Machine vision-based inner card paper positioning compensation method and system

Abstract

The application discloses a kind of inner card paper positioning compensation method and system based on machine vision.The method comprises the following steps: after position calibration of conveying equipment and inner card paper, vision mechanism is carried out to inner card paper, and calibration coordinate is obtained;Encoder triggers vision mechanism, and vision mechanism obtains the image of inner card paper, and obtains the phase coordinate of inner card paper at corresponding phase;Vision mechanism compares phase coordinate with calibration coordinate, and obtains the offset error of inner card paper at corresponding phase;Processing unit analyzes offset error, if offset error is within offset range, then carry out rectification processing, and output speed compensation to conveying equipment;Conveying equipment adjusts the conveying speed of conveying equipment according to speed compensation, and compensates the conveying position of inner card paper.The present application introduces machine vision technology, improves the accuracy and efficiency of inner card paper positioning compensation, improves the accuracy of positioning and the accuracy of subsequent process.

Description

Technical Field

[0001] This invention relates to the field of machine vision technology, and in particular to a machine vision-based method and system for compensating for internal paper jam positioning. Background Technology

[0002] With the deepening of tobacco industry reforms, cigarette manufacturers are increasingly demanding higher standards for inner cardboard development. Inner cardboard has evolved from single-color to multi-color designs, especially in high-end cigarettes, where colored patterned inner cardboard is becoming widely used and is one of the important directions in Chinese cigarette research.

[0003] Existing cutting equipment for inner cardboard uses mechanical phase positioning. In actual production, the tension force on the inner cardboard is not absolutely balanced. In addition, due to factors such as machine vibration, the conveying speed of the inner cardboard often changes, resulting in the color mark on the inner cardboard lagging or leading, which causes errors in the cutting position.

[0004] Currently, inner cardboard cutting equipment is equipped with corresponding correction devices to adjust the conveying speed of the inner cardboard, thereby ensuring precise cutting. The correction devices mainly employ two schemes: a traditional mechanical differential speed compensation scheme or a servo-controlled electronic clutch scheme. The traditional mechanical differential speed compensation scheme uses the speed differences of different components in the mechanical mechanism design to compensate for deviations in the inner cardboard during conveying. However, this method has limitations and cannot completely guarantee the conveying accuracy of the inner cardboard. The servo-controlled electronic clutch scheme uses a servo-controlled electronic clutch to adjust the conveying speed and tension of the inner cardboard. This method also cannot completely guarantee the conveying accuracy of the inner cardboard.

[0005] In the process of realizing this invention, the inventors discovered at least the following problems in the prior art.

[0006] The correction devices and methods used in the inner cardboard cutting equipment cannot guarantee the conveying accuracy of the inner cardboard, which will affect the subsequent processing of the inner cardboard. Summary of the Invention

[0007] The purpose of this invention is to provide a machine vision-based method and system for inner cardboard positioning compensation, in order to solve the technical problem that the correction devices and methods used in the existing inner cardboard cutting equipment cannot guarantee the conveying accuracy of the inner cardboard, which will affect the subsequent processing steps of the inner cardboard.

[0008] The preferred technical solutions among the many technical solutions provided by this invention can produce a variety of technical effects, which are described in detail below.

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] In a first aspect, the present invention provides a machine vision-based method for compensating for the positioning of internal paper jams conveyed on a conveying device, the method comprising:

[0011] After the conveying equipment and the inner card are calibrated, the vision mechanism performs calibration processing on the inner card to obtain calibration coordinates;

[0012] The encoder calculates the working position and conveying speed of the conveying device. When the inner card moves to the corresponding phase, the encoder triggers the vision mechanism to acquire an image of the inner card and obtain the phase coordinates of the inner card at the corresponding phase.

[0013] The vision mechanism compares the phase coordinates with the calibration coordinates to obtain the offset error of the inner card at the corresponding phase, and sends the offset error to the processing unit.

[0014] The processing unit analyzes the offset error. If the offset error is within the offset range, it performs correction processing and outputs the speed compensation amount to the conveying device.

[0015] The conveying equipment adjusts its conveying speed according to the speed compensation amount to compensate for the conveying position of the inner cardboard.

[0016] Optionally, if the offset error is within the offset range, a correction process is performed, and a speed compensation amount is output to the conveying device, including:

[0017] If the offset error is within a first offset range, a first speed compensation amount is output to the conveying device, wherein the first offset range is...

[0018] If the offset error is within the second offset range, a second speed compensation amount is output to the conveying device, wherein the second offset range is...

[0019] If the offset error is within the third offset range, a third speed compensation amount is output to the conveying device, wherein the third offset range is...

[0020] If the offset error is within the fourth offset range, a fourth speed compensation amount is output to the conveying device, wherein the fourth offset range is...

[0021] Where 'a' is the bag making length; the speed compensation amount is calculated based on the bag making length, the offset error, and the offset range.

[0022] Optionally, the formula for the speed compensation amount is:

[0023] Speed ​​compensation amount = (offset error / bag length) * actual speed;

[0024] The actual speed is the conveying speed of the conveying device at the corresponding phase, calculated by the encoder.

[0025] Optionally, the bag length is the actual length of a single inner cardboard sheet conveyed along the conveying direction of the conveying equipment.

[0026] Optionally, the conveying device adjusts its conveying speed according to the speed compensation amount, including:

[0027] When the conveying equipment receives the first speed compensation amount or the second speed compensation amount, the conveying equipment performs acceleration compensation; the formula for the conveying speed of the conveying equipment performing acceleration compensation is:

[0028] Conveying speed = actual speed + first speed compensation amount or second speed compensation amount.

[0029] Optionally, the conveying device adjusts its conveying speed according to the speed compensation amount, further comprising:

[0030] When the conveying equipment receives the third speed compensation amount or the fourth speed compensation amount, the conveying equipment performs deceleration compensation; the formula for the conveying speed of the conveying equipment performing deceleration compensation is:

[0031] Conveying speed = Actual speed - Third speed compensation amount or fourth speed compensation amount.

[0032] Optionally, the vision mechanism calibrates the inner card using a quadrilateral search method.

[0033] Optionally, after the vision mechanism compares the phase coordinates with the calibration coordinates to obtain the offset error of the inner card at the corresponding phase, and sends the offset error to the processing unit, the method further includes:

[0034] If the offset error is not within the offset range, the processing unit outputs a rejection compensation amount and sends the rejection compensation amount to the conveying device. The conveying device adjusts its conveying speed according to the rejection compensation amount to reject the inner jammed paper.

[0035] Secondly, the present invention also provides an internal paper jam positioning compensation system based on machine vision, characterized in that it is used to perform the above-described internal paper jam positioning compensation method based on machine vision, the system including a conveying device, a vision mechanism, an encoder and a processing unit, wherein the conveying device and the vision mechanism are both connected to the encoder and the processing unit.

[0036] The conveying equipment is used to convey inner cardboard.

[0037] The vision mechanism is located above the conveying device and is used to acquire the calibration coordinates of the inner card after position calibration and the phase coordinates of the inner card when it is conveyed to the corresponding phase on the conveying device. The phase coordinates are compared with the calibration coordinates to calculate the offset error of the inner card at the corresponding phase.

[0038] The encoder is used to collect the conveying speed of the conveying equipment and trigger the vision mechanism to acquire images under the original synchronous phase.

[0039] The processing unit is used to analyze the offset error and output a speed compensation amount to the conveying device, so that the conveying device can compensate for the conveying position of the inner card.

[0040] Optionally, the conveying device includes a paper feeding mechanism, a servo drive mechanism, and a conveying guide rail. The paper feeding mechanism is connected to the servo drive mechanism, and the conveying guide rail is used to cooperate with the paper feeding mechanism to convey the inner jammed paper. The servo drive mechanism is used to correct the conveying speed of the paper feeding mechanism according to the speed compensation amount output by the processing unit.

[0041] Implementing one of the above-described technical solutions of the present invention has the following advantages or beneficial effects:

[0042] This invention describes a machine vision-based method for inner paper jam positioning compensation. By acquiring calibration coordinates, an encoder collects speed signals and controls a vision mechanism to obtain phase coordinates. The phase coordinates are compared with the calibration coordinates, and the offset error is analyzed. The speed compensation amount is calculated, and finally, the conveying speed of the conveying equipment is corrected, achieving accurate positioning of the inner paper jam in subsequent processes. This invention introduces machine vision technology, realizing an automated and intelligent positioning compensation process, improving the accuracy and efficiency of inner paper jam positioning compensation, and enhancing the accuracy of positioning and the precision of subsequent processes. Attached Figure Description

[0043] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In the drawings:

[0044] Figure 1 This is a flowchart illustrating the internal paper jam positioning compensation method based on machine vision, according to Embodiment 1 of the present invention.

[0045] Figure 2 This is a schematic diagram of the overall structure of the machine vision-based internal paper jam positioning compensation system according to Embodiment 2 of the present invention;

[0046] Figure 3 This is a schematic diagram of the connection between the paper feeding device and the vision device in the machine vision-based internal paper jam positioning compensation system according to Embodiment 2 of the present invention.

[0047] In the diagram: 1. Conveying equipment; 11. Paper feeding mechanism; 12. Servo drive mechanism; 13. Conveying guide rail; 2. Vision mechanism; 3. Encoder; 4. Processing unit; 5. Internal paper jam. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of the present invention clearer, various exemplary embodiments described below will be referenced to the accompanying drawings, which form part of the exemplary embodiments, illustrating various exemplary embodiments that may be used to implement the present invention. Unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. It should be understood that they are merely examples of processes, methods, and apparatuses consistent with some aspects of the present invention disclosed as detailed in the appended claims, and other embodiments may be used, or structural and functional modifications may be made to the embodiments listed herein without departing from the scope and spirit of the present invention.

[0049] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," etc., indicate the orientation or positional relationship based on the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the referred element must have a specific orientation, or be constructed and operated in a specific orientation. The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. The term "a plurality" means two or more. The terms "connected" and "linked" should be interpreted broadly, for example, they can refer to fixed connections, detachable connections, integral connections, mechanical connections, electrical connections, communication connections, direct connections, indirect connections through an intermediate medium, and can refer to the internal communication of two elements or the interaction relationship between two elements. The term "and / or" includes any and all combinations of one or more of the related listed items. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0050] To illustrate the technical solution described in this invention, specific embodiments are described below, showing only the parts related to the embodiments of this invention.

[0051] Example 1:

[0052] like Figure 1 As shown, this invention provides a machine vision-based method for compensating for internal paper jams, used to compensate for the positioning of internal paper jams conveyed on a conveying device. The method includes:

[0053] S10. After the position of the conveying equipment and the inner card is calibrated, the vision mechanism performs calibration processing on the inner card to obtain the calibration coordinates.

[0054] S20. The encoder calculates the working position and conveying speed of the conveying equipment. When the inner paper jam moves to the corresponding phase, the encoder triggers the vision mechanism to obtain the image of the inner paper jam and obtain the phase coordinates of the inner paper jam at the corresponding phase.

[0055] S30. The vision mechanism compares the phase coordinates with the calibration coordinates to obtain the offset error of the inner card at the corresponding phase, and sends the offset error to the processing unit.

[0056] S40. The processing unit analyzes the offset error. If the offset error is within the offset range, it performs correction processing and outputs the speed compensation amount to the conveying equipment.

[0057] S50. The conveying equipment adjusts its conveying speed according to the speed compensation amount to compensate for the conveying position of the inner paper jam.

[0058] Specifically, this embodiment can perform positioning compensation for inner cardboard conveyed on a conveying device. The specific method involves: after the conveying device and the inner cardboard are calibrated, the vision mechanism calibrates the inner cardboard to obtain calibration coordinates. This step allows the inner cardboard to obtain its calibration coordinates when it is in a standard position on the conveying device, and these coordinates are used as a reference for subsequent comparisons. Then, as the conveying device conveys the inner cardboard, the encoder calculates the working position and conveying speed of the conveying device. When the inner cardboard moves to the corresponding phase, the encoder triggers the vision mechanism, enabling it to acquire an image of the inner cardboard and obtain its phase coordinates at that phase. In this step, the vision mechanism uses the encoder to determine the phase coordinates of the inner cardboard when it moves to a specific phase.

[0059] Next, the vision mechanism compares the phase coordinates with the calibration coordinates to obtain the offset error of the inner cardboard at the corresponding phase, and sends this offset error to the processing unit. The vision mechanism compares the phase coordinates and calibration coordinates, calculating the difference between them. This difference is the offset error of the inner cardboard at the corresponding phase, reflecting the degree of deviation between the actual position and the standard position of the inner cardboard. Subsequently, the processing unit analyzes the offset error. If the offset error is within the offset range, it performs correction processing and outputs a speed compensation amount to the conveying equipment. After detecting that the offset error is within the offset range, it performs correction processing and outputs a speed compensation amount to adjust the speed of the conveying equipment. Finally, the conveying equipment adjusts its conveying speed according to the speed compensation amount to compensate for the conveying position of the inner cardboard. By changing the speed to compensate for the conveying position of the inner cardboard, the conveying equipment aims to bring the inner cardboard back to the standard conveying position as much as possible, ensuring conveying accuracy and guaranteeing the accuracy of subsequent operations on the inner cardboard.

[0060] This embodiment describes a machine vision-based internal paper jam positioning compensation method. By acquiring calibration coordinates, an encoder collects speed signals and controls a vision mechanism to obtain phase coordinates. The phase coordinates are compared with the calibration coordinates, and the offset error is analyzed. The speed compensation amount is calculated, and finally, the conveying speed of the conveying equipment is corrected, achieving accurate positioning of the internal paper jam in subsequent processes. This embodiment introduces machine vision technology, realizing an automated and intelligent positioning compensation process, improving the accuracy and efficiency of internal paper jam positioning compensation, and enhancing the accuracy of positioning and the precision of subsequent processes.

[0061] Below, we will combine Figure 1 The machine vision-based internal paper jam positioning compensation method described in this embodiment will be explained in detail:

[0062] First, in step S10, after the position calibration of the conveying equipment and the inner cardboard, the vision mechanism calibrates the inner cardboard to obtain calibration coordinates. Specifically, after powering on, the conveying equipment initializes and performs position calibration to ensure the inner cardboard is in the accurate position, providing a stable foundation for subsequent calibration. Then, the vision mechanism performs a quadrilateral search on the inner cardboard at the standard position for calibration. The specific calibration process involves using the vision camera in the vision mechanism to find the edge of the inner cardboard, then calibrating the coordinates of that edge, and finally calibrating the coordinates of the center point of the color mark to obtain the calibration coordinates.

[0063] Among these, color marks refer to the parts on the inner card that serve a specific identifying function. Marking the coordinates of their center points helps to more accurately identify and locate the inner card. The calibration coordinates of the inner card obtained through the above steps will serve as the basis for subsequent phase coordinate positioning.

[0064] Then, in step S20, the encoder calculates the working position and conveying speed of the conveying device. When the inner paper moves to the corresponding phase, the encoder triggers the vision mechanism to acquire an image of the inner paper and obtain the phase coordinates of the inner paper at the corresponding phase.

[0065] Specifically, an encoder is a device that measures mechanical motion parameters. After being installed on a conveyor, the encoder converts the mechanical motion of the equipment into electrical or digital signals through internal sensing and computing mechanisms. This allows for real-time acquisition of the conveyor's working position and speed, enabling precise monitoring of its operating status. Specifically, an encoder includes A-pulses and Z-pulses. The A-pulse is used to acquire the conveyor's operating speed, while the Z-pulse triggers the vision mechanism. By driving the vision mechanism with the Z-pulse, it ensures that the camera's image acquisition is synchronized with the machine's operation, achieving synchronized image acquisition and guaranteeing that the acquired image accurately reflects the current operating status of the conveyor.

[0066] Among them, working position refers to the current working position of the conveying equipment, that is, where the equipment is in the entire process; conveying speed is the speed at which the conveying equipment moves.

[0067] Then, when the encoder calculates that the inner paper has moved to a pre-set specific phase, the system triggers the vision mechanism, which uses its vision camera to acquire images of the inner paper for subsequent analysis. After acquiring the image of the inner paper, the vision mechanism uses image processing and analysis techniques to perform a quadrilateral search to confirm the specific coordinate position of the inner paper at the corresponding phase, obtaining the phase coordinates. More specifically, the phase coordinates can accurately represent the specific position of the inner paper in the conveying device at the current phase. Step S20 uses the encoder to monitor the movement of the conveying device and the inner paper, triggers the vision mechanism at a specific position to acquire an image of the inner paper, and obtains the precise position information of the inner paper through image processing, providing data support for subsequent operations.

[0068] Next, in step S30, the vision mechanism compares the phase coordinates with the calibration coordinates to obtain the offset error of the inner cardboard at the corresponding phase, and sends the offset error to the processing unit. Specifically, after obtaining the phase coordinates of the inner cardboard using the vision mechanism, it also compares the phase coordinates with the calibration coordinates and calculates the difference between the two. This gives the difference between the actual position and the theoretical position of the inner cardboard at the corresponding phase, reflecting the positional deviation of the inner cardboard during the conveying process and providing a basis for subsequent position compensation. The offset error obtained by the vision mechanism after comparison is sent to the processing unit for further processing.

[0069] Subsequently, step S40 is executed, where the processing unit analyzes the offset error. If the offset error is within the offset range, correction processing is performed, and a speed compensation amount is output to the conveying equipment. Specifically, for offset errors within the offset range, correction processing is performed, and corresponding corrective measures are taken to make the actual value as close as possible to the expected value. After completing the correction processing, to ensure the accurate conveying of the inner cardboard by the conveying equipment, a speed compensation amount is calculated and output. The speed compensation amount can be used to adjust the operating speed of the conveying equipment to compensate for the impact of the offset error.

[0070] In this embodiment, the offset error is analyzed. If the offset error is within the offset range, the offset correction process is performed, and the speed compensation amount is output, including the following cases.

[0071] If the offset error is within the first offset range, a first speed compensation amount is output to the conveying device, wherein the first offset range is: If the offset error is within the second offset range, a second speed compensation amount is output to the conveying device, wherein the second offset range is: If the offset error is within the third offset range, the third speed compensation amount is output to the conveying equipment, where the third offset range is... If the offset error is within the fourth offset range, a fourth speed compensation amount is output to the conveying equipment, where the fourth offset range is... Where 'a' represents the bag making length; the speed compensation amount is calculated based on the bag making length, offset error, and offset range.

[0072] Since the inner paper may be ahead or behind during actual conveying, the processing unit will analyze the offset error after receiving it. If the offset error is within the offset range, the corresponding speed compensation amount will be output according to the different ranges of the offset error.

[0073] For the first case, when the offset error is within... Within this range, the first speed compensation amount is output. The negative sign here indicates that the offset direction is opposite to a certain defined positive direction.

[0074] Regarding the second scenario, when the offset error is within... This range will output the second velocity compensation amount. This range indicates that the offset error is relatively small and biased towards the negative direction.

[0075] Regarding the third scenario, when the offset error is within... During this range, the third speed compensation amount is output. This range means that the offset error is in a positive direction and the value is relatively small.

[0076] Regarding the fourth scenario, when the offset error is within... Within this range, the fourth speed compensation amount is output. This range indicates that the offset error is in a positive direction and the value is relatively large.

[0077] In this embodiment, the processing unit outputs different speed compensation amounts for adjusting the conveying equipment according to the different ranges of the offset error. This can correct the impact of the offset error and achieve dynamic adjustment of the conveying speed of the conveying equipment to ensure the accuracy and stability of subsequent operations.

[0078] Furthermore, in this embodiment, 'a' refers to the bag-making length. The bag-making length is a pre-set fixed length value and serves as an important reference standard in this embodiment. Specifically, in this embodiment, the bag-making length refers to the actual length of a single inner cardboard sheet conveyed along the conveying direction of the conveying equipment.

[0079] In this embodiment, the formula for speed compensation is: Speed ​​compensation = (Offset error / Bag length) * Actual speed; where the actual speed is the conveying speed of the conveyor equipment at the corresponding phase, calculated by the encoder. Specifically, the speed compensation is calculated based on the ratio between the offset error and the bag length, combined with the actual speed of the conveyor equipment, to determine the amount of speed compensation required. This allows for adjustment of the conveyor equipment speed, ensuring production accuracy and stability. For example, when the offset error is large, the calculated speed compensation will also be larger, and the offset error can be reduced by adjusting the conveyor speed.

[0080] Finally, step S50 is executed, in which the conveying equipment adjusts its conveying speed according to the speed compensation amount to compensate for the conveying position of the inner paper jam.

[0081] It should be noted that after the processing unit outputs the speed compensation amount to the conveying equipment, the conveying equipment adjusts its conveying speed according to the speed compensation amount to compensate for the conveying position of the inner paper jam. Since the conveying equipment compensates for the conveying position of the inner paper jam based on the speed compensation amount, two different compensation situations will occur.

[0082] The first type of compensation occurs when the conveying equipment receives either the first or second speed compensation amount, at which point the conveying equipment performs acceleration compensation.

[0083] At this point, because the phase coordinates of the first and second speed compensation values ​​lag behind the calibration coordinates, it is necessary to output both values ​​to increase the speed of the conveying equipment. This allows the inner card to move more quickly, thus shortening the deviation between the inner card and the preset position. This acceleration compensation typically occurs when the actual position of the inner card is significantly behind the preset position. By increasing the conveying speed, the position of the inner card can be quickly adjusted, ensuring it accurately reaches the designated position during subsequent processing or packaging.

[0084] At this time, the formula for the conveying speed of the conveying equipment that performs acceleration compensation is: Conveying speed = Actual speed + First speed compensation amount or Second speed compensation amount.

[0085] The second type of compensation occurs when the conveying equipment receives a third or fourth speed compensation amount, at which point the conveying equipment performs deceleration compensation.

[0086] At this point, because the phase coordinates of the output third and fourth speed compensation values ​​are ahead of the calibration coordinates, it is necessary to output the third and fourth speed compensation values ​​to reduce the speed of the conveying equipment, thereby slowing down the movement of the inner paper jam and extending the time it takes for the inner paper jam to reach the preset position. This deceleration compensation usually occurs when the actual position of the inner paper jam is significantly ahead of the preset position. By reducing the conveying speed, the inner paper jam can be prevented from arriving at or exceeding the preset position prematurely, thus ensuring its accurate positioning in subsequent processes.

[0087] At this time, the formula for the conveying speed of the conveying equipment that performs deceleration compensation is: Conveying speed = Actual speed - Third speed compensation amount or Fourth speed compensation amount.

[0088] After step S50 is completed, the compensation for the inner cardboard's feeding position and the correction for its feeding speed are finished, ensuring accurate positioning of the inner cardboard in subsequent processes and improving the accuracy and efficiency of positioning compensation. In this embodiment, the subsequent process can be the cutting process of the inner cardboard.

[0089] As some alternative implementations, after step S30, other steps may be performed based on the comparison between the phase coordinates and the calibration coordinates.

[0090] Specifically, after comparing the phase coordinates with the calibration coordinates to obtain the offset error of the inner paper jam at the corresponding phase, the process also includes: analyzing the offset error; if the offset error is not within the offset range, the processing unit outputs a rejection compensation amount and sends the rejection compensation amount to the conveying equipment; the conveying equipment adjusts its conveying speed according to the rejection compensation amount to reject the inner paper jam.

[0091] If, after analyzing the offset error, it is determined that the offset error is outside the acceptable range, it indicates that the offset of the inner cardboard has exceeded the acceptable range, which may affect product quality or the production process. In this case, the system will calculate a rejection compensation amount based on the magnitude of the offset error. This rejection compensation amount is a parameter used to adjust the operating status of the conveyor equipment, with the aim of rejecting non-compliant inner cardboard.

[0092] After receiving the rejection compensation amount, the conveying equipment adjusts its conveying speed accordingly. By changing the conveying speed, inner cardboard with excessive offset errors can be rejected from the conveying line, ensuring that the inner cardboard used in subsequent production processes is within the allowable offset range, thereby improving product quality and production efficiency.

[0093] The embodiment is merely a specific example and does not indicate that this is the only way to implement the present invention.

[0094] Example 2:

[0095] Based on the same inventive concept, the second embodiment of the present invention also provides a machine vision-based inner cardboard 5 positioning compensation system, used to execute the machine vision-based inner cardboard 5 positioning compensation method described in Embodiment 1. The system includes a conveying device 1, a vision mechanism 2, an encoder 3, and a processing unit 4. The conveying device 1 and the vision mechanism 2 are both connected to the encoder 3 and the processing unit 4. The conveying device 1 is used to convey the inner cardboard 5. The vision mechanism 2 is located above the conveying device 1 and is used to acquire the calibration coordinates of the inner cardboard 5 after position calibration and the phase coordinates of the inner cardboard 5 when it is conveyed to the corresponding phase on the conveying device 1. The phase coordinates are compared with the calibration coordinates to calculate the offset error of the inner cardboard 5 at the corresponding phase. The encoder 3 is used to acquire the conveying speed of the conveying device 1 and trigger the vision mechanism 2 to acquire images under the original machine synchronous phase. The processing unit 4 is used to analyze the offset error and output the speed compensation amount to the conveying device 1 so that the conveying device 1 compensates for the conveying position of the inner cardboard 5.

[0096] Specifically, the positioning compensation system described in this embodiment consists of four parts: a conveying device 1, a vision mechanism 2, an encoder 3, and a processing unit 4. The conveying device 1 and the vision mechanism 2 are connected to the encoder 3 and the processing unit 4 to realize data interaction and collaborative work between the parts.

[0097] More specifically, the main function of the conveying device 1 is to convey the inner card 5, and it is the power source for the movement of the inner card 5 in the entire system.

[0098] The conveying device 1 includes a paper feeding mechanism 11, a servo drive mechanism 12, and a conveying guide rail 13. The paper feeding mechanism 11 is connected to the servo drive mechanism 12, and the conveying guide rail 13 works in conjunction with the paper feeding mechanism 11 to convey the inner cardboard 5. The servo drive mechanism 12 corrects the conveying speed of the paper feeding mechanism 11 based on the speed compensation amount output by the processing unit 4. Specifically, the paper feeding mechanism 11 is the basic component responsible for paper conveying and is the direct execution part for conveying the inner cardboard 5. The servo drive mechanism 12 is connected to the paper feeding mechanism 11 and can control and adjust the operation of the paper feeding mechanism 11. The conveying guide rail 13 works in conjunction with the paper feeding mechanism 11 to assist in conveying the inner cardboard 5 and provide guidance for paper conveying. It should be noted that the servo drive mechanism 12 receives the speed compensation amount output by the processing unit 4 and corrects the conveying speed of the paper feeding mechanism 11 based on this compensation amount to ensure the accuracy and stability of the conveying speed and avoid the conveying effect being affected by speed deviation.

[0099] The vision mechanism 2, located above the conveying device 1, acquires the calibration coordinates of the inner cardboard 5 at a standard position. These calibration coordinates can be understood as the ideal position information of the inner cardboard 5. Furthermore, the vision mechanism 2 works in conjunction with the encoder 3 to acquire the phase coordinates of the inner cardboard 5 as it is conveyed to the corresponding phase on the conveying device 1. It also compares the acquired phase coordinates with the previously obtained calibration coordinates, calculating the offset error of the inner cardboard 5 at the corresponding phase. This offset error represents the deviation between the actual position and the ideal position of the inner cardboard 5.

[0100] The opening and closing of encoder 3 is controlled by processing unit 4. Encoder 3 is used to collect the conveying speed of conveyor 1 and trigger vision mechanism 2 to collect images under the original synchronous phase, ensuring that the image information collected by vision mechanism 2 is synchronized with the operating status of conveyor 1, and ensuring the accuracy of data.

[0101] The processing unit 4 receives the offset error calculated by the vision mechanism 2, analyzes and processes it, and then outputs a speed compensation amount to the conveying device 1 based on the analysis results. The conveying device 1 adjusts the conveying position of the inner cardboard 5 according to this speed compensation amount, thereby reducing the offset error of the inner cardboard 5 and ensuring that the inner cardboard 5 is conveyed as close to the ideal position as possible, improving the positioning accuracy and the precision of subsequent processes.

[0102] The system described in this embodiment acquires the conveying speed through encoder 3 and triggers vision mechanism 2 to acquire images. Vision mechanism 2 obtains the coordinate information of inner cardboard 5 and calculates the offset error. Processing unit 4 analyzes the error and outputs compensation amount. Conveying device 1 adjusts the conveying position according to the compensation amount, forming a closed-loop control system to improve the system's motion accuracy and working quality, and improve the accuracy of inner cardboard 5 conveying.

[0103] In this embodiment, if an offset error of the inner cardboard 5 is detected during the conveying process, the processing unit 4 will quickly calculate the corresponding speed compensation amount and send the speed compensation amount to the servo drive mechanism 12. After receiving the speed compensation amount, the servo drive mechanism 12 will adjust the conveying speed of the paper feeding mechanism 11. This adjustment is dynamic and real-time, ensuring that the paper feeding mechanism 11 maintains an ideal conveying speed when conveying the inner cardboard 5. Furthermore, the conveying guide rail 13 has a guiding function, enabling the inner cardboard 5 to maintain a stable conveying path during the conveying process, further reducing the possibility of offset errors.

[0104] In summary, through the coordinated operation of the paper feeding mechanism 11, the servo drive mechanism 12, and the conveying guide rail 13 in the conveying device 1, and the precise calculation and output of the speed compensation amount by the processing unit 4, the system in this embodiment can achieve high precision and high stability in the conveying of the inner card 5, providing a reliable foundation for subsequent processing steps.

[0105] The above description is merely a preferred embodiment of the present invention. Those skilled in the art will understand that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the present invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. A machine vision-based method for compensating for internal paper jam positioning, characterized in that, The method for positioning compensation of inner cardboard being conveyed on a conveying device includes: After the conveying equipment and the inner card are calibrated, the vision mechanism performs calibration processing on the inner card to obtain calibration coordinates; The encoder calculates the working position and conveying speed of the conveying device. When the inner card moves to the corresponding phase, the encoder triggers the vision mechanism to acquire an image of the inner card and obtain the phase coordinates of the inner card at the corresponding phase. The vision mechanism compares the phase coordinates with the calibration coordinates to obtain the offset error of the inner card at the corresponding phase, and sends the offset error to the processing unit. The processing unit analyzes the offset error. If the offset error is within the offset range, it performs correction processing and outputs the speed compensation amount to the conveying device. The conveying equipment adjusts its conveying speed according to the speed compensation amount to compensate for the conveying position of the inner cardboard. If the offset error is within the offset range, then a correction process is performed, and a speed compensation amount is output to the conveying device, including: If the offset error is within a first offset range, a first speed compensation amount is output to the conveying device, wherein the first offset range is (-a, - a) If the offset error is within the second offset range, a second speed compensation amount is output to the conveying device, wherein the second offset range is (- a, 0a); If the offset error is within the third offset range, a third speed compensation amount is output to the conveying device, wherein the third offset range is (0a, ...). a) If the offset error is within the fourth offset range, a fourth speed compensation amount is output to the conveying device, wherein the fourth offset range is ( a, a); Where 'a' is the bag making length; the speed compensation amount is calculated based on the bag making length, the offset error, and the offset range; The vision mechanism calibrates the inner cardboard using a quadrilateral search method. The calibration process involves using the vision camera in the vision mechanism to find the edge of the inner cardboard, then calibrating the coordinates of the edge, and finally calibrating the coordinates of the center point of the color mark to obtain the calibration coordinates. The formula for the speed compensation amount is: Speed ​​compensation amount = (offset error / bag length) Actual speed; Wherein, the actual speed is the conveying speed of the conveying device at the corresponding phase, calculated by the encoder; The bag length is the actual length of a single sheet of inner cardboard conveyed along the conveying direction of the conveying equipment.

2. The machine vision-based internal paper jam positioning compensation method according to claim 1, characterized in that, The conveying equipment adjusts its conveying speed according to the speed compensation amount, including: When the conveying equipment receives the first speed compensation amount or the second speed compensation amount, the conveying equipment performs acceleration compensation; the formula for the conveying speed of the conveying equipment performing acceleration compensation is: Conveying speed = actual speed + first speed compensation amount or second speed compensation amount.

3. The machine vision-based internal paper jam positioning compensation method according to claim 1, characterized in that, The conveying equipment adjusts its conveying speed according to the speed compensation amount, and further includes: When the conveying equipment receives the third speed compensation amount or the fourth speed compensation amount, the conveying equipment performs deceleration compensation; the formula for the conveying speed of the conveying equipment performing deceleration compensation is: Conveying speed = actual speed - third speed compensation amount or fourth speed compensation amount.

4. The machine vision-based internal paper jam positioning compensation method according to claim 1, characterized in that, After the vision mechanism compares the phase coordinates with the calibration coordinates to obtain the offset error of the inner card at the corresponding phase, and sends the offset error to the processing unit, the method further includes: If the offset error is not within the offset range, the processing unit outputs a rejection compensation amount and sends the rejection compensation amount to the conveying device. The conveying device adjusts its conveying speed according to the rejection compensation amount to reject the inner jammed paper.

5. A machine vision-based internal paper jam positioning compensation system, characterized in that, The system is used to perform the machine vision-based internal paper jam positioning compensation method according to any one of claims 1-4, the system comprising a conveying device, a vision mechanism, an encoder and a processing unit, wherein the conveying device and the vision mechanism are both connected to the encoder and the processing unit; The conveying equipment is used to convey inner cardboard. The vision mechanism is located above the conveying device and is used to acquire the calibration coordinates of the inner card after position calibration and the phase coordinates of the inner card when it is conveyed to the corresponding phase on the conveying device. The phase coordinates are compared with the calibration coordinates to calculate the offset error of the inner card at the corresponding phase. The encoder is used to collect the conveying speed of the conveying equipment and trigger the vision mechanism to acquire images under the original synchronous phase. The processing unit is used to analyze the offset error and output a speed compensation amount to the conveying device, so that the conveying device can compensate for the conveying position of the inner card.

6. The machine vision-based internal paper jam positioning compensation system according to claim 5, characterized in that, The conveying device includes a paper feeding mechanism, a servo drive mechanism, and a conveying guide rail. The paper feeding mechanism is connected to the servo drive mechanism, and the conveying guide rail is used to cooperate with the paper feeding mechanism to convey the inner jammed paper. The servo drive mechanism is used to correct the conveying speed of the paper feeding mechanism according to the speed compensation amount output by the processing unit.

Images