Aircraft fault maintenance management method, system and computer program product

Abstract

The present invention discloses an aircraft fault maintenance management method, system and computer program product. The present invention uses the head-end reflection coefficient spectrum of an aviation cable and combines it with the fault detection distance function of the aviation cable to construct a fault diagnosis function. Then, the polarity and position of the extreme point of the function waveform diagram can be used to determine the fault position and impedance state of the aviation cable. Finally, the impedance state of the aviation cable can be used to obtain its fault type. Thus, compared with the traditional technology, the present invention does not need to perform fast Fourier transform or inverse transform on the reflection coefficient spectrum, is not affected by the number of test points, and does not need to rewrite the reflection coefficient spectrum data. Therefore, the accuracy of aviation cable fault detection is improved, so that it is very suitable for large-scale application and promotion.

Description

Technical Field

[0001] The present invention belongs to the technical field of aircraft fault detection, and in particular relates to an aircraft fault maintenance management method, system and computer program product. Background Art

[0002] Aircraft cables are widely distributed in every corner of the aircraft. They are the hub connecting various devices on the aircraft and an important component for providing power and transmitting signals for the aircraft. Due to the special structural characteristics of the aircraft, it has high requirements on the volume and weight of the cables. Therefore, aircraft cables usually use ordinary aviation cables with smaller diameters and thinner insulation layers. However, during the flight of the aircraft, due to long-term vibration, corrosion, aging and other factors, open circuit and short circuit faults may occur in the aircraft cables, posing a great threat to flight safety. Therefore, the research on fault detection and positioning technology of aircraft cables is becoming more and more urgent.

[0003] In practical applications, aircraft cable fault detection mostly uses the frequency domain reflection method, in which the frequency domain reflection method transmits a set of sweep frequency signals at the head end of the cable, and then detects the head end impedance spectrum or reflection coefficient spectrum of the aircraft cable under a wide frequency, thereby performing aircraft cable fault detection based on the head end impedance spectrum or reflection coefficient spectrum.

[0004] At present, most people use the fast Fourier transform algorithm to analyze the reflection coefficient spectrum, or use the inverse fast Fourier transform algorithm to transform the reflection coefficient spectrum into the time domain characteristic waveform of the defect, and then perform aircraft cable fault detection based on this; however, the above-mentioned existing technologies have the following deficiencies: the fast Fourier transform algorithm has the disadvantage that the number of points before and after the transformation is constant, so the fault location of this method will be limited by the number of test points, thereby reducing the accuracy of fault location; and the inverse fast Fourier transform algorithm needs to use interpolation and random assignment to rewrite the reflection coefficient spectrum data, which will affect the accuracy of fault detection; therefore, based on the above-mentioned deficiencies, how to provide an aircraft fault maintenance management method with high accuracy of aircraft cable fault detection has become a problem to be solved urgently. Summary of the invention

[0005] The purpose of the present invention is to provide an aircraft fault maintenance management method, system and computer program product to solve the problem of low accuracy of aircraft cable fault detection in the prior art.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] In a first aspect, a method for managing aircraft failure maintenance is provided, comprising:

[0008] Transmitting sweep frequency signals of different test frequencies to the aviation cable on the target aircraft, so as to determine the head-end reflection coefficient spectrum of the aviation cable based on each sweep frequency signal;

[0009] Constructing a fault detection distance function of the aviation cable, and generating a fault diagnosis function of the aviation cable based on the head end reflection coefficient spectrum and the fault detection distance function;

[0010] According to the fault diagnosis function of the aviation cable, a fault diagnosis waveform diagram of the aviation cable is generated, wherein the horizontal axis of the fault diagnosis waveform diagram is the fault detection distance, and the vertical axis is the cable fault characteristic value;

[0011] Determine the cable fault characteristic extreme value point from the fault diagnosis waveform diagram, determine the impedance state of the aviation cable according to the polarity of the cable fault characteristic extreme value point, and determine the fault position of the aviation cable according to the fault detection distance corresponding to the cable fault characteristic extreme value point;

[0012] Based on the impedance state, the fault type of the aviation cable is obtained, and the fault location and fault type of the aviation cable are recorded in the fault log and sent to the maintenance terminal, so as to complete the fault maintenance management of the target aircraft after sending.

[0013] Based on the above disclosed content, the present invention constructs a fault detection distance function of the aviation cable after determining the head-end reflection coefficient spectrum of the aviation cable by using sweeping signals of different test frequencies; then, in combination with the aforementioned head-end reflection coefficient spectrum, a fault diagnosis function of the aviation cable is established; then, using the fault diagnosis function, a fault diagnosis waveform of the aviation cable is generated with the horizontal axis being the fault detection distance and the vertical axis being the fault detection characteristic value; then, the polarity of the extreme point in the fault diagnosis waveform and the corresponding fault detection distance can be used to determine the impedance state and fault location of the aviation cable; finally, according to the impedance state of the aviation cable, the fault type of the aviation cable can be obtained.

[0014] Through the above design, the present invention directly uses the head-end reflection coefficient spectrum of the aviation cable and the fault detection distance function to construct a fault diagnosis function, and then, the polarity and position of the extreme points of the function waveform are used to determine the fault type and position of the aviation cable; thus, compared with the traditional technology, the present invention does not need to perform fast Fourier transform or inverse transform on the reflection coefficient spectrum, is not affected by the number of test points, and does not need to rewrite the reflection coefficient spectrum data, thereby improving the accuracy of fault detection, and is very suitable for large-scale application and promotion.

[0015] In a possible design, based on each frequency sweep signal, a reflection coefficient spectrum of the first end of the aviation cable is determined, including:

[0016] Acquiring cable parameters of the aviation cable, and calculating the characteristic impedance of the aviation cable based on the cable parameters;

[0017] Calculating reflection parameters of the aviation cable according to the characteristic impedance and the cable parameters;

[0018] The head-end reflection coefficient spectrum of the aviation cable is calculated according to the reflection parameter, the cable parameter and the test frequency of each frequency sweep signal.

[0019] In a possible design, the cable parameters include: the end load impedance of the aviation cable, the length of the aviation cable, and the cable wave speed, unit inductance, and unit capacitance of the aviation cable;

[0020] Based on the cable parameters, the characteristic impedance of the aviation cable is calculated, including:

[0021] Calculating a ratio of the unit inductance to the unit capacitance, and obtaining a square root of the ratio, so as to obtain a characteristic impedance of the aviation cable based on the square root;

[0022] The step of calculating the reflection parameters of the aviation cable according to the characteristic impedance and the cable parameters includes:

[0023] According to the end load impedance of the aviation cable and the characteristic impedance, and in accordance with the following formula (1), the reflection parameter of the aviation cable is calculated;

[0024] (1)

[0025] In the above formula (1), represents the reflection parameter of the aviation cable, represents the end load impedance of the aviation cable, represents the characteristic impedance;

[0026] Correspondingly, calculating the head-end reflection coefficient spectrum of the aviation cable according to the reflection parameter, the cable parameter and the test frequency of each sweep signal includes:

[0027] According to the following formula (2), the head end reflection coefficient spectrum is calculated;

[0028] (2)

[0029] In the above formula (2), represents the head-end reflection coefficient spectrum, represents the nth test frequency, Indicates the length of the aviation cable, is the signal transmission attenuation constant, represents the cable wave velocity of the aviation cable, represents the imaginary unit, where ,and Indicates the total number of test frequencies.

[0030] In a possible design, a fault detection distance function of the aviation cable is constructed, including:

[0031] Determining a maximum fault detection distance and a minimum fault detection distance according to the length of the aviation cable;

[0032] Calculating the number of fault detection distance sampling points based on the maximum fault detection distance and the minimum fault detection distance;

[0033] A fault detection distance function of the aviation cable is constructed according to the minimum fault detection distance and the number of fault detection distance sampling points.

[0034] In a possible design, the number of fault detection distance sampling points is calculated based on the maximum fault detection distance and the minimum fault detection distance, including:

[0035] According to the following formula (3), the number of sampling points of the fault detection distance is calculated;

[0036] (3)

[0037] In the above formula (3), represents the number of sampling points of the fault detection distance, represents the maximum fault detection distance, represents the minimum distance for fault detection, represents the fault detection interval distance, and Indicates the floor rounding operator;

[0038] Correspondingly, according to the minimum fault detection distance and the number of fault detection distance sampling points, a fault detection distance function of the aviation cable is constructed, which includes:

[0039] According to the following formula (4), the fault detection distance function is constructed;

[0040] (4)

[0041] In the above formula (4), represents the fault detection distance function, Indicates the sequence number of the fault detection distance sampling point, where: .

[0042] In one possible design, a fault diagnosis function of the aviation cable is generated based on the head-end reflection coefficient spectrum and the fault detection distance function, including:

[0043] Generating a fault detection distance and test frequency function according to the fault detection distance function and each test frequency;

[0044] Based on the head-end reflection coefficient spectrum, calculating the reflection coefficient mean value of the aviation cable;

[0045] The fault diagnosis function of the aviation cable is generated by using the head-end reflection coefficient spectrum, the reflection coefficient mean value, and the fault detection distance and test frequency function.

[0046] In one possible design, generating a fault detection distance and test frequency function according to the fault detection distance function and each test frequency includes:

[0047] According to the following formula (5), the fault detection distance and test frequency function is generated;

[0048] (5)

[0049] In the above formula (5), represents the function of the fault detection distance and the test frequency, represents the nth test frequency, represents the cable wave velocity of the aviation cable, represents the fault detection distance function, Indicates the sequence number of the fault detection distance sampling point, where: , ,and represents the total number of test frequencies, Indicates the number of fault detection distance sampling points;

[0050] Correspondingly, the fault diagnosis function of the aviation cable is generated by using the head-end reflection coefficient spectrum, the reflection coefficient mean value, and the fault detection distance and test frequency function, which includes:

[0051] According to the fault detection distance and test frequency function, determining a function mean of the fault detection distance and test frequency function at each fault detection distance;

[0052] Based on the head-end reflection coefficient spectrum, the reflection coefficient mean, the fault detection distance and test frequency function, and the function mean of the fault detection distance and test frequency function at each fault detection distance, and according to the following formula (6), a fault diagnosis function of the aviation cable is generated;

[0053] (6)

[0054] In the above formula (6), represents the fault diagnosis function, represents the head-end reflection coefficient spectrum, represents the mean value of the reflection coefficient, It represents the function of fault detection distance and test frequency. The function mean at the fault detection distance corresponding to the fault detection distance sampling point of Represents the real part operation.

[0055] In a possible design, the impedance state of the aviation cable is determined according to the polarity of the extreme value point of the cable fault characteristic, and the fault position of the aviation cable is determined according to the fault detection distance corresponding to the extreme value point of the cable fault characteristic, including:

[0056] Determining whether the polarity of the cable fault characteristic extreme point is positive;

[0057] If so, it is determined that the impedance state of the aviation cable is an impedance increasing state; otherwise, it is determined that the impedance state of the aviation cable is an impedance decreasing state;

[0058] The fault detection distance corresponding to the extreme value point of the cable fault characteristic is used as the distance between the fault point and the head end of the aviation cable, so as to determine the fault position of the aviation cable based on the distance between the fault point and the head end of the aviation cable;

[0059] Accordingly, based on the impedance state, the fault type of the aviation cable is obtained, which includes:

[0060] If the impedance state is an impedance increase state, it is determined that the fault type of the aviation cable is an open circuit fault; if the impedance state is an impedance decrease state, it is determined that the fault type of the aviation cable is a short circuit fault.

[0061] In a second aspect, an aircraft fault maintenance management system is provided, comprising:

[0062] A frequency sweeping unit, used for transmitting frequency sweeping signals of different test frequencies to the aviation cable on the target aircraft, so as to determine the head-end reflection coefficient spectrum of the aviation cable based on each frequency sweeping signal;

[0063] A function construction unit, used to construct a fault detection distance function of the aviation cable, and generate a fault diagnosis function of the aviation cable based on the head end reflection coefficient spectrum and the fault detection distance function;

[0064] A feature extraction unit, used to generate a fault diagnosis waveform diagram of the aviation cable according to the fault diagnosis function of the aviation cable, wherein the horizontal axis of the fault diagnosis waveform diagram is the fault detection distance, and the vertical axis is the cable fault characteristic value;

[0065] A fault diagnosis unit, configured to determine a cable fault characteristic extreme value point from the fault diagnosis waveform diagram, determine an impedance state of the aviation cable according to the polarity of the cable fault characteristic extreme value point, and determine a fault position of the aviation cable according to a fault detection distance corresponding to the cable fault characteristic extreme value point;

[0066] The fault diagnosis unit is also used to derive the fault type of the aviation cable based on the impedance state, and record the fault location and fault type of the aviation cable in a fault log, and send it to a maintenance terminal, so as to complete the fault maintenance management of the target aircraft after sending.

[0067] In a third aspect, an aircraft fault maintenance management device is provided. Taking the device as an electronic device as an example, the device includes a memory, a processor and a transceiver which are communicatively connected in sequence, wherein the memory is used to store computer programs, the transceiver is used to send and receive messages, and the processor is used to read the computer program to execute the aircraft fault maintenance management method as described in the first aspect or any possible design of the first aspect.

[0068] In a fourth aspect, a storage medium is provided, on which instructions are stored. When the instructions are executed on a computer, the aircraft fault maintenance management method as in the first aspect or any possible design of the first aspect is executed.

[0069] In a fifth aspect, a computer program product comprising instructions is provided, which, when executed on a computer, causes the computer to execute the aircraft fault maintenance management method as described in the first aspect or any possible design of the first aspect.

[0070] Beneficial effects:

[0071] (1) The present invention directly uses the head-end reflection coefficient spectrum of the aviation cable and the fault detection distance function to construct a fault diagnosis function, and then uses the polarity and position of the extreme point of the function waveform to determine the fault type and position of the aviation cable. Thus, compared with the traditional technology, the present invention does not need to perform fast Fourier transform or inverse transform on the reflection coefficient spectrum, is not affected by the number of test points, and does not need to rewrite the reflection coefficient spectrum data. Therefore, the accuracy of fault detection is improved, making it very suitable for large-scale application and promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1A schematic diagram of the steps of the aircraft fault maintenance management method provided by an embodiment of the present invention;

[0073] Figure 2 A schematic diagram of the structure of an aircraft fault maintenance management system provided by an embodiment of the present invention;

[0074] Figure 3 A schematic diagram of the structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0075] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the present invention will be briefly introduced below in combination with the drawings and the description of the embodiments or the prior art. Obviously, the following description of the structure of the drawings is only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention.

[0076] It should be understood that although the terms first, second, etc. may be used herein to describe various units, these units should not be limited by these terms. These terms are only used to distinguish one unit from another unit. For example, a first unit can be referred to as a second unit, and similarly, a second unit can be referred to as a first unit without departing from the scope of the exemplary embodiments of the present invention.

[0077] It should be understood that the term "and / or" that may appear in this article is merely a description of the association relationship between associated objects, indicating that three relationships may exist. For example, A and / or B can represent three situations: A exists alone, B exists alone, and A and B exist at the same time. The term " / and" that may appear in this article describes another type of association object relationship, indicating that two relationships may exist. For example, A / and B can represent two situations: A exists alone, and A and B exist alone. In addition, the character " / " that may appear in this article generally indicates that the previous and next associated objects are in an "or" relationship.

[0078] Example:

[0079] See also Figure 1As shown, the aircraft fault maintenance management method provided in this embodiment uses the head-end reflection coefficient spectrum of the aviation cable and combines it with the fault detection distance function of the aviation cable to construct a fault diagnosis function, and then, the polarity and position of the extreme points of the function waveform diagram can be used to determine the fault location and impedance state of the aviation cable; finally, the impedance state of the aviation cable can be used to obtain its fault type; thus, compared with the traditional technology, the present method does not need to perform fast Fourier transform or inverse transform on the reflection coefficient spectrum, is not affected by the number of test points, and does not need to rewrite the reflection coefficient spectrum data, thereby improving the accuracy of aviation cable fault detection, and is thus very suitable for large-scale application and promotion; among them, for example, the present method can be but not limited to running on the aircraft fault maintenance management end side, it can be understood that the aforementioned execution subject does not constitute a limitation on the embodiments of the present application, and accordingly, the operation steps of the present method can be but not limited to the following steps S1 to S5.

[0080] S1. Transmitting frequency sweep signals of different test frequencies to the aviation cable on the target aircraft, so as to determine the head-end reflection coefficient spectrum of the aviation cable based on each frequency sweep signal; in specific implementation, for example, but not limited to, sampling a number of frequencies in the frequency range of 5 Hz to 200 MHz as test frequencies, thereby connecting the conductor and the copper shielding layer of the aviation cable using a test fixture on the aircraft fault maintenance management end, so as to inject the frequency sweep signals of the different test frequencies into the aviation cable; wherein, for example, the aircraft fault maintenance management end may include, but not limited to, a reflection coefficient spectrum analyzer and a computer, and the reflection coefficient spectrum analyzer plays the function of injecting the frequency sweep signal.

[0081] In this way, after inputting sweep frequency signals of different test frequencies into the aviation cable, the head-end reflection coefficient spectrum of the aviation cable can be determined based on this, so that the fault diagnosis function of the aviation cable can be constructed based on the head-end reflection coefficient spectrum, thereby realizing the fault identification of the aviation cable; among which, for example, the following steps S11 to S13 can be used but are not limited to determine the aforementioned head-end reflection coefficient spectrum.

[0082] S11. Obtain the cable parameters of the aviation cable, and calculate the characteristic impedance of the aviation cable based on the cable parameters; in this embodiment, the cable parameters may include, but are not limited to: the end load impedance of the aviation cable, the length of the aviation cable, and the cable wave velocity, unit inductance and unit capacitance of the aviation cable; therefore, the ratio of the unit inductance to the unit capacitance may be calculated first; then, the square root of the ratio may be calculated; finally, the characteristic impedance of the aviation cable may be obtained based on the square root; optionally, the positive square root of the square root of the ratio may be used as the characteristic impedance of the aviation cable; in this way, after calculating the characteristic impedance of the aviation cable, the corresponding reflection parameters may be calculated based on this, so that the reflection coefficient spectrum of the first end of the aviation cable may be obtained by using the reflection parameters later.

[0083] The calculation process of the reflection parameter may be, but is not limited to, as shown in the following step S12.

[0084] S12. Calculate the reflection parameters of the aviation cable according to the characteristic impedance and the cable parameters. In a specific implementation, the reflection parameters may be calculated according to, but not limited to, the end load impedance of the aviation cable and the characteristic impedance. At the same time, this embodiment provides one of the calculation formulas for the reflection parameters, as shown in the following formula (1).

[0085] (1)

[0086] In the above formula (1), represents the reflection parameter of the aviation cable, represents the end load impedance of the aviation cable, represents the characteristic impedance.

[0087] Thus, after the reflection parameters of the aviation cable are calculated based on the aforementioned formula (1), the head-end reflection coefficient spectrum of the aviation cable can be calculated by combining the aforementioned cable parameters and the test frequencies of each sweep frequency signal, wherein the aforementioned calculation process can be but is not limited to the following step S13.

[0088] S13. Calculate the head-end reflection coefficient spectrum of the aviation cable according to the reflection parameter, the cable parameter and the test frequency of each sweep signal; in a specific application, the head-end reflection coefficient spectrum can be calculated according to, but not limited to, the following formula (2).

[0089] (2)

[0090] In the above formula (2), represents the head-end reflection coefficient spectrum, represents the nth test frequency, Indicates the length of the aviation cable, is the signal transmission attenuation constant, represents the cable wave velocity of the aviation cable, represents the imaginary unit, where ,and Indicates the total number of test frequencies; in this embodiment, the cable wave velocity is the propagation speed of electromagnetic waves in the aviation cable, and its value is , and the signal transmission attenuation constant refers to the ratio of signal power attenuation when the signal is transmitted per unit length of cable, which can be calculated in advance based on the signal strength of the input aviation cable and the output aviation cable; optionally, this embodiment stores the signal transmission attenuation constant in the reflection coefficient spectrum analyzer in advance, so as to facilitate its call to calculate the head-end reflection coefficient spectrum.

[0091] It can be seen from the above formula (2) that the head-end reflection coefficient spectrum is related to the test frequency of the input sweep signal, that is, each sweep signal will calculate a head-end reflection coefficient, and after inputting several sweep signals with different test frequencies into the aviation cable, several head-end reflection coefficients can be obtained, and several head-end reflection coefficients can constitute the head-end reflection coefficient spectrum.

[0092] In this way, through the aforementioned steps S11 to S13, the swept frequency signal can be used to calculate the head-end reflection coefficient spectrum of the aviation cable; then, it is transmitted to the computer in the aircraft fault maintenance management terminal, so that the computer can construct a fault detection distance function of the aviation cable based on this, so as to combine the aforementioned head-end reflection coefficient spectrum to establish a fault diagnosis function of the aviation cable, so as to complete the fault detection of the aviation cable with the help of the fault diagnosis function; wherein, the construction process of the fault detection distance function and the fault diagnosis function can be but is not limited to as shown in the following step S2.

[0093] S2. Constructing a fault detection distance function of the aviation cable, and generating a fault diagnosis function of the aviation cable based on the head end reflection coefficient spectrum and the fault detection distance function; in this embodiment, the reason for generating a fault diagnosis function by establishing a fault detection distance function and combining the head end reflection coefficient spectrum is:

[0094] First, take the real part of the reflection coefficient spectrum at the head end, which is: .

[0095] Through its analysis, it can be seen that when the end load impedance of the aviation cable is greater than the characteristic impedance (that is, there is an increase in impedance at the end of the aviation cable, that is, Greater than ), at this time, the reflection parameter is greater than 0, and is also greater than 0, so the entire real part is also greater than 0; similarly, when the load impedance at the end of the aviation cable is less than the characteristic impedance (that is, there is a reduction in impedance at the end of the aviation cable), the reflection parameter is less than 0, and is greater than 0; at this time, the entire real part is less than 0; based on this, the positive and negative value of the aforementioned real part is related to the impedance of the cable, and the impedance of the cable can reflect the state of the cable.

[0096] Therefore, a fault detection scenario is introduced, that is, when a fault occurs x meters away from the head end of the aviation cable, reflection will also occur at the position of x meters, and there will also be corresponding impedance changes; based on this, the fault detection distance and the head end reflection coefficient spectrum can be combined to construct a diagnostic function for aviation cable fault detection; of course, the specific construction process is described below.

[0097] Thus, through the above analysis, this embodiment needs to first construct a fault detection distance function so as to combine it with the above head-end reflection coefficient spectrum to establish a fault diagnosis function; wherein, for example, but not limited to, the following steps S21 to S23 may be used to establish the above fault detection distance function.

[0098] S21. According to the length of the aviation cable, the maximum fault detection distance and the minimum fault detection distance are determined; in this embodiment, the maximum fault detection distance may be, but is not limited to, 1.1 , and the minimum distance for fault detection can be 0.05 Of course, the aforementioned maximum distance and minimum distance for fault detection can be specifically set according to actual use and are not limited thereto.

[0099] After obtaining the maximum fault detection distance and the minimum fault detection distance, the number of fault detection distance sampling points can be calculated based on this, so as to subsequently generate a fault detection distance function according to the number of fault detection distance sampling points; wherein, the calculation process of the number of fault detection distance sampling points can be but is not limited to as shown in the following step S22.

[0100] S22. Based on the maximum fault detection distance and the minimum fault detection distance, the number of fault detection distance sampling points is calculated. In a specific implementation, the number of fault detection distance sampling points can be calculated by, but not limited to, the following formula (3).

[0101] (3)

[0102] In the above formula (3), represents the number of sampling points of the fault detection distance, represents the maximum fault detection distance, represents the minimum distance for fault detection, represents the fault detection interval distance, and Indicates the rounding down operator; optionally, the fault detection interval distance is used to determine the accuracy of fault location, and the smaller the value, the higher the accuracy; therefore, in this embodiment, taking into account the accuracy and the amount of calculation, the value is set to 0.01m.

[0103] Thus, based on the above formula (3), the number of sampling points of the fault detection distance can be determined; then, the fault detection distance function can be constructed in combination with the above minimum fault detection distance, and the process can be but not limited to the following step S23.

[0104] S23. Constructing a fault detection distance function of the aviation cable according to the minimum fault detection distance and the number of fault detection distance sampling points; in a specific application, the fault detection distance function may be constructed by, for example but not limited to, the following formula (4).

[0105] (4)

[0106] In the above formula (4), represents the fault detection distance function, Indicates the sequence number of the fault detection distance sampling point, where: In this embodiment, it is assumed that is 20, then the fault detection distance sampling points are numbered 1, 2, ..., 20 in sequence; therefore, each fault detection distance sampling point corresponds to a fault detection distance. For example, when k is 1, the fault detection distance corresponding to the fault detection distance sampling point numbered 1 is Similarly, when k is 2, the fault detection distance corresponding to the fault detection distance sampling point with sequence number 2 is: Of course, the calculation process of the fault detection distances corresponding to the remaining fault detection distance sampling points is the same as the above example and will not be repeated here.

[0107] Therefore, after constructing the fault detection distance function through the aforementioned steps S21 to S23, the aforementioned fault diagnosis function can be established in combination with the head end reflection coefficient spectrum of the aviation cable, and the process can be but not limited to as shown in the following steps S24 to S26.

[0108] S24. Generate a fault detection distance and test frequency function according to the fault detection distance function and each test frequency; in the present embodiment, this step is to establish a correlation function between the fault detection distance and the test frequency, so that the correlation function can be used to compare and quantify the reflection coefficient spectrum of the head end of the aviation cable, thereby generating a corresponding fault diagnosis function; wherein, for example, the following formula (5) can be used, but is not limited to, to generate the fault detection distance and test frequency function.

[0109] (5)

[0110] In the above formula (5), represents the function of the fault detection distance and the test frequency, represents the nth test frequency, represents the cable wave velocity of the aviation cable, represents the fault detection distance function, Indicates the sequence number of the fault detection distance sampling point, where: , ,and represents the total number of test frequencies, Indicates the number of fault detection distance sampling points.

[0111] It can be seen from the above formula (5) that if the test frequency (i.e. ) as a variable, then, It has the same functional characteristics as the aforementioned head-end reflection coefficient spectrum (in this embodiment, it refers to its real part), that is, when When the fault detection distance is equal to the length of the aviation cable, the above-mentioned fault detection distance and test frequency function is:

[0112] ;

[0113] The reflection coefficient spectrum at the head end (only its real part is analyzed) is:

[0114] .

[0115] By comparing the two, we can see that the only difference between the two is that the reflection coefficient spectrum at the head end has more ,and is a constant; therefore, when equal When , the fault detection distance and test frequency function have the same waveform characteristics as the head-end reflection coefficient spectrum, only the amplitude is different, and the two are highly correlated; similarly, if the end load impedance of the aviation cable decreases, then the two are negatively correlated. Conversely, if the end load impedance of the aviation cable increases, then the two are negatively correlated (i.e. The different positive and negative values ​​of result in different correlation states between the two).

[0116] Based on this, the aforementioned fault detection distance and test frequency function, and the correlation between the first-end reflection coefficient spectrum, can be used to perform fault detection; therefore, this embodiment constructs a fault diagnosis function based on this, that is, the fault diagnosis function reflects the correlation between the fault detection distance and test frequency function, and the first-end reflection coefficient spectrum; wherein, the specific construction process of the fault diagnosis function can be but is not limited to as shown in the following steps S25 and S26.

[0117] S25. Based on the head-end reflection coefficient spectrum, the mean reflection coefficient of the aviation cable is calculated; in the present embodiment, it has been explained above that the sweep frequency signals of different test frequencies correspond to a head-end reflection coefficient, therefore, by taking the mean of all the head-end reflection coefficients, the mean reflection coefficient can be obtained; then, the fault detection distance and the test frequency function and the head-end reflection coefficient spectrum can be combined to construct a fault diagnosis function, and the process can be but is not limited to as shown in the following step S26.

[0118] S26. Generate a fault diagnosis function of the aviation cable using the head-end reflection coefficient spectrum, the reflection coefficient mean, and the fault detection distance and test frequency function; in this embodiment, for example, but not limited to, first determine the function mean of the fault detection distance and test frequency function at each fault detection distance based on the fault detection distance and test frequency function; then, generate the fault diagnosis function of the aviation cable based on the head-end reflection coefficient spectrum, the reflection coefficient mean, the fault detection distance and test frequency function, and the function mean of the fault detection distance and test frequency function at each fault detection distance.

[0119] Optionally, the fault diagnosis function may be generated by, for example but not limited to, using the following formula (6).

[0120] (6)

[0121] In the above formula (6), represents the fault diagnosis function, represents the head-end reflection coefficient spectrum, represents the mean value of the reflection coefficient, It represents the function of fault detection distance and test frequency. The function mean at the fault detection distance corresponding to the fault detection distance sampling point of Represents the real part operation.

[0122] In this embodiment, The calculation method of is as follows: Referring to the above formula (5), it can be seen that when the fault detection distance is constant, for example, at the fault detection distance corresponding to the fault detection distance sampling point with the serial number 1, each time a test frequency is substituted into formula (5), a function value can be obtained. Therefore, when all test frequencies are substituted into formula (5), N function values ​​will be obtained; then, the average of the N function values ​​is obtained, and Of course, the calculation process of the function mean under other fault detection distances is the same as the above example and will not be repeated here.

[0123] At the same time, it can be seen from the above formula (6) that each time a fault detection distance is obtained from the fault detection function, that is, a fault detection distance is substituted into formula (6), at this time, all test frequencies need to be substituted into formula (6) respectively, so that each fault detection distance will correspond to a function value of a fault diagnosis function, and the function value of the fault diagnosis function is the cable fault characteristic value, which is used to characterize the correlation between the above fault detection distance and the test frequency function and the head-end reflection coefficient spectrum at the fault detection distance; thus, through the above formula (6), it is equivalent to obtaining the correlation between the fault detection distance and the test frequency function and the head-end reflection coefficient spectrum at each fault detection distance; based on this, the cable fault characteristic values ​​at different fault detection distances can be used to locate and identify the faults of aviation cables.

[0124] After the fault diagnosis function is constructed through the aforementioned steps S24 to S26, the fault location and identification of the aviation cable can be performed based on the fault diagnosis function. The process can be but is not limited to the following steps S3 to S5.

[0125] S3. Generate a fault diagnosis waveform of the aviation cable according to the fault diagnosis function of the aviation cable, wherein the horizontal axis of the fault diagnosis waveform is the fault detection distance and the vertical axis is the cable fault characteristic value. In this embodiment, the fault detection distances corresponding to the fault detection distance sampling points with different serial numbers are directly obtained according to the fault detection distance function. Then, the different fault detection distances and each test frequency are substituted into the above formula (6) to obtain the fault diagnosis function value (i.e., the cable fault characteristic value) at each fault detection distance. Then, based on this, a fault diagnosis waveform of the aviation cable can be generated.

[0126] After the fault diagnosis waveform of the aviation cable is obtained, the fault location and identification of the aviation cable can be performed based on the waveform, and the process is shown in the following steps S4 and S5.

[0127] S4. Determine the cable fault characteristic extreme point from the fault diagnosis waveform, determine the impedance state of the aviation cable according to the polarity of the cable fault characteristic extreme point, and determine the fault position of the aviation cable according to the fault detection distance corresponding to the cable fault characteristic extreme point; in this embodiment, it has been explained above that the function value of the fault diagnosis function is used to characterize the correlation between the fault detection distance and the test frequency function and the head-end reflection coefficient spectrum; therefore, the larger the absolute value of the function value of the fault diagnosis function, the more correlated the two are, and conversely, the smaller the absolute value of the function value, the less correlated the two are; and as reflected in FIG. As shown in the figure, the function value is the amplitude; therefore, the amplitude extreme point (i.e., the cable fault characteristic extreme point) can be determined from the fault diagnosis waveform; then, according to the polarity of the extreme point, it can be determined whether the fault detection distance and the test frequency function are in a positive correlation or a negative correlation with the head-end reflection coefficient spectrum; further, the positive and negative correlation states represent the impedance state of the aviation cable, and the impedance state can reflect the existence of the fault; therefore, the cable fault characteristic extreme point is the characteristic reflected by the fault point on the aviation cable, based on this, the fault location and identification of the aviation cable can be completed according to the cable fault characteristic extreme point.

[0128] Specifically, in this embodiment, the fault detection distance corresponding to the extreme point of the cable fault characteristic is used as the distance between the fault point and the head end of the aviation cable; in this way, the fault position of the aviation cable can be determined based on the distance between the fault point and the head end of the aviation cable; if the fault detection distance corresponding to the extreme point of the cable fault characteristic is 5m, then the fault position of the aviation cable is 5m away from the head end of the aviation cable; of course, when the extreme point of the cable fault characteristic is different, the principle of determining the fault position is the same as the above example, and will not be repeated here.

[0129] After completing the fault location, it may be necessary to identify the fault type. In this embodiment, it is first determined whether the polarity of the cable fault characteristic extreme point is positive, that is, whether the cable fault characteristic extreme point is a maximum point; if so, it is determined that the impedance state of the aviation cable is an impedance increase state; otherwise, it is determined that the impedance state of the aviation cable is an impedance decrease state (that is, when the cable fault characteristic extreme point is a minimum point, it is determined that the aviation cable is in an impedance increase state).

[0130] Thus, after the impedance state of the aviation cable at the fault position is obtained based on the above method, the fault type can be identified based on the impedance state, and the process can be but not limited to the following step S5.

[0131] S5. Based on the impedance state, the fault type of the aviation cable is obtained, and the fault location and fault type of the aviation cable are recorded in the fault log and sent to the maintenance terminal, so as to complete the fault maintenance management of the target aircraft after sending; in this embodiment, if the impedance state is an impedance increase state, it is determined that the fault type of the aviation cable is an open circuit fault; and if the impedance state is an impedance decrease state, it is determined that the fault type of the aviation cable is a short circuit fault.

[0132] At the same time, after the fault type of the aviation cable is obtained, for example, but not limited to, based on the fault type of the aviation cable, a maintenance plan corresponding to the fault type can be matched from the aircraft fault maintenance plan library, and the matched maintenance plan is sent to the maintenance terminal together with the fault location and fault type of the aviation cable, so as to facilitate aircraft maintenance personnel to quickly repair the aviation cable; in addition, the aforementioned matched maintenance plan, fault location and fault type can also be recorded together in the maintenance log for data retention and data tracing.

[0133] Thus, through the aircraft fault maintenance management method described in detail in the aforementioned steps S1 to S5, the present invention uses the head-end reflection coefficient spectrum of the aviation cable and combines it with the fault detection distance function of the aviation cable to construct a fault diagnosis function, and then, the polarity and position of the extreme points of the function waveform diagram can be used to determine the fault location and impedance state of the aviation cable; finally, the impedance state of the aviation cable can be used to obtain its fault type; thus, compared with the traditional technology, the present invention does not need to perform fast Fourier transform or inverse transform on the reflection coefficient spectrum, is not affected by the number of test points, and does not need to rewrite the reflection coefficient spectrum data, thereby improving the accuracy of aviation cable fault detection, making it very suitable for large-scale application and promotion.

[0134] like Figure 2 As shown, the second aspect of this embodiment provides a hardware system for implementing the aircraft fault maintenance management method described in the first aspect of the embodiment, including:

[0135] The frequency sweeping unit is used to transmit frequency sweeping signals of different test frequencies to the aviation cable on the target aircraft, so as to determine the head-end reflection coefficient spectrum of the aviation cable based on each frequency sweeping signal.

[0136] The function construction unit is used to construct a fault detection distance function of the aviation cable, and generate a fault diagnosis function of the aviation cable based on the head end reflection coefficient spectrum and the fault detection distance function.

[0137] The feature extraction unit is used to generate a fault diagnosis waveform diagram of the aviation cable according to the fault diagnosis function of the aviation cable, wherein the horizontal axis of the fault diagnosis waveform diagram is the fault detection distance and the vertical axis is the cable fault characteristic value.

[0138] A fault diagnosis unit is used to determine the cable fault characteristic extreme point from the fault diagnosis waveform, and determine the impedance state of the aviation cable according to the polarity of the cable fault characteristic extreme point, and determine the fault position of the aviation cable according to the fault detection distance corresponding to the cable fault characteristic extreme point.

[0139] The fault diagnosis unit is also used to derive the fault type of the aviation cable based on the impedance state, and record the fault location and fault type of the aviation cable in a fault log, and send it to a maintenance terminal, so as to complete the fault maintenance management of the target aircraft after sending.

[0140] The working process, working details and technical effects of the system provided in this embodiment can be found in the first aspect of the embodiment and will not be described in detail here.

[0141] like Figure 3 As shown, the third aspect of this embodiment provides an aircraft fault maintenance management device, taking the device as an electronic device as an example, comprising: a memory, a processor and a transceiver that are communicatively connected in sequence, wherein the memory is used to store computer programs, the transceiver is used to send and receive messages, and the processor is used to read the computer program to execute the aircraft fault maintenance management method as described in the first aspect of the embodiment.

[0142] For example, the memory may include, but is not limited to, random access memory (RAM), read only memory (ROM), flash memory, first input first output (FIFO) and / or first in last out (FILO), etc. Specifically, the processor may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor may be implemented in at least one hardware form of DSP (Digital Signal Processing), FPGA (Field-Programmable Gate Array), and PLA (Programmable Logic Array). At the same time, the processor may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a CPU (Central Processing Unit); the coprocessor is a low-power processor for processing data in the standby state.

[0143] In some embodiments, the processor may be integrated with a GPU (Graphics Processing Unit), which is responsible for rendering and drawing the content to be displayed on the display screen. For example, the processor may not be limited to a microprocessor of the STM32F105 series, a reduced instruction set computer (RISC) microprocessor, an X86 architecture processor, or a processor with an integrated embedded neural network processing unit (NPU); the transceiver may be, but is not limited to, a wireless fidelity (WIFI) wireless transceiver, a Bluetooth wireless transceiver, a General Packet Radio Service (GPRS) wireless transceiver, a ZigBee protocol (a low-power LAN protocol based on the IEEE802.15.4 standard, ZigBee) wireless transceiver, a 3G transceiver, a 4G transceiver, and / or a 5G transceiver. In addition, the device may also include, but is not limited to, a power module, a display screen, and other necessary components.

[0144] The working process, working details and technical effects of the electronic device provided in this embodiment can be found in the first aspect of the embodiment and will not be described in detail here.

[0145] A fourth aspect of this embodiment provides a storage medium storing instructions including the aircraft fault maintenance management method described in the first aspect of the embodiment, that is, the storage medium stores instructions, and when the instructions are run on a computer, the aircraft fault maintenance management method described in the first aspect of the embodiment is executed.

[0146] The storage medium refers to a carrier for storing data, which may include but is not limited to a floppy disk, a CD, a hard disk, a flash memory, a USB flash drive and / or a memory stick, and the computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices.

[0147] The working process, working details and technical effects of the storage medium provided in this embodiment can be found in the first aspect of the embodiment and will not be described in detail here.

[0148] A fifth aspect of the present embodiment provides a computer program product comprising instructions, which, when executed on a computer, causes the computer to execute the aircraft fault maintenance management method as described in the first aspect of the embodiment, wherein the computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device.

[0149] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An aircraft fault maintenance management method, characterized in that: include: Transmitting sweep frequency signals of different test frequencies to the aviation cable on the target aircraft, so as to determine the head-end reflection coefficient spectrum of the aviation cable based on each sweep frequency signal; Constructing a fault detection distance function of the aviation cable, and generating a fault diagnosis function of the aviation cable based on the head end reflection coefficient spectrum and the fault detection distance function; According to the fault diagnosis function of the aviation cable, a fault diagnosis waveform diagram of the aviation cable is generated, wherein the horizontal axis of the fault diagnosis waveform diagram is the fault detection distance, and the vertical axis is the cable fault characteristic value; Determine the cable fault characteristic extreme value point from the fault diagnosis waveform diagram, determine the impedance state of the aviation cable according to the polarity of the cable fault characteristic extreme value point, and determine the fault position of the aviation cable according to the fault detection distance corresponding to the cable fault characteristic extreme value point; Based on the impedance state, the fault type of the aviation cable is obtained, and the fault location and fault type of the aviation cable are recorded in a fault log, and sent to a maintenance terminal, so as to complete the fault maintenance management of the target aircraft after sending; Based on the head-end reflection coefficient spectrum and the fault detection distance function, a fault diagnosis function of the aviation cable is generated, including: Generating a fault detection distance and test frequency function according to the fault detection distance function and each test frequency; Based on the head-end reflection coefficient spectrum, calculating the reflection coefficient mean value of the aviation cable; Generate a fault diagnosis function of the aviation cable by using the head-end reflection coefficient spectrum, the reflection coefficient mean value, and the fault detection distance and test frequency function; Generating a fault detection distance and test frequency function according to the fault detection distance function and each test frequency includes: According to the following formula (5), the fault detection distance and test frequency function is generated; （5） In the above formula (5), represents the function of the fault detection distance and the test frequency, represents the nth test frequency, represents the cable wave velocity of the aviation cable, represents the fault detection distance function, Indicates the sequence number of the fault detection distance sampling point, where: , ,and represents the total number of test frequencies, Indicates the number of fault detection distance sampling points; Correspondingly, the fault diagnosis function of the aviation cable is generated by using the head-end reflection coefficient spectrum, the reflection coefficient mean value, and the fault detection distance and test frequency function, which includes: According to the fault detection distance and test frequency function, determining a function mean of the fault detection distance and test frequency function at each fault detection distance; Based on the head-end reflection coefficient spectrum, the reflection coefficient mean, the fault detection distance and test frequency function, and the function mean of the fault detection distance and test frequency function at each fault detection distance, and according to the following formula (6), a fault diagnosis function of the aviation cable is generated; （6） In the above formula (6), represents the fault diagnosis function, represents the head-end reflection coefficient spectrum, represents the mean value of the reflection coefficient, It represents the function of fault detection distance and test frequency. The function mean at the fault detection distance corresponding to the fault detection distance sampling point of Represents the real part operation.

2. The method according to claim 1, characterized in that Based on each frequency sweep signal, a reflection coefficient spectrum of the first end of the aviation cable is determined, including: Acquiring cable parameters of the aviation cable, and calculating the characteristic impedance of the aviation cable based on the cable parameters; Calculating reflection parameters of the aviation cable according to the characteristic impedance and the cable parameters; The head-end reflection coefficient spectrum of the aviation cable is calculated according to the reflection parameter, the cable parameter and the test frequency of each frequency sweep signal.

3. The method according to claim 2, characterized in that The cable parameters include: the end load impedance of the aviation cable, the length of the aviation cable, and the cable wave speed, unit inductance and unit capacitance of the aviation cable; Based on the cable parameters, the characteristic impedance of the aviation cable is calculated, including: Calculating a ratio of the unit inductance to the unit capacitance, and obtaining a square root of the ratio, so as to obtain a characteristic impedance of the aviation cable based on the square root; The step of calculating the reflection parameters of the aviation cable according to the characteristic impedance and the cable parameters includes: According to the end load impedance of the aviation cable and the characteristic impedance, and in accordance with the following formula (1), the reflection parameter of the aviation cable is calculated; （1） In the above formula (1), represents the reflection parameter of the aviation cable, represents the end load impedance of the aviation cable, represents the characteristic impedance; Correspondingly, calculating the head-end reflection coefficient spectrum of the aviation cable according to the reflection parameter, the cable parameter and the test frequency of each sweep signal includes: According to the following formula (2), the head end reflection coefficient spectrum is calculated; （2） In the above formula (2), represents the head-end reflection coefficient spectrum, represents the nth test frequency, Indicates the length of the aviation cable, is the signal transmission attenuation constant, represents the cable wave velocity of the aviation cable, represents the imaginary unit, where ,and Indicates the total number of test frequencies.

4. The method according to claim 1, characterized in that: Constructing a fault detection distance function of the aviation cable, including: Determining a maximum fault detection distance and a minimum fault detection distance according to the length of the aviation cable; Calculating the number of fault detection distance sampling points based on the maximum fault detection distance and the minimum fault detection distance; A fault detection distance function of the aviation cable is constructed according to the minimum fault detection distance and the number of fault detection distance sampling points.

5. The method according to claim 4, characterized in that The number of sampling points of the fault detection distance is calculated based on the maximum fault detection distance and the minimum fault detection distance, including: According to the following formula (3), the number of sampling points of the fault detection distance is calculated; （3） In the above formula (3), represents the number of sampling points of the fault detection distance, represents the maximum fault detection distance, represents the minimum distance for fault detection, represents the fault detection interval distance, and Indicates the floor rounding operator symbol; Correspondingly, according to the minimum fault detection distance and the number of fault detection distance sampling points, a fault detection distance function of the aviation cable is constructed, which includes: According to the following formula (4), the fault detection distance function is constructed; （4） In the above formula (4), represents the fault detection distance function, Indicates the sequence number of the fault detection distance sampling point, where: .

6. The method according to claim 1, characterized in that Determining the impedance state of the aviation cable according to the polarity of the cable fault characteristic extreme point, and determining the fault position of the aviation cable according to the fault detection distance corresponding to the cable fault characteristic extreme point, including: Determining whether the polarity of the cable fault characteristic extreme point is positive; If so, it is determined that the impedance state of the aviation cable is an impedance increasing state; otherwise, it is determined that the impedance state of the aviation cable is an impedance decreasing state; The fault detection distance corresponding to the extreme value point of the cable fault characteristic is used as the distance between the fault point and the head end of the aviation cable, so as to determine the fault position of the aviation cable based on the distance between the fault point and the head end of the aviation cable; Accordingly, based on the impedance state, the fault type of the aviation cable is obtained, which includes: If the impedance state is an impedance increase state, it is determined that the fault type of the aviation cable is an open circuit fault; if the impedance state is an impedance decrease state, it is determined that the fault type of the aviation cable is a short circuit fault.

7. An aircraft fault maintenance management system, characterized in that: include: A frequency sweeping unit, used for transmitting frequency sweeping signals of different test frequencies to the aviation cable on the target aircraft, so as to determine the head-end reflection coefficient spectrum of the aviation cable based on each frequency sweeping signal; A function construction unit, used to construct a fault detection distance function of the aviation cable, and generate a fault diagnosis function of the aviation cable based on the head end reflection coefficient spectrum and the fault detection distance function; A feature extraction unit, used to generate a fault diagnosis waveform diagram of the aviation cable according to the fault diagnosis function of the aviation cable, wherein the horizontal axis of the fault diagnosis waveform diagram is the fault detection distance, and the vertical axis is the cable fault characteristic value; A fault diagnosis unit, configured to determine a cable fault characteristic extreme value point from the fault diagnosis waveform diagram, determine an impedance state of the aviation cable according to the polarity of the cable fault characteristic extreme value point, and determine a fault position of the aviation cable according to a fault detection distance corresponding to the cable fault characteristic extreme value point; The fault diagnosis unit is further used to obtain the fault type of the aviation cable based on the impedance state, and record the fault location and fault type of the aviation cable in a fault log, and send it to a maintenance terminal, so as to complete the fault maintenance management of the target aircraft after sending; Based on the head-end reflection coefficient spectrum and the fault detection distance function, a fault diagnosis function of the aviation cable is generated, including: Generating a fault detection distance and test frequency function according to the fault detection distance function and each test frequency; Based on the head-end reflection coefficient spectrum, calculating the reflection coefficient mean value of the aviation cable; Generate a fault diagnosis function of the aviation cable by using the head-end reflection coefficient spectrum, the reflection coefficient mean value, and the fault detection distance and test frequency function; Generating a fault detection distance and test frequency function according to the fault detection distance function and each test frequency includes: According to the following formula (5), the fault detection distance and test frequency function is generated; （5） In the above formula (5), represents the function of the fault detection distance and the test frequency, represents the nth test frequency, represents the cable wave velocity of the aviation cable, represents the fault detection distance function, Indicates the sequence number of the fault detection distance sampling point, where: , ,and represents the total number of test frequencies, Indicates the number of fault detection distance sampling points; Correspondingly, the fault diagnosis function of the aviation cable is generated by using the head-end reflection coefficient spectrum, the reflection coefficient mean value, and the fault detection distance and test frequency function, which includes: According to the fault detection distance and test frequency function, determining a function mean of the fault detection distance and test frequency function at each fault detection distance; Based on the head-end reflection coefficient spectrum, the reflection coefficient mean, the fault detection distance and test frequency function, and the function mean of the fault detection distance and test frequency function at each fault detection distance, and according to the following formula (6), a fault diagnosis function of the aviation cable is generated; （6） In the above formula (6), represents the fault diagnosis function, represents the head-end reflection coefficient spectrum, represents the mean value of the reflection coefficient, It represents the function of fault detection distance and test frequency. The function mean at the fault detection distance corresponding to the fault detection distance sampling point of Represents the real part operation.

8. A computer program product comprising instructions, characterized in that When the instructions are executed on a computer, the computer is caused to execute the aircraft failure maintenance management method as claimed in any one of claims 1 to 6.

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