Adaptive correction method and system based on cable insulation layer thickness monitoring

Abstract

The application belongs to the technical field of cable manufacturing. An adaptive correction method and system based on cable insulation layer thickness monitoring are proposed. According to the spatiotemporally synchronized laser array measurement data, the real-time center offset of the cable is determined. According to the spatiotemporally synchronized X-ray thickness measurement data, the cable thickness is determined. According to the spatiotemporally synchronized shooting obtained cable ellipse contour image, the ellipse major and minor axis ratio is determined. The real-time center offset of the cable, the cable thickness and the ellipse major and minor axis ratio are input into the extended Kalman filter to obtain the fused thickness, the fused concentricity and the fused ellipticity, and then the extrusion die pose compensation vector and the screw speed correction amount are determined. The corresponding actuator is driven according to the extrusion die pose compensation vector to adjust the extrusion die pose, and the screw speed is controlled according to the screw speed correction amount. The application solves the problems of one-sidedness of measurement, hysteresis of control and accumulation of deviation, and realizes the continuous and stable control of the geometric parameters of the cable insulation layer.

Description

Technical Field

[0001] This invention relates to the field of cable manufacturing technology, specifically to an adaptive correction method and system based on cable insulation layer thickness monitoring. Background Technology

[0002] Currently, the cable manufacturing industry commonly employs offline sampling inspection combined with manual intervention to monitor insulation quality. Typical technologies include periodically measuring insulation thickness using contact thickness gauges, acquiring cable outline data through laser scanners, and offline ellipticity analysis based on machine vision. Some systems use a single sensor for online monitoring, such as an X-ray thickness gauge or displacement sensor, triggering alarms based on preset thresholds.

[0003] However, existing cable extrusion correction control strategies have the following problems: (1) Measurement limitations and lack of synergy: Single-modal sensors (such as X-rays only or lasers only) cannot synchronously and comprehensively capture the complete geometric features (thickness, eccentricity and ellipticity) of the insulating layer; for example, although X-rays can penetrate to measure the thickness distribution, they are not sensitive to center offset and elliptical shape; laser arrays can detect eccentricity, but it is difficult to accurately obtain the internal thickness and elliptical contour; vision systems are good at contour extraction, but cannot penetrate the material to measure the thickness, and offline sampling methods cannot obtain transient defects and dynamic fluctuation information in continuous production; (2) Control lag and human dependence: The extrusion process has millisecond-level dynamic fluctuations (such as changes in melt pressure and traction speed); the correction of the cable is completely controlled by human intervention. The decision-making and response speed cannot match this dynamic characteristic, resulting in continuous accumulation of deviations; (3) Insufficient anti-interference capability and high false alarm rate: Single sensor data is easily affected by noise such as changes in the reflective properties of the material surface, mechanical vibration, and ambient temperature drift. The measurement results are unstable and have a high false alarm rate, making them difficult to serve as a reliable basis for high-precision closed-loop control. Summary of the Invention

[0004] To address the issues of measurement bias, control lag, and deviation accumulation, this invention provides an adaptive correction method and system based on cable insulation thickness monitoring. By integrating multimodal sensing information and conducting real-time collaborative analysis of the complete geometric state of the insulation layer, closed-loop correction can be completed quickly and automatically without human intervention, achieving continuous and stable control of the cable insulation layer's geometric parameters.

[0005] To achieve the above objectives, the embodiments of the present invention adopt the following technical solutions: In a first aspect, embodiments of the present invention provide an adaptive correction method based on cable insulation layer thickness monitoring.

[0006] An adaptive correction method based on cable insulation thickness monitoring includes the following steps: Based on the laser array measurement data after spatiotemporal synchronization, the real-time center offset of the cable is determined; based on the X-ray thickness measurement data after spatiotemporal synchronization, the cable thickness is determined; based on the cable elliptical profile image obtained after spatiotemporal synchronization, the ratio of the major and minor axes of the ellipse is determined. The real-time center offset of the cable, the cable thickness, and the ratio of the major and minor axes of the ellipse are input into the extended Kalman filter to obtain the fusion thickness, fusion concentricity, and fusion ellipticity. Based on the fusion thickness, fusion concentricity, and fusion ellipticity, the extrusion die pose compensation vector and screw speed correction amount are determined. The corresponding actuator is driven according to the extrusion die pose compensation vector to adjust the extrusion die pose, and the screw speed is controlled according to the screw speed correction amount.

[0007] In one implementation of the first aspect of the present invention, an XYZ rectangular coordinate system is established with the cable extrusion direction as the Z direction, and the Kalman filter is extended. The state vector at time t is a four-dimensional state vector, including Cable thickness at any time The center offset of the cable in the X direction at a given time. The center offset of the cable in the Y direction at time and The ratio of the major and minor axes of the ellipse at time t; according to The first element of the state vector at time step 1 determines the fusion thickness, according to The second and third elements of the state vector at time step 1 determine the fusion concentricity, according to... The fourth element of the state vector at time step 1 determines the fused ellipticity.

[0008] In one implementation of the first aspect of the present invention, determining the extrusion die pose compensation vector and the screw speed correction amount based on the fusion thickness, fusion concentricity, and fusion ellipticity includes: The eccentricity direction angle is determined based on the real-time center offset of the cable. The X-direction extrusion die position compensation amount and the Y-direction extrusion die position compensation amount are determined based on the eccentricity direction angle, fusion concentricity, proportional gain coefficient and integral gain coefficient. The tilt angle compensation amount is determined based on the fusion ellipticity, material calibration value and ellipticity deviation threshold. The combination of the X-direction extrusion die position compensation amount, the Y-direction extrusion die position compensation amount and the tilt angle correction amount is used as the extrusion die pose compensation vector. The speed correction amount is determined based on the process setting target values ​​for fusion thickness and insulation layer thickness, as well as the speed gain.

[0009] Furthermore, the extrusion die pose is adjusted according to the actuator driven by the extrusion die pose compensation vector, including: The difference between the X-direction extrusion die position compensation amount and the current X-direction extrusion die position, multiplied by the motor thrust gain, is used as the X-direction linear motor output thrust. The difference between the Y-direction extrusion die position compensation and the current Y-direction extrusion die position, multiplied by the motor thrust gain, is used as the output thrust of the Y-direction linear motor.

[0010] Furthermore, the screw speed is controlled based on the screw speed correction amount, including: The motor torque current correction amount is determined based on the current-speed conversion coefficient and the speed correction amount; The actual screw speed is obtained by multiplying the motor torque current correction amount by the speed gain and then adding it to the current screw speed.

[0011] In one implementation of the first aspect of the present invention, a real-time constraint process is further included, comprising: The production line speed, insulation layer perimeter, and adjustable coefficient are obtained. The ratio of the production line speed to the insulation layer perimeter, multiplied by the adjustable coefficient, is used as the periodic constraint threshold. The control cycle of the extrusion die pose and screw speed is less than or equal to the periodic constraint threshold.

[0012] In one implementation of the first aspect of the present invention, the gain coefficient of the extrusion die pose compensation vector is dynamically adjusted according to the spatial gradient of the fused concentricity and the curvature change of the fused ellipticity, thereby dynamically adjusting the extrusion die pose compensation vector, and the corresponding actuator is driven according to the dynamically adjusted extrusion die pose compensation vector to adjust the extrusion die pose.

[0013] Secondly, embodiments of the present invention provide an adaptive correction system based on cable insulation layer thickness monitoring.

[0014] An adaptive correction system based on cable insulation thickness monitoring includes: The data acquisition unit is configured to: determine the real-time center offset of the cable based on the laser array measurement data after spatiotemporal synchronization; determine the cable thickness based on the X-ray thickness measurement data after spatiotemporal synchronization; and determine the ratio of the major and minor axes of the ellipse based on the elliptical contour image of the cable obtained after spatiotemporal synchronization. The fusion calculation unit is configured to input the real-time center offset of the cable, the cable thickness, and the major and minor axis ratio of the ellipse into the extended Kalman filter to obtain the fusion thickness, fusion concentricity, and fusion ellipticity. The adaptive correction unit is configured to: determine the extrusion die pose compensation vector and the screw speed correction amount based on the fusion thickness, fusion concentricity and fusion ellipticity; drive the corresponding actuator to adjust the extrusion die pose based on the extrusion die pose compensation vector; and control the screw speed based on the screw speed correction amount.

[0015] Thirdly, embodiments of the present invention provide an adaptive correction system based on cable insulation layer thickness monitoring.

[0016] An adaptive correction system based on cable insulation thickness monitoring includes: The control terminal and the laser array, X-ray sensor and image acquisition device that communicate with the control terminal perform hardware clock synchronization on the laser array, X-ray sensor and image acquisition device to sample in the same time window; The laser array includes laser displacement sensors arranged at equal angular intervals around the circumference of the extruded cable. The laser displacement sensors are used to collect the radial distance on the cable surface and transmit the radial distance on the cable surface as the measurement data of the laser array to the control terminal. The X-ray sensor emits light perpendicular to the extrusion direction of the extruded cable. It is used to obtain the cable insulation thickness distribution function and transmits the cable insulation thickness distribution function as X-ray thickness measurement data to the control terminal. The image acquisition device monitors the cross-sectional image of the cable at a set tilt angle, which is used to acquire the elliptical outline image of the cable and transmit it to the control terminal. The control terminal is configured to execute the adaptive correction method based on cable insulation thickness monitoring according to the first aspect of the present invention.

[0017] Fourthly, embodiments of the present invention provide a computer device, including: a processor and a computer-readable storage medium; A processor, adapted to execute computer programs; A computer-readable storage medium stores a computer program that, when executed by a processor, implements the adaptive correction method based on cable insulation thickness monitoring, which is the first aspect of the present invention.

[0018] Fifthly, embodiments of the present invention provide a computer-readable storage medium storing a computer program adapted to be loaded by a processor and executed the adaptive correction method based on cable insulation thickness monitoring of the first aspect of the present invention.

[0019] In a sixth aspect, embodiments of the present invention provide a computer program product, which includes a computer program. When the computer program is executed by a processor, it implements the adaptive correction method based on cable insulation layer thickness monitoring of the first aspect of the present invention.

[0020] Compared with the prior art, the beneficial effects of the present invention are: This invention utilizes a spatially collaborative multimodal sensor network to synchronously acquire the complete geometric features of the insulation layer. Combined with clock synchronization and dynamic coupling data fusion technology, it eliminates measurement bias and noise interference, achieving accurate measurement of thickness, eccentricity, and ellipticity. Based on the fused thickness, concentricity, and ellipticity, it determines the extrusion die pose compensation vector and screw speed correction amount. The corresponding actuator is driven according to the extrusion die pose compensation vector to adjust the extrusion die pose, and the screw speed is controlled according to the screw speed correction amount. Closed-loop self-correction is completed within the extrusion fluctuation cycle, solving the problems of control lag and deviation accumulation. Through a dynamic gain adjustment mechanism, it adaptively matches changes in melt rheological properties, enabling adaptive adjustments during high-speed production and achieving continuous and stable control of the cable insulation layer's geometric parameters.

[0021] This invention integrates multi-source monitoring data from laser arrays, X-rays, and elliptical contour images, and obtains precise fusion parameters through extended Kalman filtering. Based on these parameters, the extrusion die pose and screw speed are adjusted in real time, achieving adaptive correction of cable insulation layer thickness, concentricity, and ellipticity. By utilizing multi-source information fusion to improve monitoring accuracy and using closed-loop control to dynamically compensate for production deviations, the stability of insulation layer processing quality is ensured.

[0022] The embodiments of this invention clarify the four-dimensional state vector composition of the extended Kalman filter, which directly corresponds to the cable thickness, X / Y direction center offset, and ellipticity. This ensures that the filtering state accurately matches the actual monitoring indicators, and that the calculation of fused thickness, concentricity, and ellipticity is more in line with the real state. This provides a reliable state benchmark for subsequent correction and improves the practicality of the filtering results.

[0023] This invention calculates the mold pose compensation vector (including position and tilt compensation) and screw speed correction amount based on the fusion parameters in different dimensions. By establishing the correlation between the compensation amount and the fusion index through parameters such as eccentricity direction angle and proportional-integral gain, the mold adjustment and speed control are more targeted, and the directional correction of insulation layer thickness, concentricity and ellipticity is achieved.

[0024] In this embodiment of the invention, the mold position compensation amount in the X / Y direction is converted into linear motor thrust (the product of position difference and thrust gain). Through quantified thrust control, the mold position is precisely adjusted, ensuring that the compensation amount is effectively converted into actual pose adjustment, thereby improving the mold positioning accuracy and response speed. The motor torque current correction amount is obtained from the speed correction amount through current-speed conversion, and then the actual screw speed is determined. The speed control requirement is converted into a current signal that the motor can execute, realizing precise and linear adjustment of the screw speed and ensuring that the insulation layer thickness is stable at the target value.

[0025] This invention determines the control cycle threshold based on production line speed, insulation layer perimeter, etc., constrains the adjustment frequency of mold pose and screw speed, so that the correction cycle is dynamically matched with the production line operation status, avoiding processing deviations caused by response lag and ensuring real-time correction effect; the gain coefficient of mold pose compensation vector is dynamically adjusted according to the fusion of concentricity spatial gradient and ellipticity curvature change, so that the compensation sensitivity is adaptively adjusted with the cable state change, and the adjustment force is enhanced when the parameters fluctuate drastically, improving the correction adaptability and accuracy under complex working conditions.

[0026] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0027] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0028] Figure 1 A schematic diagram of an adaptive correction system based on cable insulation thickness monitoring, provided as an exemplary embodiment of the present invention; Figure 2 A flowchart illustrating an adaptive correction method based on cable insulation layer thickness monitoring, provided as an exemplary embodiment of the present invention; Figure 3 A flowchart of spatial collaborative measurement provided as an exemplary embodiment of the present invention; Figure 4 A closed-loop control flowchart is provided as an exemplary embodiment of the present invention; Figure 5 A process control decision-making flowchart is provided as an exemplary embodiment of the present invention; Figure 6 A dynamic adaptive execution flowchart is provided as an exemplary embodiment of the present invention; Figure 7 A data fusion flowchart is provided as an exemplary embodiment of the present invention; Figure 8 A schematic diagram of an adaptive correction system based on cable insulation thickness monitoring, provided as another exemplary embodiment of the present invention; Figure 9 A schematic diagram of a computer device provided for an exemplary embodiment of the present invention. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0030] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0031] This embodiment proposes an adaptive correction system based on cable insulation thickness monitoring, such as... Figure 1 As shown, the master clock source sends hardware trigger pulses to the laser array, X-ray sensor, and industrial camera. The laser array outputs a radial distance set, the X-ray sensor outputs a thickness distribution, and the industrial camera outputs an elliptical profile. All three are input into a unified coordinate system transformation module. The data after unified coordinate system transformation is fed into an extended Kalman filter. At the same time, the mold pose adjustment and screw speed control will feed back signals to this filter. The output of the extended Kalman filter is sent to the state space model to obtain the fused thickness, fused concentricity, and fused ellipticity. These fusion results are fed into a pre-trained dynamic response model, which then generates mold pose compensation and screw speed correction, respectively. Mold pose compensation is used for mold pose adjustment, and screw speed correction is used for screw speed control, forming a closed-loop process.

[0032] In this embodiment, online monitoring and self-correction of cable insulation thickness, concentricity, and ellipticity are achieved through a multimodal sensor network, real-time data fusion, and closed-loop control, solving the problem of deviation accumulation in traditional open-loop systems. The system hardware is deployed according to the extrusion process, and the sensors used include a laser array, X-ray sensors, and an industrial camera (i.e., image acquisition equipment). In the laser array, multiple sets of laser displacement sensors are arranged circumferentially downstream of the extruder at 120° equal angular intervals (other angles, such as 90°, 60°, etc., can also be used) to collect the radial distance of the cable surface. , The sensor mounting angle; the X-ray sensor is a transmission sensor, mounted perpendicular to the extrusion direction, used to obtain the cable insulation thickness distribution function. ( (The angle is circumferential); the industrial camera views the cable cross-section from a 30° angle to capture an image of the cable's elliptical outline.

[0033] More specifically, the correction system in this embodiment includes a hardware platform, a software module, and an actuator. The hardware platform may optionally employ a Xilinx Zynq Ultra Scale+ MPSoC, an ARM Cortex-A53 quad-core processor (running a Linux system), and FPGA programmable logic (to achieve hardware-level synchronization and filtering acceleration). It is understood that other processors may also be used in other implementations (e.g., integrating a quad-core Cortex-A53 and dual Cortex-R5F real-time cores with a Lattice ECP5 FPGA; or, for example, a five-core RISC-V processor and a PolarFire FPGA). The software module specifically executes the adaptive correction method, employing a time synchronization engine, an extended Kalman filter (fusion algorithm), and a PID controller (compensation decision) to achieve spatiotemporal alignment, fusion calculation, and decision generation of multi-source data. The actuator is used to convert digital instructions into physical actions to achieve precise correction. The mold pose adjustment may optionally be implemented using a motor, and the screw speed control may optionally be implemented using a frequency converter.

[0034] The adaptive correction method based on cable insulation thickness monitoring executed by the software module in this embodiment, such as... Figure 2 As shown, the process includes the following: S201: Determine the real-time center offset of the cable based on the laser array measurement data after spatiotemporal synchronization; determine the cable thickness based on the X-ray thickness measurement data after spatiotemporal synchronization; determine the ratio of the major and minor axes of the ellipse based on the elliptical profile image of the cable obtained after spatiotemporal synchronization. S202: Input the real-time center offset of the cable, the cable thickness, and the ratio of the major and minor axes of the ellipse into the extended Kalman filter to obtain the fused thickness, fused concentricity, and fused ellipticity; S203: Determine the extrusion die pose compensation vector and screw speed correction amount based on the fusion thickness, fusion concentricity and fusion ellipticity. Drive the corresponding actuator to adjust the extrusion die pose based on the extrusion die pose compensation vector, and control the screw speed based on the screw speed correction amount.

[0035] In S201 of this embodiment, specifically, laser array measurement is performed using a laser array to calculate the center offset, thickness measurement is performed using X-rays, and elliptical contour measurement is performed using a camera. It should be noted that the specific sensor acquisition process is executed before the steps in S201. The process in S201 is used to process the acquired multi-source data, such as... Figure 3 As shown, the obtained center offset, thickness distribution, and elliptical contour are transformed into a unified coordinate system, and finally multimodal data is output.

[0036] In this implementation, the purpose of laser array measurement is to calculate the cable center offset through radial distance measurement, providing input for fusion concentricity, based on the original distance value of the laser sensor. As input, the center coordinates are calculated in real time: (1); (2); in, For the number of laser sensors ( ); These are the coordinates of the cable center, used to calculate the offset. ; For the first Radial distance measurements from a single laser sensor; For the first The installation angle of each sensor, and Let X be the coordinates of the cable center in the XY plane.

[0037] In this embodiment, the origin of the laser measurement coordinate system coincides with the theoretical center of the extrusion die. Therefore, this center coordinate is the real-time offset of the cable center relative to the theoretical center. (3); (4).

[0038] The laser array measurement process outputs real-time center offset ( , This converts the original distance values ​​into spatial offsets, providing input for subsequent data fusion.

[0039] The purpose of using X-rays for thickness measurement is to obtain the angular distribution of the insulation layer thickness, providing input for fusion thickness. Using the X-ray penetration signal (0°-360° circumferential angle) as input, the cable thickness distribution function is obtained based on the X-ray penetration signal. (5); Where γ is the cable circumference angle, The incident intensity of X-rays, Transmission intensity, The absorption coefficient of the material.

[0040] In this embodiment, the thickness observation value is calculated in the following way: (6); In formula (6), the integral operation is implemented through discrete summation in practical engineering systems, that is, the differential operation is performed by... Converted to the sensor's finite angular resolution in the circumferential direction. .

[0041] The process of using X-rays to measure thickness outputs the average thickness observation value. It overcomes surface reflection interference through radiation measurement, and has high resolution for thickness detection.

[0042] In this embodiment, the purpose of using a camera to measure the elliptical profile is to capture the shape of the cable cross-section and provide input for ellipticity fusion. The high-speed elliptical profile image captured by an industrial camera is used as input. Edge detection is performed on the image, and the Canny operator is used to extract the profile point set. For ellipse fitting, based on the extracted contour point set... The equation of the ellipse, solved using the least squares method, is as follows: (7); in, The length of the major axis of the ellipse. The length of the minor axis of the ellipse. Given the inclination angle of the ellipse, calculate it using the least squares method and output a set of parameter values ​​that minimize the overall error. , and .

[0043] In this embodiment, the axial ratio observation value is calculated in the following manner: (8); The process of measuring the ellipse profile using a camera outputs the observed value of the major and minor axis ratio. This technology enables high-precision ellipticity detection and overcomes measurement distortion caused by cable torsion.

[0044] This embodiment establishes a coordinate system for data acquired by multiple sensors. The aim is to address spatial reference differences between different sensors and ensure data fusion. A laser reference coordinate system (origin) is established using the local coordinate system data of each sensor as input. (Z-axis along the extrusion direction), X-ray data conversion, specifically including: (9); in,( ， ( ) represents the local coordinate system coordinates of the X-ray sensor. Install the X-ray sensor at the offset angle (obtained through calibration). , ) is the position compensation vector (obtained through calibration), , The translation compensation vector (obtained through calibration) outputs multimodal data in a unified coordinate system with small spatial alignment error, enabling the fusion of laser / X-ray / visual data.

[0045] In this embodiment, to eliminate fusion errors caused by the sampling time difference of multiple sensors and ensure data consistency in the time dimension, the clock synchronization mechanism forces all sensors to sample within the same time window through a hardware-level synchronization protocol. Using the local clock signal of each sensor (laser array, X-ray sensor, industrial camera) as input, a precision clock protocol is employed, and a master clock source is deployed. The master clock source broadcasts a hardware trigger pulse (pulse width = 100ns) to the sensor network. Slave devices trigger sampling on the rising edge of the pulse, achieving time synchronization. The synchronization constraints are: ≤100μs, where The maximum time difference between the actual sampling times of each sensor is used to output a time-aligned sampling data stream. At a production line speed of 30 m / min, the cable displacement caused by time synchronization error is small.

[0046] In S202 of this embodiment, specifically, as follows: Figure 4 As shown, the observation vector is first obtained, followed by state prediction, covariance prediction, Kalman gain calculation and state update in sequence, and then parameter output, finally outputting thickness, concentricity and ellipticity.

[0047] In this embodiment, multi-source sensor data is fused using an extended Kalman filter to eliminate noise interference and output high-precision estimates of the insulation layer's geometric parameters. State-space modeling is performed to establish a mathematical mapping relationship between the cable's geometric state and sensor observations, providing a theoretical basis for data fusion. Time-synchronized observation vectors are used... For input, where, The X / Y offset observations calculated for the laser array; The thickness observation value is from the X-ray sensor. This refers to the observed elliptic axis ratio of an industrial camera.

[0048] To characterize the core geometric features of the cable insulation layer, this embodiment defines a 4-dimensional state vector: (10); in, The thickness at time k; , The center offset at time k; Let be the ratio of the major axis a to the minor axis b of the ellipse at time k.

[0049] In this embodiment, the thickness T and X / Y offset ( , ), Major-minor axis ratio of the ellipse (where a is the length of the major axis and b is the length of the minor axis) serves as the core state quantity, fully characterizing the geometric features of the insulating layer.

[0050] Establish the state prediction equation: (11); in, The state at time k is predicted based on the data at time k-1. This is the state transition matrix (default is a 4×4 identity matrix, indicating continuous and stable states). This is the optimal state estimate at time k-1.

[0051] Establish a linear relationship between state variables and observed values: (12); in, The observation vector contains the laser distance value, X-ray thickness distribution value, and the lengths of the major and minor axes of the ellipse; H is a 4×4 observation diagonal matrix, whose non-zero elements are determined based on sensor calibration data, and its structure satisfies: (13); in, For thickness observation gain coefficient, The X-axis offset observation gain coefficient. The Y-axis offset observation gain coefficient, This refers to the ellipticity observation gain coefficient. It is a state vector; This is the observed noise vector.

[0052] Output state prediction value This process constructs a state-space model of thickness-offset-ellipticity, providing a mathematical framework for real-time filtering.

[0053] In this embodiment, covariance prediction is performed to quantify the uncertainty of state prediction and reflect the model's reliability. The covariance matrix at time k-1 is used as the basis for this prediction. As input, generate the prediction covariance matrix: (14); in, Predict the covariance matrix at time k; The covariance is estimated at time k-1; Q is the process noise covariance (inherent system fluctuation). Transpose of the state transition matrix; Output prediction covariance This process dynamically evaluates the reliability of the model and provides a basis for Kalman gain calculation.

[0054] In this implementation, Kalman gain calculation is performed to dynamically allocate the weights of predicted and observed values, achieving optimal fusion to predict covariance. Using the observation matrix H as input, the Kalman gain is calculated: (15); in, This is the Kalman gain matrix (weighting coefficients); Transpose the observation matrix; To observe the noise covariance (sensor calibration parameter); Find the inverse of the matrix.

[0055] When the sensor accuracy is high ( (small) increases Trust the observations; when the model is reliable ( (small) increases Trust the predicted value, and finally output the Kalman gain. This process achieves an optimal balance between noise suppression and state correction.

[0056] In this embodiment, the purpose of state updating and parameter output is to fuse predicted and observed values ​​and output the optimal geometric parameter estimate, based on the predicted state value. Observation vector and Kalman gain As input, the observed residuals are used to correct the predicted values ​​for state updates: (16); in, This refers to the observation residual (the deviation between the actual and the predicted values).

[0057] Covariance update: (17); in, It is a 4×4 identity matrix.

[0058] Parameter generation: (18); in, The first element of the state vector. This is the second element of the state vector, and so on. For fusion thickness; To achieve concentricity; To incorporate ellipticity.

[0059] Output fusion thickness , integration and concentricity Blending Ellipticity This process improves the sensitivity of thickness measurement and eccentricity detection.

[0060] In S203 of this embodiment, as Figure 5 As shown, specifically, based on the pre-trained dynamic response model, a real-time compensation instruction is generated based on the fusion parameters to dynamically suppress quality deviations. This includes: receiving the fusion parameters, and then determining whether the thickness, concentricity, and ellipticity are out of tolerance; if the thickness is out of tolerance, ΔV is calculated; if the concentricity is out of tolerance, ΔX and ΔY are calculated; if the ellipticity is out of tolerance, Δα is calculated; finally, regardless of the above judgment results, a compensation instruction is output.

[0061] In this embodiment, the purpose of determining the deviation threshold is to identify the type of geometric deviation that needs to be corrected, activate the corresponding compensation strategy, and fuse the parameters. Given the input, the decision logic is as follows: Thickness deviation: At that time, thickness compensation is activated. Thickness deviation threshold (preset parameter); Eccentricity deviation: when At that time, eccentricity compensation is activated. Concentricity deviation threshold (preset parameter); Ellipticity deviation: when At that time, ellipticity compensation is activated. Ellipticity deviation threshold (preset parameter); Output compensation activation flags (thickness, eccentricity, ellipticity), this process enables accurate identification of deviation types and avoids invalid compensation actions.

[0062] In this embodiment, compensation amount calculation is performed to generate accurate compensation instructions based on the type and degree of deviation, in order to fuse parameters. The position compensation calculation (calculating the eccentricity direction angle) is performed using the deviation flag as input: (19); Integrating concentricity Decomposed into X and Y directions, the current center offset deviation components are obtained: (20); (twenty one); A PID control algorithm is adopted, with the deviation component... and As input, calculate the mold position compensation amount. and : (twenty two); (twenty three); in, and These are the initially set proportional and integral gain coefficients (adjusted according to the extruder response characteristics).

[0063] Tilt compensation calculation (for ellipticity): (twenty four); in, The initial material calibration values ​​are adjusted based on rheological properties. Rotational speed correction calculation (for thickness): (25); in, This is the speed gain (determined based on the screw characteristic curve). The process setting target value for insulation layer thickness.

[0064] Output mold pose compensation vector Screw speed correction amount This process compensates for the instruction generation delay and improves response speed.

[0065] like Figure 6 As shown, the process of S201-S203 in this embodiment can achieve closed-loop execution, converting digital compensation commands into physical actions, completing real-time correction, and continuing synchronous data acquisition after correction. Then, spatial coordinate transformation is performed, followed by dynamic coupling fusion. After that, it is determined whether the parameters are out of tolerance. If they are out of tolerance, process reverse control decisions are made, and mold pose compensation and screw speed correction are performed respectively. Then, closed-loop execution and real-time correction are performed, and synchronous data acquisition is performed again after completion within the extrusion fluctuation cycle. If they are not out of tolerance, monitoring continues, and then it returns to the synchronous data acquisition stage.

[0066] In this embodiment, actuator control is performed to achieve high-precision conversion between compensation instructions and physical execution, in order to compensate vectors. and speed correction amount For input.

[0067] (1) Perform mold displacement control (directly change the melt flow field distribution), and the actuator is a linear motor.

[0068] X-axis direction: (26); in, To output thrust to the X-axis linear motor, This is the thrust gain of the motor; The current X-axis position of the mold (encoder feedback); Y-axis direction: (27); To output thrust to the Y-axis linear motor, .

[0069] (2) Mold tilt angle control, the actuator is a piezoelectric ceramic actuator.

[0070] (28); in, The driving voltage for piezoelectric ceramics, It is the voltage-angle conversion factor (determined by the properties of piezoelectric materials). This is the real-time angle from the tilt sensor.

[0071] (3) Screw speed control, the actuator adopts a vector frequency converter.

[0072] (29); in, Motor torque current correction amount This is the current-to-speed conversion coefficient; The actual rotational speed of the screw is: (30); in, This refers to the actual rotational speed of the screw. This represents the current rotational speed of the screw.

[0073] By adjusting the torque current Change the screw speed; Output the actual mold pose ( , , Screw speed .

[0074] This embodiment incorporates a real-time constraint mechanism to ensure that the correction action is completed within the process fluctuation cycle, avoiding delayed control, with the production line speed v and the perimeter of the insulation layer as inputs.

[0075] The control cycle constraint is: (31); in, Indicates production line speed. This is an adjustable coefficient.

[0076] Limit cable movement distance during calibration to ≤ perimeter times, default value =0.1 (balancing response speed and stability).

[0077] Example calculation: ; (32); Output actual control cycle This process ensures the timeliness of closed-loop control and avoids correction lag.

[0078] In this embodiment, compensation parameters are optimized in real time based on the dynamic characteristics of insulation layer deformation to adapt to changes in operating conditions. The gain coefficient of the extrusion die pose compensation vector is dynamically adjusted based on the spatial gradient of the fusion concentricity and the curvature change of the fusion ellipticity, thereby dynamically adjusting the extrusion die pose compensation vector. The corresponding actuator is then driven by the dynamically adjusted extrusion die pose compensation vector to adjust the extrusion die pose. Figure 7 As shown, the fusion parameters are first input, and then the gradient ▽ĉ and curvature are calculated simultaneously. Next, the gain coefficient is calculated, then the adaptive gain is applied, and then the compensation vector is generated to ensure that the mechanical constraints are met.

[0079] (1) Dynamic characteristic extraction is performed to quantify the spatiotemporal variation characteristics of geometric parameters, providing a basis for gain adjustment. The input data is: fused concentricity time series. fusion of ellipticity time series Production line speed Sampling interval Because the cable travels at a speed Continuous extrusion, time interval The physical distance the cable moves in the extrusion direction (Z-axis): (33); in, This represents the extrusion displacement of the cable between adjacent sampling points; this displacement increment... It is a time series and A key bridge for transforming spatial variation characteristics.

[0080] Gradient representation of fusion concentricity The rate of change in the extrusion direction. Calculated using the concentricity values ​​at the current time k and the previous time k-1: (34); The rate of change of concentricity per unit length reflects the degree of deviation in the eccentric direction. Perform ellipticity curvature calculations, specifically including: curvature Characterizing fusion ellipticity The rate of change of the rate of change in the extrusion direction reflects the "acceleration" or degree of curvature of the ellipticity change. It is calculated using the ellipticity values ​​at the current time k, the previous time k-1, and the time two moments before k-2: (35); The second derivative of the ellipticity variation characterizes the cross-sectional deformation acceleration; a large positive or negative value indicates this. The value indicates that the ellipticity is changing at an accelerating rate.

[0081] Output dynamic characteristic parameters This process captures the dynamic evolution characteristics of the insulation layer's geometric deformation in spatial distribution in real time, especially the rate and acceleration of change, providing a sensitive input signal for gain adaptation and significantly reducing system response delay.

[0082] (2) Perform gain adaptive control, adjust the control gain in real time based on dynamic characteristics to suppress overshoot and oscillation, and satisfy mechanical limit constraints. Calculate and adjust the mold pose compensation vector in real time. Gain coefficient Its core principle is: when the deformation changes drastically (large gradient or large curvature), the gain is automatically reduced to avoid overshoot and oscillation; when the deformation changes gently, the gain can be appropriately increased to speed up the response.

[0083] With dynamic characteristic parameters As input, an adaptive strategy based on the inverse relationship of dynamic characteristic parameters is adopted, and a minimum constant is introduced. To prevent the denominator from being zero and ensure numerical stability: X- and Y-direction displacement gain adjustment (response to concentricity gradient) ): (36); (37); in, and These are the displacement compensation gain coefficients in the X and Y directions, respectively; and These represent the maximum allowable adjustment amounts in the X and Y directions, respectively; ε is for preventing division by zero. Let be the Euclidean norm of the gradient vector; Tilt gain (Response ellipticity curvature) )for: (38); in, It is the maximum allowable adjustment of the tilt angle.

[0084] ladder or curvature The larger the value (the more drastic the deformation), the higher the calculated gain. , , Automatically decreasing, resulting in a final compensation amount It is more gradual, avoiding sudden movements that could lead to instability.

[0085] (3) Apply the gain to generate the compensation vector, and calculate the compensation amount. In the formula, this adaptive gain is used Replace the original fixed gain coefficient (i.e. , , ),For example: The eccentricity compensation amount can be calculated as follows: (39); (40); The calculation of tilt compensation may become: (41); Output adaptive gain coefficient: (42); During periods of drastic deformation of the insulating layer, the control gain is automatically reduced to make the system response smoother, reduce overshoot, and adapt to changes in melt viscosity.

[0086] Figure 8 An adaptive correction system based on cable insulation thickness monitoring is shown, comprising: The data acquisition unit 801 is configured to: determine the real-time center offset of the cable based on the laser array measurement data after time-space synchronization, determine the cable thickness based on the X-ray thickness measurement data after time-space synchronization, and determine the major and minor axis ratio of the ellipse based on the cable elliptical contour image obtained after time-space synchronization. The fusion calculation unit 802 is configured to input the real-time center offset of the cable, the cable thickness, and the major and minor axis ratio of the ellipse into the extended Kalman filter to obtain the fusion thickness, fusion concentricity, and fusion ellipticity. The adaptive correction unit 803 is configured to: determine the extrusion die pose compensation vector and the screw speed correction amount based on the fusion thickness, fusion concentricity and fusion ellipticity; drive the corresponding actuator to adjust the extrusion die pose based on the extrusion die pose compensation vector; and control the screw speed based on the screw speed correction amount.

[0087] It is understood that the aforementioned units can be individually or entirely merged into one or more other units, or some of the units can be further divided into multiple functionally smaller units. This achieves the same operation without affecting the technical effects of the embodiments of the present invention. The aforementioned units are based on logical functional division. In practical applications, the function of one unit can be implemented by multiple units, or the function of multiple units can be implemented by one unit. In other embodiments of the present invention, the system may also include other units. In practical applications, these functions can also be implemented with the assistance of other units, and can be implemented collaboratively by multiple units.

[0088] According to another embodiment of the present invention, the system of this embodiment can be constructed by running a computer program (including program code) capable of performing the steps involved in the corresponding method of the present invention on a general-purpose computing device, such as a computer, which includes processing elements and storage elements such as a central processing unit (CPU), random access memory (RAM), and read-only memory (ROM). The computer program can be recorded on, for example, a computer-readable recording medium, loaded into the aforementioned computing device through the computer-readable recording medium, and run therein.

[0089] Figure 9 A computer device is shown, which includes a processor 901, a communication interface 902, and a computer-readable storage medium 903. The processor 901, communication interface 902, and computer-readable storage medium 903 can be connected via a bus or other means.

[0090] The communication interface 902 is used to receive and send data. The computer-readable storage medium 903 can be stored in the memory of the electronic device. The computer-readable storage medium 903 is used to store computer programs, which include program instructions. The processor 901 is used to execute the program instructions stored in the computer-readable storage medium 903.

[0091] The processor 901 is the computing and control core of electronic devices. It is suitable for implementing one or more instructions, specifically for loading and executing one or more instructions to achieve corresponding methods or functions.

[0092] Processor 901 is configured to perform the following procedure: Based on the laser array measurement data after spatiotemporal synchronization, the real-time center offset of the cable is determined; based on the X-ray thickness measurement data after spatiotemporal synchronization, the cable thickness is determined; based on the cable elliptical profile image obtained after spatiotemporal synchronization, the ratio of the major and minor axes of the ellipse is determined. The real-time center offset of the cable, the cable thickness, and the ratio of the major and minor axes of the ellipse are input into the extended Kalman filter to obtain the fusion thickness, fusion concentricity, and fusion ellipticity. Based on the fusion thickness, fusion concentricity, and fusion ellipticity, the extrusion die pose compensation vector and screw speed correction amount are determined. The corresponding actuator is driven according to the extrusion die pose compensation vector to adjust the extrusion die pose, and the screw speed is controlled according to the screw speed correction amount.

[0093] This invention also provides a computer-readable storage medium, which is a memory device in an electronic device for storing programs and data. It is understood that the computer-readable storage medium here may include both built-in storage media in the electronic device and extended storage media supported by the electronic device. The computer-readable storage medium provides storage space for storing the processing system of the electronic device.

[0094] Furthermore, this storage space also contains one or more instructions suitable for loading and execution by the processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer-readable storage medium here can be high-speed RAM memory or unstable memory, such as at least one disk storage device; optionally, it can also be at least one computer-readable storage medium located remotely from the aforementioned processor.

[0095] In one embodiment, the computer-readable storage medium stores one or more instructions; the processor loads and executes the one or more instructions stored in the computer-readable storage medium to perform the following process: Based on the laser array measurement data after spatiotemporal synchronization, the real-time center offset of the cable is determined; based on the X-ray thickness measurement data after spatiotemporal synchronization, the cable thickness is determined; based on the cable elliptical profile image obtained after spatiotemporal synchronization, the ratio of the major and minor axes of the ellipse is determined. The real-time center offset of the cable, the cable thickness, and the ratio of the major and minor axes of the ellipse are input into the extended Kalman filter to obtain the fusion thickness, fusion concentricity, and fusion ellipticity. Based on the fusion thickness, fusion concentricity, and fusion ellipticity, the extrusion die pose compensation vector and screw speed correction amount are determined. The corresponding actuator is driven according to the extrusion die pose compensation vector to adjust the extrusion die pose, and the screw speed is controlled according to the screw speed correction amount.

[0096] The present invention also provides a computer program product or computer program comprising computer instructions stored in a computer-readable storage medium. A processor of an electronic device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the electronic device to perform the following process: Based on the laser array measurement data after spatiotemporal synchronization, the real-time center offset of the cable is determined; based on the X-ray thickness measurement data after spatiotemporal synchronization, the cable thickness is determined; based on the cable elliptical profile image obtained after spatiotemporal synchronization, the ratio of the major and minor axes of the ellipse is determined. The real-time center offset of the cable, the cable thickness, and the ratio of the major and minor axes of the ellipse are input into the extended Kalman filter to obtain the fusion thickness, fusion concentricity, and fusion ellipticity. Based on the fusion thickness, fusion concentricity, and fusion ellipticity, the extrusion die pose compensation vector and screw speed correction amount are determined. The corresponding actuator is driven according to the extrusion die pose compensation vector to adjust the extrusion die pose, and the screw speed is controlled according to the screw speed correction amount.

[0097] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed in this invention can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can implement the described functions using different methods for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0098] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. A computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the flow or function according to the embodiments of the present invention is generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in or transmitted through a computer-readable storage medium. The computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic cable, digital cable) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that a computer can access or a data processing device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid-state drive), etc.

[0099] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An adaptive correction method based on cable insulation layer thickness monitoring, characterized in that, The process includes the following: Based on the laser array measurement data after spatiotemporal synchronization, the real-time center offset of the cable is determined; based on the X-ray thickness measurement data after spatiotemporal synchronization, the cable thickness is determined; based on the cable elliptical profile image obtained after spatiotemporal synchronization, the ratio of the major and minor axes of the ellipse is determined. The real-time center offset of the cable, the cable thickness, and the ratio of the major and minor axes of the ellipse are input into the extended Kalman filter to obtain the fusion thickness, fusion concentricity, and fusion ellipticity. Based on the fusion thickness, the fusion concentricity, and the fusion ellipticity, the extrusion die pose compensation vector and the screw speed correction amount are determined. The corresponding actuator is driven according to the extrusion die pose compensation vector to adjust the extrusion die pose, and the screw speed is controlled according to the screw speed correction amount.

2. The adaptive correction method based on cable insulation layer thickness monitoring as described in claim 1, characterized in that, Establish an XYZ Cartesian coordinate system with the cable extrusion direction as the Z-axis, and extend the Kalman filter. The state vector at time t is a four-dimensional state vector, including Cable thickness at any time The center offset of the cable in the X direction at a given time. The center offset of the cable in the Y direction at time and The ratio of the major and minor axes of the ellipse at time t; according to The first element of the state vector at time step 1 determines the fusion thickness, according to The second and third elements of the state vector at time step 1 determine the fusion concentricity, according to... The fourth element of the state vector at time t determines the fused ellipticity.

3. The adaptive correction method based on cable insulation layer thickness monitoring as described in claim 1, characterized in that, Based on the fusion thickness, the fusion concentricity, and the fusion ellipticity, the extrusion die pose compensation vector and the screw speed correction amount are determined, including: The eccentricity direction angle is determined based on the real-time center offset of the cable. The X-direction extrusion die position compensation amount and the Y-direction extrusion die position compensation amount are determined based on the eccentricity direction angle, the fusion concentricity, the proportional gain coefficient, and the integral gain coefficient. The tilt angle compensation amount is determined based on the fusion ellipticity, the material calibration value, and the ellipticity deviation threshold. The combination of the X-direction extrusion die position compensation amount, the Y-direction extrusion die position compensation amount, and the tilt angle correction amount is used as the extrusion die pose compensation vector. The speed correction amount is determined based on the process setting target values ​​for fusion thickness and insulation layer thickness, as well as the speed gain.

4. The adaptive correction method based on cable insulation layer thickness monitoring as described in claim 3, characterized in that, The extrusion die pose is adjusted by driving the corresponding actuator according to the extrusion die pose compensation vector, including: The difference between the X-direction extrusion die position compensation amount and the current X-direction extrusion die position, multiplied by the motor thrust gain, is used as the X-direction linear motor output thrust. The difference between the Y-direction extrusion die position compensation and the current Y-direction extrusion die position, multiplied by the motor thrust gain, is used as the output thrust of the Y-direction linear motor.

5. The adaptive correction method based on cable insulation layer thickness monitoring as described in claim 3, characterized in that, Controlling the screw speed according to the screw speed correction amount includes: The motor torque current correction amount is determined based on the current-speed conversion coefficient and the speed correction amount; The actual screw speed is obtained by multiplying the motor torque current correction amount by the speed gain and then adding it to the current screw speed.

6. The adaptive correction method based on cable insulation layer thickness monitoring as described in any one of claims 1-5, characterized in that, It also includes a real-time constraint process, including: The production line speed, insulation layer perimeter, and adjustable coefficient are obtained. The ratio of the production line speed to the insulation layer perimeter, multiplied by the adjustable coefficient, is used as the periodic constraint threshold. The control period of the extrusion die pose and the screw speed is less than or equal to the periodic constraint threshold.

7. The adaptive correction method based on cable insulation thickness monitoring as described in any one of claims 1-5, characterized in that, Based on the spatial gradient of the fused concentricity and the curvature change of the fused ellipticity, the gain coefficient of the extrusion die pose compensation vector is dynamically adjusted, thereby dynamically adjusting the extrusion die pose compensation vector. The corresponding actuator is then driven according to the dynamically adjusted extrusion die pose compensation vector to adjust the extrusion die pose.

8. An adaptive correction system based on cable insulation thickness monitoring, characterized in that, include: The data acquisition unit is configured to determine the real-time center offset of the cable based on the measurement data of the laser array after spatiotemporal synchronization. The cable thickness is determined based on the X-ray thickness measurement data after spatiotemporal synchronization; the major and minor axis ratios of the ellipse are determined based on the cable elliptical profile image obtained after spatiotemporal synchronization. The fusion calculation unit is configured to input the real-time center offset of the cable, the cable thickness, and the major and minor axis ratio of the ellipse into the extended Kalman filter to obtain the fusion thickness, fusion concentricity, and fusion ellipticity. The adaptive correction unit is configured to: determine the extrusion die pose compensation vector and the screw speed correction amount based on the fusion thickness, the fusion concentricity and the fusion ellipticity; drive the corresponding actuator to adjust the extrusion die pose based on the extrusion die pose compensation vector; and control the screw speed based on the screw speed correction amount.

9. An adaptive correction system based on cable insulation thickness monitoring, characterized in that, include: The control terminal and the laser array, X-ray sensor and image acquisition device that communicate with the control terminal perform hardware clock synchronization on the laser array, X-ray sensor and image acquisition device to sample in the same time window; The laser array includes laser displacement sensors arranged at equal angular intervals around the circumference of the extruded cable. The laser displacement sensors are used to collect the radial distance on the cable surface and transmit the radial distance on the cable surface as the laser array measurement data to the control terminal. The X-ray sensor emits light perpendicular to the extrusion direction of the extruded cable, and is used to obtain the cable insulation layer thickness distribution function, and transmit the cable insulation layer thickness distribution function as X-ray thickness measurement data to the control terminal. The image acquisition device monitors the cross-sectional image of the cable at a set tilt angle, and is used to acquire the elliptical outline image of the cable and transmit it to the control terminal. The control terminal is configured to execute the adaptive correction method based on cable insulation layer thickness monitoring as described in any one of claims 1-7.

10. A computer device, characterized in that, include: Processor and computer-readable storage media; A processor, adapted to execute computer programs; A computer-readable storage medium storing a computer program, which, when executed by the processor, implements the adaptive correction method based on cable insulation thickness monitoring as described in any one of claims 1 to 7.

11. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program adapted to be loaded by a processor and executed as described in any one of claims 1 to 7, the adaptive correction method based on cable insulation thickness monitoring.

12. A computer program product, characterized in that, The computer program product includes a computer program that, when executed by a processor, implements the adaptive correction method based on cable insulation thickness monitoring as described in any one of claims 1 to 7.

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