A sheet splicing and alignment system and alignment method based on a dual-CCD sensor

Abstract

The present invention discloses a sheet splicing and alignment system and an alignment method based on a dual-CCD sensor. The sheet splicing and alignment system includes a control module, an actuator, and two linear CCD sensor modules. The actuator includes a moving platform for placing a first sheet and a driving unit for driving the moving platform to move in the Y direction perpendicular to the X direction. The two linear CCD sensor modules are respectively communicatively connected to the control module and are arranged side by side in the X direction. The control module is communicatively connected to the driving unit and is used to control the driving unit to drive the moving platform to move to a target position according to the signals collected by the two linear CCD sensor modules. The present invention can effectively identify other target features such as printed lines and patterns in addition to the edge line features of the sheet, has a wider application range, and can effectively improve the alignment accuracy of the target features during the splicing process.

Description

Technical Field

[0001] The present invention relates to the technical field of sheet splicing, and in particular to a sheet splicing alignment system and alignment method based on a dual CCD sensor. Background Art

[0002] For occasions where sheet splicing is required, the positions of two sheets may shift during the movement to the splicing position. Therefore, before splicing, it is necessary to align the two sheets to be spliced through a sheet splicing alignment system.

[0003] Currently, in a sheet splicing alignment system, most use optoelectronic sensors (such as a laser sensor composed of a laser emitter and a laser receiver) to detect the position deviation between the two sheets to be spliced. However, optoelectronic sensors can only detect the edges of the sheets and are helpless when other features (such as printed lines or patterns on the sheets) need to be aligned during splicing; moreover, the detection range of optoelectronic sensors is relatively narrow. In the case where the position deviation of the two sheets to be spliced is large, it is easy to lose features and fail to detect the edges of the sheets. Therefore, manual intervention is often required to adjust the positions of the sheets. Summary of the Invention

[0004] The present invention aims to at least solve the above technical problems existing in the prior art, and particularly innovatively provides a sheet splicing alignment system and alignment method based on a dual CCD sensor, effectively solving the problems in the prior art that optoelectronic sensors can only detect the edges of sheets, have poor applicability, and require high professional qualities of operators.

[0005] To achieve the above object of the present invention, according to the first aspect of the present invention, a sheet splicing alignment system based on a dual CCD sensor is provided for aligning corresponding target features of a first sheet and a second sheet to be spliced placed side by side in the X direction.

[0006] The sheet splicing alignment system includes a control module, an actuator, and two linear CCD sensor modules, wherein

[0007] The actuator includes a moving platform for placing the first sheet and a driving unit for driving the moving platform to move in the Y direction perpendicular to the X direction;

[0008] The two linear CCD sensor modules are respectively communicatively connected to the control module, and the two linear CCD sensor modules are arranged side by side along the X direction. One of the linear CCD sensor modules is used to collect a first image of a first target area corresponding to the first sheet, and determine the position information of a first target feature in the first image based on image recognition. The other linear CCD sensor module is used to collect a second image of a second target area corresponding to the second sheet, and determine the position information of a second target feature in the second image based on image recognition. Wherein, the first target feature and the second target feature are features located on the first sheet and the second sheet respectively, and need to be aligned when the first sheet and the second sheet are spliced;

[0009] The control module is communicatively connected to the driving unit. The control module is configured to calculate the moving direction and moving distance of the moving platform according to the position information of the first target feature and the position information of the second target feature, and generate a driving control signal according to the calculated moving direction and moving distance of the moving platform. Wherein, the driving control signal is used to control the driving unit to drive the moving platform to move to a target position so that the first target feature and the second target feature are aligned.

[0010] Preferably, the photosensitive elements of the two linear CCD sensor modules are all arranged along the Y direction, and the connection line between the photosensitive elements at the central positions of the two linear CCD sensor modules is parallel to the X direction.

[0011] Preferably, the linear CCD sensor module includes an LCD touch screen, and the LCD touch screen is used to display the collected image and receive user interaction operations to mark the target feature on the collected image.

[0012] Preferably,

[0013] The determining the position information of the first target feature in the first image based on image recognition includes:

[0014] Calculating a first preselected feature set of each first preselected feature in the first image with a chromaticity value jump greater than a preset chromaticity threshold based on a difference algorithm and a fast Fourier transform;

[0015] Comparing the chromaticity values of the preselected features in the first preselected feature set with the chromaticity values of the pre-marked target features, and determining the first target feature according to the comparison result;

[0016] Obtaining the position information of the first target feature based on the specific position of the pixel points corresponding to the first target feature in the first image and the mapping relationship between the specific positions of the pixel points in the first image and the position coordinates of the pixel points in the imaging area of the linear CCD sensor module;

[0017] The determination of the position information of the second target feature in the second image based on image recognition includes:

[0018] Calculating each second preselected feature with a chromaticity value jump greater than a preset chromaticity threshold in the second image based on the differential algorithm and the fast Fourier transform to obtain a second preselected feature set;

[0019] Comparing the chromaticity values of the preselected features in the second preselected feature set with the chromaticity values of the pre-marked target features, and determining the second target feature according to the comparison result;

[0020] Based on the specific position of the pixel points corresponding to the second target feature in the second image, and the mapping relationship between the specific positions of each pixel point in the second image and the position coordinates of each pixel point in the imaging area of the linear array CCD sensor module, the position information of the second target feature is obtained.

[0021] Preferably, the driving unit includes a driving motor, a driving gear, a driven gear and a lead screw pair. The signal input end of the driving motor is connected to the control module. The output shaft of the driving motor is fixedly connected to the driving gear. The driving gear meshes with the driven gear. The driven gear is fixedly connected to the driving end of the lead screw of the lead screw pair. The nut of the lead screw pair is connected to the moving platform.

[0022] Preferably, the calculation of the moving direction and moving distance of the moving platform according to the position information of the first target feature and the position information of the second target feature includes:

[0023] Obtaining the position of the pixel points corresponding to the first target feature according to the position information of the first target feature, the detection range of the linear array CCD sensor module and the resolution of the linear array CCD sensor module;

[0024] Obtaining the position of the pixel points corresponding to the second target feature according to the position information of the second target feature, the detection range of the linear array CCD sensor module and the resolution of the linear array CCD sensor module;

[0025] Obtaining the moving direction and moving distance of the moving platform according to the position of the pixel points corresponding to the first target feature and the position of the pixel points corresponding to the second target feature.

[0026] Preferably, the generation of the drive control signal according to the calculated moving direction and moving distance of the moving platform includes:

[0027] Calculating the rotation direction and the number of turns to be rotated of the driving motor according to the calculated moving direction, moving distance of the moving platform and the transmission ratio between the driving gear and the transmission gear;

[0028] Calculate the number of Hall pulses required to drive the drive motor based on the calculated number of turns the drive motor needs to rotate and the number of Hall pulses required for the drive motor to rotate one circle.

[0029] Generate the drive control signal based on the calculated number of Hall pulses required to drive the drive motor and the rotation direction of the drive motor.

[0030] Preferably, the linear array CCD sensor module further includes a monochrome CCD chip, a main control MCU, and an RGB backlight module, and the monochrome CCD chip and the RGB backlight module are respectively connected to the main control MCU.

[0031] According to the second aspect of the present invention, the present invention also provides a method for sheet splicing and alignment based on a dual CCD sensor, applying the sheet splicing and alignment system based on a dual CCD sensor according to any one of the above first aspects. The method includes the following steps:

[0032] S1, Adjust the installation positions of the two linear array CCD sensor modules so that the photosensitive elements of the two linear array CCD sensor modules are arranged along the Y direction, and the connection line between the photosensitive elements at the central positions of the two linear array CCD sensor modules is parallel to the X direction.

[0033] S2, Initialize the sheet splicing and alignment system.

[0034] S3, Place the first sheet and the second sheet at the position to be spliced, so that the corresponding target features of the first sheet and the second sheet are aligned, and the target features on the first sheet and the second sheet are respectively facing the central points of the two linear array CCD sensor modules.

[0035] S4, Collect images of the first sheet and the second sheet through the two linear array CCD sensor modules respectively, and mark the target features on the images collected by the two linear array CCD sensor modules respectively.

[0036] S5, Start the sheet splicing and alignment system to align the first sheet and the second sheet to be spliced through the sheet splicing and alignment system.

[0037] Preferably, the alignment of the first sheet and the second sheet to be spliced through the sheet splicing and alignment system includes:

[0038] Collect a first image of a first target area corresponding to the first sheet through one of the linear CCD sensor modules, determine the position information of a first target feature in the first image based on image recognition, collect a second image of a second target area corresponding to the second sheet through the other linear CCD sensor module, and determine the position information of a second target feature in the second image based on image recognition;

[0039] The control module calculates the moving direction and moving distance of the mobile platform according to the position information of the first target feature and the position information of the second target feature, and generates a drive control signal according to the calculated moving direction and moving distance of the mobile platform;

[0040] The drive unit drives the mobile platform to move to a target position based on the drive control signal, so that the first target feature and the second target feature are aligned.

[0041] As can be seen from the above solution, the present invention provides a sheet splicing and alignment system and alignment method based on a dual CCD sensor. By using two side-by-side CCD sensors to respectively detect the target features of two sheets to be spliced, it can effectively identify other target features such as printed lines and patterns in addition to the edge line features of the sheets. It can be applied to the alignment and splicing of two sheets with more types of target features and the alignment and splicing of two sheets with larger position deviations, with a wider application range, effectively improving the alignment accuracy of target features during the splicing process, and effectively solving the problem in the prior art that an optoelectronic sensor can only detect the edges of sheets, and due to the narrow detection range of the optoelectronic sensor, it is easy to fail to detect the edges of sheets when the position deviation between the two sheets to be spliced is large, and the applicability is poor.

[0042] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0044] Figure 1 is a schematic structural diagram of a sheet splicing and alignment system based on a dual CCD sensor in a preferred embodiment of the present invention;

[0045] Figure 2 is a circuit schematic diagram of a linear CCD sensor module in a preferred embodiment of the invention;

[0046] Figure 3 is a circuit schematic diagram of a control module in a preferred embodiment of the present invention;

[0047] Figure 4 It is a schematic flow chart of a sheet splicing and alignment method based on a dual CCD sensor in a preferred embodiment of the present invention. Specific embodiments

[0048] Hereinafter, exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure can be more thoroughly understood and the scope of the present disclosure can be fully conveyed to those skilled in the art.

[0049] Those skilled in the art of the present technology can understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the general understanding of those of ordinary skill in the art to which the present invention belongs. It should also be understood that terms such as those defined in a general dictionary should be understood to have a meaning consistent with the meaning in the context of the prior art, and will not be interpreted in an idealized or overly formal sense unless specifically defined.

[0050] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present invention.

[0051] In the description of the present invention, unless otherwise specified and defined, it should be noted that the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the communication inside two elements. It can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0052] As Figure 1 shown, the present invention provides a sheet splicing and alignment system based on a dual CCD sensor, which is used to align the corresponding target features of a first sheet 100 and a second sheet 200 to be spliced and placed side by side along the X direction (the direction indicated by the arrow on the first sheet 100 in FIG. 1). The system includes a control module 1, an actuator 2, and two linear array CCD sensor modules 3.

[0053] The actuator 2 includes a moving platform 21 for placing the first sheet 100 and a driving unit 22 for driving the moving platform 21 to move in the Y direction perpendicular to the X direction (such as Figure 1 the direction indicated by the double-headed arrow on the moving platform 21).

[0054] Two linear CCD sensor modules 3 are respectively communicatively connected to the control module 1 and are arranged side by side in the X direction. One of the linear CCD sensor modules 3 is used to collect a first image of a first target area corresponding to the first sheet 100 and determine the position information of the first target feature in the first image based on image recognition. The other linear CCD sensor module 3 is used to collect a second image of a second target area corresponding to the second sheet 200 and determine the position information of the second target feature in the second image based on image recognition. Among them, the first target feature and the second target feature are respectively features located on the first sheet 100 and the second sheet 200 that need to be aligned when the first sheet 100 and the second sheet 200 are spliced. Specifically, the first target feature and the second target feature can be features such as the edge of the sheet, the printing on the sheet, and the pattern on the sheet that need to be aligned when the two sheets are spliced.

[0055] The control module 1 is communicatively connected to the driving unit 22. The control module 1 is used to calculate the moving direction and moving distance of the moving platform 21 according to the position information of the first target feature and the position information of the second target feature, and generate a driving control signal according to the calculated moving direction and moving distance of the moving platform 21. Among them, the driving control signal is used to control the driving unit 22 to drive the moving platform 21 to move to the target position so that the first target feature and the second target feature are aligned.

[0056] In use, first place the first sheet 100 at a preset position on the moving platform 21 (specifically, the first sheet 100 can be conveyed to the preset position on the moving platform 21 through a conveying mechanism such as conveying rollers that can convey sheets. Sheet conveyance is prior art and will not be elaborated here). At this time, the line array CCD sensor module 3 above the first sheet 100 scans and takes a photo of the first target area of the first sheet 100 to obtain a first image. At the same time, based on image recognition technology, the first target feature is recognized in the first image, and the position information of the first target feature is calculated and sent to the control module 1. Then, another conveying mechanism (not shown in the figure) conveys the second sheet 200 in a direction close to the first sheet 100 (as shown by the arrow on the first sheet 100 in Figure 1, that is, the positive direction of X). When the second sheet 200 is conveyed to a predetermined position, another line array CCD sensor module 3 scans and takes a photo of the second target area of the second sheet 200 to obtain a second image. At the same time, based on image recognition technology, the second target feature is recognized in the second image, and the position information of the second target feature is calculated and sent to the control module 1. Then, the control module 1 calculates the moving direction and moving distance of the moving platform 21 according to the position information of the first target feature and the position information of the second target feature detected by the two line array CCD sensor modules 3, and generates a drive control signal according to the calculated moving direction and moving distance of the moving platform 21 and sends it to the drive unit 22. The drive unit 22 drives the moving platform 21 to move to a target position in a certain direction (that is, the positive direction or negative direction of Y) along the direction indicated by the double-headed arrow on the moving platform 21 in Figure 1 the figure, so that the first target feature and the second target feature are aligned. After the first sheet 100 and the first sheet 100 are aligned, subsequent sheet splicing operations can be performed through the sheet splicing device.

[0057] The sheet splicing alignment system of this embodiment identifies the target features and determines the position information on the first sheet 100 and the second sheet 200 to be spliced through two linear array CCD sensor modules 3. It can effectively identify other target features such as printed lines and patterns in addition to the edge line features of the sheet, and can be applied to the alignment and splicing of two sheets with more types of target features and two sheets with larger position deviations, with a wider scope of application. Moreover, the detection range of the CCD sensor is wider than that of photoelectric sensors such as laser sensors. The detection range of the linear array CCD sensor can be adjusted to 50 mm. Generally, the deviation of the second sheet 200 during transmission is not so large. Therefore, compared with the sheet alignment system that uses a photoelectric sensor to detect the target features of the sheet, this system can better meet the alignment usage scenarios of materials with larger deviations, effectively reducing manual intervention. In addition, since the number of single-row pixels of the linear array CCD is much higher than that of the area array CCD and other photoelectric sensors, the resolution of the image of the target area obtained is also higher. Furthermore, the specific position information of the target features in the image obtained through image recognition technology is more accurate. Therefore, the drive control signal generated by the control module 1 according to the position information of the target features can more accurately control the drive unit 22 to make the mobile platform 21 move more precisely to the target position, thus effectively reducing the splicing error when splicing two sheets.

[0058] Specifically, in this embodiment, the photosensitive elements of the two linear array CCD sensor modules 3 are arranged along the Y direction, and the connection line between the photosensitive elements at the central positions of the two linear array CCD sensor modules 3 is parallel to the X direction. This enables the coordinate positions of each pixel of the two linear array CCD sensor modules 3 in the X direction to be aligned with each other, effectively avoiding the error between the detected position signal and the actual position information of the target features of the sheet, and better ensuring the detection accuracy to reduce the splicing alignment error.

[0059] Based on the previous embodiment, in one embodiment, the linear array CCD sensor module 3 includes an LCD touch screen, which is used to display the collected image and receive user interaction operations to mark the target features on the collected image. Through the LCD touch screen of the linear array CCD sensor module 3, the target features of the sheet can be intuitively and clearly displayed, and on-site operators can perform interactive operations such as zooming on the picture taken by the linear array CCD sensor through the LCD touch screen of the linear array CCD sensor module 3 to mark the target features of the sheet.

[0060] Based on the above embodiments, further, in one embodiment, the determining the position information of the first target feature in the first image based on image recognition includes:

[0061] Based on the differential algorithm and the fast Fourier transform, each first preselected feature in the first image with a chromaticity value jump greater than a preset chromaticity threshold is calculated to obtain a first preselected feature set, that is, each feature with a relatively large chromaticity value jump in the first image is selected; specifically, the first preselected features can be features such as edge lines, printing lines, and patterns in the first image.

[0062] The chromaticity values of the preselected features in the first preselected feature set are compared with the chromaticity values of the pre-marked target features, and the first target feature is determined according to the comparison result; since there may be multiple first preselected features with relatively large chromaticity value jumps in the first image, and when splicing the sheets, only the target features need to be aligned, therefore, it is also necessary to screen out the corresponding target features (i.e., the first target feature) in the first image from each first preselected feature by comparing with the chromaticity values of the pre-marked target features.

[0063] Based on the specific position of the pixel points corresponding to the first target feature in the first image, and the mapping relationship between the specific positions of the pixel points in the first image and the position coordinates of the pixel points in the imaging area of the linear array CCD sensor module 3, the position information of the first target feature is obtained; this position information is specifically the position coordinates of the first target feature.

[0064] Based on image recognition, the position information of the second target feature in the second image includes:

[0065] Based on the differential algorithm and the fast Fourier transform, each second preselected feature in the second image with a chromaticity value jump greater than a preset chromaticity threshold is calculated to obtain a second preselected feature set, that is, each feature with a relatively large chromaticity value jump in the second image is selected; specifically, the second preselected features can be features such as edge lines, printing lines, and patterns in the second image.

[0066] The chromaticity values of the preselected features in the second preselected feature set are compared with the chromaticity values of the pre-marked target features, and the second target feature is determined according to the comparison result; since there may be multiple second preselected features with relatively large chromaticity value jumps in the second image, and when splicing the sheets, only the target features need to be aligned, therefore, it is also necessary to screen out the corresponding target features (i.e., the second target feature) in the second image from each second preselected feature by comparing with the chromaticity values of the pre-marked target features.

[0067] Based on the specific position of the pixel points corresponding to the second target feature in the second image, and the mapping relationship between the specific positions of the pixel points in the second image and the position coordinates of the pixel points in the imaging area of the linear array CCD sensor module 3, the position information of the second target feature is obtained. This position information is specifically the position coordinates of the second target feature.

[0068] Specifically, the above preset chromaticity threshold can be specifically set according to the chromaticity values of different target features on different sheets.

[0069] Based on the previous embodiment, further, in one embodiment, the driving unit 22 specifically includes a driving motor, a driving gear, a driven gear, and a lead screw pair. The signal input end of the driving motor is connected to the control module 1. The output shaft of the driving motor is fixedly connected to the driving gear. The driving gear meshes with the driven gear. The driven gear is fixedly connected to the driving end of the lead screw of the lead screw pair. The nut of the lead screw pair is fixedly connected to the moving platform 21. By driving the driving gear with the driving motor, the driving gear drives the driven gear to rotate, and the rotation of the driven gear drives the lead screw of the lead screw pair to rotate, so that the moving platform 21 fixedly connected to the nut of the lead screw pair moves linearly along the Y direction, and the moving platform 21 drives the first sheet 100 to move along the Y direction, so that the first target feature on the first sheet 100 is aligned with the second target feature on the second sheet 200, ensuring the splicing accuracy.

[0070] Based on the previous embodiment, further, in one embodiment, calculating the moving direction and moving distance of the moving platform 21 according to the position information of the first target feature and the position information of the second target feature includes:

[0071] Obtaining the pixel point position corresponding to the first target feature according to the position information of the first target feature, the detection range of the line array CCD sensor module 3, and the resolution of the line array CCD sensor module 3;

[0072] Obtaining the pixel point position corresponding to the second target feature according to the position information of the second target feature, the detection range of the line array CCD sensor module 3, and the resolution of the line array CCD sensor module 3;

[0073] Obtaining the moving direction and moving distance of the moving platform 21 according to the pixel point position corresponding to the first target feature and the pixel point position corresponding to the second target feature.

[0074] Based on the previous embodiment, further, in one embodiment, generating a drive control signal according to the calculated moving direction and moving distance of the moving platform 21 includes:

[0075] Calculating the rotation direction and the number of turns required to rotate of the driving motor according to the calculated moving direction, moving distance of the moving platform 21, and the transmission ratio between the driving gear and the transmission gear;

[0076] Calculating the number of Hall pulses required to drive the driving motor based on the calculated number of turns required to rotate of the driving motor and the number of Hall pulses required for the driving motor to rotate one circle;

[0077] Generate a drive control signal based on the calculated number of Hall pulses required to drive the drive motor and the rotation direction of the drive motor.

[0078] To more intuitively understand the functions of this system, the alignment principle of two sheets of this system will be described in detail with a specific example below:

[0079] In this example, the detection range of the two linear CCD sensor modules 3 is ±20 mm. The output signal of the sensor is an analog quantity of 0 - 5 V, and the resolution is 1000, which is equivalent to dividing 40 mm into 1000 parts, and each part represents 0.04 mm. Suppose the linear CCD sensor module 3 on the second sheet 200 detects that the target feature (the edge line of the material in this embodiment) on the second sheet 200 is at the 400th pixel point, and the linear CCD sensor module 3 on the first sheet 100 detects that the target feature (the edge line) on the first sheet 100 is at the 550th pixel point. The difference is (550 - 400) * 0.04 mm;

[0080] The control module 1 calculates according to the above formula that this difference is +6 mm. Therefore, the drive motor needs to rotate forward to drive the moving platform 21 to run 6 mm along the positive Y-axis direction. The actuator 2 uses the drive motor as the power source, drives the screw of the screw pair to rotate through the driving gear and the driven gear, and the nut of the screw pair makes a reciprocating motion on the screw to drive the moving platform 21 to achieve the effect of moving forward and backward along the Y direction. In this example, the transmission ratio between the driving gear and the driven gear is 19:58, and the screw pitch is 4 mm. The control module 1 can thus calculate that the number of turns of the drive motor = (distance 6 mm / screw pitch 4 mm) / transmission ratio (19:58) ≈ 4.58 turns, that is, the drive motor needs to rotate 4.58 turns; since the number of Hall pulses per turn of the drive motor is 30, a total of 4.58 * 30 ≈ 137 pulses are required. The control module 1 precisely controls the drive motor to run 137 pulses, and then the moving platform 21 can drive the first sheet 100 to reach the target position to achieve the alignment of the target features between the first sheet 100 and the second sheet 200.

[0081] Error analysis: When the drive motor rotates 137 pulses, it rotates 4.567 turns. The screw rotates 4.567 / transmission ratio (19:58) ≈ 1.495 turns. The distance that the nut on the screw drives the moving platform 21 to run is 1.495 * screw pitch 4 = 5.98 mm, with an error of only 0.02 mm compared with the actual difference of 6 mm. It can be seen from this that in this system, the error during the alignment of the target features is very small.

[0082] In one embodiment, the linear array CCD sensor module 3 further includes a monochrome CCD chip, a main control MCU, and an RGB backlight module. The monochrome CCD chip and the RGB backlight module are respectively connected to the main control MCU. When the linear array CCD sensor module 3 collects an image of the corresponding sheet material, the RGB backlight module is started to irradiate the sheet material, and the main control MCU controls the monochrome CCD chip to scan the target area of the sheet material to achieve image acquisition of the target area. At the same time, the main control MCU realizes color restoration of the color sheet material on the image collected by the three-color CCD chip through backlight conversion of different colors.

[0083] Specifically, in one example, the circuit schematic diagram of the linear array CCD sensor module 3 is as Figure 2 shown. It can be seen from the figure that the linear array CCD sensor module 3 further includes a power supply part, a CCD chip driving circuit, and a communication part. The power supply part is used to supply power to the CCD sensor module, the CCD chip driving circuit is used to drive the monochrome CCD chip to work, and the communication part is used to interact and communicate with the control module 1.

[0084] Specifically, in one example, the circuit schematic diagram of the control module 1 is as Figure 3 shown. It can be seen from the figure that the control module 1 mainly includes a power supply part, a main control MCU, a communication part, a storage unit, a motor driving circuit, an interface circuit, and an external control circuit. Among them, the power supply part is used to provide working power for each unit circuit of the main control module, the main control MCU is used to generate a drive control signal according to the received position information of the target feature, the communication part is used for communication between the control module 1 and the linear array CCD sensor module 3, the storage unit is used to store preset parameters, data received by the control module 1, and data generated after calculation by the control module 1, the motor driving circuit is used to control the working state of the drive motor under the control of the main control MCU of the control module 1, the interface circuit is used to realize the connection between the control module 1 and other modules or devices, and the external control circuit is used to connect to an external monitoring terminal to realize mutual communication between the system and the external monitoring terminal.

[0085] As Figure 4 shown, the present invention also provides a method for splicing and aligning sheet materials based on a dual CCD sensor, which is applied to the sheet material splicing and aligning system based on a dual CCD sensor in any of the above embodiments. The method includes the following steps:

[0086] S1. Adjust the installation positions of the two linear array CCD sensor modules so that the photosensitive elements of the two linear array CCD sensor modules are arranged along the Y direction, and the connection line between the photosensitive elements at the central positions of the two linear array CCD sensor modules is parallel to the X direction;

[0087] S2. Initialize the sheet material splicing and aligning system;

[0088] S3. Place the first sheet and the second sheet at the position to be spliced, so that the corresponding target features of the first sheet and the second sheet are aligned, and the target features on the first sheet and the second sheet are respectively facing the center points of the two linear CCD sensor modules;

[0089] S4. Collect images of the first sheet and the second sheet through the two linear CCD sensor modules respectively, and mark the target features on the images collected by the two linear CCD sensor modules respectively;

[0090] S5. Start the sheet splicing and alignment system to align the first sheet and the second sheet to be spliced through the sheet splicing and alignment system.

[0091] In one embodiment, aligning the first sheet and the second sheet to be spliced through the sheet splicing and alignment system includes:

[0092] Collect a first image of a first target area corresponding to the first sheet through one of the linear CCD sensor modules, determine the position information of the first target feature in the first image based on image recognition, and collect a second image of a second target area corresponding to the second sheet through the other linear CCD sensor module, and determine the position information of the second target feature in the second image based on image recognition;

[0093] The control module calculates the moving direction and moving distance of the moving platform according to the position information of the first target feature and the position information of the second target feature, and generates a drive control signal according to the calculated moving direction and moving distance of the moving platform;

[0094] The drive unit drives the moving platform to move to the target position based on the drive control signal, so that the first target feature and the second target feature are aligned.

[0095] In this embodiment, if the modules / units integrated in the sheet splicing and alignment system based on dual CCD sensors are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on such an understanding, to implement all or part of the processes in the above-described embodiment methods of the present invention, it can also be completed by a computer program instructing relevant hardware. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by a processor, the steps of the above various method embodiments can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, executable file, or some intermediate form, etc. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disc, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the content included in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0096] Those skilled in the art can understand that although some embodiments herein include certain features included in other embodiments but not other features, the combination of features of different embodiments means that it is within the scope of the present invention and forms different embodiments. For example, in the following claims, any one of the claimed embodiments can be used in any combination.

[0097] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A sheet splicing and alignment system based on dual CCD sensors, which is used to align corresponding target features of a first sheet and a second sheet to be spliced that are placed side by side in the X direction. It is characterized in that, The sheet splicing and alignment system includes a control module, an actuator, and two linear array CCD sensor modules. Among them, The actuator includes a moving platform for placing the first sheet and a driving unit for driving the moving platform to move in the Y direction perpendicular to the X direction; The two linear array CCD sensor modules are respectively communicatively connected to the control module and are arranged side by side in the X direction. One linear array CCD sensor module is used to collect a first image of a first target area corresponding to the first sheet and determine the position information of the first target feature in the first image based on image recognition. The other linear array CCD sensor module is used to collect a second image of a second target area corresponding to the second sheet and determine the position information of the second target feature in the second image based on image recognition. Among them, the first target feature and the second target feature are respectively features located on the first sheet and the second sheet that need to be aligned when the first sheet and the second sheet are spliced; The control module is communicatively connected to the driving unit. The control module is used to calculate the moving direction and moving distance of the moving platform according to the position information of the first target feature and the position information of the second target feature, and generate a driving control signal according to the calculated moving direction and moving distance of the moving platform. Among them, the driving control signal is used to control the driving unit to drive the moving platform to move to a target position so that the first target feature and the second target feature are aligned.

2. The sheet splicing and alignment system based on a dual CCD sensor according to claim 1, wherein The photosensitive elements of the two linear array CCD sensor modules are all arranged in the Y direction, and the connection line between the photosensitive elements at the central positions of the two linear array CCD sensor modules is parallel to the X direction.

3. The sheet splicing and alignment system based on a dual CCD sensor according to claim 2, characterized in that, The linear array CCD sensor module includes an LCD touch screen, which is used to display the collected image and receive user interaction operations to mark the target feature on the collected image.

4. The sheet splicing and alignment system based on dual CCD sensors according to claim 3, characterized in that, Determining the position information of the first target feature in the first image based on image recognition includes: Calculating each first preselected feature in the first image whose chromaticity value jump is greater than a preset chromaticity threshold based on the difference algorithm and the fast Fourier transform to obtain a first preselected feature set; Comparing the chromaticity values of each preselected feature in the first preselected feature set with the chromaticity value of the pre-marked target feature, and determining the first target feature according to the comparison result; Obtaining the position information of the first target feature based on the specific position of the pixel points corresponding to the first target feature in the first image and the mapping relationship between the specific positions of each pixel point in the first image and the position coordinates of each pixel point in the imaging area of the linear array CCD sensor module; Determining the position information of the second target feature in the second image based on image recognition includes: Calculating each second preselected feature in the second image with a chromaticity value jump greater than a preset chromaticity threshold based on the difference algorithm and the fast Fourier transform to obtain a second preselected feature set; Comparing the chromaticity values of the preselected features in the second preselected feature set with the chromaticity values of the pre-marked target features, and determining the second target feature according to the comparison result; Based on the specific position of the pixel points corresponding to the second target feature in the second image, and the mapping relationship between the specific positions of the pixel points in the second image and the position coordinates of the pixel points in the imaging area of the linear array CCD sensor module, obtaining the position information of the second target feature.

5. The sheet splicing and alignment system based on a dual CCD sensor according to claim 4, characterized in that, The driving unit includes a driving motor, a driving gear, a driven gear and a lead screw pair. The signal input end of the driving motor is connected to the control module. The output shaft of the driving motor is fixedly connected to the driving gear. The driving gear meshes with the driven gear. The driven gear is fixedly connected to the driving end of the lead screw of the lead screw pair. The nut of the lead screw pair is connected to the moving platform.

6. The sheet splicing and alignment system based on a dual CCD sensor according to claim 5, wherein Calculating the moving direction and moving distance of the moving platform according to the position information of the first target feature and the position information of the second target feature includes: Obtaining the position of the pixel points corresponding to the first target feature according to the position information of the first target feature, the detection range of the linear array CCD sensor module, and the resolution of the linear array CCD sensor module; Obtaining the position of the pixel points corresponding to the second target feature according to the position information of the second target feature, the detection range of the linear array CCD sensor module, and the resolution of the linear array CCD sensor module; Obtaining the moving direction and moving distance of the moving platform according to the position of the pixel points corresponding to the first target feature and the position of the pixel points corresponding to the second target feature.

7. The sheet splicing and alignment system based on a dual CCD sensor according to claim 5, wherein Generating a drive control signal according to the calculated moving direction and moving distance of the moving platform includes: Calculating the rotation direction and the number of turns required to rotate of the driving motor according to the calculated moving direction and moving distance of the moving platform and the transmission ratio between the driving gear and the transmission gear; Calculating the number of Hall pulses required to drive the driving motor based on the calculated number of turns required to rotate the driving motor and the number of Hall pulses required for the driving motor to rotate one circle; Generating the drive control signal based on the calculated number of Hall pulses required to drive the driving motor and the rotation direction of the driving motor.

8. The sheet splicing and alignment system based on a dual CCD sensor according to any one of claims 3-7, characterized in that The linear array CCD sensor module further includes a monochrome CCD chip, a main control MCU and an RGB backlight module. The monochrome CCD chip and the RGB backlight module are respectively connected to the main control MCU.

9. A method for splicing and aligning sheets based on a dual CCD sensor, characterized in that, Applied to the sheet splicing and alignment system based on a dual CCD sensor according to any one of claims 1-8, the method includes the following steps: S1, Adjust the installation positions of the two linear CCD sensor modules so that the photosensitive elements of the two linear CCD sensor modules are arranged along the Y direction, and the connection line between the photosensitive elements at the central positions of the two linear CCD sensor modules is parallel to the X direction; S2, Initialize the sheet splicing and alignment system; S3, Place the first sheet and the second sheet at the position to be spliced, so that the corresponding target features of the first sheet and the second sheet are aligned, and the target features on the first sheet and the second sheet are respectively facing the center points of the two linear CCD sensor modules; S4, Collect the images of the first sheet and the second sheet through the two linear CCD sensor modules respectively, and mark the target features on the images collected by the two linear CCD sensor modules respectively; S5, Start the sheet splicing and alignment system to align the first sheet and the second sheet to be spliced through the sheet splicing and alignment system.

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