Computer film cutting production application management system

Abstract

The invention discloses a computer film cutting production application management system, and belongs to the technical field of production processing control. The technical problem that in an existing scheme, the film tension self-adaptive control effect is poor is solved. The high-precision encoder is used for achieving tension monitoring of a thin film transmission full path, integrating multi-dimensional data such as linear speed difference, pressure deviation and environment temperature, and implementing a dynamic error compensation mechanism, so that the system still keeps stable precision in different temperature environments, and the real-time control requirement of high-speed film cutting is met; the position weight and the film thickness are coupled through a tension sensitivity coefficient, adjacent section speed difference feedback correction is introduced, and self-adaptive adjustment of films with different thicknesses is achieved through threshold value dynamic configuration and a sensitivity coefficient formula; through PID closed-loop feedback and a self-adaptive integral separation mode, integration is started when tension fluctuation is abnormal, delay is adjusted through cooperation of a sampling period and current, it is ensured that the response time of tension sudden change is controlled within the standard response time, and the film breaking risk is avoided.

Description

Technical Field

[0001] This invention relates to the field of production and processing control technology, specifically to a computer-based membrane cutting production application management system. Background Technology

[0002] Computerized film cutting production is an automated production process that uses computer control technology to cut thin film materials. Rolls or sheets of film material are precisely cut according to the shape and size of the design drawings by mechanical pressure (using a die) or laser cutting.

[0003] The film tension needs to be controlled within the range of 2~10N. Too much tension will cause stretching deformation, while too little tension will cause belt deviation. Most existing computer-controlled film cutting production applications still rely on a single control scheme to control film tension, which has the drawback of poor adaptive control of film tension. Summary of the Invention

[0004] The purpose of this invention is to provide a computer-based membrane cutting production application management system to solve the technical problem of poor adaptive control of film tension in existing solutions.

[0005] The objective of this invention can be achieved through the following technical solutions: A computer-aided membrane cutting production application management system, comprising: The film segment monitoring data processing module collects real-time operating parameters of each segment of the film through a high-resolution encoder group distributed along the film transport path, calculates the current tension value of each segment of the film, and performs dynamic error compensation and data verification; the operating parameters include film linear velocity, roller angular displacement and tension roller pressure deviation; Thin film segment dynamic operation control correction module: obtains the tension deviation between the current tension value of each thin film segment and the preset tension threshold, generates the target braking torque of the multi-segment magnetic powder brake group through the multi-segment coupling control algorithm, and dynamically allocates the braking torque according to the tension sensitivity coefficient of each segment. The braking torque allocation ratio of adjacent segments is corrected in real time through speed difference feedback. Closed-loop control and adaptive adjustment module: Based on the generated final output braking torque, the excitation current of the magnetic powder brake group is adjusted, and PID closed-loop control is constructed through the tension feedback value collected in real time by the encoder group. When the tension fluctuation amplitude is less than or equal to the amplitude threshold for several consecutive sampling cycles, the adaptive integral separation mode is triggered to reduce the overshoot.

[0006] Preferably, based on the collected and processed roller angular displacement θ, film linear velocity v, and tension roller pressure deviation ΔP, the current tension value of each section of the film is calculated using a formula. The expression involved is: ;in, This is the position correction factor; These are the linear velocities of the thin film in the (i+1)th segment and the i-th segment, respectively; Where A is the film density; A is the cross-sectional area of ​​the film. This is the wrap angle of the encoder corresponding to the roller; The deviation of the tension roller pressure in the i-th segment; For pressure-tension conversion efficiency.

[0007] Preferably, when implementing dynamic error compensation, the ambient temperature w is collected by a temperature sensor installed near the encoder, and the elastic modulus E of the thin film is corrected. The relevant expression is: ;in, This is the standard elastic modulus at 25℃.

[0008] Preferably, during data verification, when the tension values ​​of two adjacent segments... and When the deviation exceeds the deviation threshold, an anomaly flag is triggered, and backup encoder data is automatically activated.

[0009] Preferably, the tension sensitivity coefficient of each segment of the film is calculated based on the encoder position weight and the film thickness; when dynamically allocating the braking torque based on the tension sensitivity coefficient, the obtained tension deviation and tension sensitivity coefficient are used as inputs, and the target braking torque is generated through a multi-segment coupling control algorithm.

[0010] Preferably, the torque distribution ratio of adjacent segments is corrected in real time through speed difference feedback to obtain the corrected braking torque; based on the target braking torque and the speed difference feedback correction term, the final output braking torque is output and sent to the multi-segment magnetic powder brake assembly via CAN bus.

[0011] Preferably, based on the generated final output braking torque, the target excitation current of the magnetic powder brake is calculated through a current-torque conversion model, and the target excitation current is output through a PWM controller to achieve accurate mapping of braking torque to current.

[0012] Preferably, when constructing a PID closed-loop control using the tension feedback value collected in real time by the encoder group, the current tension value of the film is used as the feedback input and compared with the preset process tension threshold to construct a position-type PID controller, and the output value of the PID controller for different sampling periods is calculated; the output value of the PID controller calculated in the kth sampling period is sent to the PWM controller, and the PWM controller converts the output value of the PID controller into an excitation current, which is applied to the magnetic powder brake.

[0013] Preferably, when the tension fluctuation amplitude of three consecutive sampling periods is ≤ ±M%, M > 0, the integral term is enabled to eliminate steady-state error; otherwise, the integral term is kept at 0 to avoid overshoot caused by integral saturation.

[0014] Preferably, the integral term is ;in, The integral coefficient; This is for input error; is the sampling period time interval; k is the sampling period number; j is the index variable of the discrete-time sampling point.

[0015] Compared to existing solutions, the beneficial effects achieved by this invention are: This invention achieves tension monitoring throughout the entire film transmission path using a high-precision encoder, which effectively improves spatial resolution and significantly enhances accuracy compared to traditional single-point detection. By integrating multi-dimensional data such as linear velocity difference, pressure deviation, and ambient temperature, tension calculation errors can be effectively controlled, solving the dynamic response lag problem caused by single velocity feedback. Through the implementation of a dynamic error compensation mechanism, the system maintains stable accuracy under different temperature environments, meeting the real-time control requirements of high-speed film cutting and improving the system's reliability and robustness.

[0016] This invention effectively improves the torque adjustment accuracy of high-priority segments by coupling position weights with film thickness using a tension sensitivity coefficient, effectively solving the problem of local tension runaway caused by traditional uniform distribution. By introducing feedback correction for speed differences between adjacent segments, tension fluctuations are suppressed within ±1.2%, improving the adaptability to dynamic tension requirements in high-speed film cutting. Through dynamic threshold configuration and sensitivity coefficient formula, it is compatible with film cutting scenarios of multiple materials such as PET, PE, and aluminum foil without hardware replacement, achieving adaptive adjustment of films of different thicknesses.

[0017] This invention effectively improves tension control accuracy through PID closed-loop feedback, meeting the process requirements of precision film cutting. The adaptive integral separation mode activates integration when tension fluctuations are abnormal, significantly reducing overshoot and preventing film stretching deformation or wrinkling. The temperature-compensated current conversion model and dynamic current upper limit enable the system to operate stably in different temperature environments, enhancing its adaptability to various operating conditions. By combining the sampling period with current adjustment delay, the response time to sudden tension changes is ensured to be controlled within the standard reaction time, avoiding the risk of film breakage. Attached Figure Description

[0018] The invention will now be further described with reference to the accompanying drawings.

[0019] Figure 1 This is a flowchart illustrating the operation of a computer-based membrane cutting production application management system according to the present invention. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] like Figure 1 As shown, this invention is a computer-based membrane cutting production application management system, comprising: The film segment monitoring data processing module: This module collects real-time operating parameters of each film segment using a distributed array of high-resolution encoders along the film transport path, calculates the current tension value of each segment, and performs dynamic error compensation and data verification. Operating parameters include film linear velocity, roller angular displacement, and tension roller pressure deviation. Specific steps include: Before collecting real-time operating parameters for each segment of the thin film, the encoder group is deployed in a distributed manner and its parameters are configured; specifically: Three sets of high-resolution encoders are deployed at equal intervals along the film transport path, such as the unwinding section, traction section, and rewinding section. Each set includes one rotary encoder and one tension roller pressure sensor, as follows: Installation locations: Group 1 is located 0.5m from the unwinding roll exit and is used to monitor initial tension; Group 2 is located in the middle section of the traction roll group and is used to monitor transmission tension; Group 3 is located 0.5m from the take-up roll inlet and is used to monitor take-up tension. Mechanical connection: The encoder is coaxially connected to the transmission roller via a flexible coupling to ensure gapless angular displacement measurement. The resolution is set to 2500 lines / revolution, and the sampling frequency is set to 2.5kHz via the PLC control module, which is more than twice the Nyquist frequency corresponding to the maximum linear speed of the film. Pressure sensor: Integrated into the tension roller bearing housing, it adopts a strain gauge type pressure sensor with a range of 0-500N and an accuracy of ±0.2%FS, and is used to collect the tension roller pressure deviation ΔP. The encoder group synchronously collects the roller angular displacement, film linear velocity, and tension roller pressure deviation, and converts them into physical quantities; Wherein, the roller angular displacement θ: the encoder outputs 2500 pulses per revolution, and the pulse count N is accumulated by the counting module. The conversion formula is: ; Film linear velocity v: Calculate the linear velocity based on the roller diameter D. ;in, The sampling period time interval; The tension roller pressure deviation ΔP is directly acquired by a pressure sensor, and the difference between the current pressure value and the preset reference pressure is calculated and output in real time. Based on the collected data, including roller angular displacement θ, film linear velocity v, and tension roller pressure deviation ΔP, the current tension value of each film segment is calculated using a formula. The expression involved is: ;in, This is the position correction factor, which is positively correlated with the roller stiffness at the encoder mounting position. The value is 1.1 for the unwinding section and 0.95 for the winding section. These are the linear velocities of the thin film in the (i+1)th segment and the i-th segment, respectively, in m / s; This refers to the film density, expressed in kg / m³. 3 The value is obtained from the material parameter table; for example, the value for PET film is 1380 kg / m³. 3 A represents the cross-sectional area of ​​the thin film, in meters. 2 The calculation formula is A = width × thickness, obtained through offline measurement; This is the wrap angle of the encoder corresponding to the roller, in rad. It is set according to the winding angle of the film on the roller, and the value range is usually [value range missing]. ; The pressure deviation of the i-th tension roller is expressed in N. The pressure-to-tension conversion efficiency is related to the friction coefficient of the tension roller material; the value is 0.85 for rubber rollers and 0.78 for metal rollers. When implementing dynamic error compensation, the ambient temperature w is collected by a temperature sensor installed near the encoder, and the elastic modulus E of the thin film is corrected. The relevant expression is: ;in, This is the standard elastic modulus at 25℃; When performing data verification, when the tension values ​​of two adjacent segments... and When the deviation exceeds the deviation threshold, which is 0.15, an anomaly flag is triggered, and backup encoder data is automatically activated; one backup unit is redundantly deployed for each encoder group.

[0022] In this embodiment of the invention, tension monitoring along the entire film transmission path is achieved through three sets of high-precision encoders, which can effectively improve spatial resolution and significantly enhance accuracy compared to traditional single-point detection. By integrating multi-dimensional data such as linear velocity difference, pressure deviation, and ambient temperature, tension calculation errors can be effectively controlled, solving the dynamic response lag problem caused by single velocity feedback. Through the implementation of a dynamic error compensation mechanism, the system maintains stable accuracy in environments ranging from -10℃ to 50℃, meeting the real-time control requirements of high-speed film cutting and improving the system's reliability and robustness.

[0023] The thin film segment dynamic operation control correction module acquires the tension deviation between the current tension value of each segment and the preset tension threshold, generates the target braking torque of the multi-segment magnetic powder brake assembly through a multi-segment coupled control algorithm, and dynamically allocates the braking torque according to the tension sensitivity coefficient of each segment. The braking torque allocation ratio between adjacent segments is corrected in real time through speed difference feedback. Specific steps include: Calculate the difference between the current tension value of each segment of the film and the preset tension threshold, and mark it as the tension deviation; Furthermore, based on the encoder position weights and film thickness, the tension sensitivity coefficient of each film segment is calculated. The expression involved is: ;in, The positional weights are set according to the importance of the film cutting process: 1.2 for the unwinding section, 1.5 for the traction section, and 1.0 for the rewinding section; d represents the film thickness in mm, obtained through offline measurement; L represents the distance between the encoder and the cutting blade in meters. The closer the distance, for example, 0.3 meters from the blade in the traction section, the smaller L is, resulting in a higher tension sensitivity coefficient. The larger the value, the more prioritized the tension adjustment in the cutting zone; When dynamically distributing braking torque based on the tension sensitivity coefficient, the obtained tension deviation will be processed. and tension sensitivity coefficient As input, the target braking torque is generated through a multi-segment coupled control algorithm. The expression involved is: ;in, The total reference braking torque is determined by the thin film linear velocity v, where v = 300 m / min. The value is 20 N·m, and the speed decreases by 50 m / min. Reduced by 15%; The sum of the products of sensitivity and deviation for each segment ensures torque distribution and and Positive correlation, meaning that more torque is obtained in the high sensitivity and large deviation range; For symbolic functions, When the value is greater than 0, the value is 1; otherwise, the value is -1, thus achieving closed-loop regulation that increases braking torque when there is over-tension and decreases braking torque when there is under-tension. By real-time correction of the torque distribution ratio between adjacent segments through speed difference feedback, the corrected braking torque is obtained. The correction formula is as follows: ;in, This is a speed difference feedback correction term; The difference in linear velocity between adjacent segments, if ,but Increase the braking torque of the i-th segment to reduce the speed difference and avoid excessive film stretching; This is the average speed across the entire path, used to normalize the speed difference and ensure consistent correction magnitudes across different linear velocities. Based on the target braking torque Speed ​​difference feedback correction term The final output braking torque And it is sent to the multi-segment magnetic powder brake assembly via the CAN bus, involving the following expression: .

[0024] In this embodiment of the invention, by coupling position weights and film thickness with the tension sensitivity coefficient, the torque adjustment accuracy of high-priority sections, such as the traction section, can be effectively improved, effectively solving the problem of local tension runaway caused by traditional uniform distribution. By introducing feedback correction of speed difference between adjacent sections, tension fluctuations are suppressed within ±1.2%, improving the adaptability to dynamic tension requirements of high-speed film cutting. Through threshold dynamic configuration and sensitivity coefficient formula, it can be compatible with film cutting scenarios of multiple materials such as PET, PE, and aluminum foil without changing hardware, realizing adaptive adjustment of films of different thicknesses.

[0025] The closed-loop control and adaptive adjustment module adjusts the excitation current of the magnetic powder brake assembly based on the generated final output braking torque. It also constructs a PID closed-loop control system using the tension feedback values ​​collected in real-time by the encoder assembly. When the tension fluctuation amplitude is less than or equal to the amplitude threshold for several consecutive sampling cycles, an adaptive integral separation mode is triggered to reduce overshoot. Specific steps include: Based on the generated final output braking torque The target excitation current of the magnetic powder brake is calculated using a current-torque conversion model. By outputting the target excitation current through the PWM controller, a precise mapping from braking torque to current is achieved. The relevant expression is as follows: ;in, This is the brake torque coefficient, measured in N·m / A, and is determined by the model of the magnetic powder brake. The brake temperature, in °C, is collected in real time by an NTC temperature sensor integrated into the brake housing. This is the no-load current, expressed in A, to ensure initial magnetization of the magnetic powder. The value range is 0.2~0.5A to avoid response lag at low torque. When constructing a PID closed-loop control using the tension feedback values ​​acquired in real time by the encoder group, the current tension value of the membrane is... As feedback input, it is compared with the preset process tension threshold. By comparison, a positional PID controller is constructed, and the output value of the PID controller for different sampling periods is calculated. The relevant expressions are as follows: ;in, It is the output value of the PID controller in the kth sampling period; For input error, k is the sampling period number; To correct the proportionality coefficient, and the tension sensitivity coefficient Positive correlation =0.8 Highly sensitive sections, such as traction sections. If the value is 1.51, then A value of 1.21 is used to enhance response speed; The integral coefficient is... , The system time constant is 0.1s. The differential coefficients are related to the average speed along the entire path. Positive correlation j is the index variable of the discrete-time sampling point; The PID controller output value calculated in the kth sampling period is sent to the PWM controller, which then... It is converted into excitation current and applied to the magnetic powder brake; When the tension fluctuation amplitude is ≤ ±M% for three consecutive sampling periods, M > 0, specifically a value of 1.5. The integral term is then enabled to eliminate steady-state error. Otherwise, keep the integral term at 0 to avoid integral saturation and overshoot; Specifically, when determining the tension fluctuation amplitude, the tension fluctuation amplitude of the k-th period is calculated. If three consecutive cycles If the value is ≤1.5%, the integral separation mode will be triggered; For example: setting tension =65N, for 3 consecutive cycles The values ​​are 64.2N, 65.5N, and 64.8N respectively; fluctuation range The values ​​are 1.23%, 0.77%, and 0.31%, respectively, all ≤1.5%, triggering integral separation; When adaptive adjustment of the integral term is enabled, the integral coefficient Follow input error Dynamic decay, the formula is: ;in, This is the baseline integration coefficient, with a default value of 0.5A / (N·s); This is the error threshold, with a default value of 2N. ≤ hour, Approaching ;when > hour, It decays rapidly to 0; When limiting and protecting the excitation current, a dynamic current upper limit is set to prevent the magnetic powder brake from overheating due to excessive current. : ;in, This is the rated current of the brake, with a default value of 5A. When the brake temperature When the temperature is above 40℃, the upper limit of the current decreases by 10% for every 5℃ increase, and the maximum current drops to 50% of the rated value to protect the life of the brake.

[0026] In this embodiment of the invention, the tension control accuracy can be effectively improved through PID closed-loop feedback, meeting the process requirements of precision film cutting; the adaptive integral separation mode enables integration when the tension fluctuation is ≤1.5%, which can significantly reduce overshoot and avoid film stretching deformation or wrinkling; the temperature-compensated current conversion model and dynamic current upper limit enable the system to work stably in different temperature environments, enhancing the adaptability of the working conditions; by combining the sampling period with the current adjustment delay, the response time of tension mutation is ensured to be controlled within the standard reaction time, avoiding the risk of film breakage.

[0027] In the several embodiments provided by this invention, it should be understood that the disclosed system can be implemented in other ways. For example, the embodiments of the invention described above are merely illustrative; for example, the division of modules is only a logical functional division, and there may be other division methods in actual implementation.

[0028] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical modules; they may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0029] Furthermore, the functional modules in the various embodiments of the present invention can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module. The integrated module can be implemented in hardware or in the form of hardware plus software functional modules.

[0030] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the essential characteristics of the present invention.

[0031] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A computer-based membrane cutting production application management system, characterized in that, include: The film segment monitoring data processing module collects real-time operating parameters of each segment of the film through a high-resolution encoder group distributed along the film transport path, calculates the current tension value of each segment of the film, and performs dynamic error compensation and data verification; the operating parameters include film linear velocity, roller angular displacement and tension roller pressure deviation; Thin film segment dynamic operation control correction module: obtains the tension deviation between the current tension value of each thin film segment and the preset tension threshold, generates the target braking torque of the multi-segment magnetic powder brake group through the multi-segment coupling control algorithm, and dynamically allocates the braking torque according to the tension sensitivity coefficient of each segment. The braking torque allocation ratio of adjacent segments is corrected in real time through speed difference feedback. Closed-loop control and adaptive adjustment module: Based on the generated final output braking torque, the excitation current of the magnetic powder brake group is adjusted, and PID closed-loop control is constructed through the tension feedback value collected in real time by the encoder group. When the tension fluctuation amplitude is less than or equal to the amplitude threshold for several consecutive sampling cycles, the adaptive integral separation mode is triggered to reduce the overshoot.

2. The computer-based film cutting production application management system according to claim 1, characterized in that, Based on the collected data, including roller angular displacement θ, film linear velocity v, and tension roller pressure deviation ΔP, the current tension value of each film segment is calculated using a formula. The expression involved is: ;in, This is the position correction factor; These are the linear velocities of the thin film in the (i+1)th segment and the i-th segment, respectively; Where A is the film density; A is the cross-sectional area of ​​the film. This is the wrap angle of the encoder corresponding to the roller; The deviation of the tension roller pressure in the i-th segment; This refers to the pressure-to-tension conversion efficiency.

3. The computer-based film cutting production application management system according to claim 2, characterized in that, When implementing dynamic error compensation, the ambient temperature w is collected by a temperature sensor installed near the encoder, and the elastic modulus E of the thin film is corrected. The relevant expression is: ;in, This is the standard elastic modulus at 25℃.

4. The computer-based film cutting production application management system according to claim 3, characterized in that, When performing data verification, when the tension values ​​of two adjacent segments... and When the deviation exceeds the deviation threshold, an anomaly flag is triggered, and backup encoder data is automatically activated.

5. The computer-based film cutting production application management system according to claim 4, characterized in that, Based on the encoder position weight and film thickness, the tension sensitivity coefficient of each film segment is calculated. When dynamically allocating braking torque based on the tension sensitivity coefficient, the obtained tension deviation and tension sensitivity coefficient are used as inputs, and the target braking torque is generated through a multi-segment coupling control algorithm.

6. The computer-based film cutting production application management system according to claim 5, characterized in that, The torque distribution ratio between adjacent segments is corrected in real time by speed difference feedback to obtain the corrected braking torque; based on the target braking torque and the speed difference feedback correction term, the final output braking torque is output and sent to the multi-segment magnetic powder brake assembly via CAN bus.

7. The computer-based film cutting production application management system according to claim 6, characterized in that, Based on the generated final output braking torque, the target excitation current of the magnetic powder brake is calculated through a current-torque conversion model, and the target excitation current is output through a PWM controller to achieve a precise mapping from braking torque to current.

8. The computer-based film cutting production application management system according to claim 7, characterized in that, When constructing a PID closed-loop control by acquiring tension feedback values ​​in real time using the encoder group, the current tension value of the film is used as the feedback input and compared with the preset process tension threshold to construct a position-type PID controller and calculate the PID controller output value for different sampling periods. The PID controller output value calculated in the kth sampling period is sent to the PWM controller, which then converts the PID controller output value into an excitation current and applies it to the magnetic powder brake.

9. The computer-based film cutting production application management system according to claim 8, characterized in that, When the tension fluctuation amplitude is ≤ ±M% for three consecutive sampling periods, M > 0, and the integral term is enabled to eliminate steady-state error; otherwise, the integral term is kept at 0 to avoid overshoot caused by integral saturation.

10. A computer-based membrane cutting production application management system according to claim 9, characterized in that, The integral term is ;in, The integral coefficient; This is for input error; is the sampling period time interval; k is the sampling period number; j is the index variable of the discrete-time sampling point.

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