Resin infusion process control method and control system

Abstract

The application provides a resin infusion process control method and control system, and relates to the technical field of liquid molding. The application introduces a double-zone parallel permeability model to accurately describe the parallel flow characteristics of resin in the gully runner and the fiber preform, breaks the prediction deviation caused by the traditional single model ignoring the regional difference, and realizes fine and active coordination of the resin flow process based on the adaptive closed-loop control of model prediction and visual feedback, thereby effectively preventing internal defects such as dry spots or air bags caused by uncoordinated flow, and greatly improving the process success rate and the quality uniformity and reliability of the composite material product.

Description

Technical Field

[0001] This application belongs to the field of liquid molding technology, and in particular relates to a resin injection process control method and control system. Background Technology

[0002] Vacuum-assisted resin infusion is a key process for manufacturing large composite components. In this process, resin fills a mold cavity rich in fiber preforms under pressure differential. To facilitate resin flow, flow channels are often pre-designed on the mold surface. However, when the resin simultaneously flows through different regions with significantly different permeabilities, its flow front morphology becomes complex and difficult to predict.

[0003] In related technologies, control methods often rely on the operator's experience and observation, or on simple pre-set programs based on the assumption of idealized uniform flow. These methods cannot perceive and respond to the dynamic changes in the actual flow state in real time and accurately, resulting in uncoordinated resin flow within the mold. This easily leads to defects such as localized unwetting, dry spots, or closed air pockets, seriously affecting the quality stability and yield of the product. This problem is particularly prominent for complex structural parts.

[0004] Therefore, the industry urgently needs a resin injection control method that can more accurately describe flow behavior and achieve intelligent closed-loop regulation. Summary of the Invention

[0005] This application provides a resin infusion process control method and control system. Based on model prediction and visual feedback adaptive closed-loop control, it realizes precise and proactive coordination of the resin flow process, thereby effectively preventing internal defects such as dry spots or air pockets caused by flow incoordination, and significantly improving the process success rate and the quality uniformity and reliability of composite material products.

[0006] In a first aspect, the embodiments of this application provide a resin injection process control method, applied to a controller in a resin injection process control system. The resin injection process control system further includes an injection mold, an injection device, a vacuum pump, and an image acquisition device. The controller is connected to the injection device, the vacuum pump, and the image acquisition device, respectively. The control method includes: Obtain mold structure parameters, fiber preform permeability, and resin viscosity of the resin to be injected; During the resin injection process, the air pressure value inside the mold cavity and the image sequence collected during the injection process are obtained. The image acquisition period in the image sequence is determined according to the characteristics of the resin and the injection process parameters. Based on the mold structure parameters, fiber preform permeability and resin viscosity, combined with the air pressure value in the mold cavity, the theoretical predicted position of the resin flow front is calculated by a dual-zone parallel permeability model; the dual-zone parallel permeability model is used to describe the parallel flow of resin in the groove channel region and the fiber preform region of the mold cavity. The image sequence is processed to identify the actual location of the resin flow front; The actual location is compared with the theoretically predicted location to obtain the comparison results; Based on the comparison results, the injection flow rate of the injection device and / or the vacuum level of the vacuum pump are adjusted in real time. The vacuum level of the vacuum pump is negatively correlated with the air pressure value in the mold cavity.

[0007] In some embodiments, adjusting the dispensing flow rate of the dispensing device and / or the vacuum level of the vacuum pump in real time based on the comparison results includes: If the actual position lags behind the theoretically predicted position, and the lag distance is greater than or equal to the first threshold, increase the dispensing flow rate of the dispensing device and / or increase the vacuum level of the vacuum pump. If the actual position is ahead of the theoretically predicted position, and the lead distance is greater than or equal to the second threshold, reduce the dispensing flow rate of the dispensing device and / or reduce the vacuum level of the vacuum pump.

[0008] In some embodiments, the control method further includes: If the flow front position in the groove channel area is found to be ahead of the wetting front position in the fiber preform area, and the distance between the flow front position and the wetting front position exceeds the third threshold, the glue injection device is controlled to switch to pulse glue injection mode.

[0009] In some embodiments, the control method further includes: When the viscosity of the resin to be injected is less than or equal to the set viscosity threshold, the dual-zone parallel permeability model is corrected by introducing a first inertia correction factor. The theoretically predicted location of the resin flow front was recalculated based on the modified dual-zone parallel permeability model.

[0010] In some embodiments, the control method further includes: Based on the image sequence, the unfilled sub-regions in the fiber preform area are continuously tracked within the identified resin flow front region; If an unfilled sub-region is surrounded by a filled trench channel region, and the unfilled sub-region remains unfilled for a duration exceeding a set time threshold, perform at least one of the following measures: Switch the dispensing device to pulse dispensing mode; During the resin injection phase of the pulse dispensing mode, the dispensing flow rate is increased from the current reference flow rate to the set flow rate; Increase the vacuum level of the vacuum pump from the current reference vacuum level to the set vacuum level.

[0011] In some embodiments, the control method further includes: Each frame of the image sequence is identified to determine the resin filling rate corresponding to each frame. The filling change rate is determined based on the resin filling rate and timestamp information corresponding to each frame image; If the resin filling rate corresponding to the current frame image is less than or equal to the fourth threshold, and the filling change rate is greater than or equal to the fifth threshold, reduce the glue injection flow rate of the glue injection device and / or reduce the vacuum degree of the vacuum pump.

[0012] In some embodiments, the control method further includes: If the resin filling rate corresponding to the current frame image is greater than or equal to the sixth threshold and the filling change rate is less than or equal to the seventh threshold, increase the glue injection flow rate of the glue injection device and decrease the vacuum degree of the vacuum pump. The seventh threshold is less than the fifth threshold.

[0013] In some embodiments, the control method further includes: If the resin filling rate corresponding to the current frame image is greater than or equal to the eighth threshold and the filling change rate is less than or equal to the ninth threshold, the image acquisition cycle of the image acquisition device is increased, and the ninth threshold is less than the fifth threshold.

[0014] Secondly, embodiments of this application also provide a resin infusion process control system, including: The injection mold includes a platform, a mold assembly, and a transparent sealing assembly. The mold assembly is placed on the platform, and the transparent sealing assembly covers the mold assembly and together with the mold assembly forms a sealed space. The mold assembly includes a molding die and a fiber preform. The surface of the molding die has a preset microchannel structure, and the fiber preform covers the microchannel structure to form a mold cavity. The resin injection device is connected to the mold cavity through the resin injection port and is configured to inject resin into the mold cavity; A vacuum pump, connected to the mold cavity through a dispensing port, is configured to extract air from the sealed space to create a vacuum; An image acquisition device is located on the side of the mold assembly away from the platform and is configured to acquire a sequence of images of the resin being poured into the mold cavity. The image acquisition period in the image sequence is determined according to the characteristics of the resin and the pouring process parameters. The controller, connected to the glue injection device, vacuum pump, and image acquisition device, is configured to: acquire mold structure parameters, fiber preform permeability, and resin viscosity; acquire the air pressure value inside the mold cavity and the image sequence acquired during the resin injection process; calculate the theoretical predicted position of the resin flow front using a dual-zone parallel permeability model based on the mold structure parameters, fiber preform permeability, and resin viscosity, combined with the air pressure value inside the mold cavity; wherein the dual-zone parallel permeability model is used to describe the parallel flow of resin in the groove channel region and the fiber preform region of the mold cavity; process the image sequence to identify the actual position of the resin flow front; compare the actual position with the theoretical predicted position, and adjust the glue injection flow rate of the glue injection device and / or the vacuum degree of the vacuum pump in real time according to the comparison result, wherein the vacuum degree of the vacuum pump is negatively correlated with the air pressure value inside the mold cavity.

[0015] In some embodiments, the outlet is located at the end of the mold cavity, and the distance between the outlet and the mold cavity is greater than a set distance.

[0016] In some embodiments, the microchannel structure includes a polygonal microgroove structure.

[0017] The resin infusion process control method and control system provided in this application introduce a dual-zone parallel permeability model to accurately describe the parallel flow characteristics of resin in the groove channel and fiber preform, breaking the prediction bias caused by the traditional single model ignoring regional differences; and based on model prediction and visual feedback adaptive closed-loop control, it fundamentally overcomes the blindness and lag of traditional control that relies on experience or fixed program control, and realizes fine and proactive coordination of the resin flow process, thereby effectively preventing internal defects such as dry spots or air pockets caused by flow incoordination, and greatly improving the process success rate and the quality uniformity and reliability of composite material products. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of a resin infusion process control system provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of the injection mold provided in the embodiment of this application; Figure 3 This is a schematic diagram of another resin infusion process control system provided in an embodiment of this application; Figure 4 This is a schematic diagram illustrating the working principle of the pneumatic control device provided in the embodiments of this application; Figure 5 This is a schematic diagram of the resin flow path within the flow channel provided in the embodiments of this application; Figure 6 This is a schematic flowchart of a resin infusion process control method provided in an embodiment of this application; Figure 7 This is a schematic diagram of a frame image obtained during the resin injection process in the mold cavity, as provided in an embodiment of this application. Figure 8 This is a schematic flowchart of another resin infusion process control method provided in the embodiments of this application; Figure 9 This is a schematic diagram of the structure of a controller provided in an embodiment of this application. Detailed Implementation

[0020] The features and exemplary embodiments of various aspects of this application will be described in detail below. To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain this application and not to limit it. For those skilled in the art, this application can be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of this application by illustrating examples.

[0021] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0022] To address the problems raised in the background art, this application provides a resin infusion process control method and control system. It introduces a dual-zone parallel permeability model to accurately describe the parallel flow characteristics of resin in the grooved channels and fiber preforms, overcoming the prediction bias caused by the traditional single model ignoring regional differences. Based on model prediction and visual feedback-based adaptive closed-loop control, it fundamentally overcomes the blindness and lag of traditional experience-based or fixed-program control, achieving precise and proactive coordination of the resin flow process. This effectively prevents internal defects such as dry spots or air pockets caused by flow incoordination, significantly improving the process success rate and the quality uniformity and reliability of composite material products.

[0023] The resin infusion process control system provided in the embodiments of this application will be described below.

[0024] Figure 1 This is a schematic diagram of the structure of a resin infusion process control system provided in an embodiment of this application. Figure 1 As shown, the resin injection process control system 10 may include: injection mold 11, injection device 12, vacuum pump 13, image acquisition device 14, and controller 15.

[0025] Among them, combined Figure 2 The injection mold 11 includes a platform 111, a mold assembly 112, and a transparent sealing assembly 113. The mold assembly 112 is placed on the platform 111, and the transparent sealing assembly 113 covers the mold assembly 112 and together with the mold assembly 112 forms a sealed space. The mold assembly 112 includes a molding mold 1121 and a fiber preform 1122. The surface of the molding mold 1121 has a preset microchannel structure 1123, and the fiber preform 1122 covers the microchannel structure 1123 to form a mold cavity.

[0026] For example, such as Figure 2 As shown, the transparent sealing assembly 113 includes a transparent vacuum bag 1131 and a sealing strip 1132. The transparent vacuum bag 1131 covers the molding mold 1121 and the fiber preform 1122. The edge of the transparent vacuum bag 1131 is sealed by the sealing strip 1132 to form a sealed space.

[0027] The resin injection device 12 is connected to the mold cavity through the injection port and is configured to inject resin into the mold cavity. The resin injection device 12 can be any type of resin injection device known to those skilled in the art, such as a high-precision peristaltic pump resin injection device, a screw-type metering resin injection device, an injection-type resin injection device, and an integrated intelligent resin injection system, and is not limited herein.

[0028] The vacuum pump 13 is connected to the mold cavity through the glue outlet and is configured to extract air from the sealed space to form a vacuum.

[0029] The injection port is located at the beginning of the mold cavity, and the outlet is located at the end of the mold cavity.

[0030] This application does not limit the form of the dispensing port. For example, a straight-through dispensing port or a diffusion dispensing port can be used. The straight-through dispensing port can be used for single-point dispensing or multi-point matrix dispensing. For example, taking the diffusion dispensing port as an example, the outlet end of the dispensing port is in a "trumpet shape" with a diffusion angle of 30°~60°. The inner wall is smooth and the outlet edge is rounded. A transverse guide groove is provided at the outlet end, and a spiral tube is provided in the guide groove. The resin is evenly distributed to the inlet end of the microchannel structure through the spiral tube.

[0031] This application does not limit the form of the dispensing port. For example, a straight-through dispensing port or a flared dispensing port can be used. The straight-through dispensing port can use single-point dispensing or multi-point matrix dispensing. For example, taking the flared dispensing port as an example, the inlet end of the dispensing port is flared in a "trumpet" shape with a diffusion angle of 45°~60°. The rear end connects to the straight section. The inner wall of the flared port is smoothed, and the inlet edge is rounded.

[0032] The image acquisition device 14 is disposed on the side of the mold assembly 112 away from the stage 111, and is configured to acquire a sequence of images of the resin during the pouring process within the mold cavity. The image acquisition period in the image sequence is determined according to the characteristics of the resin and the pouring process parameters. The image acquisition device 14 may include any device with image acquisition function known to those skilled in the art, such as a high-speed acquisition camera, and is not limited herein. The image acquisition device 14 can be vertically arranged above the pouring mold via a fixed bracket, and captures the flow behavior of the resin within the microchannels during the pouring process from top to bottom through the transparent sealing assembly 113.

[0033] The controller 15 is connected to the glue injection device 12, the vacuum pump 13, and the image acquisition device 14. The controller 15 is configured to: acquire mold structure parameters, fiber preform permeability, and resin viscosity; acquire the air pressure value inside the mold cavity and the image sequence acquired during the resin injection process; calculate the theoretical predicted position of the resin flow front using a dual-zone parallel permeability model based on the mold structure parameters, fiber preform permeability, and resin viscosity, combined with the air pressure value inside the mold cavity; wherein, the dual-zone parallel permeability model is used to describe the parallel flow of resin in the groove channel region and the fiber preform region of the mold cavity; process the image sequence to identify the actual position of the resin flow front; compare the actual position with the theoretical predicted position, and adjust the glue injection flow rate of the glue injection device 12 and / or the vacuum degree of the vacuum pump 13 in real time according to the comparison result, wherein the vacuum degree of the vacuum pump is negatively correlated with the air pressure value inside the mold cavity.

[0034] The fluid flow channel consists of two regions with significantly different physical properties: the groove channel region and the fiber preform region. The groove channel region has high permeability and low flow resistance, playing a dominant role in flow; while the fiber preform region has a dense internal structure, low porosity, and poor permeability, making it the main limiting factor for flow rate. The dual-zone parallel permeability model treats the groove channel region and the fiber preform region as parallel flow paths driven by the same pressure difference. The flow rate is distributed according to the flow resistance of each path, and the equivalent permeability of the system is calculated using an area-weighted average.

[0035] The resin infusion process control system provided in this application provides stable hardware support for the control method. The transparent sealing component 113 meets the image acquisition requirements, the microchannel structure 1123 is precisely matched with the dual-zone parallel permeability model, and the controller 15 coordinates data processing and parameter adjustment to achieve full-chain collaboration from hardware to software. By introducing the dual-zone parallel permeability model, the parallel flow characteristics of resin in the groove channel and fiber preform are accurately described, breaking the prediction bias caused by the traditional single model ignoring regional differences. Based on model prediction and visual feedback, the adaptive closed-loop control fundamentally overcomes the blindness and lag of traditional control that relies on experience or fixed program control, and realizes fine and proactive coordination of the resin flow process. This effectively prevents internal defects such as dry spots or air pockets caused by flow incoordination, and greatly improves the process success rate and the quality uniformity and reliability of composite material products.

[0036] In some embodiments, such as Figure 3 As shown, the resin infusion process control system may also include a resin recovery tank 16 and a pressure sensor 17.

[0037] The resin recovery tank 16 is connected to the glue outlet and is used to collect the excess resin discharged from the glue outlet. On the one hand, it avoids resin waste and reduces production costs. On the other hand, it uses the space inside the tank to separate the resin from the air, preventing the resin from entering the vacuum pump with the airflow and causing equipment damage. Moreover, the sealed space of the resin recovery tank 16 can buffer the pressure fluctuations when the vacuum pump is pumping air, and prevent sudden changes in air pressure from affecting the stable flow field in the mold cavity.

[0038] A pressure sensor 17 is connected between the vacuum pump 13 and the resin recovery tank 16 to continuously collect the pressure value between them, directly providing feedback on the actual pressure state within the mold cavity. Figure 4 The pressure sensor 17 is also connected to the controller 15 to transmit the pressure value data to the controller 15.

[0039] In some embodiments, such as Figure 3 As shown, the resin infusion process control system may also include a host computer 18.

[0040] The host computer 18 provides an operating interface for users, allowing them to input or adjust mold structure parameters, fiber preform permeability and resin viscosity, as well as various control thresholds.

[0041] The host computer 18 is also used to analyze and identify image sequences, determine the actual position of the resin flow front and calculate the filling rate / filling change rate. At the same time, it runs a dual-zone parallel permeability model, and calculates the theoretical predicted position of the flow front by combining mold parameters and resin viscosity data, providing a core basis for regulation.

[0042] The host computer 18 is also used to send instructions to the controller based on the comparison results between the actual position and the theoretically predicted position, as well as the filling rate status / fill change rate status, serving as a bridge to realize human-computer interaction and automatic control.

[0043] The host computer 18 also has a visual monitoring function, which can simultaneously display real-time process parameters such as the air pressure value in the mold cavity, the injection flow rate, and the vacuum degree of the vacuum pump. It can generate curves such as the filling rate-time, the filling change rate-time, and the vacuum degree-time, which can intuitively present the status of the injection process.

[0044] The host computer 18 also has data storage and traceability functions, recording image sequences, process parameters, control operation logs and other data throughout the entire pouring process, which facilitates subsequent review of process defects and optimization of parameters, meeting the process traceability requirements of mass production scenarios.

[0045] The host computer 18 also has an abnormal alarm function. When parameters such as air pressure, filling rate, and flow front deviation exceed preset thresholds, a visual alarm (such as a pop-up window or parameter highlighting) is triggered to remind the user to intervene in time and ensure injection safety and quality.

[0046] In some embodiments, such as Figure 4 As shown, the resin infusion process control system may also include a venting valve 191 and an extraction valve 192.

[0047] Both the venting valve 191 and the suction valve 192 are connected to the controller 15. The venting valve 191 responds to controller commands by adjusting its opening degree to controllably release pressure in the mold cavity, thereby reducing the vacuum level of the vacuum pump 13 and preventing turbulence in the resin flow front caused by a sudden drop in pressure. The suction valve 192 responds to controller commands to precisely start and stop the suction circuit. Through graded control of the valve opening degree, combined with the adjustment of the output power of the vacuum pump 13, it achieves stepless adjustment of the vacuum level to meet the pressure requirements of different filling stages.

[0048] In some embodiments, the outlet is located at the end of the mold cavity, and the distance between the outlet and the mold cavity is greater than a set distance.

[0049] In this embodiment, the distance between the injection port and the end of the mold cavity can be flexibly set according to the size of the mold component, with a distance range of 2cm to 10cm.

[0050] In this embodiment, the outlet and the end of the mold cavity are spaced apart, so that the distance between them is greater than a set distance. This effectively prevents the resin from flowing directly to the outlet channel at the end of the cavity instead of fully impregnating the fiber preform. By reasonably setting the outlet distance, the resin is guided to preferentially impregnate the fiber area, thereby improving the molding quality and process stability of the part.

[0051] In some embodiments, such as Figure 5 As shown, the microchannel structure 1123 includes a polygonal microgroove structure.

[0052] In this process, polygonal units 1124 with a preset spatial distribution are set on the surface of the molding die. There is a gap between each pair of adjacent polygonal units 1124, and all gaps are connected to form a polygonal groove structure (i.e., microchannel structure 1123), which serves as a resin flow channel during the resin injection process.

[0053] The polygonal microgroove structure may include any polygonal microgroove structure known to those skilled in the art, such as a triangular microgroove structure, a quadrilateral microgroove structure, or a hexagonal microgroove structure.

[0054] This embodiment utilizes the high space utilization and uniform flow characteristics of polygons (e.g., hexagons) to provide a stable path for resin flow in the groove channel area. The polygonal microgrooves can guide the resin to spread evenly, avoid sudden changes in local flow velocity, and adapt to the parallel flow characteristics of dual zones, promoting resin penetration into the fiber preform area. Compared with traditional irregular channels, it has stronger structural stability, reduces channel blockage caused by fiber preform extrusion, and improves the uniformity of resin flow and wetting.

[0055] As an example, such as Figure 5 As shown, the polygonal microgroove structure includes hexagonal microgroove structures, with the corresponding polygonal unit 1124 being a hexagonal unit. The hexagonal microgroove structure includes regular hexagonal microgroove structures, with the corresponding polygonal unit being a regular hexagonal unit. A regular and interconnected microchannel network is formed between the hexagonal units. This microchannel network guides the resin to preferentially expand along the groove region, making the flow path (as shown by the solid arrow) stable and directional. The gaps between the hexagonal units provide a channel for residual air inside the mold to escape (as shown by the short arrow), thereby effectively suppressing the generation of molding defects such as voids. The hexagonal microgroove structure not only improves the uniformity and controllability of resin flow but also facilitates fiber wetting in complex preforms. The arrangement of the hexagonal columnar structures significantly increases the interfacial contact area, thereby improving interfacial bonding performance and further enhancing the density and overall mechanical properties of the composite material.

[0056] Next, the resin infusion process control method provided in the embodiments of this application will be described.

[0057] The resin injection process control method provided in this application is applied to the controller in the resin injection process control system. The resin injection process control system also includes an injection mold, an injection device, a vacuum pump, and an image acquisition device. The controller is connected to the injection device, the vacuum pump, and the image acquisition device, respectively.

[0058] like Figure 6 As shown, the control method includes the following steps: S110~S160.

[0059] S110. Obtain mold structure parameters, fiber preform permeability, and resin viscosity of the resin to be injected.

[0060] The mold structure parameters may include the width of the flow channel, the side length of the polygonal unit, and the channel surface density. Channel surface density refers to the ratio of the flow channel area to the total area of ​​the pattern layer on the molding die. The width of the flow channel and the side length of the polygonal unit affect the channel surface density.

[0061] The fiber preform permeability may include the first fiber permeability of the polygonal unit region and the second fiber permeability of the flow channel region (i.e., the groove flow region).

[0062] S120. During the resin injection process, acquire the air pressure value inside the mold cavity and the image sequence collected during the injection process.

[0063] In this step, during resin injection, the air pressure value inside the mold cavity is obtained through an air pressure sensor. Based on the air pressure value inside the mold cavity and the standard atmospheric pressure, the pressure difference between the injection port and the outlet is obtained. During resin injection, an image acquisition device acquires image sequences and transmits the acquired image sequences to the controller.

[0064] The image acquisition cycle in the image sequence is determined based on the characteristics of the resin and the injection process parameters.

[0065] The higher the viscosity of the resin to be injected, the greater the flow resistance, and the longer the corresponding image acquisition period, i.e., the lower the acquisition frequency; the lower the viscosity of the resin to be injected, the lower the flow resistance, and the more frequent the corresponding image acquisition period, i.e., the higher the acquisition frequency.

[0066] The larger the size (e.g., length) of the molding die, the longer the flow channel, the greater the flow resistance, and the longer the corresponding image acquisition cycle, i.e., the lower the acquisition frequency; the smaller the size of the molding die, the shorter the flow channel, the lower the flow resistance, and the shorter the corresponding image acquisition cycle, i.e., the higher the acquisition frequency.

[0067] S130. Based on the mold structure parameters, fiber preform permeability and resin viscosity, combined with the air pressure value in the mold cavity, the theoretical predicted position of the resin flow front is calculated by a dual-zone parallel permeability model.

[0068] The dual-zone parallel permeability model is used to describe the parallel flow of resin in the groove channel region and the fiber preform region of the mold cavity. The fluid flow channel consists of two regions with significantly different physical properties: the groove channel region and the fiber preform region. The groove channel region has high permeability and low flow resistance, playing a dominant role in flow; while the fiber preform region has a dense internal structure, low porosity, and poor permeability, which is the main limiting factor for flow rate.

[0069] The dual-zone parallel permeability model treats the grooved channel region and the fiber preform region as parallel flow paths driven by the same pressure difference. The flow rate is distributed according to the flow resistance of each path, and the equivalent permeability of the system is calculated using an area-weighted average. The dual-zone parallel permeability model can predict the theoretical location of the resin movement front and also the injection filling time.

[0070] For example, the derivation process of the dual-zone parallel penetration rate model is as follows: To reflect the proportion of the gully channel area in the overall structure, channel surface density is introduced. The area of ​​the grooves in the mold is the proportion of the total area occupied by the grooves. It can be expressed by formula (1) for the channel surface density. .

[0071] (1) in, Represents the area of ​​a polygonal unit. Indicates the area of ​​the flow channel. This indicates the area of ​​the entire pattern layer on the molding die.

[0072] Based on the assumption of dual-zone parallel operation, the system's equivalent penetration rate As shown in formula (2).

[0073] (2) in, The first fiber permeability represents the polygonal unit region. The second fiber permeability represents the flow channel region (i.e., the gully flow region).

[0074] Substituting Darcy's law further, the volumetric flow rate expression for the parallel system is shown in formula (3).

[0075] (3) in, , representing the pressure gradient per unit length. This indicates the pressure difference between the resin flow front and the injection port. This indicates the filling distance, which is the distance between the resin flow front and the starting point of the injection. Indicates resin viscosity. This represents the cross-sectional area of ​​resin flow, including the cross-sectional area of ​​resin in the groove channel region and the cross-sectional area of ​​resin in the fiber preform region.

[0076] Based on the relationship between volumetric flow velocity and cross-sectional area Then, with the fill distance Fill time Definition Combining these, we obtain formula (4).

[0077] (4) Further derivation of the infusion filling time The expression is shown in formula (5).

[0078] (5) Substituting the length of the molding die into formula (5), the predicted filling time required to complete resin infusion can be obtained by calculation.

[0079] Alternatively, by transforming and deriving formula (5), the filling distance can be obtained. The expression is shown in formula (6).

[0080] (6) Substituting the injection time corresponding to the current moment into formula (6), the distance between the resin flow front and the injection start end corresponding to the current moment can be calculated, thereby determining the theoretical predicted position of the resin flow front.

[0081] S140. Process the image sequence to identify the actual position of the resin flow front.

[0082] Figure 7This image, captured during the resin injection process within the mold cavity, illustrates an application embodiment. In areas where the fiber preform is not resin-impregnated, air remains between the preform and the pattern layer. Due to the refractive index difference between the air and the preform, light scattering occurs, resulting in a white area where the resin cannot transmit the color of the injection mold. In areas where the fiber preform is fully resin-impregnated, the space between the preform and the pattern layer is filled with resin. The refractive index of the resin is closer to that of the preform, reducing scattering and making the preform more transparent, allowing the resin to transmit the color of the injection mold. This transformation of optical phenomena provides a basis for visual judgment of the wetting process. The wetting state of the fiber preform can be determined based on its color, thereby determining the resin filling state.

[0083] In this step, by recognizing multiple frames of images in the image sequence, the boundary between the resin-filled area and the unfilled area is identified by utilizing the color difference presented by the fiber preform in the wetted and unwetted states, thereby determining the actual position of the resin flow front.

[0084] S150. Compare the actual location with the theoretically predicted location to obtain the comparison result.

[0085] The comparison results between the actual location and the theoretical prediction location include: the actual location is ahead of the theoretical prediction location, the actual location is behind the theoretical prediction location, and the actual location coincides with or is close to the theoretical prediction location.

[0086] S160. Based on the comparison results, adjust the dispensing flow rate of the dispensing device and / or the vacuum level of the vacuum pump in real time.

[0087] The vacuum level of the vacuum pump is negatively correlated with the gas pressure inside the mold cavity. Increasing the vacuum level of the vacuum pump will decrease the gas pressure inside the mold cavity; decreasing the vacuum level of the vacuum pump will increase the gas pressure inside the mold cavity.

[0088] Increasing the flow rate of the glue dispensing device can increase the air pressure at the dispensing port; decreasing the flow rate of the glue dispensing device can decrease the air pressure at the dispensing port.

[0089] In this step, control strategies are implemented in a targeted manner based on the specific comparison results between the actual location and the theoretically predicted location.

[0090] When the actual position lags behind the theoretically predicted position, the pressure difference between the resin flow front and the injection port can be increased by increasing the injection flow rate of the injection device and / or increasing the vacuum level of the vacuum pump. This increases the driving force of resin flow, accelerating the actual position of the resin flow front to catch up with the theoretically predicted position.

[0091] When the actual position precedes the theoretically predicted position, the pressure difference between the resin flow front and the injection port can be reduced by decreasing the injection flow rate of the injection device and / or reducing the vacuum level of the vacuum pump. This reduces the driving force of resin flow, slows down the actual position of the resin flow front, and returns it to the theoretically predicted position.

[0092] If the actual location coincides with or is close to the theoretically predicted location, the current infusion parameters can be maintained without adjustment.

[0093] The resin infusion process control method provided in this application introduces a dual-zone parallel permeability model to accurately describe the parallel flow characteristics of resin in the groove channel and fiber preform, breaking the prediction bias caused by the traditional single model ignoring regional differences. Based on model prediction and visual feedback, the adaptive closed-loop control fundamentally overcomes the blindness and lag of traditional control relying on experience or fixed programs, achieving fine and proactive coordination of the resin flow process. This effectively prevents internal defects such as dry spots or air pockets caused by flow incoordination, significantly improving the process success rate and the quality uniformity and reliability of composite material products.

[0094] In some embodiments, such as Figure 8 As shown, S160 may include the following steps: S161~S162.

[0095] S161. When the actual position lags behind the theoretically predicted position, and the lag distance is greater than or equal to the first threshold, increase the dispensing flow rate of the dispensing device and / or increase the vacuum degree of the vacuum pump.

[0096] When the actual position lags significantly behind the theoretically predicted position, it indicates insufficient actual flow driving force, resulting in slow resin propagation in the groove channel region. Increasing the injection flow rate of the injection device can raise the air pressure at the small injection port; increasing the vacuum level of the vacuum pump can lower the air pressure inside the mold cavity. Both of these measures can increase the pressure difference between the resin's moving front and the injection port. This increases the driving force of resin flow, thereby increasing the resin flow velocity and accelerating the actual position of the resin flow front to catch up with the theoretically predicted position.

[0097] S162. When the actual position is ahead of the theoretically predicted position and the lead distance is greater than or equal to the second threshold, reduce the dispensing flow rate of the dispensing device and / or reduce the vacuum degree of the vacuum pump.

[0098] When the actual position significantly exceeds the theoretically predicted position, it indicates that the actual flow driving force is too large, causing the resin to advance rapidly in the groove channel region. Due to the velocity difference between the two zones, the fiber preform region is not sufficiently wetted, and the excessively high flow rate prevents timely air removal, leading to the formation of air bubbles or closed air pockets. Reducing the resin injection flow rate of the injection device can lower the air pressure at the injection port; reducing the vacuum level of the vacuum pump can increase the air pressure within the mold cavity. Both of these measures can reduce the pressure difference between the resin's moving front and the injection port. This reduces the driving force of resin flow, thereby reducing the resin flow rate and slowing down the actual position of the resin flow front, bringing it back to the rhythm of the theoretically predicted position.

[0099] The resin infusion process control method provided in this application can enhance the resin flow driving force by increasing the resin flow rate of the injection device and / or the vacuum degree of the vacuum pump when the actual position of the resin flow front is lagging behind, thereby accelerating the actual position of the resin flow front to catch up with the theoretically predicted position. When the actual position of the resin flow front is ahead, the driving force of the resin flow is reduced by decreasing the resin flow rate of the injection device and / or the vacuum degree of the vacuum pump, thereby reducing the resin flow velocity. This can suppress defects such as front-end disturbance and insufficient fiber wetting caused by excessively fast flow, slowing down the actual position of the resin flow front and returning it to the rhythm of the theoretically predicted position. By using a threshold triggering combined with precise fine-tuning, over-regulation or under-regulation is avoided, achieving a dynamic balance of resin flow rate and adapting to the flow requirements of different infusion stages. At the same time, the lag distance threshold (i.e., the first threshold) and the lead distance threshold (i.e., the second threshold) are quantified, making parameter adjustment more targeted and operable.

[0100] In some embodiments, the control method may further include the following steps: when it is detected that the flow front position of the groove channel region is ahead of the wetting front position of the fiber preform region, and the distance between the flow front position and the wetting front position exceeds a third threshold, the glue injection device is controlled to switch to pulse glue injection mode.

[0101] There are significant differences in the flow rate and permeability of the resin in the groove channel region and the fiber preform region under the same pressure differential. In the grooved channel region, the resin propulsion rate is much greater than the impregnation rate of the fiber preform region, resulting in the flow front position of the grooved channel region being ahead of the impregnation front position of the fiber preform region.

[0102] When the flow front in the grooved channel region precedes the wetting front in the fiber preform region, and the distance between them exceeds the third threshold, the underlying reason is that the flow driving force under continuous glue injection remains high, causing the velocity difference between the two regions to continue to widen. Simultaneously, the persistently high pressure difference... This can easily lead to the formation of jet or turbulent flow of resin in the groove channel area. The high-speed impact of the resin on the surface of the fiber preform not only disrupts the fiber arrangement and causes local pore blockage, but also traps air into the fiber gaps, forming closed bubbles, which further hinders the wetting of the fiber area and exacerbates the separation of the two zones.

[0103] Pulse-type glue injection mode refers to intermittent glue injection, periodically alternating between glue injection and pausing glue injection operations.

[0104] Pulsed injection breaks the constant high pressure differential of continuous injection, causing the driving pressure to fluctuate periodically. This allows for differentiated control of the flow velocity in the two zones. During the injection phase, the pressure differential increases, and the resin in the groove channel region advances rapidly, while simultaneously providing instantaneous high-permeability driving force for the fiber zone. During the pause injection phase, the pressure differential decreases to the baseline value (or even partially depressurizes), the resin in the groove channel region stops advancing, and the flow field tends to stabilize. Meanwhile, the fiber preform region utilizes the pause time to complete unsteady-state permeation under the drive of the remaining pressure differential, and the wetting rate gradually increases. By periodically adjusting the pressure differential, the advancement in the groove channel region and the permeation in the fiber preform region are periodically matched, gradually narrowing until the leading edge spacing falls back to within the third threshold, thus meeting the cooperative flow requirements of the dual-zone parallel model.

[0105] The resin infusion process control method provided in this application embodiment utilizes the intermittent rhythm of pulsed injection "injection-pause injection" to break the inertia of the resin flow rapidly advancing along the flow channel, allowing sufficient time for the resin to penetrate into the fiber preform, effectively reducing the distance between the leading edges of the two regions, and solving the problem of "fast flow channel, slow wetting" disconnection that is easily caused by traditional continuous injection, so that the resin and fiber are fully combined, which is beneficial to improving the interlayer mechanical properties of the part.

[0106] In some embodiments, the control method may further include the following steps: when the resin viscosity of the resin to be injected is less than or equal to a set viscosity threshold, the dual-zone parallel permeability model is corrected by introducing a first inertia correction factor; and the theoretical predicted position of the resin flow front is recalculated based on the corrected dual-zone parallel permeability model.

[0107] The first inertia correction factor is determined by the mold structure parameters, which may include the width of the flow channel and the side length of the polygonal unit.

[0108] For example, when the resin viscosity is less than or equal to 350 cP, the corresponding first inertia correction factor is... The expression is shown in formula (7).

[0109] (7) Introducing the first inertia correction factor Then, the expression for the dual-zone parallel permeability model is shown in formula (8) or formula (9).

[0110] (8) (9) The resin infusion process control method provided in this application introduces a first inertia correction factor to dynamically correct the dual-zone parallel permeability model. The corrected model can more accurately reflect the flow law of resin in the "flow channel advance - wetting lag" state, making the theoretical prediction position more consistent with the actual state, providing a reliable basis for subsequent parameter adjustment, avoiding control mismatch caused by inaccurate model prediction, and further improving the accuracy and stability of closed-loop control.

[0111] In some embodiments, the control method may further include the following steps: when the resin viscosity of the resin to be injected is greater than a set viscosity threshold, the dual-zone parallel permeability model is corrected by introducing a second inertia correction factor; and the theoretical predicted position of the resin flow front is recalculated based on the corrected dual-zone parallel permeability model.

[0112] The second inertia correction factor is determined by the mold structure parameters, which may include the width of the flow channel and the side length of the polygonal unit.

[0113] For example, when the resin viscosity is greater than 350 cP, the corresponding second inertia correction factor The expression is shown in formula (10).

[0114] (10) The second inertia correction factor By replacing the first inertia correction factor in formula (8) or formula (9), the expression for the modified dual-zone parallel permeability model is obtained.

[0115] In some embodiments, the control method may further include the following steps: Based on the image sequence, the unfilled sub-regions in the fiber preform area are continuously tracked within the identified resin flow front region; If an unfilled sub-region is surrounded by a filled trench channel region, and the unfilled sub-region remains unfilled for a duration exceeding a set time threshold, perform at least one of the following measures: Switch the dispensing device to pulse dispensing mode; During the resin injection phase of the pulse dispensing mode, the dispensing flow rate is increased from the current reference flow rate to the set flow rate; Increase the vacuum level of the vacuum pump from the current reference vacuum level to the set vacuum level.

[0116] The unfilled sub-region, surrounded by the filled groove channel region within the fiber preform area, represents a typical closed dry spot or closed air pocket defect during resin infusion. The trigger condition is that the duration of the unfilled state exceeds a set time threshold, excluding cases of temporary enclosure. Temporary enclosure is self-healing; some small-scale enclosure areas can self-fill within a short time without external intervention.

[0117] Utilizing the intermittent rhythm of "injection-pause injection" in pulsed resin injection, the instantaneous injection of resin during the injection phase causes a short-term surge in local driving pressure, forming a momentary high-pressure pulse. This high pressure can instantly break the steady-state equilibrium between capillary resistance and the closed air pressure, propelling the resin into the fiber pores of the closed sub-region. During the pause injection phase, the local pressure drops, but driven by residual pressure, the resin continues to flow unsteadily into the sub-region along the already permeated pores. Simultaneously, air within the closed sub-region can be slowly discharged through the tiny channels formed by resin permeation, further reducing the pressure of the air pressure trap. Through multiple cycles of "high-pressure pulse-low-speed permeation," the resin achieves cumulative permeation into the closed sub-region, gradually filling the unfilled area while gradually discharging the closed air, ultimately breaking the air pressure trap and achieving complete filling of the sub-region.

[0118] In the local flow field of the closed sub-region, the injection flow rate is positively correlated with the local driving pressure of the resin. Increasing the injection flow rate can enhance the instantaneous pressure jump during the pulse injection phase, forming a higher-intensity high-pressure pulse. This not only quickly overcomes capillary resistance and sealing air pressure but also propels the resin into the deep pores of the closed sub-region, shortening the filling time. Increasing the flow rate only during the injection phase, rather than throughout the entire process, avoids excessively rapid resin advancement in the flow channel area caused by continuous high flow rates, preventing the formation of new enclosed sealing areas. Simultaneously, it allows for a smoother pressure drop during the pause phase, reserving sufficient time for resin permeation and air expulsion, achieving a balance between instantaneous enhanced driving force and stable permeation filling. This measure precisely enhances pulse injection, making the driving force of the high-pressure pulse more closely match the breaking-opening requirements of the closed sub-region, improving the penetration efficiency of a single pulse.

[0119] Increasing the vacuum level of the vacuum pump further reduces the pressure at the resin outlet of the mold cavity, increasing the overall driving pressure difference for resin injection. This increased pressure difference is directly transmitted to the periphery of the sealed sub-region, raising the basic driving pressure for resin penetration into the sub-region. It can also synergize with pulsed injection; the instantaneous high pressure of pulsed injection propels resin penetration, creating tiny channels that provide a path for air to escape from the sealed area. The increased vacuum level and the resulting pressure difference accelerate air expulsion. This creates a positive feedback loop of "resin penetration opening pathways - vacuum pressure relief and air expulsion," resulting in an exponential increase in the filling efficiency of the sealed sub-region.

[0120] The resin injection process control method provided in this application embodiment can accurately identify "closed airbag" defects. Through a combination of pulse injection, increased pulse injection flow rate, and increased vacuum, the unfilled sub-areas are targeted to be broken and filled. The impact effect of pulse injection can break the resin accumulation boundary around the airbag, and increasing the flow rate and vacuum can enhance the resin filling power and air removal efficiency, effectively avoiding structural defects in the parts caused by long-term airbag residue.

[0121] In some embodiments, the control method may further include the following steps: Each frame of the image sequence is identified to determine the resin filling rate corresponding to each frame. The filling change rate is determined based on the resin filling rate and timestamp information corresponding to each frame image; If the resin filling rate corresponding to the current frame image is less than or equal to the fourth threshold, and the filling change rate is greater than or equal to the fifth threshold, reduce the glue injection flow rate of the glue injection device and / or reduce the vacuum degree of the vacuum pump.

[0122] In this embodiment, the resin filling rate corresponding to each frame of the image is determined by recognizing the acquired images. Each frame of the image also carries timestamp information. Based on the filling rate and timestamp information corresponding to the current frame image and the previous frame image, the filling change rate can be obtained.

[0123] When the filling rate is less than or equal to the fourth threshold, it indicates that the process is in the early stage of filling. When the filling rate change is greater than or equal to the fifth threshold, it indicates that the resin flow rate is too fast. At this time, the cavity is not fully occupied. Excessive flow rate can easily cause defects such as air bubble entrainment and front-end disorder. By reducing the injection flow rate and / or adjusting the vacuum degree of the injection device, the resin is guided to spread smoothly, laying the foundation for subsequent uniform wetting. This achieves precise matching between the injection stage and parameter control, reducing the impact of initial defects on the overall quality of the part.

[0124] In some embodiments, "identifying each frame of an image sequence and determining the resin filling rate corresponding to each frame" may include the following steps: The observation area of ​​each frame image is divided into multiple first grid units to obtain the target image; wherein, the observation area is the projection area of ​​the mold cavity in each frame image; Perform image recognition on the target image to determine the number of cells to fill in the first grid cell; The resin filling rate is determined based on the number of first grid cells filled and the total number of first grid cells in the observation area.

[0125] Since the fiber preforms in the impregnated and unimpregnated areas exhibit different colors, the impregnated and unimpregnated areas can be distinguished based on color parameters (such as grayscale values), i.e., resin-filled and resin-unfilled areas can be distinguished. Based on image recognition technology, the filling state of each first grid cell in the observation area is identified. By counting the number of first grid cells with the filling state of "filled", the filling quantity of the first grid cell can be determined.

[0126] In some embodiments, "performing image recognition on the target image to determine the number of fill cells for the first grid cell" may include the following steps: Obtain the grayscale value of each first grid cell in the target image; If the gray value of the first grid cell is greater than or equal to the first gray value threshold, the filling state of the first grid cell is determined to be filled. The number of first grid cells to be filled is determined based on the number of first grid cells that are filled.

[0127] The first grid cell may include at least one pixel cell. By obtaining the gray value of each pixel cell in the first grid cell, the average gray value or the median gray value can be used as the gray value of the first grid cell.

[0128] In this embodiment, the comparison result between the gray value of the first grid cell and the first gray value threshold is used as the judgment basis, which can quickly complete the statistics of the filling quantity of the first grid cell. The ratio of the filling quantity of the first grid cell to the total number of the first grid cells in the observation area is used as the resin filling rate. The logic is simple and the operation is strong. Data can be output quickly without complex algorithms, taking into account both computational efficiency and basic accuracy.

[0129] In some embodiments, the fill state of the first grid cell includes fully filled, partially filled, and unfilled. (Combined) Figure 7 Unimpregnated fiber preforms appear white, and the first grid unit in this area corresponds to a smaller grayscale value. Fully impregnated fiber preforms have resin filling the space between the fiber preform and the pattern layer, which reduces light scattering and makes the fiber preform more transparent, allowing the color of the resin-filled mold to pass through. The first grid unit in this area corresponds to a larger grayscale value. Partially impregnated fiber preforms have a transparency level in between, and the first grid unit in this area also corresponds to a grayscale value in between.

[0130] "Performing image recognition on the target image to determine the number of fill cells for the first grid cell" may include the following steps: Obtain the grayscale value of each first grid cell in the target image; If the gray value of the first grid cell is greater than or equal to the second gray value threshold, the filling state of the first grid cell is determined to be fully filled, wherein the second gray value threshold is greater than the first gray value threshold. The number of fully filled first grid cells is determined based on the number of first grid cells that are fully filled. And, if the gray value of the first grid cell is greater than or equal to the first gray value threshold and less than the second gray value threshold, the filling state of the first grid cell is determined to be partially filled. The first grid cell, which is partially filled, is divided into multiple second grid cells; The number of cells to be filled in the second grid cell is determined based on the gray value of the second grid cell.

[0131] "Determining the resin filling rate based on the number of first grid cells filled and the total number of first grid cells in the observation area" may include the following steps: The area of ​​the resin-filled region is determined based on the number of fully filled first grid cells, the number of filled second grid cells, the area of ​​the first grid cell, and the area of ​​the second grid cell. The resin filling rate is determined based on the area of ​​the resin-filled region and the area of ​​the observation region.

[0132] In this embodiment, the filling state of the first grid unit is refined into fully filled, partially filled, and unfilled, which breaks through the limitation of the traditional binary judgment that ignores the partially filled area, accurately captures the transition state of the resin flow front, and further subdivides the partially filled first grid unit into a second grid unit to further explore the actual filling situation of the partially filled area, greatly reducing the calculation error caused by partial filling, realizing high-precision quantification of resin filling rate, and solving the problem of insufficient accuracy caused by ignoring partial filling in the traditional method.

[0133] In some embodiments, the control method may further include the following steps: when the resin filling rate corresponding to the current frame image is greater than or equal to a sixth threshold and the filling change rate is less than or equal to a seventh threshold, increasing the glue injection flow rate of the glue injection device and decreasing the vacuum degree of the vacuum pump, wherein the seventh threshold is less than the fifth threshold.

[0134] In this embodiment, when the resin filling rate corresponding to the current frame image is greater than or equal to the sixth threshold, it indicates that the filling is in the middle and late stages; when the filling change rate is less than or equal to the seventh threshold, it indicates that the resin flow rate has slowed down. This can be addressed by coordinating the increase of the injection flow rate of the injection device and the decrease of the vacuum degree of the vacuum pump. Increasing the injection flow rate can improve the end filling efficiency and avoid filling stagnation, while decreasing the vacuum degree can weaken the negative pressure traction and prevent air bubbles or edge defects caused by excessively fast resin flow at the end, thus balancing the filling efficiency and molding quality.

[0135] In some embodiments, the control method may further include the following steps: increasing the image acquisition cycle of the image acquisition device when the resin filling rate corresponding to the current frame image is greater than or equal to an eighth threshold and the filling change rate is less than or equal to a ninth threshold.

[0136] Among them, the ninth threshold is less than the fifth threshold.

[0137] In this embodiment, if the resin filling rate corresponding to the current frame image is greater than or equal to the eighth threshold, it indicates that the system is in the late stage of filling. If the filling change rate is less than or equal to the ninth threshold, it indicates that the resin flow rate has slowed down. At this time, high-frequency acquisition is not required to accurately monitor the status. By increasing the image acquisition cycle, data redundancy can be significantly reduced, the controller's computational load can be reduced, and the system's operating efficiency can be improved. At the same time, necessary monitoring accuracy is maintained to avoid control delays caused by excessive data, thus achieving a dynamic balance between monitoring accuracy and operating efficiency.

[0138] Figure 9 A schematic diagram of the hardware structure of the controller provided in an embodiment of this application is shown.

[0139] The controller may include a processor 901 and a memory 902 storing computer program instructions.

[0140] Specifically, the processor 901 may include a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits that can be configured to implement the embodiments of this application.

[0141] Memory 902 may include mass storage for data or instructions. For example, and not limitingly, memory 902 may include a hard disk drive (HDD), floppy disk drive, flash memory, optical disk, magneto-optical disk, magnetic tape, or Universal Serial Bus (USB) drive, or a combination of two or more of these. Where appropriate, memory 902 may include removable or non-removable (or fixed) media. Where appropriate, memory 902 may be internal or external to the controller. In a particular embodiment, memory 902 is a non-volatile solid-state memory.

[0142] Memory may include read-only memory (ROM), random access memory (RAM), disk storage media devices, optical storage media devices, flash memory devices, and electrical, optical, or other physical / tangible memory storage devices. Therefore, typically, memory includes one or more tangible (non-transitory) computer-readable storage media (e.g., memory devices) encoded with software including computer-executable instructions, and when the software is executed (e.g., by one or more processors), it is operable to perform the operations described with reference to the methods according to one aspect of this disclosure.

[0143] The processor 901 reads and executes computer program instructions stored in the memory 902 to implement any of the resin infusion process control methods in the above embodiments.

[0144] In one example, the controller may also include a communication interface 903 and a bus 904. Wherein, as... Figure 9 As shown, the processor 901, memory 902, and communication interface 903 are connected through bus 904 and complete communication with each other.

[0145] The communication interface 903 is mainly used to realize communication between various modules, devices, units and / or equipment in the embodiments of this application.

[0146] Bus 904 includes hardware, software, or both, that couples components of an online data flow metering device together. For example, and not limited to, the bus may include an Accelerated Graphics Port (AGP) or other graphics bus, an Enhanced Industry Standard Architecture (EISA) bus, a Front Side Bus (FSB), a Hypertext Transfer (HT) interconnect, an Industry Standard Architecture (ISA) bus, an Infinite Bandwidth Interconnect, a Low Pin Count (LPC) bus, a memory bus, a Micro Channel Architecture (MCA) bus, a Peripheral Component Interconnect (PCI) bus, a PCI-Express (PCI-X) bus, a Serial Advanced Technology Attachment (SATA) bus, a Video Electronics Standards Association Local Bus (VESA Local Bus, VLB) bus, or other suitable buses, or a combination of two or more of these. Where appropriate, bus 904 may include one or more buses. Although specific buses are described and illustrated in the embodiments of this application, this application considers any suitable bus or interconnection.

[0147] Furthermore, in conjunction with the resin filling rate determination method in the above embodiments, this application embodiment can provide a computer storage medium for implementation. This computer storage medium stores computer program instructions; when these computer program instructions are executed by a processor, they implement any of the resin filling process control methods in the above embodiments.

[0148] This application also provides a computer program product, including a computer program, which, when executed by a processor, implements any of the resin infusion process control methods described in the above embodiments.

[0149] It should be clarified that this application is not limited to the specific configurations and processes described above and shown in the figures. For the sake of brevity, detailed descriptions of known methods are omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of this application is not limited to the specific steps described and shown. Those skilled in the art can make various changes, modifications, and additions, or change the order of steps, after understanding the spirit of this application.

[0150] The functional blocks shown in the above-described structural diagram can be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of this application are programs or code segments used to perform the required tasks. Programs or code segments can be stored on a machine-readable medium or transmitted over a transmission medium or communication link via data signals carried on a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable-ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, fiber optic media, radio frequency (RF) links, etc. Code segments can be downloaded via computer networks such as the Internet, intranets, etc.

[0151] It should also be noted that the exemplary embodiments mentioned in this application describe methods or systems based on a series of steps or apparatus. However, this application is not limited to the order of the above steps; that is, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0152] The aspects of this disclosure have been described above with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It should be understood that each block in the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that these instructions, executable via the processor of the computer or other programmable data processing apparatus, enable the implementation of the functions / actions specified in one or more blocks of the flowchart illustrations and / or block diagrams. Such a processor can be, but is not limited to, a general-purpose processor, a special-purpose processor, a special application processor, or a field-programmable logic circuit. It is also understood that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can also be implemented by special-purpose hardware performing the specified functions or actions, or can be implemented by a combination of special-purpose hardware and computer instructions.

[0153] It should also be noted that the exemplary embodiments mentioned in this application describe methods or systems based on a series of steps or apparatus. However, this application is not limited to the order of the above steps; that is, the steps can be performed in the order mentioned in the embodiments, or in a different order, or several steps can be performed simultaneously.

[0154] The above are merely specific embodiments of this application. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific operation processes of the systems, modules, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here. It should be understood that the protection scope of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the protection scope of this application.

Claims

1. A method for controlling resin infusion process, characterized in that, A controller is applied in a resin infusion process control system. The resin infusion process control system further includes an infusion mold, a glue injection device, a vacuum pump, and an image acquisition device. The controller is connected to the glue injection device, the vacuum pump, and the image acquisition device. The infusion mold includes a mold assembly, which includes a molding mold and a fiber preform. The surface of the molding mold is provided with polygonal units distributed in a predetermined spatial pattern. There is a gap between every two adjacent polygonal units, and all gaps are interconnected to form a flow channel. The control method includes: Obtain mold structure parameters, fiber preform permeability, and resin viscosity of the resin to be injected; the mold structure parameters include channel areal density, which is the ratio of the flow channel area to the area of ​​the entire pattern layer on the molding die; the fiber preform permeability includes the first fiber permeability of the polygonal unit region and the second fiber permeability of the flow channel region. During the resin injection process, the air pressure value inside the mold cavity and the image sequence collected during the injection process are obtained. The image acquisition period in the image sequence is determined according to the characteristics of the resin and the injection process parameters. Based on the mold structure parameters, the fiber preform permeability, and the resin viscosity, combined with the air pressure value inside the mold cavity, the theoretical predicted position of the resin flow front is calculated using a dual-zone parallel permeability model; wherein, the dual-zone parallel permeability model is used to describe the parallel flow of resin in the flow channel region and the fiber preform region of the mold cavity. The image sequence is processed to identify the actual position of the resin flow front; The actual location is compared with the theoretically predicted location to obtain the comparison result; Based on the comparison results, the glue injection flow rate of the glue injection device and / or the vacuum degree of the vacuum pump are adjusted in real time. The vacuum degree of the vacuum pump is negatively correlated with the air pressure value in the mold cavity. If the flow front position in the flow channel area is detected to be ahead of the wetting front position in the fiber preform area, and the distance between the flow front position and the wetting front position exceeds a third threshold, the glue injection device is controlled to switch to pulse glue injection mode.

2. The control method according to claim 1, characterized in that, Based on the comparison results, adjust the dispensing flow rate of the dispensing device and / or the vacuum level of the vacuum pump in real time, including: If the actual position lags behind the theoretically predicted position, and the lag distance is greater than or equal to a first threshold, increase the dispensing flow rate of the dispensing device and / or increase the vacuum level of the vacuum pump. If the actual position is ahead of the theoretically predicted position, and the lead distance is greater than or equal to a second threshold, the dispensing flow rate of the dispensing device and / or the vacuum degree of the vacuum pump are reduced.

3. The control method according to claim 2, characterized in that, The control method further includes: When the viscosity of the resin to be injected is less than or equal to the set viscosity threshold, the dual-zone parallel permeability model is corrected by introducing a first inertia correction factor. The theoretically predicted location of the resin flow front was recalculated based on the modified dual-zone parallel permeability model.

4. The control method according to claim 1, characterized in that, The control method further includes: Based on the image sequence, within the identified resin flow front region, the unfilled sub-regions in the fiber preform region are continuously tracked; If the unfilled sub-region is surrounded by a filled flow channel region, and the unfilled sub-region remains unfilled for a duration exceeding a set time threshold, at least one of the following measures shall be performed: Control the dispensing device to switch to pulse dispensing mode; During the resin injection phase of the pulsed dispensing mode, the dispensing flow rate is increased from the current reference flow rate to the set flow rate; Increase the vacuum level of the vacuum pump from the current reference vacuum level to the set vacuum level.

5. The control method according to claim 1, characterized in that, The control method further includes: Each frame of the image sequence is identified to determine the resin filling rate corresponding to each frame of the image. The filling change rate is determined based on the resin filling rate and timestamp information corresponding to each frame of the image. If the resin filling rate corresponding to the current frame image is less than or equal to the fourth threshold, and the filling change rate is greater than or equal to the fifth threshold, reduce the glue injection flow rate of the glue injection device and / or reduce the vacuum degree of the vacuum pump.

6. The control method according to claim 5, characterized in that, The control method further includes: If the resin filling rate corresponding to the current frame image is greater than or equal to the sixth threshold, and the filling change rate is less than or equal to the seventh threshold, the glue injection flow rate of the glue injection device is increased and the vacuum degree of the vacuum pump is decreased, wherein the seventh threshold is less than the fifth threshold.

7. The control method according to claim 5, characterized in that, The control method further includes: If the resin fill rate corresponding to the current frame image is greater than or equal to the eighth threshold, and the fill change rate is less than or equal to the ninth threshold, the image acquisition cycle of the image acquisition device is increased, where the ninth threshold is less than the fifth threshold.

8. A resin infusion process control system, characterized in that, include: A casting mold includes a platform, a mold assembly, and a transparent sealing assembly. The mold assembly is placed on the platform, and the transparent sealing assembly covers the mold assembly, together forming a sealed space. The mold assembly includes a molding die and a fiber preform. The surface of the molding die is provided with polygonal units distributed in a predetermined spatial pattern, with gaps between adjacent polygonal units. All gaps are interconnected to form flow channels. The fiber preform covers the flow channels to form a mold cavity. A resin injection device is connected to the mold cavity through an injection port and configured to inject resin into the mold cavity. A vacuum pump, connected to the mold cavity through a glue outlet, is configured to extract air from the sealed space to create a vacuum. An image acquisition device is disposed on the side of the mold assembly away from the platform and is configured to acquire an image sequence of the resin pouring process in the mold cavity. The image acquisition period in the image sequence is determined according to the characteristics of the resin and the pouring process parameters. The controller, connected to the glue injection device, the vacuum pump, and the image acquisition device, is configured to: acquire mold structure parameters, fiber preform permeability, and resin viscosity; the mold structure parameters include channel areal density, which is the ratio of the flow channel area to the area of ​​the entire pattern layer on the molding die; the fiber preform permeability includes the first fiber permeability of the polygonal unit region and the second fiber permeability of the flow channel region; during resin injection, acquire the air pressure value inside the mold cavity and the image sequence acquired during the injection process; based on the mold structure parameters, fiber preform permeability, and resin viscosity, combined with the air pressure value inside the mold cavity, calculate the resin flow front using a dual-zone parallel permeability model. Theoretical predicted position; wherein, the dual-zone parallel permeability model is used to describe the parallel flow of resin in the flow channel region and the fiber preform region of the mold cavity; the image sequence is processed to identify the actual position of the resin flow front; the actual position is compared with the theoretical predicted position, and based on the comparison result, the injection flow rate of the injection device and / or the vacuum degree of the vacuum pump are adjusted in real time, wherein the vacuum degree of the vacuum pump is negatively correlated with the air pressure value in the mold cavity; when it is identified that the flow front position in the flow channel region is ahead of the wetting front position in the fiber preform region, and the distance between the flow front position and the wetting front position exceeds a third threshold, the injection device is controlled to switch to pulse injection mode.

9. The control system according to claim 8, characterized in that, The outlet is located at the end of the mold cavity, and the distance between the outlet and the mold cavity is greater than a set distance.

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