Time-varying parameter self-tuning multicolor printing synchronous control system

Abstract

The invention relates to the technical field of adaptive control systems, and discloses a time-varying parameter self-tuning multicolor printing synchronous control system, which comprises a data acquisition module, a decision module, a compensation module, a control instruction module and an execution module, wherein the data acquisition module is used for acquiring state parameters of each color cell; the decision module is used for identifying a target color group needing to be compensated and determining the compensation amount of the target color group and a decoupling mode between the color groups; the compensation module is used for dynamically constructing a decoupling compensation matrix and calculating the compensation amount of a non-target color group based on the decoupling compensation matrix; the control instruction module is used for mapping the compensation quantity of each color group into the adjusting quantity of the working parameters and generating a control instruction; and the execution module is used for executing the control instruction and driving the working parameters of each color cell to be adjusted. The synchronization precision and stability of the multi-color printing system are improved, and the problem of coupling interference existing in the industry for a long time is solved.

Description

Technical Field

[0001] This application relates to the technical field of adaptive control systems, and particularly to a multi-color printing synchronization control system with time-varying parameter self-tuning. Background Art

[0002] A multi-color printing system is a highly coupled dynamic system, where each color unit affects each other through mechanical transmission chains and material tensions. When the parameters of a certain color unit (such as speed, tension or pressure) change, its influence will be transmitted to adjacent color units through the mechanical structure or materials, resulting in a decrease in the stability of the overall system. This coupling effect makes it difficult for traditional fixed-parameter control methods to achieve long-term stable high-precision printing.

[0003] In the prior art, there are significant drawbacks in multi-color printing synchronization control systems. Most existing systems use the PID control algorithm to adjust the servo motors of each color unit to maintain phase and tension stability. However, the parameters of the PID controller are usually fixed and cannot adapt to disturbances such as changes in material properties, environmental interference, and mechanical wear. The elastic moduli and friction coefficients of different printing substrates (such as paper, plastic film) vary greatly, and it is difficult for fixed PID parameters to take into account all working conditions. Factors such as changes in workshop temperature and humidity, and fluctuations in ink viscosity will affect the dynamic characteristics of the system, resulting in a decline in control performance. After long-term operation, problems such as gear clearances and belt slack in the transmission system will change the system response characteristics, rendering the original control parameters ineffective.

[0004] Some advanced equipment adopts a decoupling control strategy to reduce the mutual interference between color units. For example, feedforward compensation based on the tension transfer model or disturbance observer (DOB) technology. However, the existing decoupling methods have the following problems: Most decoupling models are based on linear approximations, while the coupling relationships in actual printing systems have significant non-linear characteristics, such as sudden changes in tension and ink viscosity effects. Existing methods usually use fixed decoupling coefficients and cannot dynamically adjust the decoupling strategy according to working conditions such as material properties and printing speed. Parameters such as phase, tension, and ink viscosity affect each other, but existing decoupling methods often only target a single variable (such as tension or phase) and lack the ability of global optimization.

[0005] The patent application with the publication number CN105116823A discloses a multi-color screen printing control system based on MODBUS, which includes a touch screen. The touch screen is connected to the COM1 port of the master station PLC through the RS232 serial port. The master station PLC controls a servo driver, and then controls the servo motor for longitudinal material feeding. At the same time, the master PLC communicates with each slave station PLC through the RS485 port. In the multi-PLC control system, to achieve coordinated control, the PLCs are connected using a master-slave network, that is, one PLC is selected as the master station, and the rest are slave stations. The master station manages the slave stations and initiates communication. The slave stations accept management and respond to communication. This technical solution is easy to implement centralized management and monitoring, has high security, and is more suitable as a control network and device network.

[0006] The patent application with the publication number CN109683481A discloses a method for controlling the lateral registration of a shaftless intaglio printing press. First, according to the printing principle and physical laws of the shaftless multi-color intaglio printing press, a non-linear model of the lateral registration system of the shaftless multi-color intaglio printing press is established; then, the perturbation method and the micro-element method are used to linearize the non-linear model, and a linear model of the lateral registration system of the shaftless multi-color intaglio printing press is derived; finally, according to the linear model, a decoupling control method for the multi-color lateral registration system based on feedforward control and active disturbance rejection control is designed. This technical solution is simple and reliable, has a good inhibitory effect on various interferences, and has wide applicability; compared with the traditional PID control, under the same conditions, the fluctuations and persistence of the registration error are significantly reduced, and it can have a good inhibitory effect on the interference of tension changes.

[0007] The above patents all have the problems raised in this background technology: they cannot dynamically adjust the decoupling strategy according to working conditions such as material properties and printing speed.

[0008] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of this application, and should not be regarded as an admission or any form of suggestion that this information constitutes the prior art already known to those of ordinary skill in the art. Summary of the Invention

[0009] The technical problem to be solved by this application is to overcome the defects of the prior art, provide a multi-color printing synchronization control system with time-varying parameter self-tuning, improve the synchronization accuracy and stability of the multi-color printing system, and solve the problem of coupling interference that has long existed in the industry.

[0010] To solve the above technical problems, this application provides the following technical solutions:

[0011] A multi-color printing synchronization control system with time-varying parameter self-tuning, including a data acquisition module, a decision-making module, a compensation module, a control instruction module, and an execution module; among them:

[0012] The data acquisition module is used to acquire the state parameters of each color group; the state parameters include phase, tension, and ink viscosity;

[0013] The decision-making module, based on the state parameters of each color group, identifies the target color group that needs compensation, and determines the compensation amount of the target color group and the decoupling mode between color groups;

[0014] The compensation module dynamically constructs a decoupling compensation matrix based on the decoupling mode and the phase difference and tension difference between color groups, and calculates the compensation amount of non-target color groups based on the decoupling compensation matrix;

[0015] The control instruction module is used to map the compensation amount of each color group to the adjustment amount of working parameters and generate control instructions;

[0016] The execution module is used to execute the control instructions and drive the adjustment of the working parameters of each color group.

[0017] As a preferred solution of the multi-color printing synchronization control system with time-varying parameter self-tuning described in this application, wherein: the data acquisition module includes an encoder unit, a tension sensing unit, and a viscosity sensing unit;

[0018] The encoder unit includes encoders provided in each color group, which are used to acquire the phase of each color group; the phase is the phase of the printing shaft of the corresponding color group;

[0019] The tension sensing unit includes tension sensors provided in each color group, which are used to acquire the tension of each color group; the tension is the tension of the printing material of the corresponding color group;

[0020] The viscosity sensing unit includes viscosity sensors provided in each color group, which are used to acquire the ink viscosity of each color group.

[0021] As a preferred solution of the multi-color printing synchronization control system with time-varying parameter self-tuning described in this application, wherein: the decision-making module includes an abnormality identification unit; the abnormality identification unit is used to identify the target color group that needs compensation according to the state parameters of each color group; the abnormality identification unit identifies the target color group that needs compensation based on a preset abnormality identification strategy;

[0022] The abnormality identification strategy includes: continuously monitoring the tension of each color group; the abnormality identification unit is configured with a reference tension and a tension deviation threshold; if the absolute value of the difference between the tension of any color group and the reference tension continuously exceeds the tension deviation threshold within at least m milliseconds, the corresponding color group is the target color group;

[0023] The abnormal recognition strategy further includes: continuously monitoring the phase of each color group; the abnormal recognition unit is configured with a reference phase and a phase deviation threshold; if the absolute value of the difference between the phase of any color group and the reference phase is greater than the phase deviation threshold, the corresponding color group is the target color group;

[0024] The abnormal recognition strategy further includes: continuously monitoring the ink viscosity of each color group; the abnormal recognition unit is configured with a reference ink viscosity and an ink viscosity deviation threshold; if the absolute value of the difference between the ink viscosity of any color group and the reference ink viscosity is greater than the ink viscosity deviation threshold, the corresponding color group is the target color group.

[0025] As a preferred solution of the time-varying parameter self-tuning multi-color printing synchronization control system described in the present application, wherein: the decision-making module further includes a compensation mapping unit; the compensation mapping unit determines the compensation amount of the target color group based on the state parameters of the target color group;

[0026] The compensation amount of the target color group includes a speed compensation amount and a pressure compensation amount; the compensation mapping unit is configured with a compensation mapping model for determining the compensation amount of the target color group, specifically including:

[0027] Obtain the tension deviation value, phase deviation value, and ink viscosity deviation value of the target color group; input the tension deviation value, phase deviation value, and ink viscosity deviation into the compensation mapping model, and the compensation mapping model calculates and outputs the speed compensation amount and pressure compensation amount of the target color group;

[0028] The compensation mapping model is any one of a multi-layer perceptron, a support vector regression model, and a gradient boosting decision tree.

[0029] As a preferred solution of the time-varying parameter self-tuning multi-color printing synchronization control system described in the present application, wherein: the decision-making module further includes a decoupling decision-making unit; the decoupling decision-making unit is used to determine the decoupling mode between color groups according to the state parameters of each color group;

[0030] The decoupling mode between color groups includes strong decoupling, medium decoupling, and weak decoupling; the decoupling decision-making unit determines the decoupling mode between color groups based on fuzzy logic reasoning, specifically including:

[0031] Calculate the input variables of the fuzzy logic reasoning; the input variables include the mean value of the tension change rate, the average ink viscosity, and the material elastic modulus;

[0032] Fuzzify each input variable through a predefined membership function and the fuzzy set of the predefined input variables;

[0033] Perform fuzzy reasoning on the fuzzified input variables based on a predefined fuzzy rule base to generate a fuzzy output set;

[0034] The gravity method is used to defuzzify the fuzzy output set to obtain the crisp output value of the decoupling mode;

[0035] Based on the predefined output threshold range, the crisp output value of the decoupling mode is matched to strong decoupling, medium decoupling or weak decoupling.

[0036] As a preferred solution of the time-varying parameter self-tuning multi-color printing synchronization control system described in the present application, wherein: the compensation module includes a calculation unit and a decoupling compensation unit;

[0037] The calculation unit is used to calculate the phase difference and tension difference between any two color groups; the calculation unit is also used to calculate the threshold interval of the decoupling compensation amount of each non-target color group according to the decoupling mode;

[0038] The decoupling compensation unit dynamically generates a decoupling compensation matrix based on the phase difference and tension difference between any two color groups, and the threshold interval of the compensation amount of each non-target color group;

[0039] The decoupling compensation matrix is a matrix composed of decoupling compensation amounts; the element in the i-th row and j-th column of the decoupling compensation matrix represents the decoupling compensation amount of the j-th color group when the i-th color group is the target color group.

[0040] As a preferred solution of the time-varying parameter self-tuning multi-color printing synchronization control system described in the present application, wherein: the decoupling compensation unit dynamically generates a decoupling compensation matrix, specifically including:

[0041] Obtain the phase difference and tension difference between any two color groups;

[0042] Calculate the change rate of the tension difference between any two color groups;

[0043] Based on the phase difference, tension difference and change rate of the tension difference between color groups, calculate the decoupling compensation amount of any color group corresponding to each color group, and construct a decoupling compensation matrix;

[0044] Based on the threshold interval of the decoupling compensation amount, correct each decoupling compensation amount in the decoupling compensation matrix.

[0045] As a preferred solution of the time-varying parameter self-tuning multi-color printing synchronization control system described in this application, where: the decoupling compensation unit is further configured to calculate the compensation amount of the non-target color group according to the decoupling compensation matrix; the compensation amount of the non-target color group is the speed compensation amount; the calculation of the compensation amount of the non-target color group specifically includes: obtaining the decoupling compensation amount of any non-target color group corresponding to the current target color group based on the decoupling compensation matrix; the decoupling compensation unit is configured with a compensation correction strategy, and determining the compensation correction value of any non-target color group based on the compensation correction strategy; multiplying the decoupling compensation amount of any non-target color group corresponding to the current target color group by the compensation correction value of the non-target color group to obtain the compensation amount of the corresponding non-target color group.

[0046] As a preferred solution of the time-varying parameter self-tuning multi-color printing synchronization control system described in this application, where: the compensation correction strategy specifically includes: if any non-target color group is adjacent to the target color group, the compensation correction value of the corresponding non-target color group is 1, otherwise, calculating the distance between the center of the printing area of the non-target color group and the center of the printing area of the target color group as the associated distance of the non-target color group; the decoupling compensation unit is further configured with an associated distance threshold; if the associated distance of any non-target color group is greater than the associated distance threshold, the compensation correction value of the corresponding non-target color group is 0, otherwise, assigning a value to the compensation correction value of the non-target color group based on the associated distance, and the value range of the compensation correction value is (0, 1) and the compensation correction value is negatively correlated with the associated distance.

[0047] As a preferred solution of the time-varying parameter self-tuning multi-color printing synchronization control system described in this application, where: the control instruction module includes a control algorithm unit and an instruction generation unit;

[0048] The control algorithm unit is configured with a PID control algorithm for mapping the compensation amount of each color group to the adjustment amount of the working parameters; the adjustment amount of the working parameters includes the rotation speed adjustment amount of the servo motor and the valve opening adjustment amount of the pneumatic valve;

[0049] The control instruction module maps the compensation amount of each color group to the adjustment amount of the working parameters, specifically including: mapping the pressure compensation amount of any color group to the valve opening adjustment amount of the pneumatic valve of the corresponding color group based on the PID control algorithm; mapping the speed compensation amount of any color group to the rotation speed adjustment amount of the servo motor of the corresponding color group based on the PID control algorithm.

[0050] The instruction generation unit encodes and generates a control instruction based on the adjustment amount of the working parameters of each color group, and sends the control instruction to the execution module.

[0051] Compared with the prior art, the beneficial effects achieved by this application are as follows:

[0052] By collecting parameters such as tension, phase, and ink viscosity in real time, and combining with a compensation mapping model to dynamically adjust control parameters, the present application adapts to the differences in elastic modulus of different printing substrates; the changes in ink viscosity, etc. are monitored in real time and incorporated into the compensation strategy to avoid the reduction in accuracy caused by fixed parameters in traditional PID control. Incorporating phase, tension, and ink viscosity into a unified control framework realizes the collaborative optimization of multiple parameters and avoids the limitations of traditional single-variable regulation.

[0053] Based on fuzzy logic reasoning, according to variables such as the tension change rate, the average ink viscosity, and the material elastic modulus, the decoupling mode is automatically matched to accurately suppress the coupling effect. The compensation amount of the non-target color group is calculated through the phase difference, the tension difference, and their change rates to quantify the coupling strength between color groups; the spatial correlation is introduced, and different compensation strategies are adopted for adjacent color groups and non-adjacent color groups to improve the accuracy of decoupling. Brief Description of the Drawings

[0054] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings. Among them:

[0055] Figure 1 It is a schematic structural diagram of a multi-color printing synchronization control system with time-varying parameter self-tuning provided by the present application;

[0056] Figure 2 It is a schematic diagram of the working mode of a multi-color printing synchronization control system with time-varying parameter self-tuning provided by the present application. Detailed Embodiments

[0057] The following will describe the technical solutions of the present application in detail through the drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solutions of the present application, rather than limitations on the technical solutions of the present application. Without conflict, the technical features in the embodiments of the present application and the embodiments can be combined with each other.

[0058] This embodiment introduces a multi-color printing synchronization control system with time-varying parameter self-tuning. Referring to Figure 1 , the system includes a data acquisition module, a decision module, a compensation module, a control instruction module, and an execution module; among them:

[0059] The data acquisition module is used to collect the state parameters of each color group; the state parameters include phase, tension, and ink viscosity;

[0060] The multi-color printing system consists of multiple color groups, with each color group responsible for printing one color. Through precise registration and synchronization control, patterns of different colors are printed sequentially on the same substrate, ultimately forming a multi-color printed product.

[0061] The data acquisition module includes an encoder unit, a tension sensing unit, and a viscosity sensing unit;

[0062] The encoder unit includes encoders provided in each color group, which are used to collect the phase of each color group; the phase is the phase of the printing shaft of the corresponding color group;

[0063] The tension sensing unit includes tension sensors provided in each color group, which are used to collect the tension of each color group; the tension is the tension of the substrate of the corresponding color group;

[0064] The viscosity sensing unit includes viscosity sensors provided in each color group, which are used to collect the ink viscosity of each color group.

[0065] The decision-making module, based on the state parameters of each color group, identifies the target color group that needs compensation, determines the compensation amount of the target color group, and the decoupling mode between color groups;

[0066] The decision-making module includes an abnormality identification unit, a compensation mapping unit, and a decoupling decision unit;

[0067] The abnormality identification unit is used to identify the target color group that needs compensation according to the state parameters of each color group; the abnormality identification unit identifies the target color group that needs compensation based on a preset abnormality identification strategy;

[0068] The abnormality identification strategy includes: continuously monitoring the tension of each color group; the abnormality identification unit is configured with a reference tension and a tension deviation threshold; if the absolute value of the difference between the tension of any color group and the reference tension continuously exceeds the tension deviation threshold within at least m milliseconds, the corresponding color group is the target color group; m is a positive integer;

[0069] The abnormality identification strategy further includes: continuously monitoring the phase of each color group; the abnormality identification unit is configured with a reference phase and a phase deviation threshold; if the absolute value of the difference between the phase of any color group and the reference phase exceeds the phase deviation threshold, the corresponding color group is the target color group;

[0070] The abnormality identification strategy further includes: continuously monitoring the ink viscosity of each color group; the abnormality identification unit is configured with a reference ink viscosity and an ink viscosity deviation threshold; if the absolute value of the difference between the ink viscosity of any color group and the reference ink viscosity exceeds the ink viscosity deviation threshold, the corresponding color group is the target color group.

[0071] The compensation mapping unit determines the compensation amount of the target color group based on the state parameters of the target color group;

[0072] The compensation amount of the target color group includes a speed compensation amount and a pressure compensation amount; the compensation mapping unit is configured with a compensation mapping model for determining the compensation amount of the target color group, specifically including:

[0073] Obtain the tension deviation value, phase deviation value, and ink viscosity deviation value of the target color group; input the tension deviation value, phase deviation value, and ink viscosity deviation into the compensation mapping model, and the compensation mapping model calculates and outputs the speed compensation amount and pressure compensation amount of the target color group;

[0074] The compensation mapping model is any one of a multi-layer perceptron, a support vector regression model, and a gradient boosting decision tree.

[0075] The tension deviation value of the target color group is the difference between the tension of the target color group and the reference tension; the phase deviation value of the target color group is the difference between the phase of the target color group and the reference phase; the ink viscosity deviation value of the target color group is the difference between the ink viscosity of the target color group and the reference ink viscosity.

[0076] The decoupling decision unit is used to determine the decoupling mode between color groups according to the state parameters of each color group;

[0077] The decoupling mode between color groups includes strong decoupling, medium decoupling, and weak decoupling; the decoupling decision unit determines the decoupling mode between color groups based on fuzzy logic reasoning, specifically including:

[0078] Calculate the input variables of the fuzzy logic reasoning; the input variables include the mean value of the tension change rate, the average ink viscosity, and the material elastic modulus; among them, the mean value of the tension change rate is the average value of the tension change rates of all color groups; the average ink viscosity is the average value of the ink viscosities of all color groups; the material elastic modulus is the elastic modulus of the printing substrate (such as paper, plastic bags, etc.).

[0079] Fuzzify each input variable through a predefined membership function and the fuzzy set of the predefined input variables;

[0080] Perform fuzzy reasoning on the fuzzified input variables based on a predefined fuzzy rule base to generate a fuzzy output set;

[0081] The preferably fuzzified input variables in this embodiment are as follows: the mean value of the tension change rate is low or medium or high; the average ink viscosity is low or medium or high; the material elastic modulus is rigid or semi-rigid or elastic; further, one of the fuzzy rules in the preferably fuzzy rule base in this embodiment is as follows: if the material is elastic and the tension change rate is high, then the decoupling mode is strong decoupling.

[0082] The center of gravity method is used to defuzzify the fuzzy output set to obtain the crisp output value of the decoupling mode;

[0083] Based on the predefined output threshold range, the crisp output value of the decoupling mode is matched to strong decoupling, medium decoupling or weak decoupling.

[0084] The compensation module dynamically constructs a decoupling compensation matrix based on the decoupling mode and the phase difference and tension difference between color groups, and calculates the compensation amount of non-target color groups based on the decoupling compensation matrix;

[0085] The compensation module includes a calculation unit and a decoupling compensation unit;

[0086] The calculation unit is used to calculate the phase difference and tension difference between any two color groups;

[0087] The decoupling compensation unit dynamically generates a decoupling compensation matrix based on the phase difference and tension difference between any two color groups and the threshold interval of the compensation amount of each non-target color group; the decoupling compensation matrix is a matrix composed of decoupling compensation amounts; the element in the i-th row and j-th column of the decoupling compensation matrix represents the decoupling compensation amount of the j-th color group when the i-th color group is the target color group; both i and j are positive integers; when a certain color group needs to be adjusted due to parameter changes (such as sudden change in tension, change in ink viscosity), its adjustment action will be transmitted to adjacent color groups through the mechanical transmission chain or material tension, resulting in a coupling interference that affects the whole situation. The decoupling compensation amount is used to measure the strength of the coupling relationship between different color groups. The higher the decoupling compensation amount, the higher the compensation amount of the non-target color group when the corresponding target color group is compensated, so as to eliminate the influence of the target color group compensation on the non-target color group. The diagonal elements in the decoupling compensation matrix are the influence weights of the target color group on its own compensation amount, and always take the value of 1.

[0088] The calculation unit is also used to calculate the threshold interval of the decoupling compensation amount of each non-target color group according to the decoupling mode, specifically including: if the decoupling mode is strong decoupling, the threshold interval of the decoupling compensation amount is [-σ1, σ1]; σ1 is a preset first compensation threshold; if the decoupling mode is medium decoupling, the threshold interval of the decoupling compensation amount is [-σ2, σ2]; σ2 is a preset second compensation threshold; if the decoupling mode is weak decoupling, the threshold interval of the decoupling compensation amount is [-σ3, σ3]; σ3 is a preset third compensation threshold; σ1 is greater than σ2, and σ2 is greater than σ3.

[0089] The decoupling compensation unit dynamically generates a decoupling compensation matrix, specifically including:

[0090] Obtain the phase difference and tension difference between any two color groups;

[0091] Calculate the change rate of the tension difference between any two color groups;

[0092] Calculate the decoupling compensation amount corresponding to each color group of any color group based on the phase difference, tension difference, and the change rate of the tension difference between color groups, and construct a decoupling compensation matrix;

[0093] Based on the threshold interval of the decoupling compensation amount, correct each decoupling compensation amount in the decoupling compensation matrix.

[0094] Preferably, the formula for calculating the decoupling compensation amount based on the phase difference, tension difference, and the change rate of the tension difference between color groups in this embodiment is as follows:

[0095]

[0096] where c ij represents the decoupling compensation amount of the j-th color group when the i-th color group is the target color group; ΔT represents the tension difference between the i-th color group and the j-th color group; represents the change rate of ΔT; represents the phase difference between the i-th color group and the j-th color group; α is the tension difference coefficient, with a value of 0.05; β is the tension change rate coefficient, with a value of 0.02; γ is the phase difference coefficient, with a value of 0.1; in this formula, the tension difference, the change rate of the tension difference, and the phase difference are all dimensionless and participate in the calculation.

[0097] The decoupling compensation unit is further configured to calculate the compensation amount of non-target color groups according to the decoupling compensation matrix; the compensation amount of non-target color groups is the speed compensation amount; the calculation of the compensation amount of non-target color groups specifically includes: obtaining the decoupling compensation amount of any non-target color group corresponding to the current target color group based on the decoupling compensation matrix; the decoupling compensation unit is configured with a compensation correction strategy, and determines the compensation correction value of any non-target color group based on the compensation correction strategy; multiply the decoupling compensation amount of any non-target color group corresponding to the current target color group by the compensation correction value of the non-target color group to obtain the compensation amount of the corresponding non-target color group.

[0098] The compensation correction strategy specifically includes: if any non-target color group is adjacent to the target color group, the compensation correction value of the corresponding non-target color group is 1; otherwise, calculate the distance between the center of the printing area of the non-target color group and the center of the printing area of the target color group as the associated distance of the non-target color group; the decoupling compensation unit is further configured with an associated distance threshold; if the associated distance of any non-target color group is greater than the associated distance threshold, the compensation correction value of the corresponding non-target color group is 0; otherwise, assign a value to the compensation correction value of the non-target color group based on the associated distance, and the value range of the compensation correction value is (0, 1) and the compensation correction value is negatively correlated with the associated distance.

[0099] The control instruction module is configured to map the compensation amount of each color group to the adjustment amount of the working parameters and generate a control instruction;

[0100] The control instruction module includes a control algorithm unit and an instruction generation unit;

[0101] The control algorithm unit is configured with a PID control algorithm for mapping the compensation amount of each color group into the adjustment amount of the working parameters; the adjustment amount of the working parameters includes the rotation speed adjustment amount of the servo motor and the valve opening adjustment amount of the pneumatic valve;

[0102] The control instruction module maps the compensation amount of each color group into the adjustment amount of the working parameters, specifically including:

[0103] Based on the PID control algorithm, the pressure compensation amount of any color group is mapped into the valve opening adjustment amount of the pneumatic valve corresponding to the color group; based on the PID control algorithm, the speed compensation amount of any color group is mapped into the rotation speed adjustment amount of the servo motor corresponding to the color group.

[0104] The instruction generation unit encodes and generates a control instruction based on the adjustment amount of the working parameters of each color group, and sends the control instruction to the execution module.

[0105] The execution module is used to execute the control instruction and drive the adjustment of the working parameters of each color group.

[0106] The execution module includes an instruction parsing unit and an actuator unit;

[0107] The instruction parsing unit is used to receive the control instruction, parse the control instruction, and obtain the adjustment amount of the working parameters of each color group;

[0108] The actuator unit includes the servo motor and pneumatic valve of each color group; among them, the servo motor adjusts the speed of the corresponding color group based on the rotation speed adjustment amount; the speed of any color group is the rotation speed of the printing shaft of the color group; the pneumatic pressure valve adjusts the pressure of the corresponding color group based on the valve opening adjustment amount; the pressure of any color group is the printing pressure of the color group.

[0109] The working mode of the time-varying parameter self-tuning multi-color printing synchronization control system introduced in this embodiment is as Figure 2 shown. Referring to Figure 2 , the data acquisition module, decision module, compensation module, control instruction module, and execution module cooperate closely to achieve the automatic tuning of time-varying parameters and the synchronization control between printing color groups during the multi-color printing process, effectively reducing the printing deviation caused by parameter changes, thereby ensuring accurate colors and accurate overprinting of printed products.

[0110] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0111] The embodiments of the present application have been described above in conjunction with the accompanying drawings. However, the present application is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present application, those of ordinary skill in the art can also make many forms without departing from the purpose and the protected scope of the present application. These all fall within the protection scope of the present application.

Claims

1. A multi-color printing synchronization control system with time-varying parameter self-tuning, characterized in that: It includes a data acquisition module, a decision-making module, a compensation module, a control instruction module, and an execution module; among which: The data acquisition module is used to acquire the state parameters of each color group; the state parameters include phase, tension, and ink viscosity; Based on the state parameters of each color group, the decision-making module identifies the target color group that needs compensation, and determines the compensation amount of the target color group and the decoupling mode between color groups; The compensation module dynamically constructs a decoupling compensation matrix based on the decoupling mode and the phase difference and tension difference between color groups, and calculates the compensation amount of non-target color groups based on the decoupling compensation matrix; The control instruction module is used to map the compensation amount of each color group to the adjustment amount of working parameters and generate control instructions; The execution module is used to execute the control instructions and drive the adjustment of the working parameters of each color group.

2. The multi-color printing synchronization control system with time-varying parameter self-tuning according to claim 1, wherein: The data acquisition module includes an encoder unit, a tension sensing unit, and a viscosity sensing unit; The encoder unit includes encoders arranged in each color group, which are used to acquire the phase of each color group; the phase is the phase of the printing shaft of the corresponding color group; The tension sensing unit includes tension sensors arranged in each color group, which are used to acquire the tension of each color group; the tension is the tension of the printing material of the corresponding color group; The viscosity sensing unit includes viscosity sensors arranged in each color group, which are used to acquire the ink viscosity of each color group.

3. A multi-color printing synchronization control system with time-varying parameter self-tuning as described in claim 2, characterized in that: The decision-making module includes an abnormality identification unit; the abnormality identification unit is used to identify the target color group that needs compensation according to the state parameters of each color group; The abnormality identification unit identifies the target color group that needs compensation based on a preset abnormality identification strategy; The abnormality identification strategy includes: continuously monitoring the tension of each color group; the abnormality identification unit is configured with a reference tension and a tension deviation threshold; if the absolute value of the difference between the tension of any color group and the reference tension continuously exceeds the tension deviation threshold within at least m milliseconds, the corresponding color group is the target color group, and m is a positive integer; The abnormality identification strategy also includes: continuously monitoring the phase of each color group; the abnormality identification unit is configured with a reference phase and a phase deviation threshold; if the absolute value of the difference between the phase of any color group and the reference phase exceeds the phase deviation threshold, the corresponding color group is the target color group; The abnormality identification strategy also includes: continuously monitoring the ink viscosity of each color group; the abnormality identification unit is configured with a reference ink viscosity and an ink viscosity deviation threshold; if the absolute value of the difference between the ink viscosity of any color group and the reference ink viscosity exceeds the ink viscosity deviation threshold, the corresponding color group is the target color group.

4. The time-varying parameter self-tuning multi-color printing synchronization control system according to claim 3, wherein: The decision-making module also includes a compensation mapping unit; the compensation mapping unit determines the compensation amount of the target color group based on the state parameters of the target color group; The compensation amount of the target color group includes a speed compensation amount and a pressure compensation amount; The compensation mapping unit is configured with a compensation mapping model for determining the compensation amount of the target color group, specifically including: Obtain the tension deviation value, phase deviation value, and ink viscosity deviation value of the target color group; input the tension deviation value, phase deviation value, and ink viscosity deviation into the compensation mapping model, and the compensation mapping model calculates and outputs the speed compensation amount and pressure compensation amount of the target color group; The compensation mapping model is any one of a multi-layer perceptron, a support vector regression model, and a gradient boosting decision tree.

5. The multi-color printing synchronization control system with time-varying parameter self-tuning according to claim 4, characterized in that: The decision-making module further includes a decoupling decision-making unit; the decoupling decision-making unit is used to determine the decoupling mode between color groups according to the state parameters of each color group; The decoupling modes between color groups include strong decoupling, medium decoupling, and weak decoupling; The decoupling decision-making unit determines the decoupling mode between color groups based on fuzzy logic reasoning, specifically including: Calculating the input variables of fuzzy logic reasoning; the input variables include the average value of the tension change rate, the average ink viscosity, and the material elastic modulus; Fuzzifying each input variable through a predefined membership function and the fuzzy set of the predefined input variables; Performing fuzzy reasoning on the fuzzified input variables based on a predefined fuzzy rule base to generate a fuzzy output set; Performing defuzzification processing on the fuzzy output set by using the centroid method to obtain a clear output value of the decoupling mode; Based on a predefined output threshold range, matching the clear output value of the decoupling mode to strong decoupling, medium decoupling, or weak decoupling.

6. The time-varying parameter self-tuning multi-color printing synchronization control system according to claim 5, wherein: The compensation module includes a calculation unit and a decoupling compensation unit; The calculation unit is used to calculate the phase difference and tension difference between any two color groups; The calculation unit is further used to calculate the threshold interval of the decoupling compensation amount of each non-target color group according to the decoupling mode; The decoupling compensation unit dynamically generates a decoupling compensation matrix based on the phase difference and tension difference between any two color groups, and the threshold interval of the compensation amount of each non-target color group; The decoupling compensation matrix is a matrix composed of decoupling compensation amounts; the element in the i-th row and j-th column of the decoupling compensation matrix represents the decoupling compensation amount of the j-th color group when the i-th color group is the target color group, and both i and j are positive integers.

7. A time-varying parameter self-tuning multi-color printing synchronization control system according to claim 6, characterized in that: The decoupling compensation unit dynamically generates a decoupling compensation matrix, specifically including: Obtaining the phase difference and tension difference between any two color groups; Calculating the change rate of the tension difference between any two color groups; Based on the phase difference, tension difference, and change rate of the tension difference between color groups, calculating the decoupling compensation amount of any one color group corresponding to each color group, and constructing a decoupling compensation matrix; Based on the threshold interval of the decoupling compensation amount, correcting each decoupling compensation amount in the decoupling compensation matrix.

8. The multi-color printing synchronization control system with time-varying parameter self-tuning as claimed in claim 7, wherein: The decoupling compensation unit is further used to calculate the compensation amount of the non-target color group according to the decoupling compensation matrix; the compensation amount of the non-target color group is the speed compensation amount; calculating the compensation amount of the non-target color group specifically includes: obtaining the decoupling compensation amount of any non-target color group corresponding to the current target color group based on the decoupling compensation matrix; the decoupling compensation unit is configured with a compensation correction strategy, and determining the compensation correction value of any non-target color group based on the compensation correction strategy; multiplying the decoupling compensation amount of any non-target color group corresponding to the current target color group by the compensation correction value of the non-target color group to obtain the compensation amount of the corresponding non-target color group.

9. A time-varying parameter self-tuning multi-color printing synchronization control system according to claim 8, characterized in that: The compensation and correction strategy specifically includes: if any non-target color group is adjacent to the target color group, the compensation and correction value of the corresponding non-target color group is 1; otherwise, the distance between the center of the printing area of the non-target color group and the center of the printing area of the target color group is calculated as the associated distance of the non-target color group; the decoupling compensation unit is also configured with an associated distance threshold; if the associated distance of any non-target color group is greater than the associated distance threshold, the compensation and correction value of the corresponding non-target color group is 0; otherwise, the compensation and correction value of the non-target color group is assigned based on the associated distance, and the value range of the compensation and correction value is (0, 1) and the compensation and correction value is negatively correlated with the associated distance.

10. A multi-color printing synchronization control system with time-varying parameter self-tuning as described in claim 9, characterized in that: The control instruction module includes a control algorithm unit and an instruction generation unit; The control algorithm unit is configured with a PID control algorithm for mapping the compensation amount of each color group to the adjustment amount of the working parameters; the adjustment amount of the working parameters includes the rotation speed adjustment amount of the servo motor and the valve opening adjustment amount of the pneumatic valve; The control instruction module maps the compensation amount of each color group to the adjustment amount of the working parameters, specifically including: mapping the pressure compensation amount of any color group to the valve opening adjustment amount of the pneumatic valve of the corresponding color group based on the PID control algorithm; Mapping the speed compensation amount of any color group to the rotation speed adjustment amount of the servo motor of the corresponding color group based on the PID control algorithm; The instruction generation unit encodes and generates a control instruction based on the adjustment amount of the working parameters of each color group, and sends the control instruction to the execution module.

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