Automatic removal processing method and system for damage repair area of continuous fiber composite material

Abstract

The invention discloses an automatic removal processing method and system for a damage repair area of a continuous fiber composite material, and belongs to the field of repair and remanufacturing of continuous fiber composite materials. The method comprises the following steps: firstly, fixing a workpiece, discretizing a damaged area and planning a cutter path; and the system sequentially removes a surface paint layer and a fiber layer, specifically, the paint layer is machined firstly, and then layered cutting is conducted by visually detecting the fiber direction. And after each layer of fiber is removed, comparing the direction through a camera, if the direction is not changed, continuing to process the current layer, otherwise, switching the path until all the fibers are removed. And finally recording parameters and ending the process. According to the method, accurate layering machining is achieved based on visual feedback, universality is high, the method can be suitable for automatic removal of free-form surface composite materials and metal structures through configuration adjustment, and the method has good application prospects in the field of aviation outfield repair.

Description

Technical Field

[0001] This invention belongs to the field of continuous fiber composite material repair and remanufacturing, and particularly relates to an automatic removal processing method and system for damaged repair areas of continuous fiber composite materials. Background Technology

[0002] In the aerospace field, carbon fiber composites are key to achieving lightweight aircraft. The application of this material significantly reduces aircraft weight, effectively lowering fuel consumption and operating costs, while also improving structural strength and lifespan, and enhancing flight safety and comfort.

[0003] However, carbon fiber composites also present certain challenges in aerospace applications. Aircraft, especially military aircraft, face harsh flight environments, making them susceptible to impacts from external objects during high-speed flight and takeoff and landing. Furthermore, mechanical loads and environmental factors can damage the composite structure of aircraft during use. Since carbon fiber resin composites are composed of carbon fibers and a resin matrix, forming a laminated structure, when subjected to impacts or scratches, only minor surface marks (such as dents or resin cracks) may appear, but internal damage such as delamination and fiber breakage may have already occurred. If this damage is not addressed promptly, it will gradually expand under subsequent loads, leading to a significant decrease in overall strength. For example, an unrepaired impact damage of 5mm in diameter may reduce the material stiffness by more than 30% under cyclic loading. Carbon fibers bear the majority of the load in CFRP structures (approximately 90% or more). Once fibers break or delamination occurs, the damaged area cannot effectively transfer stress, leading to load concentration in adjacent areas. For example, if minor delaminations in the skin of an aircraft wing are not repaired, repeated aerodynamic loads during flight may cause cracks to propagate along the fiber direction, ultimately affecting the overall load-bearing capacity of the wing and even leading to structural failure.

[0004] Unlike welding or riveting repairs of metal components, current methods for repairing damaged areas of carbon fiber composites primarily involve adhesive patching. These methods can ideally restore structural strength to over 85% of its original performance. The adhesive patching process requires grinding and removing material from the damaged area according to specific design rules. Common repair structures include circular stepped structures, continuous conical structures, and irregular square repair structures. This design effectively reduces stress concentration, and the thickness is arranged in a stepped manner. Transition (thickness difference per step ≤ 0.5mm, and the fiber design direction of the patch should preferably be consistent with the thickness of the fiber at the layup angle of each layer), before gluing the patch, the following steps need to be completed: (1) Visually inspect and professionally ultrasonically test the damaged defect area to determine the damaged defect area, (2) Grind and remove the material of the damaged defect area according to the design requirements of the repair process. At present, the removal of the material of the design shape of the continuous fiber damage defect area of ​​aircraft relies on manual operation with professional skills. The fiber damage grinding operator needs to have both "technical precision" and "safety awareness". He must master the material characteristics and process details (such as gradient grinding and surface treatment) through professional training, and strictly implement safety protection and environmental protection regulations to ensure that the repair operation meets the structural performance requirements and protects the health and safety of personnel. Therefore, it is urgent to invent a processing method and system for automatic removal of fiber damage structural areas, which can not only get rid of the problems of low precision, low efficiency and dependence on professional skills personnel in the manual grinding of aircraft equipment damage defect areas, but also avoid the harm of fiber dust generated by grinding to the health of operators. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an automatic removal processing method and system for the damaged repair area of ​​continuous fiber composite materials. This solves the problems of low precision and low efficiency of manual grinding of damaged defect areas of aircraft and aviation equipment, as well as the dependence on skilled personnel, and the problem that the fiber dust generated by grinding and removal is harmful to the health of operators.

[0006] To achieve the above objectives, the present invention employs the following technical solution: An automated removal process for damaged areas in continuous fiber composite materials includes the following steps: S1, the composite material structural part to be processed is installed below the multi-degree-of-freedom motion system through the vacuum suction cup assembly. The composite material structural part has a damaged or defective area. The multi-degree-of-freedom motion system is equipped with a high-speed cutting tool and a camera. S2, the damaged defect area of ​​the composite material structure is decomposed into multiple discrete points, and the coordinates of each discrete point are obtained; the multi-degree-of-freedom motion system sets the distance between the high-speed cutting tool and the damaged defect area as a reserved installation distance; based on the coordinates of each discrete point, the high-speed cutting tool moves along the maximum envelope size of the pre-set CAM path; S3, calculate the coordinates of each discrete point in the damaged defect area after removing the paint layer thickness; S4: Collect the height parameters of each discrete point in the damaged defect area, and combine them with the paint layer thickness to obtain the coordinates of the processing data points of each discrete point in the damaged defect area after removing the paint layer thickness. S5, the multi-degree-of-freedom motion system drives the high-speed cutting tool to process the surface paint layer of the damaged defect area in a linear interpolation manner according to the coordinates of the processing data points, and remove the surface paint layer. S6, the camera takes pictures of the damaged area to obtain the fiber layer laying direction; based on the processing data point coordinates of each discrete point obtained in S4, combined with the thickness of the fiber layer, the fiber cutting data coordinate points are obtained. S7, the high-speed cutting tool processes the fiber layer in the damaged defect area according to the fiber cutting data coordinate points; S8: Take pictures of the damaged defect area where the surface fiber layer has not been removed by a camera to obtain the fiber layer laying direction. Compare the fiber layer laying direction with the original fiber layer laying direction obtained in S6. If they are consistent, repeat S7 until the fiber layer in the same direction is removed. Otherwise, proceed to S9. S9, the computer control system retrieves the CAM code for the processing path in the direction of the next fiber layer, and repeats S6-S8 to complete the processing of the next fiber layer; S10, repeat S9 until all fiber layers in the damaged defect area are removed; S11: Take a picture of the damaged area using a camera to obtain a complete image of the patch parameters for the damaged processing area and store it, thus ending the processing.

[0007] A further improvement of the present invention is that: Preferably, in S2, the path of the processing pattern of the damaged defect area is composed of line segments, and the coordinates of each discrete point are obtained after discretizing the line segments.

[0008] Preferably, in S2, the multi-degree-of-freedom motion system moves the high-speed cutting tool to the highest point of the damaged defect area, and uses the coordinates of the highest point after removing the paint layer thickness as the machining start point.

[0009] Preferably, during the surface coating process, S5 processes the coating along a path from the maximum envelope size to the minimum envelope size.

[0010] Preferably, in step S6, during the process of obtaining the fiber layer laying direction, half of the processed images are fitted to obtain the fiber layer laying direction.

[0011] Preferably, in S6, the formula for calculating the fiber cutting coordinate points is: , in, , and These are the coordinates of the discrete points being measured. The thickness of a single fiber layup. Paint layer thickness, The Z-axis height of the data point relative to the fiber surface is typically 0.2mm-0.4mm thick.

[0012] Preferably, during process S7, the processing path for the fiber layer in the damaged defect area is a path that gradually decreases from the maximum external dimension or gradually increases from the minimum dimension.

[0013] Preferably, dust is collected by negative pressure during the S2-S9 process.

[0014] Preferably, during the process of S2-S9, the width of each machining operation is the width of the high-speed cutting tool (13).

[0015] An automatic removal device for damaged areas of continuous fiber composite materials used to implement the above-mentioned processing method includes a multi-degree-of-freedom motion system, which is mounted on the composite material structure via a vacuum suction cup assembly; a high-speed rotating spindle is connected to the lower end of the multi-degree-of-freedom motion system, and a negative pressure collection hood and a high-speed cutting tool are installed at the front end of the high-speed rotating spindle, with the high-speed cutting tool housed within the negative pressure collection hood; a camera, an ultrasonic thickness gauge, and a laser rangefinder are mounted on the high-speed rotating spindle; the negative pressure collection hood is connected to a dust collector via a dust collection pipeline. The multi-degree-of-freedom motion system, vacuum suction cup assembly, and dust collector are all electrically connected to the computer control system.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention discloses an automated removal processing method for damaged areas of continuous fiber composite materials. It performs real-time online detection and calculation of the Z-axis coordinate of the part to be processed, achieving real-time online height compensation of the high-speed cutting grinding head. This eliminates the need for automated manufacturing methods that rely on 3D scanning, digital modeling, and cutting path planning of composite parts, reducing the engineering and technical difficulty of repairing and remanufacturing fiber composite parts with curved shapes. An intelligent camera system is used to photograph and calculate the fiber direction of the grinding layer, analyzing the fiber direction of each grinding removal layer in real time to avoid overcutting. Simultaneously, the overall removal shape after processing is photographed and combined into a model, calculating the size of the removed material and the fiber path direction of each direction layer, providing reliable data input for subsequent patch fabrication. This invention enables the automated removal of damaged and defective fiber composite structures using an automated removal processing system. On one hand, it can achieve high-precision automated removal of damaged and defective areas according to pre-set patch shape requirements, eliminating reliance on manual expertise. On the other hand, the automated dust collection system prevents manual damage to human health from fiber powder during high-speed grinding, which is particularly important in in-situ repair environments lacking necessary protective measures. This method has high versatility and scalability, and can be applied to automated removal processing systems for damaged and defective patches in various fiber composite structures. With appropriate configuration and adjustment of the distance acquisition device, intelligent camera system, and control system, it can not only automate the removal of damaged and defective areas in free-form fiber composite parts but also automate the removal of damaged and defective areas in free-form metal structural components. It has broad application prospects and market value in the field of aerospace structural repair and remanufacturing.

[0017] This invention provides an automatic removal system for continuous fiber damage repair areas, which mainly consists of a computing and control system, a vacuum adsorption system, a multi-degree-of-freedom motion system, a high-speed rotating spindle, a cutting tool, an intelligent camera, a Z-axis height laser rangefinder, an ultrasonic detector, and a negative pressure dust collection system. The computer control system is used for the operation of the entire system and the processing of corresponding algorithms. The vacuum adsorption system can fix the entire machining system on the surface of the workpiece through a vacuum suction cup. The multi-degree-of-freedom motion system is used to drive the high-speed rotating spindle and cutting tool to move and process according to the calculated and designed path. The ultrasonic detector can detect the thickness of the paint layer sprayed on the surface of the fiber composite structure through specific ultrasonic signals. The host computer automatically obtains the fiber lay-up path direction on the surface of the area to be processed through the fiber lay-up direction calculation method of the high-precision intelligent camera, thereby accurately controlling the thickness and size of the removed layer in different fiber lay-up directions. The height parameter of the cutting tool from the surface to be cut is obtained through the Z-axis height laser rangefinder. Through the discrete point-to-point data control algorithm, the height difference compensation calculation can be performed on the preset CAM machining code inside the control system to accurately adjust the Z-axis height parameter of the machining tool and achieve precise cutting control of the layer height in a specific fiber direction. This eliminates the need for three-dimensional digital modeling of parts and professional CAM path planning required by this cutting technology, thereby improving the applicability of the automated removal machining system to the repair and remanufacturing of unknown curved surface fiber composite structures and reducing the professional skills required of operators. Through the synergistic effect of the above systems and the corresponding computer control methods, the processing shape accuracy, fiber layup direction accuracy, and processing height direction precision of the automatic removal process are improved during the removal of damaged and defective areas of composite materials, thus meeting the field in-situ repair needs in the field of repair and remanufacturing of fiber composite aerospace structural components. Attached Figure Description

[0018] Figure 1 This is a diagram illustrating the components of an automatic removal system for damaged areas in continuous fiber composites according to this application. Figure 2 This is a structural composition diagram of a typical fiber composite material according to this application; Figure 3 This is a cross-sectional view showing the removal of a damaged structure according to this application; Figure 4 Flowchart for removing conical step damage in this application with different fiber directions; Figure 5 This is a flowchart illustrating the removal process for rectangular step-shaped damage in this application, showing the removal of fibers in different directions.

[0019] 1. Computer control system; 2. Vacuum suction cup assembly; 3. Multi-degree-of-freedom motion system; 4. High-speed rotary spindle; 5. Negative pressure collection hood; 6. Camera; 7. Laser rangefinder; 8-1. Dust collector; 8-2. Dust collection pipeline; 9. Ultrasonic thickness gauge; 10. Damaged / defective area; 11. Composite material structural component; 12. Mounting bracket; 13. High-speed cutting tool; 14. Free curvature surface; 15. Cartesian coordinate system; 16. Ply angle of composite structure ; 17. Cross-sectional view of the composite structure after removing the damaged and defective area; 18. Fiber 0° cut layer; 19. Fiber 45° cut layer; 20. Fiber 90° cut layer; 21. Fiber 45° cut layer; 22. Fiber 0° cut layer; 23. Parameter diagram of patch in the damaged and defective area. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings: Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0021] This invention discloses an automatic removal processing method for damaged areas of fiber composite materials. The material removal of the damaged and defective areas of the fiber composite material structure is achieved by a high-speed rotating spindle driving a cutting tool to grind and cut the fiber layer at high speed. The cutting tool can be a grinding tool or a milling tool. Any tool that can perform high-speed fiber cutting can be used. This invention does not limit the type of cutting tool.

[0022] The invention is characterized in that the control system issues specific instructions to use vacuum chucks to fix the automatic removal processing system to the damaged defect area of ​​the composite structure workpiece to be repaired, wherein the number of vacuum chucks is [number missing]. The specific quantity is not limited in this invention.

[0023] This invention relates to an automated removal process for continuous fiber damage repair areas. The specific processing control method includes the following steps: Step 1: The automated fiber damage defect area removal processing system has completed all preparations. The processing and cutting system uses a vacuum suction cup assembly to vacuum-adsorb and fix the fiber damage defect area onto the surface of the area to be processed and removed. Step two: A negative pressure collection shroud 5 is arranged around the high-speed rotating spindle 4 on which the high-speed cutting tool 13 is mounted. It is connected to an external negative pressure and dust collection system through a flexible pipe. Sufficient installation distance is reserved for the high-speed cutting tool 13 in the area to be machined, which has a free curvature surface 14. Then, the tool moves along the pre-set CAM path with the maximum envelope size. In this invention, the envelope size refers to the overall outline boundary of the damaged area to be machined, specifically the maximum outer dimension of the damaged area, which is usually used to describe the maximum range of motion of the tool during machining or the machining start boundary.

[0024] The spindle, equipped with a high-speed cutting tool at its front end, is fixedly mounted on the Z-axis of this multi-degree-of-freedom motion system (3 degrees of freedom or more). The Z-axis is sequentially connected to other linear motion axes, forming a Cartesian coordinate system motion mode. The multi-degree-of-freedom motion system can be used for Cartesian coordinate robots, such as gantry cranes, three-axis or four-axis motion platforms.

[0025] The path trajectory of the cutting tool is mainly composed of It consists of a motion system with 1 degree of freedom, in which It can drive the cutting tool to achieve continuous interpolation motion of the tool in multiple degrees of freedom in space, thereby realizing the interpolation and removal of two-dimensional path damage structures with equal height, such as stepped circles and stepped rectangles, in the continuous fiber composite structure repair area. All processed areas are cut and removed using linear interpolation. The component paths of the damaged defect area 10 are discretized into tiny line segments, and then the points obtained from the data discretization are... Then the data coordinates can be represented by Cartesian coordinates: , The material removal width is the width diameter d of the tool, and tool compensation is performed on the cutting data coordinates.

[0026] Step 3: The ultrasonic thickness gauge 9 is fixedly installed on the side of the high-speed rotating spindle 4. According to relevant instructions, the thickness of the protective paint sprayed on the fiber composite structure plane is measured to obtain the paint layer thickness. The data is recorded inside the computer control system 1. The multi-degree-of-freedom motion system 3 moves the high-speed cutting tool 13 to the highest point of the damaged defect area, and records the coordinates of the highest point of the surface to be removed as the initial machining coordinates, which are also recorded inside the control system. This highest point A1 is used as the (…). Processing start point.

[0027] Initial machining coordinates of the defect area to be damaged: The calculation yields:

[0028] The laser rangefinder can continuously scan the Z-axis height data of the cutting path according to the requirements of the control system, wherein the sampling points of the sampling path are... The control system discretizes the Z-axis height measurement data to obtain the following data: It also performs real-time calculation of the Z-axis coordinates of the path point.

[0029] Step 4: Since Z0 is the highest point of the region to be removed, it is also stipulated that: The positive direction of the Z-axis is away from the workpiece surface; therefore, the real-time calculation formula for the height direction is:

[0030] The number of coordinates for the linear interpolation motion to remove the sprayed paint layer was calculated to be: The Z-axis coordinate of the first layer removal direction is:

[0031] in, To measure the thickness of the paint layer, the coordinates of each discrete point of the cutting tool during the material machining process are: .

[0032] The computing system obtains After the data points are collected, they are stored in the computer control system, and then the drive system drives the laser rangefinder 7 pairs. The Z-axis height data of the data points are measured to obtain the height parameter of the laser rangefinder relative to each sampling point. The computer control system calculated the coordinates of the processing data points for removing the composite paint layer at the same height on the freeform surface as follows:

[0033] Step 5: The computer control system 1 activates the dust collection negative pressure system, and simultaneously drives the multi-degree-of-freedom motion system 3 to move the cutting spindle according to... The surface paint layer is processed by linear interpolation of coordinate points to remove the paint layer. After the first tool width d path point is processed, steps one to four are repeated to process and remove the paint layer from the outside to the inside, that is, from the maximum envelope size to the minimum envelope size, to complete the processing of the entire paint layer surface. During this process, data sampling is performed once for each processing.

[0034] Step Six: After the protective paint layer is applied to the damaged and defective areas of the fiber composite structure, the drive system drives the intelligent camera 6 to take pictures and calculate the fiber direction of the removed surface. The coordinates of the picture points are: Number of photos taken In order to reduce the storage size and processing speed of the photos, the host computer control system originally processed the following number of photos internally, based on the photo processing method: , where n is an even number sequence, the laying direction angle θ1 of the fiber layer is obtained by fitting the photograph and recorded inside the control system.

[0035] Specifically, when calculating the fiber orientation using the photograph obtained by the camera 6, the image processing unit performs grayscale and edge enhancement processing on the acquired photograph. Then, the Hough transform algorithm is used to detect the main direction of the linear features in the image, and the main direction is determined as the laying direction of the current fiber layer.

[0036] During this process, the paint layer sprayed on top of the composite material structure within the damaged area is removed from the outside to the inside according to a predetermined CAM program. A multi-degree-of-freedom motion system drives the intelligent camera to perform the removal according to a pre-set... Take photos based on data coordinates, the number of photos taken To reduce the storage size of photos and the complexity of the computing system, the host computer control system only needs to process the following number of photos internally: By fitting photos along the entire cutting path, the fiber layer's laying direction θi (θi=0°, 45°, 90°, -45° and 0°) is obtained. Step seven, simultaneously drive the laser rangefinder to... The height parameter is obtained by measuring the Z-axis height of the data point relative to the fiber surface. Calculate the coordinate points of fiber cutting data The calculation formula is:

[0037] in - The thickness of a single fiber layup is generally 0.2mm-0.4mm. In the above formula, the thickness of the single fiber layup is divided by 3 to make the thickness of the fiber layer more uniform.

[0038] Step 8: The computer control system activates the negative pressure system and simultaneously drives the multi-degree-of-freedom motion system to move the cutting spindle according to... The fiber layer is processed at the coordinate points. After the first tool width path point is processed, repeat steps S6 and S7 to process from the inside out, that is, from the maximum envelope size to the minimum envelope size, to complete the removal of the fiber layer. Step Nine: The drive system drives the intelligent imaging system to take pictures and calculate the fiber direction of the unremoved surface, obtain the fiber direction θ2 feature of the surface, and compare it with the original stored fiber layer direction θ1. If the direction of the unprocessed fiber layer surface is consistent with the fiber layer direction recorded in the control system, then continue to execute steps six to eight to complete the removal of fiber layer material in the same direction.

[0039] During this process, the fiber paths of the damaged defect areas in a specific fiber direction are all gradually reduced from the maximum external size or gradually expanded from the minimum size to the maximum size until all fibers in this fiber direction are removed. This invention does not limit this path. After each removal of damaged material within the full-size thickness plane, the fiber direction of the unremoved surface needs to be photographed and calculated to obtain the fiber direction characteristics of the surface. When the calculated fiber direction is inconsistent with the fiber direction of the previous layer, the computer control system retrieves the CAM code for the removal path of damaged material in the next fiber thickness direction layer and removes the fiber material in the next direction layer.

[0040] Step 10: When the fiber layer direction calculated by the drive system and the intelligent imaging system is inconsistent with the previous layer, the computer control system retrieves the CAM code for the processing path of the next fiber layer direction, with coordinates as follows: Repeat steps six through nine to complete the material removal process in the thickness direction of the fiber layer; Step 11: Continue to cycle through Steps 6-10 until the fiber material in the damaged area has been processed according to the CAM code required for patching the damaged area. At the same time, the computer control system shuts down the negative pressure dust collection system. Step 12: After executing the CAM code for processing and removing damaged material from all defective areas, the drive system drives the intelligent camera according to the relevant... The coordinate path is used to take pictures, and then the pictures of the processing area are fitted and processed to obtain the complete shape of the damaged processing area patch. The fiber layup direction θ of each processing thickness is recorded and organized to form a complete patch parameter image of the damaged defect area, which is recorded inside the computer control system.

[0041] S13, the computer control system turns on the vacuum adsorption system. After the vacuum suction cup is released, the automated removal system is removed from the surface of the composite structure and placed in the designated position.

[0042] In the above process, after the complete removal of damaged material from all damaged and defective areas, the drive system drives the intelligent camera to take pictures along the relevant path. Then, the pictures of the processed area are fitted and processed to obtain the complete shape of the damaged processed area patch. The fiber direction of each processing step is recorded and organized to form a complete parameter image of the damaged and defective area patch.

[0043] In some embodiments of the present invention, the thickness removed per layer (h3) for a specific laying direction of the fiber layer is less than the thickness of a single layer of fiber prepreg (h4), wherein the calculation formula is: Meanwhile, the Z-axis coordinates removed for each layer of fiber layer thickness need to be compensated for by using a laser rangefinder to compensate for the height of different curved surface coordinate points along the path, so as to achieve material removal at the same height along the cutting path.

[0044] In some embodiments of the present invention, a vacuum negative pressure system is arranged around the spindle cutting tool during the automated machining process of damage removal. When the material removal process begins, the vacuum negative pressure system is activated to collect the generated fiber powder into a designated collector through negative pressure, preventing the fiber powder from freely drifting and causing occupational hazards to the human body.

[0045] The second aspect of the present invention discloses an apparatus for implementing the above-described processing method, the apparatus comprising a computer control system 1, a vacuum suction cup assembly 2, a multi-degree-of-freedom motion system 3, a high-speed rotating spindle 4, a negative pressure collection hood 5, a camera 6, a laser rangefinder 7, a dust collector 8-1, a dust collection pipeline 8-2, and an ultrasonic thickness gauge 9.

[0046] The multi-degree-of-freedom motion system 3 is mounted on the composite material structure 11 via a vacuum suction cup assembly 2; a high-speed rotating spindle 4 is connected to the lower end of the multi-degree-of-freedom motion system 3, and a negative pressure collection hood 5 and a high-speed cutting tool 13 are installed at the front end of the high-speed rotating spindle 4, with the high-speed cutting tool 13 housed within the negative pressure collection hood 5; a camera 6, an ultrasonic thickness gauge 9, and a laser rangefinder 7 are mounted on the high-speed rotating spindle 4; the negative pressure collection hood 5 is connected to a dust collector 8-1 via a dust collection pipe 8-2; The multi-degree-of-freedom motion system 3, the vacuum suction cup assembly 2, and the dust collector 8-1 are all electrically connected to the computer and the computer control system 1.

[0047] The method of the present invention will be described in detail below with reference to specific embodiments: Example 1 The following is a detailed explanation of the removal process for a stepped cone-shaped damaged body with a maximum diameter of φ300mm and a minimum diameter of 100mm, using a composite material layup structure consisting of 5 layers of fibers as an example. An automated removal process and system for damaged areas in continuous fiber composite materials includes the following steps: S1: The preparation work of the automated fiber damage defect area removal processing system is completed. The three-degree-of-freedom motion mechanism 3 of the processing and cutting system is vacuum adsorbed and fixed on the curved surface 14 of the area to be processed and removed by the vacuum suction cup assembly 2. The high-speed rotating spindle 4, with a high-speed cutting tool 13 mounted at the front end, is fixedly mounted on the Z-axis of the multi-degree-of-freedom motion system 3. The Z-axis is connected in series with other linear motion axes to form a Cartesian coordinate system 15 motion mode.

[0048] S2: A negative pressure collection hood 5 is arranged around the high-speed rotary cutting tool 13, which is connected to the external negative pressure and dust collector 8-1 through the dust collection pipe 8-2. The high-speed cutting tool 13 has sufficient installation distance reserved in the machining area with free-form surface-15. Then, its high-speed rotating tool 13 moves along the pre-set CAM path and the maximum envelope size of φ300mm diameter, and records the coordinates of the highest point of the surface to be removed as the initial machining coordinates and records them inside the computer control system 1, and uses A1 as ( Processing starting point; S3: The thickness of the protective paint sprayed on the fiber composite structure plane is measured by the ultrasonic thickness gauge 9 mounted on the side of the high-speed rotating spindle 4 using the mounting bracket 12. The thickness of the paint layer is found to be 2mm. The initial processing coordinates of the defect area to be damaged are as follows: The calculation yields:

[0049] S4: Computer control system 1 obtains After the data points are collected, they are stored in the computer control system 1, and then the laser rangefinder 7, which is mounted on the side of the high-speed rotating spindle 4 via the mounting bracket 12, is driven. The height parameter is obtained by measuring the Z-axis height data of the data points. The computer control system 1 calculates the coordinates of the processing data points for removing the composite paint layer at height 15 on the freeform surface as follows:

[0050] S5: The computer control system 1 opens the dust collector 8-1, and simultaneously drives the multi-degree-of-freedom motion system 3 to drive the high-speed cutting tool 13 according to... The surface paint layer is machined using linear interpolation at the coordinate points, with a tool width d = 6 mm.

[0051] S6: Repeat S1 to S5 to process and remove the φ300mm diameter circular paint layer from the outside to the inside. The circumference diameter formed by linear interpolation is reduced by 12mm. Therefore, S1 to S4 needs to be repeated 25 times to complete the processing of the entire paint layer with a thickness of 2mm.

[0052] S7: After the protective paint layer thickness of 2mm is completed on the surface of the damaged area of ​​the fiber composite structure, it is fixed to the side of the high-speed rotating spindle 4 by the mounting bracket 12. The computer control system 1 drives the multi-degree-of-freedom motion system 3 to drive the camera 6 to take pictures and calculate the direction of the surface fibers that have not been removed. The coordinates of the picture point are: Number of photos taken In order to reduce the storage size and processing speed of photos, the host computer control system extracts the following number of photos from the original internal processing method: By fitting the photograph, the laying direction angle θ1=0° of the fiber layer is obtained, which is the 0° fiber cutting layer 18; S8: Simultaneously drives 7 pairs of laser rangefinders via the drive system. The height parameter is obtained by measuring the Z-axis height of the data point relative to the surface 14 of the curvature fiber. Calculate the coordinate points of fiber cutting data The calculation formula is: , in - Single-layer fiber layup thickness 0.3mm.

[0053] S9: The computer control system 1 opens the negative pressure collector 8-1, and simultaneously drives the multi-degree-of-freedom motion system 3 to drive the high-speed cutting tool 13 according to... The fiber layer is processed at the coordinate points. After the path points are processed with a tool width of 6mm, the diameter of the cutting circle in the 0° direction of the fiber is φ300mm.

[0054] S10: Repeat S7-S9 from the outside to the inside to complete the processing and removal of the φ300mm diameter θ1=0° fiber layer. The circumferential diameter formed by linear interpolation is reduced by 12mm. Therefore, S7 to S9 need to be repeated 25 times to complete the processing of the entire fiber layer with a thickness of 0.1mm.

[0055] S11: The computer control system 1 drives the camera 6 to take pictures and calculate the direction of the unremoved surface fibers, and compares the direction with the original stored fiber layer direction θ1=0°. If the direction of the unprocessed fiber layer surface is consistent with the fiber layer direction recorded in the control system, then continue to execute S7-S10 to complete the removal of the fiber layer material in the same direction θ1=0°. The circumference of the fiber direction with a diameter φ=300mm and a thickness of 0.2mm is processed.

[0056] S12: The computer control system 1 drives the camera 6 to take pictures and calculate the direction of the unremoved surface fibers, obtaining the fiber direction θ2=-45° fiber 45° cutting layer 19 feature. The computer control system 1 retrieves the CAM code for the next fiber layer direction, with coordinates as follows: Complete the removal of material with a diameter of φ260mm, a thickness of 0.1mm, and a width of 6mm.

[0057] S13: Repeat S7-S9 from the outside to the inside to complete the processing and removal of the φ260mm diameter θ2=-45° fiber 45° cutting layer. The circumferential diameter of the linear interpolation is reduced by 12mm. Therefore, S7 to S9 need to be repeated 22 times to complete the processing of the entire fiber layer with a thickness of 0.1mm.

[0058] S14: The computer control system 1 drives the camera 6 to take pictures and calculate the direction of the unremoved surface fibers, and compares the direction with the original stored fiber layer direction θ2=-45°. If the direction of the unprocessed fiber layer surface is consistent with the fiber layer direction recorded in the control system, then continue to execute S7-S9 to complete the removal of the fiber layer material in the same direction θ2=-45°, with a diameter φ=260mm and a thickness of 0.4mm.

[0059] S15: When the fiber layer direction calculated by the computer control system 1 and the camera system 6 is inconsistent with the previous layer, it is determined that the fiber layup direction θ3=90° and the fiber 90° cutting layer 20 is cut. The computer control system 1 retrieves the processing path CAM code for the next fiber layer direction, repeats S7-S9, and completes the material removal processing of the fiber layer with a thickness of 0.1mm in the θ3=90° direction and a diameter of φ220mm and a width of 6mm in the circumferential range.

[0060] S16: Repeat S7-S9 from the outside to the inside to complete the processing and removal of the φ220mm diameter fiber θ3=90° 90° cutting layer. The circumferential diameter of the linear interpolation is reduced by 12mm. Therefore, S7 to S9 need to be repeated 19 times to complete the processing of the entire fiber layer with a thickness of 0.1mm.

[0061] S17: The computer control system 1 drives the camera 6 to take pictures and calculate the direction of the unremoved surface fibers, and compares the direction with the original stored fiber layer direction θ3=90°. If the direction of the unprocessed fiber layer surface is consistent with the fiber layer direction recorded in the control system, then continue to execute S7-S9 to complete the removal of the fiber layer material in the same direction θ3=90° with a diameter of 220mm and a circumferential thickness of 0.3mm.

[0062] S18: When the fiber layer direction calculated by the computer control system 1 and the camera system 6 is inconsistent with the previous layer, it is determined that the fiber layup direction θ4=45° is the fiber 45° cutting layer 21. The computer control system 1 retrieves the processing path CAM code for the next fiber layer direction and repeats steps S7-S9 to complete the material removal processing of the fiber layer with a thickness of 0.1mm in the θ4=45° direction and a diameter of φ180mm and a width of 6mm within the circumference.

[0063] S19: Repeat S7-S9 from the outside to the inside to complete the processing and removal of the φ180mm diameter θ4=45 fiber 45° cutting layer 21 fiber layer. The circumferential diameter of the linear interpolation is reduced by 12mm. Therefore, S7 to S9 needs to be repeated 15 times to complete the processing of the entire fiber layer with a thickness of 0.1mm.

[0064] S20: The computer control system 1 drives the camera 6 to take pictures and calculate the direction of the unremoved surface fibers, and compares the direction with the original stored fiber layer direction θ4=45° fiber 45° cut layer 21. If the direction of the unprocessed fiber layer surface is consistent with the fiber layer direction recorded in the control system, then continue to execute S7-S9 to complete the processing of the 140mm diameter circumference of the fiber layer material in the same direction θ4=45°.

[0065] S21: When the fiber layer direction calculated by the computer control system 1 driving the camera system 6 is inconsistent with the previous layer, it is determined that the fiber layup direction θ5 = 0°, fiber 0° cutting layer 22, and the computer control system 1 retrieves the CAM code for the processing path of the next fiber layer direction, with coordinates as follows: Repeat steps S7-S11 to complete the material removal process of the fiber layer with a thickness of 0.1 mm in the θ5=0° direction and a circumference of 6 mm in the φ100 mm diameter area.

[0066] S22: Repeat S7-S9 from the outside to the inside to complete the processing and removal of the φ100mm diameter θ5=0°-22 fiber layer. The circumferential diameter formed by linear interpolation is reduced by 12mm. Therefore, S7 to S9 need to be repeated 9 times to complete the processing of the entire fiber layer with a thickness of 0.1mm.

[0067] S23: The computer control system 1 drives the camera 6 to take pictures and calculate the direction of the unremoved surface fibers, and compares the direction with the original stored fiber layer direction θ5=0°. If the direction of the unprocessed fiber layer surface is consistent with the fiber layer direction recorded in the control system, then continue to execute S7-S9 to complete the removal of the fiber layer material in the same direction θ5=0°, with a fiber diameter of φ100mm and a thickness of 0.4mm.

[0068] S24: After executing the CAM code for processing and removing damaged material from all defective areas, the drive system drives the intelligent camera according to the relevant... The coordinate path is photographed, and the photographed processing area is fitted and processed to obtain the complete shape of the damaged processing area patch. The fiber layup direction θi with a specific processing thickness is recorded and organized to form a complete damage defect area patch parameter image 23, which is recorded inside the computer control system 1.

[0069] S25: The computer control system 1 turns on the vacuum adsorption system 2. After the vacuum suction cup is released, the automated removal system is removed from the free curvature surface 14 of the composite structure and placed in the designated position.

[0070] Implementation Case 2: The specific steps of the rectangular step-shaped damage removal process are similar to those in S1-S28. The main difference is that the initial processing CAM code planned in the processing implementation stage is different. The other related algorithms and detection methods adopt the relevant steps and methods in S1-S25.

[0071] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, features defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more. In the description of this invention, "above" or "below" a second feature may include direct contact between the first and second features, or it may include contact between the first and second features not being in direct contact but through another feature between them.

[0072] In the description of this invention, the terms "above," "over," and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicating that the first feature is at a higher horizontal level than the second feature.

[0073] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0074] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0075] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An automated removal process for damaged areas in continuous fiber composite materials, characterized in that, Includes the following steps: S1, the composite material structure (11) to be processed is installed below the multi-degree-of-freedom motion system (3) by the vacuum suction cup assembly (2). The composite material structure (11) has a damaged defect area (10). The multi-degree-of-freedom motion system (3) is equipped with a high-speed cutting tool (13) and a camera (6). S2, the damaged defect area (10) of the composite material structural component (11) is decomposed into multiple discrete points to obtain the coordinates of each discrete point; the multi-degree-of-freedom motion system (3) sets the distance between the high-speed cutting tool (13) and the damaged defect area (10) as a reserved installation distance; based on the coordinates of each discrete point, the high-speed cutting tool (13) moves along the maximum envelope size of the pre-set CAM path; S3, calculate the coordinates of each discrete point in the damaged defect area (10) after removing the paint layer thickness; S4, collect the height parameters of each discrete point in the damaged defect area (10), and combine them with the paint layer thickness to obtain the processing data point coordinates of each discrete point in the damaged defect area (10) after removing the paint layer thickness; S5, the multi-degree-of-freedom motion system (3) drives the high-speed cutting tool (13) to process the surface paint layer of the damaged defect area (10) in a linear interpolation manner according to the coordinates of the processing data points, and remove the surface paint layer; S6, the camera (6) takes pictures of the damaged defect area (10) to obtain the fiber layer laying direction; based on the processing data point coordinates of each discrete point obtained in S4, combined with the thickness of the fiber layer laying, the fiber cutting data coordinate points are obtained; S7, the high-speed cutting tool (13) processes the fiber layer of the damaged defect area (10) according to the fiber cutting data coordinate points; S8. Take a picture of the damaged defect area (10) where the surface fiber layer has not been removed by the camera (6) to obtain the fiber layer laying direction. Compare the fiber layer laying direction with the original fiber layer laying direction obtained in S6. If they are consistent, repeat S7 until the fiber layer in the same direction is removed. Otherwise, execute S9. S9, the computer control system (1) retrieves the CAM code for the processing path of the next fiber layer, repeats S6-S8, and completes the processing of the next fiber layer; S10, repeat S9 until all fiber layers in the damaged defect area (10) are removed; S11, take a picture of the damaged defect area (10) with a camera (6) to obtain a complete patch parameter image of the damaged processing area (10) and store it, and the processing ends.

2. The automatic removal processing method for damaged repair areas of continuous fiber composite materials according to claim 1, characterized in that, In S2, the path of the processing pattern of the damage defect area (10) is composed of line segments. After the line segments are discretized, the coordinates of each discrete point are obtained.

3. The automatic removal processing method for damaged repair areas of continuous fiber composite materials according to claim 1, characterized in that, In S2, the multi-degree-of-freedom motion system (3) moves the high-speed cutting tool (13) to the highest point of the damage defect area (10), and uses the coordinates of the highest point after removing the paint layer thickness as the machining start point.

4. The automatic removal processing method for damaged repair areas of continuous fiber composite materials according to claim 1, characterized in that, During the surface coating process, S5 follows a path from the maximum envelope size to the minimum envelope size.

5. The automatic removal processing method for damaged repair areas of continuous fiber composite materials according to claim 1, characterized in that, S6, during the process of obtaining the fiber layer laying direction, half of the processed photos are fitted to obtain the fiber layer laying direction.

6. The automatic removal processing method for damaged repair areas of continuous fiber composite materials according to claim 1, characterized in that, In S6, the formula for calculating the fiber cutting coordinate points is: ， in, , and These are the coordinates of the discrete points being measured. This refers to the thickness of a single fiber layup. Paint layer thickness, The Z-axis height of the data point relative to the fiber surface is typically 0.2mm-0.4mm thick.

7. The automatic removal processing method for damaged repair areas of continuous fiber composite materials according to claim 1, characterized in that, During S7, the fiber layer processing path for the damaged defect area (10) is a path that gradually shrinks from the maximum external size or gradually expands from the minimum size.

8. The automatic removal processing method for damaged repair areas of continuous fiber composite materials according to claim 1, characterized in that, During the S2-S9 process, dust is collected through negative pressure.

9. The automatic removal processing method for damaged repair areas of continuous fiber composite materials according to claim 1, characterized in that, During the process of S2-S9, the width of each machining operation is the width of the high-speed cutting tool (13).

10. An automatic removal device for damaged repair areas of continuous fiber composite materials used to implement the processing method of claim 1, characterized in that, The system includes a multi-degree-of-freedom motion system (3), which is mounted on a composite material structure (11) via a vacuum suction cup assembly (2); the lower end of the multi-degree-of-freedom motion system (3) is connected to a high-speed rotating spindle (4), and the front end of the high-speed rotating spindle (4) is equipped with a negative pressure collection hood (5) and a high-speed cutting tool (13), which is located in the negative pressure collection hood (5); a camera (6), an ultrasonic thickness gauge (9), and a laser rangefinder (7) are mounted on the high-speed rotating spindle (4); the negative pressure collection hood (5) is connected to a dust collector (8-1) via a dust collection pipe (8-2); The multi-degree-of-freedom motion system (3), vacuum suction cup assembly (2) and dust collector (8-1) are all electrically connected to the computer control system (1).

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