A method, device and equipment for calculating the warping degree of corrugated board

Abstract

The present invention discloses a method, device and equipment for calculating the warping degree of corrugated cardboard. The method includes: receiving the first point cloud data of several corrugated cardboards collected by a 3D camera; extracting multiple groups of second point cloud data row by row from the first point cloud data; determining the cutting points of the corrugated cardboard according to the data distribution state of the second point cloud data, and determining the third point cloud data corresponding to each cut corrugated paper block according to the cutting points; performing curve fitting on the third point cloud data, and determining the warping degree of each corrugated paper block according to the curvature of the curve. The present invention can improve the accuracy of data collection of corrugated cardboard and reduce the error of subsequent warping degree calculation; at the same time, since the acquisition frequency of the 3D camera is very high, the system can receive 3D point cloud data in real time, and then grasp the warping degree of the current corrugated cardboard in real time; in addition, by timely feeding back the warping degree data to the operators, the production parameters can be adjusted in time to improve the qualified rate of corrugated cardboard.

Description

Technical Field

[0001] The present invention belongs to the technical field of corrugated board manufacturing, and particularly relates to a method, device and equipment for calculating the warping degree of corrugated board. Background Art

[0002] A corrugated board production line is a combination of equipment for producing corrugated board. When producing corrugated board, corresponding control needs to be carried out on each piece of equipment. If any link in the corrugated board production line has an abnormality, it will cause defects in the corrugated board, such as warping of the corrugated board. The specific degree of warping needs to be detected and calculated by a special instrument.

[0003] [[ID=lla]]In the prior art, multiple laser distance sensors are arranged on the corrugated board production line to detect the corrugated board and output multiple distance signals, and the multiple distance signals are analyzed to obtain information on whether the corrugated board is warped. However, this method has the following defects: First, since multiple distance sensors are installed at a certain interval, and there are slight errors in the installation height of each sensor, the subsequent detected distance signals also have errors and are greatly interfered by abnormal corrugated boards; Second, the existing analysis method analyzes the warping degree of the corrugation through the height difference between interval points, but since the cardboard height data between the sensors is not obtained, the curve of the real cardboard cannot be fitted; Third, if one or several of the sensors are damaged or affected by vibration interference, it will affect the accuracy of the warping degree calculation. Summary of the Invention

[0004] The purpose of the present invention is to provide a method, device and equipment for calculating the warping degree of corrugated board, which is used to solve at least one technical problem existing in the prior art.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] In the first aspect, the present invention provides a method for calculating the warping degree of corrugated board, including:

[0007] Receiving the first point cloud data of several corrugated boards, wherein the first point cloud data is collected by a 3D camera arranged at the board outlet of the corrugated board production line;

[0008] Extracting multiple groups of second point cloud data row by row from the first point cloud data, wherein each group of the second point cloud data corresponds to the cross-sectional data of one of the corrugated boards;

[0009] Determining the cutting points of the corrugated board according to the data distribution state of the second point cloud data, and determining the third point cloud data corresponding to each cut corrugated paper block according to the cutting points;

[0010] Perform curve fitting on the third point cloud data, and determine the warping degree of each corrugated paper block according to the curvature of the curve.

[0011] In a possible design, determining the cutting points of the corrugated board according to the data distribution state of the second point cloud data includes:

[0012] Detect the height difference between consecutive points in the second point cloud data. When the height difference between adjacent two points exceeds the height threshold, it is considered that the cutting point of the corrugated board is located between the adjacent two points.

[0013] In a possible design, before determining the cutting points of the corrugated board according to the data distribution state of the second point cloud data, the method further includes:

[0014] Preliminarily locate the position interval of the cutting points according to the board width and the number of cuts set by the production management system.

[0015] In a possible design, performing curve fitting on the third point cloud data, and determining the warping degree of each corrugated paper block according to the curvature of the curve includes:

[0016] Perform curve fitting on the third point cloud data by using the least squares method, and calculate the curvature of the midpoint of the curve;

[0017] When the curvature value of the midpoint of the curve is larger, the warping degree of the corrugated paper block is larger; when the curvature value of the midpoint of the curve is smaller, the warping degree of the corrugated paper block is smaller.

[0018] In a possible design, performing curve fitting on the third point cloud data, and determining the warping degree of each corrugated paper block according to the curvature of the curve includes:

[0019] Fit the third point cloud data into a circle, and calculate the radius of curvature of the circle according to the board width, the number of cuts, and the height data of the cross-section of the corresponding corrugated paper block;

[0020] When the radius of curvature value of the circle is larger, the warping degree of the corrugated paper block is smaller; when the radius of curvature value of the circle is smaller, the warping degree of the corrugated paper block is larger.

[0021] In a second aspect, the present invention provides a device for calculating the warping degree of a corrugated board, including:

[0022] A first point cloud data receiving module, configured to receive the first point cloud data of a plurality of corrugated boards, wherein the first point cloud data is collected by a 3D camera disposed at the outlet of the corrugated board production line;

[0023] A second point cloud data extraction module, configured to extract multiple groups of second point cloud data row by row from the first point cloud data, wherein each group of the second point cloud data corresponds to the cross-section data of one of the corrugated boards;

[0024] The third point cloud data determination module is configured to determine the cutting points of the corrugated board according to the data distribution state of the second point cloud data, and determine the third point cloud data corresponding to each cut corrugated paper block according to the cutting points;

[0025] The warping degree determination module is configured to perform curve fitting on the third point cloud data and determine the warping degree of each corrugated paper block according to the curvature of the curve.

[0026] In a possible design, when determining the cutting points of the corrugated board according to the data distribution state of the second point cloud data, the third point cloud data determination module is specifically configured to:

[0027] Detect the height difference between consecutive points in the second point cloud data. When the height difference between adjacent two points exceeds the height threshold, it is considered that the cutting point of the corrugated board is located between the adjacent two points.

[0028] In a possible design, the device further includes:

[0029] The cutting point positioning module is configured to perform a preliminary positioning on the position interval of the cutting points according to the cardboard width and the number of cuts set by the production management system.

[0030] In a possible design, when performing curve fitting on the third point cloud data and determining the warping degree of each corrugated paper block according to the curvature of the curve, the warping degree determination module is specifically configured to:

[0031] Perform curve fitting on the third point cloud data by using the least squares method and calculate the curvature of the midpoint of the curve;

[0032] When the curvature value of the midpoint of the curve is larger, the warping degree of the corrugated paper block is larger; when the curvature value of the midpoint of the curve is smaller, the warping degree of the corrugated paper block is smaller.

[0033] In a possible design, when performing curve fitting on the third point cloud data and determining the warping degree of each corrugated paper block according to the curvature of the curve, the warping degree determination module is specifically configured to:

[0034] Fit the third point cloud data into a circle, and calculate the radius of curvature of the circle according to the cardboard width, the number of cuts, and the height data of the cross-section of the corresponding corrugated paper block;

[0035] When the radius of curvature value of the circle is larger, the warping degree of the corrugated paper block is smaller; when the radius of curvature value of the circle is smaller, the warping degree of the corrugated paper block is larger.

[0036] In a third aspect, the present invention provides a computer device, including a memory, a processor, and a transceiver that are communicatively connected in sequence. Among them, the memory is used to store computer programs, the transceiver is used to send and receive messages, and the processor is used to read the computer programs and execute the corrugated cardboard warping degree calculation method described in any possible design of the first aspect.

[0037] In a fourth aspect, the present invention provides a computer-readable storage medium, on which instructions are stored. When the instructions run on a computer, they execute the corrugated cardboard warping degree calculation method described in any possible design of the first aspect.

[0038] In a fifth aspect, the present invention provides a computer program product containing instructions. When the instructions run on a computer, they cause the computer to execute the corrugated cardboard warping degree calculation method described in any possible design of the first aspect.

[0039] Beneficial effects:

[0040] The present invention receives the first point cloud data of a number of corrugated cardboard collected by a 3D camera; extracts multiple groups of second point cloud data row by row from the first point cloud data; determines the cutting points of the corrugated cardboard according to the data distribution state of the second point cloud data, and determines the third point cloud data corresponding to each cut corrugated paper block according to the cutting points; performs curve fitting on the third point cloud data, and determines the warping degree of each corrugated paper block according to the curvature of the curve. That is, the present invention collects the point cloud data of the corrugated cardboard through a high-precision 3D camera, thereby improving the accuracy of corrugated cardboard data collection and reducing the error of subsequent warping degree calculation; at the same time, since the acquisition frequency of the 3D camera is very high, the system can receive 3D point cloud data in real time, and then grasp the warping degree of the current corrugated cardboard in real time; in addition, by timely feeding back the warping degree data to the operators, the production parameters can be adjusted in time, improving the yield rate of corrugated cardboard. Description of the drawings

[0041] Figure 1 It is a flowchart of the corrugated cardboard warping degree calculation method in this embodiment. Detailed implementation manners

[0042] To make the objectives, technical solutions, and advantages of the embodiments of this specification clearer, the technical solutions in the embodiments of this specification will be clearly and completely described below in conjunction with the drawings in the embodiments of this specification. Obviously, the described embodiments are some, but not all, of the embodiments of this specification. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this specification without creative efforts shall fall within the protection scope of the present invention.

[0043] Embodiment

[0044] In order to solve the technical problem in the prior art that since multiple ranging sensors are installed at a certain interval, and there are slight errors in the installation heights of the respective sensors, resulting in errors in the subsequent detected distance signals and being greatly interfered by abnormal corrugated cardboard, the embodiment of the present application provides a method for calculating the warping degree of corrugated cardboard. This method collects the point cloud data of the corrugated cardboard through a high-precision 3D camera, thereby improving the accuracy of the data collection of the corrugated cardboard and reducing the error in the subsequent calculation of the warping degree; at the same time, since the acquisition frequency of the 3D camera is very high, the system can receive the 3D point cloud data in real time, and then grasp the warping degree of the current corrugated cardboard in real time; in addition, by timely feeding back the warping degree data to the operators, the production parameters can be adjusted in a timely manner, improving the yield rate of the corrugated cardboard.

[0045] As Figure 1 shown, in the first aspect, the embodiment provides a method for calculating the warping degree of corrugated cardboard, including but not limited to being implemented by steps S101 to S104, specifically as follows:

[0046] Step S101. Receive the first point cloud data of a plurality of corrugated cardboard, where the first point cloud data is collected by a 3D camera arranged at the cardboard outlet of the corrugated cardboard production line;

[0047] It should be noted that in this embodiment, the server receives the first point cloud data of a plurality of corrugated cardboard, and the 3D camera arranged at the cardboard outlet of the corrugated cardboard production line collects the point cloud data of the corrugated cardboard, and the controller arranged in the 3D camera uploads the point cloud data to the server; where, since multiple corrugated cardboard are stacked flat on the production line for cardboard outlet, the first point cloud data collected by the 3D camera at this time contains the cross-sectional point cloud data of multiple corrugated cardboard, and this cross-sectional point data is the height data relative to the conveyor belt.

[0048] Preferably, the 3D camera includes but not limited to a structured light 3D camera, a coded light 3D camera, a stereo vision 3D camera, a TOF 3D camera, etc., which is not limited here.

[0049] Step S102. Extract multiple groups of second point cloud data row by row from the first point cloud data, where each group of the second point cloud data corresponds to the cross-sectional data of one of the corrugated cardboard;

[0050] It should be noted that, since the first point cloud data contains cross-sectional point cloud data of several corrugated cardboards, if it is necessary to analyze and calculate the warpage of one of the corrugated cardboards, it is necessary to extract the cross-sectional point cloud data of each corrugated cardboard from the first point cloud data. Since the first point cloud data is arranged in a regular horizontal pattern, the second point cloud data can be extracted row by row from the first point cloud data to obtain the cross-sectional point cloud data of each corrugated cardboard.

[0051] Step S103. Determine the cutting points of the corrugated paperboard according to the data distribution state of the second point cloud data, and determine the third point cloud data corresponding to each cut corrugated paper block according to the cutting points;

[0052] In a specific implementation of step S103, determining the cutting points of the corrugated cardboard according to the data distribution state of the second point cloud data includes:

[0053] The height difference between consecutive points in the second point cloud data is detected. When the height difference between two adjacent points exceeds a height threshold, it is considered that the cutting point of the corrugated cardboard is located between the two adjacent points.

[0054] It should be noted that since the thickness of corrugated cardboard is basically uniform, for example, the thickness of three-layer corrugated cardboard and five-layer corrugated cardboard is usually set to less than 3 mm, the height threshold can be set to 3 mm. In addition, the point interval of the 3D camera is usually less than 0.5 mm, and the cutting interval of the cutter is also greater than 0.5 mm. Therefore, if the height difference between two adjacent points collected is greater than 3 mm, it is considered that the cutting point of the corrugated cardboard is located between the two adjacent points.

[0055] In a specific embodiment, before determining the cutting points of the corrugated cardboard according to the data distribution state of the second point cloud data, the method further includes:

[0056] According to the cardboard width and planing number set by the production management system, the position interval of the cutting point is preliminarily located, so that the position of the cutting point can be determined more accurately.

[0057] It should be noted that the cardboard width refers to the width of the entire corrugated cardboard before it is cut, and the planing number refers to the number of corrugated paper blocks that the production management system pre-sets to cut the entire corrugated cardboard into. For example, the planing number is set to 3, 4 or 5, etc., which is not limited here.

[0058] Step S104: Perform curve fitting on the third point cloud data, and determine the warping degree of each corrugated paper block according to the curvature of the curve.

[0059] In a specific implementation of step S104, curve fitting is performed on the third point cloud data, and the warping degree of each corrugated paper block is determined according to the curvature of the curve, including:

[0060] Step S1041. Use the least squares method to perform curve fitting on the third point cloud data and calculate the curvature of the midpoint of the curve;

[0061] It should be noted that the least squares method used in this embodiment is an existing algorithm, and its algorithm principle will not be specifically described here. In addition, the curvature of the midpoint of the curve can be calculated through existing curvature calculation formulas, and will not be elaborated here. Then, after the point cloud data of the cross-section of the corrugated paper block is fitted into a curve, the curvature of the curve can be used to characterize the warping degree of the corrugated paper block. Preferably, the warping degree of the corrugated paper block is characterized by the curvature of the midpoint of the curve, which can accurately reflect the warping degree of the corrugated paper block.

[0062] Step S1042. When the curvature value of the midpoint of the curve is larger, the warping degree of the corrugated paper block is larger; when the curvature value of the midpoint of the curve is smaller, the warping degree of the corrugated paper block is smaller.

[0063] In a specific implementation of step S104, curve fitting is performed on the third point cloud data, and the warping degree of each corrugated paper block is determined according to the curvature of the curve, including:

[0064] Fit the third point cloud data into a circle, and calculate the radius of curvature of the circle according to the width of the cardboard, the number of cuts, and the height data of the cross-section of the corresponding corrugated paper block;

[0065] Specifically, according to the width of the cardboard and the number of cuts, that is, dividing the width of the cardboard by the number of cuts, the width of each corrugated paper block can be obtained. Through the height data of the cross-section of the corrugated paper block and the width data of the paper block, the radius of curvature of the circle can be obtained.

[0066] When the value of the radius of curvature of the circle is larger, the warping degree of the corrugated paper block is smaller; when the value of the radius of curvature of the circle is smaller, the warping degree of the corrugated paper block is larger.

[0067] Based on the above - disclosed content, in this embodiment, the method includes: receiving the first point - cloud data of several corrugated boards collected by a 3D camera; extracting multiple groups of second point - cloud data row - by - row from the first point - cloud data; determining the cutting points of the corrugated board according to the data distribution state of the second point - cloud data, and determining the third point - cloud data corresponding to each cut corrugated paper block according to the cutting points; performing curve fitting on the third point - cloud data, and determining the warping degree of each corrugated paper block according to the curvature of the curve. That is, the present invention collects the point - cloud data of the corrugated board through a high - precision 3D camera, thereby improving the accuracy of corrugated board data collection and reducing the error in subsequent warping degree calculation; at the same time, since the acquisition frequency of the 3D camera is very high, the system can receive 3D point - cloud data in real time, and then grasp the warping degree of the current corrugated board in real time; in addition, by timely feeding back the warping degree data to the operators, the production parameters can be adjusted in time, improving the yield rate of corrugated boards.

[0068] In a second aspect, the present invention provides a device for calculating the warping degree of a corrugated board, including:

[0069] A first point - cloud data receiving module, configured to receive the first point - cloud data of several corrugated boards, where the first point - cloud data is collected by a 3D camera disposed at the board - output position of the corrugated board production line;

[0070] A second point - cloud data extraction module, configured to extract multiple groups of second point - cloud data row - by - row from the first point - cloud data, where each group of the second point - cloud data corresponds to the cross - sectional data of one of the corrugated boards;

[0071] A third point - cloud data determination module, configured to determine the cutting points of the corrugated board according to the data distribution state of the second point - cloud data, and determine the third point - cloud data corresponding to each cut corrugated paper block according to the cutting points;

[0072] A warping degree determination module, configured to perform curve fitting on the third point - cloud data and determine the warping degree of each corrugated paper block according to the curvature of the curve.

[0073] In a possible design, when determining the cutting points of the corrugated board according to the data distribution state of the second point - cloud data, the third point - cloud data determination module is specifically configured to:

[0074] Detect the height difference between consecutive points in the second point - cloud data. When the height difference between adjacent two points exceeds the height threshold, it is considered that the cutting point of the corrugated board is between the adjacent two points.

[0075] In a possible design, the device further includes:

[0076] A cutting - point positioning module, configured to preliminarily locate the position interval of the cutting points according to the board width and the number of cuts set by the production management system.

[0077] In a possible design, when performing curve fitting on the third point cloud data and determining the warping degree of each corrugated paper block according to the curvature of the curve, the warping degree determination module is specifically configured to:

[0078] Perform curve fitting on the third point cloud data by using the least squares method, and calculate the curvature of the midpoint of the curve;

[0079] When the curvature value of the midpoint of the curve is larger, the warping degree of the corrugated paper block is larger; when the curvature value of the midpoint of the curve is smaller, the warping degree of the corrugated paper block is smaller.

[0080] In a possible design, when performing curve fitting on the third point cloud data and determining the warping degree of each corrugated paper block according to the curvature of the curve, the warping degree determination module is specifically configured to:

[0081] Fit the third point cloud data into a circle, and calculate the radius of curvature of the circle according to the cardboard width, the number of planings, and the height data of the cross-section of the corresponding corrugated paper block;

[0082] When the radius of curvature value of the circle is larger, the warping degree of the corrugated paper block is smaller; when the radius of curvature value of the circle is smaller, the warping degree of the corrugated paper block is larger.

[0083] In a third aspect, the present invention provides a computer device, including a memory, a processor, and a transceiver that are communicatively connected in sequence, wherein the memory is used to store a computer program, the transceiver is used to send and receive messages, and the processor is used to read the computer program and execute the corrugated cardboard warping degree calculation method described in any possible design of the first aspect.

[0084] In a fourth aspect, the present invention provides a computer-readable storage medium, on which instructions are stored, and when the instructions are run on a computer, the corrugated cardboard warping degree calculation method described in any possible design of the first aspect is executed.

[0085] In a fifth aspect, the present invention provides a computer program product containing instructions, and when the instructions are run on a computer, the computer is made to execute the corrugated cardboard warping degree calculation method described in any possible design of the first aspect.

[0086] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for calculating the warping degree of corrugated cardboard, characterized in that, Including: Receiving first point cloud data of several corrugated cardboard sheets, wherein the first point cloud data is collected by a 3D camera arranged at the cardboard output of the corrugated cardboard production line; Extracting multiple groups of second point cloud data row by row from the first point cloud data, wherein each group of the second point cloud data corresponds to the cross-sectional data of one corrugated cardboard sheet; Determining the cutting points of the corrugated cardboard according to the data distribution state of the second point cloud data, and determining the third point cloud data corresponding to each cut corrugated paper block according to the cutting points. Wherein, determining the cutting points of the corrugated cardboard according to the data distribution state of the second point cloud data includes: detecting the height difference between consecutive points in the second point cloud data, and when the height difference between adjacent points exceeds the height threshold, it is considered that the cutting point of the corrugated cardboard is located between the adjacent points; Performing curve fitting on the third point cloud data and determining the warping degree of each corrugated paper block according to the curvature of the curve.

2. The method for calculating the warping degree of corrugated cardboard according to claim 1, wherein Before determining the cutting points of the corrugated cardboard according to the data distribution state of the second point cloud data, the method further includes: Pre - positioning the position interval of the cutting points according to the cardboard width and the number of cuts set by the production management system.

3. The method for calculating the warping degree of corrugated cardboard according to claim 1, characterized in that, Performing curve fitting on the third point cloud data and determining the warping degree of each corrugated paper block according to the curvature of the curve, including: Performing curve fitting on the third point cloud data by using the least - squares method and calculating the curvature of the mid - point of the curve; When the curvature value of the mid - point of the curve is larger, the warping degree of the corrugated paper block is larger; when the curvature value of the mid - point of the curve is smaller, the warping degree of the corrugated paper block is smaller.

4. The method for calculating the warping degree of corrugated cardboard according to claim 2, wherein, Performing curve fitting on the third point cloud data and determining the warping degree of each corrugated paper block according to the curvature of the curve, including: Fitting the third point cloud data into a circle, and calculating the radius of curvature of the circle according to the cardboard width, the number of cuts, and the height data of the cross - section of the corresponding corrugated paper block; When the radius of curvature value of the circle is larger, the warping degree of the corrugated paper block is smaller; when the radius of curvature value of the circle is smaller, the warping degree of the corrugated paper block is larger.

5. A corrugated cardboard warpage calculation device, characterized in that, Including: A first point cloud data receiving module for receiving first point cloud data of several corrugated cardboard sheets, wherein the first point cloud data is collected by a 3D camera arranged at the cardboard output of the corrugated cardboard production line; A second point cloud data extraction module for extracting multiple groups of second point cloud data row by row from the first point cloud data, wherein each group of the second point cloud data corresponds to the cross - sectional data of one corrugated cardboard sheet; A third point cloud data determining module for determining the cutting points of the corrugated cardboard according to the data distribution state of the second point cloud data, and determining the third point cloud data corresponding to each cut corrugated paper block according to the cutting points. Wherein, determining the cutting points of the corrugated cardboard according to the data distribution state of the second point cloud data includes: detecting the height difference between consecutive points in the second point cloud data, and when the height difference between adjacent points exceeds the height threshold, it is considered that the cutting point of the corrugated cardboard is located between the adjacent points; A warping degree determining module for performing curve fitting on the third point cloud data and determining the warping degree of each corrugated paper block according to the curvature of the curve.

6. The corrugated cardboard warping degree calculating device according to claim 5, wherein, When determining the cutting point of the corrugated cardboard according to the data distribution state of the second point cloud data, the third point cloud data determination module specifically is configured to: Detect the height difference between consecutive points in the second point cloud data. When the height difference between adjacent two points exceeds the height threshold, it is considered that the cutting point of the corrugated cardboard is located between the adjacent two points.

7. The corrugated cardboard warping degree calculation device according to claim 5, characterized in that When performing curve fitting on the third point cloud data and determining the warping degree of each corrugated paper block according to the curvature of the curve, the warping degree determination module specifically is configured to: Perform curve fitting on the third point cloud data by using the least square method and calculate the curvature of the midpoint of the curve; When the curvature value of the midpoint of the curve is larger, the warping degree of the corrugated paper block is larger; when the curvature value of the midpoint of the curve is smaller, the warping degree of the corrugated paper block is smaller.

8. A computer device, characterized in that, Comprising a memory, a processor and a transceiver that are communicatively connected in sequence, wherein the memory is used for storing a computer program, the transceiver is used for sending and receiving messages, and the processor is used for reading the computer program and executing the corrugated cardboard warping degree calculation method according to any one of claims 1-4.

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