A digital die-cutting machine cutting path recognition compensation method

Abstract

The present application relates to the field of digital die-cutting machine cutting, and relates to a digital die-cutting machine cutting path recognition compensation method. Before formal cutting, the die-cutting tool is controlled to move horizontally in an empty state to determine the deviation direction and deviation value of the mechanical horizontal and vertical directions of the cutting edge at each point, determine the overall horizontal offset of the cutting edge, and adjust the initial fixed position of the paper in combination with the horizontal deviation direction; during the cutting process, the deviation direction and deviation value of the corresponding mechanical horizontal deviation are obtained based on the real-time acquired instruction horizontal coordinates of the die-cuting machine cutting edge, the horizontal coordinate points of the cutting tool are corrected in real time in combination with the overall horizontal offset and the temperature of the digital die-cutting machine; the corresponding paper instruction vertical coordinates are compensated based on the mechanical vertical deviation direction and deviation value, the feedback deviation of each path point position on the paper that has completed cutting is obtained, the movement parameters of the cutting tool and the paper are adjusted in real time, and the die-cutting path compensation accuracy is improved.

Description

Technical Field

[0001] This invention relates to the field of digital die-cutting machine cutting, and specifically to a method for identifying and compensating cutting paths in a digital die-cutting machine. Background Technology

[0002] Digital die-cutting equipment is widely used in precision cutting and processing and has become a core automated processing equipment in post-press processing. As the precision of downstream consumer electronics and high-end printing products continues to increase, the market has placed stringent demands on the contour accuracy, dimensional tolerance, and batch processing consistency of die-cut products. The error suppression capability of the equipment under continuous high-speed production conditions directly determines the yield and production cost of the finished products.

[0003] Existing technologies, such as Chinese Patent Publication No. CN119036543A, disclose an error correction method and system for a die-cutting machine. This method involves arranging overlapping positioning data sequentially based on the acquisition time of monitoring parameters to construct overlapping positioning time-series coordinates; identifying abnormal overlapping positioning points and abnormal change trends based on these coordinates; tracing displacement, vibration, and temperature data of bearings and guide rails with the same time-series relationship to perform cumulative effect analysis and determine error factors; performing error tracking analysis on the error factors to determine compensation and correction strategies; and sending error correction reminder information.

[0004] However, the existing technology has the following problems: 1. The existing technology only outputs correction reminders based on the abnormal trend of the timing of the equipment transmission components. It does not consider the non-uniform distribution of mechanical deviations at each point of the horizontal stroke, the coupling relationship between the longitudinal deviation and the horizontal coordinate point, and only relies on offline static calibration parameters for unified correction. This leads to under-compensation or over-compensation in some parts of the plate. During the processing, dynamic time-varying errors such as tool wear and feed slippage continue to accumulate, and the die-cutting contour accuracy continues to deteriorate after long-term mass production.

[0005] 2. Existing technologies rely solely on monitoring data from guide rails and bearings to construct timing error factors for correction. They do not consider the slight deformation of the cutting material due to temperature rise in high-precision overlay or panel cutting scenarios. If this deformation is not corrected, the actual contact point will deviate from the theoretical path position as the material expands or contracts. Accumulated deformation errors will cause misalignment or overlap of adjacent graphic seams, directly affecting the cutting yield and processing quality. Summary of the Invention

[0006] This invention aims to address the shortcomings of existing technologies by providing a cutting path recognition and compensation method for digital die-cutting machines. The invention obtains the lateral and longitudinal deviations of each instruction coordinate point through idle traversal; adjusts the initial position of the paper based on the overall lateral deviation offset; combines temperature expansion compensation, point-by-point lateral deviation correction, and unidirectional longitudinal deviation compensation during cutting; and then superimposes the feedback deviation of the completed path to achieve closed-loop adjustment of cutting parameters.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: The present invention provides a cutting path recognition and compensation method for a digital die-cutting machine, comprising: before formal cutting, controlling the die-cutting tool to move laterally in an unloaded state, obtaining the actual coordinates corresponding to each command coordinate point during the movement, and determining the mechanical lateral and longitudinal deviation direction and deviation value of the cutting edge at each point.

[0008] The overall lateral offset of the blade is determined based on the mechanical lateral deviation value of the blade at each point, and the initial fixed position of the paper is adjusted in combination with the lateral deviation direction.

[0009] During the cutting process, the direction and value of the mechanical lateral deviation are obtained based on the command horizontal coordinate of the die-cutting machine blade in real time. The horizontal coordinate point of the blade is then corrected in real time by combining the overall lateral offset and the temperature of the digital die-cutting machine.

[0010] The compensated vertical coordinate of the paper instruction is obtained by compensating the mechanical longitudinal deviation direction and deviation value corresponding to the horizontal coordinate of the instruction based on the horizontal coordinate of the instruction on the die-cutting machine.

[0011] The system obtains the feedback deviation between the cut points on the paper and the command coordinates, and adjusts the movement parameters of the cutting tool and the paper in real time based on the feedback deviation.

[0012] Compared with the prior art, the present invention has the following beneficial effects: (1) Before formal cutting, the present invention controls the lateral movement of the die-cutting tool in an unloaded state, obtains the actual coordinates corresponding to each command coordinate point during the movement, and determines the mechanical lateral and longitudinal deviation direction and deviation value of the blade at each point. By providing a point-specific deviation basis for accurate compensation of the longitudinal coordinate, the composite trajectory blade tip deviates from the theoretical path.

[0013] (2) The present invention determines the overall lateral offset of the blade based on the mechanical lateral deviation value of the blade at each point, and adjusts the initial fixed position of the paper in combination with the lateral deviation direction. The pre-reference correction reduces the amount of computation for subsequent real-time dynamic compensation, reduces the computing load of the controller, and improves the motion response speed.

[0014] (3) In the cutting process, the present invention obtains the deviation direction and deviation value of the mechanical lateral deviation based on the command horizontal coordinate of the die-cutting machine blade in real time, and corrects the horizontal coordinate point of the blade in real time by combining the overall lateral offset and the temperature of the digital die-cutting machine, thereby eliminating the paper size deformation deviation caused by equipment temperature rise and ambient temperature fluctuation, improving the consistency of die-cutting size under different temperature conditions, and effectively improving the running stability of the cutting path and the positioning accuracy of the point.

[0015] (4) The present invention compensates the paper instruction vertical coordinate corresponding to the instruction horizontal coordinate based on the mechanical longitudinal deviation direction and deviation value corresponding to the instruction horizontal coordinate of the die-cutting machine blade, and obtains the compensated instruction vertical coordinate. It accurately matches the actual longitudinal offset law of the blade tip, cancels the longitudinal position deviation of the blade tip from the material feeding end, and the cutting trajectory fits the theoretical design path.

[0016] (5) This invention obtains the feedback deviation between the path points that have been cut on the paper and the command coordinates, and adjusts the movement parameters of the cutting tool and the paper in real time based on the feedback deviation, thereby improving the accuracy of die-cutting point correction in continuous processing and improving the stability of cutting dimensions throughout the batch production process. Attached Figure Description

[0017] 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 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.

[0018] Figure 1 This is a schematic diagram of the method steps of the present invention;

[0019] Figure 2 This is a schematic diagram illustrating the specific steps involved in real-time correction of the tool's horizontal coordinate point in this invention.

[0020] Figure 3 This is a schematic diagram of the real-time overlay adjustment steps in this invention. Detailed Implementation

[0021] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. Furthermore, it should be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale.

[0022] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use. Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification.

[0023] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0024] Please see Figure 1 As shown, the present invention provides a cutting path recognition and compensation method for a digital die-cutting machine, including: S1, before formal cutting, controlling the die-cutting tool to move laterally in an unloaded state, obtaining the actual coordinates corresponding to each command coordinate point during the movement, and determining the mechanical lateral and longitudinal deviation direction and deviation value of the blade at each point.

[0025] Considering that if the non-uniform fluctuation of deviations at various points in the lateral travel is ignored and the characteristics of the coupling between longitudinal deviation and horizontal coordinate points are ignored, relying solely on uniform offset correction will cause local undercompensation or overcompensation of the layout, and it is impossible to quantify the differentiated longitudinal offset corresponding to different horizontal coordinates; at the same time, offline calibration lacks precise image vision positioning methods, and simply relying on the difference in motor command cannot separate the true deviation of the cutting tip caused by the inherent mechanical clearance, making it difficult to establish a dedicated deviation database for each point.

[0026] Based on this, the specific implementation steps of S1 include: S11, driving the die-cutting tool to traverse each command coordinate point laterally in an unloaded state, and acquiring the position image of the cutting edge at each command coordinate point through an image acquisition device. It should be noted that, due to the unavoidable slight angle between the optical axis and the normal of the cutting platform during the mechanical installation of the CCD industrial camera, the relationship between the image coordinate system and the machine coordinate system is not a simple linear scaling relationship. Directly using linear mapping will not eliminate the trapezoidal distortion caused by perspective projection and the nonlinear errors caused by lens radial distortion.

[0027] In a specific embodiment of the present invention, firstly, a CCD industrial camera fixedly installed below the crossbeam of the die-cutting machine is used to acquire real-time images of the blade's position. The optical axis of the CCD industrial camera is perpendicular to the cutting platform plane, and its field of view covers the maximum lateral movement of the blade. Then, a checkerboard calibration plate is used for camera calibration: the checkerboard calibration plate is placed flat on the working surface of the cutting platform, so that the plane of the calibration plate coincides with the plane of the cutting platform. The die-cutting tool is controlled to move to several preset corner positions on the calibration plate, and the coordinate values ​​of each corner point in the machine coordinate system are recorded. At the same time, images of each corner point are acquired by the CCD camera, and the pixel coordinates of each corner point in the image pixel coordinate system are extracted. A homography transformation matrix H between the two sets of coordinates is established, such that any machine coordinate (X, Y) satisfies the following equation: .

[0028] Where (u, v) represent pixel coordinates, the homography transformation matrix is ​​calibrated by preset corner point positions and corresponding coordinate values ​​of each corner point in the machine coordinate system. After calibration, the pixel coordinates of the blade tip extracted from the image are all transformed to the actual coordinate values ​​in the machine coordinate system through the homography transformation matrix.

[0029] S12. Perform edge extraction and contour recognition on the blade position image to extract the actual blade tip position coordinates. Calculate the difference between the actual blade tip position coordinates and the current command coordinates to obtain the lateral and longitudinal deviation values. The specific method for extracting the actual blade tip position coordinates from the blade position image is as follows: Perform contour tracking on the binarized edge image obtained by Canny edge detection to obtain the coordinates of each edge point of the blade contour; use the least squares method to fit two straight lines of the blade contour, and take the intersection of the two straight lines as the sub-pixel level position coordinates of the blade tip; if two straight lines cannot be fitted, take the point with the maximum curvature in the blade contour as the position coordinates of the blade tip. This is existing technology and will not be described in detail in this invention. In addition, it should be noted that during the no-load traversal calibration stage, the die-cutting tool only moves laterally and does not feed longitudinally. Therefore, the command ordinate of the current command coordinate point is 0. The longitudinal deviation mapping table established during the no-load traversal stage records the fixed offset of the tool tip in the longitudinal direction (Y-axis) at each horizontal coordinate point. This offset is superimposed on each command ordinate during the subsequent formal cutting process.

[0030] S13. When the deviation value is positive, its deviation direction is recorded as the positive direction; when the deviation value is negative, its deviation direction is recorded as the negative direction. In a preferred embodiment of the invention, facing the printer's paper output port, with the leftmost end of the cutting blade as the origin, the direction of the cutting blade's movement is taken as the X-axis, with the rightward direction as the positive direction. The direction on the same horizontal plane as the horizontal axis and perpendicular to it is taken as the Y-axis, with the direction away from the printer's paper output port as the positive direction. When the calculated deviation value is positive, it indicates that the actual position of the blade deviates from the command coordinate point along the positive direction of the X-axis or Y-axis, and its deviation direction is recorded as the positive direction; when the deviation value is negative, it indicates that it deviates along the negative direction of the X-axis or Y-axis, and its deviation direction is recorded as the negative direction.

[0031] S14. After the traversal is complete, a lateral deviation mapping table and a longitudinal deviation mapping table are generated, indexed by the command coordinates. These tables record the lateral deviation direction and value, and the longitudinal deviation direction and value, respectively, for each command coordinate point. During the lateral traversal of each command coordinate point, an equal-interval sampling strategy is used, with the sampling interval between two adjacent command coordinate points set to 0.5 mm. If the actual mechanical structure exhibits repetitive positioning deviations, the tool edge position image is repeatedly acquired 5 times at each sampling coordinate point, and the arithmetic mean of the deviation values ​​obtained from the 5 measurements is calculated as the final lateral and longitudinal deviation values ​​for that point.

[0032] Before the actual cutting, this invention controls the lateral movement of the die-cutting tool in an unloaded state, obtains the actual coordinates of each command coordinate point during the movement, and determines the mechanical lateral and longitudinal deviation direction and value of the cutting edge at each point. This provides a point-specific deviation basis for accurate compensation of the longitudinal coordinate, avoiding deviation of the synthesized trajectory cutting tip from the theoretical path.

[0033] S2. Determine the overall lateral offset of the blade and adjust the initial fixed position of the paper.

[0034] Considering the systematic lateral offset in the transmission and guide rail assembly of the whole machine, directly compensating each point individually would greatly increase the real-time computing load of the controller and delay the motion response; and since there is no unified reference correction point for the paper, the overall offset would cause the centering of the cutting pattern on the whole page to be misaligned, which cannot offset the uniform deviation of the whole machine from the source. Therefore, this invention realizes the adjustment of the initial fixed position of the paper by calculating the overall lateral offset.

[0035] Based on this, the specific implementation steps of S2 include: S21, determining the overall lateral offset of the cutting edge based on the mechanical lateral deviation values ​​of the cutting edge at each point. The specific implementation steps include: S211, obtaining the lateral deviation values ​​corresponding to each command coordinate point of the cutting edge, and vector-summing the lateral deviation values ​​corresponding to each command coordinate point to obtain a vector sum.

[0036] S212. The ratio of the vector sum to the total number of command x-coordinate points is recorded as the overall horizontal offset.

[0037] S22. Adjust the initial fixed position of the paper based on the lateral deviation direction. The specific implementation steps include: S221. Obtain the initial fixed position of the paper to be cut in the current batch from the digital die-cutting machine's cutting work background database, keep the vertical coordinate unchanged, and record the midpoint of the horizontal coordinate of the paper as the center fixed point.

[0038] S222. If the overall lateral offset is negative, the paper's center fixed point is moved in the negative direction by the corresponding overall lateral offset. It should be noted that a negative overall lateral offset indicates that the actual position of the blade tip is offset in the negative X-axis direction relative to the commanded position. To align the point to be processed on the paper with the actual blade tip, the paper needs to be moved in the same negative direction by the absolute value of this offset, i.e., the direction of movement must be the same as the direction of deviation, thus achieving positional overlap. If the deviation is positive, the paper moves in the same positive direction.

[0039] S223. If the overall horizontal offset is positive, then control the paper center fixed point to move in the positive direction by the corresponding overall horizontal offset.

[0040] This invention determines the overall lateral offset of the blade based on the mechanical lateral deviation value of the blade at each point, and adjusts the initial fixed position of the paper in combination with the lateral deviation direction. The pre-reference correction reduces the amount of computation for subsequent real-time dynamic compensation, reduces the computing load on the controller, and improves the motion response speed.

[0041] S3. During the cutting process, the deviation direction and value of the corresponding mechanical lateral deviation are obtained based on the command horizontal coordinate of the die-cutting machine blade in real time. The horizontal coordinate point of the blade is corrected in real time in combination with the overall lateral offset and the temperature of the digital die-cutting machine.

[0042] Considering that paper is a temperature-sensitive substrate, the long-term temperature rise of the equipment and the temperature fluctuation of the workshop environment will cause the paper to expand and contract. The existing technology has not built a quantitative compensation model for temperature. When the temperature changes, the compensation parameters are prone to step jump, causing the tool feed to jitter. At the same time, relying solely on the offset of the whole machine cannot eliminate the local fluctuation deviation at various positions of the horizontal axis. The superposition of the two errors continuously reduces the consistency of the horizontal cutting size.

[0043] Based on this, such as Figure 2 As shown, the specific implementation steps of S3 include: S31, obtaining the temperature of the current digital die-cutting machine, and obtaining the paper expansion coefficient from the expansion coefficient reference table corresponding to different temperatures of the current batch of cut paper material based on the temperature. The method for obtaining the expansion coefficient includes: S311, cutting standard-sized samples from each batch of cut paper material and placing the samples in a temperature-controlled chamber.

[0044] S312. The sample is heated from the initial room temperature to the preset termination temperature at a preset heating rate. During the heating process, the length of the sample at each temperature is continuously collected by a displacement sensor. For example, in a specific embodiment of the present invention, the heating rate of the temperature control chamber is set to 1℃ / min, where the initial temperature is 23℃ and the termination temperature is set to 70℃. The implementer may also set other specific values.

[0045] S313. Record the ratio of the length of the sample at each temperature to the initial length as the expansion coefficient at the corresponding temperature, and obtain a table of expansion coefficients corresponding to different temperatures for each batch of cut paper materials.

[0046] S314. Obtain the real-time temperature of the current digital die-cutting machine. Based on the real-time temperature, query the expansion coefficient reference table for the current batch of paper materials to match the expansion coefficient corresponding to the current temperature. Specifically, during the actual cutting process, a platinum resistance temperature sensor is fixedly installed below the cutting platform near the paper feed path, acquiring the temperature value of the working area of ​​the digital die-cutting machine in real time at a sampling frequency of once per second. The sliding average of the most recent 10 sampling values ​​is taken as the current real-time temperature to eliminate the impact of instantaneous temperature fluctuations on compensation accuracy. The current temperature value is read before each cutting path begins to calculate the current paper expansion coefficient. Furthermore, if the current real-time temperature is lower than the minimum recorded temperature (23℃) in the reference table, the expansion coefficient corresponding to the minimum recorded temperature is directly used; if the current real-time temperature is higher than the maximum recorded temperature (70℃) in the reference table, a temperature over-limit warning is issued, and the expansion coefficient corresponding to the maximum recorded temperature is used as an approximation, while simultaneously prompting the operator to check the equipment temperature rise status.

[0047] S315. If the current temperature is between two temperatures, then perform linear interpolation on the expansion coefficients corresponding to the two adjacent temperature intervals, and record the interpolation result as the current paper expansion coefficient.

[0048] S32. Using the center fixed point as a reference, perform initial correction on the horizontal coordinates of each instruction according to the paper expansion coefficient. The specific implementation steps are as follows: obtain the horizontal coordinate of the paper's center fixed point, obtain the difference between the horizontal coordinate of each instruction and the horizontal coordinate of the center fixed point, multiply the difference by the expansion coefficient and record it as the expansion correction value, and record the sum of the expansion correction value of each instruction and the horizontal coordinate of the center fixed point as the initial corrected horizontal coordinates of each instruction.

[0049] S33. Based on the horizontal coordinates of each instruction after the initial correction, match the corresponding horizontal deviation direction and deviation value from the horizontal deviation mapping table, and record it as the current actual deviation of the cutting edge.

[0050] S34. The difference between the overall lateral offset and the actual deviation of the current cutting edge is recorded as the real-time correction amount, and the sum of the horizontal coordinate of the current command coordinate point and the real-time correction amount is recorded as the final corrected command horizontal coordinate. This achieves the use of the overall offset as a reference rather than the final correction amount, and on this basis, the residual between the point-by-point deviation and the overall offset is superimposed for secondary correction, thereby eliminating both systematic deviation and local fluctuation deviation, making the lateral cutting accuracy of each horizontal coordinate point tend to be consistent.

[0051] During the cutting process, this invention obtains the deviation direction and value of the corresponding mechanical lateral deviation based on the command horizontal coordinate of the die-cutting machine blade in real time. Combined with the overall lateral offset and the temperature of the digital die-cutting machine, the horizontal coordinate point of the blade is corrected in real time. This eliminates the paper size deformation deviation caused by equipment temperature rise and ambient temperature fluctuations, improves the consistency of die-cutting size under different temperature conditions, and effectively improves the running stability of the cutting path and the positioning accuracy.

[0052] S4. Based on the mechanical longitudinal deviation direction and deviation value corresponding to the command horizontal coordinate where the die-cutting machine blade is located, the paper command vertical coordinate corresponding to the command horizontal coordinate is compensated to obtain the compensated command vertical coordinate.

[0053] Considering that ignoring the significant differences in the longitudinal offset of the blade tip at different horizontal coordinates under the same conveying time, the decoupling compensation of horizontal and vertical deviations will cause the two-dimensional synthetic trajectory to continuously deviate from the theoretical contour, resulting in prominent problems such as misalignment of the seams and out-of-tolerance of irregular die-cut graphics. This invention compensates for the vertical coordinate of the paper instruction corresponding to the horizontal coordinate of the instruction.

[0054] Based on this, the step of obtaining the compensated instruction vertical coordinate includes: S41, based on the real-time acquisition of the instruction horizontal coordinate of the die-cutting machine blade, matching the corresponding longitudinal deviation direction and deviation value from the longitudinal deviation mapping table, and recording it as the current blade longitudinal deviation.

[0055] S42. Obtain the paper instruction vertical coordinate corresponding to the current instruction position, and record the algebraic sum of the instruction vertical coordinate and the current blade longitudinal deviation value as the compensated instruction vertical coordinate.

[0056] S43. Control the longitudinal feeding mechanism of the paper to move longitudinally according to the compensated instruction longitudinal coordinate.

[0057] This invention compensates the paper instruction ordinate corresponding to the instruction ordinate based on the mechanical longitudinal deviation direction and deviation value corresponding to the instruction abscissa of the die-cutting machine blade, thereby obtaining the compensated instruction ordinate. This accurately matches the actual longitudinal offset law of the blade tip, cancels the longitudinal position deviation of the blade tip from the material feeding end, and the cutting trajectory conforms to the theoretically designed path.

[0058] S5. Obtain feedback deviation and adjust the movement parameters of the cutting tool and paper in real time.

[0059] Considering that offline no-load calibration can only correct the initial static mechanical error when the machine is turned on, it cannot adapt to the dynamic time-varying error caused by tool wear during continuous processing; the lack of a closed-loop iteration mechanism will cause the error to accumulate continuously in the later stage of mass production, and can only be adjusted manually by stopping the machine, which reduces production efficiency and increases material loss.

[0060] Based on this, the specific implementation steps of S5 include: S51, obtaining the feedback deviation between the completed cutting path points on the paper and the command coordinates. The specific implementation steps include: S511, during the cutting process, acquiring real-time images of the actual positions of the completed cutting path points on the paper using an image acquisition device. A global shutter camera combined with a stroboscopic light source is used for short-exposure acquisition, with an exposure time not exceeding 100 microseconds, to freeze the paper's movement state and eliminate image blurring caused by continuous paper movement. If the current path is the first path of this cutting task, and the feedback deviation sequence has not yet stored any historical data, then the feedback overlay operation is not performed; only the command coordinates corrected by steps S3 and S4 are output as the final execution coordinates.

[0061] S512. Perform edge extraction and contour recognition on the actual position image to extract the actual blade tip trajectory coordinates of the completed cutting path. In a specific embodiment of the present invention, the actual blade tip trajectory coordinates of the past 10 historical acquisition points of the current cutting point are obtained.

[0062] S513. Calculate the difference between the actual tool tip trajectory coordinates and the final corrected command horizontal coordinates and the compensated command vertical coordinates to obtain the lateral feedback deviation value and longitudinal feedback deviation value of each path point and the corresponding deviation direction.

[0063] S514. Store the lateral feedback deviation value and longitudinal feedback deviation value of each path point into the lateral feedback deviation sequence and the longitudinal feedback deviation sequence, respectively.

[0064] S52. Based on feedback deviation, the movement parameters of the cutting tool and paper are adjusted in real time. For example... Figure 3 As shown, the specific implementation steps include: S521, obtaining the instruction abscissa of the current cutting point, obtaining the abscissa value based on the abscissa sequence, and recording the sum of the opposite of the abscissa value and the current final corrected instruction abscissa as the superimposed final instruction abscissa.

[0065] S522. Obtain the longitudinal feedback deviation value corresponding to the current instruction horizontal coordinate based on the longitudinal feedback deviation sequence, and record the sum of the negative number of the longitudinal feedback deviation value and the current compensated instruction vertical coordinate as the final instruction vertical coordinate after superposition. In a preferred embodiment of the present invention, the average deviation in the horizontal feedback deviation sequence is recorded as the horizontal feedback deviation value, and the average deviation in the longitudinal feedback deviation sequence is recorded as the longitudinal feedback deviation value.

[0066] It should be noted that if the feedback deviation sequence has not yet stored any path data when the first cutting path is being executed, then no feedback superposition will be performed, and the final corrected instruction x-coordinate and the compensated instruction y-coordinate will be used as the final instruction coordinates.

[0067] S523. Control the cutting tool to move according to the horizontal coordinate of the superimposed final instruction, and control the paper to feed longitudinally according to the vertical coordinate of the superimposed final instruction.

[0068] S524. After the current path is cut, update the feedback deviation value of the current path to the horizontal feedback deviation sequence and the vertical feedback deviation sequence for superposition adjustment of the next path.

[0069] This invention improves the accuracy of die-cutting point correction in continuous processing by obtaining the feedback deviation between the cut points on the paper and the command coordinates, and by adjusting the movement parameters of the cutting tool and the paper in real time based on the feedback deviation, thereby improving the stability of the cutting dimensions throughout the batch production process.

[0070] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product.

[0071] Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0072] In addition, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0073] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0074] Finally, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for identifying and compensating cutting paths in a digital die-cutting machine, characterized in that, include: Before the actual cutting, the die-cutting tool is controlled to move laterally under no-load conditions. The actual coordinates of each command coordinate point during the movement are obtained to determine the mechanical lateral and longitudinal deviation direction and value of the cutting edge at each point. The overall lateral offset of the blade is determined based on the mechanical lateral deviation value of the blade at each point, and the initial fixed position of the paper is adjusted in combination with the lateral deviation direction. During the cutting process, the direction and value of the mechanical lateral deviation are obtained based on the command horizontal coordinate of the die-cutting machine blade in real time. The horizontal coordinate point of the blade is then corrected in real time in combination with the overall lateral offset and the temperature of the digital die-cutting machine. The corrected instruction ordinate is obtained by compensating the paper instruction ordinate corresponding to the instruction ordinate based on the mechanical longitudinal deviation direction and deviation value corresponding to the instruction abscissa of the die-cutting machine blade. The system obtains the feedback deviation between the cut points on the paper and the command coordinates, and adjusts the movement parameters of the cutting tool and the paper in real time based on the feedback deviation. The method for obtaining the feedback deviation includes: During the cutting process, the actual position images of each path point on the paper that has been cut are acquired in real time through an image acquisition device. Edge extraction and contour recognition are performed on the actual position image to extract the actual blade tip trajectory coordinates of the completed cutting path; The difference between the actual tool tip trajectory coordinates and the final corrected command horizontal coordinates and the compensated command vertical coordinates is calculated to obtain the lateral feedback deviation value and longitudinal feedback deviation value of each path point and the corresponding deviation direction. Store the lateral feedback deviation value and longitudinal feedback deviation value of each path point into the lateral feedback deviation sequence and the longitudinal feedback deviation sequence, respectively. The specific steps of the real-time overlay adjustment include: Obtain the command x-coordinate of the current cutting point, obtain the lateral feedback deviation value based on the lateral feedback deviation sequence, and record the sum of the opposite of the lateral feedback deviation value and the current final corrected command x-coordinate as the superimposed final command x-coordinate. Based on the longitudinal feedback deviation sequence, the longitudinal feedback deviation value corresponding to the current instruction horizontal coordinate is obtained, and the sum of the opposite of the longitudinal feedback deviation value and the current compensated instruction vertical coordinate is recorded as the final instruction vertical coordinate after superposition. The cutting tool is controlled to move according to the horizontal coordinate of the superimposed final instruction, and the paper is controlled to feed longitudinally according to the vertical coordinate of the superimposed final instruction. After the current path is cut, the feedback deviation value of the current path is updated in the horizontal feedback deviation sequence and the vertical feedback deviation sequence for superposition adjustment of the next path.

2. The cutting path recognition and compensation method for a digital die-cutting machine according to claim 1, characterized in that, The methods for obtaining the direction and value of the mechanical lateral and longitudinal deviations of the cutting edge at various points include: The die-cutting cutter is driven to traverse each command coordinate point in the horizontal direction under no-load conditions. At each command coordinate point, the position image of the cutter edge is acquired by the image acquisition device. Edge extraction and contour recognition are performed on the position image of the cutting edge to extract the actual cutting tip position coordinates. The difference between the actual cutting tip position coordinates and the current command coordinates is calculated to obtain the lateral deviation value and the longitudinal deviation value. When the deviation value is positive, its direction is recorded as positive; when the deviation value is negative, its direction is recorded as negative. After the traversal is completed, a horizontal deviation mapping table and a vertical deviation mapping table are generated with the command coordinates as the index, recording the horizontal deviation direction and deviation value, and the vertical deviation direction and deviation value corresponding to each command coordinate point, respectively.

3. The cutting path recognition and compensation method for a digital die-cutting machine according to claim 1, characterized in that, The method for obtaining the overall lateral offset of the cutting edge includes: Obtain the lateral deviation value corresponding to each command coordinate point in the lateral direction of the blade, and add the lateral deviation values ​​corresponding to each command coordinate point vector by vector to obtain the vector sum; The ratio of the vector sum to the total number of command x-coordinate points is denoted as the overall horizontal offset.

4. The cutting path recognition and compensation method for a digital die-cutting machine according to claim 1, characterized in that, The specific steps for adjusting the initial fixed position of the paper include: The initial fixed position of the paper to be cut in the current batch is obtained from the background database of the digital die-cutting machine. Keeping the vertical coordinate unchanged, the midpoint of the horizontal coordinate of the paper is recorded as the center fixed point. If the overall horizontal offset is negative, then control the paper center fixed point to move in the negative direction by the corresponding overall horizontal offset. If the overall horizontal offset is positive, then the paper's center fixed point is moved in the positive direction by the corresponding overall horizontal offset.

5. The cutting path recognition and compensation method for a digital die-cutting machine according to claim 4, characterized in that, The specific steps for real-time correction of the tool's transverse coordinate point include: Get the current temperature of the digital die-cutting machine, and based on the temperature, obtain the paper expansion coefficient from the expansion coefficient reference table corresponding to different temperatures of the paper material being cut in the current batch; Using the center fixed point as a reference, the horizontal coordinates of each instruction are initially corrected according to the paper expansion coefficient. Based on the horizontal coordinates of each command after the initial correction, the corresponding horizontal deviation direction and deviation value are matched from the horizontal deviation mapping table and recorded as the current actual deviation of the cutting edge. The difference between the overall lateral offset and the actual deviation of the current cutting edge is recorded as the real-time correction amount, and the sum of the horizontal coordinate of the current command coordinate point and the real-time correction amount is recorded as the final corrected horizontal coordinate of the command.

6. The cutting path recognition and compensation method for a digital die-cutting machine according to claim 5, characterized in that, The method for obtaining the expansion coefficient includes: Standard-sized samples were cut from each batch of paper material and placed in a temperature-controlled chamber. The sample is heated from the initial room temperature to the preset termination temperature at a preset heating rate. During the heating process, the length of the sample at each temperature is continuously collected by a displacement sensor. The ratio of the length of the sample at each temperature to the initial length is recorded as the coefficient of thermal expansion at the corresponding temperature, thus obtaining a table of coefficients of thermal expansion for different batches of paper cutting materials at different temperatures. Get the real-time temperature of the current digital die-cutting machine, and look up the expansion coefficient reference table of the paper material to be cut in the current batch based on the real-time temperature to match the expansion coefficient of the current temperature; If the current temperature is between two temperatures, then the expansion coefficients corresponding to the two adjacent temperature ranges are linearly interpolated, and the interpolation result is recorded as the current paper expansion coefficient.

7. The cutting path recognition and compensation method for a digital die-cutting machine according to claim 6, characterized in that, The specific steps for the initial correction are as follows: Obtain the x-coordinate of the fixed center point of the paper, obtain the difference between the x-coordinate of each instruction coordinate and the x-coordinate of the fixed center point, multiply the difference by the expansion coefficient and record it as the expansion correction value, and record the sum of the expansion correction value of each instruction coordinate and the x-coordinate of the fixed center point as the initial corrected x-coordinate of each instruction.

8. The cutting path recognition and compensation method for a digital die-cutting machine according to claim 1, characterized in that, The steps for obtaining the compensated command ordinate include: Based on the real-time acquisition of the command horizontal coordinate of the current position of the die-cutting machine blade, the corresponding longitudinal deviation direction and deviation value are matched from the longitudinal deviation mapping table and recorded as the current blade longitudinal deviation. Obtain the paper instruction ordinate corresponding to the current instruction position, and record the algebraic sum of the instruction ordinate and the current blade longitudinal deviation value as the compensated instruction ordinate. The longitudinal feeding mechanism of the paper is controlled to move longitudinally according to the compensated longitudinal coordinate.

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