A multi-stage regulation method for lateral deviation of ultra-thin film in roll-to-roll system

Abstract

This invention belongs to the technical field of precision roll-to-roll manufacturing, specifically relating to a multi-level control method for the lateral sway of an ultrathin film in a roll-to-roll system. The method includes: setting up multi-level lateral correction units arranged sequentially along the running direction of the ultrathin film strip on the roll-to-roll system; real-time acquisition of lateral sway data at each level; and executing multi-level control of the ultrathin film lateral sway. The structure and control parameters of the fine-tuning correction unit satisfy the following: correcting the lateral position of the strip relative to the target position with a preset small stroke amplitude sway component; the structure and control parameters of the coarse-tuning correction unit satisfy the following: correcting the lateral position of the strip relative to the target position with a preset large stroke amplitude sway component; the lower limit of the small stroke amplitude is less than the target processing range, and the upper limit of the small stroke amplitude is greater than the lower limit of the large stroke amplitude. This invention can improve the processing accuracy of the processing area in the roll-to-roll manufacturing system, ensuring the overall stability of the system and the quality of the finished product.

Description

Technical Field

[0001] This invention belongs to the technical field of precision roll-to-roll manufacturing, and more specifically, relates to a multi-level control method for the lateral sway of ultrathin films in roll-to-roll systems. Background Technology

[0002] In roll-to-roll systems, flexible film material sequentially passes through the unwinding mechanism, guide roller system, processing unit, and winding mechanism, achieving stable transmission under the action of a tension control system. During operation, the belt must maintain not only stable longitudinal tension but also stable lateral position to ensure material edge alignment and winding end-face quality. However, in practical engineering applications, due to the combined effects of roller system installation errors, axis parallelism deviations, guide roller roundness errors, tension fluctuations caused by changes in unwinding and winding diameters, and uneven distribution of the material's thickness and elastic modulus, the belt is prone to lateral swaying in the width direction. This lateral swaying becomes more pronounced when the equipment is starting, stopping, accelerating, decelerating, or subjected to external vibration disturbances. If lateral swaying is not effectively suppressed, it will lead to material edge misalignment, winding end-face lamination shift, and even wrinkles or breakage defects due to lateral stress concentration, thus seriously affecting product quality.

[0003] Existing roll-to-roll manufacturing equipment typically employs a single-stage lateral correction structure. This structure uses edge detection sensors to acquire real-time strip position deviation signals and drives the actuator to laterally move the guide rollers for closed-loop compensation. This structure can achieve low-speed centering control under conditions of conventional thickness materials and medium tension operation. However, when processing flexible ultrathin films with thicknesses in the micrometer range, the system's operating physical characteristics change significantly. For a given width and thickness... h The bending stiffness per unit width of the strip can be expressed as: ,in E The elastic modulus of the material. ν Here, is Poisson's ratio. From the above relationship, it can be seen that the bending stiffness is directly proportional to the cube of the film thickness. When the film thickness decreases to the micrometer level, its transverse bending stiffness decreases by an order of magnitude, and the material's inherent resistance to transverse disturbances is significantly weakened. During roll-to-roll transport, the equivalent transverse stability of the belt can be approximated as the combined effect of the tension term and the bending stiffness term, i.e.: ,in T The tension term represents the belt tension. When the film thickness is extremely thin, the bending stiffness term decreases significantly relative to the tension term, and the lateral stability of the system mainly depends on the tension. However, to avoid plastic deformation, necking, or fracture of the ultrathin film material during operation, micro-tension control must be used in practical engineering to keep the belt under low tensile stress. At this point, the tension term... TSimilarly, the range is relatively small, resulting in an overall decrease in the lateral equivalent stiffness and a significant increase in the system's sensitivity to lateral disturbances. Under these physical conditions, the lateral motion of the belt exhibits low damping and high sensitivity characteristics; even minor disturbances can trigger significant drift. Furthermore, frequent or large-amplitude movements of the actuator can easily couple with the tension adjustment system, thereby amplifying system oscillations.

[0004] Under the aforementioned operating conditions, single-stage web guiding systems face a structural contradiction between balancing stroke and accuracy. When the system is designed with a large stroke to accommodate larger initial deviations or installation errors, the stiffness of the mechanism and the control response speed often decrease, making it difficult to achieve precise compensation for small deviations. When the control gain is increased to improve the positioning accuracy in the small deviation stage, it is easy to induce oscillations or even tension disturbance superposition effects under micro-tension conditions. At the same time, in the winding stage where the roll diameter gradually increases, any tiny lateral residual error will be amplified with the accumulation of layers, resulting in obvious step differences on the winding end face. Therefore, single-stage lateral web guiding structures in micron-scale flexible ultrathin film roll-to-roll systems cannot simultaneously achieve a balance between large deviation suppression capability, small deviation high-precision control capability, and system operational stability, nor can they guarantee the flatness quality of the final winding end face.

[0005] Therefore, the field urgently needs a new lateral correction scheme to improve the overall stability and finished product quality of roll-to-roll manufacturing systems. Summary of the Invention

[0006] To address the aforementioned deficiencies or improvement needs of existing technologies, this invention provides a high-precision roll-to-roll system ultrathin film lateral sway multi-level control method, the purpose of which is to improve the processing accuracy of the processing area in the roll-to-roll manufacturing system, and ensure the overall stability of the system and the quality of the finished product.

[0007] To achieve the above objectives, according to one aspect of the present invention, a method for multi-level control of lateral yaw in a roll-to-roll system ultrathin film is provided, comprising: A multi-level lateral correction unit is set up on the roll-to-roll system along the running direction of the ultra-thin film belt: a coarse adjustment lateral correction unit is set at the front end of the belt running path including the unwinding end and its preset range, a fine adjustment lateral correction unit is set in the roll-to-roll processing area, and a re-inspection lateral correction unit is set at the front end of the winding before the belt enters the winding mechanism. The system collects lateral sway data in real time at the front end of the path, the roll-to-roll processing area, and the front end of the take-up, including the lateral position, speed, and tension of the belt. It calculates the difference between the lateral position and the target position at each collection point. Based on the change of the difference over time, and combined with the real-time belt tension and speed collected at the corresponding positions, it determines the control parameters of the corresponding correction units at each level, and performs multi-level control of the ultra-thin film lateral sway. Through closed-loop control, the belt sway is finally controlled within the target processing range. The fine-tuning lateral correction unit's structure and control parameters satisfy the following: it corrects the belt's lateral position relative to the target position by a preset small stroke amplitude oscillation component; the coarse-tuning lateral correction unit's structure and control parameters satisfy the following: it corrects the belt's lateral position relative to the target position by a preset large stroke amplitude oscillation component; the re-inspection lateral correction unit's structure and control parameters satisfy the following: it compensates for and corrects the belt's residual lateral sway relative to the target position before winding; the lower limit of the small stroke amplitude is less than the target processing range, and the upper limit of the small stroke amplitude is greater than the lower limit of the large stroke amplitude.

[0008] Furthermore, the correction accuracy of each level of lateral correction unit is quantitatively characterized by the steady-state deviation or peak-to-peak error of the lateral position of the belt relative to the target position.

[0009] Furthermore, under the condition that the ultrathin film operates within the preset micro-tension control range, the control parameters of each level of the lateral correction unit also satisfy the following: the sum of the external disturbance force and the lateral correction force applied to the belt corresponding to the control parameters is less than the product of the preset tension per unit width of the thin film material and the proportional coefficient corresponding to the preset correction unit structural parameters, wherein the proportional coefficients corresponding to different levels of the lateral correction unit are different.

[0010] Furthermore, the coarse adjustment lateral correction unit is configured to include a first laser displacement sensor and at least one actuator with lateral adjustment capability. The actuator is a servo screw slide or a pneumatic proportional actuator structure. By driving the lateral movement of the platform assembly used to support the roll-to-roll structure, the deviation of the lateral position of the tape at the acquisition position relative to the target position is coarsely adjusted.

[0011] Furthermore, the fine-tuning lateral correction unit is configured to include a second laser displacement sensor and an actuator with lateral adjustment capability that works in conjunction with it. The second laser displacement sensor has a higher accuracy than the first laser displacement sensor. The actuator that works in conjunction with the second laser displacement sensor is a servo linear motor or a piezoelectric actuator. By driving the processing station, the target position is changed, thereby achieving fine-tuning of the deviation between the lateral position of the belt at the acquisition position and the target position.

[0012] Furthermore, the correction accuracy of the fine-tuning lateral correction unit is the same as that of the coarse-tuning lateral correction unit. k times, k >1; k The value range satisfies the following: the coarse adjustment lateral correction unit compresses the lateral sway amplitude of the belt to within the working range of the preset stabilization processing of the fine adjustment lateral correction unit, and the tolerance of the coarse adjustment lateral correction unit to disturbances in the belt's running tension during execution is higher than the corresponding disturbance tolerance of the fine adjustment lateral correction unit; and kThe specific value is determined comprehensively based on the stability requirements of the belt offset position in different regions, processing tolerance, and cost control.

[0013] Furthermore, the determination of the control parameters for the re-inspection lateral correction unit is achieved as follows: The deviation of the belt's lateral position relative to the target position at the sampling location in the re-inspection lateral correction unit based on real-time data acquisition. Calculate the amount of tape wound on the take-up shaft. n The cumulative deviation of the layer is expressed as: When the cumulative deviation exceeds the preset threshold, the control parameters of the re-inspection lateral correction unit are determined based on the cumulative deviation and the belt tension and belt speed collected in real time in the re-inspection lateral correction unit.

[0014] Furthermore, lateral sway data are collected at locations with relatively small tension fluctuations, such as the front end of the path, the roll-to-roll processing area, and the front end of the winding.

[0015] According to another aspect of the present invention, a roll-to-roll system ultrathin film lateral sway multi-level control device is provided, characterized in that it is used to execute the roll-to-roll system ultrathin film lateral sway multi-level control method as described above, comprising: a coarse adjustment lateral correction unit disposed on the belt running path including the unwinding end and the path front end within a preset range; a fine adjustment lateral correction unit disposed on the roll-to-roll processing area of ​​the belt running path; a re-inspection lateral correction unit disposed on the winding front end before the belt enters the winding mechanism; and a control module; The control module is used to collect lateral sway data in real time at the front end of the path, the roll-to-roll processing area, and the front end of the winding through the lateral correction units at each level; and to coordinately adjust the control parameters of the lateral correction units at each level in conjunction with the real-time collected belt tension.

[0016] In summary, compared with the prior art, the technical solutions conceived by this invention have the following main advantages: 1. This invention proposes a multi-level control method for the lateral sway of an ultrathin film in a roll-to-roll system. This method acquires lateral position data of the tape during roll-to-roll operation, including sway data at the coarse adjustment lateral correction unit, sway data at the fine adjustment lateral correction unit in the roll-to-roll processing area, and residual lateral sway data in the re-inspection area. The method integrates and analyzes the temporal data of the preceding detection, the core area detection, and the final residual sway data to calculate the amplitude and trend of the tape's lateral sway. Based on preset micro-tension control conditions and a three-level correction control method, corresponding correction control parameters are generated. This invention addresses the characteristics of micron-scale ultrathin films under micro-tension conditions, which are sensitive to lateral disturbances and have limited space for applying correction forces. It employs a multi-stage lateral sway control method for phased correction control of the belt. Specifically, by setting up multiple stages of lateral correction units arranged sequentially along the belt's running direction, the first-stage correction unit performs initial correction of the low-frequency components of the belt's lateral sway over a large stroke range without significantly disturbing the belt's tension distribution, thus compressing the lateral sway amplitude. After the first-stage correction, when a section of the belt moves to the processing area, the subsequent fine-tuning correction unit performs high-precision, small-amplitude correction control on this section based on the previous correction. In the re-inspection area, incomplete corrections or additional sway are compensated and corrected, thereby achieving gradual attenuation and stable control of the lateral sway of each part of the belt along the running direction under micro-tension conditions. This invention achieves pre-stage suppression of installation errors and slow drift, precise compensation of dynamic deviations, and final inspection and correction of the winding end face by rationally dividing the work of different levels in terms of stroke range, control precision, and response frequency. It meets the sway tolerance required for processing, improves the processing precision of the processing area in the roll-to-roll manufacturing system, and ensures the overall stability of the system and the quality of the finished product. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of a multi-level control device for lateral sway of an ultrathin film in a roll-to-roll system, provided in an embodiment of the present invention. Figure 2 This is a schematic diagram of the multi-level control function zoning of the ultrathin film lateral yaw provided in an embodiment of the present invention; Figure 3 This is an exploded view of the lateral deviation of the belt position provided in an embodiment of the present invention; Figure 4 This is a schematic diagram illustrating the principle of lateral adjustment of the belt position provided in an embodiment of the present invention.

[0018] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein: 1 is PC, 2 is PLC, 3 is laser displacement sensor, 4 is front-end correction linear motor, 5 is high-precision laser displacement sensor, 6 is working area correction linear motor, 7 is high-precision vision camera, 8 is take-up end correction linear motor, 9 is front-end correction module, 10 is unwinding module, 11 is flexible ultra-thin film belt, 12 is working area correction module, 13 is drive roller, 14 is take-up module, and 15 is take-up end correction module. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0020] Example 1 A method for multi-level control of lateral yaw in a roll-to-roll system ultrathin film includes: A multi-level lateral correction unit is set up on the roll-to-roll system along the running direction of the ultra-thin film belt: a coarse adjustment lateral correction unit is set at the front end of the belt running path including the unwinding end and its preset range, a fine adjustment lateral correction unit is set in the roll-to-roll processing area, and a re-inspection lateral correction unit is set at the front end of the winding before the belt enters the winding mechanism. The system collects lateral sway data in real time at the front end of the path, the roll-to-roll processing area, and the front end of the take-up, including the lateral position, speed, and tension of the belt. It calculates the difference between the lateral position and the target position at each collection point. Based on the change of the difference over time, and combined with the real-time belt tension and speed collected at the corresponding positions, it determines the control parameters of the corresponding correction units at each level, and performs multi-level control of the ultra-thin film lateral sway. Through closed-loop control, the belt sway is finally controlled within the target processing range. The fine-tuning lateral correction unit's structure and control parameters satisfy the following: it corrects the belt's lateral position relative to the target position by a preset small stroke amplitude oscillation component; the coarse-tuning lateral correction unit's structure and control parameters satisfy the following: it corrects the belt's lateral position relative to the target position by a preset large stroke amplitude oscillation component; the re-inspection lateral correction unit's structure and control parameters satisfy the following: it compensates for and corrects the belt's residual lateral sway relative to the target position before winding; the lower limit of the small stroke amplitude is less than the target processing range, and the upper limit of the small stroke amplitude is greater than the lower limit of the large stroke amplitude.

[0021] In this embodiment, the lateral position data of the belt during the roll-to-roll process is acquired, including the sway data obtained by the lateral displacement detection unit in the coarse adjustment lateral correction unit, the sway data obtained by the lateral displacement detection unit in the roll-to-roll processing area, and the residual lateral sway data obtained by the re-inspection area. The preceding detection data, core area detection data, and final residual sway data are integrated and trend analyzed over time to calculate the lateral sway amplitude and trend of the belt. Corresponding correction control parameters are generated based on preset micro-tension control conditions and a three-level correction control method. The entire process of lateral sway data, correction actions, and motor response curves are recorded. Control commands are sent to the preceding lateral correction actuator, the subsequent high-precision lateral correction actuator, and the take-up end compensation actuator according to multi-level collaborative control rules to adjust system process parameters, forming a multi-level lateral sway closed-loop control loop. The execution module adjusts the lateral position to achieve graded correction and active end compensation of the belt's lateral sway, ensuring the belt's operational stability and the neatness and straightness of the take-up end face.

[0022] It should be noted that before implementing the lateral yaw control method, initial strip parameters for the flexible ultrathin film to be transported are set. These initial parameters include the ultrathin film thickness, elastic modulus, and allowable strain range. The thickness of the flexible ultrathin film is in the micrometer range. Due to the significantly reduced thickness, the effective load-bearing cross-sectional area of ​​the strip is greatly reduced, significantly limiting its ability to bear longitudinal tensile loads during roll-to-roll operation. Based on the micrometer-level film thickness condition, combined with the elastic modulus and allowable strain range of the ultrathin film material, the upper limit of the allowable safe tension of the strip during operation is determined. The actual operating tension of the strip during roll-to-roll operation is then limited to a micro-tension control range below this upper limit, achieving micro-tension control of the ultrathin film. The upper limit of safe tension is calculated using the tension per unit width and is related to parameters such as the tension per unit width, the elastic modulus of the ultrathin film material, the film thickness, and allowable engineering strain. Under the condition that the elastic modulus and allowable strain range are determined, the upper limit of tension per unit width is linearly positively correlated with the film thickness. The micrometer-level film thickness reduces the upper limit of safe tension to the micro-tension level, thus requiring micro-tension control during roll-to-roll operation.

[0023] As a preferred embodiment, under the condition that the ultrathin film operates within a preset micro-tension control range, the lateral correction force applied to the belt is constrained by the longitudinal tension of the material belt, and the control parameters of each level of the lateral correction unit also satisfy the following: the sum of the external disturbance force and the lateral correction force applied to the belt corresponding to the control parameters is less than the product of the preset tension per unit width of the thin film material and the proportional coefficient corresponding to the preset correction unit structural parameters, wherein the proportional coefficients corresponding to different levels of the lateral correction unit are different.

[0024] To address the sensitivity of micron-scale ultrathin films to lateral disturbances and the limited space for applying corrective forces under micro-tension conditions, a multi-stage lateral sway control method is employed for phased correction control of the tape. Specifically, by setting up multiple stages of lateral correction units arranged sequentially along the tape's running direction, the first-stage correction unit performs initial correction of the tape's lateral sway over a large stroke range with low-frequency components without significantly disturbing the tape's tension distribution, thus compressing the lateral sway amplitude. After the first-stage correction, when a segment of the tape moves to the processing area, the subsequent correction unit, based on the previous stage correction, implements high-frequency, high-precision, small-amplitude continuous correction control on this segment as it enters the core working area. This achieves gradual attenuation and stable control of the lateral sway of each part of the tape along the running direction under micro-tension conditions, making it particularly suitable for lateral stability control and end-face quality adjustment of tension-sensitive flexible ultrathin films during roll-to-roll operations.

[0025] In the multi-stage lateral sway control method, the pre-stage lateral correction unit is set at the front of the belt running path. It is used to eliminate and suppress the lateral position deviation introduced by equipment installation error, initial alignment deviation and tension establishment process before the belt enters the core working area. Preferably, the pre-stage lateral correction unit includes at least one actuator with lateral adjustment capability. The actuator is a servo screw slide or a pneumatic proportional actuator structure. By driving the lateral movement of the platform component used to support the roll-to-roll structure, the deviation of the belt's lateral position relative to the target position at the acquisition position is coarsely adjusted. The control method, based on the belt edge position information acquired by the front-end laser displacement detection unit, drives the front-stage lateral correction unit to perform low-frequency, large-amplitude initial adjustments to the belt's lateral position to suppress lateral drift during the initial operation of the belt and compensate for system installation errors. The front-stage lateral correction unit, with its relatively large lateral adjustment stroke and relatively low control precision, is preferred. The correction precision of each stage of the lateral correction unit is quantified using the steady-state deviation or peak error of the belt's lateral position relative to the target position. In this method, as a preferred implementation, the correction precision of the fine-tuning lateral correction unit is higher than that of the coarse-tuning lateral correction unit. k times, k >1; k The value range satisfies the following: the coarse adjustment lateral correction unit compresses the lateral sway amplitude of the belt to within the working range of the preset stabilization processing of the fine adjustment lateral correction unit, and the tolerance of the coarse adjustment lateral correction unit to disturbances in the belt's running tension during execution is higher than the corresponding disturbance tolerance of the fine adjustment lateral correction unit; and k The specific value is determined comprehensively based on the stability requirements of the belt offset position in different regions, processing tolerance, and cost control.

[0026] Based on the fact that the lateral sway amplitude of the belt is compressed to the range that the subsequent stage can handle by the pre-stage lateral correction unit, a high-precision lateral correction control unit is set in the core working area of ​​the belt's running path. Compared with the pre-stage correction area, the correction error of the working area is set to 1 / k (k>1) of the pre-stage correction area. Preferably, the subsequent high-precision lateral correction unit includes a high-precision laser displacement sensor and a high-response actuator that works in conjunction with it. The actuator is a servo linear motor or a piezoelectric actuator, which drives the processing station to change the target position, thereby achieving fine adjustment of the deviation of the belt's lateral position relative to the target position at the acquisition position. The high-precision laser displacement sensor is used to detect the lateral position of the belt in the core working area in real time to obtain the instantaneous offset of the lateral sway.

[0027] Before the tape enters the winding mechanism, a re-inspection area is set up at the front end of the winding. A high-precision vision camera arranged in the re-inspection area detects the lateral position of the tape in real time and obtains the residual lateral sway of the tape before winding. The winding end correction execution mechanism includes a winding platform with lateral adjustment capability and a linear motor. Based on the residual lateral sway data, the linear motor is driven to actively compensate and adjust the lateral position of the winding platform to correct the lateral alignment state of the tape during the winding stage. Through the final re-inspection and active compensation process, the tape maintains a stable lateral position during the winding process, thereby improving the end face flatness of the winding core and ensuring the end face quality of the final wound product.

[0028] In a preferred embodiment, the control parameters for the re-inspection lateral correction unit are determined as follows: based on the deviation of the lateral position of the belt at the sampling position in the re-inspection lateral correction unit relative to the target position, which is collected in real time. Calculate the amount of tape wound on the take-up shaft. n The cumulative deviation of the layer is expressed as: When the cumulative deviation exceeds the preset threshold, the control parameters of the re-inspection lateral correction unit are determined based on the cumulative deviation and the belt tension and belt speed collected in real time in the re-inspection lateral correction unit.

[0029] The central control unit collects and manages the lateral slip data, correction execution commands, and actuator response information of the tape body acquired during operation by the front-stage lateral slip data unit, the rear-stage high-precision lateral slip data unit, and the final inspection and winding-end correction unit. Based on the temporal variation characteristics of the multi-stage lateral slip data, the control parameters of each lateral slip control unit are adjusted in a coordinated manner to achieve dynamic matching and stable coordination between the multi-stage lateral slip units. Through a closed-loop control method for the entire process, the stability of lateral slip and the consistency of winding quality are improved under different operating speeds, different film parameters, and external disturbances.

[0030] Example 2 A roll-to-roll system ultrathin film lateral sway multi-level control device is used to execute a roll-to-roll system ultrathin film lateral sway multi-level control method as described in Embodiment 1, comprising: a coarse adjustment lateral correction unit disposed on the front end of the path including the unwinding end and the path front end within a preset range of the belt running path; a fine adjustment lateral correction unit disposed on the roll-to-roll processing area of ​​the belt running path; a re-inspection lateral correction unit disposed on the front end of the winding mechanism before the belt enters the winding mechanism; and a control module; The control module is used to collect lateral sway data in real time at the front end of the path, the roll-to-roll processing area, and the front end of the winding through the lateral correction units at each level; and to coordinately adjust the control parameters of the lateral correction units at each level in conjunction with the real-time collected belt tension.

[0031] To better illustrate Embodiment 1 and Embodiment 2, the following examples are provided: like Figure 1 As shown, the system consists of PC1, PLC2, laser displacement sensor 3, front-stage correction linear motor 4, high-precision laser displacement sensor 5, working area correction linear motor 6, high-precision vision camera 7, take-up end correction linear motor 8, front-stage correction module 9 (containing the correction object), unwinding module 10, flexible ultra-thin film belt 11, working area correction module 12, drive roller 13, take-up module 14, and take-up end correction module 15. During operation, the belt speed is relatively high, and the motor's accuracy and response speed cannot match, resulting in a lag between correction and detection. To achieve high-precision correction under rapid transport, the belt stroke needs to be increased; therefore, the front-stage correction module 9 contains a large number of belt rollers.

[0032] like Figure 2 As shown, a multi-level hierarchical lateral yaw control system is provided, which is divided into a pre-stage coarse adjustment correction zone, a working fine adjustment correction zone, and a re-inspection correction zone according to the belt running direction. Each zone interacts with signals and coordinates control through a central control system. Different subscripts are shown in the figure. Y Functions representing the lateral position of the volume at different locations, with different subscripts. u This represents the control input quantity of the correction actuator in the corresponding correction unit, with different subscripts. T This indicates the belt tension control parameters for the corresponding reel. Figure 2 In this system, the PLC is used to issue execution commands to the motor, while the PC is used to process the lateral position deviation value of the sampled position and compensate for the time and distance of the belt from the sampled position to the actuator, and calculate the actual deviation value at the coordinate of the actuator.

[0033] During operation, the lateral position of the thin film at a certain detection section (sampling location) of the belt... y It can be represented as a time function Relative to the target reference position The deviation is defined as:

[0034] Based on actual engineering test results, the lateral deviation value includes the lateral drift of yaw components at different frequencies, which can be expressed as follows according to the frequency domain:

[0035] Among them, the low-frequency deviation component The main sources of these deviations are low-frequency disturbances such as equipment structure installation errors, roller axis parallelism errors, initial belt alignment deviations, and slow drift during operation. These deviations accumulate and persist throughout the entire belt's running path. While their rate of change is relatively slow, their amplitude is relatively large. Therefore, it is preferable to perform pre-compensation and suppression of large-stroke, low-frequency responses in the preceding coarse adjustment correction zone to reduce the lateral sway amplitude transmitted to the subsequent core working area. In other words, the large stroke amplitude must cover these low-frequency deviation components.

[0036] High-frequency deviation components The main sources are tension fluctuations, equipment vibrations, dynamic operational disturbances, and transient lateral disturbances generated during high-speed conveying. These deviations are characterized by high frequency of change, small amplitude, but high real-time requirements. Therefore, the working fine-tuning and correction zone uses a short-stroke, high-response, and high-precision actuator for real-time dynamic compensation to improve the stability of the belt's lateral position within the core working area. In other words, the short-stroke amplitude must cover these high-frequency deviation components.

[0037] like Figure 3 As shown, the position deviation of the yaw components in different frequency bands is controlled separately by partitioning and grading. After the lateral error signal is divided into frequency domains, it is processed by the pre-stage coarse adjustment correction zone and the working fine adjustment correction zone respectively. The re-inspection correction zone completes the adjustment of the residual error of the lateral yaw (including the error not adjusted in the first two stages and the newly generated error).

[0038] like Figure 4 As shown, the horizontal correction actuator is driven by a linear motor to move horizontally, changing the belt entry angle or the real-time centerline of the belt, thereby achieving the overall offset of the belt.

[0039] After the tape is led out from the unwinding end, it first enters the pre-stage coarse adjustment and correction area. A laser displacement sensor, a linear motor, and the pre-stage correction mechanism are installed in this area. The laser displacement sensor is used to detect the positional deviation signal of the tape edge relative to the system reference centerline (the preset target tape centerline) in real time, obtaining the first deviation signal. The control system (PC+PLC) uses the PID control law:

[0040] The output adjustment is sent to the preceding lateral correction actuator, causing the overall running center of the belt to shift. The control parameters for the pre-stage coarse adjustment and correction are specifically adjusted adaptively by the control system through closed-loop logic. The lateral correction actuator preferably employs a servo screw slide or pneumatic proportional actuator structure. Such mechanisms offer a large lateral adjustment stroke, high structural rigidity, and good low-speed operational stability. By driving the lateral movement of the platform components supporting the roll-to-roll structure, they achieve coarse adjustment of the deviation between the lateral position of the tape at the acquisition location and the target position. The lateral adjustment stroke of this type of mechanism is set to a range of ±5mm to ±20mm to eliminate equipment installation errors, initial alignment (lateral) errors, and low-frequency slow lateral drift. Since this stage primarily absorbs large deviations, its correction accuracy is preferably controlled within the range of ±10μm to ±100μm, and the control bandwidth is set to a low-frequency response mode to avoid system coupling oscillations caused by excessively high control gain under micro-tension operating conditions. After pre-stage adjustment, the tape enters a relatively stable tension zone (working correction zone), thus providing a smaller amplitude input condition for subsequent precision compensation.

[0041] The belt enters the fine-tuning and correction area. A high-precision laser displacement sensor and a high-response execution platform are installed in this area to achieve sub-micron level detection and resolution. The detection area is preferably located in a stable region with minimal tension fluctuations to reduce the impact of tension disturbances on the measurement results. After the belt enters, the system acquires a high-precision deviation signal. Under micro-tension conditions, the transverse dynamic behavior of the belt can be approximated as a second-order system: ,in, This indicates the lateral displacement of the belt relative to the target centerline; Indicates lateral velocity; Indicates lateral acceleration; M The equivalent inertial parameter representing the lateral motion of the belt; C This represents the system's equivalent damping coefficient; K This indicates the equivalent lateral stiffness of the belt. This indicates the lateral control force and external disturbance force applied by the correction actuator. M, C, K The equivalent parameters are obtained by fitting the control system.

[0042] The control law of the control system in the fine-tuning zone can be expressed as:

[0043] The output adjustment is sent to the lateral correction actuator in the working area, causing the overall center of the belt to shift. is the control parameter for pre-stage coarse alignment correction, and its specific value is adaptively adjusted by the control system; the deviation correction actuator in the working area supporting the precision detection system preferably adopts a high-rigidity linear motor drive platform or a precision ball guide slide table structure. Such structures have the characteristics of a short transmission chain, no backlash, and a high dynamic response speed. The effective lateral adjustment stroke is preferably set within the range of ±1 mm to ±5 mm, and the deviation correction accuracy is preferably controlled within the range of ±1 μm to ±10 μm, so as to be controlled within the preset processing tolerance range, specifically for fine dynamic compensation of the residual small deviation and high-frequency disturbance after the pre-stage coarse alignment correction. This working fine alignment correction unit constructs a real-time closed-loop adjustment mechanism based on lateral position feedback. The high-precision laser displacement sensor detects the lateral deviation of the strip in real time. The control system generates a dynamic compensation command according to the detection result and drives the high-response actuator for position adjustment, thereby realizing continuous closed-loop correction of the lateral yaw of the strip. Through the collaborative design of stroke reduction and response bandwidth improvement of high-frequency components, this stage can achieve micron-level stable compensation in a micro-tension and low-damping environment, while avoiding the transmission of high-frequency adjustment signals to the pre-stage structure or the tension control system, thus forming frequency decoupling.

[0044] Before the strip enters the winding area, a re-inspection alignment correction area is set. This area includes a high-precision vision re-inspection device and a winding-end alignment correction mechanism, which are used to detect and correct the final lateral position of the strip. The re-inspection data (i.e., the real-time lateral residual yaw ) is transmitted to the control system. The cumulative error of the n th layer of winding can be expressed as: . When the cumulative error exceeds the preset threshold, the winding platform performs compensation adjustment through the lateral alignment correction mechanism.

[0045] The vision detection system in the re-inspection area obtains the residual lateral deviation of the strip before it enters the winding area in real time and transmits the deviation data to the central control system. The central control system calculates the cumulative lateral offset of the strip during the winding process based on the continuously collected residual lateral deviation data, and generates a lateral compensation command for the winding end according to the cumulative lateral offset, driving the winding platform or the guiding mechanism for low-frequency, progressive lateral position adjustment, so that the center line of the core gradually tracks the actual running center line of the strip, realizing the dynamic alignment of the center line of the core and the actual running center line of the strip, and ensuring . Since the winding diameter increases layer by layer during the winding process, the lateral residual error has an interlayer cumulative effect. Therefore, this final stage unit mainly undertakes the functions of error cumulative suppression and end face quality optimization, and its actions are usually carried out under low-frequency or threshold trigger conditions to avoid interfering with the pre-stage dynamic control.

[0046] In the specific implementation of the method, the first step is system startup and initialization: the control system is started and initialized, zero-position calibration is completed, correction parameters are set, and the unwinding mechanism is driven to release the flexible ultra-thin film. After the roll-to-roll system stabilizes, the control method of Example 1 is executed. Specifically, the unwinding mechanism releases the flexible ultra-thin film under the drive of the drive motor. The laser displacement detection unit collects the edge position data of the tape and transmits it to the control module. Based on the displacement parameters, the system determines the initial sway data of the ultra-thin film and drives the active roller motor and the linear motor of the unwinding platform to control tension and lateral sway, performing preliminary correction of the lateral position. For the same section of tape, when the tape reaches the core working area, the high-precision laser displacement sensor obtains the real-time lateral sway value. The central control system combines the preceding and following data information to perform multi-point fitting, determines the sway trend, and controls the actuator to complete the core working area. Real-time tape correction action; a high-precision vision camera is located in the pre-winding inspection area to accurately detect the lateral position of the same tape segment before winding. If residual sway still exists, the control system adjusts the linear motor at the winding end to control the correction mechanism for active compensation, forming a closed-loop control circuit. The winding mechanism completes the tape winding process under motor drive. The control system records the lateral sway data, correction actions, and motor response curves throughout the entire process, which can be used for subsequent analysis and process optimization. This ensures high-precision and stable delivery and feedback control of flexible ultrathin films during the process, and is especially suitable for roll-to-roll equipment such as linear magnetic tapes and films.

[0047] In summary, the entire multi-stage lateral correction system constitutes a hierarchical and collaborative closed-loop control structure. The laser displacement sensors of the front-stage coarse-adjustment correction unit and the working fine-adjustment correction unit collect real-time data on the belt edge position and transmit the measurement signals to the upper-level control system. The control system records the entire process of lateral sway data, correction actions, and motor response curves. Based on a pre-established lateral dynamic model and the algorithms for the three separate controls, it adjusts process parameters online, performing large-stroke compensation and micron-level dynamic correction on deviation signals at different frequency bands. Control commands are sent to the corresponding drive controllers via communication interfaces, adjusting the actual displacement of the front-stage lateral correction mechanism and the high-rigidity linear drive platform in the working area to achieve dynamic alignment of the belt centerline. Simultaneously, the re-inspection unit continuously monitors the final lateral position of the belt before winding using a vision sensor. When the cumulative residual error exceeds a set threshold, the position of the winding core is compensated and adjusted through the laterally adjustable mechanism. All levels of detection and execution processes are carried out in real time, and the control results are continuously fed back to the upper system to form a closed-loop correction. This enables graded suppression and error accumulation control of lateral sway under micro-tension operating conditions, forming a stable, high-precision, multi-layer collaborative closed-loop feedback system.

[0048] The relevant technical solutions are the same as above, and will not be repeated here.

[0049] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for multi-level control of lateral yaw in a roll-to-roll system for ultrathin films, characterized in that, include: A multi-level lateral correction unit is set up on the roll-to-roll system along the running direction of the ultra-thin film belt: a coarse adjustment lateral correction unit is set at the front end of the belt running path including the unwinding end and its preset range, a fine adjustment lateral correction unit is set in the roll-to-roll processing area, and a re-inspection lateral correction unit is set at the front end of the winding before the belt enters the winding mechanism. The system collects lateral sway data in real time at the front end of the path, the roll-to-roll processing area, and the front end of the take-up, including the lateral position, speed, and tension of the belt. It calculates the difference between the lateral position and the target position at each collection point. Based on the change of the difference over time, and combined with the real-time belt tension and speed collected at the corresponding positions, it determines the control parameters of the corresponding correction units at each level, and performs multi-level control of the ultra-thin film lateral sway. Through closed-loop control, the belt sway is finally controlled within the target processing range. The fine-tuning lateral correction unit's structure and control parameters satisfy the following: it corrects the belt's lateral position relative to the target position by a preset small stroke amplitude oscillation component; the coarse-tuning lateral correction unit's structure and control parameters satisfy the following: it corrects the belt's lateral position relative to the target position by a preset large stroke amplitude oscillation component; the re-inspection lateral correction unit's structure and control parameters satisfy the following: it compensates for and corrects the belt's residual lateral sway relative to the target position before winding; the lower limit of the small stroke amplitude is less than the target processing range, and the upper limit of the small stroke amplitude is greater than the lower limit of the large stroke amplitude.

2. The multi-level control method for lateral yaw of an ultrathin film in a roll-to-roll system as described in claim 1, characterized in that, The correction accuracy of each level of lateral correction unit is quantitatively characterized by the steady-state deviation or peak error of the lateral position of the belt relative to the target position.

3. The multi-level control method for lateral yaw of an ultrathin film in a roll-to-roll system as described in claim 1, characterized in that, Under the condition that the ultrathin film operates within the preset micro-tension control range, the control parameters of each level of the transverse correction unit also satisfy the following: the sum of the external disturbance force and the transverse correction force applied to the belt corresponding to the control parameters is less than the product of the preset tension per unit width of the thin film material and the proportional coefficient corresponding to the preset correction unit structural parameters, wherein the proportional coefficients corresponding to different levels of transverse correction units are different.

4. The multi-level control method for lateral yaw of an ultrathin film in a roll-to-roll system as described in claim 1, characterized in that, The coarse adjustment lateral correction unit is configured to include a first laser displacement sensor and at least one actuator with lateral adjustment capability. The actuator is a servo screw slide or a pneumatic proportional actuator structure. By driving the lateral movement of the platform assembly used to support the roll-to-roll structure, the deviation of the lateral position of the tape at the acquisition position relative to the target position is coarsely adjusted.

5. The multi-level control method for lateral yaw of an ultrathin film in a roll-to-roll system as described in claim 4, characterized in that, The fine-tuning lateral correction unit is configured to include a second laser displacement sensor and an actuator with lateral adjustment capability that works in conjunction with it. The second laser displacement sensor has a higher accuracy than the first laser displacement sensor. The actuator that works in conjunction with the second laser displacement sensor is a servo linear motor or a piezoelectric actuator. By driving the processing station, the target position is changed, thereby achieving fine-tuning of the deviation between the lateral position of the belt at the acquisition position and the target position.

6. The multi-level control method for lateral yaw of an ultrathin film in a roll-to-roll system as described in claim 1, characterized in that, The fine-tuning lateral correction unit has the same correction accuracy as the coarse-tuning lateral correction unit. k times, k >1; k The value range satisfies the following: the coarse adjustment lateral correction unit compresses the lateral sway amplitude of the belt to within the working range of the preset stabilization processing of the fine adjustment lateral correction unit, and the tolerance of the coarse adjustment lateral correction unit to disturbances in the belt's running tension during execution is higher than the corresponding disturbance tolerance of the fine adjustment lateral correction unit; and k The specific value is determined comprehensively based on the stability requirements of the belt offset position in different regions, processing tolerance, and cost control.

7. The multi-level control method for lateral yaw of an ultrathin film in a roll-to-roll system as described in claim 1, characterized in that, The determination of control parameters for the re-inspection lateral correction unit is achieved as follows: The deviation of the belt's lateral position relative to the target position at the sampling location in the re-inspection lateral correction unit based on real-time data acquisition. Calculate the amount of tape wound on the take-up shaft. n The cumulative deviation of the layer is expressed as: When the cumulative deviation exceeds the preset threshold, the control parameters of the re-inspection lateral correction unit are determined based on the cumulative deviation and the belt tension and belt speed collected in real time in the re-inspection lateral correction unit.

8. The multi-level control method for lateral yaw of an ultrathin film in a roll-to-roll system as described in claim 1, characterized in that, The lateral sway data is collected at locations with relatively small tension fluctuations, such as the front end of the path, the roll-to-roll processing area, and the front end of the winding.

9. A multi-level control device for lateral yaw of an ultrathin film in a roll-to-roll system, characterized in that, A method for performing a multi-level control method for lateral sway of an ultrathin film in a roll-to-roll system as described in any one of claims 1 to 8, comprising: a coarse adjustment lateral correction unit disposed on the front end of the path including the unwinding end and the path within a preset range in the running path of the tape; a fine adjustment lateral correction unit disposed on the roll-to-roll processing area in the running path of the tape; a re-inspection lateral correction unit disposed on the front end of the winding mechanism before the tape enters the winding mechanism; and a control module. The control module is used to collect lateral sway data in real time at the front end of the path, the roll-to-roll processing area, and the front end of the winding through the lateral correction units at each level; and to coordinately adjust the control parameters of the lateral correction units at each level in conjunction with the real-time collected belt tension.

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