines the surface function corresponding to the printing surface based on the three-dimensional coordinates corresponding to the multiple points, and determines the curvatures corresponding to the multiple points on the printing surface based on the surface function.

[0156] Step 1216: adjust the number of pixels included in the first printed image according to the curvature information to obtain a second printed image.

[0157] It should be noted that the greater the curvature, the greater the curvature of the printing surface, and the greater the difference between the length of the printing surface and the length of the projection of the printing surface in the first direction. Fig.13, the length of line segment AB in the first direction X is L, the length of line segment BC in the first direction X is also L, and the length of line segment AB is greater than the length of line segment BC. The A' pixel point, B' pixel point and C' pixel point of the first printed image correspond to the A point, B point and C point of the first printed medium respectively. In the first printed image, the spacing between the A' pixel point and the B' pixel point, and the spacing between the B' pixel point and the C' pixel point are both L, but in the pattern printed on the first printed medium, the distance between the A point and the B point, and the spacing between the B point and the C point are obviously different, resulting in different resolutions of the printed surface of the first printed medium. In this embodiment, the number of pixels contained in the first printed image is adjusted according to the curvature information, thereby adjusting the ejection frequency of the nozzle, so that the ejection frequency matches the curvature information, reducing the phenomenon that the distance between each printed point of the pattern caused by the curved surface changes, ensuring the resolution of the pattern on the printed surface, and ensuring the printing quality. For example, if a printing point D is added between point A and point B, the distance between point A and point D, the distance between point D and point B, and the distance between point B and point C can be made equal, so that the resolution of the pattern of the first curved medium is uniform, and a printing point is formed at point D of the printing medium by adding D' pixel point in the first printed image.

[0158] Exemplarily, the greater the curvature of the printing surface indicated by the curvature information, the more pixels of the obtained second printing image. It should be noted that when the curvature of the printing surface is greater, the number of pixels added in the first printing image increases, so that according to the second printing image, the spraying frequency of one or more nozzles of the printing device is controlled to increase, so that the resolution of the pattern printed on the first printing medium is uniform.

[0159] Exemplarily, if the curvature of the printing surface indicated by the curvature information is less than or equal to the curvature threshold, the number of pixels included in the first printing image may not be adjusted. It should be noted that the pixel threshold can be used to measure whether the printing surface is close to a plane. If the curvature is greater than the curvature threshold, the printing surface is considered to be a curved surface. If the curvature is less than or equal to the curvature threshold, the printing surface is considered to be close to a plane. When the curvature is less than or equal to the curvature threshold, the number of pixels included in the first printing image is not adjusted. While ensuring that the spacing between the printing points of the printing pattern is uniform, the amount of calculation of the controller can be reduced.

[0160] In some embodiments, adjusting the number of pixels included in the first printed image according to the curvature information to obtain the second printed image may include: the controller performs an interpolation operation on the first printed image according to the curvature information to increase the number of pixels included in the first printed image to obtain the second printed image. It should be noted that the interpolation operation refers to calculating new pixel values ​​based on the values ​​of existing pixels to fill the blank areas in the first printed image. Through the interpolation operation, new pixels can be inserted between rows or columns of the first printed image, so that the pixels of the printed pattern in the second printed image are denser. In this embodiment, by inserting new pixels, the ejection frequency of the nozzle is increased, thereby increasing the number of printed dots on the printing surface, thereby reducing the problem of uneven ink dot spacing caused by curvature and improving printing quality.

[0161] Step 1218: Control one or more nozzles of the printing device according to the second printing image to print on the first printing medium moved to the first station.

[0162] It should be noted that the number of pixels of the adjusted second printed image changes. As the number of pixels increases, the printing frequency of the print head increases. That is, relative to printing the first printed image, the spacing between the print dots of the first printing medium decreases, making the resolution of the curved printed surface uniform.

[0163] In this embodiment, the controller adjusts the number of pixels included in the first printed image according to the curvature information to obtain the second printed image, so that the printing frequency of the nozzle (the frequency of ejecting ink droplets) matches the curvature information, ensuring that the resolution of the printed pattern on the first printing medium based on the second printed image is similar, thereby ensuring the printing quality.

[0164] Please refer to Fig.14 , which shows a schematic diagram of a process for obtaining a second printed image provided by an embodiment of the present application. The height information includes height data corresponding to a plurality of points on the printing surface of the first printing medium. Fig.14 As shown, adjusting the number of pixels included in the first printed image according to the curvature information to obtain the second printed image may include steps 1402 to 1406.

[0165] Step 1402: Divide the first printed image into a plurality of image regions according to the curvature information.

[0166] It should be noted that the printing surface includes medium areas corresponding to a plurality of image areas one by one, and the image areas are used to control the printing device to print on the corresponding medium areas.

[0167] Exemplarily, the multiple pixel points contained in the image area are used to indicate the printing parameters corresponding to the multiple points in the medium area corresponding to the image area, such as the color of the printed points and whether it is necessary to form ink droplets in the points (that is, whether printing is required), etc. The denser the pixel points in the image area indicating the need for printing, the denser the printing points in the medium area corresponding to the image area.

[0168] Exemplarily, among multiple points in the medium area corresponding to the same image area, the difference between the corresponding maximum curvature and the minimum curvature is less than the curvature threshold, that is, the difference in curvature corresponding to any two points in the same medium area is very small, thereby ensuring that the number of pixels contained in the adjusted image area is adapted to the curvature of the medium area, ensuring that the resolution of the printed pattern meets the requirements.

[0169] In some embodiments, the printing surface of the first printing medium is divided into a plurality of medium areas according to the curvature information, and the first printing image is divided into a plurality of image areas corresponding to the plurality of medium areas one by one according to the correspondence between the printing surface and the first printing image.

[0170] Step 1404: Determine the adjustment ratio corresponding to each image area according to the height change information corresponding to the printing surface corresponding to each image area.

[0171] It should be noted that the height change information corresponding to the print surface corresponding to the image area may refer to the height change information of the medium area corresponding to the image area, and the height change information of the medium area may be used to describe the change trend of the height data of multiple points in the medium area, or the height difference, etc. Optionally, the height change information of the medium area may include but is not limited to the slope corresponding to the medium area, the curvature corresponding to the medium area, the height gradient corresponding to the medium area, etc. The adjustment ratio corresponding to the image area may refer to the ratio between the number of pixel points indicating that a printing operation needs to be performed in the image area in the second printed image and the number of pixel points indicating that a printing operation needs to be performed in the image area in the first printed image.

[0172] In some embodiments, the height information includes height data corresponding to a plurality of points in the print surface, and the height change information corresponding to the print surface corresponding to the image area includes the slope of the print surface corresponding to the image area. The controller can determine the highest point and the lowest point of the print surface corresponding to the first image area, and determine the slope of the print surface corresponding to the first image area according to the image position in the first image area corresponding to the highest point, the height data corresponding to the highest point, the image position in the first image area corresponding to the lowest point, and the height data corresponding to the lowest point.

[0173] It should be noted that the first image area is any one of the multiple image areas, the highest point is the point with the largest height data in the printing surface corresponding to the first image area, and the lowest point is the point with the smallest height data in the printing surface corresponding to the first image area, that is, the highest point is the point in the medium area corresponding to the first image area that is closest to the height acquisition device, and the lowest point is the point in the medium area corresponding to the first image area that is farthest from the height acquisition device. The height data and the image position of the first image area both correspond to points on the medium area. If the slope of the medium area is greater, more printing points should fall on the medium area.

[0174] In some embodiments, the slope of the printing surface may include the slope of the printing surface along the first direction. Determining the slope of the printing surface corresponding to the first image area according to the image position in the first image area corresponding to the highest point, the height data corresponding to the highest point, the image position in the first image area corresponding to the lowest point, and the height data corresponding to the lowest point may include: the controller determines a first value in the first image position and a second value in the second image position, calculates the position difference between the first value and the second value, calculates the height difference between the height data corresponding to the highest point and the height data corresponding to the lowest point, calculates the ratio of the height difference to the position difference, and determines the ratio as the slope of the medium area corresponding to the first image area. The first image position is the image position in the first image area corresponding to the highest point, the second image position is the image position in the first image area corresponding to the lowest point, the first value is the coordinate value in the first image position corresponding to the first direction, and the second value is the coordinate value in the second image position corresponding to the first direction.

[0175] In some embodiments, determining the adjustment ratio corresponding to each image area according to the height change information corresponding to the printing surface corresponding to each image area may include: the controller determines the adjustment ratio corresponding to each image area according to the slope of the printing surface corresponding to each image area. For example, the adjustment ratio is in, is the slope of the printing surface corresponding to the image area, △H is the height difference between the height data corresponding to the highest point and the height data corresponding to the lowest point in the first image area, and △L is the position difference between the first position and the second position in the first image area.

[0176] Step 1406, adjusting the number of pixels included in each image area according to the adjustment ratio corresponding to each image area, to obtain a second printed image.

[0177] In some embodiments, the transfer device carries the first printing medium and drives the first printing medium to move at a uniform speed along the first direction, and adjusts the number of pixels contained in each image area according to the adjustment ratio corresponding to each image area to obtain the second printed image, which may include: the controller interpolates each image area in the first printed image along the first direction according to the adjustment ratio corresponding to each image area to obtain the second printed image. Among them, the ratio between the number of pixels in each image area in the second printed image along the first direction and the number of pixels in the corresponding image area in the first printed image along the first direction is the adjustment ratio corresponding to the corresponding image area, that is, the controller interpolates the second image area along the first direction according to the adjustment ratio corresponding to the second image area to obtain the second printed image, and the ratio between the number of pixels in the second image area in the second printed image along the first direction and the number of pixels in the second image area in the first printed image along the first direction is the adjustment ratio corresponding to the second image area, and the second image area is any one of the multiple image areas.

[0178] It should be noted that the transfer device moves at a uniform speed along the first direction. In order to ensure the quality of the ink droplets of the printing points, the speed of the transfer device is generally not very fast. Therefore, if the printing surface of the first printing medium is a curve along the first direction, the spacing between the printing points will be unequal. In this embodiment, by adjusting the number of pixels contained in each image area, the frequency of the print head printing to the medium area corresponding to the image area is adjusted, thereby ensuring that the spacing between two printing points is uniform and the printing resolution is guaranteed.

[0179] Exemplarily, the spacing between two adjacent nozzles along the second direction in the print head is less than or equal to the distance threshold. It should be noted that when the spacing between two adjacent nozzles is less than or equal to the distance threshold, it can be considered that the spacing between the two adjacent nozzles is very small, so even if the printing surface is a curve along the second direction, it can be ensured that the spacing difference of the printed points along the second direction is very small, and the curvature has little effect on the printed points, thereby ensuring the printing accuracy.

[0180] In this embodiment, the number of pixels of the second printed image matches the curvature of the surface of the first printing medium. The first printing medium including the curved surface is partitioned according to the curvature and the resolution of the printed image corresponding to the moving direction is adjusted accordingly. That is, the printing frequencies corresponding to different curvatures are different, so that the intervals between ink dots of surfaces with different curvatures are close, thereby ensuring the printing quality.

[0181] In this embodiment, the first printed image is divided into multiple image areas based on the curvature information, and the adjustment ratio corresponding to each image area is determined based on the height change information corresponding to the printing surface corresponding to each image area, that is, the printing frequency of the nozzles corresponding to the medium areas with different curvatures is different, so that the intervals between the printing points in the printing surfaces with different curvatures are uniform, thereby ensuring the printing resolution.

[0182] Please refer to Fig.15 , which shows a schematic diagram of the structure of a printing correction device disclosed in an embodiment of the present application. The device can be applied to a controller of a printing system. The printing system also includes an image acquisition device, a transfer device and a printing device. The transfer device is used to carry a first printing medium, and first transfer the first printing medium to a collection position corresponding to the image acquisition device, and then transfer the first printing medium to a first station corresponding to the printing device. Fig.15 As shown, the printing deviation correction device 1500 may include an image acquisition module 1510 , a first determination module 1520 , an image acquisition module 1530 , an image transformation module 1540 and a printing control module 1550 .

[0183] The image acquisition module 1510 is used to acquire an image of the first printing medium moved to the acquisition position through an image acquisition device to obtain a first image. The first determination module 1520 is used to determine the deviation posture information of the first printing medium from the target posture according to the first image. The image acquisition module 1530 is used to acquire a reference printing image matching the target posture. The image transformation module 1540 is used to transform the reference printing image according to the deviation posture information to obtain a first printing image matching the first printing medium. The printing control module 1550 is used to control one or more nozzles of the printing device according to the first printing image to print the first printing medium moved to the first station.

[0184] In some embodiments, the first printing medium is provided with one or more markers, and the one or more markers are provided on the printing surface of the first printing medium so that the image acquisition device can acquire the markers. The deviation posture information includes deviation posture data between the first posture corresponding to the first printing medium and the target posture. The first determination module 1520 includes an identification unit, a first determination unit and a second determination unit. The identification unit is used to identify each marker in the first image and determine the image position of each marker in the first image. The first determination unit is used to determine the first posture corresponding to the first printing medium based on the image position corresponding to each marker. The second determination unit is used to determine the deviation posture data between the first posture and the target posture.

[0185] In some embodiments, the first printing medium is provided with a first marker and a second marker, the first position includes first position data and first angle data corresponding to the midpoint between the first marker and the second marker, and the target position includes target position data and target angle data corresponding to the midpoint. The second determining unit includes a first determining subunit and a second determining subunit. The first determining subunit is used to determine the deviation position data between the first position data and the target position data. The second determining subunit is used to determine the deviation angle data between the first angle data and the target angle data.

[0186] In some embodiments, the first determination module 1520 includes a matching unit, a third determination unit, and a fourth determination unit. The matching unit is used to perform image matching between the first image and the second image corresponding to the target posture to obtain multiple groups of feature point pairs, each group of feature point pairs includes a first feature point in the first image, and a second feature point in the second image that matches the first feature point, and the second image is acquired by an image acquisition device. The third determination unit is used to determine the deviation distance between the first feature point and the second feature point of each group of feature point pairs based on the multiple groups of feature point pairs. The fourth determination unit is used to determine the deviation posture information of the first printing medium from the target posture based on the deviation distances corresponding to the multiple groups of feature point pairs.

[0187] In some embodiments, the printing surface of the first printing medium includes a curved surface, and the printing system further includes a height acquisition device. The printing correction device 1500 further includes a height acquisition module, a second determination module, and a third determination module. The printing control module 1550 includes an adjustment unit and a control unit. The height acquisition module is used to scan the first printing medium moved to the acquisition position through the height acquisition device to obtain the distance information between the printing surface of the first printing medium and the height acquisition device. The second determination module is used to determine the height information between the printing surface and the bearing surface of the transfer device according to the distance information. The third determination module is used to determine the curvature information of the printing surface of the first printing medium according to the height information. The adjustment unit is used to adjust the number of pixels contained in the first printing image according to the curvature information to obtain a second printing image. The control unit is used to control one or more nozzles of the printing device according to the second printing image to print the first printing medium moved to the first station.

[0188] In some embodiments, the height information includes height data corresponding to a plurality of points in the print surface of the first print medium. The adjustment unit includes a division subunit, a third determination subunit, and an adjustment subunit. The division subunit is used to divide the first print image into a plurality of image areas according to the curvature information. The third determination subunit is used to determine the adjustment ratio corresponding to each image area according to the height change information corresponding to the print surface corresponding to each image area. The adjustment subunit is used to adjust the number of pixels contained in each image area according to the adjustment ratio corresponding to each image area to obtain a second print image.

[0189] In some embodiments, the height information includes height data corresponding to multiple points in the print surface; the height change information corresponding to the print surface corresponding to the image area includes the slope of the print surface corresponding to the image area. The print correction device 1500 also includes a fourth determination module and a fifth determination module. The fourth determination module is used to determine the highest point and the lowest point of the print surface corresponding to the first image area; wherein the highest point is the point with the largest height data in the print surface corresponding to the first image area, and the lowest point is the point with the smallest height data in the print surface corresponding to the first image area; the first image area is any one of the multiple image areas. The fifth determination module is used to determine the slope of the print surface corresponding to the first image area according to the image position in the first image area corresponding to the highest point, the height data corresponding to the highest point, the image position in the first image area corresponding to the lowest point, and the height data corresponding to the lowest point.

[0190] In an embodiment of the present application, the controller may first determine the deviation posture information between the first printing medium and the target posture, and then transform the reference printed image that matches the target posture according to the deviation posture information, so that the reference printed image is adjusted accordingly to obtain a first printed image that matches the first printing medium, so that even if the posture of the first printing medium relative to the target changes, the pattern printed on the first printing medium can be aligned to achieve precise printing.

[0191] At the same time, the transformation processing of the reference printed image matching the target posture is completed by software, which has an extremely fast response speed. Compared with mechanical adjustment, the adjustment speed is faster and mechanical wear is avoided.

[0192] The embodiment of the present application also provides a printing system, which may include an image acquisition device, a printing device, a transfer device and a controller. The transfer device is used to carry a first printing medium, and first transfer the first printing medium to a collection position corresponding to the image acquisition device, and then transfer the first printing medium to a first station corresponding to the printing device.

[0193] Please refer to Fig.16, which shows a schematic diagram of the structure of a controller of a printing system disclosed in an embodiment of the present application.

[0194] like Fig.16 As shown, the controller 1600 may include:

[0195] A memory 1610 storing executable program codes;

[0196] a processor 1620 coupled to the memory 1610;

[0197] The processor 1620 calls the executable program code stored in the memory 1610 to execute any one of the printing deviation correction methods disclosed in the embodiments of the present application.

[0198] An embodiment of the present application discloses a computer-readable storage medium storing a computer program, wherein when the computer program is executed by the processor, the processor implements any one of the printing deviation correction methods disclosed in the embodiment of the present application.

[0199] It should be understood that the "one embodiment" or "an embodiment" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. 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. Those skilled in the art should also be aware that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily required for the present application.

[0200] In the various embodiments of the present application, it should be understood that the size of the serial numbers of the above-mentioned processes does not necessarily mean the order of execution. The execution order of each 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 application.

[0201] The units described above as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on 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.

[0202] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0203] If the above-mentioned integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-accessible memory. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product, which is stored in a memory and includes several requests for a computer device (which can be a personal computer, a server or a network device, etc., specifically a processor in a computer device) to perform some or all of the steps of the above-mentioned methods of various embodiments of the present application.

[0204] Those skilled in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable storage medium, and the storage medium includes a read-only memory (ROM), a random access memory (RAM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), a one-time programmable read-only memory (OTPROM), an electronically erasable rewritable read-only memory (EEPROM), a compact disc (CD-ROM) or other optical disc storage, magnetic disk storage, magnetic tape storage, or any other computer-readable medium that can be used to carry or store data.

[0205] The above is a detailed introduction to a printing correction method, device, printing system and computer-readable storage medium disclosed in the embodiments of the present application. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core ideas of the present application. At the same time, for those of ordinary skill in the art, according to the ideas of the present application, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A printing correction method, characterized in that: A controller applied to a printing system, wherein the printing system further comprises an image acquisition device, a transfer device and a printing device, wherein the transfer device is used to carry a first printing medium and first transfer the first printing medium to a collection position corresponding to the image acquisition device, and then transfer the first printing medium to a first station corresponding to the printing device; the method comprises: Capturing an image of the first printing medium moved to the acquisition position by the image acquisition device to obtain a first image; Determining deviation posture information of the first printing medium from a target posture according to the first image; Acquire a reference printed image matching the target pose; Transform the reference print image according to the deviation posture information to obtain a first print image matching the first print medium; According to the first printing image, one or more nozzles of the printing device are controlled to print on the first printing medium moved to the first station.

2. The method according to claim 1, characterized in that The first printing medium is provided with one or more markers, and the deviation posture information includes deviation posture data between a first posture corresponding to the first printing medium and a target posture; The step of determining, according to the first image, the deviation posture information of the first printing medium from the target posture includes: Identify each marker in the first image, and determine the image position of each marker in the first image; Determining a first position corresponding to the first printing medium based on the image positions corresponding to the respective markers; Determine deviation pose data between the first pose and the target pose.

3. The method according to claim 2, characterized in that The first printing medium is provided with a first marker and a second marker, the first posture includes first position data and first angle data corresponding to a midpoint between the first marker and the second marker, and the target posture includes target position data and target angle data corresponding to the midpoint; The determining of deviation posture data between the first posture and the target posture comprises: determining deviation position data between the first position data and the target position data; Determine a deviation angle data between the first angle data and the target angle data.

4. The method according to claim 1, characterized in that: The step of determining, according to the first image, the deviation posture information of the first printing medium from the target posture includes: Performing image matching between the first image and a second image corresponding to the target posture to obtain a plurality of feature point pairs, each feature point pair comprising a first feature point in the first image and a second feature point in the second image that matches the first feature point; the second image is acquired by an image acquisition device; Determine, based on the plurality of feature point pairs, a deviation distance between a first feature point and a second feature point of each feature point pair; Determine deviation posture information of the first printing medium deviating from the target posture according to the deviation distances respectively corresponding to the plurality of groups of feature point pairs.

5. The method according to claim 1, characterized in that The printing surface of the first printing medium includes a curved surface, and the printing system further includes a height acquisition device; the method further includes: Scanning the first printing medium moved to the acquisition position by the height acquisition device to obtain distance information between the printing surface of the first printing medium and the height acquisition device; Determine the height information between the printing surface and the carrying surface of the transfer device according to the distance information; Determining curvature information of a printing surface of the first printing medium according to the height information; The step of controlling one or more nozzles of the printing device according to the first printing image to print the first printing medium moved to the first station includes: adjusting the number of pixels included in the first printed image according to the curvature information to obtain a second printed image; According to the second printing image, one or more nozzles of the printing device are controlled to print on the first printing medium moved to the first station.

6. The method according to claim 5, characterized in that The step of adjusting the number of pixels included in the first printed image according to the curvature information to obtain a second printed image includes: dividing the first printed image into a plurality of image regions according to the curvature information; Determining the adjustment ratio corresponding to each of the image areas according to the height change information corresponding to the printing surface corresponding to each of the image areas; According to the adjustment ratio corresponding to each of the image areas, the number of pixels included in each of the image areas is adjusted to obtain a second printed image.

7. The method according to claim 6, characterized in that The height information includes height data corresponding to a plurality of points in the printing surface; the height change information corresponding to the printing surface corresponding to the image area includes the slope of the printing surface corresponding to the image area; the method further includes: Determine the highest point and the lowest point of the printing surface corresponding to the first image area; wherein the highest point is the point with the largest height data in the printing surface corresponding to the first image area, and the lowest point is the point with the smallest height data in the printing surface corresponding to the first image area; the first image area is any one of the multiple image areas; The slope of the printing surface corresponding to the first image area is determined based on the image position in the first image area corresponding to the highest point, the height data corresponding to the highest point, the image position in the first image area corresponding to the lowest point, and the height data corresponding to the lowest point.

8. A printing correction device, characterized in that: A controller applied to a printing system, wherein the printing system further comprises an image acquisition device, a transfer device and a printing device, wherein the transfer device is used to carry a first printing medium and first transfer the first printing medium to a collection position corresponding to the image acquisition device, and then transfer the first printing medium to a first station corresponding to the printing device; The printing deviation correction device comprises: An image acquisition module, configured to acquire an image of the first printing medium moved to the acquisition position through the image acquisition device to obtain a first image; A first determining module, configured to determine, based on the first image, deviation posture information of the first printing medium from a target posture; An image acquisition module, used to acquire a reference printed image matching the target pose; an image transformation module, configured to transform the reference print image according to the deviation posture information to obtain a first print image matching the first print medium; and The printing control module is used to control one or more nozzles of the printing device according to the first printing image to print the first printing medium moved to the first station.

9. A printing system, characterized in that: include: Image acquisition device; Printing device; A transfer device, used to carry a first printing medium, and first transfer the first printing medium to a collection position corresponding to the image collection device, and then transfer the first printing medium to a first station corresponding to the printing device; and a controller, including a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor implements the method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 7 is implemented.

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