Cable accessory assembly quality detection method based on time domain transformation and related equipment

Abstract

The embodiment of the invention discloses a cable accessory assembly quality detection method based on time domain transformation and related equipment, and relates to the technical field of cable quality detection, time-frequency domain transformation is carried out on electromagnetic wave reflection signals to obtain a time-frequency spectrum matrix of each electromagnetic wave reflection signal, time and frequency can be fused through time domain transformation, and the time-frequency spectrum matrix of each electromagnetic wave reflection signal is obtained. The time-frequency spectrum matrix has time dimension information, and the parabolic interpolation can break through the sampling interval limitation, so that the appearance time of the reflectivity peak point obtained by searching the peak point in the time-frequency spectrum matrix and utilizing the parabolic interpolation is more accurate; whether the assembly quality of the to-be-detected cable accessory reaches the standard or not is judged by combining the electromagnetic wave reflectivity and the occurrence time, misjudgment of a single parameter is avoided, and the accuracy of an assembly quality detection result is further improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cable quality detection, and in particular to a cable accessory assembly quality detection method based on time domain transformation and related equipment. BACKGROUND

[0002] In the cable accessory assembly quality detection, the traditional method relies on single time domain or frequency domain analysis, which has significant defects: the time domain reflection method locates defects through the amplitude and time delay of the reflected signal, but is easily disturbed by noise, resulting in large time positioning error of the peak value of the small defect, affecting the assembly quality detection result, and the frequency domain reflection method can reflect the change of material characteristics, but lacks time dimension information, and it is difficult to obtain accurate assembly quality detection result. SUMMARY

[0003] Therefore, the present application provides a cable accessory assembly quality detection method based on time domain transformation and related equipment.

[0004] The specific technical scheme of the first embodiment of the present application is: a cable accessory assembly quality detection method based on time domain transformation, the method comprising: applying an electromagnetic wave excitation signal to different positions of a cable accessory to be detected for microwave scanning, and obtaining electromagnetic wave reflection signals at different positions; obtaining first electromagnetic wave reflectivity at different positions according to the electromagnetic wave excitation signal and the electromagnetic wave reflection signal; performing time-frequency domain transformation on the electromagnetic wave reflection signal to obtain a time-frequency spectrum matrix of each electromagnetic wave reflection signal; performing peak value search in all the time-frequency spectrum matrices to obtain a plurality of reflectivity peak points; performing parabolic interpolation on the reflectivity peak points to obtain a first occurrence time of each reflectivity peak point; and judging whether the assembly quality of the cable accessory to be detected meets the standard according to the first electromagnetic wave reflectivity and the first occurrence time.

[0005] Preferably, the time-frequency spectrum matrix is obtained by the following formula:

[0006] wherein, is the time-frequency spectrum matrix, is the amplitude of the first electromagnetic wave reflectivity, is the time for obtaining the electromagnetic wave reflection signal, is the frequency value of the electromagnetic wave excitation signal, is a Gaussian window function with window width varying with frequency, is a Fourier kernel function.

[0007] Preferably, the step of determining whether the assembly quality of the cable accessory to be tested meets the standard based on the first electromagnetic wave reflectivity and the first occurrence time includes: constructing a first curve of the change of the first electromagnetic wave reflectivity and the reflection position, and constructing a second curve of the change of the first occurrence time and the reflection position; and determining whether the assembly quality of the cable accessory to be tested meets the standard based on the first curve and the second curve.

[0008] Preferably, determining whether the assembly quality of the cable accessory to be tested meets the standard based on the first curve and the second curve includes: obtaining a third curve showing the change in the second electromagnetic wave reflectivity and the reflection position of a standard cable accessory, and a fourth curve showing the change in the second occurrence time of the peak value of the second electromagnetic wave reflectivity and the reflection position; the standard cable accessory is a cable accessory with compliant assembly quality; and determining whether the assembly quality of the cable accessory to be tested meets the standard based on the first curve, the second curve, the third curve, and the fourth curve.

[0009] Preferably, the step of determining whether the assembly quality of the cable accessory to be tested meets the standard based on the first curve, the second curve, the third curve, and the fourth curve includes: obtaining an assembly quality evaluation index of the cable accessory to be tested based on the first curve, the second curve, the third curve, and the fourth curve; the assembly quality evaluation index is used to characterize the probability that the assembly quality of the cable accessory to be tested meets the standard; and determining whether the assembly quality of the cable accessory to be tested meets the standard based on the assembly quality evaluation index and a preset threshold.

[0010] Preferably, the assembly quality evaluation index is obtained using the following formula:

[0011] in, The assembly quality evaluation index is referred to here. The starting point for electromagnetic wave reflection of the cable accessory to be tested. The endpoint of electromagnetic wave reflection. For the first curve The first electromagnetic wave reflectivity of the point For the third curve The second electromagnetic wave reflectivity of the point For the second curve i The first time of occurrence, The fourth curve i The second occurrence time, This represents the total number of times the first occurrence occurs. and For the preset weights, where, .

[0012] Preferably, the step of judging whether the assembly quality of the cable accessory to be detected meets a standard according to the assembly quality evaluation index and a preset threshold comprises: comparing the assembly quality evaluation index with the preset threshold; if the assembly quality evaluation index is greater than the preset threshold, the assembly quality of the cable accessory to be detected does not meet the standard; and if the assembly quality evaluation index is less than or equal to the preset threshold, the assembly quality of the cable accessory to be detected meets the standard.

[0013] The second embodiment of the present application provides a cable accessory assembly quality detection system based on time domain transformation, which comprises a reflected signal acquisition module, a reflectivity acquisition module, a transformation module, a search module, a peak time determination module and a detection module. The reflected signal acquisition module is configured to perform microwave scanning on different positions of a cable accessory to be detected by applying electromagnetic wave excitation signals to the different positions, and to acquire electromagnetic wave reflected signals of the different positions. The reflectivity acquisition module is configured to acquire first electromagnetic wave reflectivities of the different positions according to the electromagnetic wave excitation signals and the electromagnetic wave reflected signals. The transformation module is configured to perform time-frequency domain transformation on the electromagnetic wave reflected signals to obtain time-frequency spectrum matrices of the electromagnetic wave reflected signals. The search module is configured to perform peak value search in all the time-frequency spectrum matrices to obtain a plurality of reflectivity peak points. The peak time determination module is configured to perform parabolic interpolation on the reflectivity peak points to obtain first occurrence times of the reflectivity peak points. The detection module is configured to judge whether the assembly quality of the cable accessory to be detected meets a standard according to the first electromagnetic wave reflectivities and the first occurrence times.

[0014] The third embodiment of the present application provides a cable accessory assembly quality detection device based on time domain transformation, which comprises a memory and a processor. The memory stores a computer program. When the computer program is executed by the processor, the processor performs the steps of the method according to any one of the first embodiments of the present application.

[0015] The fourth embodiment of the present application provides a computer readable storage medium, which stores a computer program. When the computer program is executed by a processor, the processor performs the steps of the method according to any one of the first embodiments of the present application.

[0016] The embodiments of the present application have the following beneficial effects: The application obtains the time-frequency spectrum matrix of each electromagnetic wave reflection signal by performing time-frequency domain transformation on the electromagnetic wave reflection signal, time domain transformation can fuse time and frequency, so that the time-frequency spectrum matrix has time dimension information, and parabolic interpolation can break through the sampling interval limit, so that the occurrence time of the reflectivity peak point obtained by searching for the peak point in the time-frequency spectrum matrix and using parabolic interpolation is more accurate, and whether the assembly quality of the cable accessory to be detected meets the standard is judged by combining the electromagnetic wave reflectivity and the occurrence time, single parameter misjudgment is avoided, and the accuracy of the assembly quality detection result is further improved. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0018] Figure 1 The step flow chart of the cable accessory assembly quality detection method based on time domain transformation; Figure 2 The first curve and the third curve are schematic diagrams; Figure 3 The second curve and the fourth curve are schematic diagrams; Figure 4 The structure schematic diagram of the cable accessory assembly quality detection system based on time domain transformation; Figure 5 The internal structure diagram of the computer equipment; Among them, 201, reflection signal acquisition module; 202, reflectivity acquisition module; 203, transformation module; 204, search module; 205, peak time determination module; 206, detection module. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0020] The terms "first", "second", and the like in the description and in the claims of the present application and in the accompanying drawings are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. Moreover, the terms "comprising", "having", "including", and the like, when used in the present specification and in the accompanying claims are specifically intended to convey "including, but not limited to". For example, a process, method, object, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements but can include other steps or elements not expressly listed or inherent to such process, method, object, or apparatus.

[0021] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase "in an embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. It is expressly understood that any of the embodiments described herein can be incorporated in to other embodiments.

[0022] Reference is made to Figure 1 A flow chart of a method for detecting the assembly quality of a cable accessory based on time domain transformation is provided in the first embodiment of the application. The method can quickly and accurately determine whether the assembly quality of a cable accessory meets the standard. The method comprises the following steps: Step 101: Microwave scanning is performed on different positions of a cable accessory to be detected by applying an electromagnetic wave excitation signal, and electromagnetic wave reflection signals at different positions are obtained. Step 102: First electromagnetic wave reflectivity at different positions is obtained according to the electromagnetic wave excitation signal and the electromagnetic wave reflection signals. Step 103: Time-frequency domain transformation is performed on the electromagnetic wave reflection signals to obtain a time-frequency spectrum matrix of each electromagnetic wave reflection signal. Step 104: Peak value searching is performed in all the time-frequency spectrum matrices to obtain a plurality of reflectivity peak points. Step 105: Parabolic interpolation is performed on the reflectivity peak points to obtain a first occurrence time of each reflectivity peak point. Step 106: Whether the assembly quality of the cable accessory to be detected meets the standard is determined according to the first electromagnetic wave reflectivity and the first occurrence time.

[0023] The microwave scanning technology is used to apply electromagnetic wave excitation signals to different positions of the cable accessory to be detected, and electromagnetic wave reflection signals of the positions are obtained. According to the applied electromagnetic wave excitation signals and the obtained electromagnetic wave reflection signals, first electromagnetic wave reflectivities of the different positions are calculated. The electromagnetic wave reflectivity can directly reflect the reflection ability of the cable accessory to the electromagnetic wave, and is one of important parameters for evaluating the assembly quality of the cable accessory. Time-frequency domain transformation is performed on the obtained electromagnetic wave reflection signals to obtain time-frequency spectrum matrices of each electromagnetic wave reflection signal. The time-frequency spectrum matrices can display the characteristics of the signals from two dimensions of time and frequency, and provide more abundant information for subsequent analysis. Peak value searching is performed in all the time-frequency spectrum matrices to find a plurality of reflectivity peak points. The peak points often correspond to some key structures or defect positions in the cable accessory. In order to more accurately determine the time of the peak value, parabolic interpolation is performed on the reflectivity peak points to obtain first occurrence times of each reflectivity peak point. The first electromagnetic wave reflectivity and the first occurrence time are combined to judge the assembly quality of the cable accessory to be detected.

[0024] Specifically, after the microwave scanning of different positions of the cable accessory to be detected is completed and all the time-frequency spectrum matrices are obtained, peak value searching is first performed in the matrices to obtain a plurality of reflectivity peak points. The peak points contain key information of electromagnetic characteristics of the cable accessory, and are crucial for subsequent assembly quality detection. After the reflectivity peak points are obtained, parabolic interpolation operation is required to more accurately determine the occurrence time of the peak points. The parabolic interpolation is a numerical analysis method based on quadratic function fitting. Specifically, for each reflectivity peak point, a plurality of data points in a certain range near the peak point are selected. Usually, a plurality of time-frequency spectrum matrix data points adjacent to the left and right of the peak point are selected. The data points are closely related to the peak point in time and reflectivity value. Taking three selected data points as an example, suppose that time values of the three data points are t1, t2 and t3, and corresponding reflectivity values are r1, r2 and r3. A unique parabolic equation r = at 2 +bt+c can be determined by the three points. By using the coordinates of the three points, an equation group can be constructed, and the values of the coefficients a, b and c are obtained by solving the equation group. The abscissa of the vertex of the parabola is the more accurate occurrence time of the reflectivity peak point, that is, the first occurrence time.

[0025] The method in this embodiment obtains the time-frequency spectrum matrix of each electromagnetic wave reflection signal by performing time-frequency domain transformation on the electromagnetic wave reflection signal. Time-domain transformation can fuse time and frequency, so that the time-frequency spectrum matrix has time dimension information. Parabolic interpolation can break through the sampling interval limitation. Therefore, the occurrence time of the peak point of reflectivity obtained by searching for the peak point in the time-frequency spectrum matrix and using parabolic interpolation is more accurate. By combining the electromagnetic wave reflectivity and the occurrence time, the assembly quality of the cable accessory under test is judged to determine whether it meets the standard, avoiding misjudgment by a single parameter and further improving the accuracy of the assembly quality detection results.

[0026] In a specific embodiment, the time-frequency spectrum matrix is ​​obtained using the following formula:

[0027] in, The time-frequency spectrum matrix is... The amplitude of the first electromagnetic wave reflectivity. To obtain the time of the electromagnetic wave reflection signal, The frequency value of the electromagnetic wave excitation signal. Let Gaussian window function be used, where the window width varies with frequency. This is the Fourier kernel function.

[0028] Specifically, the time-spectrum matrix formula combines the first electromagnetic wave reflectivity with Gaussian window functions and Fourier kernel functions through integral operations. The Gaussian window function can adaptively weight the reflected electromagnetic wave signal based on the characteristics of the window width changing with frequency, effectively reducing the spectral leakage problem caused by signal truncation. This makes the signal features extracted from the time-spectrum matrix more accurate and can more realistically reflect the electromagnetic characteristics of different locations of cable accessories. At the same time, the time-spectrum matrix formula comprehensively analyzes the signal from both time and frequency dimensions, not only obtaining the energy distribution of the signal at each frequency component, but also clarifying the time information of the occurrence of different frequency components.

[0029] In summary, compared to existing time-frequency conversion methods, the Gaussian window function enables localized signal analysis in the time-frequency plane. This means that signal characteristics can be observed within a specific time and frequency range. The window width varies with frequency, resulting in better time resolution in the high-frequency range and better frequency resolution in the low-frequency range. This is achieved by using the amplitude of the first electromagnetic wave reflectivity. Calculating the frequency spectrum matrix allows analysis of the reflection characteristics of electromagnetic waves when they encounter different media, thereby obtaining information about materials or structures and improving the accuracy of assembly quality.

[0030] In a specific embodiment, the step of determining whether the assembly quality of the cable accessory to be tested meets the standard based on the first electromagnetic wave reflectivity and the first occurrence time includes: constructing a first curve of the change of the first electromagnetic wave reflectivity and the reflection position, and constructing a second curve of the change of the first occurrence time and the reflection position; and determining whether the assembly quality of the cable accessory to be tested meets the standard based on the first curve and the second curve.

[0031] Specifically, using the change in reflection position as the abscissa, a first curve is constructed to represent the change in electromagnetic wave reflectivity versus reflection position, and a second curve is constructed to represent the change in the first occurrence time versus reflection position. The first curve clearly shows the change in the electromagnetic wave reflection capability of the cable accessory at different locations. If the internal structure of the cable accessory is uniform and the assembly quality is good, the first curve should show a relatively stable or regular trend; conversely, if there are defects or assembly quality problems, the first curve may show abnormal fluctuations. The second curve reflects the change in the occurrence time of the reflectivity peak point with the reflection position. For cable accessories with qualified assembly quality, the second curve should also have a certain regularity. When the cable accessory has problems such as internal damage or uneven materials, this curve may deviate from the normal pattern.

[0032] In a specific embodiment, determining whether the assembly quality of the cable accessory to be tested meets the standard based on the first curve and the second curve includes: obtaining a third curve showing the change in the second electromagnetic wave reflectivity and the reflection position of a standard cable accessory, and a fourth curve showing the change in the second occurrence time of the peak value of the second electromagnetic wave reflectivity and the reflection position; the standard cable accessory is a cable accessory with compliant assembly quality; determining whether the assembly quality of the cable accessory to be tested meets the standard based on the first curve, the second curve, the third curve, and the fourth curve.

[0033] Specifically, the third curve showing the change in the second electromagnetic wave reflectivity of a standard cable accessory relative to the reflection position, and the fourth curve showing the change in the peak time of the second electromagnetic wave reflectivity relative to the reflection position, are obtained. Since the standard cable accessory is a product with compliant assembly quality, its corresponding third and fourth curves represent the electromagnetic characteristic variation law of the cable accessory under ideal assembly quality conditions. The third curve reflects the normal change in electromagnetic wave reflectivity of the standard cable accessory at different reflection positions, while the fourth curve shows a reasonable pattern of peak time occurrence with reflection position variation. When judging the assembly quality of the cable accessory to be tested, the first and third curves of the cable accessory to be tested are compared. The differences between the two curves in terms of trend and amplitude are observed. If the difference is within a preset reasonable range, it indicates that the electromagnetic wave reflectivity characteristics of the cable accessory to be tested are relatively close to those of the standard cable accessory. Simultaneously, the second and fourth curves are compared to analyze whether the pattern of peak time occurrence with reflection position variation is consistent. Based on the comparison results of these two sets of curves, if the first curve and the third curve, and the second curve and the fourth curve, are highly consistent, then it can be determined that the assembly quality of the cable accessory under test meets the standards. If there are significant differences, it indicates that the cable accessory under test may have assembly quality problems, such as internal structural defects or uneven materials, which require further investigation and analysis.

[0034] In a specific embodiment, determining whether the assembly quality of the cable accessory to be tested meets the standard based on the first curve, the second curve, the third curve, and the fourth curve includes: obtaining an assembly quality evaluation index for the cable accessory to be tested based on the first curve, the second curve, the third curve, and the fourth curve; the assembly quality evaluation index is used to characterize the probability that the assembly quality of the cable accessory to be tested meets the standard; and determining whether the assembly quality of the cable accessory to be tested meets the standard based on the assembly quality evaluation index and a preset threshold. Specifically, by constructing the first curve and the second curve of the cable accessory to be tested, and the third curve and the fourth curve of the standard cable accessory, and obtaining the assembly quality evaluation index based on the first curve, the originally abstract curve comparison is transformed into a specific quantitative index. This index can more accurately reflect the difference between the cable accessory to be tested and the standard cable accessory, reduce the subjectivity of human judgment, and make the judgment of assembly quality compliance more objective and accurate.

[0035] In a specific embodiment, the assembly quality evaluation index is obtained using the following formula:

[0036] in, The assembly quality evaluation index is referred to here. The starting point for electromagnetic wave reflection of the cable accessory to be tested. The endpoint of electromagnetic wave reflection. For the first curve The first electromagnetic wave reflectivity of the point For the third curve The second electromagnetic wave reflectivity of the point For the second curve i The first time of occurrence, The fourth curve i The second occurrence time, This represents the total number of times the first occurrence occurs. and For the preset weights, where, Specifically, by quantifying the differences in electromagnetic reflectivity between the first and third curves, and the differences in peak occurrence time between the second and fourth curves, subtle differences between the cable accessories under inspection and the standard can be captured more accurately. This improves the accuracy of assembly quality assessment and avoids errors that may arise from relying on a single factor. Furthermore, it considers not only information from individual locations but also integrates the peak occurrence time differences from multiple locations through summation. This multi-dimensional, multi-location assessment method allows the results to more comprehensively reflect the overall assembly quality of the cable accessories.

[0037] For details, please refer to Figure 2 and Figure 3 .in, Figure 2 The reflectivity (reflection coefficient) curve for the moisture-affected mid-terminal head is the first curve. Figure 2 The reflectance (reflectance coefficient) curve for a dry terminal head is the third curve. The first and third curves have the same number of sampling points. Figure 3 The peak occurrence time of the moisture defect in the middle terminal head is shown in the second curve. Figure 3 The peak occurrence time of the defect-free terminal head is shown on the fourth curve. The second and fourth curves have the same number of sampling points. The reflectance corresponding to the first curve is used as the [data point index] in the order of the number of sampling points for the first and third curves, and in the order of the number of sampling points for the second and fourth curves. The reflectance corresponding to the third curve is taken as The peak occurrence time in the second curve is taken as... The peak time in the fourth curve is taken as... Substitute into the following order Obtained from the calculation formula The value will By comparing the value with a preset threshold, it can be determined whether the assembly quality meets the standard. The number of sampling points is based on the transmission bandwidth and the cable accessories to be tested (the cable coupling distance needs to be considered); each scanning point represents a distance length of c / (2B), where c represents the speed of light and B represents the bandwidth (terminal frequency - starting frequency).

[0038] In a specific embodiment, determining whether the assembly quality of the cable accessory to be tested meets the standard based on the assembly quality evaluation index and the preset threshold includes: comparing the assembly quality evaluation index and the preset threshold; if the assembly quality evaluation index is greater than the preset threshold, the assembly quality of the cable accessory to be tested does not meet the standard; if the assembly quality evaluation index is less than or equal to the preset threshold, the assembly quality of the cable accessory to be tested meets the standard.

[0039] Specifically, the preset threshold can be set according to the actual situation. The assembly quality evaluation index is combined with the preset threshold to judge whether the assembly quality meets the standard. This not only obtains accurate assembly quality inspection results, but also further refines the assembly quality classification. For example, different assembly quality evaluation indices in different ranges correspond to different assembly quality classifications.

[0040] In a specific embodiment, the second embodiment of this application provides a schematic diagram of a cable accessory assembly quality inspection system based on time-domain transformation. The system includes: a reflection signal acquisition module 201, a reflectivity acquisition module 202, a transformation module 203, a search module 204, a peak time determination module 205, and a detection module 206. The reflection signal acquisition module 201 is used to apply electromagnetic wave excitation signals to different positions of the cable accessory to be inspected and perform microwave scanning to acquire electromagnetic wave reflection signals at different positions. The reflectivity acquisition module 202 is used to obtain the electromagnetic wave reflection signals based on the electromagnetic wave excitation signal and the electromagnetic wave reflection signals. The first electromagnetic wave reflectivity at different locations is obtained; the transformation module 203 is used to perform time-frequency domain transformation on the electromagnetic wave reflected signal to obtain the time-frequency spectrum matrix of each electromagnetic wave reflected signal; the search module 204 is used to perform peak search in all the time-frequency spectrum matrices to obtain multiple reflectivity peak points; the peak time determination module 205 is used to perform parabolic interpolation on the reflectivity peak points to obtain the first occurrence time of each reflectivity peak point; the detection module 206 is used to determine whether the assembly quality of the cable accessory to be tested meets the standard based on the first electromagnetic wave reflectivity and the first occurrence time.

[0041] In this embodiment, the system obtains the time-frequency spectrum matrix of each electromagnetic wave reflection signal by performing time-frequency domain transformation on the electromagnetic wave reflection signal. Time-domain transformation can fuse time and frequency, so that the time-frequency spectrum matrix has time dimension information. Parabolic interpolation can break through the sampling interval limitation. Therefore, the occurrence time of the peak point of reflectivity obtained by searching for the peak point in the time-frequency spectrum matrix and using parabolic interpolation is more accurate. By combining the electromagnetic wave reflectivity and the occurrence time, the system judges whether the assembly quality of the cable accessory under test meets the standard, avoids misjudgment based on a single parameter, and further improves the accuracy of the assembly quality detection results.

[0042] In a specific embodiment, the third embodiment of this application provides a cable accessory assembly quality inspection device based on time-domain transformation, including a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the method described in any one of the first embodiments of this application. The device in this embodiment obtains the time-frequency spectrum matrix of each electromagnetic wave reflection signal by performing time-frequency domain transformation on the electromagnetic wave reflection signal. Time-domain transformation can fuse time and frequency, giving the time-frequency spectrum matrix time dimension information. Parabolic interpolation can overcome the sampling interval limitation, thus making the occurrence time of the peak point of reflectivity obtained by searching for peak points in the time-frequency spectrum matrix and using parabolic interpolation more accurate. By combining electromagnetic wave reflectivity and occurrence time, the assembly quality of the cable accessory under inspection is judged to be up to standard, avoiding misjudgment based on a single parameter and further improving the accuracy of the assembly quality inspection results.

[0043] In a specific embodiment, the fourth embodiment of this application provides a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the method as described in any one of the first embodiments of this application.

[0044] Figure 3 An internal structural diagram of a computer device in one embodiment is shown. This computer device can specifically be a terminal or a server. See also... Figure 3 The computer device includes a processor, memory, etc., connected via a system bus. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and may also store a computer program. When executed by the processor, this computer program causes the processor to implement the method described in this embodiment. The internal memory may also store a computer program, which, when executed by the processor, causes the processor to perform the method described in this embodiment. Those skilled in the art will understand that... Figure 3The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0045] The above embodiments merely illustrate several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

[0046] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for inspecting the assembly quality of cable accessories based on time-domain transformation, characterized in that, The method includes: Microwave scanning is performed by applying electromagnetic wave excitation signals to different locations of the cable accessories to be tested to obtain electromagnetic wave reflection signals at different locations; The first electromagnetic wave reflectivity at different locations is obtained based on the electromagnetic wave excitation signal and the electromagnetic wave reflection signal. The time-frequency domain transformation of the electromagnetic wave reflection signal is performed to obtain the time-frequency spectrum matrix of each electromagnetic wave reflection signal; Peak search is performed in the entire time-spectrum matrix to obtain multiple reflectivity peak points; Parabolic interpolation is performed on the reflectivity peak points to obtain the first occurrence time of each reflectivity peak point; The assembly quality of the cable accessory to be tested is determined based on the first electromagnetic wave reflectivity and the first occurrence time.

2. The cable accessory assembly quality inspection method based on time-domain transformation as described in claim 1, characterized in that, The time-frequency matrix is ​​obtained using the following formula: in, The time-frequency spectrum matrix is... The amplitude of the first electromagnetic wave reflectivity. To obtain the time of the electromagnetic wave reflection signal, The frequency value of the electromagnetic wave excitation signal. Let Gaussian window function be used, where the window width varies with frequency. This is the Fourier kernel function.

3. The cable accessory assembly quality inspection method based on time-domain transformation as described in claim 1, characterized in that, The step of determining whether the assembly quality of the cable accessory to be tested meets the standard based on the first electromagnetic wave reflectivity and the first occurrence time includes: Construct a first curve showing the change between the reflectivity of the first electromagnetic wave and the reflection position, and construct a second curve showing the change between the first occurrence time and the reflection position; The assembly quality of the cable accessory to be tested is determined based on the first curve and the second curve.

4. The cable accessory assembly quality inspection method based on time-domain transformation as described in claim 3, characterized in that, Determining whether the assembly quality of the cable accessory to be tested meets the standards based on the first curve and the second curve includes: Obtain a third curve showing the change in the second electromagnetic wave reflectivity and the reflection position of a standard cable accessory, and a fourth curve showing the change in the second occurrence time of the peak value of the second electromagnetic wave reflectivity and the reflection position; the standard cable accessory is a cable accessory whose assembly quality meets the standards. The assembly quality of the cable accessory to be tested is determined based on the first curve, the second curve, the third curve, and the fourth curve.

5. The cable accessory assembly quality inspection method based on time-domain transformation as described in claim 4, characterized in that, The step of determining whether the assembly quality of the cable accessory to be tested meets the standard based on the first curve, the second curve, the third curve, and the fourth curve includes: The assembly quality evaluation index of the cable accessory to be tested is obtained based on the first curve, the second curve, the third curve, and the fourth curve; the assembly quality evaluation index is used to characterize the probability that the assembly quality of the cable accessory to be tested meets the standard. The assembly quality of the cable accessory to be tested is determined based on the assembly quality evaluation index and the preset threshold.

6. The cable accessory assembly quality inspection method based on time-domain transformation as described in claim 5, characterized in that, The assembly quality evaluation index is obtained using the following formula: in, The assembly quality evaluation index is referred to here. The starting point for electromagnetic wave reflection of the cable accessory to be tested. The endpoint of electromagnetic wave reflection. For the first curve The first electromagnetic wave reflectivity of the point For the third curve The second electromagnetic wave reflectivity of the point For the second curve i The first time of occurrence, The fourth curve i The second occurrence time, This represents the total number of times the first occurrence occurs. and For the preset weights, where, .

7. The cable accessory assembly quality inspection method based on time-domain transformation as described in claim 5, characterized in that, The step of determining whether the assembly quality of the cable accessory to be tested meets the standard based on the assembly quality evaluation index and the preset threshold includes: The assembly quality evaluation indicators are compared with preset thresholds; If the assembly quality evaluation index is greater than the preset threshold, then the assembly quality of the cable accessory to be tested is substandard. If the assembly quality evaluation index is less than or equal to the preset threshold, then the assembly quality of the cable accessory to be tested meets the standard.

8. A cable accessory assembly quality inspection system based on time-domain transformation, characterized in that, The system includes: a reflected signal acquisition module, a reflectivity acquisition module, a transformation module, a search module, a peak time determination module, and a detection module; The reflected signal acquisition module is used to apply electromagnetic wave excitation signals to different positions of the cable accessory to be tested and perform microwave scanning to acquire electromagnetic wave reflected signals at different positions. The reflectivity acquisition module is used to acquire the first electromagnetic wave reflectivity at different locations based on the electromagnetic wave excitation signal and the electromagnetic wave reflection signal. The transformation module is used to perform time-frequency domain transformation on the electromagnetic wave reflection signal to obtain the time-frequency spectrum matrix of each electromagnetic wave reflection signal; The search module is used to perform peak search in the entire time-spectrum matrix to obtain multiple reflectivity peak points; The peak time determination module is used to perform parabolic interpolation on the reflectivity peak points to obtain the first occurrence time of each reflectivity peak point; The detection module is used to determine whether the assembly quality of the cable accessory to be tested meets the standard based on the first electromagnetic wave reflectivity and the first occurrence time.

9. A cable accessory assembly quality inspection device based on time-domain transformation, comprising a memory and a processor, characterized in that, The memory stores a computer program that, when executed by the processor, causes the processor to perform the steps of the method as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it causes the processor to perform the steps of the method as described in any one of claims 1 to 7.

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