A method and system for coordinated temperature and pressure control in the continuous foaming process of polyurethane sandwich panels

Abstract

This invention discloses a method and system for coordinated temperature and pressure control during the continuous foaming process of polyurethane sandwich panels, relating to the field of automatic control technology. The method includes: collecting temperature and pressure monitoring data from multiple spatial locations distributed along the material movement direction; constructing a spatiotemporal distribution matrix and extracting temperature and pressure evolution trajectories; identifying the imbalanced spatial locations and spatiotemporal deviations by calculating differences in evolution rates and inflection point times; tracing the propagation path of the spatiotemporal deviations along the panel movement direction, calculating the cumulative effect, and determining the downstream spatial location range; calculating temperature and pressure compensation amounts for the downstream spatial locations; determining the differentiated application time interval based on the difference in their response times; and outputting compensation and control commands to the corresponding control equipment. This invention solves the quality fluctuation problem caused by temperature and pressure imbalance, improving production stability and product quality consistency.

Description

Technical Field

[0001] This invention relates to the field of automatic control technology, specifically to a method and system for temperature and pressure coordinated control of the continuous foaming process of polyurethane sandwich panels. Background Technology

[0002] As an important building insulation material, the temperature and pressure during the continuous foaming production of polyurethane sandwich panels are key process parameters affecting product quality. Temperature changes affect the chemical reaction rate and cell structure formation of polyurethane, while pressure changes directly affect the degree of cell expansion and final density.

[0003] Traditional foaming production employs segmented temperature and pressure control, with each control device operating independently and adjusting based solely on setpoints using open-loop or simple feedback mechanisms. This control method has significant limitations: temperature and pressure control are independent, failing to consider their coupling relationship, making it difficult to coordinately optimize process parameters; the control system only focuses on instantaneous parameter deviations at a single spatial location, lacking a holistic understanding of the spatiotemporal evolution of parameters across the entire production line, and cannot anticipate the cumulative impact of local deviations on downstream processes; compensation adjustments are applied synchronously, failing to consider the different response time characteristics of temperature and pressure, resulting in poor compensation effectiveness.

[0004] In a continuously moving material system, a process deviation at one location propagates downstream as the material moves, creating a cumulative quality fluctuation by combining with local deviations downstream. Temperature primarily affects the foaming process by altering the chemical reaction rate, with a relatively slow and prolonged effect; pressure, on the other hand, directly affects cell expansion, responding rapidly but with a shorter duration. Existing control methods fail to fully utilize these differentiated response characteristics, employing a simultaneous application strategy during compensation adjustments, which significantly diminishes the synergistic effect of temperature and pressure.

[0005] While existing process control technologies include multivariable control and predictive control methods, a systematic solution is still lacking for the spatiotemporal coupling control problem of continuously moving material systems. Summary of the Invention

[0006] The purpose of this invention is to provide a method and system for temperature and pressure coordinated control during the continuous foaming process of polyurethane sandwich panels, aiming to solve at least one of the technical problems existing in the prior art.

[0007] The technical solution of this invention is: a method for coordinated temperature and pressure control in the continuous foaming process of polyurethane sandwich panels, comprising the following steps: Temperature and pressure monitoring data are collected from multiple spatial locations distributed along the material movement direction; A spatiotemporal distribution matrix was constructed using temperature monitoring data and pressure monitoring data, and the temperature evolution trajectory and pressure evolution trajectory at each spatial location were extracted. Calculate the difference in evolution rate and the difference in inflection point between the temperature evolution trajectory and the pressure evolution trajectory to identify the spatial location of the imbalance and the corresponding spatiotemporal deviation. Based on the distribution of the misalignment spatial location along the direction of plate movement, the propagation path of the spatiotemporal deviation is traced along the direction of plate movement. The cumulative effect of the spatiotemporal deviation along the propagation path is calculated, and the downstream spatial location range of the cumulative effect is determined. For each spatial location within the downstream spatial location range, calculate the temperature compensation and pressure compensation required to offset the cumulative effect, and determine the time interval between the application of temperature compensation and pressure compensation based on the response time of temperature compensation and pressure compensation. Based on the temperature compensation amount, pressure compensation amount, and time interval, compensation and control commands are output to the temperature control equipment and pressure control equipment corresponding to the downstream spatial location range.

[0008] A spatiotemporal distribution matrix was constructed using temperature and pressure monitoring data, and the temperature and pressure evolution trajectories at each spatial location were extracted, including: The spatial coordinates of each location in the material movement direction are used as spatial dimension indexes, and the collection time of temperature and pressure monitoring data is used as time dimension indexes. According to the correspondence between location coordinates and collection time, temperature and pressure monitoring data are filled into the corresponding index positions to construct a spatiotemporal distribution matrix. Temperature monitoring data at different collection times corresponding to the same spatial location are extracted from the spatiotemporal distribution matrix and arranged in chronological order of collection times to form the temperature evolution trajectory of each spatial location. Pressure monitoring data at different collection times corresponding to the same spatial location are extracted from the spatiotemporal distribution matrix and arranged in chronological order of collection times to form the pressure evolution trajectory of each spatial location.

[0009] Calculating the difference in evolution rate and inflection point time between the temperature evolution trajectory and the pressure evolution trajectory, and identifying the spatial location of the misalignment and the corresponding spatiotemporal deviation, includes: The transition boundary between the temperature rise and temperature fall segments in the temperature evolution trajectory at each spatial location is identified as the temperature inflection point. The transition boundary between the pressure rise and pressure fall segments in the pressure evolution trajectory is identified as the pressure inflection point. The temporal misalignment between the temperature inflection point and the pressure inflection point at the same spatial location is calculated as the difference in the evolution inflection point. Based on the difference in the inflection point of evolution, the time window between the temperature inflection point and the pressure inflection point is determined, and the difference in the change amplitude of the temperature evolution trajectory and the pressure evolution trajectory within the time window is calculated as the difference in evolution rate. Spatial locations where both the difference in the inflection point of evolution and the difference in the rate of evolution exceed the preset misalignment criteria are identified as misaligned spatial locations. The comprehensive quantitative value of the difference in the inflection point of evolution and the difference in the rate of evolution at the misaligned spatial location is calculated as the corresponding spatiotemporal deviation.

[0010] Based on the distribution of the misalignment spatial location along the board's movement direction, the propagation path of the spatiotemporal deviation is traced along the board's movement direction. The cumulative effect of the spatiotemporal deviation along the propagation path is calculated, and the downstream spatial location range of the cumulative effect is determined, including: Based on the distribution of the misalignment spatial locations in the material movement direction, the misalignment spatial locations are arranged into a propagation sequence. Based on the spatial distance and spatiotemporal deviation between adjacent misalignment spatial locations in the propagation sequence, the transmission intensity of the spatiotemporal deviation between adjacent locations is calculated. Based on the transmission intensity, the propagation path of the spatiotemporal deviation along the material movement direction is constructed. The spatial locations of the misalignment in the propagation sequence are processed sequentially along the propagation path. The spatiotemporal deviation upstream of the current location is attenuated according to the propagation intensity. The attenuated upstream spatiotemporal deviation is superimposed with the spatiotemporal deviation at the current location to obtain the cumulative spatiotemporal deviation at the current location. The cumulative spatiotemporal deviation of each misalignment location in the propagation sequence is taken as the cumulative effect of the spatiotemporal deviation on the propagation path. The peak position is identified from the cumulative effect of the spatiotemporal deviation along the propagation path. The decay process of the cumulative effect is traced from the peak position along the material movement direction until the cumulative effect decays to dissipation. The spatial range between the peak position and the dissipation position is determined as the downstream spatial range of the cumulative effect.

[0011] The calculation of the propagation strength of spatiotemporal deviation between adjacent locations based on the spatial spacing and spatiotemporal deviation between adjacent misalignment locations in the propagation sequence includes: Obtain the spatial distance between adjacent misalignment locations in the propagation sequence, calculate the ratio of the spatial distance to the preset attenuation reference distance, and determine the spatial attenuation coefficient based on the ratio; The spatiotemporal deviation of the adjacent misalignment spatial position pair in the propagation sequence located upstream of the material movement direction is obtained. The spatiotemporal deviation is then used to perform attenuation calculation with the spatial attenuation coefficient to obtain the attenuation transmission amount based on the spatial spacing. Extract the temperature evolution trajectory and pressure evolution trajectory of adjacent misalignment spatial location pairs in the propagation sequence, calculate the gradient difference of temperature evolution trajectory and pressure evolution trajectory between adjacent misalignment spatial location pairs, and calculate the temperature-pressure coupling enhancement factor based on the gradient difference of temperature evolution trajectory and pressure evolution trajectory. Multiplying the attenuation transfer amount based on spatial spacing with the temperature-pressure coupling enhancement factor yields the transfer intensity of spatiotemporal deviation between adjacent locations.

[0012] For each spatial location within the downstream spatial range, calculate the temperature compensation and pressure compensation required to offset the cumulative effect. Based on the response times of the temperature compensation and pressure compensation, determine the time interval between the application of the temperature compensation and the application of the pressure compensation, including: Obtain the cumulative spatiotemporal deviation of each spatial location within the downstream spatial location range, and decompose the cumulative spatiotemporal deviation into temperature dimension deviation component and pressure dimension deviation component; The amount of temperature compensation required to offset the cumulative effect is calculated based on the rate of change of the temperature dimension deviation component and the temperature evolution trajectory, and the amount of pressure compensation required to offset the cumulative effect is calculated based on the rate of change of the pressure dimension deviation component and the pressure evolution trajectory. The time required to offset the temperature dimension deviation component after the temperature compensation is applied is calculated as the response time of the temperature compensation; the time required to offset the pressure dimension deviation component after the pressure compensation is applied is calculated as the response time of the pressure compensation. Calculate the response time difference between the temperature compensation and the pressure compensation, and calculate the spatiotemporal propagation offset based on the response time difference and the material movement speed. Add the response time difference to the time advance corresponding to the spatiotemporal propagation offset to obtain the time interval between the application of the temperature compensation and the application of the pressure compensation.

[0013] Based on the temperature compensation amount, pressure compensation amount, and time interval, compensation and control commands are output to the temperature control equipment and pressure control equipment corresponding to the downstream spatial location range, including: Based on the spatial mapping relationship between each spatial location within the downstream spatial location range and the temperature control equipment and pressure control equipment, determine the temperature control equipment and pressure control equipment corresponding to the downstream spatial location range; For temperature control equipment corresponding to the downstream spatial location range, the application time of temperature compensation is calculated based on the temperature compensation amount and time interval, and the temperature regulation range is calculated based on the control response characteristics of the temperature control equipment and the temperature compensation amount. For pressure control equipment corresponding to the downstream spatial location range, the application time of pressure compensation is calculated based on the pressure compensation amount and time interval, and the pressure regulation range is calculated based on the control response characteristics of the pressure control equipment and the pressure compensation amount. Based on the application time of the temperature compensation amount and the temperature control range, a temperature compensation control command is output to the temperature control equipment corresponding to the downstream spatial location range. Based on the timing of pressure compensation application and the pressure control amplitude, pressure compensation control commands are output to the pressure control equipment corresponding to the downstream spatial location range.

[0014] This invention provides a temperature and pressure coordinated control system for the continuous foaming process of polyurethane sandwich panels, the system comprising: The data acquisition module is used to collect temperature and pressure monitoring data from multiple spatial locations distributed along the material movement direction; The spatiotemporal modeling module is used to construct a spatiotemporal distribution matrix from temperature monitoring data and pressure monitoring data, and to extract the temperature evolution trajectory and pressure evolution trajectory at each spatial location. The imbalance identification module is used to calculate the difference in evolution rate and the difference in inflection point time between the temperature evolution trajectory and the pressure evolution trajectory, and to identify the spatial location of the imbalance and the corresponding spatiotemporal deviation. The propagation analysis module is used to track the propagation path of the spatiotemporal deviation along the direction of the board's movement based on the distribution of the misalignment spatial location in the direction of board movement, calculate the cumulative effect of the spatiotemporal deviation on the propagation path, and determine the downstream spatial location range of the cumulative effect. The compensation calculation module is used to calculate the temperature compensation and pressure compensation required to offset the cumulative effect for each spatial location within the downstream spatial location range, and to determine the time interval between the application of the temperature compensation and the application of the pressure compensation based on the response time of the temperature compensation and the response time of the pressure compensation. The control output module is used to output compensation and control commands to the temperature control equipment and pressure control equipment corresponding to the downstream spatial location range based on the temperature compensation amount, pressure compensation amount and time interval.

[0015] One technical solution provided in this embodiment of the invention is an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps in any of the aforementioned methods.

[0016] One technical solution provided in this embodiment of the invention is a computer-readable storage medium storing computer program instructions, which, when executed by a processor, implement the steps in any of the aforementioned methods.

[0017] This invention achieves a comprehensive understanding of the spatiotemporal evolution of temperature and pressure parameters by constructing a spatiotemporal distribution matrix and extracting temperature and pressure evolution trajectories, overcoming the limitations of traditional single-point control that cannot perceive the overall process state. By calculating the differences in evolution rates and inflection points, the spatial location of imbalances can be identified, accurately pinpointing the location and severity of temperature and pressure imbalances, providing a reliable basis for subsequent precise compensation. By tracking the propagation path of spatiotemporal deviations and calculating cumulative effects, the scope and extent of the impact of local deviations on downstream processes can be predicted, realizing a shift from passive response to proactive prevention in control mode, effectively avoiding the cumulative amplification of quality defects. The differentiated application time interval is determined based on the difference in response time between temperature and pressure compensation, fully utilizing the different mechanisms and response characteristics of temperature and pressure, ensuring that both compensation measures take effect simultaneously at the target location, significantly improving the effectiveness of temperature and pressure coordinated control. Attached Figure Description

[0018] Figure 1 A flowchart of a temperature and pressure coordinated control method for the continuous foaming process of polyurethane sandwich panels provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the temperature and pressure coordinated control system for the continuous foaming process of polyurethane sandwich panels according to an embodiment of the present invention. Detailed Implementation

[0019] like Figure 1 As shown, Figure 1 This is a flowchart of a method for coordinated temperature and pressure control during the continuous foaming process of polyurethane sandwich panels provided in an embodiment of the present invention. The method includes the following steps: Step 101: Collect temperature and pressure monitoring data at multiple spatial locations distributed along the material movement direction.

[0020] Step 102: Construct a spatiotemporal distribution matrix from the temperature monitoring data and the pressure monitoring data, and extract the temperature evolution trajectory and pressure evolution trajectory at each spatial location.

[0021] In some embodiments of the present invention, step 102 may specifically include the following sub-steps: Sub-step 1021: Use the position coordinates of each spatial location in the material movement direction as the spatial dimension index, and the collection time of the temperature monitoring data and pressure monitoring data as the time dimension index. Fill the temperature monitoring data and pressure monitoring data into the corresponding index positions according to the correspondence between the position coordinates and the collection time to construct a spatiotemporal distribution matrix. Sub-step 1022: Extract temperature monitoring data at different collection times corresponding to the same spatial location from the spatiotemporal distribution matrix, and arrange them in chronological order of collection times to form the temperature evolution trajectory of each spatial location. Sub-step 1023: Extract pressure monitoring data at different collection times corresponding to the same spatial location from the spatiotemporal distribution matrix, and arrange them in chronological order of collection times to form the pressure evolution trajectory of each spatial location.

[0022] In the temperature and pressure coordinated control of the continuous foaming process of polyurethane sandwich panels, temperature and pressure monitoring data are collected through multiple monitoring points set along the material movement direction. These monitoring points are evenly distributed along the foaming production line at 0.5m intervals, covering the entire process from raw material injection to molding and discharge. Each monitoring point is equipped with both a temperature sensor and a pressure sensor, with a sensor sampling frequency set to 1Hz to ensure continuous and complete data acquisition. The temperature sensor has a measurement range of 0-200℃ and an accuracy of ±0.1℃; the pressure sensor has a measurement range of 0-10MPa and an accuracy of ±0.01MPa.

[0023] The spatiotemporal distribution matrix is ​​constructed using a two-dimensional array structure, with spatial coordinates as row indices and timestamps as column indices. Spatial coordinates are numbered sequentially according to the actual location of the monitoring points on the production line, starting from the raw material injection point and numbered 1, 2, 3, etc. The time dimension index uses relative timestamps, with the start time of data acquisition as the baseline time point, and subsequent timestamps incrementing by seconds. Temperature and pressure monitoring data are respectively filled into their corresponding spatiotemporal distribution matrices, forming independent temperature and pressure spatiotemporal matrices.

[0024] During matrix filling, each data point is positioned within the matrix based on its spatial coordinates and the time of data acquisition. When data is missing at a particular spatiotemporal location, linear interpolation is used to fill the gap. The interpolation calculation is based on valid data points from adjacent time points to ensure data continuity. The matrix structure is m×n dimensional, where m represents the number of spatial locations and n represents the number of temporal sampling points.

[0025] The extraction of temperature evolution trajectory is achieved by traversing each row of the temperature-space-time matrix, with each row representing a temperature change sequence at a fixed spatial location. The extraction process reads data in ascending order of time index, forming a temperature change curve over time at that location. For monitoring point i, its temperature evolution trajectory contains the temperature values ​​at all acquisition times, arranged in chronological order into a one-dimensional array.

[0026] The method for extracting pressure evolution trajectories is similar to that for temperature evolution trajectories, achieved by traversing the row data of the pressure spatiotemporal matrix. Each spatial location corresponds to a pressure evolution trajectory, reflecting the change in pressure at that location over time. The trajectory data is plotted with time on the x-axis and pressure value on the y-axis, forming a continuous pressure change curve.

[0027] The data preprocessing stage filters the raw monitoring data to remove high-frequency noise and outliers. A moving average filter is used with a window length of 5 sampling points to smooth the temperature and pressure data separately. Outlier identification is based on the 3σ criterion; data points outside the normal range are marked as outliers and replaced.

[0028] The evolution trajectory data structure adopts a time series format, with each trajectory containing two parts: a timestamp and a corresponding numerical value. The trajectory length is determined based on the monitoring duration, typically covering the entire bubble formation cycle. Trajectory data is stored in an array structure for easy subsequent analysis and processing.

[0029] Spatial positioning is determined using a relative coordinate system, with the production line starting point as the origin and a one-dimensional coordinate axis established along the material movement direction. The coordinate value of each monitoring point corresponds to its actual position on the production line, with coordinate accuracy down to the centimeter level. A correlation is established between location information and monitoring data to ensure the spatial positioning accuracy of the data.

[0030] A time synchronization mechanism ensures that data collection at all monitoring points is consistent in time. A unified time base is used, and the clock synchronization error at each monitoring point is controlled to the millisecond level. Timestamps use an absolute time format, including year, month, day, hour, minute, and second information, facilitating data traceability and analysis.

[0031] The data storage format adopts a matrix structure, where each element is located using row and column coordinates. The row coordinates correspond to spatial location numbers, and the column coordinates correspond to time sequence numbers. This storage structure facilitates data extraction by spatial location or time slice, meeting diverse analytical needs.

[0032] Quality control of the evolution trajectory is achieved through data integrity checks, which include the continuity of data points, the reasonableness of numerical values, and the completeness of the time series. Missing data points are supplemented using interpolation methods to ensure the continuity of the trajectory. Numerical anomaly detection is based on statistical methods to identify and handle data points that exceed the normal range.

[0033] The matrix data is organized in row-major order, with temperature and pressure data matrices stored independently. Each matrix element corresponds to a monitoring value at a specific spatial location at a specific time. The number of rows in the matrix equals the total number of monitoring points, and the number of columns equals the total number of time samples, forming a well-structured data structure.

[0034] The trajectory extraction algorithm is implemented by scanning the matrix row by row, extracting all elements in the same row in column order to form a temporal evolution sequence of that spatial location. The extraction process preserves the temporal relationship of the data, ensuring that the trajectory reflects the true physical evolution process.

[0035] Through the above technical solution, this invention can effectively construct a data matrix reflecting the spatiotemporal distribution characteristics of temperature and pressure during the foaming process of polyurethane sandwich panels, accurately extract the evolution trajectory of each spatial location, provide a reliable data foundation for subsequent temperature and pressure coordinated control, improve the control accuracy of the foaming process and the stability of product quality, and reduce energy consumption and raw material consumption during the production process.

[0036] Step 103: Calculate the difference in evolution rate and the difference in inflection point time between the temperature evolution trajectory and the pressure evolution trajectory, and identify the spatial location of the imbalance and the corresponding spatiotemporal deviation.

[0037] In some embodiments of the present invention, step 103 may specifically include the following sub-steps: Sub-step 1031: Identify the transition boundary between the temperature rise segment and the temperature fall segment in the temperature evolution trajectory at each spatial location as the temperature inflection point time; identify the transition boundary between the pressure rise segment and the pressure fall segment in the pressure evolution trajectory as the pressure inflection point time; calculate the temporal misalignment between the temperature inflection point time and the pressure inflection point time at the same spatial location as the difference in evolution inflection point time. Sub-step 1032: Determine the time window between the temperature inflection point and the pressure inflection point based on the difference in the inflection point time. Calculate the difference in the change amplitude between the temperature evolution trajectory and the pressure evolution trajectory within the time window as the difference in evolution rate. Sub-step 1033 identifies spatial locations where both the difference in the inflection point time and the difference in the evolution rate exceed the preset imbalance judgment conditions as imbalance spatial locations, and calculates the comprehensive quantitative value of the difference in the inflection point time and the difference in the evolution rate of the imbalance spatial location as the corresponding spatiotemporal deviation.

[0038] Inflection point identification of temperature evolution trajectories is based on the transformation analysis of temperature change trends. The temperature evolution trajectory is stored as time-series data, recording temperature measurements at continuous time points at each spatial location. The inflection point identification process performs point-by-point differencing on the temperature series, calculates the temperature change between adjacent time points, and determines candidate inflection point locations by analyzing the transformation of the sign of the change.

[0039] The transition boundary between the temperature rise and temperature fall phases is identified using a rate of change sign monitoring method. A negative value appears after three consecutive positive rate of change at three time points, marking the transition boundary from the temperature rise phase to the fall phase. Conversely, a positive value appears after three consecutive negative rate of change at three time points, marking the transition boundary from the temperature fall phase to the rise phase. The rate of change threshold is set to 0.08℃ / s; changes below this threshold are considered a steady-state temperature condition and are not included in the inflection point determination.

[0040] The inflection point confirmation mechanism requires that the temperature change trends of the five sampling points before and after the inflection point remain consistent. The confirmation process verifies whether the direction of temperature change at the five sampling points before the inflection point is opposite to that at the five sampling points after the inflection point, and also verifies whether the magnitude of the change exceeds the minimum detectable temperature change of 0.2℃. Candidate locations that meet the confirmation conditions are officially marked as the temperature inflection point moments.

[0041] The inflection point identification process for the pressure evolution trajectory is the same as that for temperature inflection points, based on the sign conversion of the pressure change rate. The pressure change rate threshold is set to 0.015 MPa / s to ensure sensitivity and noise immunity in inflection point identification. The confirmation mechanism for pressure inflection points also requires consistency in the change trends of the five sampling points before and after the inflection point, with the minimum detectable pressure change set at 0.05 MPa.

[0042] The data preprocessing stage employs a 5-point moving average filter to reduce the interference of measurement noise on inflection point identification. The filtering process preserves the main trends in data variation while suppressing high-frequency noise components. The inflection point identification algorithm is executed on the filtered data, improving the stability and reliability of the identification results.

[0043] The time discrepancy between the temperature and pressure inflection points is calculated using the direct time difference method. The time discrepancy equals the pressure inflection point minus the temperature inflection point, measured in seconds. A positive value indicates that the pressure inflection point lags behind the temperature inflection point, while a negative value indicates that the pressure inflection point precedes the temperature inflection point. The absolute value of the time discrepancy quantifies the degree of temporal asynchrony between the two evolutionary processes.

[0044] The data structure for the differences in evolutionary inflection point times includes spatial location coordinates, temperature inflection point times, pressure inflection point times, and calculated temporal misalignment amounts. The data is organized in array form, supporting fast retrieval by spatial location and sorting by temporal misalignment amount. The difference data provides fundamental information for subsequent time window determination and misalignment assessment.

[0045] The time window is determined based on the calculated difference between the inflection points of the evolution, and the window range completely covers the time region between the temperature inflection point and the pressure inflection point. The window starts at the earlier of the two inflection points and ends at the later of the two inflection points. The length of the time window is equal to the absolute value of the time series misalignment, ensuring that the window includes the complete transition interval between the two evolution processes.

[0046] The calculation of the temperature evolution trajectory within the time window is achieved by extracting the temperature values ​​at the window boundaries. The temperature change amplitude is equal to the difference between the temperature value at the end of the window and the temperature value at the beginning of the window. The amplitude retains its sign information: a positive value indicates an overall temperature increase within the window, and a negative value indicates an overall temperature decrease. The absolute value of the amplitude reflects the intensity of the temperature change.

[0047] The calculation method for the magnitude of pressure evolution trajectory changes is the same as that for temperature changes, based on the difference between the initial and final pressure values ​​within a time window. The pressure change magnitude also retains its sign and absolute value information for subsequent rate difference calculations. The magnitude data is recorded along with the corresponding time window length, supporting standardized calculations of the rate of change.

[0048] The calculation of the evolution rate difference normalizes the magnitudes of temperature and pressure changes to their rates of change per unit time. The rate of temperature change equals the magnitude of temperature change divided by the length of the time window, and the rate of pressure change equals the magnitude of pressure change divided by the length of the time window. The evolution rate difference is defined as the difference between the absolute values ​​of the rates of temperature and pressure change.

[0049] The standardized formula for calculating the difference in variation is: Where ΔR represents the difference in evolution rate, |ΔT| represents the absolute value of the temperature change within the time window, |ΔP| represents the absolute value of the pressure change within the time window, and t w This indicates the length of the time window. The formula standardizes the magnitude of change to the rate of change per unit time, making the magnitudes of change across different time windows comparable.

[0050] The preset misalignment criteria include two standards: a threshold for the difference in evolution inflection point time and a threshold for the difference in evolution rate. The misalignment threshold for the difference in evolution inflection point time is set at 15s; when the absolute value of the temporal misalignment in spatial location exceeds this threshold, a temporal misalignment is determined to exist. The misalignment threshold for the difference in evolution rate is set at 0.4℃ / s; when the rate difference exceeds this threshold, a rate misalignment is determined to exist.

[0051] The identification of disordered spatial locations employs a dual-condition judgment mechanism, requiring both the difference in the inflection point time and the difference in the evolution rate to simultaneously exceed their respective disorder judgment criteria. A spatial location is only identified as disordered when the absolute value of the temporal misalignment is greater than 15 s and the rate difference is greater than 0.4 °C / s. This dual-condition mechanism avoids misjudgments caused by a single abnormal indicator, improving the accuracy of disorder identification.

[0052] The list of outlier locations records all anomalies identified through a dual-judgment process, including location coordinates, differences in evolution inflection points, and differences in evolution rates. This list data provides input for calculating the comprehensive quantification value and supports batch processing and priority sorting of outlier locations.

[0053] The comprehensive quantification process normalizes and weights two difference indicators at the location of the imbalance. Normalization employs a maximum-minimum standardization method within the set of imbalance locations, mapping the difference at the inflection point and the difference in evolution rate to numerical ranges of 0 to 1. The normalization parameters are dynamically determined based on the data distribution of the current set of imbalance locations.

[0054] The normalized value of the difference in inflection point moments is equal to the difference minus the minimum difference in inflection point moments in the set of imbalanced locations, divided by the difference between the maximum and minimum values. The normalization of the difference in evolution rate is performed using the same method to ensure that the two indicators are calculated together within a unified numerical range.

[0055] The comprehensive quantification formula for spatiotemporal deviation is: Q = 0.6 × Nt + 0.4 × Nr, where Q represents the spatiotemporal deviation, Nt represents the normalized difference in the evolution inflection point time, and Nr represents the normalized difference in the evolution rate. The weighting coefficients 0.6 and 0.4 correspond to the importance of the difference in inflection point time and rate difference in temperature-pressure coordinated regulation, respectively. The comprehensive quantification value is directly used as the spatiotemporal deviation corresponding to the spatial location of the misalignment.

[0056] The spatiotemporal deviation data output includes the coordinates of the misalignment's spatial location and the corresponding comprehensive quantification value, stored in a structured format for subsequent control. The spatiotemporal deviation value ranges from 0 to 1, with larger values ​​indicating more severe misalignment. The data supports sorting by deviation magnitude, providing a basis for priority control.

[0057] Through the above-mentioned technical solution, this invention can accurately identify the temporal and rate imbalances in temperature and pressure evolution during the foaming process of polyurethane sandwich panels, precisely locate the spatial position of the imbalance and quantify the degree of deviation, provide a reliable basis for imbalance diagnosis for coordinated temperature and pressure control, and improve the coordination of the foaming process and the consistency of product quality.

[0058] Step 104: Based on the distribution of the misalignment spatial location in the direction of board movement, trace the propagation path of the spatiotemporal deviation along the direction of board movement, calculate the cumulative effect of the spatiotemporal deviation on the propagation path, and determine the downstream spatial location range of the cumulative effect.

[0059] In some embodiments of the present invention, step 104 may specifically include the following sub-steps: Sub-step 1041: Arrange the misaligned spatial positions into a propagation sequence according to the distribution of the misaligned spatial positions in the material movement direction; calculate the transmission intensity of the spatiotemporal deviation between adjacent positions based on the spatial distance and spatiotemporal deviation in the propagation sequence; and construct the propagation path of the spatiotemporal deviation along the material movement direction based on the transmission intensity. Sub-step 1042: Process the misalignment spatial positions in the propagation sequence sequentially along the propagation path, attenuate the spatiotemporal deviation upstream of the current position according to the propagation intensity, and superimpose the attenuated upstream spatiotemporal deviation with the spatiotemporal deviation of the current position to obtain the cumulative spatiotemporal deviation of the current position. Use the cumulative spatiotemporal deviation of each misalignment spatial position in the propagation sequence as the cumulative effect of the spatiotemporal deviation on the propagation path. Sub-step 1043: Identify the peak position from the cumulative effect of the spatiotemporal deviation on the propagation path, track the decay process of the cumulative effect from the peak position along the material movement direction until the cumulative effect decays to dissipation, and determine the spatial range between the peak position and the dissipation position as the downstream spatial position range of the cumulative effect.

[0060] The construction of the spatiotemporal deviation propagation path is based on the distribution characteristics of the misalignment spatial locations along the material movement direction. The misalignment spatial locations are sorted according to their actual coordinates on the production line, forming an ordered sequence along the material movement direction. The sorting process arranges the coordinate values ​​of each misalignment location from smallest to largest, constituting a propagation sequence that reflects the potential propagation order of the spatiotemporal deviation along the production line.

[0061] The transmission intensity is calculated based on the spatial distance between adjacent misalignment locations and the corresponding spatiotemporal deviation. The spatial distance is obtained through the coordinate difference between adjacent locations, expressed in meters as the physical distance between two misalignment locations. The transmission intensity comprehensively considers the spatial attenuation effect and the initial intensity of the spatiotemporal deviation, and uses an inverse distance-to-weight ratio to model the attenuation characteristics during the transmission process.

[0062] The formula for calculating the transmission strength is: Where I represents the transmission intensity, and D o Let d represent the spatiotemporal deviation of the upstream location, d represent the spatial distance between adjacent locations, and k represent the attenuation coefficient, with a value of 1.0m. This formula shows that the transmission intensity is directly proportional to the spatiotemporal deviation and inversely proportional to the spatial distance, which conforms to the basic laws of physical propagation.

[0063] A propagation path is constructed by connecting the various misalignment spatial locations in the propagation sequence, forming a continuous path along the material movement direction. Each node in the path corresponds to a misalignment spatial location, and the connecting edges between nodes represent the propagation direction and transmission intensity of the spatiotemporal deviation. The path construction process maintains unidirectionality, ensuring that the propagation direction is consistent with the material movement direction.

[0064] The calculation of cumulative spatiotemporal deviation is performed position by position along the propagation path, starting from the beginning of the propagation sequence. For each position in the propagation sequence, the contribution of all upstream positions to the current position is calculated. The upstream contribution is obtained by attenuating the spatiotemporal deviation of each upstream position; the degree of attenuation is determined by the propagation strength.

[0065] The attenuation process employs an exponential decay model, and the formula for calculating the upstream spatiotemporal deviation after attenuation is as follows: , where D d D represents the upstream spatiotemporal deviation after decay. u The original spatiotemporal deviation of the upstream location is represented by α, which is the attenuation constant with a value of 0.1 / m. t This represents the cumulative distance from the upstream location to the current location. This formula ensures that the upstream influence gradually weakens as the propagation distance increases.

[0066] The cumulative spatiotemporal offset at the current location is obtained by adding all attenuated upstream contributions to the original spatiotemporal offset at the current location. The accumulation process is performed sequentially according to the propagation sequence, ensuring that each location includes the cumulative effects of all its upstream locations. The cumulative calculation results reflect the superposition effect of the spatiotemporal offset during propagation.

[0067] Peak positions are identified by traversing the cumulative spatiotemporal deviations at various locations in the propagation sequence. A peak position corresponds to the spatial location where the cumulative spatiotemporal deviation reaches a local maximum, typically situated within a region where multiple offset sources interact. Peak identification employs a local extremum detection method, requiring that the cumulative deviation at the peak point be greater than the corresponding values ​​at its adjacent locations.

[0068] The tracking of the cumulative effect decay process continues from the peak position along the material movement direction, monitoring the changing trend of the cumulative spatiotemporal deviation. During the decay process, the cumulative deviation gradually decreases, and when the cumulative deviation drops to 10% of the peak value, the cumulative effect is considered to have essentially dissipated. The dissipation point is the termination point of the cumulative effect's influence range.

[0069] The downstream spatial range is determined based on the coordinates of the peak and dissipation locations. The initial boundary of the spatial range is the coordinates of the peak location, and the final boundary is the coordinates of the dissipation location. The length of the range is equal to the difference between the coordinates of the two boundaries. All spatial locations within this range are significantly affected by the cumulative effect and require focused control.

[0070] The validity of the propagation path is verified by checking the continuity of the path and the reasonableness of the transmission intensity. Path continuity requires that the distance between adjacent positions in the propagation sequence does not exceed the preset maximum propagation distance, which is set to 2.0m. Reasonableness of transmission intensity requires that all transmission intensity values ​​are positive and do not exceed the upper limit of 1.0.

[0071] Boundary condition handling considers special cases at the beginning and end positions of the propagation sequence. At the beginning position, there is no upstream contribution, and its cumulative spatiotemporal deviation equals the original spatiotemporal deviation. At the end position, the cumulative effect may extend to the production line boundary; in this case, the end of the production line is used as the boundary constraint for the dissipation location.

[0072] The data update mechanism ensures the real-time calculation of propagation paths. When a new spatial location of misalignment is detected, the propagation sequence and propagation path are reconstructed. The update process maintains the continuity of the calculation results, avoiding the impact of frequent changes on control decisions. The stability of the propagation path is improved through moving average processing, with the average window length set to 5 calculation cycles.

[0073] Through the above-mentioned technical solution, this invention can accurately track the propagation law of spatiotemporal deviation in the foaming process of polyurethane sandwich panels, accurately calculate the spatial distribution and influence range of the cumulative effect, provide a scientific basis for preventive control in downstream areas, effectively avoid the spread and amplification of imbalance phenomena, and improve the stability of the entire foaming process and the uniformity of product quality.

[0074] In sub-step 1041, calculating the transmission strength of the spatiotemporal deviation between adjacent locations based on the spatial spacing and spatiotemporal deviation between adjacent misalignment locations in the propagation sequence further includes: Obtain the spatial distance between adjacent misalignment locations in the propagation sequence, calculate the ratio of the spatial distance to the preset attenuation reference distance, and determine the spatial attenuation coefficient based on the ratio; The spatiotemporal deviation of the adjacent misalignment spatial position pair in the propagation sequence located upstream of the material movement direction is obtained. The spatiotemporal deviation is then used to perform attenuation calculation with the spatial attenuation coefficient to obtain the attenuation transmission amount based on the spatial spacing. Extract the temperature evolution trajectory and pressure evolution trajectory of adjacent misalignment spatial location pairs in the propagation sequence, calculate the gradient difference of temperature evolution trajectory and pressure evolution trajectory between adjacent misalignment spatial location pairs, and calculate the temperature-pressure coupling enhancement factor based on the gradient difference of temperature evolution trajectory and pressure evolution trajectory. Multiplying the attenuation transfer amount based on spatial spacing with the temperature-pressure coupling enhancement factor yields the transfer intensity of spatiotemporal deviation between adjacent locations.

[0075] Spatial spacing is obtained by reading the coordinate data of adjacent misalignment spatial positions in the propagation sequence. The absolute value of the difference between the coordinates of adjacent positions is calculated as the spatial spacing. The spatial spacing is measured precisely in millimeters to ensure the accuracy of subsequent attenuation calculations.

[0076] The preset attenuation reference distance is determined based on the thermal conductivity and pressure transmission characteristics of polyurethane foam material and is set to 500 mm. This reference distance represents the standard distance at which the transmission capacity remains significant despite spatiotemporal deviations; beyond this distance, the transmission effect will show significant attenuation. The ratio of the spatial spacing to the preset attenuation reference distance is obtained through direct division, and the ratio reflects the degree of deviation of the actual spacing from the reference distance.

[0077] The spatial attenuation coefficient is determined using a piecewise function based on the ratio. When the ratio is less than 0.5, the spatial attenuation coefficient is set to 0.9, indicating a strong transmission effect; when the ratio is between 0.5 and 1.0, the attenuation coefficient is set to 0.7, indicating a moderate transmission effect; when the ratio is between 1.0 and 2.0, the attenuation coefficient is set to 0.4, indicating a weak transmission effect; and when the ratio exceeds 2.0, the attenuation coefficient is set to 0.1, indicating a very weak transmission effect.

[0078] The spatiotemporal deviation of the upstream position is obtained by accessing the spatiotemporal deviation data of adjacent position pairs in the propagation sequence. The position upstream in the material movement direction of the adjacent position pair corresponds to a smaller coordinate value, and its spatiotemporal deviation value is directly extracted from the aforementioned calculation results. The spatiotemporal deviation is expressed as a dimensionless value, typically ranging from 0.1 to 5.0.

[0079] The attenuation transfer based on spatial spacing is obtained by multiplying the spatiotemporal deviation at the upstream location by the corresponding spatial attenuation coefficient. The attenuation calculation uses simple multiplication; the value of the attenuation transfer is less than or equal to the original spatiotemporal deviation, and the degree of attenuation depends on the magnitude of the spatial attenuation coefficient. The attenuation transfer maintains the same dimensional characteristics as the original spatiotemporal deviation.

[0080] The gradient of the temperature evolution trajectory is calculated based on temperature evolution data from adjacent misaligned spatial locations. The gradient is obtained by calculating the rate of temperature change using the first-order difference method of the temperature data sequence, dividing the temperature change between adjacent time points by the time interval. The gradient calculation results are expressed in °C / s, with positive values ​​indicating an upward temperature trend and negative values ​​indicating a downward temperature trend.

[0081] The calculation method for the pressure evolution trajectory gradient is similar to that for the temperature gradient, based on first-order difference processing of the pressure evolution data. The pressure gradient is expressed in MPa / s, reflecting the rate of pressure change. The gradient calculation process uses the same time interval setting to ensure that the time base of the temperature gradient and the pressure gradient are consistent.

[0082] The difference in temperature evolution trajectory gradients between adjacent misalignment pairs is obtained by calculating the difference in temperature gradients between the two locations. The difference is calculated by subtracting the gradient from the upstream gradient, and the sign of the result reflects the directionality of the gradient change. The absolute value of the temperature gradient difference indicates the degree of difference in temperature change trends between adjacent locations.

[0083] The pressure evolution trajectory gradient difference is calculated using the same method as the temperature gradient difference, obtained by subtracting the upstream pressure gradient from the downstream pressure gradient. The pressure gradient difference is also presented as an absolute value in subsequent calculations to eliminate directional influences and focus on quantifying the degree of difference.

[0084] The temperature-pressure coupling enhancement factor is calculated based on the combined effect of the temperature gradient difference and the pressure gradient difference. The calculation formula is: , of which F c ΔG represents the temperature-pressure coupling enhancement factor, A represents the coupling coefficient with a value of 0.2, and ΔG T ΔG represents the gradient difference of the temperature evolution trajectory. P This represents the gradient difference of the pressure evolution trajectory. The formula uses Euclidean distance to combine the effects of the two gradient differences, and the coupling enhancement factor typically ranges from 1.0 to 2.5.

[0085] The final calculation of the transmission strength is achieved by multiplying the attenuation transmission amount based on the spatial spacing with the temperature-pressure coupling enhancement factor. The transmission strength comprehensively reflects the influence of two key factors, spatial attenuation and temperature-pressure coupling, on the transmission process.

[0086] Numerical verification of the transmission strength is achieved by setting reasonableness check conditions. The value of the transmission strength should be positive and not exceed twice the original spatiotemporal deviation of the upstream location. Calculation results exceeding this range require re-verification of the accuracy of the input data. The verification process ensures the physical reasonableness of the transmission strength calculation results.

[0087] Boundary condition handling considers special cases at the beginning and end positions of the propagation sequence. The propagation strength of the starting position, which has no upstream neighbors, is set to zero. The propagation strength at the end position only affects the outer region of the sequence and does not participate in the cumulative calculation within the sequence. Boundary handling ensures the integrity and continuity of the propagation strength calculation.

[0088] Precision control is achieved by setting numerical rounding rules. The calculation results for the transmitted intensity are retained to three significant figures to avoid numerical instability caused by excessive precision. The rounding process adopts standard rounding rules to ensure the consistency and repeatability of the calculation results.

[0089] Through the above technical solution, this invention can accurately calculate the transmission intensity of spatiotemporal deviation during the foaming process of polyurethane sandwich panels. By comprehensively considering the dual effects of spatial attenuation and temperature-pressure coupling, it improves the accuracy and physical rationality of the transmission intensity calculation, and provides reliable basic data support for the construction of the spatiotemporal deviation propagation path and the prediction of the cumulative effect.

[0090] Step 105: For each spatial location within the downstream spatial location range, calculate the temperature compensation amount and pressure compensation amount required to offset the cumulative effect, and determine the time interval between the application of the temperature compensation amount and the application of the pressure compensation amount based on the response time of the temperature compensation amount and the response time of the pressure compensation amount.

[0091] In some embodiments of the present invention, step 105 may specifically include the following sub-steps: Sub-step 1051: Obtain the cumulative spatiotemporal deviation corresponding to each spatial location within the downstream spatial location range, and decompose the cumulative spatiotemporal deviation into temperature dimension deviation component and pressure dimension deviation component. Sub-step 1052: Calculate the temperature compensation required to offset the cumulative effect based on the rate of change of the temperature dimension deviation component and the temperature evolution trajectory; calculate the pressure compensation required to offset the cumulative effect based on the rate of change of the pressure dimension deviation component and the pressure evolution trajectory. Sub-step 1053: Calculate the time required to offset the temperature dimension deviation component after the temperature compensation is applied as the response time of the temperature compensation; calculate the time required to offset the pressure dimension deviation component after the pressure compensation is applied as the response time of the pressure compensation. Sub-step 1054: Calculate the response time difference between the response time of the temperature compensation and the response time of the pressure compensation, and calculate the spatiotemporal propagation offset based on the response time difference and the material movement speed. Sub-step 1055: Add the response time difference to the time advance corresponding to the spatiotemporal propagation offset to obtain the time interval between the application of the temperature compensation and the application of the pressure compensation.

[0092] The cumulative spatiotemporal deviation of each spatial location within the downstream spatial range is obtained by accessing the cumulative effect data calculated above. The cumulative spatiotemporal deviation data is indexed according to spatial coordinates, with each spatial location corresponding to a cumulative spatiotemporal deviation value. The data acquisition process traverses all coordinate points within the downstream spatial range, extracts the corresponding cumulative spatiotemporal deviation values, and stores them as an ordered array.

[0093] The cumulative spatiotemporal deviation is decomposed into temperature and pressure deviation components based on preset decomposition weighting coefficients. The temperature deviation component is obtained by multiplying the cumulative spatiotemporal deviation by a temperature weighting coefficient, which is set to 0.6 based on the influence of temperature during polyurethane foaming. The pressure deviation component is obtained by multiplying the cumulative spatiotemporal deviation by a pressure weighting coefficient, which is set to 0.4. The sum of the two weighting coefficients equals 1.0 to ensure the integrity of the decomposition process.

[0094] The correlation analysis between the temperature dimensional deviation component and the rate of change of the temperature evolution trajectory is achieved by calculating the instantaneous rate of change of the temperature evolution trajectory. The rate of change of the temperature evolution trajectory is obtained by numerically differentiating the temperature data sequence, and the forward differencing method is used to calculate the temperature change between adjacent time points divided by the time interval. The rate of change is expressed in °C / s, with positive values ​​indicating a temperature increase and negative values ​​indicating a temperature decrease.

[0095] The temperature compensation amount is calculated based on the magnitude of the temperature deviation component and the response characteristics of the rate of change of the temperature evolution trajectory. The temperature compensation amount employs a reverse compensation principle, that is, it counteracts the deviation effect by applying a temperature adjustment amount in the opposite direction to the deviation component. The formula for calculating the temperature compensation amount is: , where C T D represents the temperature compensation amount. T-dim R represents the temperature dimension deviation component. T K represents the rate of change of the temperature evolution trajectory. T This represents the temperature response coefficient, with a value of 1.2. This formula ensures that the temperature compensation is directly proportional to the deviation component and inversely proportional to the rate of change.

[0096] The handling of the pressure dimension deviation component and the rate of change of the pressure evolution trajectory is similar to that of the temperature dimension. The rate of change of the pressure evolution trajectory is obtained by numerically differentiating the pressure data sequence, and the result is expressed in MPa / s. The sign of the pressure change rate reflects the trend of pressure increase or decrease, and the magnitude of the value reflects the severity of the change.

[0097] The pressure compensation is calculated using a reverse compensation mechanism similar to that used for temperature compensation. The formula for calculating the pressure compensation is: , where C P D represents the pressure compensation amount. P-dim R represents the deviation component of the pressure dimension. P K represents the rate of change of the pressure evolution trajectory. P This represents the pressure response coefficient, with a value of 0.8. The pressure compensation value typically ranges from 0.01 MPa to 0.5 MPa.

[0098] The temperature compensation response time is calculated based on the time required for the system to reach a steady state after the temperature compensation is applied. The response time calculation considers the thermal conductivity characteristics during the polyurethane foaming process and the response delay of the temperature control equipment. The temperature response time is obtained by dividing the temperature compensation by the temperature control rate, which is set to 5.0℃ / s. The response time is expressed in seconds.

[0099] The calculation method for pressure compensation response time is similar to that for temperature response time, based on the pressure compensation amount and the response characteristics of the pressure regulating device. The pressure regulation rate is set to 0.1 MPa / s, and the pressure response time is obtained by dividing the pressure compensation amount by the pressure regulation rate. The pressure response time is typically shorter than the temperature response time, reflecting the rapid response characteristics of the pressure regulation.

[0100] The response time difference is obtained by calculating the difference between the response time of the temperature compensation and the response time of the pressure compensation. The difference is calculated by subtracting the pressure response time from the temperature response time, and the sign of the result reflects the relative relationship between the response times of the two compensations. A positive difference indicates a longer temperature response time, while a negative difference indicates a longer pressure response time.

[0101] The calculation of spatiotemporal propagation offset is based on the product of the response time difference and the material movement speed. The material movement speed is obtained by monitoring the movement speed of the polyurethane sandwich panels on the production line, and the speed value is expressed in m / s. The spatiotemporal propagation offset is equal to the response time difference multiplied by the material movement speed, and the result is expressed as the spatial offset distance in meters.

[0102] The time lead corresponding to the spatiotemporal propagation offset is obtained by dividing the spatial offset distance by the material movement speed. This calculation is actually equal to the response time difference itself. The time lead reflects the length of time that temperature compensation needs to be applied in advance to compensate for different response times, ensuring the time synchronization of temperature and pressure compensation effects.

[0103] The time interval between the application of temperature compensation and pressure compensation is obtained by adding the response time difference to the time advance. Since the time advance equals the response time difference, the time interval is effectively twice the response time difference. This time interval ensures that the temperature compensation has sufficient time to take effect and achieve a synergistic effect with the pressure compensation.

[0104] The validity of the time interval is verified by checking its reasonable range. The time interval should be a positive value and not exceed the upper limit of 10 seconds. Calculations exceeding this range require re-verification of the accuracy of the input parameters. The verification process ensures the practicality and operability of the time interval calculation results.

[0105] Limits to the compensation values ​​ensure that temperature and pressure compensation amounts do not exceed the equipment's adjustment capabilities. The upper limit for temperature compensation is set at 50°C, and the upper limit for pressure compensation is set at 1.0 MPa. Compensation amounts exceeding these limits need to be applied in segments or the calculation parameters need to be adjusted to avoid equipment overload or adjustment failure.

[0106] The dynamic adjustment mechanism of the time interval is updated based on real-time changes in material movement speed. When the material movement speed changes significantly, the spatiotemporal propagation offset and time advance are recalculated, and the time interval value is updated. Dynamic adjustment ensures that the time synchronization of temperature and pressure coordinated control adapts to changes in the production process.

[0107] Through the above technical solution, this invention can accurately calculate the temperature and pressure compensation required to offset the cumulative effect during the foaming process of polyurethane sandwich panels, reasonably determine the application time interval of the two compensation amounts, achieve precise coordination of temperature and pressure control, effectively offset the cumulative effect of spatiotemporal deviation, and ensure the stability of the foaming process and the consistency of product quality.

[0108] Step 106: Based on the temperature compensation amount, pressure compensation amount, and time interval, output compensation and control commands to the temperature control equipment and pressure control equipment corresponding to the downstream spatial location range.

[0109] Temperature control equipment includes, but is not limited to, zoned heating plates and cooling air systems; pressure control equipment includes, but is not limited to, pressure rollers and laminator pressure regulating devices.

[0110] In some embodiments of the present invention, step 106 may specifically include the following sub-steps: Sub-step 1061: Based on the spatial mapping relationship between each spatial location within the downstream spatial location range and the temperature control equipment and pressure control equipment, determine the temperature control equipment and pressure control equipment corresponding to the downstream spatial location range. Sub-step 1062: For the temperature control equipment corresponding to the downstream spatial location range, calculate the application time of the temperature compensation amount based on the temperature compensation amount and the time interval, and calculate the temperature regulation range based on the control response characteristics of the temperature control equipment and the temperature compensation amount. Sub-step 1063: For the pressure control equipment corresponding to the downstream spatial location range, calculate the application time of the pressure compensation amount based on the pressure compensation amount and the time interval, and calculate the pressure regulation amplitude based on the control response characteristics of the pressure control equipment and the pressure compensation amount. Sub-step 1064: Based on the application time of the temperature compensation amount and the temperature control amplitude, output the temperature compensation control command to the temperature control device corresponding to the downstream spatial location range. Sub-step 1065: Based on the application time of the pressure compensation amount and the pressure regulation amplitude, output pressure compensation regulation command to the pressure control equipment corresponding to the downstream spatial location range.

[0111] The spatial mapping relationship between downstream spatial locations and temperature and pressure control devices is established based on a preset device layout configuration table. The spatial mapping relationship is stored in coordinate correspondence, with each spatial location coordinate corresponding to the identifier of one or more control devices. The mapping relationship data includes the horizontal and vertical coordinates of the spatial location, the corresponding temperature control device number, and the pressure control device number.

[0112] The process of determining temperature control equipment involves querying a spatial mapping table, retrieving the corresponding temperature control equipment number based on the coordinates of each coordinate point within the downstream spatial location range. When multiple spatial locations correspond to the same temperature control equipment, that equipment needs to comprehensively handle the temperature compensation requirements of multiple locations. The equipment determination results form a list of temperature control equipment, including the equipment number, control range, and corresponding spatial location list.

[0113] The method for identifying pressure control equipment is similar to that for temperature control equipment, involving querying the corresponding pressure control equipment number by traversing the coordinates of coordinate points within the downstream spatial location range. The pressure control equipment list records the equipment's identification information, control area range, and associated spatial coordinates. This equipment list provides an accurate basis for generating subsequent compensation commands.

[0114] The calculation of the application time of temperature compensation is based on the current time point and the time interval calculated above. The application time equals the current time point plus the time interval, ensuring that the temperature compensation is applied at the appropriate time to achieve a synergistic effect with the pressure compensation. The time calculation is expressed as a timestamp in seconds, providing a precise time control reference.

[0115] The control response characteristics of temperature control equipment include parameters such as adjustment accuracy, response delay, and adjustment range. Adjustment accuracy reflects the minimum temperature adjustment increment the equipment can achieve, typically set to 0.1℃. Response delay represents the time difference between receiving a command and starting to execute the adjustment, generally 1 to 3 seconds. The adjustment range defines the upper and lower limits of the temperature adjustment amplitude that the equipment can achieve.

[0116] The calculation of the temperature control amplitude takes into account the matching relationship between the temperature compensation amount and the equipment control response characteristics. The formula for calculating the control amplitude is: A T =C T ×G T ×η T , where A T Indicates the temperature control range, C T G represents the temperature compensation amount. T This represents the temperature control gain coefficient, with a value of 1.1, η. T This represents the temperature control efficiency coefficient, with a value of 0.9. This formula ensures that the control amplitude can effectively achieve the compensation target, while also taking into account the influence of the equipment's response characteristics.

[0117] The calculation of the pressure compensation application time is based on the current time point and does not require additional time offset because the pressure compensation amount serves as a reference for time synchronization. The application time of the pressure compensation amount is equal to the current time point, providing a time reference point for the coordinated control of temperature compensation amount and pressure compensation amount.

[0118] The control response characteristics of pressure control equipment include pressure regulation accuracy, response delay, and regulation range. The pressure regulation accuracy is set to 0.01 MPa, the response delay is typically 0.5 to 2 seconds, and the regulation range is determined according to the equipment specifications. These parameters directly affect the calculation of the pressure control amplitude and the generation of commands.

[0119] The formula for calculating the pressure control range is: A P =C P ×G P ×η P A P Indicates the pressure regulation range, C P G represents the pressure compensation amount. P This represents the pressure control gain coefficient, with a value of 1.05, η. P This represents the pressure control efficiency coefficient, with a value of 0.95. The calculated pressure regulation range must meet the adjustment range limitations of the pressure control equipment.

[0120] The generation of temperature compensation control commands includes information such as command identifier, target device number, application time, control range, and execution mode. The command identifier is a unique identifier generated by combining a timestamp and the device number. The execution mode is set to immediate execution or timed execution, determined based on the relationship between the application time and the current time.

[0121] The temperature compensation control command uses a structured command format, including a command header, control parameters, and verification information. The command header records the command type, priority, and timestamp. The control parameters include the target temperature control range, execution duration, and control accuracy requirements. The verification information ensures the reliability of command transmission.

[0122] The generation method for pressure compensation control commands is similar to that for temperature compensation control commands, employing the same command format and data structure. Pressure compensation control commands contain key information such as the pressure control amplitude, application time, and target equipment number. The command generation process ensures that the pressure compensation amount is applied to the corresponding control equipment at the accurate time.

[0123] The communication protocol for command output adopts a standard industrial control communication interface, supporting real-time data transmission and command confirmation mechanisms. Temperature compensation and control commands are sent to the corresponding temperature control equipment through a dedicated temperature control channel, ensuring timely transmission and accurate execution of commands.

[0124] Pressure compensation and control commands are output to the corresponding pressure control equipment through an independent pressure control channel. The command output process includes command sending, reception confirmation, and execution status feedback to ensure reliable command execution and real-time monitoring.

[0125] Priority management of command execution ensures that compensation and control commands are executed first, avoiding conflicts with other control commands. Temperature compensation and control commands and pressure compensation and control commands have the same high priority, guaranteeing the timeliness and effectiveness of coordinated temperature and pressure control.

[0126] The command execution status monitoring mechanism tracks the control equipment's execution of compensation and regulation commands in real time. Monitoring information includes feedback data such as command reception status, execution progress, and completion confirmation. Execution status information provides data support for evaluating the regulation effect and subsequent optimization.

[0127] The exception handling mechanism addresses situations such as command transmission failure, abnormal device response, or execution timeout. When an exception is detected, it automatically triggers the sending of backup commands or switches to backup control equipment to ensure the continuity and stability of temperature and pressure coordinated regulation.

[0128] The command recording and tracing function saves detailed information on all compensation and control commands, including command content, sending time, execution results, and equipment feedback. This recorded information is used for auditing the control process, analyzing its effects, and optimizing parameters, thereby improving the continuous improvement capabilities of the temperature and pressure coordinated control method.

[0129] Through the above technical solution, this invention can accurately determine the control equipment corresponding to the downstream spatial location range, accurately calculate the application time and control amplitude of the compensation amount, reliably output temperature and pressure compensation control commands, realize precise temperature and pressure coordinated control in the polyurethane sandwich panel foaming process, effectively offset the cumulative effect of spatiotemporal deviation, and ensure the stability of the foaming process and the consistency of product quality.

[0130] like Figure 2 As shown, Figure 2 This is a schematic diagram of a temperature and pressure coordinated control system for the continuous foaming process of polyurethane sandwich panels provided in an embodiment of the present invention. The system includes: The data acquisition module 201 is used to collect temperature monitoring data and pressure monitoring data at multiple spatial locations distributed along the material movement direction; The spatiotemporal modeling module 202 is used to construct a spatiotemporal distribution matrix from temperature monitoring data and pressure monitoring data, and extract the temperature evolution trajectory and pressure evolution trajectory at each spatial location. The imbalance identification module 203 is used to calculate the difference in evolution rate and the difference in evolution inflection point time between the temperature evolution trajectory and the pressure evolution trajectory, and to identify the spatial location of the imbalance and the corresponding spatiotemporal deviation. The propagation analysis module 204 is used to track the propagation path of the spatiotemporal deviation along the direction of the board movement based on the distribution of the misalignment spatial position in the direction of board movement, calculate the cumulative effect of the spatiotemporal deviation on the propagation path, and determine the downstream spatial position range of the cumulative effect. The compensation calculation module 205 is used to calculate the temperature compensation amount and pressure compensation amount required to offset the cumulative effect for each spatial location within the downstream spatial location range, and to determine the time interval between the application of the temperature compensation amount and the application of the pressure compensation amount based on the response time of the temperature compensation amount and the response time of the pressure compensation amount. The control output module 206 is used to output compensation control commands to the temperature control equipment and pressure control equipment corresponding to the downstream spatial location range based on the temperature compensation amount, pressure compensation amount and time interval.

[0131] One technical solution provided in this embodiment of the invention is an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps in any of the aforementioned methods.

[0132] One technical solution provided in this embodiment of the invention is a computer-readable storage medium storing a computer program, wherein the processor executes the computer program to implement the steps in any of the aforementioned methods.

[0133] The specific embodiments described above are preferred embodiments of the present invention and are not intended to limit the specific scope of the present invention. The scope of the present invention includes, but is not limited to, these specific embodiments. All equivalent changes made in accordance with the shape and structure of the present invention are within the protection scope of the present invention.

Claims

1. A method for coordinated temperature and pressure control during the continuous foaming process of polyurethane sandwich panels, characterized in that, Includes the following steps: Temperature and pressure monitoring data are collected from multiple spatial locations distributed along the material movement direction; A spatiotemporal distribution matrix was constructed using temperature monitoring data and pressure monitoring data, and the temperature evolution trajectory and pressure evolution trajectory at each spatial location were extracted. Calculate the difference in evolution rate and the difference in inflection point between the temperature evolution trajectory and the pressure evolution trajectory to identify the spatial location of the imbalance and the corresponding spatiotemporal deviation. Based on the distribution of the misalignment spatial location along the direction of plate movement, the propagation path of the spatiotemporal deviation is traced along the direction of plate movement. The cumulative effect of the spatiotemporal deviation along the propagation path is calculated, and the downstream spatial location range of the cumulative effect is determined. For each spatial location within the downstream spatial location range, calculate the temperature compensation and pressure compensation required to offset the cumulative effect, and determine the time interval between the application of temperature compensation and pressure compensation based on the response time of temperature compensation and pressure compensation. Based on the temperature compensation amount, pressure compensation amount, and time interval, compensation and control commands are output to the temperature control equipment and pressure control equipment corresponding to the downstream spatial location range.

2. The method according to claim 1, characterized in that, A spatiotemporal distribution matrix was constructed using temperature and pressure monitoring data, and the temperature and pressure evolution trajectories at each spatial location were extracted, including: The spatial coordinates of each location in the material movement direction are used as spatial dimension indexes, and the collection time of temperature and pressure monitoring data is used as time dimension indexes. According to the correspondence between location coordinates and collection time, temperature and pressure monitoring data are filled into the corresponding index positions to construct a spatiotemporal distribution matrix. Temperature monitoring data at different collection times corresponding to the same spatial location are extracted from the spatiotemporal distribution matrix and arranged in chronological order of collection times to form the temperature evolution trajectory of each spatial location. Pressure monitoring data at different collection times corresponding to the same spatial location are extracted from the spatiotemporal distribution matrix and arranged in chronological order of collection times to form the pressure evolution trajectory of each spatial location.

3. The method according to claim 1, characterized in that, Calculating the difference in evolution rate and inflection point time between the temperature evolution trajectory and the pressure evolution trajectory, and identifying the spatial location of the misalignment and the corresponding spatiotemporal deviation, includes: The transition boundary between the temperature rise and temperature fall segments in the temperature evolution trajectory at each spatial location is identified as the temperature inflection point. The transition boundary between the pressure rise and pressure fall segments in the pressure evolution trajectory is identified as the pressure inflection point. The temporal misalignment between the temperature inflection point and the pressure inflection point at the same spatial location is calculated as the difference in the evolution inflection point. Based on the difference in the inflection point of evolution, the time window between the temperature inflection point and the pressure inflection point is determined, and the difference in the change amplitude of the temperature evolution trajectory and the pressure evolution trajectory within the time window is calculated as the difference in evolution rate. Spatial locations where both the difference in the inflection point of evolution and the difference in the rate of evolution exceed the preset misalignment criteria are identified as misaligned spatial locations. The comprehensive quantitative value of the difference in the inflection point of evolution and the difference in the rate of evolution at the misaligned spatial location is calculated as the corresponding spatiotemporal deviation.

4. The method according to claim 1, characterized in that, Based on the distribution of the misalignment spatial location along the board's movement direction, the propagation path of the spatiotemporal deviation is traced along the board's movement direction. The cumulative effect of the spatiotemporal deviation along the propagation path is calculated, and the downstream spatial location range of the cumulative effect is determined, including: Based on the distribution of the misalignment spatial locations in the material movement direction, the misalignment spatial locations are arranged into a propagation sequence. Based on the spatial distance and spatiotemporal deviation between adjacent misalignment spatial locations in the propagation sequence, the transmission intensity of the spatiotemporal deviation between adjacent locations is calculated. Based on the transmission intensity, the propagation path of the spatiotemporal deviation along the material movement direction is constructed. The spatial locations of the misalignment in the propagation sequence are processed sequentially along the propagation path. The spatiotemporal deviation upstream of the current location is attenuated according to the propagation intensity. The attenuated upstream spatiotemporal deviation is superimposed with the spatiotemporal deviation at the current location to obtain the cumulative spatiotemporal deviation at the current location. The cumulative spatiotemporal deviation of each misalignment location in the propagation sequence is taken as the cumulative effect of the spatiotemporal deviation on the propagation path. The peak position is identified from the cumulative effect of the spatiotemporal deviation along the propagation path. The decay process of the cumulative effect is traced from the peak position along the material movement direction until the cumulative effect decays to dissipation. The spatial range between the peak position and the dissipation position is determined as the downstream spatial range of the cumulative effect.

5. The method according to claim 4, characterized in that, The calculation of the propagation strength of spatiotemporal deviation between adjacent locations based on the spatial spacing and spatiotemporal deviation between adjacent misalignment locations in the propagation sequence includes: Obtain the spatial distance between adjacent misalignment locations in the propagation sequence, calculate the ratio of the spatial distance to the preset attenuation reference distance, and determine the spatial attenuation coefficient based on the ratio; The spatiotemporal deviation of the adjacent misalignment spatial position pair in the propagation sequence located upstream of the material movement direction is obtained. The spatiotemporal deviation is then used to perform attenuation calculation with the spatial attenuation coefficient to obtain the attenuation transmission amount based on the spatial spacing. Extract the temperature evolution trajectory and pressure evolution trajectory of adjacent misalignment spatial location pairs in the propagation sequence, calculate the gradient difference of temperature evolution trajectory and pressure evolution trajectory between adjacent misalignment spatial location pairs, and calculate the temperature-pressure coupling enhancement factor based on the gradient difference of temperature evolution trajectory and pressure evolution trajectory. Multiplying the attenuation transfer amount based on spatial spacing with the temperature-pressure coupling enhancement factor yields the transfer intensity of spatiotemporal deviation between adjacent locations.

6. The method according to claim 1, characterized in that, For each spatial location within the downstream spatial range, calculate the temperature compensation and pressure compensation required to offset the cumulative effect. Based on the response times of the temperature compensation and pressure compensation, determine the time interval between the application of the temperature compensation and the application of the pressure compensation, including: Obtain the cumulative spatiotemporal deviation of each spatial location within the downstream spatial location range, and decompose the cumulative spatiotemporal deviation into temperature dimension deviation component and pressure dimension deviation component; The amount of temperature compensation required to offset the cumulative effect is calculated based on the rate of change of the temperature dimension deviation component and the temperature evolution trajectory, and the amount of pressure compensation required to offset the cumulative effect is calculated based on the rate of change of the pressure dimension deviation component and the pressure evolution trajectory. The time required to offset the temperature dimension deviation component after the temperature compensation is applied is calculated as the response time of the temperature compensation; the time required to offset the pressure dimension deviation component after the pressure compensation is applied is calculated as the response time of the pressure compensation. Calculate the response time difference between the temperature compensation and the pressure compensation, and calculate the spatiotemporal propagation offset based on the response time difference and the material movement speed. Add the response time difference to the time advance corresponding to the spatiotemporal propagation offset to obtain the time interval between the application of the temperature compensation and the application of the pressure compensation.

7. The method according to claim 1, characterized in that, Based on the temperature compensation amount, pressure compensation amount, and time interval, compensation and control commands are output to the temperature control equipment and pressure control equipment corresponding to the downstream spatial location range, including: Based on the spatial mapping relationship between each spatial location within the downstream spatial location range and the temperature control equipment and pressure control equipment, determine the temperature control equipment and pressure control equipment corresponding to the downstream spatial location range; For temperature control equipment corresponding to the downstream spatial location range, the application time of temperature compensation is calculated based on the temperature compensation amount and time interval, and the temperature regulation range is calculated based on the control response characteristics of the temperature control equipment and the temperature compensation amount. For pressure control equipment corresponding to the downstream spatial location range, the application time of pressure compensation is calculated based on the pressure compensation amount and time interval, and the pressure regulation range is calculated based on the control response characteristics of the pressure control equipment and the pressure compensation amount. Based on the application time of the temperature compensation amount and the temperature control range, a temperature compensation control command is output to the temperature control equipment corresponding to the downstream spatial location range. Based on the timing of pressure compensation application and the pressure control amplitude, pressure compensation control commands are output to the pressure control equipment corresponding to the downstream spatial location range.

8. A temperature and pressure coordinated control system for the continuous foaming process of polyurethane sandwich panels, used to implement the method described in any one of claims 1-7, characterized in that, The system includes: The data acquisition module is used to collect temperature and pressure monitoring data from multiple spatial locations distributed along the material movement direction; The spatiotemporal modeling module is used to construct a spatiotemporal distribution matrix from temperature monitoring data and pressure monitoring data, and to extract the temperature evolution trajectory and pressure evolution trajectory at each spatial location. The imbalance identification module is used to calculate the difference in evolution rate and the difference in inflection point time between the temperature evolution trajectory and the pressure evolution trajectory, and to identify the spatial location of the imbalance and the corresponding spatiotemporal deviation. The propagation analysis module is used to track the propagation path of the spatiotemporal deviation along the direction of the board's movement based on the distribution of the misalignment spatial location in the direction of board movement, calculate the cumulative effect of the spatiotemporal deviation on the propagation path, and determine the downstream spatial location range of the cumulative effect. The compensation calculation module is used to calculate the temperature compensation and pressure compensation required to offset the cumulative effect for each spatial location within the downstream spatial location range, and to determine the time interval between the application of the temperature compensation and the application of the pressure compensation based on the response time of the temperature compensation and the response time of the pressure compensation. The control output module is used to output compensation and control commands to the temperature control equipment and pressure control equipment corresponding to the downstream spatial location range based on the temperature compensation amount, pressure compensation amount and time interval.

9. An electronic device, characterized in that, include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the computer program, implements the steps of the method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer program instructions that, when executed by a processor, implement the steps of the method as described in any one of claims 1 to 7.

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