Glue spraying control system and device for carton packaging machine

Abstract

The invention discloses a carton packaging machine glue spraying control system and device, and belongs to the technical field of automatic control, and the carton packaging machine glue spraying control system comprises a speed monitoring module, an image acquisition module, a feedforward control module, a feedback control module, a fusion processing module and a glue spraying control module. According to the method, a control strategy combining feedforward and feedback is adopted, dynamic weighted fusion is carried out on feedforward and feedback compensation according to the dynamic condition of the system, quick response and accurate correction can be taken into account, and the dynamic performance and the steady-state precision of glue spraying control are improved.

Description

Technical Field

[0001] This invention relates to the field of automation control technology, and in particular to a glue spraying control system and device for a carton packaging machine. Background Technology

[0002] Carton packaging machines are widely used automated equipment in industries such as tobacco and pharmaceuticals. One of their core processes is applying adhesive lines to designated locations on the carton using a glue spraying system to complete the sealing process. The quality of the glue spraying directly affects the appearance integrity and sealing performance of the packaging. In high-speed, continuous automated production processes, precise and stable control of the glue spraying process is a key link in ensuring product quality and production efficiency, and is a typical industrial process control problem.

[0003] Currently, most existing glue spraying control methods for carton packaging machines are relatively simple. Some systems use open-loop control, triggering the glue spraying action based on preset fixed parameters or fixed positions counted by encoders. This method does not consider real-time changes in the equipment's operating speed. Other systems introduce basic feedback control, such as using photoelectric sensors to detect the presence of glue lines, but their main function is to reject finished products or issue fault alarms, lacking the ability to adjust the glue spraying process in real time. While some advanced systems employ closed-loop control, they typically only adjust a single variable, such as the glue spraying position.

[0004] However, open-loop control systems are prone to problems such as glue line misalignment and uneven length when faced with equipment start-up, shutdown, or speed fluctuations, as they cannot adapt to changes in conveyor speed. Feedback systems with only simple presence or absence detection cannot monitor and adjust more refined quality indicators such as glue line width and continuity. Even systems using single-variable closed-loop control exhibit lag in response to rapid disturbances such as sudden speed changes, making it difficult to effectively suppress dynamic errors. Furthermore, their ability to adjust for quality drift caused by slow variables such as glue viscosity changes and nozzle wear is relatively limited, failing to achieve comprehensive quality assurance. Summary of the Invention

[0005] To address the aforementioned issues, this invention provides a glue spraying control system and device for a carton packaging machine. It employs a control strategy that combines feedforward and feedback, and dynamically weights and fuses the feedforward and feedback compensations based on the system's dynamic conditions. This approach balances rapid response with precise correction, thereby improving the dynamic performance and steady-state accuracy of the glue spraying control.

[0006] The above objectives can be achieved through the following approach: A glue spraying control system for a carton packaging machine includes a speed monitoring module for acquiring the real-time conveying speed of the carton to be glued, analyzing the real-time conveying speed, and generating speed change state parameters; an image acquisition module for acquiring glue line images on the carton to be glued and the preceding carton, generating real-time glue line image data; a feedforward control module for calculating feedforward compensation parameters based on the speed change state parameters; a feedback control module for performing quality feature analysis on the real-time glue line image data to obtain actual glue line feature vectors, comparing the actual glue line feature vectors with a preset target glue line quality template, and generating feedback compensation parameters; a fusion processing module for assigning dynamic weights to the feedforward compensation parameters and the feedback compensation parameters based on the speed change state parameters, and fusing the feedforward compensation parameters and the feedback compensation parameters based on the dynamic weights to generate comprehensive dynamic compensation parameters; and a glue spraying control module for generating baseline glue spraying parameters based on the real-time conveying speed, adjusting the baseline glue spraying parameters using the comprehensive dynamic compensation parameters, and generating a final glue spraying control command.

[0007] Optionally, the speed monitoring module includes: a conveying monitoring unit for acquiring the real-time conveying speed of the current adhesive strip box; a rate of change monitoring unit for performing differential calculation on the real-time conveying speed to acquire the rate of change of speed; and a control start unit for starting the control system when the absolute value of the rate of change of speed exceeds a preset stability threshold, and using the rate of change of speed as a speed change state parameter.

[0008] Optionally, the feedforward control module includes: a feedforward relationship storage unit for establishing a feedforward mapping relationship library describing the correspondence between speed changes and compensation amounts; a compensation retrieval unit for inputting the speed change state parameters into the feedforward mapping relationship library and retrieving compensation coefficients; and a feedforward parameter calculation unit for performing calculations using the compensation coefficients and the real-time conveying speed to generate feedforward compensation parameters.

[0009] Optionally, the feedback control module includes: a glue spraying feature extraction unit, used to extract glue line width, glue line continuity, and glue line centerline offset from the real-time glue line image data to form an actual glue line feature vector; a deviation calculation unit, used to perform vector subtraction operation between the actual glue line feature vector and the target feature vector in the preset target glue line quality template to obtain a feature deviation vector; and a feedback parameter calculation unit, used to calculate and generate feedback compensation parameters based on the feature deviation vector.

[0010] Optionally, the step of calculating and generating feedback compensation parameters based on the feature deviation vector includes: performing proportional-integral-differential operations on the feature deviation vector to generate a preliminary compensation value; performing amplitude limiting processing on the preliminary compensation value to ensure that it is within the safe operating range of the actuator; and outputting the amplitude-limited value as the feedback compensation parameter.

[0011] Optionally, the fusion processing module includes: a weight calculation unit, configured to assign dynamic weights to the feedforward compensation parameter and the feedback compensation parameter based on the velocity change state parameter and the feature deviation vector, wherein the dynamic weights include a first weight of the feedforward compensation parameter and a second weight of the feedback compensation parameter; a weighted calculation unit, configured to multiply the feedforward compensation parameter by the first weight to obtain a weighted feedforward parameter; multiply the feedback compensation parameter by the second weight to obtain a weighted feedback parameter; and perform a summation operation on the weighted feedforward parameter and the weighted feedback parameter to generate a comprehensive dynamic compensation parameter.

[0012] Optionally, assigning dynamic weights to the feedforward compensation parameter and the feedback compensation parameter based on the speed change state parameter and the feature deviation vector includes: assigning a first weight to the feedforward compensation parameter based on the magnitude of the speed change rate in the speed change state parameter, wherein the first weight is positively correlated with the magnitude of the speed change rate; tracking the changes of the feature deviation vector in multiple adjacent production cycles and calculating the deviation convergence speed of the generated feature deviation vector; and assigning a second weight to the feedback compensation parameter based on the deviation convergence speed, wherein the second dynamic weight is positively correlated with the deviation convergence speed.

[0013] Optionally, the step of tracking the changes of the feature deviation vector in multiple adjacent production cycles and calculating the deviation convergence speed of the generated feature deviation vector includes: obtaining the feature deviation vectors in multiple adjacent production cycles and calculating the magnitude of each feature deviation vector to form a magnitude time series; performing trend analysis on the magnitude time series to obtain the magnitude change trend; and analyzing the magnitude change based on the magnitude change trend to obtain the deviation convergence speed.

[0014] Optionally, the glue spraying control module includes: a glue spraying parameter storage unit, used to construct a speed-glue spraying parameter mapping table recording the reference glue spraying settings at different speeds; a glue spraying parameter acquisition unit, used to acquire the reference glue spraying quantity and reference glue spraying timing from the speed-glue spraying parameter mapping table according to the real-time conveying speed; a glue spraying parameter compensation unit, used to perform delay compensation on the reference glue spraying timing in combination with the mechanical transmission parameters of the packaging machine to generate reference glue spraying parameters; and a control command generation unit, used to adjust the reference glue spraying parameters using the comprehensive dynamic compensation parameters and, in combination with the reference glue spraying quantity, generate the final glue spraying control command.

[0015] Based on the same inventive concept, the present invention also provides a glue spraying control device for a carton packaging machine, the device comprising any of the glue spraying control systems described above for a carton packaging machine.

[0016] Compared with the prior art, the present invention has the following advantages: 1. This invention constructs a composite control architecture that combines feedforward and feedback, which can simultaneously cope with predictable system dynamic disturbances and unpredictable random quality drift. Feedforward control performs forward compensation based on speed changes, suppressing glue spraying deviations during equipment start-up, shutdown, and speed change processes. Feedback control performs closed-loop correction based on actual glue spraying quality, ensuring long-term production stability, thereby achieving control over the glue spraying process. 2. This invention achieves adaptive control strategy by assigning dynamic weights to feedforward and feedback compensation; the system can evaluate in real time the dominance of speed disturbance and the effectiveness of feedback control under the current operating conditions, and adjust the contribution of the two control strategies accordingly, so that the control system can always respond in the optimal way when facing complex and ever-changing production environments, taking into account both the speed and accuracy of control, and enhancing the robustness of the system. 3. This invention uses multi-dimensional feature vectors based on image analysis to quantify the quality of adhesive spraying, incorporating multiple key indicators such as adhesive line width, continuity, and centerline offset into closed-loop control. Compared with monitoring a single indicator, this comprehensive evaluation method can diagnose the root cause of adhesive spraying defects, making feedback adjustment more targeted and effective, thereby achieving the management and improvement of adhesive spraying quality. 4. By setting a threshold for the rate of change of speed, this invention ensures that complex compensation control is activated only when necessary, avoiding overreaction to minor fluctuations, reducing the computational load on the system, and improving operating efficiency. At the same time, by establishing a mapping table between speed and reference glue spraying parameters and combining it with mechanical delay compensation, an accurate and reliable operating baseline is provided for the entire dynamic control, ensuring the basic accuracy of control command generation and the overall stability of the system.

[0017] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a framework diagram of a glue spraying control system for a carton packaging machine according to an embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram of the adhesive spraying control system of a carton packaging machine according to an embodiment of the present invention.

[0021] Figure 3 This is a comparison chart of the feedback control deviation convergence effect in an embodiment of the present invention. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Reference Figure 1 One embodiment of the present invention proposes a glue spraying control system for a carton packaging machine. It adopts a control strategy that combines feedforward and feedback, and dynamically weights and fuses the feedforward and feedback compensations according to the dynamic status of the system. This approach can balance fast response and accurate correction, thereby improving the dynamic performance and steady-state accuracy of glue spraying control.

[0024] The system described in this embodiment specifically includes: Speed ​​monitoring module, image acquisition module, feedforward control module, feedback control module, fusion processing module, and glue spraying control module.

[0025] This invention uses a speed monitoring module to sense changes in conveyor speed in real time and inputs this as a disturbance signal into a feedforward control module. This allows the system to predict the impact of speed fluctuations on the glue spraying position and perform proactive compensation. Simultaneously, the system uses an image acquisition module to acquire images of the actual glue line after spraying. A feedback control module performs quality feature analysis on the images and compares the analysis results with a preset ideal target to generate feedback compensation parameters for correcting deviations. A fusion processing module dynamically adjusts the weights of feedforward and feedback compensation in the final control decision based on the drastic changes in the current conveyor speed and the actual effect of feedback control, fusing them into a comprehensive dynamic compensation parameter. Finally, the glue spraying control module generates baseline glue spraying parameters based on the real-time speed and uses this comprehensive dynamic compensation parameter to fine-tune them, generating the final control command to control the glue spraying process.

[0026] By introducing feedforward control, this system can suppress the impact of speed disturbances caused by predictable factors such as the start-up, shutdown, and speed changes of the packaging machine on the glue spraying quality, thus improving the dynamic response performance of the control system and the glue spraying accuracy under non-steady-state conditions. The feedback control loop, through closed-loop monitoring and correction of actual glue spraying results, compensates for quality drift caused by unpredictable and slowly changing factors such as glue viscosity variations, nozzle wear, and environmental factors, ensuring the long-term stability of the system and the consistency of product quality. The dynamic weighted fusion mechanism achieves complementary advantages and intelligent synergy between the two control strategies, enabling the system to automatically select the optimal control mode under different operating conditions. This allows for rapid response to sudden disturbances and precise correction of steady-state errors, ultimately comprehensively improving the overall level and pass rate of glue spraying for carton packaging, and enhancing the automation and robustness of the production process.

[0027] The speed monitoring module is used to obtain the real-time conveying speed of the glue strip box to be sprayed, and to analyze the real-time conveying speed to generate speed change status parameters. Specifically, in this embodiment, the speed monitoring module serves as the trigger and input link for the entire glue spraying control system of the carton packaging machine. Its core task is to determine whether the operating status of the conveying system is stable and to initiate subsequent feedforward and feedback fusion control processes when speed fluctuations occur. This module works collaboratively through multiple internally integrated functional units to achieve accurate monitoring and status judgment of the conveying speed.

[0028] Optionally, such as Figure 2 As shown, the speed monitoring module includes: The conveying monitoring unit is used to obtain the real-time conveying speed of the glue strip box to be sprayed; A rate of change monitoring unit is used to perform differential calculations on the real-time conveying speed to obtain the rate of change of speed; The control start unit is used to start the control system when the absolute value of the speed change rate exceeds a preset stability threshold, and to use the speed change rate as a speed change state parameter.

[0029] Specifically, the conveying monitoring unit is responsible for continuously acquiring the real-time conveying speed of the current glue-to-be-sprayed strip box. In actual operation, this unit is usually connected to sensors such as encoders installed on the main drive shaft or driven wheel of the packaging machine conveyor belt. By analyzing the pulse signals output by the sensors, high-resolution and real-time speed data is calculated.

[0030] Next, the rate of change monitoring unit receives and processes the real-time conveying speed sequence from the conveying monitoring unit. To quantify the severity of speed changes, this unit performs a differential operation on the real-time conveying speed to obtain the rate of change, i.e., the acceleration or deceleration of the conveying system. In a digital control system, this differential operation is typically achieved by subtracting the speed values ​​from two consecutive sampling times and dividing by the sampling time interval. The calculation can be expressed as: , in, It is the rate of change of velocity at the current moment. It is the real-time transmission speed at the current sampling moment. It is the real-time transmission speed at the previous sampling time. It is the time interval for the system to perform velocity sampling.

[0031] Finally, the control activation unit, acting as the decision-making body, evaluates the speed change rate. This unit takes the absolute value of the speed change rate calculated by the rate change monitoring unit and compares it with a preset stability threshold. This stability threshold is an empirical value pre-set based on the allowable speed fluctuation range of the packaging machine under stable operating conditions. When the absolute value of the speed change rate exceeds this stability threshold, it indicates that the conveying system is undergoing a significant acceleration or deceleration process, which is highly likely to cause deviations in the subsequent glue spraying quality. At this time, the control activation unit will immediately activate the entire glue spraying control system and output the currently calculated speed change rate as a speed change state parameter to the subsequent feedforward control module, so that the system can proactively compensate for this impending speed disturbance. If the speed change rate does not exceed the stability threshold, the system determines that the current operating state is stable and does not initiate complex compensation control, thereby saving system computing resources.

[0032] The image acquisition module is used to acquire images of the glue lines on the glue strip boxes that have been sprayed before the current glue strip box and generate real-time glue line image data; Specifically, the image acquisition module takes pictures of each strip box that has just finished being glued by a high-speed industrial camera set downstream of the glue spraying station, thereby acquiring glue line images on the previously glued strip boxes and converting them into digital real-time glue line image data as the basis for subsequent analysis.

[0033] The feedforward control module is used to calculate the feedforward compensation parameters based on the speed change state parameters; Specifically, in this embodiment, the feedforward control module aims to perform predictive open-loop compensation based on the speed change parameters provided by the speed monitoring module, in order to proactively eliminate the potential impact of conveyor speed fluctuations on adhesive spraying quality. The implementation of this module relies on the orderly collaboration of several internal units.

[0034] Optionally, the feedforward control module includes: The feedforward relation storage unit is used to establish a feedforward mapping relation library that describes the correspondence between velocity changes and compensation amounts; The compensation retrieval unit is used to input the velocity change state parameters into the feedforward mapping relationship library and retrieve the compensation coefficients. The feedforward parameter calculation unit is used to perform calculations using the compensation coefficient and the real-time conveying speed to generate feedforward compensation parameters.

[0035] Specifically, the core of the feedforward relation storage unit is the pre-established and stored feedforward mapping relation library. This library forms the knowledge base of this control strategy, and it was obtained through extensive experimental calibration and data analysis of the variation in adhesive spraying quality under different speed variations of the packaging machine. This library is essentially a data table or function model that precisely describes the nonlinear correspondence between the speed variation state parameters, i.e., the speed change rate, and the compensation amount required for adhesive spraying control. Specifically, it maps different speed change rate values ​​to a specific compensation coefficient.

[0036] When the speed monitoring module detects a significant speed change and outputs the speed change status parameter, the compensation retrieval unit immediately activates. This unit uses the received speed change status parameter, i.e., the speed change rate, as a query index to search a pre-defined feedforward mapping relation library. Through table lookup or function calculation, this unit can quickly obtain a compensation coefficient that precisely matches the current speed change rate. To ensure control smoothness, when the input speed change rate value lies between two discrete data points in the library, the unit can use algorithms such as linear interpolation to calculate the compensation coefficient.

[0037] Finally, the feedforward parameter calculation unit is responsible for generating the final feedforward compensation parameters. This unit receives the compensation coefficients output by the compensation retrieval unit and simultaneously obtains the real-time conveying speed of the glue-to-be-sprayed strip box provided by the speed monitoring module. It uses these two inputs to perform calculations and generate the feedforward compensation parameters for directly adjusting the glue-spraying actuator. : , in, For feedforward compensation parameters, it represents a specific physical adjustment amount, which is dimensionless, such as the amount of advance or delay in glue spraying time, or the amount of increase or decrease in glue spraying amount; These are the compensation coefficients for the corresponding adjustment amounts retrieved from the feedforward mapping relation library, and are dimensionless. It is the real-time delivery speed. This is the standard real-time conveying speed. The physical meaning of this calculation is to dynamically scale a basic compensation factor based on acceleration, which characterizes the degree of disturbance, according to the current actual conveying speed, thereby calculating a compensation value that is most suitable for the current operating conditions.

[0038] The feedback control module is used to perform quality feature analysis on the real-time glue line image data to obtain the actual glue line feature vector, and compare and analyze the actual glue line feature vector with the preset target glue line quality template to generate feedback compensation parameters. Specifically, in this embodiment, the feedback control module performs closed-loop correction based on the actual glue spraying results. It complements the feedforward control module, jointly ensuring the stability of the glue spraying quality. This process begins with the precise operation of the image acquisition module.

[0039] Optionally, the feedback control module includes: The glue spraying feature extraction unit is used to extract the glue line width, glue line continuity and glue line centerline offset from the real-time glue line image data to form the actual glue line feature vector. The deviation calculation unit is used to perform a vector subtraction operation between the actual glue line feature vector and the target feature vector in the preset target glue line quality template to obtain the feature deviation vector. The feedback parameter calculation unit is used to calculate and generate feedback compensation parameters based on the feature deviation vector.

[0040] Specifically, upon receiving real-time glue line image data, the glue spraying feature extraction unit performs in-depth processing on the image data. Using a series of image processing algorithms, including edge detection, image segmentation, and morphological analysis, the unit accurately identifies the glue line region from the complex background. Subsequently, it performs multi-dimensional quantitative analysis on this region, extracting three key quality indicators. The first is the glue line width, obtained by measuring the vertical distance between the two edges of the glue line at multiple locations and calculating their average or statistical distribution. The second is the glue line continuity, detected by analyzing the connectivity of the glue line pixels to identify any breaks or gaps, and quantified as a continuity score or interruption length. The third is the glue line centerline offset, obtained by calculating the average or maximum deviation distance between the geometric centerline of the glue line and the preset ideal glue spraying baseline on the cartridge. These three quantitative indicators together constitute a comprehensive glue line feature vector that fully characterizes the current glue spraying quality. It can be represented as: , in, Represents the actual width of the adhesive line. Represents the actual continuity of the adhesive line. This represents the actual offset of the glue line centerline.

[0041] Next, the deviation calculation unit compares this actual adhesive line feature vector with a preset target adhesive line quality template in the system. This template contains a target feature vector. Each component This represents the standard values ​​for the glue line width, continuity, and centerline offset under ideal conditions. This unit calculates the deviation between the actual result and the ideal target by performing vector subtraction, generating a feature deviation vector. : , Each component of this characteristic deviation vector intuitively reflects the degree and direction of deviation of the adhesive spraying quality in the corresponding dimension.

[0042] Finally, based on this characteristic deviation vector, the feedback parameter calculation unit performs calculations using a specific control algorithm to generate a feedback compensation parameter for correcting subsequent glue spraying operations. This parameter is a specific adjustment instruction that will be used to adjust relevant settings of the glue spraying system, such as glue spraying pressure, glue spraying valve opening time, or nozzle position, in order to eliminate or reduce the deviation detected this time in the next production cycle.

[0043] Optionally, calculating and generating feedback compensation parameters based on the feature deviation vector includes: Perform proportional-integral-differential operations on the feature deviation vector to generate a preliminary compensation value; The initial compensation value is limited to ensure that it remains within the safe operating range of the actuator. The output value after amplitude limiting is used as the feedback compensation parameter.

[0044] Specifically, the first step is to perform proportional-integral-derivative (PID) operations on the characteristic deviation vector output by the deviation calculation unit. Since the characteristic deviation vector is a multi-dimensional vector containing multiple components such as glue line width, glue line continuity, and glue line centerline offset, the PID operation on this vector actually implements an independent PID control strategy for each component. For any component of the characteristic deviation vector... Its corresponding preliminary compensation value The calculation follows the following control law: , in, This is for that component. The generated preliminary compensation value; It is the corresponding component value of the feature deviation vector in the current production cycle, representing the current deviation; It is the cumulative sum of historical deviations, used to eliminate steady-state errors; It is the rate of change of the deviation within adjacent periods, used to predict deviation trends and suppress oscillations. , and These are the proportional, integral, and differential gain coefficients pre-tuned for the specific quality characteristic, such as width, continuity, or offset. By performing this operation on each component of the characteristic deviation vector, the system can generate a set of preliminary compensation values ​​for issues such as width, continuity, and offset.

[0045] Next, the generated preliminary compensation values ​​are limited. The preliminary compensation values ​​generated by the PID calculations may theoretically exceed the physical capabilities of the actuator, for example, requiring the opening pressure of the glue spray valve to exceed its maximum bearing pressure, or requiring the nozzle to move faster than its maximum speed. To prevent this, each preliminary compensation value needs to be safety-checked. The system compares it to the preset upper and lower limits of the actuator's safe operating range. If the preliminary compensation value exceeds this range, it is forcibly set to the nearest boundary value. This limiting process ensures that all control commands remain within the executable and safe range of the hardware, protecting the equipment from potential damage.

[0046] Finally, the output value after amplitude limiting is used as the feedback compensation parameter. This set of verified and limited compensation values ​​constitutes the final feedback compensation parameter. It will be passed to the fusion processing module. This parameter or set of parameters is the final output of the feedback control loop, and is a direct, quantitative, and safe correction instruction based on the actual glue spraying results.

[0047] The fusion processing module is used to assign dynamic weights to the feedforward compensation parameters and the feedback compensation parameters according to the velocity change state parameters, and to perform fusion processing on the feedforward compensation parameters and the feedback compensation parameters based on the dynamic weights to generate comprehensive dynamic compensation parameters. Optionally, the fusion processing module includes: The weight calculation unit is used to assign dynamic weights to the feedforward compensation parameter and the feedback compensation parameter according to the velocity change state parameter and the feature deviation vector, wherein the dynamic weights include a first weight of the feedforward compensation parameter and a second weight of the feedback compensation parameter; The weighted calculation unit is used to multiply the feedforward compensation parameter by the first weight to obtain a weighted feedforward parameter; and to multiply the feedback compensation parameter by the second weight to obtain a weighted feedback parameter; and to perform a summation operation on the weighted feedforward parameter and the weighted feedback parameter to generate a comprehensive dynamic compensation parameter.

[0048] Specifically, the weight calculation unit first dynamically assigns weights to the feedforward compensation parameters and the feedback compensation parameters based on the current dynamic state of the system. This unit receives two key inputs: the speed change state parameters from the speed monitoring module and the characteristic deviation vector from the feedback control module. Based on these two inputs, it calculates the first weight and the second weight in real time. The first weight is assigned to the feedforward compensation parameters, and the second weight is assigned to the feedback compensation parameters. These weights change dynamically, reflecting whether, under the current operating conditions, the system should focus more on the rapid response of the feedforward or on the precise correction of the feedback.

[0049] Subsequently, the weighted calculation unit performs a fusion calculation of the compensation parameters. First, it multiplies the feedforward compensation parameters obtained from the feedforward control module with the first weight assigned by the weight calculation unit to obtain the weighted feedforward parameters. Simultaneously, it multiplies the feedback compensation parameters obtained from the feedback control module with the second weight to obtain the weighted feedback parameters. Finally, the unit sums these two weighted parameters to generate the final comprehensive dynamic compensation parameters. , in, These are the generated comprehensive dynamic compensation parameters, which will serve as the final adjustment amount. It is the first weight assigned to the feedforward compensation parameters. It is calculated in real time by the weight calculation unit based on the velocity change state parameters and characteristic deviation vector, and is a dimensionless coefficient. These are the feedforward compensation parameters calculated by the feedforward control module. It is the second weight assigned to the feedback compensation parameter, which is also calculated by the weight calculation unit and is a dimensionless coefficient. These are the feedback compensation parameters calculated by the feedback control module. Among them, the feedforward compensation parameters... With feedback compensation parameters These represent the same type of adjustment amount, such as the adjustment amount for the glue spraying timing.

[0050] Optionally, assigning dynamic weights to the feedforward compensation parameter and the feedback compensation parameter based on the velocity change state parameter and the feature deviation vector includes: Based on the magnitude of the rate of change of velocity in the velocity change state parameters, a first weight is assigned to the feedforward compensation parameter, wherein the first weight is positively correlated with the magnitude of the rate of change of velocity. The changes of the feature deviation vector in multiple adjacent production cycles are tracked, and the deviation convergence speed of the generated feature deviation vector is calculated. Based on the deviation convergence speed, a second weight is assigned to the feedback compensation parameter, wherein the second dynamic weight is positively correlated with the deviation convergence speed.

[0051] Specifically, the system determines the value of the first weight based on the speed change status parameters obtained from the speed monitoring module, specifically the magnitude of the speed change rate. This weight is positively correlated with the absolute value of the speed change rate. This means that when the conveying speed of the carton changes drastically, i.e., the absolute value of the speed change rate is large, the system determines that the current main disturbance comes from a predictable dynamic disturbance. In this case, the system will assign a larger first weight to the feedforward compensation parameter to enhance the rapid response and active compensation capability of the feedforward control. Conversely, when the conveying system operates smoothly and the absolute value of the speed change rate is small, the first weight is reduced accordingly to decrease the intervention degree of the feedforward control.

[0052] Simultaneously, the system continuously tracks the changes in the feature deviation vector output by the feedback control module over multiple adjacent production cycles to calculate the deviation convergence rate. To achieve this, the system first obtains the feature deviation vectors from the most recent production cycles and calculates the magnitude of each vector. The magnitude of the vector is a scalar, representing the overall degree to which the glue spraying quality deviates from the ideal state within that cycle. This forms a time series of the magnitude. By performing trend analysis on this time series, the system can obtain a quantified deviation convergence rate.

[0053] Subsequently, the system assigns a second weight to the feedback compensation parameter based on the calculated deviation convergence rate. This second weight is positively correlated with the deviation convergence rate. In other words, if the deviation is converging rapidly, it indicates that the feedback control strategy is currently very effective, and the system will assign a higher second weight to the feedback compensation parameter to trust and strengthen its corrective effect. Conversely, if the deviation converges slowly or even diverges, it indicates that the feedback control is ineffective, and the second weight will be reduced to prevent inappropriate feedback adjustments from causing further disturbances to the system.

[0054] Optionally, tracking the changes of the feature deviation vector over multiple adjacent production cycles and calculating the deviation convergence speed for generating the feature deviation vector includes: Obtain feature deviation vectors within multiple adjacent production cycles, and calculate the magnitude of each feature deviation vector to form a magnitude-time sequence; Trend analysis was performed on the time series of the modulus to obtain the trend of modulus change; The deviation convergence rate is obtained by analyzing the change in the modulus based on the trend of modulus change.

[0055] Specifically, the system retrieves the feature deviation vectors generated by the deviation calculation unit in multiple adjacent production cycles from memory. Let the feature deviation vector be in the i-th production cycle. ,in , , These represent the deviations in glue line width, continuity, and centerline offset within the given period. To transform this multi-dimensional deviation vector into a single index that comprehensively reflects the overall magnitude of the deviation, the system needs to calculate the magnitude of each characteristic deviation vector. The magnitude of the vector, also known as its Euclidean norm, is obtained by calculating the square root of the sum of the squares of the vector's components. The formula is as follows: , in, It is a square root function. This represents the magnitude of the feature deviation vector. By performing this operation on the feature deviation vectors of N consecutive production cycles, the system will obtain a magnitude-time sequence consisting of N magnitude values. This sequence visually demonstrates how the overall deviation in adhesive spraying quality changes over time.

[0056] Next, trend analysis is performed on this long-term modulus series to extract the trend of modulus changes. The most direct method is to calculate the rate of change of modulus between adjacent periods, but this is easily affected by noise from a single measurement. To obtain a more robust trend judgment, the system can use the moving average method to smooth the long-term modulus series, or use the least squares method to perform linear regression fitting on the data points in the most recent period. Through linear regression, a straight line that best represents the recent trend of modulus changes can be obtained, and the slope of this line is the trend of modulus changes. A negative slope indicates that the overall deviation is decreasing, while a positive slope indicates that the deviation is increasing.

[0057] Finally, based on the obtained trend of modulus length variation, the variation of modulus length is analyzed, and the deviation convergence rate is finally obtained. In the simplest implementation, the slope of the modulus length variation trend can be directly used as a quantitative indicator of the deviation convergence rate. A large negative slope means that the deviation is converging rapidly, while a slope close to zero indicates that the system is tending to stabilize or converges slowly. If the slope is positive, it indicates that the system may be in a divergent state. This calculated deviation convergence rate is an indicator that can objectively and quantitatively reflect the dynamic performance of the feedback control system under the current operating conditions, such as... Figure 3 The feedback control shown demonstrates the corrective effect.

[0058] The glue spraying control module is used to generate reference glue spraying parameters based on the real-time conveying speed, and to adjust the reference glue spraying parameters using the comprehensive dynamic compensation parameters to generate the final glue spraying control command.

[0059] Optionally, the glue spraying control module includes: The glue spraying parameter storage unit is used to construct a speed-glue spraying parameter mapping table that records the baseline glue spraying settings at different speeds. The glue spraying parameter acquisition unit is used to obtain the reference glue spraying amount and reference glue spraying timing from the speed-glue spraying parameter mapping table according to the real-time conveying speed; The glue spraying parameter compensation unit is used to perform delay compensation on the reference glue spraying timing in combination with the mechanical transmission parameters of the packaging machine to generate reference glue spraying parameters; The control command generation unit is used to adjust the reference glue spraying parameters using the comprehensive dynamic compensation parameters, and generate the final glue spraying control command in combination with the reference glue spraying amount.

[0060] Specifically, the glue spraying parameter storage unit, serving as the system's foundational knowledge base, pre-builds and stores a detailed speed-glue spraying parameter mapping table. This table was established during the equipment commissioning phase through extensive experimental calibration at different stable conveying speeds. It records the baseline glue spraying settings that achieve ideal glue spraying quality at various stable speeds. These settings primarily include the baseline glue spraying volume and the baseline glue spraying timing. The baseline glue spraying volume typically refers to the opening duration of the glue spraying valve or the glue spraying pressure, determining the volume of glue sprayed; while the baseline glue spraying timing specifies the start time of the glue spraying action relative to the trigger signal of the strip box position.

[0061] When the glue-to-be-sprayed strip enters the working area, the glue-spraying parameter acquisition unit immediately starts. It obtains the current real-time conveying speed from the speed monitoring module and uses this speed as an index to look up the speed-glue-spraying parameter mapping table. Through the table lookup operation, possibly supplemented by a linear interpolation algorithm to handle speed values ​​that are interrupted in the table, this unit can quickly obtain the reference glue-spraying amount and reference glue-spraying timing that match the current speed.

[0062] Next, the glue spraying parameter compensation unit performs a preliminary static compensation on the acquired baseline glue spraying timing. This step aims to eliminate the inherent physical delays of the system. This unit combines pre-measured and stored mechanical transmission parameters of the packaging machine, such as the electrical and mechanical response time from the controller issuing a command to the actual opening of the glue spraying valve, and the conveying time corresponding to the physical distance of the strip from the position detection sensor to the glue spraying head. By performing precise delay compensation on the baseline glue spraying timing, this unit generates a more accurate baseline glue spraying parameter that takes into account the physical characteristics of the equipment itself.

[0063] Finally, the control command generation unit receives the reference glue spraying parameters after static delay compensation and the comprehensive dynamic compensation parameters. It uses these comprehensive dynamic compensation parameters to dynamically fine-tune the reference glue spraying parameters. This adjustment primarily affects the glue spraying timing; by algebraically superimposing the reference glue spraying parameters and the comprehensive dynamic compensation parameters, a fully compensated glue spraying timing is generated. Subsequently, the unit combines this final glue spraying timing with the reference glue spraying amount previously obtained from the mapping table, packaging it to generate a complete final glue spraying control command that includes when to spray, for how long, or at what pressure, and sends it to the underlying programmable logic controller or motion controller to drive the glue spraying valve to perform its action.

[0064] Based on the same inventive concept, the present invention also provides a glue spraying control device for a carton packaging machine, the device comprising any of the glue spraying control systems described above for a carton packaging machine.

[0065] Example 1 To verify the feasibility of this invention in practice, it was applied to a carton packaging production line. The carton packaging machine control system uses an encoder mounted on the main drive shaft of the conveyor belt as a speed monitoring module to acquire the real-time conveying speed of the cartons; a high-speed industrial camera is installed downstream of the glue spraying station as an image acquisition module to capture images of the glue lines on the glued cartons. When the packaging machine starts or changes speed, the method of this invention begins to execute.

[0066] For example, during a single equipment startup, the conveyor speed linearly accelerates from 0 m / s to a stable 2.5 m / s within 2 seconds, and the speed change rate monitoring unit calculates the speed change rate to be 1.25 m / s. 2 Its absolute value far exceeds the preset 0.1 m / s 2 The stability threshold is determined. The control initiation unit immediately triggers the entire compensation control process and transmits the rate of change of velocity as a velocity change state parameter to the feedforward control module. The feedforward control module, based on a preset feedforward mapping database, retrieves the value corresponding to 1.25 m / s. 2 The corresponding compensation coefficient is calculated, and the feedforward compensation parameter is calculated in combination with the real-time speed. This parameter is mainly used to pre-adjust the glue spraying timing to offset the glue spraying position lag caused by acceleration.

[0067] Meanwhile, the image acquisition module continuously acquires images of the glue lines from the previously sprayed glue strips. The glue feature extraction unit of the feedback control module extracts the glue line width, continuity, and centerline offset from the images, forming an actual glue line feature vector. During stable operation, due to slight nozzle wear, the system detects a continuous +0.3mm offset in the glue line centerline. The deviation calculation unit compares this actual feature vector with the target feature vector to generate a feature deviation vector. The feedback parameter calculation unit uses PID calculations to generate feedback compensation parameters designed to correct this +0.3mm steady-state error.

[0068] During the equipment startup phase, the velocity change rate is as high as 1.25 m / s. 2 The weighting calculation unit assigns a first weight of 0.85 to the feedforward compensation parameters and a second weight of 0.15 to the feedback compensation parameters, which aim to correct steady-state errors, ensuring that the system prioritizes responses to severe dynamic disturbances. When the equipment enters a stable operating state, the rate of change of velocity drops to 0.05 m / s². 2 Below the threshold, the feedforward compensation weight drops to near 0, while the feedback compensation weight increases accordingly, shifting the system's control focus to precisely eliminate steady-state deviations caused by slow variables such as nozzle wear. During the correction of a +0.3mm offset, the system tracked the magnitude of the characteristic deviation vector decreasing from 0.3 to 0.1 within adjacent cycles, calculating a higher deviation convergence rate. Therefore, a higher second weight (e.g., 0.9) was assigned to the feedback compensation parameter to accelerate error convergence.

[0069] Finally, the glue spraying control module obtains the baseline glue spraying parameters from the speed-glue spraying parameter mapping table based on the real-time conveying speed, and uses the comprehensive dynamic compensation parameters generated by the fusion processing module to fine-tune them in real time, generating the final glue spraying control command to drive the glue spraying valve to execute precisely.

[0070] It should be noted that the electrical connections between the various units described above do not necessarily represent direct or indirect connections. Any indirect connection method can be applied to the embodiments of the present invention as long as it achieves the purpose of the present invention. The above descriptions are merely exemplary embodiments of the present invention and should not be construed as limiting the scope of the present invention.

[0071] All equivalent changes and modifications made in accordance with the teachings of this invention are still within the scope of this invention. Those skilled in the art will readily conceive of other embodiments of this invention upon considering the specification and the disclosure of practical truth. This application is intended to cover any variations, uses, or adaptations of this invention that follow the general principles of this invention and include common knowledge or conventional techniques in the art not described herein.

Claims

1. A glue spraying control system for a carton packer, characterized by, The system includes: The speed monitoring module is used to obtain the real-time conveying speed of the glue strip box to be sprayed, and to analyze the real-time conveying speed to generate speed change status parameters. The image acquisition module is used to acquire images of the glue lines on the glue strip boxes that have been sprayed before the current glue strip box and generate real-time glue line image data; The feedforward control module is used to calculate the feedforward compensation parameters based on the speed change state parameters; The feedback control module is used to perform quality feature analysis on the real-time glue line image data to obtain the actual glue line feature vector, and compare and analyze the actual glue line feature vector with the preset target glue line quality template to generate feedback compensation parameters. The fusion processing module is used to assign dynamic weights to the feedforward compensation parameters and the feedback compensation parameters according to the velocity change state parameters, and to perform fusion processing on the feedforward compensation parameters and the feedback compensation parameters based on the dynamic weights to generate comprehensive dynamic compensation parameters. The glue spraying control module is used to generate reference glue spraying parameters based on the real-time conveying speed, and to adjust the reference glue spraying parameters using the comprehensive dynamic compensation parameters to generate the final glue spraying control command.

2. The glue spraying control system of a carton packing machine according to claim 1, characterized in that, The speed monitoring module includes: The conveying monitoring unit is used to obtain the real-time conveying speed of the glue strip box to be sprayed; A rate of change monitoring unit is used to perform differential calculations on the real-time conveying speed to obtain the rate of change of speed; The control start unit is used to start the control system when the absolute value of the speed change rate exceeds a preset stability threshold, and to use the speed change rate as a speed change state parameter.

3. The glue spraying control system of a carton packing machine according to claim 2, characterized in that, The feedforward control module includes: The feedforward relation storage unit is used to establish a feedforward mapping relation library that describes the correspondence between velocity changes and compensation amounts; The compensation retrieval unit is used to input the velocity change state parameters into the feedforward mapping relationship library and retrieve the compensation coefficients. The feedforward parameter calculation unit is used to perform calculations using the compensation coefficient and the real-time conveying speed to generate feedforward compensation parameters.

4. The glue spraying control system of a carton packing machine according to claim 3, characterized in that, The feedback control module includes: The glue spraying feature extraction unit is used to extract the glue line width, glue line continuity and glue line centerline offset from the real-time glue line image data to form the actual glue line feature vector. The deviation calculation unit is used to perform a vector subtraction operation between the actual glue line feature vector and the target feature vector in the preset target glue line quality template to obtain the feature deviation vector. The feedback parameter calculation unit is used to calculate and generate feedback compensation parameters based on the feature deviation vector.

5. The glue spraying control system of a carton packing machine according to claim 4, characterized in that, The calculation of the feedback compensation parameters based on the feature deviation vector includes: Perform proportional-integral-differential operations on the feature deviation vector to generate a preliminary compensation value; The initial compensation value is limited to ensure that it remains within the safe operating range of the actuator. The output value after amplitude limiting is used as the feedback compensation parameter.

6. The glue spraying control system of a carton packing machine according to claim 4, characterized in that, The fusion processing module includes: The weight calculation unit is used to assign dynamic weights to the feedforward compensation parameter and the feedback compensation parameter according to the velocity change state parameter and the feature deviation vector, wherein the dynamic weights include a first weight of the feedforward compensation parameter and a second weight of the feedback compensation parameter; The weighted calculation unit is used to multiply the feedforward compensation parameter by the first weight to obtain a weighted feedforward parameter; and to multiply the feedback compensation parameter by the second weight to obtain a weighted feedback parameter; and to perform a summation operation on the weighted feedforward parameter and the weighted feedback parameter to generate a comprehensive dynamic compensation parameter.

7. The glue spraying control system of a carton packing machine according to claim 6, characterized in that, The step of assigning dynamic weights to the feedforward compensation parameter and the feedback compensation parameter based on the velocity change state parameter and the feature deviation vector includes: Based on the magnitude of the rate of change of velocity in the velocity change state parameters, a first weight is assigned to the feedforward compensation parameter, wherein the first weight is positively correlated with the magnitude of the rate of change of velocity. The changes of the feature deviation vector in multiple adjacent production cycles are tracked, and the deviation convergence speed of the generated feature deviation vector is calculated. Based on the deviation convergence speed, a second weight is assigned to the feedback compensation parameter, wherein the second dynamic weight is positively correlated with the deviation convergence speed.

8. The glue spraying control system for a carton packaging machine according to claim 7, characterized in that, The step of tracking the changes of the feature deviation vector over multiple adjacent production cycles and calculating the deviation convergence speed of the generated feature deviation vector includes: Obtain feature deviation vectors within multiple adjacent production cycles, and calculate the magnitude of each feature deviation vector to form a magnitude-time sequence; Trend analysis was performed on the time series of the modulus to obtain the trend of modulus change; The deviation convergence rate is obtained by analyzing the change in the modulus based on the trend of modulus change.

9. The glue spraying control system for a carton packaging machine according to claim 1, characterized in that, The adhesive spraying control module includes: The glue spraying parameter storage unit is used to construct a speed-glue spraying parameter mapping table that records the baseline glue spraying settings at different speeds. The glue spraying parameter acquisition unit is used to obtain the reference glue spraying amount and reference glue spraying timing from the speed-glue spraying parameter mapping table according to the real-time conveying speed; The glue spraying parameter compensation unit is used to perform delay compensation on the reference glue spraying timing in combination with the mechanical transmission parameters of the packaging machine to generate reference glue spraying parameters; The control command generation unit is used to adjust the reference glue spraying parameters using the comprehensive dynamic compensation parameters, and generate the final glue spraying control command in combination with the reference glue spraying amount.

10. A glue spraying control device for a carton packaging machine, characterized in that, The device includes the glue spraying control system for the carton packaging machine according to any one of claims 1 to 9.

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