A carbon fiber composite material damage detection system and method

Abstract

The application discloses a kind of carbon fiber composite material damage detection systems, comprising: mechanical arm, first group of measuring plate, second group of measuring plate, constant current source, ammeter and processor;First group of measuring plate and second group of measuring plate include two measuring plate components, two measuring plate components in first group of measuring plate are respectively arranged on the top surface and bottom surface of carbon fiber composite material;Two measuring plate components in second group of measuring plate are respectively arranged on two opposite sides of carbon fiber composite material;Mechanical arm controls first group of measuring plate and second group of measuring plate to move on carbon fiber composite material respectively;The output end of one measuring plate component is connected with the positive pole of constant current source, and ammeter is connected between the negative pole of constant current source and the output end of another measuring plate component;Processor obtains carbon fiber composite material damage position coordinates according to the current data obtained.This application improves the efficiency and accuracy of composite material damage detection, greatly reduces the related cost, and at the same time enhances the safety and reliability of material use.

Description

Technical Field

[0001] This invention relates to the field of material damage detection technology, and in particular to a damage detection system and method for carbon fiber composite materials. Background Technology

[0002] The carbon fiber composite materials industry is experiencing a golden age of rapid development. It is not only a key force driving industrial upgrading but also a typical representative of new quality productivity. Carbon fiber composites possess advantages such as high specific strength, high specific modulus, and excellent designability, and are widely used in many cutting-edge fields, including aerospace, marine vehicles, consumer electronics, construction engineering, and robotics manufacturing. However, potential structural defects are inevitable in the manufacturing process of carbon fiber composites, and internal fiber breakage and aging phenomena are unavoidable during long-term service. These potential damages are often not visible to the naked eye, but they can reduce the mechanical strength of the material by more than half, seriously threatening the structural stability of the composite material. Therefore, there is an urgent need to develop a technical measure that can non-destructively detect potential damage in carbon fiber composites and evaluate their mechanical properties.

[0003] In the field of non-destructive testing of carbon fiber composite materials, the most widely used non-destructive testing methods include ultrasonic testing, CT testing, acoustic emission testing, and infrared thermography.

[0004] Invention patent CN202211360912.0 discloses an ultrasonic quantitative assessment device and method for impact damage of carbon fiber composite materials. This invention provides an ultrasonic detection method for damage in carbon fiber composite materials, which can quantitatively analyze defects and evaluate mechanical properties, achieving rapid and accurate quantitative detection of impact damage defects in carbon fiber composite materials. However, this method has a relatively complex system, high operation and maintenance costs, is easily affected by environmental factors, and has high requirements for the detection environment.

[0005] Invention patent CN202110470207.5 discloses a non-destructive testing method for composite material defects based on generative thermal imaging. This repair method combines thermal imaging technology with a generative adversarial network model to achieve feature extraction and background reduction of thermal image data, thereby improving the accuracy and reliability of infrared thermal imaging detection of internal defects in polymers. However, this method also has some limitations, such as long damage detection time, planar image results, and low detection accuracy.

[0006] Invention patent CN202010821919.2 discloses an experimental method for studying the tensile fatigue damage evolution of carbon fiber / epoxy resin three-dimensional woven composite materials based on synchrotron radiation CT. This method uses synchrotron radiation CT for damage detection, enabling damage observation of three-dimensional woven composite materials. However, the method is relatively cumbersome to operate, requires a long testing time and high material costs, and is difficult to implement for operators without relevant skills. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides a carbon fiber composite material damage detection system and method to solve technical problems such as high maintenance costs, susceptibility to interference during detection, low detection accuracy, and cumbersome detection process.

[0008] This invention provides a carbon fiber composite material damage detection system, comprising: a robotic arm, a first set of test plates, a second set of test plates, a constant current source, an ammeter, and a processor;

[0009] Both the first and second test plates consist of two test plate assemblies. The two test plate assemblies in the first set are respectively positioned on the top and bottom surfaces of the carbon fiber composite material; the two test plate assemblies in the second set are respectively positioned on two opposite sides of the carbon fiber composite material. Each test plate assembly includes: a flat plate, copper test points, connecting posts, and a circuit controller. Several copper test points are evenly distributed on the side of the flat plate that contacts the carbon fiber composite material. The connecting posts are vertically positioned on the other side of the flat plate that contacts the carbon fiber composite material. The circuit controller is connected to several copper test points and is used to adjust the connection between the copper test points to be series or parallel. A robotic arm is connected to the connecting posts and controls the movement of the first set of test plates on the top and bottom surfaces of the carbon fiber composite material. The robotic arm also controls the horizontal movement of the second set of test plates on two opposite sides of the carbon fiber composite material. The output terminal of the circuit controller on one side of each test plate assembly is connected to the positive terminal of a constant current source, and an ammeter is connected in series between the negative terminal of the constant current source and the output terminal of the circuit controller on the other side. A processor is connected to the ammeter and is used to obtain the coordinates of the damage location of the carbon fiber composite material based on the acquired current data.

[0010] Furthermore, the carbon fiber composite material damage detection system also includes a resistor; the resistor is connected in series between the output terminal of the circuit controller on one side and the positive terminal of the constant current source.

[0011] Furthermore, the distribution of copper measuring points on the plate corresponds to the carbon fiber bundles in the carbon fiber composite material.

[0012] The present invention also provides a detection method for a carbon fiber composite material damage detection system, comprising:

[0013] Step 1: Grind the surface of the carbon fiber composite material until the carbon fiber bundles are exposed;

[0014] Step 2: Apply a conductive coating to the surface of the carbon fiber composite material;

[0015] Step 3: Construct a three-dimensional coordinate system, with the carbon fiber bundle extension direction as the y-axis, the horizontal direction perpendicular to the carbon fiber bundle extension direction as the x-axis, and the height direction of the carbon fiber composite material as the z-axis.

[0016] The process of coarsely measuring the damaged area is as follows:

[0017] The copper measuring points are set to be connected in parallel. The coarse coordinates of the damaged area are obtained based on the moving speed of the first set of measuring plates and the second set of measuring plates and the collected current.

[0018] Step 4: Perform a precise measurement of the damaged area. The specific process is as follows:

[0019] The copper measuring points are set up in series, and the precise coordinates of the damaged area are obtained based on the moving speed of the first and second sets of measuring boards and the collected current.

[0020] Furthermore, following step 4, a mechanical damage assessment process is also included.

[0021] Furthermore, the specific method for obtaining the coarse coordinates of the damaged area in step 3 is as follows:

[0022] Step 31: Control the second set of measuring plates to move along the x-axis at a preset speed and collect the current data at each moment;

[0023] Step 32: Construct a coordinate system of current and time, and obtain the start and end times of current fluctuations that exceed the preset fluctuation amount;

[0024] Step 33: Calculate the starting and ending coordinates of the damaged area along the x-axis based on the preset speed movement and the start and end times of the current fluctuation;

[0025] Step 34: Control the first set of measuring plates to move at a preset speed along the y-axis within the x-axis range of the coordinates obtained in step 33, and collect the current data at each moment;

[0026] Step 35: Construct a coordinate system of current and time, and obtain the start and end times of current fluctuations that exceed the preset fluctuation amount;

[0027] Step 36: Calculate the starting and ending coordinates of the damaged area along the y-axis based on the preset speed movement, current fluctuation start time and end time.

[0028] Furthermore, the specific method for obtaining the precise coordinates of the damaged area in step 4 is as follows:

[0029] Step 41: Control the second set of measuring plates to move at a preset speed between the starting and ending coordinates in the x-axis direction of the damaged area, and collect the current data of each copper measuring point at each moment.

[0030] Step 42: Control the first set of measuring plates to move between the starting and ending coordinates in the y-axis direction of the damaged area at a preset speed, and collect the current data of each copper measuring point at each moment;

[0031] Step 43: Obtain the coordinates of the copper measuring point corresponding to the current exceeding the preset error;

[0032] Step 44: Construct a spatial three-dimensional network of current distribution in the damaged area based on the coordinates obtained in Step 43, with each grid corresponding to two current values.

[0033] Furthermore, step 36 is followed by a verification process, the specific steps of which are as follows:

[0034] Step 37: Control the first set of measuring plates along the x-axis direction within the x-axis range of the coordinates obtained in step 33, and collect the current data at each moment;

[0035] Step 38: Construct a coordinate system of current and time, and obtain the start and end times of current fluctuations that exceed the preset fluctuation amount;

[0036] Step 39: Calculate the starting and ending coordinates of the damaged area along the x-axis based on the preset speed movement, the start time and end time of the current fluctuation;

[0037] Step 310: When the coordinates obtained in step 39 are the same as the coordinates obtained in step 33, the verification is complete;

[0038] When the coordinates obtained in step 39 are different from those obtained in step 33, the first set of measuring plates is controlled to move in a serpentine manner with the coordinate system 0 as the starting point and the movement along the x-axis as the initial direction; the current fluctuation time with a current fluctuation rate greater than 5% in multiple segments is obtained, and the plane coordinates corresponding to the damaged area are calculated.

[0039] Furthermore, the mechanical damage assessment process includes the following steps:

[0040] Step 51: Perform resistivity conversion on the two current values ​​corresponding to each grid obtained in Step 44;

[0041] Step 52: Construct a macroscopic mechanical property static experiment to obtain experimental data on resistivity and mechanical property damage;

[0042] Step 53: Construct a finite element model and obtain simulation data on resistivity and mechanical property damage;

[0043] Step 54: Use the experimental data obtained in Step 52 and the simulation data obtained in Step 53 as the training set for the mechanical damage assessment model to train the mechanical damage assessment model.

[0044] Step 55: Use the resistivity obtained in Step 51 to obtain the mechanical damage assessment results of the carbon fiber composite material through the trained mechanical damage assessment model.

[0045] The beneficial effects of this invention are:

[0046] This invention greatly simplifies the damage detection process through automated operation, eliminates reliance on highly skilled operators, reduces labor costs, and improves the consistency and reliability of detection. It not only improves work efficiency but also ensures the accuracy of detection results.

[0047] The equipment required for this invention is simple and inexpensive, significantly reducing the time and economic costs of testing. This low-cost, high-efficiency solution enables more enterprises and research institutions to implement high-quality damage testing services, promoting the application and development of composite materials.

[0048] This invention enables three-dimensional assessment of internal damage, providing crucial support for a comprehensive understanding of the damage status of composite materials. Through precise three-dimensional analysis, this invention can more accurately predict the overall mechanical properties of materials, thus providing a scientific basis for subsequent repair or replacement decisions.

[0049] Based on detailed damage assessment results, this invention enables targeted maintenance strategies, such as local replacement or reinforcement, to be implemented for specific damage conditions in different areas. This not only improves the efficiency and effectiveness of maintenance work but also ensures the performance stability and safety of composite materials during service, extends the material's lifespan, and reduces safety hazards and economic losses caused by sudden failures.

[0050] This invention, through its innovative detection methods and technologies, not only improves the efficiency and accuracy of composite material damage detection, but also significantly reduces related costs, while enhancing the safety and reliability of material use. It has significant application value and broad market prospects. Attached Figure Description

[0051] The features and advantages of the invention will be more clearly understood by referring to the accompanying drawings, which are schematic and should not be construed as limiting the invention in any way. In the drawings:

[0052] Figure 1 This is a schematic diagram of the initial position of the first set of measuring plates in a specific embodiment of the present invention;

[0053] Figure 2 This is a schematic diagram of the initial position of the second set of measuring plates in a specific embodiment of the present invention;

[0054] Figure 3 This is a schematic diagram of the test plate assembly in a specific embodiment of the present invention;

[0055] Figure 4 This is a schematic diagram of the serpentine movement path of the first set of test plates during the verification process in a specific embodiment of the present invention. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0057] The present invention will be further illustrated below with reference to specific embodiments. Those skilled in the art should understand that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Modifications to the present invention in various equivalent forms all fall within the scope defined by the appended claims.

[0058] like Figure 1-4 As shown, the present invention provides a carbon fiber composite material damage detection system, including: a robotic arm 1, a first set of measuring plates 2, a second set of measuring plates 7, a constant current source 10, a resistor 9, an ammeter 11, and a processor 12;

[0059] Both the first set of measuring plates 2 and the second set of measuring plates 7 include two measuring plate assemblies. The two measuring plate assemblies in the first set of measuring plates 2 are respectively disposed on the top and bottom surfaces of the carbon fiber composite material 5. The two measuring plate assemblies in the second set of measuring plates 7 are respectively disposed on two opposite sides of the carbon fiber composite material 5. The measuring plate assembly includes: a flat plate 105, copper measuring points 101, a connecting post 103, and a circuit controller 104. Several copper measuring points 101 are evenly distributed on the side of the flat plate 105 that contacts the carbon fiber composite material 5. The distribution of the copper measuring points 101 on the flat plate 105 corresponds to the carbon fiber bundles in the carbon fiber composite material 5, corresponding to the thickness of a single layer of carbon fiber layup, which is generally 0.2mm*0.2mm.

[0060] A connecting post 103 is vertically positioned on the other side of the plate 105 that contacts the carbon fiber composite material 5. A circuit controller 104 is connected to several copper measuring points 101 via internal wires 102. The circuit controller 104 is used to adjust the connection between the copper measuring points 101 to be in series or in parallel. A robotic arm 1 is connected to the connecting post 103. The robotic arm 1 controls the movement of the first set of measuring plates 2 on the top and bottom surfaces of the carbon fiber composite material 5. The robotic arm 1 controls the horizontal movement of the second set of measuring plates 7 on two opposite sides of the carbon fiber composite material 5. A resistor 9 is connected in series between the output terminal of the circuit controller 104 on one side of the two measuring plate assemblies and the positive terminal of the constant current source 10. An ammeter 11 is connected in series between the negative terminal of the constant current source 10 and the output terminal of the circuit controller 104 on the other side. A processor 12 is connected to the ammeter 11 and is used to obtain the coordinates of the damage location of the carbon fiber composite material 5 based on the acquired current data.

[0061] Figure 1 In the process, the first set of measuring plates 2 moves along the X-axis and Y-axis respectively, forming a cross shape, and the moving path 3 passes through the damaged position 4. Figure 2 In the diagram, the second set of measuring plates 7 moves along the X-axis layer by layer in the Z-axis direction. Figure 4 In the middle, the movement path 3 of the first set of measuring plates 2 is serpentine.

[0062] The present invention also provides a detection method for a carbon fiber composite material damage detection system, comprising:

[0063] Step 1: Grinding is required in both the direction parallel to the fiber layer and the direction perpendicular to the cross section to expose the carbon fiber bundles in the carbon fiber composite material and make the ground surface smooth.

[0064] Step 2: A conductive coating 6 is applied between the surface of the carbon fiber composite material and the flat plate to facilitate uniform translation of the flat plate;

[0065] The circuit internal resistance is measured, specifically as follows:

[0066] Horizontal current I is obtained by shorting the two ends of the second set of measuring plates and the first set of measuring plates respectively. x0 and vertical current I y0 Given the output voltage V0 of the constant current source, the internal resistance R of the circuit can be easily calculated using Ohm's law. x0 and R y0 ;

[0067] Step 3: Construct a three-dimensional coordinate system, with the carbon fiber bundle extension direction as the y-axis, the horizontal direction perpendicular to the carbon fiber bundle extension direction as the x-axis, and the height direction of the carbon fiber composite material as the z-axis.

[0068] The coarse measurement process of the damaged area is performed by setting the copper measuring points in parallel. The precise coordinates of the damaged area are obtained based on the moving speed of the first and second sets of measuring boards and the collected current. The specific process is as follows:

[0069] Step 31: Control the second set of measuring plates along the x-axis at a preset speed v x Move it and collect current data at every moment;

[0070] Step 32: Construct a coordinate system of current and time, and obtain the start time t of current fluctuations with a current fluctuation rate greater than 5%. x1 With end time t x2 Current fluctuations less than 5% are considered systematic errors.

[0071] Step 33: Calculate the initial coordinate v of the damaged area in the horizontal direction based on the preset speed movement, the start time and end time of the current fluctuation. x t x1 With the end coordinate v x t x2 ;

[0072] Step 34: Control the first set of measuring plates along the y-axis direction within the x-axis range of the coordinates obtained in step 33, at a preset speed v. y Move it and collect current data at every moment;

[0073] Step 35: Construct a coordinate system of current and time, and obtain the start time t of current fluctuation exceeding the preset fluctuation amount. y1 With end time t y2 ;

[0074] Step 36: Calculate the initial coordinate v of the damaged area along the y-axis based on the preset speed movement, the start time and end time of the current fluctuation. y t y1 With the end coordinate v y t y2 ;

[0075] Step 37: Control the first set of measuring plates along the x-axis direction within the x-axis range of the coordinates obtained in step 33, and collect the current data at each moment;

[0076] Step 38: Construct a coordinate system of current and time, and obtain the start time t of current fluctuation exceeding the preset fluctuation amount. yx1 With end time t yx2 ;

[0077] Step 39: Calculate the initial coordinate v of the damaged area along the x-axis based on the preset speed movement, the start time and end time of the current fluctuation. x t yx1 Target and end coordinates vx t yx2 ;

[0078] Step 310: When the coordinates obtained in step 39 are the same as the coordinates obtained in step 33, the verification is complete;

[0079] When the coordinates obtained in step 39 are different from the coordinates obtained in step 33, such as Figure 4 As shown, starting from point 0 of the coordinate system, the first set of measuring plates is controlled to move in a serpentine pattern with the initial direction of movement along the x-axis; the moving speed is v, and the current fluctuation time t1~t2, t2~t3, …t3~t is recorded for multiple segments with a current fluctuation rate greater than 5%. n Then, the planar coordinates corresponding to the damaged area are calculated based on the moving path of the measuring plate and the geometric dimensions of the material.

[0080] Step 4: Perform precise measurement of the damaged area. The copper measuring points are connected in series. Based on the moving speeds of the first and second sets of measuring boards and the collected current, the precise coordinates of the damaged area are obtained. The specific process is as follows:

[0081] Step 41: Control the second set of measuring plates to move at a preset speed between the starting and ending coordinates in the x-axis direction of the damaged area, and collect the current data of each copper measuring point at each moment.

[0082] Step 42: Control the first set of measuring plates to move between the starting and ending coordinates in the y-axis direction of the damaged area at a preset speed, and collect the current data of each copper measuring point at each moment;

[0083] Step 43: Using 5% as the error, the part where the current is significantly higher or lower than the undamaged area is considered damaged. Obtain the coordinates of the copper measuring point corresponding to the current exceeding 5%.

[0084] Step 44: Construct a spatial three-dimensional network of current distribution in the damaged area based on the coordinates obtained in Step 43. Each grid cell corresponds to two current values, with the horizontal y-axis as the dividing line. and the direction perpendicular to the x-axis

[0085] Step 5: Mechanical damage assessment process, including the following steps:

[0086] Step 51: Perform resistivity conversion on the two current values ​​corresponding to each grid obtained in Step 44;

[0087] First, in the horizontal y-axis direction... and the direction perpendicular to the x-axis Convert each component to resistivity to eliminate the influence of material size; the overall resistance can then be obtained using Ohm's law. and Then subtract the circuit internal resistance R from step 2. x0 and R y0 Then, according to the resistivity formula:

[0088] ρ = RS / L

[0089] In the formula, S is the area of ​​the copper measuring point 101; L is the length of the carbon fiber and the thickness of the sample, respectively.

[0090] The corresponding resistivity can then be obtained. and These represent carbon fiber damage and interlaminar damage, respectively.

[0091] Step 52: Construct a macroscopic mechanical property static experiment to obtain experimental data on resistivity and mechanical property damage;

[0092] Carbon fiber / epoxy resin unidirectional reinforced composite material samples with different carbon fiber contents and different layup thicknesses were designed and fabricated as equivalent substitutes. Then, static mechanical tests were carried out on these homogeneous samples to obtain the elastic modulus in the horizontal direction and the layup direction. Using the carbon fiber composite material as the reference elastic modulus E0, the damage coefficient of mechanical properties D = ΔE / E0 was calculated. Finally, the resistivity of these samples in the horizontal direction and the layup direction was measured to obtain experimental data on the resistivity and mechanical property damage of the unidirectional reinforced composite material samples.

[0093] Step 53: Construct a finite element model and obtain simulation data on resistivity and mechanical property damage;

[0094] Combining the elastoplastic constitutive equation and the damage mechanics theoretical model, the finite element model was used to simulate and calculate the resistivity and mechanical property damage of different carbon fiber / epoxy resin monolayer composite samples, which serves as a supplement to the experimental data in step 52.

[0095] Step 54: Use the experimental data obtained in Step 52 and the simulation data obtained in Step 53 as the training set for the mechanical damage assessment model. Feed them into the mechanical damage assessment model with artificial neural network for deep learning, so as to obtain the mechanical damage assessment model of composite material along the carbon fiber direction and the layup direction corresponding to any horizontal and vertical resistivity.

[0096] Step 55: Use the resistivity obtained in step 51 and The mechanical damage assessment results of carbon fiber composite materials are obtained by using a trained mechanical damage assessment model, thereby generating a spatial distribution cloud map of the damage of the entire carbon fiber composite material sample under test.

[0097] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A damage detection system for carbon fiber composite materials, characterized in that, include: Robotic arm, first set of measuring plates, second set of measuring plates, constant current source, ammeter and processor; Both the first and second sets of test plates include two test plate assemblies. The two test plate assemblies in the first set are respectively positioned on the top and bottom surfaces of the carbon fiber composite material and are arranged opposite each other. The two test plate assemblies in the second set are respectively positioned on two opposite sides of the carbon fiber composite material. Each test plate assembly includes: a flat plate, copper test points, connecting posts, and a circuit controller. Several copper test points are evenly distributed on the side of the flat plate that contacts the carbon fiber composite material, and the distribution of the copper test points on the flat plate corresponds to the carbon fiber bundles in the carbon fiber composite material. The connecting posts are vertically positioned on the other side of the flat plate that contacts the carbon fiber composite material. The circuit controller... The controller is connected to several copper measuring points. The circuit controller is configured to switch between parallel coarse measurement and series fine measurement states for the multiple copper measuring points. The robotic arm is connected to the connecting column and controls the first set of measuring plates to move synchronously on the top and bottom surfaces of the carbon fiber composite material. The robotic arm controls the second set of measuring plates to scan layer by layer along the x-axis at different z-axis positions on two opposite sides of the carbon fiber composite material. The output terminal of the circuit controller on one side of the two measuring plate assemblies is connected to the positive terminal of the constant current source, and the ammeter is connected in series between the negative terminal of the constant current source and the output terminal of the circuit controller on the other side. The processor is connected to the ammeter. In parallel coarse measurement mode, the robotic arm drives the second set of measuring plates to move layer by layer along the x-axis at different z-axis positions, and drives the first set of measuring plates to move along the y-axis. The processor determines the three-dimensional coarse coordinates of the damaged area based on the moving position of the measuring plates and the collected current changes. In the series precision measurement state, the robotic arm drives the first and second sets of measuring plates to move within the range defined by the three-dimensional coarse coordinates. The processor acquires the current data corresponding to each copper measuring point and constructs a three-dimensional current distribution network of the damaged area. Each grid corresponds to the current value in two different detection directions.

2. The carbon fiber composite material damage detection system as described in claim 1, characterized in that, The carbon fiber composite material damage detection system also includes a resistor; the resistor is connected in series between the output terminal of the circuit controller on one side and the positive terminal of the constant current source.

3. A detection method for a carbon fiber composite material damage detection system, applicable to the carbon fiber composite material damage detection system as described in claim 1 or 2, characterized in that, The method includes the following steps: Step 1: Grind the surface of the carbon fiber composite material until the carbon fiber bundles are exposed; Step 2: Apply a conductive coating to the surface of the carbon fiber composite material; short-circuit the first set of test plates and the second set of test plates respectively before testing to obtain the circuit internal resistance in two testing directions; Step 3: Construct a three-dimensional coordinate system, with the carbon fiber bundle extension direction as the y-axis, the horizontal direction perpendicular to the carbon fiber bundle extension direction as the x-axis, and the height direction of the carbon fiber composite material as the z-axis. The process of coarsely measuring the damaged area is as follows: The copper measuring points are set to be connected in parallel. The coarse coordinates of the damaged area are obtained based on the moving speed of the first and second sets of measuring boards and the collected current. The specific method for obtaining the coarse coordinates of the damaged area is as follows: Step 31: Control the second set of measuring plates to move sequentially along the x-axis at different z-axis positions of the carbon fiber composite material at a preset speed, and collect the current data at each moment; Step 32: Construct a coordinate system of current and time, and obtain the start and end times of current fluctuations that exceed the preset fluctuation amount; Step 33: Calculate the starting and ending coordinates of the damaged area along the x-axis based on the preset speed movement, the start time and end time of the current fluctuation, and determine the coarse coordinates of the damaged area along the z-axis based on the current z-axis position; Step 34: Control the first set of measuring plates to move at a preset speed along the y-axis within the x-axis range of the coordinates obtained in step 33, and collect the current data at each moment; Step 35: Construct a coordinate system of current and time, and obtain the start and end times of current fluctuations that exceed the preset fluctuation amount; Step 36: Calculate the starting and ending coordinates of the damaged area along the y-axis based on the preset speed movement, current fluctuation start time and end time; Step 4: Perform a precise measurement of the damaged area. The specific process is as follows: The copper measuring points are set up in series. The precise coordinates of the damaged area are obtained based on the moving speed of the first and second sets of measuring boards and the collected current. The specific method for obtaining the precise coordinates of the damaged area is as follows: Step 41: Control the second set of measuring plates to move at a preset speed between the starting and ending coordinates in the x-axis direction of the damaged area, and collect the current data of each copper measuring point at each moment. Step 42: Control the first set of measuring plates to move between the starting and ending coordinates in the y-axis direction of the damaged area at a preset speed, and collect the current data of each copper measuring point at each moment; Step 43: Obtain the coordinates of the copper measuring point corresponding to the current exceeding the preset error; Step 44: Construct a spatial three-dimensional network of current distribution in the damaged area based on the coordinates obtained in Step 43, with each grid corresponding to two current values; Step 45: After converting the detection current into the total resistance in the corresponding direction, subtract the circuit internal resistance in the corresponding direction, and then calculate the resistivity of the carbon fiber composite material so that each grid corresponds to the resistivity value in two different detection directions.

4. The detection method of the carbon fiber composite material damage detection system as described in claim 3, characterized in that, The process following step 4 includes a mechanical damage assessment.

5. The detection method of the carbon fiber composite material damage detection system as described in claim 3, characterized in that, Following step 36, a verification process is also included, the specific steps of which are as follows: Step 37: Control the first set of measuring plates along the x-axis direction within the x-axis range of the coordinates obtained in step 33, and collect the current data at each moment; Step 38: Construct a coordinate system of current and time, and obtain the start and end times of current fluctuations that exceed the preset fluctuation amount; Step 39: Calculate the starting and ending coordinates of the damaged area along the x-axis based on the preset speed movement, the start time and end time of the current fluctuation; Step 310: When the coordinates obtained in step 39 are the same as the coordinates obtained in step 33, the verification is complete; When the coordinates obtained in step 39 are different from those obtained in step 33, the first set of measuring plates is controlled to move in a serpentine manner with the coordinate system 0 as the starting point and the movement along the x-axis as the initial direction. Obtain the current fluctuation time of multiple segments with a current fluctuation rate greater than 5%, and calculate the planar coordinates corresponding to the damaged area.

6. The detection method of the carbon fiber composite material damage detection system as described in claim 4, characterized in that, The mechanical damage assessment process includes the following steps: Step 51: Perform resistivity conversion on the two current values ​​corresponding to each grid obtained in Step 44; Step 52: Construct a macroscopic mechanical property static experiment to obtain experimental data on resistivity and mechanical property damage; Step 53: Construct a finite element model and obtain simulation data on resistivity and mechanical property damage; Step 54: Use the experimental data obtained in Step 52 and the simulation data obtained in Step 53 as the training set for the mechanical damage assessment model to train the mechanical damage assessment model. Step 55: Use the resistivity obtained in Step 51 to obtain the mechanical damage assessment results of the carbon fiber composite material through the trained mechanical damage assessment model.

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