A wiring harness fault diagnosis method, device, equipment and medium

Abstract

This application discloses a method, apparatus, device, and medium for diagnosing wiring harness faults, relating to the field of wiring harness diagnostic technology. It addresses the technical problem in existing technologies where the location of aircraft wiring harness faults cannot be accurately diagnosed, thus affecting safe flight. The method includes sending a diagnostic pulse to the wiring harness to be diagnosed according to a preset amplitude; obtaining a first time based on the diagnostic pulse; wherein the first time is the time of sending the diagnostic pulse; receiving a reflected pulse returned from the fault point of the wiring harness to be diagnosed; obtaining a second time based on the reflected pulse; wherein the second time is the time of receiving the transmitted pulse; and obtaining diagnostic location information of the wiring harness to be diagnosed based on the first and second times. This allows for easier diagnosis of the location of the fault point in the wiring harness, enabling more timely elimination of corresponding faults in the aircraft wiring harness.

Description

Technical Field

[0001] This application relates to the field of wire harness diagnostic technology, and in particular to a method, apparatus, equipment and medium for diagnosing wire harness faults. Background Technology

[0002] Aircraft wiring harnesses are hardware devices that provide power and transmit control signals to the electrical systems of an aircraft. Composed of numerous components such as connecting wires and connectors, they serve as vital energy and information channels connecting the power supply, electromechanical equipment, electronic equipment, and control systems, playing a crucial role in flight control and safety. Therefore, when an aircraft wiring harness malfunctions, it is necessary to quickly locate the fault without removing a large number of wiring harness fixing devices and interlayers.

[0003] However, existing technologies cannot accurately diagnose the location of aircraft wiring harness faults, thus affecting the safe flight of the aircraft. Summary of the Invention

[0004] The main purpose of this application is to provide a method, apparatus, equipment and medium for diagnosing wiring harness faults, in order to solve the technical problem that the existing technology cannot accurately diagnose the location of aircraft wiring harness faults, thereby affecting the safe flight of aircraft.

[0005] To achieve the above objectives, the first aspect of this application provides a method for diagnosing wire harness faults, the method comprising:

[0006] Send diagnostic pulses to the harness to be diagnosed according to a preset amplitude;

[0007] Based on the diagnostic pulse, a first time is obtained; wherein, the first time is the time when the diagnostic pulse was sent;

[0008] Receive reflected pulses returned from the fault point of the harness to be diagnosed;

[0009] Based on the reflected pulse, a second time is obtained; wherein, the second time is the time of receiving the transmitted pulse;

[0010] Based on the first time and the second time, the diagnostic location information of the wire harness to be diagnosed is obtained.

[0011] Optionally, obtaining the second time based on the reflected pulse includes:

[0012] Determine whether the received reflected pulses have reached a preset number of times;

[0013] If the received reflected pulses reach the preset number of times, the reflected pulses of the preset number of times are aligned and sorted to obtain a second time.

[0014] Optionally, sending a diagnostic pulse to the harness to be diagnosed according to a preset amplitude includes:

[0015] Based on the preset phase shift time, a diagnostic pulse is sent to the harness to be diagnosed according to the preset amplitude.

[0016] Optionally, obtaining the diagnostic location information of the harness to be diagnosed based on the first time and the second time includes:

[0017] A fault point model is constructed based on the pulse propagation speed in the harness to be diagnosed, the first time, and the second time.

[0018] Based on the fault point model, the diagnostic location information of the harness to be diagnosed is obtained.

[0019] Optionally, the step of constructing a fault point model based on the pulse propagation speed in the harness to be diagnosed, the first time, and the second time includes:

[0020] The fault point model is obtained using the following formula:

[0021]

[0022]

[0023] Where L represents the location of the fault point, t1 represents the first time point, t2 represents the second time point, and v p ε represents the propagation speed of the pulse in the cable medium, u represents the relative permeability of the cable medium, and ε represents the velocity of the pulse. r represents the relative permittivity of the cable, and c represents the speed of light.

[0024] Optionally, after the step of obtaining the diagnostic location information of the harness to be diagnosed based on the first time and the second time, the method further includes:

[0025] Obtain the load impedance and characteristic impedance of the fault point of the harness to be diagnosed;

[0026] Based on the load impedance and the characteristic impedance, a reflection coefficient model of the wire harness to be diagnosed is constructed;

[0027] Based on the reflection coefficient model, the fault type information of the harness to be diagnosed is obtained.

[0028] Optionally, constructing the reflection coefficient model of the harness to be diagnosed based on the load impedance and the characteristic impedance includes:

[0029] The reflection coefficient model of the wire harness to be diagnosed is constructed using the following formula:

[0030]

[0031]

[0032] Where ρ represents the reflection coefficient of the wire bundle to be diagnosed, and Z L Z0 represents the load impedance at the fault point of the wire harness to be diagnosed, M represents the inductance of the wire harness to be diagnosed, and C represents the capacitance of the wire harness to be diagnosed.

[0033] Optionally, obtaining the fault type information of the harness to be diagnosed based on the reflection coefficient model includes:

[0034] When the reflection coefficient ρ of the wire harness to be diagnosed is 0, the wire harness to be diagnosed is fault-free;

[0035] When the reflection coefficient ρ of the wire harness to be diagnosed is 1, the wire harness to be diagnosed is open-circuited;

[0036] When the reflection coefficient ρ of the wire harness to be diagnosed is -1, the wire harness to be diagnosed is short-circuited;

[0037] When the reflection coefficient of the wire harness to be diagnosed is -1 < ρ < 1, the insulation of the wire harness to be diagnosed will wrinkle or wear.

[0038] Secondly, this application provides a wire harness fault diagnosis device, the device comprising:

[0039] The transmitting module is used to send diagnostic pulses to the wire harness to be diagnosed according to a preset amplitude.

[0040] A first obtaining module is configured to obtain a first time based on the diagnostic pulse; wherein, the first time is the time when the diagnostic pulse was sent;

[0041] The second acquisition module is used to receive reflected pulses returned from the fault point of the harness to be diagnosed;

[0042] The third obtaining module is used to obtain a second time based on the reflected pulse; wherein the second time is the time of receiving the transmitted pulse;

[0043] The fourth obtaining module is used to obtain the diagnostic location information of the wire harness to be diagnosed based on the first time and the second time.

[0044] Thirdly, this application provides a computer device including a memory and a processor, wherein the memory stores a computer program and the processor executes the computer program to implement the methods described in the embodiments.

[0045] Fourthly, this application provides a computer-readable storage medium storing a computer program, on which a processor executes the computer program to implement the methods described in the embodiments.

[0046] Through the above technical solution, this application has at least the following beneficial effects:

[0047] The wiring harness fault diagnosis method, apparatus, device, and medium proposed in this application send a diagnostic pulse to the wiring harness to be diagnosed according to a preset amplitude; obtain a first time based on the diagnostic pulse; wherein the first time is the time of sending the diagnostic pulse; receive a reflected pulse returned from the fault point of the wiring harness to be diagnosed; obtain a second time based on the reflected pulse; wherein the second time is the time of receiving the transmitted pulse; and obtain diagnostic location information of the wiring harness to be diagnosed based on the first time and the second time.

[0048] In other words, when diagnosing a fault in the wiring harness, a diagnostic pulse is first sent to the harness. Then, a first time is obtained based on this pulse. Next, the reflected pulse from the fault point in the harness is received, and a second time is obtained upon receiving the reflected pulse. Thus, the location of the fault point in the harness can be diagnosed based on the first and second times. Specifically, because this method utilizes the pulse propagation speed in the harness, the first time the pulse begins to occur, and the second time the returned pulse is received, the total time from sending to receiving the pulse can be determined. Based on the relationship that the pulse propagation path equals the propagation speed multiplied by the propagation time, the location of the fault point in the harness can be diagnosed more easily. This allows for more timely elimination of corresponding faults in the aircraft wiring harness, thereby better ensuring safer flight. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of the computer device structure for the hardware operating environment involved in the embodiments of this application;

[0050] Figure 2 A flowchart illustrating a wire harness fault diagnosis method provided in this application embodiment;

[0051] Figure 3 A schematic diagram of the pulse generation circuit provided in an embodiment of this application;

[0052] Figure 4 A schematic diagram of the pulses emitted by the fault diagnostic instrument provided in the embodiments of this application;

[0053] Figure 5 A schematic diagram of pulse distortion emitted by the fault diagnostic instrument provided in an embodiment of this application;

[0054] Figure 6 A schematic diagram of the pulses emitted by the fault diagnostic instrument in the embodiments of this application when increasing the sampling frequency;

[0055] Figure 7 This is a flowchart illustrating a specific execution method for step S13 provided in this embodiment;

[0056] Figure 8 A schematic diagram illustrating the alignment and sorting of reflected pulses provided in the embodiments of this application;

[0057] Figure 9 A schematic diagram of the fourth sampling data provided in the embodiments of this application;

[0058] Figure 10 This is a flowchart illustrating a specific execution method for step S14 provided in this embodiment;

[0059] Figure 11 This is a flowchart illustrating the process of obtaining the fault point type provided in an embodiment of this application;

[0060] Figure 12 A schematic diagram of the equivalent distributed parameter model of the wire harness to be diagnosed provided in the embodiments of this application;

[0061] Figure 13 This is a schematic diagram of a wire harness fault diagnosis device provided in an embodiment of this application.

[0062] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0063] It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0064] Aircraft wiring harnesses are hardware devices on an aircraft that provide power and transmit control signals to the electrical system. Composed of numerous components such as connecting wires and connectors, they serve as vital energy and information channels connecting the power supply, electromechanical equipment, electronic equipment, and control systems, playing a crucial role in flight control and safety. If an aircraft wiring harness malfunctions, it is necessary to quickly locate the fault without removing a large number of wiring harness fixing devices and interlayers. However, currently, it is not possible to accurately diagnose the location of aircraft wiring harness faults, thus affecting safe flight operations.

[0065] To address the aforementioned technical problems, this application provides a method, apparatus, device, and medium for diagnosing wire harness faults. Before introducing the specific technical solutions of this application, the hardware operating environment involved in the embodiments of this application will be described first.

[0066] Reference Figure 1 , Figure 1 This is a schematic diagram of the computer device structure of the hardware operating environment involved in the embodiments of this application.

[0067] like Figure 1 As shown, the computer device may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to enable communication between these components. The user interface 1003 may include a display screen and an input unit such as a keyboard; optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface). The memory 1005 may be a high-speed random access memory (RAM) or a stable non-volatile memory (NVM), such as a disk drive. The memory 1005 may also optionally be a storage device independent of the aforementioned processor 1001.

[0068] Those skilled in the art will understand that Figure 1 The structure shown does not constitute a limitation on the computer device and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0069] like Figure 1 As shown, the memory 1005, which serves as a storage medium, may include an operating system, a data storage module, a network communication module, a user interface module, and electronic programs.

[0070] exist Figure 1 In the computer device shown, the network interface 1004 is mainly used for data communication with the network server; the user interface 1003 is mainly used for data interaction with the user; the processor 1001 and the memory 1005 in the computer device of this application can be set in the computer device, and the computer device calls the wire harness fault diagnosis device stored in the memory 1005 through the processor 1001 and executes the wire harness fault diagnosis method provided in the embodiment of this application.

[0071] Reference Figure 2 Based on the hardware environment of the foregoing embodiments, embodiments of this application provide a wiring harness fault diagnosis method, the method comprising:

[0072] S10: Send a diagnostic pulse to the harness to be diagnosed according to the preset amplitude.

[0073] In practical implementation, based on a preset phase shift time, a diagnostic pulse is sent to the wiring harness to be diagnosed according to a preset amplitude. Here, the preset time refers to a pre-set time, the wiring harness to be diagnosed is the harness being diagnosed, and the harness being diagnosed generally refers to aircraft wiring harnesses, and the preset amplitude refers to the pre-set amplitude of the diagnostic pulse. The wiring harness to be diagnosed is connected to the pulse transmitter of a device capable of sending diagnostic pulses, and then a diagnostic pulse is sent to the wiring harness to be diagnosed according to the preset amplitude. The device capable of sending diagnostic pulses is, for example, a fault diagnostic instrument, which includes an FPGA, a pulse generation circuit, and a signal acquisition circuit. Figure 3 As shown, Figure 3 This is a schematic diagram of the pulse generation circuit provided in an embodiment of this application. When the diagnostic pulse is sent by this fault diagnostic instrument, the FPGA controls the on / off state of RF transistors T1 and T2 through input interfaces 1 and 2, thereby controlling the width and phase of the generated pulse; the pulse amplitude is adjusted by a low-speed DA converter, and the pulse passes through RF transistor T3; the pulse signal is sent to the sampling circuit and the wire harness to be diagnosed through interface 5. The width of the generated pulse is only limited by the FPGA signal and the switching cutoff frequency of the RF transistors, and is independent of the DA rate. High-speed DA converters are expensive, while high-frequency transistors are inexpensive, thus this fault diagnostic instrument can greatly reduce the diagnostic cost of the wire harness to be diagnosed.

[0074] In addition, the principle of the signal acquisition circuit of this fault diagnostic instrument is as follows: Figure 4 This is a schematic diagram of the pulses emitted by the fault diagnostic instrument provided in the embodiments of this application. Figure 4 The vertical line represents the sampling time interval; that is, the horizontal axis represents time, and the vertical axis represents the pulse propagation speed. When the sampling frequency is low, the waveform reconstructed from the samples will be distorted, as shown below. Figure 5 As shown, Figure 5 This is a schematic diagram illustrating pulse distortion emitted by the fault diagnostic instrument provided in this embodiment of the application. To achieve high data fidelity, the sampling frequency needs to be increased, such as... Figure 6 As shown, Figure 6 This diagram illustrates the pulses emitted by the fault diagnostic instrument provided in this embodiment, which increase the sampling frequency. Therefore, typical time-domain reflectometry (TD-SCADA) chips require a higher sampling frequency to achieve higher positioning accuracy. Because the parameters of the harness to be diagnosed do not change during measurement, measurements are performed by emitting pulses multiple times, with each pulse shifting the phase of the FPGA pulse transmission by the same distance. Figure 6The sampling of N time intervals T in a single operation can be divided into M measurements, with each sampling interval being M×T. Ensuring a phase difference of T between adjacent measurements reduces the required sampling frequency f1 = 1 / T to f2 = 1 / (M×T). By aligning and inserting the measurement data in the original order, and with the FPGA output clock phase meeting the T time interval requirement (or using external hardware), the number of measurements M can be increased to achieve the sampling effect of the original f1 operating frequency. Furthermore, the equivalent sampling frequency f2 is not limited by the AD chip's own operating frequency; the chip frequency only affects the number of samples. The introduction of high-speed AD chips, besides their high cost, also increases the design, manufacturing, and testing costs of high-frequency PCBs. Therefore, this application uses a multi-phase data superposition method. Its sampling frequency is only limited by the minimum division of the clock signal and is independent of the AD chip's sampling frequency. Typically, the clock phase output from the FPGA is sufficient for the requirements, and even external clocks are inexpensive, further significantly reducing the diagnostic cost of the wiring harness being diagnosed. This application uses a multi-phase data superposition method, whose sampling frequency is limited only by the minimum division of the clock signal and is independent of the sampling frequency of the AD chip, thus realizing a low-cost, high-precision, and small-size aircraft wiring harness fault diagnostic instrument.

[0075] S11: Based on the diagnostic pulse, obtain a first time; wherein, the first time is the time when the diagnostic pulse is sent.

[0076] In the specific implementation process, when the diagnostic pulse is sent to the harness to be diagnosed, the time when the diagnostic pulse is sent is recorded and this time is taken as the first time.

[0077] S12: Receive the reflected pulse returned from the fault point of the harness to be diagnosed.

[0078] In the specific implementation process, when the diagnostic pulse propagates in the harness to be diagnosed and encounters a fault point, the diagnostic pulse will be reflected by the fault point. After the reflected diagnostic pulse is received by the fault diagnostic instrument, the returned diagnostic pulse will be used as the reflected pulse.

[0079] S13: Based on the reflected pulse, obtain a second time; wherein the second time is the time of receiving the transmitted pulse.

[0080] In the specific implementation process, the time when the fault diagnostic instrument receives the reflected pulse is recorded and this time is used as the second time.

[0081] S14: Based on the first time and the second time, obtain the diagnostic location information of the wire harness to be diagnosed.

[0082] In the specific implementation process, since the propagation speed of the pulse in the corresponding wire harness to be diagnosed is constant, and the time when the diagnostic pulse is sent and returned after encountering the fault point can be known by the first time and the second time, i.e. the difference between the first time and the second time, the location of the fault point of the wire harness to be diagnosed can be known according to the principle that distance equals speed multiplied by time.

[0083] In this embodiment, when it is necessary to diagnose a fault in the wiring harness to be diagnosed, a diagnostic pulse is first sent to the wiring harness. Then, a first time is obtained based on this pulse. Next, the reflected pulse returned from the fault point of the wiring harness to be diagnosed is received, and a second time is obtained for receiving the reflected pulse. Thus, the location of the fault point in the wiring harness to be diagnosed can be diagnosed based on the first and second times. That is, since this method utilizes the propagation speed of the pulse in the wiring harness to be diagnosed, the first time when the pulse begins to occur, and the second time when the returned pulse is received, the total time taken from sending the pulse to receiving the pulse can be known based on the first and second times. According to the relationship that the propagation path of the pulse is equal to the propagation speed multiplied by the propagation time, the location of the fault point in the wiring harness to be diagnosed can be diagnosed more easily, thereby eliminating the corresponding faults in the aircraft wiring harness more promptly and thus ensuring safer flight of the aircraft.

[0084] In some embodiments, such as Figure 7 As shown, obtaining the second time based on the reflected pulse includes:

[0085] S131: Determine whether the received reflected pulses have reached a preset number of times.

[0086] In practical implementation, the preset number of times refers to the number of samples set in advance. Assuming the AD sampling frequency in the sampling circuit is 100MHz, while the required sampling frequency to accurately identify the transmitted pulse and the aircraft harness reflected pulse is at least 1GHz, it is necessary to repeat the sampling 10 times (i.e., the preset number of times). After each sampling, the FPGA transmitted pulse phase shifts by 1ns (i.e., the preset phase shift time in step S10). That is... Figure 3 As shown, the FPGA controls T4 to turn on, and the FPGA pulse phase shifts by 1ns to send a pulse. After a single sampling is completed, the FPGA controls T5 to turn on, discharging the charge of C1 and preparing for the next sampling.

[0087] S132: When the received reflected pulse reaches the preset number of times, the reflected pulses of the preset number of times are aligned and sorted to obtain a second time.

[0088] In the specific implementation process, before the initial harness diagnosis, it is necessary to determine the corresponding order of each sampled signal superposition and alignment. The 10 sampled data points are then sorted sequentially according to the magnitude of the first non-zero data point. Figure 8 As shown, Figure 8 This is a schematic diagram illustrating the alignment and sorting of reflected pulses provided in an embodiment of this application. Figure 8 The number inside the upper circle indicates the measurement number, and the number below indicates the value's position within the data collected in that particular session. According to... Figure 8 In the example, the correct alignment order is: the second data point of the 10th measurement, the first data point of the 1st measurement, the first data point of the 2nd measurement... the first data point of the 9th measurement, the third data point of the 10th measurement, the second data point of the 1st measurement... and so on. This order can be used to correctly align and sort the data when performing formal wiring harness fault diagnosis.

[0089] However, using the above method introduces a new problem: in actual use, due to issues such as the timing of the transmitted pulse and the sampling clock, the first data sample may be ahead or behind, potentially causing the inserted and superimposed data to be misaligned relative to the actual position. Figure 9 As shown, Figure 9 This is a schematic diagram of the fourth sampling data provided in the embodiments of this application. Figure 9 During the fourth sampling data alignment, the data was misaligned to the right, resulting in an erroneous waveform. Therefore, in Figure 3 In the pulse generation circuit, transistor T4 and capacitor C1 form an initialization circuit. During initialization, the FPGA controls transistor T5 to conduct and controls the pulse signal width to match that of capacitor C1, so that the pulse arriving at the measurement end tends to increase gradually. After a single measurement, the FPGA controls transistor T5 to conduct, releasing the charge of capacitor C1. This process is repeated to obtain the amplitude of the measurement signal for each phase. The signal alignment position of each phase can be determined by the amplitude. Each time the harness sampling data is collected, it can be aligned in this order to avoid... Figure 9 The data is misaligned. By aligning and sorting the reflected pulses as described above, a more accurate second time can be obtained.

[0090] In some embodiments, such as Figure 10 As shown, obtaining the diagnostic location information of the harness to be diagnosed based on the first time and the second time includes:

[0091] S141: Construct a fault point model based on the propagation speed of the pulse in the harness to be diagnosed, the first time, and the second time.

[0092] In some embodiments, the propagation speed of the pulse in the wiring harness under test is related to the dielectric constant of the wiring harness under test; therefore, knowing the dielectric constant of the wiring harness under test allows us to determine the propagation speed of the pulse in the wiring harness under test. Specifically, the fault point model is obtained using the following formula:

[0093]

[0094] Where L represents the location of the fault point, t1 represents the first time point, t2 represents the second time point, and v p This indicates the propagation speed of the pulse in the cable medium.

[0095] At very high frequencies, the propagation speed of electromagnetic waves in a cable approaches a constant, which can be approximated as:

[0096]

[0097] Where u represents the relative permeability of the cable medium, ε r represents the relative permittivity of the cable, and c represents the speed of light.

[0098] S142: Based on the fault point model, obtain the diagnostic location information of the harness to be diagnosed.

[0099] In some embodiments, given the propagation speed of the pulse in the harness to be diagnosed, the first time, and the second time, the location of the fault point in the harness to be diagnosed can be quickly and accurately calculated using the fault point model described above.

[0100] In some embodiments, such as Figure 11 As shown, after the step of obtaining the diagnostic location information of the harness to be diagnosed based on the first time and the second time, the method further includes:

[0101] S20: Obtain the load impedance and characteristic impedance of the fault point of the harness to be diagnosed.

[0102] In practical implementation, under ideal conditions, the cable harness to be diagnosed can be considered as a uniform transmission line. Therefore, it is feasible to use distributed parameters to describe the cable model. The equivalent distributed parameter model is as follows: Figure 12 As shown, Figure 12 This is a schematic diagram of the equivalent distributed parameter model of the wire harness to be diagnosed provided in an embodiment of this application. Figure 12 In this diagram, R, L, C, and G represent the distributed resistance, inductance, capacitance, and conductance per unit length of the transmission line, respectively. The load impedance and characteristic impedance of the fault point in the harness to be diagnosed are obtained using conventional methods.

[0103] S21: Based on the load impedance and the characteristic impedance, construct the reflection coefficient model of the wire harness to be diagnosed.

[0104] In the specific implementation process, the reflection coefficient model of the wire harness to be diagnosed is constructed using the following formula:

[0105]

[0106] Where ρ represents the reflection coefficient of the wire bundle to be diagnosed, and ZL Z0 represents the load impedance at the fault point of the harness to be diagnosed, and Z0 represents the characteristic impedance of the harness to be diagnosed.

[0107] The characteristic impedance is the ratio of the incident wave voltage to the incident wave current, from which we can obtain:

[0108]

[0109] The formula above shows that the characteristic impedance Z0 is related to R, L, G, C, and the operating frequency ω. Among these, the capacitance C and inductance L are related to factors such as the dielectric constant of the cable and the cross-sectional area of ​​the core wire, indicating that different types of cables have different wave impedances. For transmission lines with low loss, since:

[0110] ωL>>R

[0111] ωC>>G

[0112] Therefore, the characteristic impedance Z0 can be simplified to:

[0113]

[0114] Where M represents the inductance of the harness to be diagnosed, and C represents the capacitance of the harness to be diagnosed.

[0115] S22: Based on the reflection coefficient model, obtain the fault type information of the harness to be diagnosed.

[0116] In practical implementation, when the reflection coefficient ρ of the wire harness to be diagnosed is 0, it indicates that the wire harness cable is normal, and the load impedance and characteristic impedance are matched, i.e., Z... L =Z0, at which point there is no reflected echo.

[0117] When the reflection coefficient ρ of the wire harness to be diagnosed is 1, it indicates that the wire harness to be diagnosed has an open circuit. L =∞, the incident wave and the reflected wave have the same polarity;

[0118] When the reflection coefficient ρ of the wire harness to be diagnosed is -1, it indicates that the wire harness to be diagnosed is short-circuited, and the incident wave and the reflected wave have opposite polarities.

[0119] When the reflection coefficient of the wire harness to be diagnosed is -1 < ρ < 1, it indicates that the insulation of the wire harness to be diagnosed has wrinkles, wear, and other fault conditions. In this case, Z L ≠0, which means that the fault point is a series or parallel connection of inductors, capacitors and resistors.

[0120] In summary, based on the above analysis, it can be seen that when the wiring harness to be diagnosed experiences short-circuit and open-circuit faults, the reflected waveform and the impedance characteristics of the faulty wiring harness are obvious. The fault type can be directly determined through impedance testing, and the fault location can be determined through pulse return time. This application calculates the fault location and fault type of the faulty wiring harness using the time-domain reflection method, which differs from general designs. This application is based on an FPGA and uses a low-speed DA and RF transistor to build the pulse emission circuit, eliminating the need for expensive high-speed DA. At the signal acquisition end, through multi-phase data superposition, an equivalent 56GHz sampling frequency can be achieved using only a single 250kHz AD chip. The equivalent sampling frequency is not limited by the AD chip's operating frequency, and phase data alignment can be completed using a simple initialization circuit. This application features simplicity, high detection accuracy, and strong application scalability. It uses low test voltage and short pulse width, enabling convenient, accurate, and rapid aircraft wiring harness fault diagnosis without affecting airborne equipment.

[0121] In another embodiment, such as Figure 13 As shown, based on the same inventive concept as the foregoing embodiments, embodiments of this application also provide a wire harness fault diagnosis device, which includes:

[0122] The transmitting module is used to send diagnostic pulses to the wire harness to be diagnosed according to a preset amplitude.

[0123] A first obtaining module is configured to obtain a first time based on the diagnostic pulse; wherein, the first time is the time when the diagnostic pulse was sent;

[0124] The second acquisition module is used to receive reflected pulses returned from the fault point of the harness to be diagnosed;

[0125] The third obtaining module is used to obtain a second time based on the reflected pulse; wherein the second time is the time of receiving the transmitted pulse;

[0126] The fourth obtaining module is used to obtain the diagnostic location information of the wire harness to be diagnosed based on the first time and the second time.

[0127] It should be noted that each module in the wire harness fault diagnosis device in this embodiment corresponds one-to-one with each step in the wire harness fault diagnosis method in the aforementioned embodiment. Therefore, the specific implementation method and the technical effects achieved in this embodiment can be referred to the implementation method of the aforementioned wire harness fault diagnosis method, and will not be repeated here.

[0128] Furthermore, in one embodiment, this application also provides a computer device, the computer device including a processor, a memory, and a computer program stored in the memory, the computer program being executed by the processor to implement the methods in the foregoing embodiments.

[0129] In addition, in one embodiment, this application also provides a computer storage medium storing a computer program that is executed by a processor to implement the methods described in the foregoing embodiments.

[0130] In some embodiments, the computer-readable storage medium may be a memory such as FRAM, ROM, PROM, EPROM, EEPROM, flash memory, magnetic surface memory, optical disk, or CD-ROM; or it may be a device including one or any combination of the above-mentioned memories. The computer may be a variety of computing devices, including smart terminals and servers.

[0131] In some embodiments, executable instructions may take the form of a program, software, software module, script, or code, written in any form of programming language (including compiled or interpreted languages, or declarative or procedural languages), and may be deployed in any form, including as a standalone program or as a module, component, subroutine, or other unit suitable for use in a computing environment.

[0132] As an example, executable instructions may, but do not necessarily, correspond to files in a file system. They may be stored as part of a file that holds other programs or data, for example, in one or more scripts in a Hyper Text Markup Language (HTML) document, in a single file dedicated to the program in question, or in multiple collaborating files (e.g., a file that stores one or more modules, subroutines, or code sections).

[0133] As an example, executable instructions can be deployed to execute on a single computing device, or on multiple computing devices located in one location, or on multiple computing devices distributed across multiple locations and interconnected via a communication network.

[0134] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0135] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0136] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as read-only memory / random access memory, magnetic disk, optical disk) and includes several instructions to cause a multimedia terminal device (which may be a mobile phone, computer, television receiver, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0137] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A method for diagnosing wire harness faults, characterized in that, The method includes: A diagnostic pulse with a preset amplitude is sent to the wire harness under diagnosis. This pulse transmission is achieved through an FPGA and a pulse generation circuit. During pulse transmission, the FPGA controls the on / off state of the first and second RF transistors in the pulse generation circuit via an input interface, thereby controlling the pulse width and phase. The pulse amplitude is adjusted by a low-speed DA converter in the pulse generation circuit. The pulse is then sent to the wire harness under diagnosis via a third RF transistor and an output interface. The collector of the first RF transistor is connected to the low-speed DA converter's voltage output port, the base of the first RF transistor is connected to the FPGA, the emitter of the first RF transistor is connected to the collector of the second RF transistor, the base of the second RF transistor is connected to the FPGA, the emitter of the second RF transistor is grounded through a resistor, the base of the third RF transistor is connected to the emitter of the second RF transistor, and the collector of the third RF transistor is connected to the VCC port. The emitter of the third RF transistor is connected to the output interface, and the output interface is also connected to an initialization circuit. The initialization circuit includes a first initialization transistor, a second initialization transistor, and an initialization capacitor. The collector of the first initialization transistor is connected to the output interface, the base of the first initialization transistor is connected to the FPGA, the emitter of the first initialization transistor is connected to the collector of the second initialization transistor, the base of the second initialization transistor is connected to the FPGA, and the emitter of the second initialization transistor is grounded. The first end of the initialization capacitor is connected to the collector of the second initialization transistor, and the second end of the initialization capacitor is connected to the emitter of the second initialization transistor. The FPGA controls the first initialization transistor to turn on. After the FPGA shifts the pulse phase, it sends a pulse. After a single sampling is completed, the FPGA controls the second initialization transistor to turn on, discharging the charge of the initialization capacitor. Based on the diagnostic pulse, a first time is obtained; wherein, the first time is the time when the diagnostic pulse was sent; Receive reflected pulses returned from the fault point of the harness to be diagnosed; Based on the reflected pulse, a second time is obtained; wherein, the second time is the time of receiving the transmitted pulse; Based on the first time and the second time, the diagnostic location information of the wire harness to be diagnosed is obtained.

2. The wire harness fault diagnosis method as described in claim 1, characterized in that, Obtaining the second time based on the reflected pulse includes: Determine whether the received reflected pulses have reached a preset number of times; If the received reflected pulses reach the preset number of times, the reflected pulses of the preset number of times are aligned and sorted to obtain a second time.

3. The wire harness fault diagnosis method as described in claim 1, characterized in that, Sending diagnostic pulses to the harness to be diagnosed according to a preset amplitude includes: Based on the preset phase shift time, a diagnostic pulse is sent to the harness to be diagnosed according to the preset amplitude.

4. The wire harness fault diagnosis method as described in claim 1, characterized in that, The step of obtaining the diagnostic location information of the wire harness to be diagnosed based on the first time and the second time includes: A fault point model is constructed based on the pulse propagation speed in the harness to be diagnosed, the first time, and the second time. Based on the fault point model, the diagnostic location information of the harness to be diagnosed is obtained.

5. The wire harness fault diagnosis method as described in claim 4, characterized in that, The fault point model is constructed based on the pulse propagation speed in the harness to be diagnosed, the first time, and the second time, including: The fault point model is obtained using the following formula: Where L represents the location of the fault point. Indicates that immediately, Indicates the second time. Indicates the propagation speed of the pulse in the cable medium. Indicates the relative permeability of the cable medium. This indicates the relative permittivity of the cable. It represents the speed of light.

6. The wire harness fault diagnosis method as described in claim 1, characterized in that, After the step of obtaining the diagnostic location information of the harness to be diagnosed based on the first time and the second time, the method further includes: Obtain the load impedance and characteristic impedance of the fault point of the harness to be diagnosed; Based on the load impedance and the characteristic impedance, a reflection coefficient model of the wire harness to be diagnosed is constructed; Based on the reflection coefficient model, the fault type information of the harness to be diagnosed is obtained.

7. The wire harness fault diagnosis method as described in claim 6, characterized in that, The step of constructing the reflection coefficient model of the harness to be diagnosed based on the load impedance and the characteristic impedance includes: The reflection coefficient model of the wire harness to be diagnosed is constructed using the following formula: 。 in, This represents the reflection coefficient of the wire harness to be diagnosed. This indicates the load impedance at the fault point of the harness to be diagnosed. The characteristic impedance of the wire harness to be diagnosed is represented by , M represents the inductance of the wire harness to be diagnosed, and C represents the capacitance of the wire harness to be diagnosed.

8. The wire harness fault diagnosis method as described in claim 7, characterized in that, The process of obtaining fault type information for the harness to be diagnosed based on the reflection coefficient model includes: When the reflection coefficient ρ of the wire harness to be diagnosed is 0, the wire harness to be diagnosed is fault-free; When the reflection coefficient ρ of the wire harness to be diagnosed is 1, the wire harness to be diagnosed is open-circuited; When the reflection coefficient ρ of the wire harness to be diagnosed is -1, the wire harness to be diagnosed is short-circuited; When the reflection coefficient of the wire harness to be diagnosed is -1 < ρ < 1, the insulation of the wire harness to be diagnosed will wrinkle or wear.

9. A wire harness fault diagnosis device, characterized in that, The device includes: The transmitting module is used to send diagnostic pulses to the wire harness under diagnosis according to a preset amplitude. The transmission of the diagnostic pulses is implemented through an FPGA and a pulse generation circuit. When transmitting the diagnostic pulse, the FPGA controls the on / off state of the first and second RF transistors in the pulse generation circuit via an input interface, thereby controlling the width and phase of the generated pulse. The pulse amplitude is adjusted by a low-speed DA converter in the pulse generation circuit. The pulse is then transmitted to the wire harness under diagnosis via a third RF transistor and an output interface. The collector of the first RF transistor is connected to the low-speed DA converter's voltage output port, the base of the first RF transistor is connected to the FPGA, the emitter of the first RF transistor is connected to the collector of the second RF transistor, the base of the second RF transistor is connected to the FPGA, the emitter of the second RF transistor is grounded through a resistor, the base of the third RF transistor is connected to the emitter of the second RF transistor, and the collector of the third RF transistor is connected to the VCC port. The third RF transistor's emitter is connected to the output interface, and the output interface is also connected to an initialization circuit. The initialization circuit includes a first initialization transistor, a second initialization transistor, and an initialization capacitor. The collector of the first initialization transistor is connected to the output interface, the base of the first initialization transistor is connected to the FPGA, the emitter of the first initialization transistor is connected to the collector of the second initialization transistor, the base of the second initialization transistor is connected to the FPGA, and the emitter of the second initialization transistor is grounded. The first end of the initialization capacitor is connected to the collector of the second initialization transistor, and the second end of the initialization capacitor is connected to the emitter of the second initialization transistor. The FPGA controls the first initialization transistor to turn on. After the FPGA shifts the pulse phase, it sends a pulse. After a single sampling is completed, the FPGA controls the second initialization transistor to turn on, discharging the charge of the initialization capacitor. A first obtaining module is configured to obtain a first time based on the diagnostic pulse; wherein, the first time is the time when the diagnostic pulse was sent; The second acquisition module is used to receive reflected pulses returned from the fault point of the harness to be diagnosed; The third obtaining module is used to obtain a second time based on the reflected pulse; wherein the second time is the time of receiving the transmitted pulse; The fourth obtaining module is used to obtain the diagnostic location information of the wire harness to be diagnosed based on the first time and the second time.

10. A computer device, characterized in that, The computer device includes a memory and a processor, wherein the memory stores a computer program and the processor executes the computer program to implement the method as described in any one of claims 1-8.

11. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, and the processor executes the computer program to implement the method as described in any one of claims 1-8.

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