Tenter setting machine intelligent control system based on cloth state online sensing

Abstract

The application discloses a tenter intelligent control system based on cloth state online sensing, and relates to the technical field of textile control, and comprises the following contents: first, high-temperature environment medium in a processing chamber is extracted, in-situ catalytic reforming is performed on the high-temperature environment medium to form isogenic isothermal clean fluid, and a light-transmitting window is used for heating to realize hot-state safety domain locking; then, the fluid is introduced into a pneumatic steady flow bottom plate to form wall-attached negative pressure and central stagnation air cushion, so that cloth surface is kept in a focusing target area; subsequently, high-definition microscopic images are collected, two-dimensional affine deformation tensors are extracted, and a final shrinkage rate prediction evolution track is generated; finally, the track is used for linkage control of overfeed rollers and circulating air fans in each independent temperature zone, and the sensing detection module is driven to retreat under abnormal working conditions, so that stable imaging in the chamber, prepositioned prediction setting state, reduction of control lag and improvement of operation safety are realized, meanwhile, window fogging and coking and cloth surface contact disturbance are avoided, and setting stability is enhanced.

Description

Technical Field

[0001] This invention relates to the field of textile control technology, specifically to an intelligent control system for a tenter frame based on online sensing of fabric condition. Background Technology

[0002] Heat setting machines for fabrics are widely used in the conveying process of finishing woven fabrics, knitted fabrics, and fabrics containing elastic fibers. They achieve dimensional stability through chain clamp conveying, overfeed adjustment, hot air circulation, and temperature zone control. On existing production lines, process engineers typically set overfeed, machine speed, and temperature zone parameters based on fabric structure, weight, and target width. The fabric operates continuously, passing through feeding, stretching, heating, and unloading stations. The stability of the process is related to the matching requirements of front-end inspection, process transmission, and subsequent control.

[0003] Chinese patent document CN113392808A discloses an overfeed control scheme for fabrics on a setting machine. In this document, a reading mechanism and a fabric detection mechanism are installed on the fabric feeding side, fabric output side, or at the overfeed mechanism itself. The reading mechanism acquires fabric classification information, and the fabric detection mechanism acquires fabric images or fabric texture information. The setting machine's electrical controller or a separately set electrical controller calls a processing template to acquire the image or fabric texture information and calculates the overfeed amount based on the measured fabric density, assigning it to the overfeed mechanism to complete the overfeed control during the setting process. Similarly, Chinese patent document CN210085890U discloses a scheme that sets up a weft density detection mechanism based on machine vision in a weft straightening or weft straightening and weft straightening machine, connected to the setting machine's electrical controller, and adjusts the overfeed roller based on the detection results. The commonality between these schemes is that the main detection objects are fabric images, textures, or weft density information, and the control output is mainly focused on overfeed adjustment, belonging to a technical route where overfeed execution is driven by local detection results.

[0004] The above solutions can meet the overfeeding requirements when using images, textures, or weft density as control criteria, but they still have the following drawbacks in stretching and setting applications with large spans, multiple temperature zones, and strong hot air circulation. Summary of the Invention

[0005] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides an intelligent control system for a tenter frame based on online sensing of fabric surface condition. Fluid is introduced into a pneumatically stabilized base plate, creating a negative pressure against the wall and a central stagnation point air cushion to keep the fabric surface in the focusing target area. Subsequently, high-resolution microscopic images are acquired, a two-dimensional affine deformation tensor is extracted, and a final shrinkage rate prediction trajectory is generated. Finally, the overfeed rollers and independent temperature zone circulating fans are controlled in conjunction with the trajectory, and the sensing and detection modules are driven to retract under abnormal operating conditions. This achieves stable intracavity imaging, pre-prediction of the shaping state, and avoids fogging and focusing of the viewing window and fabric surface contact disturbance, thus enhancing shaping stability and solving the technical problems described in the background art.

[0006] (II) Technical Solution To achieve the above objectives, the present invention provides the following technical solution: The intelligent control system for the tenter frame based on online sensing of fabric condition includes a sensing and detection module set in the processing chamber and a control center connected to it. The sensing and detection module is used to extract the high-temperature environmental medium in the processing chamber, which is then catalytically reformed in situ to form a homogeneous isothermal clean fluid sprayed along the outside of the light-transmitting window. The light-transmitting window is heated to keep the surface temperature of the window between the phase change dew point and the polymerization critical temperature. The sensing and detection module is also used to introduce the same source isothermal clean fluid into the pneumatic flow stabilizing base plate to form a negative pressure attached to the wall when the fabric surface is far away and a central stagnation point air cushion when the fabric surface is close to it. The camera assembly collects microscopic images of the focusing target area. The control center is used to extract the two-dimensional affine deformation tensor from the microscopic image, generate the final shrinkage rate prediction evolution trajectory, and control the overfeed roller and the circulating fans of each independent temperature zone in conjunction with the final shrinkage rate prediction evolution trajectory.

[0007] Furthermore, before the high-temperature environmental medium enters the in-situ catalytic reforming, the sensing and detection module passes through the demisting section and the swirling settling section in sequence; the control center determines the phase change dew point based on the bypass humidity, total pressure and partial pressure of volatile components, and determines the polymerization critical temperature based on the finishing agent formulation.

[0008] Furthermore, the pneumatic flow stabilizing base plate includes an outer edge guide ring, a circumferential exhaust groove, a central microporous area, and a pressure-reducing chamber located below the central microporous area; the homogeneous isothermal clean fluid flows along the outer edge guide ring and the circumferential exhaust groove, and when the fabric surface approaches the critical spacing, the stagnation air cushion is output from the central microporous area.

[0009] Furthermore, the control center first performs inter-frame drift correction on the microscopic image, then constructs a reference lattice and the current lattice based on the intersection nodes of the warp and weft yarns, extracts the two-dimensional affine deformation tensor, and generates and caches the final shrinkage rate prediction evolution trajectory according to multiple spatial segments of the remaining transmission path.

[0010] Furthermore, when the control center detects a sharp drop in the catalytic bed air pressure corresponding to in-situ catalytic reforming, it sequentially performs actions such as cutting off the bypass blocking air curtain, stopping the heating of the light-transmitting window, and generating an optical failure alarm within the current control cycle, and writes the optical failure alarm into the current operating status.

[0011] Furthermore, when the camera assembly forms a focusing target area on the pneumatically stabilized base plate, it continuously acquires high-definition microscopic images of the focusing target area. The high-definition microscopic images at least cover the area where the warp and weft yarns intersect, and are sent to the control center according to the acquisition sequence of adjacent frames and maintain the timing correspondence.

[0012] Furthermore, when the control center detects that the main transmission line speed has dropped below the safety threshold and the local heat flux dissipation is interrupted, it triggers the passive phase change component linked with the aerodynamic flow stabilizing base plate to perform gravity escape unloading, and records the triggering state of the passive phase change component and the retreating state of the sensing and detection module in chronological order.

[0013] Furthermore, the in-situ catalytic reforming unit includes a Pt-Pd composite ceramic microchannel configured in the bypass air duct. The Pt-Pd composite ceramic microchannel is connected to the bypass air duct. Homogeneous isothermal clean fluid is sprayed through a Laval micro-slit nozzle along the outside of the light-transmitting window. The transparent heater is an ITO conductive film disposed in the light-transmitting window.

[0014] Furthermore, the pneumatic flow stabilizing base plate includes an outer edge guide ring, a circumferential exhaust groove, a central microporous area, and a pressure-reducing chamber located below the central microporous area. The homogeneous isothermal clean fluid flows along the outer edge guide ring and the circumferential exhaust groove, and forms a stagnation air cushion in the central microporous area when it approaches the fabric surface.

[0015] Furthermore, the sensing and detection module also includes a support slide rail, a support locking pin located at the observation position, and a shape memory alloy spring. The support slide rail limits the backward movement direction of the sensing and detection module. In the event of a power outage or fabric breakage, the shape memory alloy spring releases the support locking pin, causing the sensing and detection module to fall backward along the support slide rail under gravity.

[0016] (III) Beneficial Effects This invention provides an intelligent control system for a tenter frame based on online sensing of fabric condition, which has the following advantages: The high-temperature environment medium in the processing chamber is introduced into an in-situ catalytic reforming process to form a homogeneous isothermal clean fluid. Heating the light-transmitting window creates a thermal safety zone, locking the sensing module and enabling it to maintain a stable optical path within the high-temperature, volatile processing chamber. The homogeneous isothermal clean fluid is introduced into a pneumatically stabilized base plate, creating a negative pressure on the wall when the fabric is far away and a central stagnation point air cushion when it is close, keeping the fabric near the focusing target area in a non-contact manner to prevent mechanical contact from affecting image quality. High-resolution microscopic images are continuously acquired within the focusing target area, and a two-dimensional affine deformation tensor is obtained from the control center. This allows changes in the fabric's micro-mesh to be identified before macroscopic dimensional changes, moving the shaping control inlet to the front-end state quantity.

[0017] By using a two-dimensional affine deformation tensor to form the final shrinkage rate prediction trajectory along the remaining transmission path, the control center can obtain the trend of changes along the path before the fabric reaches the exit end, thereby reducing the lag of tail feedback control under long path and large time delay conditions.

[0018] The overfeed roller and independent circulating fans in each temperature zone are controlled in conjunction with the predicted evolution trajectory of the final shrinkage rate. Tension regulation and heat setting regulation are simultaneously applied to the same control chain to prevent cascade coupling fluctuations caused by repeated compensation of a single execution quantity. The above-mentioned intracavity imaging, non-contact focus retention, pre-prediction, and linkage regulation are formed into a continuous closed loop. Under abnormal operating conditions, the passive phase change component drives the sensor detection module to retreat, so that the scheme takes into account both continuous stability and boundary safety. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall closed-loop architecture of the present invention for predicting and controlling the fabric shrinkage rate of a tenter frame. Figure 2 This is a cross-sectional schematic diagram of the sensing and detection module structure of the present invention, which includes a bypass air duct, an in-situ catalytic reforming unit, a Laval micro-slit nozzle, a light-transmitting window, and a camera assembly. Figure 3 This is a schematic diagram of the dual-boundary thermal survival corridor locking and failure avoidance control of the light-transmitting window of the present invention; Figure 4 This is a cross-sectional schematic diagram of the pneumatic flow stabilizing base plate and non-contact coke preservation structure of the present invention, which includes an outer edge guide ring, a circumferential exhaust groove, a central microporous area and a pressure relief cavity. Figure 5 This is a schematic diagram of the near-distribution flow field topology reversal, stagnation point air cushion lifting and normal resultant force limiting mechanism of the present invention; Figure 6 This is a schematic diagram of the process for de-macro-drifting and solving the two-dimensional affine deformation tensor of continuous microscopic image sequences according to the present invention. Figure 7 This is a schematic diagram of the spatiotemporal digital twin prediction and rolling decoupling control closed loop based on two-dimensional affine deformation tensor of the present invention; Figure 8 This is a schematic diagram of the passive unloading and chain detachment process and the retraction process of the sensing and detection module of 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] Please see Figures 1-8 This invention provides an intelligent control system for a tenter frame based on online sensing of fabric surface condition, comprising: Step 1, without introducing external cold air to disrupt the thermal balance of the drying chamber, converting the high-temperature volatile medium in the processing chamber that would normally blind the sensing and detection modules into a homogeneous isothermal clean fluid that can be used to protect the light-transmitting window and stabilize the optical path, and thereby locking the surface temperature of the light-transmitting window in a hot survival corridor that is neither liquefied and fogged nor thermally decomposed and coked.

[0022] The following actions are executed collaboratively by the sensing and detection module and the control center. The bypass ventilation, in-situ catalytic reforming, and isothermal advection air curtain injection are handled by the sensing and detection module, while the exhaust process parameter input, phase change determination, transparent heater adjustment, and failure avoidance are handled by the control center. This action allocation is because the destructive factors in the processing chamber are not simply excessively high temperatures, but rather a combination of high temperatures, silicone oil volatiles, finishing agent droplets, and strong lateral convection formed by the main circulation fan. If the cold air isolation scheme is still used, although it can temporarily disperse the droplets, the cold source will drag the surface of the transparent window below the dew point, subsequently forming an adhesive liquid film. This liquid film is then baked again in the high-temperature zone, turning into a coking deposit, ultimately leading to complete optical path de-transparency.

[0023] Therefore, this step does not regard the environmental medium as an external enemy that needs to be isolated. Instead, it first swallows the environmental medium into the bypass ventilation channel and then completes on-site reorganization under high temperature conditions, so that the original heat of the environment is transformed from a destructive factor into a self-cleaning driving force.

[0024] A bypass air intake channel is provided on the housing of the sensing module. The inlet of the bypass air intake channel is arranged in the direction of the main circulating airflow in the processing chamber, so that the environmental medium entering the bypass air intake channel is sampled by a grazing suction method, rather than being directly entrained by large pieces of fiber debris by a frontal suction method. An in-situ catalytic reforming unit is connected in series behind the bypass air intake channel. The in-situ catalytic reforming unit adopts a honeycomb ceramic substrate and a noble metal catalytic layer attached to the wall of the microchannel. The noble metal catalytic layer is preferably a platinum-palladium composite layer, but it can also be replaced by a platinum-rhodium composite layer with equivalent flameless oxidation capability. The hydraulic characteristic size of the microchannel is smaller than that of the bypass air intake channel to lengthen the residence path of the high-temperature volatile medium against the wall, so that the volatile organic components can be cracked and oxidized without the introduction of an open flame.

[0025] Instead of installing an external preheater, this unit directly utilizes the existing heat from the processing chamber as the activation temperature, ensuring that the gas leaving the in-situ catalytic reforming unit maintains the same temperature as the processing chamber environment. Specifically: Among them, the degree of reorganization : The degree of self-cleaning completion of the in-situ catalytic reforming unit for high-temperature volatile media, taken as a dimensionless quantity greater than 0. The larger the value, the higher the cleanliness level that can be used to form an isothermal advection gas curtain; residence time : The effective residence time of the environmental medium in the microchannel, which is a positive value and is constrained by both the bypass ventilation channel flow rate and the microchannel length; Among them, the effective dwell time of bypass Indicates the effective residence time of the environmental medium in the in-situ catalytic reforming unit, used to measure whether the catalytic reaction has sufficient contact time; effective flow volume. The structural parameters of the in-situ catalytic reforming unit are determined after assembly by the microchannel length, channel cross-section, and number of parallel channels, and stored in the control center; bypass volumetric flow rate. The flow rate is collected online by the flow meter in the bypass air duct. Among them, ash load Used to characterize the degree of contamination or blockage of the catalyst layer; current pressure difference. The pressure difference is collected online by differential pressure sensors installed before and after the catalytic unit; clean baseline pressure difference. These are reference values ​​recorded after a new catalyst layer is applied or after cleaning and maintenance, used for initialization. Among the remaining parameters, ambient temperature... Temperature data collected by the bypass inlet temperature sensor; volatile component concentration. Acquired by a photoionization detector or flame ionization detector at the bypass inlet; pre-exponential factor With activation energy The parameters are given by the catalyst layer at the factory and stored in the control center using the catalyst layer model as an index; gas constant. The threshold is a known constant and requires no additional data acquisition; The formula is determined by combining the variety formula table and the catalyst layer model.

[0026] Pre-exponential factors : Apparent reaction frequency constant of the catalyst layer under baseline conditions, taking a positive value, determined by the catalytic material system; activation energy : The reaction energy barrier of high-temperature volatile components on the catalyst layer surface, taken as a positive value; gas constant. is a thermodynamic constant, taking positive values; ambient temperature : Absolute temperature of the medium being extracted from the processing chamber, a positive value that varies with the temperature field of the process section; Concentration of volatile components. : Content of degradable volatile organic components in the extracted medium, with a non-negative value; Ash load The degree to which dust or residue on the surface of the catalyst layer inhibits flow and reaction; the value is non-negative. The control center reads the adequacy of the reorganization. After estimating the results, if they fall within the allowable range, the same source of isothermal clean fluid is driven into the Laval micro-slit nozzle. The Laval micro-slit nozzle is arranged circumferentially or in a slit pattern along the outer edge of the transparent window, causing the ejected isothermal clean fluid to sweep across the outer surface of the window in a wall-hugging manner, forming an isothermal advection air curtain. The function of the isothermal advection air curtain is not simply to disperse impurities, but to establish a thin advection interface with a temperature close to that of the main body of the treatment chamber, but with a cleaner composition and a more controlled flow direction. This prevents droplets from directly contacting the transparent window, while also avoiding new thermal stress caused by the intrusion of external cold air.

[0027] Preferably, the bypass air intake channel passes through a demisting section and a swirl settling section before entering the in-situ catalytic reforming unit to first intercept fiber fly shavings and large-diameter droplets, and then delivers the predominantly gaseous environmental medium into the Pt-Pd composite ceramic microchannel. The oxygen source for the in-situ catalytic reforming unit is taken from the residual oxygen in the circulating air of the processing chamber; when the residual oxygen is insufficient, a limited flow of air is introduced through the supplementary air branch to supplement the oxygen required for the reaction. The outlet of the in-situ catalytic reforming unit is connected to the remixing branch to form a mixing chamber. The control center adjusts the remixing ratio according to the temperature difference between the outlet and the ambient temperature, so that the fluid leaving the mixing chamber is of the same origin in temperature as the processing chamber, and the proportion of high-boiling-point condensable components and easily polymerizable components is reduced, thereby forming the homogeneous isothermal clean fluid.

[0028] When the online unit is powered on, the operator can observe the following continuous actions: the hot mist from the drying chamber is first drawn into the module's side cavity by the bypass air duct; after a few breaths, the white mist no longer hangs on the outer surface of the transparent viewing window, and the warp and weft intersection of the fabric surface aligned with the camera assembly becomes clear again, maintaining this clarity regardless of vehicle speed. As a parallel expansion solution, the isothermal advection air curtain can be formed by single-sided slit spraying or by double-sided spraying; the transparent front cover can be made of quartz glass, sapphire glass, or transparent ceramic with equivalent light transmittance and heat resistance, as long as a horizontal isolation layer is established along its outer side by a homogeneous isothermal clean fluid.

[0029] The control center pre-stores the reforming allowable threshold corresponding to the catalyst layer model, and measures the sufficiency of reforming by bypass flow rate, pressure difference before and after the catalyst unit, VOC concentration at the bypass inlet, and bypass inlet temperature. Estimates are made. The bypass flow rate is collected by a flow meter installed in the bypass duct, the pressure difference before and after the catalytic unit is collected by a differential pressure sensor, the VOC concentration is collected by a VOC detector at the bypass inlet, and the bypass inlet temperature is collected by a temperature sensor. The control center only performs adjustments based on the reforming adequacy. The transparent window air curtain branch is opened when the reorganization level is not lower than the reorganization allowable threshold; when the reorganization is sufficient... When the value is below the remodeling allowable threshold, the transparent window air curtain branch is closed and the optical failure mark is set.

[0030] After the isothermal advection gas curtain has been established, the focus shifts to temperature boundary tuning on the surface of the transparent window. The control center does not employ single-threshold heating; instead, it simultaneously receives exhaust gas humid heat information, finishing agent composition information, and the outlet status of the in-situ catalytic reforming unit. It calculates the condensation and coking risks on the transparent window surface and defines the gap between these risks as the hot survival corridor. The transparent heater is preferably an indium tin oxide conductive film deposited on the inner surface of the transparent window, but it can also be replaced with a fluorine-doped tin oxide conductive film or a transparent metal mesh. Its energized area is coaxially arranged with the observation area, ensuring that the heating path coincides with the imaging path, thus avoiding localized instability where the edges are hot while the center is cold.

[0031] To ensure that the thermal survival corridor always operates within the boundary conditions of a homogeneous, isothermal, clean fluid, the control center calculates the safety margin using the following formula: Among them, hot margin The minimum safe distance between the surface of the light-transmitting window and the condensation and coking boundaries; the value can be positive, zero, or negative. A positive value indicates that the surface of the light-transmitting window is within the thermal survival corridor; window temperature. The current temperature of the transparent window surface, a positive value, is determined by the heat exchange between the transparent heater and the environment; dew point temperature. The critical temperature at which the aerosol in the current processing chamber undergoes a phase change and fogging is taken as a positive value and is calculated by combining the exhaust process parameters and component information. Coking critical temperature : The critical temperature at which residual volatile components undergo dehydrogenation polymerization and form coke deposits, taken as a positive value; Dew point isolation To avoid liquefaction and fogging at the dew point temperature The safety temperature difference reserved above is preferably the temperature difference boundary given by the aforementioned process; coking isolation amount To avoid thermal cracking and coking at the critical coking temperature The safety temperature difference reserved below is preferably the temperature difference boundary given by the aforementioned process; When the hot margin When the value is greater than 0, the control center maintains the transparent heater in slow-motion operation; when the thermal margin is... As the pressure approaches zero, the control center prioritizes fine-tuning the power of the transparent heater and rechecks the bypass induced draft channel flow rate and the pressure drop of the in-situ catalytic reforming unit; when the hot margin... When the pressure drop is less than 0 and an abnormal pressure drop in the catalytic bed occurs simultaneously, the control center determines that the problem is no longer simply temperature drift, but rather instability of the source of the isothermal clean fluid. Therefore, it executes a failure avoidance mechanism: closing the Laval micro-slit nozzle, stopping the transparent heater from heating further, and sending an optical failure flag to the subsequent control chain so that step two no longer relies on the output of this window for coke preservation. During the online processing of silicone-containing soft finishing fabric, another set of on-site actions can be observed: after the fabric enters the high-temperature section, the transparent heater on the inner surface of the light-transmitting window first heats up uniformly. Subsequently, the control center maintains the temperature within a narrow range based on changes in the exhaust gas. The surface of the light-transmitting window remains clean and transparent throughout, without any water droplet-like fogging or yellowish-brown hard adhesion spots.

[0032] The surface temperature of the light-transmitting window is obtained by combining the temperature compensation model of the window center with the thin-film platinum resistance thermometer attached to the edge of the light-transmitting window; the real-time phase change dew point is obtained by looking up tables based on bypass humidity, pressure, and partial pressure of volatile components; the coking critical point is retrieved from a pre-built material database based on the type and ratio of finishing agents in the current process formula. The dew point isolation amount and coking isolation amount are stored as product formula parameters in the control center and are switched synchronously when changing fabric or formula.

[0033] Step 2: Using the homogeneous isothermal clean fluid formed in Step 1, a single-chain fluid mechanism is constructed below the sensing and detection module. This mechanism includes far-field wall-attached negative pressure to pull the device closer, near-field blockage and stagnation point lifting, and critical zone combined force flipping and limiting. This allows the dynamic fabric to return to the focusing target area of ​​the camera assembly without contacting the hardware surface.

[0034] This step does not create a new air source; instead, it directly inherits the isothermal clean fluid from step one. The reason for this is that introducing additional room-temperature compressed air, while creating a localized blowing effect, would disrupt the thermal boundary established in step one, leading to condensation edges and refraction fluctuations near the light-transmitting window. Relying solely on mechanical pressure rollers or guide yarns would leave scratches and lateral tears on the fabric surface in the high-temperature zone. Therefore, this step continues to introduce the isothermal clean fluid overflowing from the outside of the light-transmitting window into the pneumatically stabilized flow base plate, allowing the same airflow to simultaneously perform four actions: heat preservation, flow guidance, approach, and lifting. The control center here only handles access judgment and exposure triggering: when the thermal margin... When the condition remains positive and the optical failure marker is not set, the control center allows the camera assembly to enter the short exposure acquisition state; when any condition fails, the camera assembly stops receiving the output image of this step, thereby avoiding sending the out-of-focus texture into step three.

[0035] Preferably, the homogeneous isothermal clean fluid is first divided into a light-transmitting window air curtain branch and a bottom plate guide branch in the flow distribution cavity. The former continuously maintains the isothermal advection air curtain on the outer surface of the light-transmitting window, while the latter enters the pneumatically stabilized bottom plate to form an attached flow.

[0036] The pneumatic flow stabilizing base plate includes an outer guide ring, a circumferential exhaust groove, a central microporous area, and a pressure-reducing chamber located below the central microporous area. When the fabric surface is at the far-field distance, the guide branch of the base plate forms a negative pressure that pulls the fabric surface closer to the wall. When the fabric surface approaches the critical distance, the effective discharge cross-section of the circumferential exhaust groove decreases due to the proximity of the fabric surface, resulting in local exhaust obstruction and a rise in central pressure. The central microporous area outputs a stagnation point air cushion lifting effect, thereby enabling the fabric surface to maintain non-contact passage near the focusing target area.

[0037] First, we will focus on the geometric configuration of the pneumatic flow stabilizing base plate. The pneumatic flow stabilizing base plate is arranged coaxially with the light-transmitting window. Its upper surface is continuously composed of an outer guide ring, a circumferential exhaust groove, and a central microporous area. The outer guide ring adopts an Archimedean surface that gradually rises towards the fabric surface. The outer end of the surface is connected to the overflow channel of the homogeneous isothermal clean fluid, and the inner end of the surface transitions to the circumferential exhaust groove, which then encloses the central microporous area.

[0038] The substrate of the pneumatic flow stabilizing base plate is preferably heat-resistant stainless steel or nickel-based alloy, and its surface is covered with a dense ceramic layer to reduce fiber fly shavings adhesion; an aerogel heat insulation pad or a thermal break with equivalent function is preferably provided between the pneumatic flow stabilizing base plate and the housing of the sensing module to prevent the flow channel temperature field from being lowered by the heat conduction of the housing.

[0039] With this arrangement, the homogeneous isothermal clean fluid first spreads along the outer edge guide ring, then is drawn into a high-speed, thin-layer flow in the circumferential direction through the circumferential exhaust channels. As long as the fabric surface is within a relatively large overhang distance, it will be drawn towards the coagulating target area by the low-pressure pull caused by the wall flow. Specifically: Among them, negative pressure strength : The intensity of the attraction effect formed by the far-field wall flow between the fabric surface and the aerodynamically stable base plate, with non-negative values; fluid density. The density of the homogeneous isothermal clean fluid is a positive value, and its value is constrained by the temperature boundary formed in step one. Attached flow rate : The volumetric flow rate that enters the outer guide ring and expands circumferentially, taking a positive value; guide radius : The equivalent annular radius of the outer guide ring, which is a positive value; the suspension space distance. : The normal distance between the fabric and the upper surface of the pneumatic flow stabilizer base plate, which is a positive value; Furthermore, in the wall flow With the upstream already largely constrained, the suspended space distance The larger the negative pressure intensity Reduced in a continuous manner; suspended space distance When shrinking, negative pressure intensity The intensity gradually increases, but it has not yet entered the collision zone. When the fabric is threaded through the line, the operator can see the fabric end first swaying up and down under the blowing of the main air box. Then, as it passes under the sensor detection module, the fabric surface does not touch the bottom plate, but is slowly pulled back to the vicinity of the observation axis as if by an invisible hand. The yarn pattern seen by the camera assembly changes from a blurry jump to a discernible outline.

[0040] As a parallel extension, the outer edge guide ring can also adopt a multi-segment broken line approximation surface, as long as it can still enable the homogeneous isothermal clean fluid to form a continuous wall-attached spread and establish a closing effect at the circumferential exhaust groove. Furthermore: the homogeneous isothermal clean fluid that has been stabilized in step one can directly form a far-field closing effect, reducing the need for additional air sources, and pressing the initial large swing of the fabric surface into the area that can be controlled by the subsequent support structure.

[0041] Preferably, the bypass airflow channel does not use an independent external long pipe, but instead utilizes the original cavity inside the amplitude adjustment screw mounting base or adjacent maintenance pipelines to form a first-section bypass microchannel, thereby shortening the high-temperature medium transport path and reducing heat loss. An aerogel heat insulation sleeve or aerogel heat insulation ring is installed between the first-section bypass microchannel and the lens mounting base, allowing the bypass microchannel to maintain the temperature level of the high-temperature medium, while the lens mounting base, transparent heater lead end, and image acquisition unit mounting position do not directly bear the heat conducted by the frame.

[0042] As the fabric continues to be pulled closer by the far-field wall-attached negative pressure, it enters the critical spacing control stage. If a single negative pressure is maintained at this point, the fabric will directly adhere to the surface of the pneumatic flow stabilizing base plate, which will not only block the light path but also cause abrasions in the high-temperature section.

[0043] This step therefore involves creating a pressure-reducing chamber below the central microporous area and maintaining a narrow neck transition zone between the circumferential exhaust groove and the central microporous area. When the suspension space distance... Greater than the critical spacing At this time, the wall-attached flow discharged from the circumferential exhaust groove can still be smoothly released, and the central microporous area is only in a low-speed air replenishment state; when the fabric surface approaches the critical spacing At this point, the flow cross-section of the circumferential exhaust channel is geometrically blocked by the fabric surface, and the release path of the attached flow is suddenly restricted. The gas in the depressurization chamber is instead pushed out through the central microporous area, forming a stagnant air cushion in the center of the base plate. As a result, the previously continuously increasing attraction effect is interrupted by a normal lifting effect. The fabric surface no longer continues to impact downwards, but instead moves back and forth slightly within a narrow range and maintains an imageable posture.

[0044] To make this flipping process feasible, the central micropore region preferably uses a concentric ring array or a quincunx micropore array; the orifice direction of the micropores is consistent with the normal direction of the base plate to avoid the yarn texture being blown off-center by oblique spraying; the pressure relief chamber can be formed by milling a single piece of metal or by sintering a stacked diffuser plate, as long as the upstream is still connected to a homogeneous isothermal clean fluid. Among these: Among them, stagnation pressure : Normal lifting pressure formed in the central microporous region, with a non-negative value; fluid density The density of the isothermal clean fluid originating from the same source is taken as a positive value and has the same meaning as in the previous formula; the wall-attached flow rate. : The volumetric flow rate that enters the pneumatically stabilized bottom plate and participates in pressure transfer; this value is positive and has the same meaning as in the previous formula; equivalent area of ​​micropores. : The total equivalent area of ​​all flow orifices in the central microporous region, with a positive value; Congestion trigger coefficient The pressure transfer ratio after the circumferential exhaust channel transitions from smooth venting to geometric sealing, with a value ranging from 0 to 1; when the suspension space distance... Greater than the critical spacing At that time, congestion triggering coefficient Take zero; when the dangling space distance Descend and enter the critical gap The following is the congestion trigger coefficient. It increases monotonically according to a preset interpolation rule; Among them, the congestion triggering coefficient Characterizes the degree to which the central microporous area transitions from unsupported to fully supported; suspension space distance Indicates the normal distance between the fabric surface and the aerodynamic flow stabilizer plate; critical distance. This indicates the inflection point where significant airflow obstruction begins to appear in the circumferential exhaust channels; minimum safe clearance. This indicates the minimum non-contact distance allowed in the design calibration. Online measurements are not required; they can be obtained offline through feeler gauges or laser ranging, and the base plate design curve can be generated.

[0045] Critical Spacing The spacing boundary where significant geometric sealing begins to appear in the circumferential exhaust grooves is taken as a positive value, which is determined by the geometry of the base plate and the thickness of the fabric. Among them, the resultant force of normal direction : The net vertical force acting on the fabric surface, which can be positive, zero, or negative; a negative value indicates that the pulling force is dominant, while a positive value indicates that the lifting force is dominant; the area of ​​micropore action. Stagnant pressure The effective area of ​​the fabric surface subjected to lifting action is taken as a positive value; stagnation pressure The lifting pressure formed by the central microporous region and the pressure-relieving cavity is a non-negative value and has the same meaning as the previous formula; the negative pressure area. Negative pressure intensity The effective area for applying a pulling force to the fabric surface is taken as a positive value; negative compressive strength The convergence pressure formed by the outer guide ring and the circumferential exhaust groove is a non-negative value and has the same meaning as the previous formula. When the resultant normal force When reversing near zero, the fabric surface is confined within the focusing target area and does not cross the base plate surface. A representative implementation is as follows: a sensing module is installed near the observation window of the first oven section. As the fabric passes through, it is first pulled closer by the outer guide ring, and then an invisible lifting layer is formed above the central microporous area. The fabric surface remains smooth above this lifting layer, and the camera assembly continuously sees the warp and weft yarn intersections without any blurry stripes caused by plate bounce. To accommodate the switching between thick and thin fabrics, the critical spacing... This can be achieved by replacing the circumferential limiting rings with different thicknesses, or by changing the total area of ​​the orifice in the central micro-hole region; the trigger signal of the camera assembly is synchronized with the speed encoder, so that what is received in step three is not an isolated image, but a continuous sequence of microscopic images with a temporal order.

[0046] Furthermore, by utilizing the approach motion of the fabric itself to trigger the topological flip of the flow field, the originally dangerous moment before collision is transformed into a focusing limit switch, and no additional high-speed valves or close-to-fabric contact components are required throughout the process.

[0047] Step 3: Proceed the continuous microscopic image sequence acquired by the camera assembly from being clearly visible to being solvable, and convert the pre-stress release morphology of the fabric micro-mesh into the shrinkage rate prediction evolution trajectory that can be directly used by the control center.

[0048] The following actions are completed collaboratively by the camera assembly, the underlying coprocessor, and the control center. The camera assembly is responsible for acquiring a continuous sequence of microscopic images in the focusing target area. The underlying coprocessor is responsible for image preprocessing, lattice cell locking, and two-dimensional affine deformation tensor calculation. The control center is responsible for sending the two-dimensional affine deformation tensor and the process status into the spatiotemporal digital twin proxy model.

[0049] To ensure the spatiotemporal digital twin proxy model has a clear implementation path, the control center discretizes the remaining path from the current observation position to the fabric output end into multiple spatial segments, and sets a cumulative shrinkage state for each spatial segment. The control center takes the two-dimensional affine deformation tensor of the current frame, the current ambient temperature, the current linear velocity, and the current tension state as joint inputs, and recursively calculates the cumulative shrinkage state at the end of each spatial segment in sequence to obtain the predicted trajectory vector. The recursive coefficients of each spatial segment are not learned online, but are obtained offline by calibration according to fabric type, finishing formula, and linear velocity level, and stored in the control center with the formula number as an index.

[0050] The reference lattice basis matrix is ​​obtained by averaging stable grids in consecutive clear frames after power-on; the current lattice basis matrix is ​​obtained by sub-pixel cross nodes; the matrix logarithm is achieved through eigenvalue decomposition, and a lower limit is set for excessively small eigenvalues.

[0051] Since step one has already ensured that the light-transmitting window is free of fog, and step two has already ensured that the fabric surface revolves around the focusing target area, this step no longer pursues the macroscopic outline of the entire fabric surface, but instead focuses on the local grid formed by the intersection of warp and weft yarns. The reason for this approach is that the absolute width visible only at the tail of the machine is a consequence, while the changes in yarn intersection angles, grid skewing, and local density rearrangement that first appear at the front of the oven are the precursor signals.

[0052] Control center in hot state margin Maintain positive value, optical failure marker not set, and normal resultant force Under the condition of circling around zero point, a short exposure trigger pulse is sent to the camera assembly, and the fabric speed encoding pulse is simultaneously sent to the low-level coprocessor as a timing reference. The camera assembly preferably adopts a combination of an area array photosensitive chip and a telecentric lens, with a coaxial short pulse illumination device placed in front of the lens to maintain stable brightness at the warp and weft yarn intersections in each frame. The low-level coprocessor first performs bad pixel repair, flat field correction, and local contrast stretching on the continuous microscopic image sequence, and then uses the phase correlation method to calculate the overall translation between adjacent frames, subtracting frame jitter, chain clamp beat disturbance, and small fluctuations in fabric speed from the image in advance.

[0053] Control center in hot state margin Maintain positive, optical failure marker not in place and focus evaluation value When the focus value is not lower than the focus threshold, the camera assembly is allowed to acquire a continuous sequence of microscopic images; when the focus evaluation value When the image value falls below the focus threshold and continues to exceed a predetermined number of frames, the control center pauses inputting the current image frame into the subsequent processing chain in step three. The focus evaluation value... It is obtained by calculating the gradient energy of the image within the focal target area. Among them, the focus evaluation value Indicates the first The sharpness of a frame within the in-focus target area is used to determine whether the frame is allowed to enter the tensor solution chain; number of pixels. Represents the total number of pixels involved in the calculation within the focused target area; lateral gradient With longitudinal gradient Representing pixels The image gradient components at a given location can be computed using the Sobel operator or an equivalent discrete gradient operator; the focus threshold... It is initialized by multiplying the median of the first few clear images after power-on by an empirical coefficient.

[0054] After completing this layer of de-drifting, the bottom coprocessor performs a two-dimensional fast Fourier transform on the local texture window within the focusing target area to extract the warp and weft main frequency bands, and then searches for yarn intersection nodes within the inverse transform window. For each set of stable intersection nodes, the bottom coprocessor does not directly use a single angle as a state variable, but instead constructs a reference lattice basis matrix and the current lattice basis matrix to preserve the coupling relationship when the three deformation components of rotation, stretching, and shear coexist.

[0055] in: Among them, the two-dimensional affine deformation tensor : No. The combined deformation state of the local yarn mesh relative to the reference mesh is as follows: A real matrix, whose diagonal terms describe the stretching and contraction trends in the longitudinal and latitudinal directions, and whose off-diagonal terms describe the shearing trends at the intersections of the mesh; an affine mapping matrix. The mapping from the reference lattice basis matrix to the current lattice basis matrix is ​​invertible. Real matrix; Current lattice basis matrix : No. The frame is a matrix obtained by concatenating two independent lattice basis vectors, with each column corresponding to the meridional basis vector and the lattice basis vector, respectively; the reference lattice basis matrix. The reference grid matrix selected in the stable section at the beginning of the article is invertible. Real matrix; Matrix logarithm operator The logarithmic mapping after eigenvalue decomposition of a positive definite matrix serves to pull the multiplicative transformation relation back into an additive tensor space, facilitating subsequent accumulation along the path; frame number : The temporal position in a continuous sequence of microscopic images, which is a positive integer; A representative implementation is as follows: when the fabric passes through the focusing target area, the camera assembly continuously sees multiple diamond-shaped yarn grids sweeping across the center of the image; the underlying coprocessor first subtracts the common shaking of the entire image, and then calculates the remaining grid skewing and collapsing into a two-dimensional affine deformation tensor. .

[0056] Furthermore: first address macroscopic drift before performing local mesh calculations, thus locking the tensor source to the fabric's own structure rather than frame jitter; use a two-dimensional affine deformation tensor. The coupling relationship between scaling and shearing is preserved, avoiding the simplification of subsequent control inputs into a single, easily distorted width.

[0057] The low-level coprocessor first performs dead pixel repair and flat field correction on the current frame and the previous frame, and then extracts a fixed-size local image window within the focused target area. The low-level coprocessor performs phase correlation calculations on the local image windows of adjacent frames to obtain the translation displacement of the entire window, and uses this to remove the overall drift caused by frame vibration and fabric speed fluctuations. Subsequently, the low-level coprocessor performs a two-dimensional fast Fourier transform on the drift-free local image window to extract the warp and weft main frequency bands, and then locates the yarn crossing nodes in the inverse transform image. The low-level coprocessor uses quadratic surface fitting or gray-level centroid method to correct the subpixel coordinates of each yarn crossing node; when the number of effective crossing nodes is lower than a preset threshold, the current frame is discarded, and the two-dimensional affine deformation tensor is not updated. .

[0058] In the two-dimensional affine deformation tensor After continuous generation, the process transitions to path forwarding. The control center discretizes the remaining oven length of the tenter frame into several spatial segments and configures a local thermodynamic sub-model for each segment. Each local thermodynamic sub-model receives the two-dimensional affine deformation tensor at the same time. Ambient temperature linear velocity and tension state Among them, ambient temperature Temperature data from various temperature zones, linear velocity From the main transmission encoder, tension status It is derived from the tension roller or calculated from the drive current of the overfeed roller.

[0059] The control center does not directly substitute these quantities into a single empirical formula, but instead instructs the spatiotemporal digital twin proxy model to iterate segment by segment along the transmission direction: the local contraction state output from the previous segment enters the next segment, and the next segment is then superimposed with new thermal exposure and tension constraints, until the predicted evolution trajectory of the shrinkage rate is formed along the entire remaining path. Among these: Among them, the predicted trajectory vector From the first The predicted shrinkage rate at the end of each spatial segment after the fabric crosses the remaining path from the frame time is represented as a column vector ordered by the transmission direction; spatiotemporal mapping operator A total mapping consisting of multiple spatial segments connected in series, its function is to progressively transfer and accumulate the local state of the preceding segment to the subsequent segment; a piecewise mapping operator. to Corresponding to the first remaining space segment to the second The local thermodynamic sub-models of the remaining space segments are implemented using finite difference discretization, piecewise cubic Hermite interpolation, or equivalent continuous mapping within each operator. Ambient temperature : No. The frame corresponds to the thermal environment state under the process conditions at that moment, and maintains the same meaning as the ambient temperature symbol in step one; linear velocity. : The running speed of the fabric along the transmission direction, a positive value; tension state : No. The warp stress state of the fabric surface at frame time is positive; the total number of spatial segments : The number of spatial segments discretized from the current observation position to the output end, which is a positive integer; composite operator The series relationship where the output of the previous spatial segment is used as the input of the next spatial segment; A representative implementation is as follows: when the fabric passes the observation position of the first section of the drying oven, the control center has received continuously updated predicted trajectory vectors. Although the operator has not yet observed the width contraction at the tail of the machine, they can already determine from the trajectory at the ends of each spatial segment whether the contraction will continue or stabilize. If the fabric is knitted, the knitted fabric parameter set is used; if it is woven, the woven fabric parameter set is used, and the predicted trajectory vector... The output format remains unchanged.

[0060] Furthermore, on the one hand, the microscopic pre-signal is pushed forward segment by segment along the remaining path to avoid waiting for the tail section to make corrections; on the other hand, the trajectory vector is predicted. At the same time, both the final deviation and the deviation distributed along the process are retained, so that the next step can see both the final deviation and where the deviation begins to accumulate.

[0061] Step 4: Based on the predicted trajectory vector The characteristic deviation distribution along the path is used to generate a decoupled control sequence in advance for the overfeed roller and the circulating fans in each independent temperature zone, while also based on the linear velocity. The abrupt change in the relationship with the near-heat boundary triggers a passive unloading chain.

[0062] This step is executed collaboratively by the control center, the overfeed roller actuator, the independent temperature zone circulating fan actuators, and the unloading mechanism linked to the pneumatic flow stabilizing base plate. Steps one through three have already resolved the issues of light transmission window opacity, fabric defocus, and delayed visibility of the resulting weight. Therefore, this step does not wait for the absolute shrinkage rate measured at the tail of the machine before making corrections; instead, it directly uses the predicted trajectory vector. The information carried along the route.

[0063] If the cascade proportional-integral-derivative (PID) control method is still used, the compensation action of the overfeed roller and the drying action of the temperature zone fan will be intertwined: increased overfeed will cause localized loosening of the fabric, amplifying the effect of the airflow; reduced fan speed will result in insufficient heat setting, leading to further shrinkage in the later stages. Therefore, this step will predict the trajectory vector. Two-dimensional affine deformation tensor Ambient temperature linear velocity and tension state They are fed into the rolling solver chain, changing the control action from chasing after the result to intervening before the result is revealed.

[0064] The control center reads the predicted trajectory vector. Then, it is compared with the process target trajectory vector. The difference is calculated to obtain the deviation vector expanded along the transmission direction. Subsequently, the control center uses the two-dimensional affine deformation tensor... The deviations in the shear and stretching components are determined to be mainly due to meridional constraints or insufficient heat release. Control weights are then allocated to the overfeed rollers and the circulating fans in each independent temperature zone based on their source. The solver preferably uses a sequential quadratic programming solver, an interior-point solver, or a constraint rolling solver with equivalent functionality. When discretizing the prediction model, fourth-order Runge-Kutta integration or implicit trapezoidal discretization is preferred.

[0065] Each time the control center completes a rolling solution, it outputs the first control increment for the current moment, and the remaining control increments are used as the warm-up initial values ​​for the next solution. Wherein: Wherein, cost function : No. The comprehensive evaluation value for the friction deviation, control action amplitude, and micro-deformation risk during the second rolling solution is a non-negative real number; spatial segment number. : The discrete spatial segment number from the current observation position to the output end, with a value of a positive integer; the total number of spatial segments. The number of discrete spatial segments participating in this rolling solution, taking a positive integer value, and maintaining the same sign as the total number of spatial segments in step three; predicted components. Predicted trajectory vector In the Predicted components at the end of each spatial segment; Target component Process target trajectory vector In the Target components at the end of each spatial segment; segment weight matrix : No. The penalty weights for each spatial segment on the deviation are positive semi-definite matrices; the control increment vector... The set of control increments for the overfeed roller and the circulating fans in each independent temperature zone during this solution process; control weight matrix. : Control increment vector The penalty weights are positive definite matrices; the tensor weight matrix is... : For two-dimensional affine deformation tensor The penalty weights are positive semidefinite matrices; the two-dimensional affine deformation tensor : No. The micro-grid deformation state of the frame, and maintain the same meaning as step three; In a preferred embodiment, the control center is installed inside the shaping machine's electrical control cabinet. The overfeed roller driver receives torque input via industrial Ethernet or fieldbus, and the circulating fan drivers for each independent temperature zone receive main frequency input. The control frame includes a timestamp field, actuator number field, target increment field, and acknowledgment verification field. After the fabric passes the first observation position, the control center first reduces the slope of the main frequency change of the fan in the later temperature zones, and then adds a gentler torque increment to the overfeed roller at the fabric inlet end. The operator can then observe that the fabric edge no longer exhibits alternating fluctuations of tightening and rebounding.

[0066] Furthermore, predict the trajectory vector Used in spatial segments, two-dimensional affine deformation tensor Integrating into the cost function, the control center only issues the first control increment, thereby directly converting micro-precursors into execution allocation.

[0067] When the closed-loop process is operating normally, the pneumatic flow stabilizer plate maintains the non-contact distance established in step two between itself and the fabric surface; however, in the event of a complete power outage, fabric breakage, or sudden stop of the main transmission, the linear velocity... It will fall rapidly, and the fabric will no longer carry heat forward. Radiation and stagnant heat near the fabric will accumulate locally. If the sensing module is left in place, the light-transmitting window, the front of the lens, and the edge of the base plate will face the risk of continuous heat damage.

[0068] Therefore, this step establishes a passive unloading chain that does not rely on external power supply or online calculations by the control center. This unloading chain includes a support rail, a locking pin, a shape memory alloy spring, a preload counterweight, and a limiting buffer. Under normal conditions, the locking pin fixes the sensing module in the observation position. The shape memory alloy spring, driven by the nearby high heat, recovers and contracts, pulling open the locking pin. The preload counterweight then moves the sensing module backward along the support rail, and the limiting buffer absorbs the impact at the end.

[0069] The control center continuously monitors the linear velocity during normal power supply periods. and hot margin Once the linear velocity Falling into the stagnation zone and hot residual capacity As the situation continued to deteriorate, the control center issued an early warning, but the passive unloading chain itself was the one that actually completed the disengagement action.

[0070] in: Among them, thermal hysteresis risk : No. The degree of thermal stagnation corresponding to the unit transport capacity of the near-distribution area at any given time, taken as a positive real number; ambient temperature. : Current near-thermal ambient temperature, and maintains the same meaning as the ambient temperature in step three; linear velocity : Current main fabric transmission speed, and maintains the same meaning as the linear velocity symbol in step three; speed buffer amount To avoid linear velocity A positive buffer is introduced when the denominator becomes singular near zero. Its value is a small positive number and is preset by the control center. When thermal stagnation risk Continuously exceeding the warning threshold And it continues for longer than the warning period. At this time, the control center sets a thermal hysteresis warning flag; the thermal hysteresis warning flag is only used for alarm and status recording, and the actual retraction of the sliding carrier is achieved by the mechanical release of the locking pin by the shape memory alloy spring. The warning threshold is... The warning duration is set jointly by the equipment's temperature resistance limit and the product / process limit; Used to prevent false triggering due to short-term disturbances.

[0071] In a representative implementation, after a sudden power outage of the shaping machine, the operator can directly see the sensing module pause briefly in place, followed by the release of the locking pin on the support rail. The entire module then retracts along the support rail away from the fabric surface until it falls into the rear buffer stop. As a parallel extension, the shape memory alloy spring can be replaced with a low-melting-point safety component combined with a mechanical spring, or it can be replaced with a bimetallic strip driven locking pin mechanism, as long as the disengagement action is still directly triggered near the fabric heat boundary and does not rely on external power supply.

[0072] Furthermore, linear velocity With ambient temperature Used together to identify thermal hysteresis risk The passive unloading chain is what actually performs the retraction, and the supporting slide rail, locking pin and limit buffer form a clear mechanical action path.

[0073] As a supplement: the control center explicitly defines the control vector as a joint execution vector composed of the target torque of the overfeed roller and the target main frequency of each independent temperature zone circulating fan, and uses the difference between adjacent control cycles as the control increment vector. The process target trajectory vector is generated by assigning weights to the final shrinkage rate target in the product process sheet and the corresponding standard path. During rolling solution, the control center simultaneously applies constraints on the overfeed roller torque amplitude, torque change rate, main frequency amplitude of each independent temperature zone circulating fan, and main frequency change rate. To directly correlate micro-mesh deformation with actuator allocation, the control center calculates the relative proportions of shear and stretch components in the two-dimensional affine deformation tensor. When the shear component is dominant, the weight of the overfeed roller channel is increased; when the stretch component is dominant, the weight of the subsequent temperature zone circulating fan channel is increased.

[0074] The sensing module, pneumatic flow stabilizing base plate, and camera assembly are all fixed on the same sliding carrier, which moves in a single backward direction along the supporting slide rail. The phase transition temperature range of the shape memory alloy spring is selected between the upper edge of the long-term operating temperature under normal observation conditions and the upper limit of the allowable temperature resistance of the lens front end. The release displacement of the locking pin is greater than the engagement depth of the locking pawl, and an elastic buffer limit block is set at the backward endpoint of the sliding carrier. The control center is designed to mitigate the risk of thermal hysteresis. The calculations are only used for early warning and status recording. The actual action of retraction is the pull-out of the locking pin caused by the contraction displacement generated by the shape memory alloy spring in the phase transition temperature range.

[0075] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein 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 use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0076] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0077] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0078] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0079] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An intelligent control system for a tenter frame based on online sensing of fabric condition, comprising a sensing module installed in the processing chamber and a control center connected thereto, characterized in that: The sensing and detection module is used to extract the high-temperature environmental medium in the processing chamber, which is then catalytically reformed in situ to form a homogeneous isothermal clean fluid that is sprayed along the outside of the light-transmitting window. The light-transmitting window is heated to keep the surface temperature of the window between the phase change dew point and the polymerization critical temperature. The sensing and detection module is also used to introduce the same source isothermal clean fluid into the pneumatic flow stabilizing base plate to form a negative pressure attached to the wall when the fabric surface is far away and a central stagnation point air cushion when the fabric surface is close to it. The camera assembly collects microscopic images of the focusing target area. The control center is used to extract the two-dimensional affine deformation tensor from the microscopic image, generate the final shrinkage rate prediction evolution trajectory, and control the overfeed roller and the circulating fans of each independent temperature zone in conjunction with the final shrinkage rate prediction evolution trajectory.

2. The intelligent control system for the tenter frame as described in claim 1, characterized in that: Before entering the in-situ catalytic reforming process, the sensing and detection module passes through the demisting section and the swirl settling section in sequence. The control center determines the phase change dew point based on the bypass humidity, total pressure and partial pressure of volatile components, and determines the critical polymerization temperature based on the finishing agent formulation.

3. The intelligent control system for the tenter frame as described in claim 2, characterized in that: The pneumatic flow stabilizing base plate includes an outer edge guide ring, a circumferential exhaust groove, a central microporous area, and a pressure-relieving chamber located below the central microporous area; the homogeneous isothermal clean fluid flows along the outer edge guide ring and the circumferential exhaust groove, and when the fabric surface approaches the critical spacing, the stagnation air cushion is output from the central microporous area.

4. The intelligent control system for the tenter frame as described in claim 3, characterized in that: The control center first performs inter-frame drift correction on the microscopic image, then constructs a reference lattice and the current lattice based on the intersection nodes of the warp and weft yarns, extracts the two-dimensional affine deformation tensor, and generates and caches the final shrinkage rate prediction evolution trajectory according to multiple spatial segments of the remaining transmission path.

5. The intelligent control system for the tenter frame as described in claim 1, characterized in that: When the control center detects a sharp drop in the air pressure of the catalytic bed corresponding to in-situ catalytic reforming, it sequentially performs actions such as cutting off the bypass blocking air curtain, stopping the heating of the light-transmitting window, and generating an optical failure alarm within the current control cycle, and writes the optical failure alarm into the current operating status.

6. The intelligent control system for the tenter frame as described in claim 5, characterized in that: When the camera assembly forms a focusing target area on the pneumatically stabilized base plate, it continuously acquires high-definition microscopic images of the focusing target area. The high-definition microscopic images at least cover the area where the warp and weft yarns intersect, and are sent to the control center according to the acquisition sequence of adjacent frames and maintain the timing correspondence.

7. The intelligent control system for the tenter frame as described in claim 1, characterized in that: When the control center detects that the main transmission line speed has dropped below the safety threshold and the local heat flux dissipation is interrupted, it triggers the passive phase change component linked with the aerodynamic flow stabilization base plate to perform gravity escape unloading, and records the triggering state of the passive phase change component and the retreating state of the sensing and detection module in chronological order.

8. The intelligent control system for the tenter frame as described in claim 7, characterized in that: The in-situ catalytic reforming unit includes a Pt-Pd composite ceramic microchannel configured in the bypass air duct. The Pt-Pd composite ceramic microchannel is connected to the bypass air duct. Homogeneous isothermal clean fluid is sprayed through a Laval micro-slit nozzle along the outside of the light-transmitting window. The transparent heater is an ITO conductive film disposed in the light-transmitting window.

9. The intelligent control system for the tenter frame as described in claim 8, characterized in that: The pneumatic flow stabilizing base plate includes an outer guide ring, a circumferential exhaust groove, a central microporous area, and a pressure-reducing chamber located below the central microporous area. The homogeneous isothermal clean fluid flows along the outer guide ring and the circumferential exhaust groove, and forms a stagnation air cushion in the central microporous area when it approaches the fabric surface.

10. The intelligent control system for the tenter frame as described in claim 9, characterized in that: The sensing and detection module also includes a support slide rail, a support locking pin located at the observation position, and a shape memory alloy spring. The support slide rail limits the backward movement direction of the sensing and detection module. In the event of a power outage or fabric breakage, the shape memory alloy spring releases the support locking pin, causing the sensing and detection module to fall backward along the support slide rail under gravity.

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