CN-122008463-A - Resin infusion process control method and control system

Abstract

The application provides a control method and a control system for a resin pouring process, and relates to the technical field of liquid molding. The application accurately describes the parallel flow characteristics of resin in a gully runner and a fiber preform by introducing a double-region parallel permeability model, breaks the prediction deviation caused by neglecting regional difference of a traditional single model, and fundamentally overcomes the blindness and hysteresis of traditional relying experience or fixed program control based on the self-adaptive closed-loop control of model prediction and visual feedback, and realizes fine and active coordination of the resin flow process, thereby effectively preventing internal defects such as dry spots or air bags caused by flow incompatibility, and greatly improving the process success rate and the quality uniformity and reliability of composite material products.

Inventors

• HAN XIN
• LI MENGYU
• XIE GUOXIN
• LUO JIANBIN

Assignees

• 清华大学

Dates

Publication Date

20260512

Application Date

20260409

Claims (11)

1. 1. The resin pouring process control method is characterized by being applied to a controller in a resin pouring process control system, wherein the resin pouring process control system further comprises a pouring mold, a glue injection device, a vacuum pump and an image acquisition device, and the controller is respectively connected with the glue injection device, the vacuum pump and the image acquisition device, and the control method comprises the following steps: obtaining a mold structure parameter, the permeability of a fiber preform and the resin viscosity of resin to be infused; In the resin pouring process, acquiring an air pressure value in a mold cavity and an image sequence acquired in the pouring process, wherein an image acquisition period in the image sequence is determined according to the characteristics of the resin and pouring technological parameters; Calculating a theoretical prediction position of a resin flow front through a double-region parallel permeability model based on the mold structure parameters, the fiber preform permeability and the resin viscosity and in combination with an air pressure value in a mold cavity, wherein the double-region parallel permeability model is used for describing parallel flow of resin in a gully runner region and a fiber preform region of the mold cavity; processing the image sequence, and identifying the actual position of the resin flow front; Comparing the actual position with the theoretical predicted position to obtain a comparison result; And according to the comparison result, adjusting the glue injection flow of the glue injection device and/or the vacuum degree of the vacuum pump in real time, wherein the vacuum degree of the vacuum pump is inversely related to the air pressure value in the die cavity.
2. 2. The control method according to claim 1, wherein adjusting 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 comprises: When the actual position is lagged behind the theoretical prediction position and the lagging distance is larger than or equal to a first threshold value, increasing the glue injection flow of the glue injection device and/or increasing the vacuum degree of the vacuum pump; And under the condition that the actual position is ahead of the theoretical predicted position and the advance distance is greater than or equal to a second threshold value, reducing the glue injection flow of the glue injection device and/or reducing the vacuum degree of the vacuum pump.
3. 3. The control method according to claim 2, characterized in that the control method further comprises: and controlling the glue injection device to switch to a pulse glue injection mode under the condition that the flow front position of the gully runner region is recognized to be ahead of the infiltration front position of the fiber preform region and the distance between the flow front position and the infiltration front position exceeds a third threshold value.
4. 4. A control method according to claim 3, characterized in that the control method further comprises: under the condition that the resin viscosity of the resin to be infused is smaller than or equal to a set viscosity threshold value, the two-region parallel permeability model is corrected by introducing a first inertia correction factor; And recalculating the theoretical prediction position of the resin flow front based on the modified double-zone parallel permeability model.
5. 5. The control method according to claim 1, characterized in that the control method further comprises: continuously tracking the unfilled subregions in the fiber preform region within the identified resin flow front region according to the image sequence; In the case where the unfilled subregion is surrounded by a filled gully runner region and the duration of the unfilled subregion remaining unfilled exceeds a set time threshold, at least one of the following measures is carried out: Controlling the glue injection device to switch to a pulse glue injection mode; in the resin injection stage of the pulse type glue injection mode, increasing the glue injection flow from the current reference flow to the set flow; And increasing the vacuum degree of the vacuum pump from the current reference vacuum degree to a set vacuum degree.
6. 6. The control method according to claim 1, characterized in that the control method further comprises: identifying each frame of image in the image sequence, and determining the resin filling rate corresponding to each frame of image; Determining a filling change rate according to the resin filling rate and the time stamp information corresponding to the images of each frame; And when the filling rate of the resin corresponding to the current frame image is smaller than or equal to a fourth threshold value and the filling change rate is larger than or equal to a fifth threshold value, reducing the glue injection flow of the glue injection device and/or reducing the vacuum degree of the vacuum pump.
7. 7. The control method according to claim 6, characterized in that the control method further comprises: And when the filling rate of the resin corresponding to the current frame image is larger than or equal to a sixth threshold value, and the filling change rate is smaller than or equal to a seventh threshold value, increasing the glue injection flow of the glue injection device and reducing the vacuum degree of the vacuum pump, wherein the seventh threshold value is smaller than the fifth threshold value.
8. 8. The control method according to claim 6, characterized in that the control method further comprises: And when the filling rate of the resin corresponding to the current frame image is larger than or equal to an eighth threshold value and the filling change rate is smaller than or equal to a ninth threshold value, increasing the image acquisition period of the image acquisition device, wherein the ninth threshold value is smaller than the fifth threshold value.
9. 9. A resin infusion process control system, comprising: The pouring mold comprises a storage table, a mold assembly and a transparent sealing assembly, wherein the mold assembly is arranged on the storage table, the transparent sealing assembly covers the mold assembly and forms a sealing space together with the mold assembly, the mold assembly comprises a molding mold and a fiber preform, the surface of the molding mold is provided with a preset micro-channel structure, and the fiber preform covers the micro-channel structure to form a mold cavity; The glue injection device is communicated with the mold cavity through a glue injection port and is configured to inject resin into the mold cavity; The vacuum pump is communicated with the mold cavity through the glue outlet and is configured to pump air in the sealed space to form vacuum; The image acquisition device is arranged on one side, far away from the object placing table, of the die assembly and is configured to acquire an image sequence of the resin in the pouring process in the die cavity, and the image acquisition period in the image sequence is determined according to the characteristics of the resin and the pouring process parameters; The controller is respectively connected with the glue injection device, the vacuum pump and the image acquisition device and is configured to acquire a mold structure parameter, the permeability of a fiber preform and the viscosity of resin, acquire an air pressure value in a mold cavity and an image sequence acquired in the pouring process in the resin pouring process, calculate a theoretical prediction position of a resin flow front through a double-area parallel permeability model based on the mold structure parameter, the permeability of the fiber preform and the viscosity of the resin and the air pressure value in the mold cavity, wherein the double-area parallel permeability model is used for describing parallel flow of the resin in a gully runner area and a fiber preform area of the mold cavity, process the image sequence, identify an actual position of the resin flow front, compare the actual position with the theoretical prediction position, and adjust the glue injection flow of the glue injection device and/or the vacuum degree of the vacuum pump in real time according to a comparison result, and the vacuum degree of the vacuum pump is inversely related to the air pressure value in the mold cavity.
10. 10. The control system of claim 9, wherein the glue outlet is disposed at a distal end of the mold cavity and a distance from the mold cavity is greater than a set distance.
11. 11. The control system of claim 9, wherein the microchannel structure comprises a polygonal micro-groove structure.

Description

Resin infusion process control method and control system Technical Field The application belongs to the technical field of liquid molding, and particularly relates to a control method and a control system for a resin pouring process. Background The vacuum assisted resin infusion process is a critical process for manufacturing large composite components. In this process, the resin fills the mold cavity of the fiber-rich preform under pressure differential drive. To facilitate resin flow, the mold surface is often pre-set with runners. However, the flow front morphology of the resin becomes complex and difficult to predict when it simultaneously flows through different regions where the difference in permeability is significant. In the related art, the control method is mostly dependent on empirical observation of an operator or a simple preset program based on an idealized uniform flow assumption. The method can not accurately sense and respond to the dynamic change of the actual flowing state in real time, so that the resin flows in the mould in an uncoordinated way, the defects of local non-infiltration, dry spots or closed air bags and the like are easily generated, the quality stability and the yield of products are seriously affected, and the problem is more remarkable especially for complex structural parts. Therefore, there is an urgent need in the industry for a resin infusion control method that can more accurately describe flow behavior and achieve intelligent closed-loop regulation. Disclosure of Invention The embodiment of the application provides a control method and a control system for a resin pouring process, which are based on self-adaptive closed-loop control of model prediction and visual feedback, and realize fine and active coordination of a resin flowing process, thereby effectively preventing internal defects such as dry spots or air bags and the like caused by uncooled flowing, and greatly improving the process success rate and the quality uniformity and reliability of composite material products. In a first aspect, an embodiment of the present application provides a method for controlling a resin infusion process, which is applied to a controller in a resin infusion process control system, where the resin infusion process control system further includes an infusion mold, an adhesive injection device, a vacuum pump, and an image acquisition device, and the controller is respectively connected with the adhesive injection device, the vacuum pump, and the image acquisition device, and the method includes: obtaining a mold structure parameter, the permeability of a fiber preform and the resin viscosity of resin to be infused; in the resin pouring process, acquiring an air pressure value in a mold cavity and an image sequence acquired in the pouring process, wherein an image acquisition period in the image sequence is determined according to the characteristics of the resin and pouring technological parameters; Calculating a theoretical prediction position of a resin flow front through a double-region parallel permeability model based on a mold structural parameter, the permeability of a fiber preform and the viscosity of the resin and combining an air pressure value in a mold cavity, wherein the double-region parallel permeability model is used for describing parallel flow of the resin in a gully runner region of the mold cavity and a fiber preform region; processing the image sequence, and identifying the actual position of the resin flow front; comparing the actual position with the theoretical predicted position to obtain a comparison result; and according to the comparison result, the glue injection flow of the glue injection device and/or the vacuum degree of the vacuum pump are/is adjusted in real time, and the vacuum degree of the vacuum pump is inversely related to the air pressure value in the die cavity. In some embodiments, adjusting 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 includes: When the actual position is lagged behind the theoretical predicted position and the lagging distance is larger than or equal to a first threshold value, increasing the glue injection flow of the glue injection device and/or increasing the vacuum degree of the vacuum pump; And under the condition that the actual position is advanced from the theoretical predicted position and the advanced distance is greater than or equal to a second threshold value, reducing the glue injection flow rate of the glue injection device and/or reducing the vacuum degree of the vacuum pump. In some embodiments, the control method further comprises: and controlling the glue injection device to switch to a pulse glue injection mode under the condition that the flow front position of the gully runner region is recognized to be ahead of the infiltration front position of the fiber preform region and the distance betw