Impact load monitoring and positioning method for carbon fiber winding shell

Abstract

The invention belongs to the technical field of carbon fiber shell health monitoring, and particularly relates to a carbon fiber winding shell impact load monitoring and positioning method. The positioning method comprises the following steps that at least one FBG optical fiber sensor array is arranged for a carbon fiber winding shell; when the carbon fiber winding shell is prepared, the FBG optical fiber sensor array is embedded in the carbon fiber winding shell; obtaining a reference response signal of the FBG optical fiber sensor; setting an impact load FBG optical fiber sensor response threshold value, identifying the FBG optical fiber sensor responding under the impact load, and constructing an envelope line where an impact position is located; calculating an error outlier of each FBG optical fiber sensor in the envelope line; based on the error outlier obtained in the fifth step, the actual impact position is calculated and determined, positioning is rapid and accurate, and the problems that in the prior art, comprehensive nondestructive testing needs to be conducted on the carbon fiber shell frequently, time and labor are consumed, the impact position range is reduced repeatedly, and positioning is high in cost and not accurate are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of carbon fiber shell health monitoring, and in particular relates to a carbon fiber wound shell impact load monitoring and positioning method. Background Art

[0002] Carbon fiber shells are made by impregnating carbon fiber with resin and winding and curing it on a core mold. They are often used in high-pressure vessels, and their failure may cause major safety accidents. During transportation and storage, the shell is easily subjected to external impact, resulting in damage to the internal fibers and matrix. These damages are highly concealed and difficult to detect visually, but they will greatly reduce the strength of the shell, posing a serious safety hazard.

[0003] For the internal damage detection of carbon fiber shells, current technology mainly relies on traditional non-destructive testing methods such as high-frequency ultrasound and X-rays. However, since the internal damage of carbon fiber shells is difficult to identify with the naked eye, it is necessary to frequently conduct comprehensive non-destructive testing on carbon fiber shells, which is not only time-consuming and labor-intensive, but also costly. In addition, the location of the damage needs to be repeatedly narrowed down, which is time-consuming and labor-intensive, and the positioning is inaccurate.

[0004] Therefore, there is an urgent need for a method that does not require frequent comprehensive inspection of the carbon fiber shell by manual or external equipment, and can monitor and locate the impact load and position of the carbon fiber shell in real time. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the internal monitoring of carbon fiber shells in the prior art, such as complex monitoring, long time consumption, inability to monitor in real time, and inaccurate monitoring, and to provide a method for burying an FBG optical fiber sensor array in the carbon fiber shell and using an error outlier algorithm to monitor and locate the impact load position of the carbon fiber wrapped shell.

[0006] The technical solution adopted by the present invention to solve its technical problem is:

[0007] A carbon fiber wound shell impact load monitoring and positioning method comprises the following steps:

[0008] Step 1: at least one FBG optical fiber sensor array is arranged for the carbon fiber wound shell, that is, before the carbon fiber wound shell is prepared, at least one FBG optical fiber sensor array that can evenly cover the carbon fiber wound shell is arranged;

[0009] Step 2: During the preparation of the carbon fiber wound shell, the FBG optical fiber sensor array set in step 1 is buried inside the carbon fiber wound shell;

[0010] Step 3: Obtaining a reference response signal of the FBG optical fiber sensor; dividing the carbon fiber-wound shell with the embedded shell FBG optical fiber sensor array completed in step 2 into a plurality of grids, performing simulated impact loading on each grid point on the grid one by one, and obtaining the FBG optical fiber sensor response signal as the reference response signal;

[0011] Step 4: Set the response threshold of the FBG optical fiber sensor under the impact load, identify the FBG optical fiber sensor that responds under the impact load, and construct the envelope of the impact position;

[0012] Step 5: Calculate the error outliers of each FBG fiber sensor within the envelope;

[0013] Step 6: Based on the error outlier obtained in step 5, determine the actual impact position through interpolation calculation.

[0014] Specifically, the carbon fiber-wound shell is divided into a plurality of grids in step 3, including the following contents:

[0015] Any minimum array in the FBG sensor array is used as the dividing boundary;

[0016] The carbon fiber shell corresponding to the smallest array in the FBG sensor array is divided into a plurality of grids; the grids are square.

[0017] Specifically, the FBG optical fiber sensor response signal includes a central wavelength offset value signal of the FBG optical fiber sensor.

[0018] Specifically, the step 4 of constructing the envelope of the impact position includes the following contents:

[0019] The positions of the identified FBG optical fiber sensors that generate impulse responses and the identified FBG optical fiber sensors that do not generate impulse responses are determined;

[0020] Acquire a central grid point between any adjacent FBG optical fiber sensor that generates an impulse response and any adjacent FBG optical fiber sensor that does not generate an impulse response;

[0021] The envelope lines of the envelope impact positions are drawn using the obtained central grid points as boundaries.

[0022] Specifically, the calculation of the error outliers of each FBG optical fiber sensor in step 5 includes the following steps:

[0023] S401. Obtain the reference response signal corresponding to each grid point of the FBG optical fiber sensor, and pre-process the reference response signal and the actual impulse response signal to obtain a reference timing signal and three measured timing signals under three sampling times;

[0024] S402. Performing a standardization operation on a reference timing signal and the corresponding three measured timing signals;

[0025] S403. Calculate the error value between the standardized reference timing signal and the measured timing signal;

[0026] S404. Compare the calculated error value with the preset error threshold, and determine the outliers of each grid point in the envelope under three sampling times;

[0027] The preprocessing of the reference response signal in step S401 includes the following: taking the time point when the acquired reference response signal first reaches the response threshold as the starting point, taking several time points before and after, to obtain a reference timing signal; the reference timing signal includes the signal fluctuation caused by the complete impact load.

[0028] Specifically, the preprocessing of the measured response signal in step S401 includes the following steps:

[0029] Acquire a first segment of measured timing signal, that is, take the time point when the measured response signal first reaches the response threshold as the starting point, and take several time points before and after to obtain the first segment of measured timing signal; the reference timing signal and the first measured timing signal are in the same time period;

[0030] Acquire a second section of the measured time series signal, that is, advance the sampling time period of the first end measured time series signal by one time point to acquire the second section of the measured time series signal corresponding to the corresponding time period sensor;

[0031] The third section of the measured timing signal is obtained, that is, the sampling time period of the first end measured timing signal is delayed by one time point to obtain the second section of the measured timing signal corresponding to the corresponding time period sensor.

[0032] Specifically, the formula for the standardization operation in step S402 is:

[0033] S s =(SS mean ) / S std ;

[0034] Where S represents the response signal, S mean represents the average value of the response signal, S std Represents the standard deviation of the response signal.

[0035] Specifically, the calculation formula for the error value between the reference response signal after normalization and the measured impact signal in step S403 is:

[0036] E (n,1) =S Ref.(n,1) -S Test(i) ;

[0037] In the formula, S Ref.(n,1) is the reference signal value of the sensor at the ith sampling point when the nth grid point in the envelope simulates impact, S Test(i) is the actual signal value of the sensor at the i-th sampling point.

[0038] Specifically, the calculation of the actual impact position by interpolation in step 6 includes the following contents:

[0039] Arrange the outliers of each grid point in the multiple sampling time periods obtained in step 5 in ascending order;

[0040] Select the first n impact grid points in the ascending order, sum the outliers of the first n impact points, and determine the collection time period corresponding to the impact;

[0041] Arrange the outliers of each grid point in the collection time period corresponding to the impact in ascending order; obtain the first m grid points in the ascending order of the outliers in the collection time period corresponding to the impact, and use interpolation to calculate the actual impact position for the obtained m grid points; where m≥3, n≥3.

[0042] Specifically, the interpolation calculation formula for the difference in the actual impact position in step 6 is:

[0043]

[0044] Where n represents the number of selected positions, O i represents the size of the outlier at the corresponding position, represents the x-coordinate of the grid point position, Represents the y-coordinate of the grid point location.

[0045] The beneficial effects of the carbon fiber wound shell impact load monitoring and positioning method of the present invention are:

[0046] The carbon fiber wrapped shell impact load monitoring and positioning method of the present invention buries the FBG optical fiber sensor array in the shell, can monitor the data inside the shell in real time, and divides the shell into grids with the FBG optical fiber sensor as the vertex, first pre-processes and standardizes the measured response signal and the reference response signal, then uses the measured response signal of the FBG optical fiber sensor and the reference response signal error to calculate the error outlier, and finally uses the multiple minimum values ​​in the error outlier arrangement to do interpolation calculation, calculates the impact position in proportion, and realizes accurate and rapid positioning of the actual impact position. It solves the problems in the prior art that the carbon fiber shell needs to be frequently and comprehensively non-destructively tested, which is time-consuming and labor-intensive, the impact position range is repeatedly narrowed, and the positioning cost is high and inaccurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0048] Figure 1 It is a flowchart of the steps of the carbon fiber wound shell impact load monitoring and positioning method according to an embodiment of the present invention.

[0049] Figure 2 It is a partial structural diagram of a pre-embedded FBG optical fiber sensor array of a certain carbon fiber shell in an embodiment of the present invention.

[0050] Figure 3 It is a grid division diagram of the minimum array of the FBG optical fiber sensor array in the embodiment of the present invention.

[0051] Figure 4 It is a graph of response signals of four FBG optical fiber sensors corresponding to impact loading at a certain point in an embodiment of the present invention.

[0052] Figure 5 It is a schematic diagram of the envelope of the first FBG optical fiber sensor whose measured response signal exceeds the threshold value under the shell impact in the embodiment of the present invention and its corresponding impact point.

[0053] Figure 6 It is a schematic diagram of the envelope of the FBG optical fiber sensor whose second measured response signal exceeds the threshold value under the shell impact in an embodiment of the present invention and its corresponding impact point.

[0054] Figure 7 It is a comparison diagram of the errors of the corresponding signals of the same FBG optical fiber sensor at the same impact point and at different impact points in the embodiment of the present invention.

[0055] Figure 8 1 is a flow chart of calculating error outliers in an embodiment of the present invention.

[0056] Fig. 9 It is the final impact position map obtained by interpolation in the embodiment of the present invention.

[0057] Fig.10 4 is a calculation flow chart of obtaining the impact position in an embodiment of the present invention. DETAILED DESCRIPTION

[0058] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the present invention in a schematic manner, and therefore only show the components related to the present invention.

[0059] like Figure 1-Figure 10 The specific embodiment of the carbon fiber wound shell impact load monitoring and positioning method of the present invention shown includes the following steps:

[0060] Step 1: at least one FBG optical fiber sensor array is arranged for the carbon fiber wound shell, that is, before the carbon fiber wound shell is prepared, at least one FBG optical fiber sensor array that can evenly cover the carbon fiber wound shell is arranged;

[0061] Step 2: During the preparation of the carbon fiber wound shell, the FBG optical fiber sensor array set in step 1 is buried inside the carbon fiber wound shell;

[0062] Step 3: Obtaining a reference response signal of the FBG optical fiber sensor; dividing the carbon fiber-wound shell with the embedded shell FBG optical fiber sensor array completed in step 2 into a plurality of grids, performing simulated impact loading on each grid point on the grid one by one, and obtaining the FBG optical fiber sensor response signal as the reference response signal;

[0063] Step 4: Set the response threshold of the FBG optical fiber sensor under the impact load, identify the FBG optical fiber sensor that responds under the impact load, and construct the envelope of the impact position;

[0064] Step 5: Calculate the error outliers of each FBG fiber sensor within the envelope;

[0065] Step 6: Based on the error outlier obtained in step 5, determine the actual impact position through interpolation calculation.

[0066] Specifically, the carbon fiber shell in this embodiment adopts a carbon fiber wound shell, and according to the shape of the carbon fiber wound shell, one or more corresponding FBG optical fiber sensor arrays are manufactured, such as Figure 2 As shown, the FBG optical fiber sensor array can relatively evenly cover the shell, the FBG optical fiber sensor is buried in the fiber shell winding process, the optical fiber of the FBG optical fiber sensor array is led out from the shell, and connected to the collection device for collecting the strain in the shell. Multiple layers of external fiber layers are continued to be wound on the outside of the FBG optical fiber sensor array, and the external fiber layers have a protective effect on the FBG optical fiber sensor to prevent the FBG optical fiber sensor from being damaged under the impact load.

[0067] like Figure 3 As shown, the carbon fiber wrapped shell is divided into multiple grids in step three, including the following contents: taking any minimum array in the FBG sensor array as the dividing boundary, the carbon fiber shell corresponding to the minimum array in the FBG optical fiber sensor array is divided into several grids; the grid is square. It is further explained that when the carbon fiber shell is grid-divided, any minimum array in the FBG optical fiber sensor array is taken as the dividing boundary, that is, the four FBG optical fiber sensors corresponding to the minimum array are taken as the vertices of the four corners, and the shell corresponding to the four vertices is divided into 4*4 grids, and of course 5*5 grids can also be used. Here, any square grid is acceptable, and the more grids, the more accurate the positioning.

[0068] like Figure 4 As shown, simulated impact loading is performed on each grid point on the grid one by one to obtain the FBG optical fiber sensor response signal as reference data. In this embodiment, the FBG optical fiber sensor response signal obtained by the simulated impact loading specifically includes a time series of center wavelength offset values ​​of multiple FBG optical fiber sensors in the corresponding grid points.

[0069] A response threshold is set for each FBG fiber optic sensor corresponding to each grid point according to its central wave deviation value, and the central wave deviation value of each FBG fiber optic sensor after the actual impact is compared with the preset response threshold, so as to identify the FBG fiber optic sensor that generates an impact response, and construct an envelope line where the impact position is located, wherein constructing the envelope line where the impact position is located includes the following contents: determining the positions of the identified FBG fiber optic sensors that generate an impact response and the identified FBG fiber optic sensors that do not generate an impact response, obtaining the central grid points between any adjacent FBG fiber optic sensors that generate an impact response and the FBG fiber optic sensors that do not generate an impact response, and drawing the envelope line of the envelope impact position using the obtained central grid points as boundaries. Figure 5 and Figure 6 Schematic diagram of the impact point envelope drawn according to the above method at different impact positions in this embodiment.

[0070] See also Figure 8 , the calculation of the error outliers of each FBG optical fiber sensor in step 5 includes the following steps:

[0071] S401. Obtain the reference response signal corresponding to each grid point of the FBG optical fiber sensor, and pre-process the reference response signal and the actual impulse response signal to obtain a reference timing signal and three measured timing signals at three sampling time ends;

[0072] S402. Performing a standardization operation on a reference timing signal and the corresponding three measured timing signals;

[0073] S403. Calculate the error value between the standardized reference timing signal and the measured timing signal;

[0074] S404. Compare the calculated error value with the preset error threshold, and determine the outliers of each grid point in the envelope under the three sampling times.

[0075] Specifically, the preprocessing of the reference response signal in step S401 includes the following: taking the time point when the acquired reference response signal first reaches the response threshold as the starting point, taking several time points before and after, to obtain a reference timing signal; the reference timing signal includes the signal fluctuation caused by the complete impact load.

[0076] The preprocessing of the measured response signal in step S401 includes obtaining three segments of measured time series signals, and the specific obtaining method is as follows:

[0077] The first segment of the measured timing signal is obtained, that is, the time point when the measured response signal first reaches the response threshold is taken as the starting point, and a number of time points are taken before and after to obtain the first segment of the measured timing signal; the reference timing signal is in the same time period as the first measured timing signal. The second segment of the measured timing signal is obtained, that is, the sampling time period of the first end measured timing signal is advanced by one time point to obtain the second segment of the measured timing signal corresponding to the corresponding time period sensor. The third segment of the measured timing signal is obtained, that is, the sampling time period of the first end measured timing signal is delayed by one time point to obtain the second segment of the measured timing signal corresponding to the corresponding time period sensor.

[0078] Specifically, the formula for the standardization operation in step S402 of this embodiment is:

[0079] S s =(SS mean ) / S std ;

[0080] Where S represents the response signal, S mean represents the average value of the response signal, S std Represents the standard deviation of the response signal.

[0081] In practical applications, the errors of the measured response signal and the reference response signal of the same FBG optical fiber sensor in the envelope are compared in turn, and then the outliers of each grid point in the envelope are found by comparing the errors with the predetermined error threshold. It should be further explained that the calculation formula for the error value between the reference response signal after standardization and the measured impulse signal in step S403 is:

[0082] E (n,i) =S Ref.(n,i) -S Test (i);

[0083] In the formula, S Ref.(n,i) is the reference signal value of the sensor at the ith sampling point when the nth grid point in the envelope simulates impact, S Test(i) is the actual signal value of the sensor at the i-th sampling point.

[0084] like Figure 7 As shown in the figure, when the same sensor is at the same impact point, the error value of the two response signals is small, and when it is at different impact points, the error value of the response signal is large. Figure 7 It can be seen that if the error threshold is too large, there will be no outliers, and if the error threshold is too small, the actual position cannot be distinguished. Here, the accuracy of the error threshold needs to be ensured.

[0085] The calculation of the actual impact position by interpolation described in step six includes the following contents: arranging the outliers of each grid point in the multiple sampling time periods obtained in step five in ascending order; selecting the first n impact grid points in the ascending order, summing the outliers of the first n impact points, and determining the collection time period corresponding to the impact; arranging the outliers of each grid point in the collection time period corresponding to the impact in ascending order; obtaining the first m grid points in the ascending order of the outliers in the collection time period corresponding to the impact, and calculating the actual impact position of the obtained m grid points by interpolation; wherein, m≥3, n≥3.

[0086] In the carbon fiber wound shell impact load monitoring and positioning method of the present embodiment, when determining the actual impact position in step 6, the impact grid point selected is determined according to the data of the smallest several outlier groups in the outlier sequence obtained in the actual use scenario. When multiple data are similar, more outliers are obtained for difference calculation. The difference calculation formula in the interpolation calculation of the actual impact position in the present embodiment is:

[0087]

[0088] Where n represents the number of selected positions, O i represents the size of the outlier at the corresponding position, represents the x-coordinate of the grid point position, Represents the y-coordinate of the grid point location.

[0089] like Fig. 9 As shown, it is the final impact position determined when n=3 in this embodiment or embodiment 2.

[0090] The carbon fiber wrapped shell impact load monitoring and positioning method of this embodiment or the second embodiment is adopted. The FBG optical fiber sensor array is buried in the shell, and the data inside the shell can be monitored in real time. The shell is grid-divided with the FBG optical fiber sensor as the vertex. When the measured response signal enters, the following is performed: Fig.10 According to the calculation shown in the figure, the measured response signal and the reference response signal are first preprocessed and standardized, and then the error outlier is calculated using the error between the measured response signal and the reference response signal of the FBG optical fiber sensor, and finally the multiple minimum values ​​in the error outlier arrangement are used for interpolation calculation, that is, the impact position is calculated proportionally, which can realize accurate and rapid positioning of the actual impact position, and solve the problems in the prior art of frequent comprehensive non-destructive testing of the carbon fiber shell, time-consuming and labor-intensive, repeated narrowing of the impact position range, high positioning cost and inaccurate positioning.

[0091] It should be understood that the specific embodiments described above are only used to explain the present invention, and are not used to limit the present invention. Obvious changes or modifications derived from the spirit of the present invention are still within the protection scope of the present invention.

Claims

1. A method for monitoring and positioning impact load of a carbon fiber wound shell, characterized in that: The following steps are involved: Step 1: at least one FBG optical fiber sensor array is arranged for the carbon fiber wound shell, that is, before the carbon fiber wound shell is prepared, at least one FBG optical fiber sensor array that can evenly cover the carbon fiber wound shell is arranged; Step 2: During the preparation of the carbon fiber wound shell, the FBG optical fiber sensor array set in step 1 is buried inside the carbon fiber wound shell; Step 3: Obtaining a reference response signal of the FBG optical fiber sensor; dividing the carbon fiber-wound shell with the embedded shell FBG optical fiber sensor array completed in step 2 into a plurality of grids, performing simulated impact loading on each grid point on the grid one by one, and obtaining the FBG optical fiber sensor response signal as the reference response signal; Step 4: Set the response threshold of the FBG optical fiber sensor under the impact load, identify the FBG optical fiber sensor that responds under the impact load, and construct the envelope of the impact position; Step 5: Calculate the error outliers of each FBG fiber sensor within the envelope; Step 6: Based on the error outlier obtained in step 5, determine the actual impact position through interpolation calculation.

2. A carbon fiber wound shell impact load monitoring and positioning method according to claim 1, characterized in that: In step 3, the carbon fiber wrapped shell is divided into multiple grids including the following: Any minimum array in the FBG sensor array is used as the dividing boundary; The carbon fiber shell corresponding to the smallest array in the FBG sensor array is divided into a plurality of grids; the grids are square.

3. The method for monitoring and positioning impact load of a carbon fiber wound shell according to claim 1, characterized in that: The FBG optical fiber sensor response signal includes a time series of central wavelength offset values ​​of the FBG optical fiber sensor.

4. The method for monitoring and positioning impact load of a carbon fiber wound shell according to claim 1, characterized in that: The envelope of the impact position constructed in step 4 includes the following contents: The positions of the identified FBG optical fiber sensors that generate impulse responses and the identified FBG optical fiber sensors that do not generate impulse responses are determined; Acquire a central grid point between any adjacent FBG optical fiber sensor that generates an impulse response and any adjacent FBG optical fiber sensor that does not generate an impulse response; The envelope lines of the envelope impact positions are drawn using the obtained central grid points as boundaries.

5. The method for monitoring and positioning impact load of a carbon fiber wound shell according to claim 1, characterized in that: The calculation of the error outliers of each FBG optical fiber sensor in step 5 includes the following steps: S401. Obtain the reference response signal corresponding to each grid point of the FBG optical fiber sensor, and pre-process the reference response signal and the actual impulse response signal to obtain a reference timing signal and three measured timing signals of three adjacent sampling time periods; S402. Performing a standardization operation on a reference timing signal and the corresponding three measured timing signals; S403. Calculate the error value between the standardized reference timing signal and the measured timing signal; S404. Compare the calculated error value with the preset error threshold, and determine the outliers of each grid point in the envelope under three sampling times; The preprocessing of the reference response signal in step S401 includes the following: taking the time point when the acquired reference response signal first reaches the response threshold as the starting point, taking several time points before and after, to obtain a reference timing signal; the reference timing signal includes the signal fluctuation caused by the complete impact load.

6. A carbon fiber wound shell impact load monitoring and positioning method according to claim 4, characterized in that: The preprocessing of the measured response signal in step S401 includes the following steps: Acquire a first segment of measured timing signal, that is, take the time point when the measured response signal first reaches the response threshold as the starting point, and take several time points before and after to obtain the first segment of measured timing signal; the reference timing signal and the first measured timing signal are in the same time period; Acquire a second section of the measured time series signal, that is, advance the sampling time period of the first end measured time series signal by one time point to acquire the second section of the measured time series signal corresponding to the corresponding time period sensor; The third section of the measured timing signal is obtained, that is, the sampling time period of the first end measured timing signal is delayed by one time point to obtain the second section of the measured timing signal corresponding to the corresponding time period sensor.

7. The method for monitoring and positioning impact load of a carbon fiber wound shell according to claim 4, characterized in that: The formula for the standardization operation in step S402 is: S s =(S-S mean ) / S std ; Where S represents the response signal, S mean represents the average value of the response signal, S std Represents the standard deviation of the response signal.

8. The method for monitoring and positioning impact load of a carbon fiber wound shell according to claim 4, characterized in that: The calculation formula for the error value between the reference response signal after normalization and the measured impact signal in step S403 is: E (n,1) =S Ref.(n,1) -S Test(i) ; In the formula, S Ref.(n,1) is the reference signal value of the sensor at the ith sampling point when the nth grid point in the envelope simulates impact, S Test(i) is the actual signal value of the sensor at the i-th sampling point.

9. The method for monitoring and positioning the impact load of a carbon fiber wound shell according to claim 4, characterized in that: The calculation of the actual impact position by interpolation described in step 6 includes the following: Arrange the outliers of each grid point in the multiple sampling time periods obtained in step 5 in ascending order; Select the first n impact grid points in the ascending order, sum the outliers of the first n impact points, and determine the collection time period corresponding to the impact; Arrange the outliers of each grid point in the collection time period corresponding to the impact in ascending order; obtain the first m grid points in the ascending order of the outliers in the collection time period corresponding to the impact, and use interpolation to calculate the actual impact position for the obtained m grid points; where m≥3, n≥3.

10. The method for monitoring and positioning impact load of a carbon fiber wound shell according to claim 5, characterized in that: The interpolation calculation formula for the difference in the actual impact position in step 6 is: Where n represents the number of selected positions, O i represents the size of the outlier at the corresponding position, represents the x-coordinate of the grid point position, Represents the y-coordinate of the grid point location.

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