Control system and method for film deviation rectification of automatic cold fresh food packaging machine and storage medium

Abstract

The invention belongs to the technical field of film deviation rectification, and particularly relates to a control system and method for film deviation rectification of an automatic chilled food packaging machine and a storage medium, the control system comprises a multi-source sensing unit, and a position sensor, a speed sensor and a tension sensor are integrated in the multi-source sensing unit; a main controller and a coprocessor are integrated in the dual-core control unit; the composite execution unit comprises a deviation corrector, a speed controller and a tension controller; the multi-source sensing unit collects a film condition signal and feeds the film condition signal back to the dual-core control unit, and the dual-core control unit outputs a control signal to the composite execution unit to conduct film instant deviation correction. According to the control system and method for film deviation rectification of the automatic cold fresh food packaging machine, through cooperative linkage of the multi-source sensing unit, the dual-core control unit and the composite execution unit, dynamic and accurate deviation rectification in the film conveying process is achieved, and the technical defects that an existing control system is poor in adaptability, insufficient in control precision and weak in anti-interference capacity are effectively overcome.

Description

Technical Field

[0001] This invention belongs to the field of film correction technology, and particularly relates to a control system, method and storage medium for film correction in automatic packaging machines for chilled and fresh food. Background Technology

[0002] In the field of automated packaging for chilled and fresh foods, the stability of film transport in automated packaging machines directly determines the quality of the final packaged product and is one of the core technical aspects ensuring the continuity of the packaging production line and the product qualification rate. As a key material for the preservation and packaging of chilled and fresh foods, chilled and fresh film undergoes multiple continuous transport processes during the operation of automated packaging machines, including film feeding, forming, and sealing. During this process, the film is easily affected by a combination of factors, including its own material properties, fluctuations in the packaging machine's transport speed, and changes in tension, resulting in deviation phenomena such as static offset and periodic fluctuations.

[0003] The aforementioned deviation problem directly leads to irregular changes in film width. At best, it increases the cutting loss at the film edges and reduces the positioning accuracy of subsequent packaging processes such as forming and sealing, affecting the sealing performance and appearance regularity of the packaging. At worst, it causes the film to stretch and break, forcing the automatic packaging machine to stop. This not only significantly increases packaging energy consumption and material waste, but also causes unnecessary economic losses and production interruptions, thus hindering the improvement of efficiency and high-quality development of automatic packaging production lines for chilled and fresh foods.

[0004] To address the issue of film misalignment in automated packaging machines for chilled and fresh foods, various film misalignment control schemes have been developed in the existing technology. The core implementation logic of these schemes mostly adopts an architecture of "single sensor + single control algorithm": the film's transmission position inside the packaging machine is monitored in real time by a displacement sensor or edge detection sensor. When a misalignment signal is detected, the controller outputs a drive command based on a preset single control logic to regulate the misalignment execution mechanism (such as guide rollers or translation frames) to complete the position correction.

[0005] However, existing correction methods have significant technical flaws and are difficult to adapt to the complex operating conditions of automated packaging machines for chilled and fresh foods. On the one hand, existing technical solutions do not fully consider the coupling relationship between the dynamic changes in the conveying speed of the packaging machine, tension fluctuations, and film deviation. They only rely on the deviation displacement signal for feedback control, resulting in the control logic being disconnected from the actual packaging conditions and failing to fundamentally avoid the deviation risk caused by speed and tension disturbances. On the other hand, existing single control algorithms, such as proportional-integral-derivative (PID) control and fuzzy control, have inherent shortcomings. For example, PID control relies on parameter tuning to adapt to specific operating conditions. Dynamic fluctuations in film tension and speed during high-speed transmission can lead to mismatch of the original tuning parameters. If response speed is pursued, overshoot can easily occur, causing secondary film deviation. If control accuracy is emphasized, timeliness of response will be sacrificed, and deviation cannot be quickly suppressed. Although fuzzy control has a certain adaptability to nonlinear systems, the rule base design relies on experience. In high-speed scenarios, the rapid dynamic changes in film deviation can easily exceed the preset rule range, resulting in control lag or decreased accuracy, and it is difficult to cope with multi-factor coupled disturbances. Furthermore, the complex interference in high-speed packaging conditions amplifies the algorithm's shortcomings. The effects of interference factors such as film deformation, transmission mechanism vibration, and ambient temperature fluctuations are amplified under high-speed transmission. Moreover, the interference has random and instantaneous characteristics. A single algorithm lacks the ability to collaboratively sense and dynamically adjust multiple parameters. It relies solely on feedback control based on deviation displacement signals and cannot synchronously adapt to the dynamic changes in speed and tension. It is difficult to find a balance between rapid response and precise control, resulting in insufficient immunity margin to external interference. Consequently, it cannot effectively cope with external interference such as vibration and temperature fluctuations in the packaging production environment, leading to poor stability of the deviation correction effect.

[0006] With the continuous improvement of industrial automation and intelligence, the automatic packaging of chilled and fresh foods is developing towards high speed, high precision, and continuous operation. The market has placed more stringent requirements on the sealing performance, dimensional accuracy, and appearance quality of chilled and fresh food packaging. Traditional correction methods, due to their insufficient control precision, weak anti-interference ability, and narrow range of applicable working conditions, are no longer able to meet the needs of modern automatic packaging production of chilled and fresh foods, becoming a bottleneck restricting the technological upgrading of automatic packaging of chilled and fresh foods. Therefore, developing a film correction control method and system that can comprehensively consider multiple working condition parameters and has both high precision and strong anti-interference ability to solve the film deviation problem under the complex transmission conditions of automatic packaging machines for chilled and fresh foods has become a technical challenge that urgently needs to be overcome in the field of automatic packaging of chilled and fresh foods. Summary of the Invention

[0007] The present invention aims to address the shortcomings of the prior art by providing a control system, method and storage medium for film correction in automatic packaging machines for chilled and fresh food, so as to quickly output a precise film correction adjustment strategy while taking into account changes in parameters such as film tension and transmission speed.

[0008] In view of this, the present invention provides a control system for film correction in an automatic packaging machine for chilled food, comprising: A multi-source sensing unit that integrates a position sensor, a speed sensor, and a tension sensor; Dual-core control unit, which integrates a main controller and a coprocessor; The composite actuator includes a correction device, a speed controller, and a tension controller; The multi-source sensing unit is used to acquire thin-film condition signals and feed them back to the dual-core control unit. The dual-core control unit outputs control signals to the composite execution unit based on the thin-film condition signals. The composite execution unit performs real-time thin-film correction based on the control signals.

[0009] Furthermore, the position sensor, speed sensor, and tension sensor are deployed at one end of the outlet of the composite actuator.

[0010] Furthermore, the thin film condition signal fed back to the dual-core control unit by the multi-source sensing unit is a comprehensive characterization signal after preliminary fusion processing by the multi-source sensing unit. The comprehensive characterization signal is the degree of lateral offset of a target thin film located at the outlet position of the composite execution unit based on the current real-time transmission speed and real-time tension conditions. The degree of lateral offset of the thin film based on the current real-time transmission speed and real-time tension conditions is quantified by the percentage of the lateral offset of the thin film relative to the width of the thin film.

[0011] Furthermore, the main controller integrates adaptive MPC and PID algorithms, and can select either adaptive MPC fast correction mode or PID stability mode based on the relationship between the current lateral offset of the thin film and the set threshold. The coprocessor can rely on external thin film data as a reference to compare the current thin film state with the optimal thin film transmission state under the current operating conditions and output a feedforward compensation control strategy.

[0012] Furthermore, the adaptive MPC fast correction mode is as follows: the correction device is modeled and an adaptive adjustment mechanism is set. After receiving the thin film condition signal, the optimization problem in a finite number of steps in the future time domain is solved by rolling optimization, and the correction device execution signal of the first step is fed back to the correction device. In the next control cycle, the system parameter model is updated according to the actual degree of thin film correction, and prediction and optimization are performed again to form a closed-loop optimization.

[0013] Furthermore, the feedforward compensation control strategy refers to correcting the film tension and transmission speed through negative feedback when the film experiences fluctuations in tension and transmission speed, resulting in excessive film sag or film damage due to excessive tension.

[0014] Furthermore, the composite execution unit can realize two functions: feedforward compensation and lateral deviation correction. The feedforward compensation function is used to adjust the tension and transmission speed of the film, and the lateral deviation correction function is used to correct the lateral deviation of the film. The feedforward compensation function and the deviation correction function are executed independently.

[0015] A control method for film correction in an automatic packaging machine for chilled food, the method being used in the aforementioned control system, the control method for film correction in an automatic packaging machine for chilled food includes the following steps: S1, during the production process, the multi-source sensing unit continuously collects the thin film condition signal and feeds the thin film condition signal back to the dual-core control unit; S2, the dual-core control unit divides the thin-film condition signal and outputs corresponding control signals to the composite execution unit according to the division result; S3, the composite actuator performs real-time thin-film correction based on the control signal.

[0016] Furthermore, the thin film condition signal is the degree of lateral offset of the thin film based on the current real-time transmission speed and real-time tension conditions. In step S2, the system controls the system to either not start correction, enable PID stability mode, or enable adaptive MPC fast correction mode according to the magnitude of the lateral offset.

[0017] A computer-readable storage medium storing computer-executable instructions for causing a computer to perform the aforementioned control method for film correction in an automatic packaging machine for chilled food.

[0018] Compared with existing technologies, the control system, method, and storage medium for film correction in automatic packaging machines for chilled and fresh food described in this invention have the following advantages: The control system, method, and storage medium for film correction in an automatic packaging machine for chilled food described in this invention feeds back film condition signals to a dual-core control unit via a multi-source sensing unit. Based on the film condition signals, the dual-core control unit, according to their relationship with a set threshold, activates either adaptive MPC fast correction or PID stability mode, outputting correction device control signals and temperature and tension adjustment strategies. Based on the control signals and adjustment strategies, a composite execution unit achieves timely film correction and state adjustment, thereby achieving film correction under complex conditions with low energy consumption. It uses three types of sensors to obtain film offset at specific transmission speeds and tensions, and then feeds it back to the dual-core control unit, allowing it to comprehensively select a control strategy. The main controller and coprocessor separately manage the lateral correction and state compensation of the film, enabling low-energy and efficient output of the correction control strategy corresponding to the state. Finally, the use of feedforward compensation and correction device collaboration allows for the simultaneous adjustment of film tension, speed, and lateral correction to cope with complex situations encountered during film transmission. Ultimately, through the coordinated linkage of multi-source sensing units, dual-core control units, and composite execution units, dynamic and precise correction of the film transmission process in the automatic packaging machine for chilled food is achieved, effectively solving the technical defects of existing control systems such as poor adaptability, insufficient control precision, and weak anti-interference capability. Attached Figure Description

[0019] Figure 1 This is a structural diagram of the control system for film correction in an automatic packaging machine for chilled and fresh food as described in this invention. Figure 2 This is a simplified schematic diagram of the arrangement of the multi-source sensing unit in this invention; Figure 3 This is a flowchart illustrating the control method for film correction in an automatic packaging machine for chilled and fresh food as described in this invention. Figure 4 This is a flowchart of the main controller described in this invention; The markings in the diagram are as follows: 1. Position sensor; 2. Speed ​​sensor; 3. Tension sensor; 4. Main controller; 5. Coprocessor; 6. Corrector; 7. Speed ​​controller; 8. Tension controller. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0021] It should be noted that all directional and positional terms used in this invention, such as "up," "down," "left," "right," "front," "back," "vertical," "horizontal," "inner," "outer," "top," "lower," "lateral," "longitudinal," and "center," are only used to explain the relative positional relationships and connections between components in a specific state (as shown in the accompanying drawings). They are merely for the convenience of describing the invention and do not require the invention to be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on the invention. Furthermore, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated.

[0022] In the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0023] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0024] like Figures 1-4 As shown, the present invention provides a control system for film correction in an automatic packaging machine for chilled food, comprising: A multi-source sensing unit, which integrates a position sensor 1, a speed sensor 2 and a tension sensor 3; Dual-core control unit, which integrates main controller 4 and coprocessor 5; The composite actuator includes a correction device 6, a speed controller 7, and a tension controller 8; The multi-source sensing unit is used to acquire thin-film condition signals and feed them back to the dual-core control unit. The dual-core control unit outputs control signals to the composite execution unit based on the thin-film condition signals. The composite execution unit performs real-time thin-film correction based on the control signals.

[0025] As some examples of the present invention, the number of position sensor 1, speed sensor 2 and tension sensor 3 is not limited, and there may be one or more.

[0026] This invention overcomes the limitation of traditional single sensors that can only acquire film displacement signals by deploying multi-source sensing units at specific workstations in an automatic packaging machine for chilled food. It continuously and synchronously collects key condition signals during the film transmission process and feeds the collected film condition signals back to the dual-core control unit. By integrating multi-dimensional signals, it achieves comprehensive perception of the film transmission status and provides reliable data support for subsequent precise control.

[0027] Furthermore, the position sensor 1, speed sensor 2, and tension sensor 3 are all deployed at one end of the outlet of the composite actuator.

[0028] The advantage of this deployment method lies in its ability to capture the state of the film after correction in real time, forming a closed-loop feedback chain of "correction-detection." This avoids signal delays caused by excessive distance between the sensor and the composite actuator, ensuring the immediacy and accuracy of the correction effect. Specifically, position sensor 1 is used for the core detection of the film's lateral offset position, velocity sensor 2 is used to acquire the film's current transmission rate in real time, and tension sensor 3 is used to accurately monitor tension changes during film transmission. The signals acquired by these three sensors are transmitted synchronously and mutually verified, jointly constructing a complete data profile of the film's transmission state.

[0029] As a preferred example of the present invention, the multi-source sensing unit has a built-in signal preprocessing module. This module is used to filter, reduce noise, amplify and convert the raw signals collected by the three types of sensors mentioned above, remove invalid signals caused by vibration, electromagnetic interference and other factors in the production environment, and fuse the processed signals into a unified thin-film condition signal.

[0030] It should be noted that the thin film condition signal fed back to the dual-core control unit in this invention is not the original acquisition signal of a single sensor, but a comprehensive characterization signal after preliminary fusion processing by multiple source sensing units. Specifically, it is defined as: the degree of lateral offset of a target thin film located at the outlet position of the composite actuator, based on the current real-time transmission speed and real-time tension conditions.

[0031] To quantify the degree of lateral offset more accurately and intuitively, this invention uses the percentage of the film's lateral offset relative to the film width as the core metric—the degree of lateral offset. The calculation formula is: Degree of lateral offset = (film lateral offset / film width) × 100%.

[0032] The advantage of using this percentage to quantify lateral offset is that it can be adapted to cold-chain packaging films of different widths, avoiding inconsistencies in the judgment standards for lateral offset due to differences in film width, and improving the universality and adaptability of the control method. For example, when the film width is 500mm and the lateral offset is 5mm, the percentage of lateral offset is 1%; when the film width is 300mm and the lateral offset is also 5mm, the percentage of lateral offset is approximately 1.67%. The percentage clearly distinguishes the offset risk level of films of different widths.

[0033] Furthermore, regarding the specific selection and setting of the sensor, this invention provides preferred embodiments but does not limit them to a single one: the position sensor 1 is preferably a grating sensor. Grating sensors have the characteristics of high detection accuracy and strong anti-interference ability, and can accurately capture the slight displacement of the film edge, which is suitable for the needs of high-speed transmission scenarios in automatic packaging machines for chilled and fresh food.

[0034] In other alternative embodiments, the position sensor 1 can also be a laser sensor or a photoelectric sensor. The laser sensor is suitable for detecting transparent or semi-transparent cold-cooking films, while the photoelectric sensor has the advantages of lower cost and convenient installation. It can be flexibly selected according to the cost budget and film characteristics of the actual production scenario.

[0035] Regarding the number of sensors, the position sensor 1 can be deployed individually to detect the offset of one side edge of the film at a single point; or it can be deployed in pairs symmetrically to detect the offset of both sides of the film simultaneously. The difference between the offsets on both sides can further improve the accuracy of the offset judgment. This deployment method is particularly suitable for scenarios where the film is prone to irregular twisting and offset.

[0036] Furthermore, the selection and setting of the speed sensor 2 and tension sensor 3 are similar to those of the position sensor 1. For example, the speed sensor 2 can be an incremental encoder, Hall sensor, etc., and the tension sensor 3 can be a pressure tension sensor, tension transmitter, etc. The specific configuration can be flexibly adapted according to the type of transmission mechanism of the packaging machine and the characteristics of the film material, such as thickness and flexibility. They can be deployed independently or combined according to the detection accuracy requirements. No specific limitations are made here.

[0037] Furthermore, the dual-core control unit comprises a main controller 4 and a coprocessor 5. The main controller 4 integrates an adaptive MPC algorithm and a PID algorithm, and can select either an adaptive MPC fast correction mode or a PID stability mode based on the current film deviation, i.e., the relationship between the lateral offset and the set threshold. The coprocessor 5, on the other hand, relies on external film data as a reference to compare the current film state with the optimal film transmission state under the current operating conditions and outputs a feedforward compensation control strategy.

[0038] The MPC algorithm is a control algorithm that relies on a dynamic model of the system to predict the system's behavior over a future period. Its mathematical form is as follows: in, For state, To control the input.

[0039] Specifically, in this invention, Let be the system state vector at time k. Let k be the control input vector at time k. In the thin-film correction scenario described in this invention... It may include: current film lateral offset, transmission speed, tension value, and other state quantities; These are correction commands output by the dual-core control unit, such as the guide roller angle adjustment amount and tension adjustment amount.

[0040] In addition, y(k) represents the system output vector at time k. In the thin-film correction scenario, y(k) is the feedback signal collected by the multi-source sensing unit, such as the actual offset and actual velocity. A represents the state transition matrix, which has an dimension of n*m. It describes how the state x(k) at time k evolves to the state x(k+1) at time k+1, reflecting the dynamic characteristics of the thin film system itself. B represents the input matrix, which has a dimension of n*p, where p is the dimension of the control input, used to describe the degree of influence of the control input u(k) on the state change, such as the adjustment efficiency of the offset by the correction command. C represents the output matrix, which has a dimension of q*n, where q is the dimension of the output. It is used to describe how the system state x(k) is mapped to the output y(k), reflecting the correspondence between the state variables and the sensor feedback signals.

[0041] As examples of the present invention, within each control cycle, based on the current system state and model, a finite-step optimal control problem in the time domain is solved while satisfying the system dynamics equations and constraints, minimizing the objective function as follows: ; Where Q is the weight matrix of the output error, used to measure the predicted output. Compared with reference trajectory The difference lies in the input; a larger Q value will make the system focus more on reducing output error. R is a weight matrix that controls the input variation and is used to measure the input... With a larger R value, the system will focus more on reducing changes in control input, thereby reducing system energy consumption or avoiding excessive control actions.

[0042] The MPC algorithm described above is existing technology, therefore its specific execution process will not be described in detail in this invention.

[0043] As a preferred example of the present invention, after each optimization, only the first step control input is applied to the system. In the next control cycle, the state is updated according to the actual measurement value, and prediction and optimization are performed again to form closed-loop control.

[0044] Specifically, when the main controller 4 of the dual-core control unit starts the adaptive MPC algorithm, it predicts the film offset trend over a future period, such as the next 5 control cycles, based on the film state collected by the multi-source sensing unit, such as offset, speed, and tension. It then calculates the optimal control input for these 5 cycles, such as the guide roller adjustment angle and speed. However, at this time, only the control input command for the first cycle is sent to the composite execution unit, such as driving the correction device 6 to adjust the guide roller by 1°, instead of executing the commands for the subsequent 4 cycles at once. After entering the next control cycle, the multi-source sensing unit collects the actual film state after executing the first control step (e.g., whether the actual offset has decreased, whether the speed / tension is stable). This "actual measurement value" replaces the predicted value of the previous cycle, updating the current system state. The algorithm then re-predicts (based on the updated actual state to predict the offset trend for the next 5 cycles) and optimizes (recalculates the optimal control input for the next 5 cycles), and only executes the first control input of the newly optimized result. Repeat the process of "optimization → execution of only step one → actual test update → re-optimization" to form a closed-loop control of the adaptive MPC algorithm.

[0045] The film transport process in automated packaging machines for chilled food is subject to random disturbances such as speed fluctuations and tension changes. Predicting all control commands at once can easily lead to deviations due to these disturbances. The adaptive MPC algorithm described in this invention introduces an adaptive mechanism compared to traditional MPC, allowing it to dynamically adjust model parameters based on new measurement data, thus better adapting to changes in system characteristics. This rolling optimization method can correct predictions in real time using actual measurements, avoiding accumulated errors and ensuring that the correction control always closely matches the current real-world conditions, improving correction accuracy and anti-interference capabilities in high-speed transport scenarios.

[0046] Similarly, the adaptive MPC fast correction mode described in this invention refers to: modeling the correction device 6 and setting an adaptive adjustment mechanism; after receiving the thin film condition signal, rolling optimization is performed to solve the optimization problem in a finite number of steps in the future time domain, and the execution signal of the correction device 6 in the first step is fed back to the correction device 6; in the next control cycle, the system parameter model is updated according to the actual degree of thin film correction, and prediction and optimization are performed again to form a closed-loop optimization.

[0047] Ideally, the membrane should perfectly follow the corrector 6 to its corresponding position. However, in reality, during the stable correction phase, a dynamic balance is achieved between the frictional force and the tangential component of the tension on the membrane. The lateral deflection distance of the membrane is proportional to the distance the corrector 6 moves, and this proportionality coefficient varies under different operating conditions. In this case, the traction coefficient can be used... The proportional relationship of the thin-film follower polarizer 6 in lateral movement is used to characterize the polarization process. Different traction coefficients naturally have different effects on the polarization correction process. To compensate for this loss and achieve the fastest and most accurate polarization correction, this invention sets the final adaptive MPC fast polarization correction signal as the algorithm output. .

[0048] As examples of the present invention, Table 1 below provides examples of the traction coefficients of the film under different tensions and transport speeds: Table 1. Traction coefficients of the film under different tensions and transport speeds Furthermore, it should be noted that the PID algorithm is a classic feedback control algorithm widely used in various industrial and automation control systems. It adjusts the controller output to make the actual output value of the system as close as possible to the desired target value. The specific formula is as follows: ; in, Is the controller in time The output; It is the proportional gain, and the error. Proportional; It is the integral gain, and the error. The integral is proportional to the value and is used to eliminate steady-state errors; It is the differential gain, and the error It is proportional to the derivative, and is used to predict the future trend of errors and improve the system's response speed; It is in time The error is the difference between the set value and the actual output value. It is the integral of the error, from 0 to The cumulative error; It is the derivative of the error, that is, the rate of change of the error.

[0049] Furthermore, the PID stability mode described in this invention refers to: modeling the corrector 6 and setting appropriate proportional, integral and derivative gains, and after receiving the thin film condition signal, calculating the control signal accordingly to adjust the action of the corrector 6.

[0050] It should be noted that the feedforward compensation control strategy described in this invention refers to the positive feedback of film tension and transmission speed when the film experiences fluctuations in tension and transmission speed, resulting in excessive film sag or film damage due to excessive tension.

[0051] Furthermore, the composite actuator can realize two functions: feedforward compensation and lateral correction. The feedforward compensation function can adjust the tension and transmission speed of the film; the lateral correction function can correct the lateral deviation of the film.

[0052] As a preferred example of the present invention, the feedforward compensation function and the lateral correction function are executed independently, that is: If the film has no lateral deviation and only changes in tension and velocity, the system will only perform feedforward compensation. If the film has no change in speed or tension and only deviates laterally, the system will only perform lateral correction. The composite execution unit operates collaboratively when the film experiences the following conditions: film deviation occurs during feedforward compensation, speed and tension changes occur during correction, or both occur simultaneously, and feedforward compensation is executed before lateral correction. That is, this method first adjusts the tension and transmission speed of the film, and in the process of adjusting the film speed and tension to the optimal transmission state, lateral correction is performed in real time based on the actual state of the film at that moment.

[0053] As a preferred example of the present invention, the lateral correction function can be achieved by a servo motor controlling the rotation of the correction roller, or by a machine driving a ball screw; the feedforward compensation function can be achieved by a torque motor controlling the tension roller to adjust the film tension, a speed regulating motor controlling the transmission roller to adjust the film transmission speed, or by other means.

[0054] Specifically, the active guiding mechanism in the composite execution unit can directly correct the lateral offset of the film by driving the guide rollers with a servo motor to make angle fine adjustments or lateral translation based on the correction direction and amplitude in the control signal. The auxiliary tension adjustment mechanism responds synchronously to the tension adaptation command in the control signal, and keeps the tension of the film stable during the correction process by finely adjusting the pressure of the tension roller, avoiding sudden tension changes caused by the correction operation, and thus preventing wrinkles or stretching damage to the film. At the same time, since the multi-source sensing unit is deployed at the outlet of the composite execution unit, it can feed back the corrected film status to the dual-core control unit in real time, forming a closed-loop control link of "acquisition-control-execution-reacquisition", ensuring the continuity and stability of the correction effect and realizing dynamic and precise correction during the film transmission process.

[0055] As some examples of the present invention, the multi-source sensing unit, dual-core control unit and composite execution unit are interconnected via industrial buses, such as CAN bus and EtherCAT bus, to achieve high-speed data interaction, ensure the real-time performance and reliability of signal transmission, and adapt to the high-speed continuous production requirements of automatic packaging machines for chilled and fresh food.

[0056] Furthermore, the present invention also provides a control method for film correction in an automatic packaging machine for chilled food. The method is used in the aforementioned control system, and includes the following steps: S1, during the production process, the multi-source sensing unit continuously collects the thin film condition signal and feeds the thin film condition signal back to the dual-core control unit; S2, the dual-core control unit divides the thin-film condition signal and outputs corresponding control signals to the composite execution unit according to the division result; S3, the composite actuator performs real-time thin-film correction based on the control signal.

[0057] As a preferred example of the present invention, in step S2, the thin film condition signal is a comprehensive characterization signal after preliminary fusion processing by the multi-source sensing unit. The comprehensive characterization signal is the degree of lateral offset of a target thin film located at the outlet position of the composite actuator based on the current real-time transmission speed and real-time tension conditions. The degree of lateral offset of the thin film based on the current real-time transmission speed and real-time tension conditions is quantified by the percentage of the lateral offset of the thin film relative to the width of the thin film.

[0058] As a preferred example of the present invention, in step S2, the degree of lateral offset of the thin film is compared with a set threshold, and the thin film condition signal is divided into different levels according to the relative magnitude of the degree of lateral offset and the set threshold.

[0059] As some specific examples of the present invention, the set threshold includes a level Below, second tier and three gears The above describes the different settings. In setting one, the film is considered to have no offset, and the correction mechanism is not activated. In setting two, the film has a slight offset, and subsequent processing steps allow the correction device 6 to complete the correction within a relatively long time without affecting the processing quality; in this case, the PID stability mode is activated to reduce energy consumption. In setting three, the film has a severe offset, which will directly affect subsequent processing steps; therefore, the adaptive MPC fast correction mode is activated to achieve timely correction of the film position.

[0060] In step S2, after receiving the thin-film condition signal from the multi-source sensing unit, the dual-core control unit performs in-depth analysis and calculation on the signal through preset dual-core collaborative control logic, generating a precise control signal and outputting it to the composite execution unit. This step adopts a dual-core control architecture, overcoming the shortcomings of traditional single control units, such as low computational efficiency and rigid control logic. On the one hand, through signal fusion and offset risk assessment, a multi-dimensional working condition model is constructed based on the percentage of lateral offset, real-time speed, and real-time tension to determine whether the current offset state of the thin film needs correction, the urgency of correction, and the correction magnitude. On the other hand, control strategy optimization and command generation dynamically match the optimal correction algorithm based on the offset risk assessment results, ensuring that the control signal can accurately adapt to the current thin-film transmission conditions and avoid overshoot or lag problems.

[0061] In step S3, after receiving the control signal output by the dual-core control unit, the composite execution unit performs real-time and precise web-correction operations on the film through an integrated multi-mechanism collaborative linkage mechanism. This step adopts a composite execution architecture, which differs from the traditional web-correction method using a single guide roller. The composite execution unit integrates both feedforward compensation and lateral web-correction functions, enabling it to simultaneously adapt to the film's transmission speed and tension state during the web-correction process, avoiding film stretching and breakage problems caused by simply adjusting the offset.

[0062] In addition, the present invention provides a computer-readable storage medium storing computer-executable instructions for causing a computer to execute the above-described control method for film correction in an automatic packaging machine for chilled food.

[0063] In summary, the control system, method, and storage medium for film correction in an automatic packaging machine for chilled food described in this invention feeds back film condition signals to a dual-core control unit via a multi-source sensing unit. Based on the film condition signals, the dual-core control unit, according to their relationship with a set threshold, enables adaptive MPC fast correction or PID stability mode, outputting correction device control signals and temperature tension adjustment strategies. Based on the control signals and adjustment strategies, a composite execution unit achieves timely film correction and state adjustment, thereby achieving film correction under complex conditions with low energy consumption. It uses three sensors to obtain film offset at specific transmission speeds and tensions, and then feeds it back to the dual-core control unit, allowing it to comprehensively select a control strategy. The main controller 4 and coprocessor 5 separately manage the lateral correction and state compensation of the film, enabling low-energy and efficient output of the correction control strategy corresponding to the state. Finally, the collaborative operation of feedforward compensation and correction device 6 can simultaneously address film tension adjustment, speed adjustment, and lateral correction to cope with complex situations encountered during film transmission. Ultimately, through the coordinated linkage of multi-source sensing units, dual-core control units, and composite execution units, dynamic and precise correction of the film transmission process in the automatic packaging machine for chilled food is achieved, effectively solving the technical defects of existing control systems such as poor adaptability, insufficient control precision, and weak anti-interference capability.

[0064] The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A control system for film correction in an automatic packaging machine for chilled food, characterized in that, include: A multi-source sensing unit that integrates a position sensor (1), a speed sensor (2), and a tension sensor (3). A dual-core control unit, which integrates a main controller (4) and a coprocessor (5). The composite actuator includes a correction device (6), a speed controller (7), and a tension controller (8). The multi-source sensing unit is used to acquire thin-film condition signals and feed them back to the dual-core control unit. The dual-core control unit outputs control signals to the composite execution unit based on the thin-film condition signals. The composite execution unit performs real-time thin-film correction based on the control signals.

2. The control system for film correction in an automatic packaging machine for chilled food according to claim 1, characterized in that, The position sensor (1), speed sensor (2) and tension sensor (3) are deployed at one end of the outlet of the composite actuator.

3. The control system for film correction in an automatic packaging machine for chilled food according to claim 1, characterized in that, The thin film condition signal fed back to the dual-core control unit by the multi-source sensing unit is a comprehensive characterization signal after preliminary fusion processing by the multi-source sensing unit. The comprehensive characterization signal is the degree of lateral displacement of a target thin film located at the outlet position of the composite actuator based on the current real-time transmission speed and real-time tension conditions. The degree of lateral displacement of the thin film based on the current real-time transmission speed and real-time tension conditions is quantified by the percentage of the lateral displacement of the thin film relative to the width of the thin film.

4. The control system for film correction in an automatic packaging machine for chilled food according to claim 1, characterized in that, The main controller (4) integrates adaptive MPC algorithm and PID algorithm, and can select adaptive MPC fast correction mode or PID stability mode according to the relationship between the current lateral offset of the thin film and the set threshold. The coprocessor (5) can rely on external thin film data as a reference to compare the current thin film state with the optimal thin film transmission state under the current working condition and output a feedforward compensation control strategy.

5. The control system for film correction in an automatic packaging machine for chilled food according to claim 4, characterized in that, The adaptive MPC fast correction mode is as follows: the correction device (6) is modeled and an adaptive adjustment mechanism is set. After receiving the thin film condition signal, the optimization problem of a finite number of steps in the future time domain is solved by rolling optimization, and the execution signal of the correction device (6) in the first step is fed back to the correction device (6). In the next control cycle, the system parameter model is updated according to the actual degree of thin film correction, and prediction and optimization are performed again to form a closed loop optimization.

6. The control system for film correction in an automatic packaging machine for chilled food according to claim 4, characterized in that, The feedforward compensation control strategy refers to correcting the film tension and transmission speed through negative feedback when the film experiences fluctuations in tension and transmission speed, resulting in excessive film sag or film damage due to excessive tension.

7. The control system for film correction in an automatic packaging machine for chilled food according to claim 4, characterized in that, The composite actuator can perform two functions: feedforward compensation and lateral deviation correction. The feedforward compensation function is used to adjust the tension and transmission speed of the film, while the lateral deviation correction function is used to correct the lateral deviation of the film. The feedforward compensation function and the deviation correction function are executed independently.

8. A control method for film correction in an automatic packaging machine for chilled food, the method being used in the control system described in any one of claims 1 to 7, the control method for film correction in an automatic packaging machine for chilled food comprising the steps of: S1, during the production process, the multi-source sensing unit continuously collects the thin film condition signal and feeds the thin film condition signal back to the dual-core control unit; S2, the dual-core control unit divides the thin-film condition signal and outputs corresponding control signals to the composite execution unit according to the division result; S3, the composite actuator performs real-time thin-film correction based on the control signal.

9. The control method for film correction in an automatic packaging machine for chilled food according to claim 8, characterized in that, The thin film condition signal is the degree of lateral offset of the thin film based on the current real-time transmission speed and real-time tension conditions. In step S2, the system controls the system to either not start correction, enable PID stability mode, or enable adaptive MPC fast correction mode according to the magnitude of the lateral offset.

10. A computer-readable storage medium storing computer-executable instructions for causing a computer to perform the control method for film correction in an automatic packaging machine for chilled food as described in any one of claims 8 to 9.

Images