A fixed-wing aircraft brake system rapid fault diagnosis method

Abstract

This invention discloses a rapid fault diagnosis method for a fixed-wing aircraft braking system, comprising: Step 1, during the entire braking process, executing primary and backup channel command-response verification, and judging the effectiveness of the braking system feedback signal response; Step 2, if the primary and backup channel command-response verification passes, verifying the power effectiveness of the braking mechanism by acquiring the braking mechanism current value; Step 3, after confirming the power effectiveness and landing, verifying the braking effect and the consistency of left and right braking output by acquiring the aircraft's yaw acceleration data and yaw angle deviation. This invention solves the problems of existing fault diagnosis methods for aircraft braking systems, which can only determine whether a braking command has been issued or whether the motor has entered a stall state, resulting in the inability to detect braking performance degradation, susceptibility to environmental interference, and poor fault isolation capabilities.

Description

Technical Field

[0001] This invention relates to, but is not limited to, the field of aircraft technology, and in particular to a method for rapid fault diagnosis of a fixed-wing aircraft braking system. Background Technology

[0002] The braking system of a fixed-wing aircraft consists of a controller, motor, actuators, and brake pads. The controller drives the motor to press the brake discs on the wheels to achieve braking, enabling ground deceleration, differential braking, and static braking at the takeoff line. Since the reliability of the aircraft's braking system directly affects landing safety and takeoff distance, fault diagnosis is crucial. Rapid fault location is directly related to the pilot's emergency response measures, ensuring the aircraft remains controllable.

[0003] In existing technologies, fault diagnosis of aircraft braking systems generally only detects at the product level or system communication level, that is, it can only determine whether a braking command has been issued or whether the motor has entered a stall state. Summary of the Invention

[0004] The purpose of this invention is to provide a rapid fault diagnosis method for the braking system of a fixed-wing aircraft, so as to solve the problems of existing fault diagnosis methods for aircraft braking systems, which can only determine whether a braking command has been issued or whether the motor has entered a stall state, thus failing to detect brake performance degradation, being susceptible to environmental interference, and having poor fault isolation capabilities.

[0005] The technical solution of the present invention is as follows: The present invention provides a method for rapid fault diagnosis of a fixed-wing aircraft braking system, including: Step 1, during the entire braking process, executing the main and backup channel command-response verification, and judging the effectiveness of the braking system feedback signal response; Step 2: If the main and backup channel command-response verifications pass, verify the power effectiveness of the braking mechanism by obtaining the braking mechanism current value; Step 3: After confirming that the power is effective and the aircraft has landed, the braking effect and consistency of left and right braking output are verified by acquiring the aircraft's heading acceleration data and heading angle deviation.

[0006] Optionally, the rapid fault diagnosis method for the braking system of a fixed-wing aircraft as described above specifically includes: S1, Braking System Main Channel Command-Response Verification Phase: Before approach and landing, the flight control system sends a braking control command to the main channel, starts the first timer T1, and simultaneously monitors the feedback signal of the braking actuator; if a braking feedback signal is received before T1 expires, the command-response link is determined to be normal, and S3 is executed; if no feedback signal is received after T1 expires, "Main channel braking mechanism no response fault" is immediately reported, and S2 is executed; S2, Braking System Backup Channel Command-Response Verification: The flight control system sends a backup channel braking control command to the backup channel, starts the second timer T2, and simultaneously monitors the feedback signal of the braking actuator; if a braking feedback signal is received before T2 expires, the backup channel command-response link is determined to be normal, and proceeds to S3; if no feedback signal is received after T2 expires, "Brake mechanism no response fault" is immediately reported, and the detection process is terminated; S3, Power Effectiveness Verification Stage: After confirming that the actuator has responded, the third timer T3 is started, and the monitoring parameters used to reflect the braking power are monitored. If the monitoring parameters meet the preset conditions within T3 time, the power output is determined to be effective, the brake is released and S4 is executed. If the monitoring parameters do not meet the preset conditions within T3 time, the brake is released and the detection process is terminated. S4, Braking Effect Verification Phase: After confirming effective power output and successful landing, the flight control system issues a braking control command, delayed for a preset time. T delay Then, the fourth timer T4 is started to monitor the heading acceleration data from the inertial measurement unit (IMU), and the average value of the heading acceleration data is continuously calculated within time T4. If the absolute value of the average heading acceleration calculated within time T4 is greater than or equal to a preset acceleration threshold... A min If the braking effect is normal, proceed to step S5; if the absolute value of the average heading acceleration calculated within time T4 is consistently less than the preset acceleration threshold... A min If the error occurs, a "low braking efficiency fault" will be reported, and the testing process will be terminated. S5, Verification of Consistency of Left and Right Braking Force Output: After confirming normal braking performance, start the fifth timer T5 and monitor the aircraft's heading angle from the inertial navigation system; during time T5, continuously calculate the heading angle deviation between the aircraft's heading angle and the target heading angle; if the absolute value of the heading angle deviation during time T5 is always less than the preset deviation threshold Δ... φ min If the brake output consistency is normal, then the brakes are considered to be functioning correctly this time; if the absolute value of the heading angle deviation within time T5 is greater than or equal to Δ... φ min If the error occurs, the system will report a "fault of asymmetrical braking force between the left and right sides".

[0007] Optionally, in the fast fault diagnosis method for the braking system of a fixed-wing aircraft as described above, the braking command sent by the flight control system to the main channel in S1 is a digital command. In S2, the flight control system sends an analog control command to the backup channel, and the received braking feedback signal is an analog voltage value. If the analog voltage value is increasing, it is determined that the backup channel command-response link is normal.

[0008] Optionally, in the rapid fault diagnosis method for the braking system of a fixed-wing aircraft as described above, the monitoring parameter used to reflect the braking force in S3 is: motor current; If the current value continues to exceed the preset current threshold within time T3. I min If so, the power output is deemed valid, and the system enters S4; If the current value remains below the preset current threshold throughout time T3. I min If the error occurs, a "power output insufficient fault" will be reported, and the testing process will be terminated. Wherein, the preset current threshold I min It is greater than the idle current and less than the maximum operating current.

[0009] Optionally, in the fast fault diagnosis method for the fixed-wing aircraft braking system described above, the monitoring parameter monitored in S3 that reflects the braking force is: the brake pressure feedback value. If the brake pressure feedback value is continuously greater than or equal to the minimum brake pressure value given by the flight controller pressure command during time T3, the power output is deemed valid and the process proceeds to S4. If the brake pressure feedback value is consistently less than the minimum brake pressure value given by the flight controller within time T3, an "insufficient power output fault" will be reported, and the detection process will be terminated. The minimum pressure value of the given pressure command is the minimum value within the brake pressure error range.

[0010] Optionally, in the rapid fault diagnosis method for the braking system of a fixed-wing aircraft as described above, The preset acceleration threshold in S4 A min It can be dynamically adjusted according to the ground conditions of the aircraft landing runway; In S4, the phase judgment of S4 is only activated after the altitude sensor detects that the aircraft has been fully grounded. Before reporting a "low braking performance fault", S4 queries the aircraft's attitude information. If the aircraft has a significant pitch angle, it assumes that the runway has a slope and downgrades the fault alarm.

[0011] Optionally, in the rapid fault diagnosis method for the braking system of a fixed-wing aircraft as described above, step S5 further includes: If the heading angle deviation within time T5 exceeds the deviation limit Δ φ limit Then stop immediately.

[0012] Optionally, in the rapid fault diagnosis method for the braking system of a fixed-wing aircraft as described above, before performing the judgment in step S5, it is required to determine that the absolute value of the heading angle deviation is less than a preset initial deviation value Δ. φ init .

[0013] Optionally, in the rapid fault diagnosis method for the fixed-wing aircraft braking system described above, during the entire process of the consistency verification stage of left and right braking force output in S5, it is required to ensure that the left and right braking quantity command values ​​are the same in the previous cycle.

[0014] Optionally, in the fast fault diagnosis method for the fixed-wing aircraft braking system described above, after the T5 time in S5 ends, the heading correction control is restored.

[0015] The beneficial effects of this invention are as follows: This invention provides a rapid fault diagnosis method for a fixed-wing aircraft braking system. During the entire braking process, primary and backup channel command-response verification is performed, and the effectiveness of the braking system's feedback signal response is judged. If the primary and backup channel command-response verification passes, the braking mechanism's power effectiveness is verified by acquiring the braking mechanism's current value. After confirming power effectiveness and landing, the braking effect and consistency of left and right braking outputs are verified by acquiring the aircraft's yaw acceleration data and yaw angle deviation. The rapid fault diagnosis method provided by this invention has the following beneficial effects: First, it is simple to calculate and highly efficient: it does not require complex model training and a large amount of data processing, and it is easy to implement on a low-computing-power flight control motherboard microcontroller. Through a multi-level logic judgment process, it can quickly locate faults and effectively improve the accuracy and comprehensiveness of fault detection.

[0016] Second, fault location is clear: through a phased and sequential detection logic, faults can be initially located in five different stages: "main channel command response", "standby channel command response", "power output", "mechanical efficiency" and "output consistency", which improves maintainability.

[0017] Third, high reliability: By setting reasonable timers and physical thresholds, false alarms caused by environmental disturbances can be effectively avoided, making the detection results more reliable.

[0018] Fourth, low cost: It does not require the addition of expensive sensors or computing units, and can be achieved using the existing sensors on the aircraft, making it easy to promote. Attached Figure Description

[0019] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of the present invention and do not constitute a limitation on the technical solutions of the present invention.

[0020] Figure 1 A flow diagram illustrating a rapid fault diagnosis method for a fixed-wing aircraft braking system provided in an embodiment of the present invention; Figure 2 Another schematic diagram of a rapid fault diagnosis method for a fixed-wing aircraft braking system provided in an embodiment of the present invention; Figure 3 This is a schematic diagram illustrating the principle of heading deviation in the rapid fault diagnosis method for the braking system of a fixed-wing aircraft provided in an embodiment of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

[0022] As explained in the background section, fault diagnosis of aircraft braking systems typically only detects issues at the product level or system communication level; that is, it can only determine whether a braking command has been issued or whether the motor has entered a stall state. The above methods have the following significant drawbacks: 1. Unable to detect brake performance degradation: It cannot identify faults that reduce braking efficiency, such as brake pad wear and decreased brake servo torque.

[0023] 2. Susceptible to environmental interference: When landing on tilted or uneven ground, the vibration and attitude changes of the aircraft itself may be misinterpreted as brake malfunction.

[0024] 3. Poor fault isolation capability: It is impossible to accurately locate whether the fault originates from a power supply module failure, communication failure, actuator failure, or mechanical jamming.

[0025] To address the aforementioned problems, this invention proposes a rapid fault diagnosis method for the braking system of fixed-wing aircraft. The method features a clear and simple judgment logic, low computational load, and no need for complex algorithms. By designing a multi-level logical judgment process based on time series and physical thresholds, this method enables rapid and reliable fault location for monitoring common states, effectively improving the accuracy and comprehensiveness of fault detection.

[0026] The present invention provides the following specific embodiments, which can be combined with each other. For the same or similar concepts or processes, they may not be described again in some embodiments.

[0027] like Figure 1 As shown in the flowchart, this invention provides a rapid fault diagnosis method for a fixed-wing aircraft braking system, comprising the following steps: Step 1: During the entire braking process, execute the main and backup channel commands and response verification, and judge the effectiveness of the braking system feedback signal response. Step 2: If the main and backup channel command-response verifications pass, verify the power effectiveness of the braking mechanism by obtaining the braking mechanism current value; Step 3: After confirming that the power is effective and the aircraft has landed, the braking effect and consistency of left and right braking output are verified by acquiring the aircraft's heading acceleration data and heading angle deviation.

[0028] The following combination Figure 2 and Figure 3 The present invention provides an illustrative description of a specific implementation scheme for a rapid fault diagnosis method for a fixed-wing aircraft braking system.

[0029] like Figure 2 As shown, the rapid fault diagnosis method for the braking system of a fixed-wing aircraft provided by the present invention includes the following steps performed in sequence: S1: Braking System Main Channel Command-Response Verification Phase: Before approach and landing, the flight control system sends braking control commands to the main channel, starts the first timer T1 (e.g., duration 1000ms), and simultaneously monitors the feedback signals of the braking actuators (such as servos or ESCs). If a feedback signal (such as the servo angle starting to change or the motor current starting to rise) is received before the T1 timeout, the command-response link is determined to be normal, and the process enters S3. If no feedback signal is received after T1 timeout, "Main channel brake mechanism unresponsive fault" will be reported immediately, and the process will proceed to S2.

[0030] S2: Braking System Backup Channel Command - Response Verification: The flight control system sends a backup channel braking control command (analog signal) to the backup channel, starts the second timer T2 (e.g., duration 1000ms), and simultaneously monitors the feedback signal of the braking actuator; If a braking feedback signal (analog voltage rise) is received before the T2 timeout, the backup channel command-response link is determined to be normal, and the process proceeds to S3. If no feedback signal is received after T2 timeout, "Brake mechanism unresponsive fault" will be reported immediately, and the subsequent testing process will be terminated.

[0031] It should be noted that the S2 stage judgment is only activated if the braking system has a backup channel and the main channel actuator does not respond.

[0032] S3: Power effectiveness verification stage: After confirming that the actuator has a response, start the third timer T3 (e.g., duration 500ms) and monitor the core parameters that reflect the braking power (such as motor current). If the current value continues to exceed a preset current threshold during time T3. I min(If the threshold is greater than the idle current but less than the maximum operating current), then the power output is deemed valid, the brake is released, and the process enters S4. If the current value remains below this value throughout time T3... I min If the error occurs, a "power output insufficient fault" will be reported (possible causes include circuit break, servo motor damage, power supply problem, etc.), the brake will be released and the subsequent testing process will be terminated.

[0033] S4: Braking effect verification phase: After confirming effective power output and landing, the flight control system issues braking control commands, with a delay of a certain period of time. T delay (e.g., 500ms, to ensure the brakes have started to work), then start the fourth timer T4 (e.g., 3000ms), and monitor the heading acceleration data from the inertial measurement unit (IMU); and continuously calculate the average value of the heading acceleration data during the T4 time period; If the absolute value of the average heading acceleration calculated within time T4 is greater than or equal to a preset acceleration threshold A min If the braking effect is normal, proceed to S5. If the absolute value of the average heading acceleration calculated within time T4 is always less than the preset acceleration threshold A min If the error occurs, a "low braking performance fault" will be reported (possible causes include worn brake pads, slippery ground, etc.), and the subsequent testing process will be terminated.

[0034] It should be noted that the preset acceleration threshold A min It can be dynamically adjusted according to the ground conditions of the landing runway; the S4 stage judgment is only activated after the altitude sensor detects that the aircraft has fully touched down, in order to avoid accidentally triggering the braking performance failure in the air.

[0035] In practice, before reporting a "low braking efficiency fault", the aircraft's attitude information is checked. If the aircraft has a significant pitch angle, it is assumed that the runway has a slope, and the fault alarm is downgraded to avoid misjudgment caused by slope interference.

[0036] S5: Verification of consistency of left and right braking force output: After confirming that the braking performance is normal, start the fifth timer T5 (e.g., duration 3000ms) and monitor the body heading angle from the inertial navigation system; during the T5 time period, continuously calculate the deviation between the body heading angle and the target heading angle; If the absolute value of the heading angle deviation within time T5 is always less than the preset deviation threshold Δ φ min If so, it is determined that the brake output consistency is normal and there is no brake malfunction in this case; If the absolute value of the heading angle deviation within time T5 is greater than or equal to Δ φ min If the error exceeds the deviation limit Δ, a "misalignment of left and right braking force" fault will be reported (possible causes include wear on one side of the brake pads, large output error of the brake force sensor, etc.). φ limit It needs to be stopped immediately.

[0037] Furthermore, before activating the S5 judgment, it must be ensured that the absolute value of the heading angle deviation is less than the preset initial deviation value Δ. φ init ; Furthermore, during the entire process of verifying the consistency of left and right braking force output in S5, it is required to ensure that no correction control commands are used and that the left and right braking quantity command setpoints are the same.

[0038] Furthermore, after T5 time has ended, heading correction control should be restored.

[0039] It should be noted that, as Figure 3 As shown, after the aircraft lands, due to landing deviation, it is necessary to use correction control to maintain the heading deviation at Δ. φ init Within this range, the course correction control is disconnected and the same braking value is applied. Timer T5 is started. During time T5, the heading deviation continues to increase beyond the preset minimum heading deviation value Δ. φ min If the heading deviation exceeds the preset critical heading deviation value Δ within time T5, it is determined as a "fault of asymmetrical braking force between the left and right sides". φ limit It needs to be stopped immediately.

[0040] This invention provides a rapid fault diagnosis method for a fixed-wing aircraft braking system. During the entire braking process, primary and backup channel command-response verification is performed, and the effectiveness of the braking system's feedback signal response is judged. If the primary and backup channel command-response verification passes, the braking mechanism's power effectiveness is verified by acquiring the braking mechanism's current value. After confirming power effectiveness and successful landing, the braking effect and consistency of left and right braking output are verified by acquiring the aircraft's yaw acceleration data and yaw angle deviation. The rapid fault diagnosis method provided by this invention has the following beneficial effects: First, it is simple to calculate and highly efficient: it does not require complex model training and a large amount of data processing, and it is easy to implement on a low-computing-power flight control motherboard microcontroller. Through a multi-level logic judgment process, it can quickly locate faults and effectively improve the accuracy and comprehensiveness of fault detection.

[0041] Second, fault location is clear: through a phased and sequential detection logic, faults can be initially located in five different stages: "main channel command response", "standby channel command response", "power output", "mechanical efficiency" and "output consistency", which improves maintainability.

[0042] Third, high reliability: By setting reasonable timers and physical thresholds, false alarms caused by environmental disturbances can be effectively avoided, making the detection results more reliable.

[0043] Fourth, low cost: It does not require the addition of expensive sensors or computing units, and can be achieved using the existing sensors on the aircraft, making it easy to promote.

[0044] The following example, using a fixed-wing aircraft employing dual-channel motor friction braking as its braking method, illustrates the implementation scheme of the rapid fault diagnosis method for the braking system of a fixed-wing aircraft provided by this invention.

[0045] Step 1, S1 Phase: The aircraft approaches and lands, and the flight control system issues a main channel braking command. The system starts a 1000ms timer T1 and monitors the feedback braking pressure data. If a braking pressure feedback signal is received after 500ms, S1 is considered successful, and the system proceeds to S3; otherwise, it proceeds to S2.

[0046] Step 2, S2 phase: The flight control system sends a backup channel control command (analog signal) to start the second timer T2 (e.g., duration 1000ms) and simultaneously monitors the feedback signal of the brake actuator; Step 3, S3 phase: Start 500ms timer T3. Monitor motor current value and set threshold. I min The current is 0.5A (idle current is 0.1A). If the current is continuously above 0.5A within the monitoring time, the power output is deemed valid, S3 is passed, the brakes are released, and the aircraft waits for grounding before entering S4.

[0047] Step 4, S4 Phase: After the flight control system determines that the aircraft has touched down, the engines switch to idle speed and execute the braking command. Then, a 3000ms timer T4 is started. The average deceleration along the x-axis (heading) during these 3000ms is calculated. A threshold is set. A min The average deceleration is 1.5 m / s². If the calculated average deceleration is only -0.8 m / s² (the absolute value is less than the threshold), it is determined whether there is a significant change in the pitch angle. If not, the system will finally determine and report "low braking performance fault", which may be due to brake motor performance degradation, brake pad wear, slippery ground, etc., and terminate the process; if the braking performance is determined to be acceptable, it will enter the S5 stage.

[0048] Step 5, S5 phase: The flight control system continuously calculates the deviation of the aircraft's heading from the runway target's heading, and sets an initial deviation value Δ. φ init The deviation threshold is 0.5°. φ min The deviation limit is 1.0°, Δ φ limit The initial heading angle is 3°. Correction is used to ensure the absolute value of the heading deviation is not less than the initial value of 0.5°. A 3000ms timer is started. During this time, in the previous loop, the left and right braking commands are given the same value. Within 3000ms, the deviation between the heading angle and the target heading is continuously calculated. If the absolute value of this heading angle deviation is always less than the preset deviation threshold of 1.0°, the braking effect is considered normal, and there is no braking fault in this instance. If the absolute value exceeds 1.0°, "Asymmetrical braking force" is reported. Possible causes include wear on one side of the brake pads or a large output error of the force sensor on one side of the brake mechanism. Correction is then resumed. If the deviation exceeds the limit of 3.0°, immediate braking is required.

[0049] While the embodiments disclosed in this invention are as described above, they are merely illustrative of the embodiments to facilitate understanding of the invention and are not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and variations in the form and details of the implementation without departing from the spirit and scope disclosed herein; however, the scope of patent protection for this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A method for rapid fault diagnosis of a fixed-wing aircraft braking system, characterized in that, include: Step 1: During the entire braking process, execute the main and backup channel commands and response verification, and judge the effectiveness of the braking system feedback signal response. Step 2: If the main and backup channel command-response verifications pass, verify the power effectiveness of the braking mechanism by obtaining the braking mechanism current value; Step 3: After confirming that the power is effective and the aircraft has landed, the braking effect and consistency of left and right braking output are verified by acquiring the aircraft's yaw acceleration data and yaw angle deviation. Specifically, it includes: S1, Braking System Main Channel Command-Response Verification Phase: Before approach and landing, after the flight control system sends the braking control command to the main channel, the first timer T1 is started, and the feedback signal of the braking actuator is monitored at the same time; if the braking feedback signal is received before T1 expires, the command-response link is determined to be normal, and S3 is executed; if no feedback signal is received after T1 expires, "Main channel braking mechanism no response fault" is immediately reported, and S2 is executed; S2, Braking System Backup Channel Command-Response Verification: The flight control system sends a backup channel control command to the backup channel, starts the second timer T2, and simultaneously monitors the feedback signal of the braking actuator; if a braking feedback signal is received before T2 expires, the backup channel command-response link is determined to be normal, and the process proceeds to S3; if no feedback signal is received after T2 expires, "Brake mechanism no response fault" is immediately reported, and the detection process is terminated. S3, Power Effectiveness Verification Stage: After confirming that the actuator has responded, the third timer T3 is started, and the monitoring parameters used to reflect the braking power are monitored. If the monitoring parameters meet the preset conditions within T3 time, the power output is determined to be effective, the brake is released and S4 is executed. If the monitoring parameters do not meet the preset conditions within T3 time, the brake is released and the detection process is terminated. S4, Braking Effect Verification Phase: After confirming effective power output and successful landing, the flight control system issues a braking control command, delayed for a preset time. T delay Then, the fourth timer T4 is started to monitor the heading acceleration data from the inertial measurement unit (IMU), and the average value of the heading acceleration data is continuously calculated within the time period T4. If the absolute value of the average heading acceleration calculated within the time period T4 is greater than or equal to a preset acceleration threshold... A min If the braking effect is normal, proceed to step S5; if the absolute value of the average heading acceleration calculated within time T4 is consistently less than the preset acceleration threshold... A min If the error occurs, a "low braking performance fault" will be reported, and the testing process will be terminated. S5, Verification of Consistency of Left and Right Braking Force Output: After confirming normal braking performance, start the fifth timer T5 and monitor the aircraft's heading angle from the inertial navigation system; during time T5, continuously calculate the heading angle deviation between the aircraft's heading angle and the target heading angle; if the absolute value of the heading angle deviation during time T5 is always less than the preset deviation threshold Δ... φ min If the brake output consistency is normal, then the brakes are considered to be functioning correctly this time; if the absolute value of the heading angle deviation within time T5 is greater than or equal to Δ... φ min If the error occurs, the system will report a "fault of asymmetrical braking force between the left and right sides".

2. The rapid fault diagnosis method for the braking system of a fixed-wing aircraft according to claim 1, characterized in that, The braking control command sent by the flight control system to the main channel in S1 is a digital command. In S2, the flight control system sends an analog control command to the backup channel, and the received braking feedback signal is an analog voltage value. If the analog voltage value is increasing, it is determined that the backup channel command-response link is normal.

3. The rapid fault diagnosis method for the braking system of a fixed-wing aircraft according to claim 1, characterized in that, The monitoring parameter used in S3 to reflect braking force is the motor current value; If the current value continues to exceed the preset current threshold within time T3. I min If so, the power output is deemed valid, and the system enters S4; If the current value remains below the preset current threshold throughout time T3. I min If the error occurs, a "power output insufficient fault" will be reported, and the testing process will be terminated. Wherein, the preset current threshold I min It is greater than the idle current and less than the maximum operating current.

4. The rapid fault diagnosis method for the braking system of a fixed-wing aircraft according to claim 1, characterized in that, The monitoring parameter used in S3 to reflect braking force is the brake pressure feedback value; If the brake pressure feedback value is continuously greater than or equal to the minimum brake pressure value given by the flight controller pressure command during time T3, the power output is deemed valid and the process proceeds to S4. If the brake pressure feedback value is consistently less than the minimum brake pressure value given by the flight controller within time T3, an "insufficient power output fault" will be reported, and the detection process will be terminated. The minimum pressure value of the given pressure command is the minimum value within the brake pressure error range.

5. The rapid fault diagnosis method for the braking system of a fixed-wing aircraft according to claim 1, characterized in that, The preset acceleration threshold in S4 A min It can be dynamically adjusted according to the ground conditions of the aircraft landing runway; In S4, the phase judgment of S4 is only activated after the altitude sensor detects that the aircraft has been fully grounded. Before reporting a "low braking performance fault", S4 queries the aircraft's attitude information. If the aircraft has a significant pitch angle, it assumes that the runway has a slope and downgrades the fault alarm.

6. The rapid fault diagnosis method for the braking system of a fixed-wing aircraft according to claim 1, characterized in that, The S5 also includes: If the heading angle deviation within time T5 exceeds the deviation limit Δ φ limit Then stop immediately.

7. The rapid fault diagnosis method for the braking system of a fixed-wing aircraft according to claim 1, characterized in that, Before performing the judgment in step S5, it is required that the absolute value of the heading angle deviation is less than the preset initial deviation value Δ. φ init .

8. The rapid fault diagnosis method for the braking system of a fixed-wing aircraft according to claim 1, characterized in that, Throughout the entire process of verifying the consistency of left and right braking force output in S5, it is required to ensure that the left and right braking quantity command values ​​are the same during the front wheel cycle.

9. The rapid fault diagnosis method for the braking system of a fixed-wing aircraft according to claim 1, characterized in that, After time T5 in S5 ends, heading correction control is resumed.

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