A method and apparatus for aircraft control surface actuation system line leak detection and mitigation

Abstract

The present application relates to the technical field of aircraft system fault diagnosis, and proposes a method and device for detecting and disposing pipeline leakage of aircraft control surface operating system. The method comprises: obtaining working data of each control surface; obtaining control surface actuator position values at different positions of the control surface deflection at different flight speeds according to the control surface actuator position signal, calculating the actuator motion speed V1, and obtaining the control surface actuator supply pressure pipeline flow rate monitoring model according to V1; calculating the supply pressure pipeline hydraulic oil flow rate through the flow rate model and comparing it with the actual flow rate; determining whether the control surface actuator supply pressure pipeline has leakage according to the comparison result; and disposing the fault after determining the pipeline leakage fault. The present application makes up for the lack of pipeline leakage fault detection means of the control surface operating system at the present stage, is simple to implement, easy to modify in the field, realizes the detection of the supply pressure pipeline leakage fault which endangers flight safety, and can effectively guarantee flight safety.

Description

Technical Field

[0001] This invention relates to the field of aircraft system fault diagnosis technology, and in particular to a method and apparatus for detecting and handling leaks in the piping of an aircraft control surface system. Background Technology

[0002] The control surface system is a crucial component of an aircraft's flight control system. It primarily consists of control surface actuators and their primary and backup pressurization lines, typically housed within the main wing surfaces (such as the wing and vertical stabilizer). It receives commands from the flight control computer and, based on these commands, uses high-pressure hydraulic oil supplied through the pressurization lines to control and drive the actuators, thereby deflecting the corresponding control surfaces and achieving the desired changes in the aircraft's flight attitude. A malfunction in the control surface system can range from reducing control efficiency and affecting aircraft handling to, in severe cases, endangering flight safety and causing serious accidents.

[0003] Currently, aircraft systems have relatively comprehensive methods for detecting and handling control surface actuator malfunctions. However, there is a general lack of methods for detecting and addressing leaks in the pressurization lines, preventing timely detection of such leaks. Furthermore, since the pressurization lines are primarily located within the wings and vertical stabilizer, they are prone to damage and breakage in the event of accidental disruption. This can lead to the complete loss of hydraulic oil from single or dual hydraulic tanks, causing some or all of the aircraft's control surfaces to lose their drive source, reducing controllability by half or even completely, resulting in loss of control and a crash.

[0004] Therefore, leaks in the pressure supply lines pose a greater risk, and there have been incidents where leaks in the main and backup pressure supply lines have led to aircraft crashes due to loss of control. Summary of the Invention

[0005] Technical issues:

[0006] When the pressure supply lines of an aircraft control surface are damaged by accident, they are prone to breakage or fracture, resulting in the complete leakage of hydraulic oil from a single or dual hydraulic oil tank. This causes some or all of the aircraft's control surfaces to lose their drive source, reducing the controllability by half or even completely, leading to the aircraft going out of control and crashing.

[0007] Objective of this invention:

[0008] This invention provides a method for detecting leaks in the piping of an aircraft control surface system, enabling the aircraft system to promptly detect leaks in the control surface pressure supply piping and take corrective measures to prevent further hydraulic oil leakage and avoid serious consequences.

[0009] Technical solution of the present invention:

[0010] Currently, most aircraft hydraulic pumps are constant-pressure variable-flow pumps. Analyzing the operating data of control surface actuators, the hydraulic oil flow rate in their pressure supply lines directly affects the actuator's movement speed, and follows a certain nonlinear relationship. Combining this with other key factors influencing actuator speed, such as flight speed and control surface position, a hydraulic oil flow rate model for the pressure supply lines is established using existing operating data. This model is then compared with actual flow rate samples to determine if leaks exist in the pressure supply lines. Finally, a hydraulic oil tank level alarm signal is introduced to further confirm the existence of a leak, allowing the aircraft system to decide whether to shut off the leaking line.

[0011] On the one hand, this invention proposes a method for detecting and handling leaks in the piping of an aircraft control surface system, which includes the following steps:

[0012] Step 1. Obtain the no-load operating data of each control surface actuator from the factory data, including control surface position, actuator position, and hydraulic oil flow rate and velocity data; obtain the flight speed, actuator position, and hydraulic oil flow rate and velocity data of control surface deflection at different positions under various typical flight profiles from the flight data. After removing outliers, the above data will be used as modeling data.

[0013] Step 2. Obtain the hydraulic oil flow velocity in the aileron pressurization line based on the flow velocity sensor; obtain the aileron actuator position value at different flight speeds and when the aileron control surface is deflected at different positions, based on the control surface actuator position signal (LVDT); calculate the ratio of the difference in control surface actuator position change to time at 100ms intervals to obtain the actuator speed; based on the known hydraulic oil flow velocity and actuator speed data in the pressurization line, perform quadratic polynomial fitting using the least squares method to obtain the functional relationship, which serves as the flow velocity monitoring model.

[0014] Step 3. The flight control computer collects actuator motion speed data, calculates the hydraulic oil flow rate in the pressure supply line using a flow rate model, and compares the calculated value with the actual sampled value from the flow rate sensor. A monitoring threshold of 2% is set for a duration of 300ms; a difference exceeding 2% of the calculated value satisfies the leakage fault determination condition.

[0015] Step 4. Introduce the dual-level alarm signals from the relevant hydraulic tanks for final judgment and control output. If both of the following conditions are met simultaneously and last for 300ms, the flight control computer determines that there is a leak in the pressure supply line of the control surface actuator.

[0016] 1) |Calculated flow velocity - Actual sampled value| > 2% * Calculated flow velocity

[0017] 2) The relevant hydraulic oil tank dual-level alarm signal persists.

[0018] After a leak is detected, the flight control computer issues a control command to close the pressure supply pipe shut-off valve, cut off the fuel supply, and drive the control surface actuators to work via the backup pressure supply pipe.

[0019] On the other hand, this invention proposes a device for detecting and handling leaks in the piping of an aircraft control surface system. This device includes: a data acquisition module, a data processing module, and a control output module. Wherein:

[0020] The data acquisition module is used to obtain the working data of each control surface under no-load conditions from the aircraft ground test data; and to obtain the working data of each control surface from the aircraft flight data.

[0021] The data processing module is used to obtain the position values ​​of the control surface actuator cylinder at different flight speeds based on the control surface actuator cylinder position signal, calculate the actuator cylinder movement speed V1, and obtain the flow velocity monitoring model of the control surface actuator pressure supply line based on V1; calculate the hydraulic oil flow velocity of the pressure supply line through the flow velocity model, compare the calculated flow velocity value with the actual sampled flow velocity value; set up fault judgment logic to determine whether there is a leak in the control surface actuator pressure supply line based on the comparison result of the calculated flow velocity value and the actual sampled flow velocity value;

[0022] The control output module is used to handle pipeline leaks and other faults.

[0023] Advantages of this invention:

[0024] This invention provides a method for detecting leakage faults in the pressure supply lines of aircraft control surface actuators, filling the gap in current methods for detecting leakage faults in control surface system pipelines. It is simple to implement, with relevant parameter data readily available and fitting easily achieved. Field modifications are simple, requiring only the addition of a flow velocity sensor and dual liquid level alarms, and only minor adjustments to the wiring, making modification easy. It enables the detection of leakage faults in pressure supply lines that endanger flight safety, effectively ensuring flight safety. Attached Figure Description

[0025] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a simplified diagram illustrating the principle of leak detection and handling in the pressure supply pipeline of an airfoil control surface actuator according to an embodiment of the present invention;

[0027] Figure 2 This is a flowchart illustrating the detection and handling of leaks in the pressure supply line of the aileron control surface actuator according to an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the fitting curves of the oil inlet velocity and motion velocity of the control surface actuator at different flight speeds when the control surface aileron is in a certain position, according to an embodiment of the present invention.

[0029] Figure 4 This is a schematic diagram of a leak detection method for the pressure supply line of a rudder actuator according to an embodiment of the present invention. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] The features and illustrative embodiments of various aspects of the present invention will now be described in detail. Numerous specific details are set forth in the following detailed description to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention. The invention is by no means limited to any specific setups and methods set forth below, but covers any improvements, substitutions, and modifications to structures, methods, and devices without departing from the spirit of the invention. Well-known structures and techniques are not shown in the drawings and the following description to avoid unnecessarily obscuring the invention.

[0032] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other, and the various embodiments can be referenced and cited in each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0033] Appendix Figure 1 This is a simplified diagram illustrating the principle of leak detection and handling in the pressure supply line of the aircraft aileron control surface actuator.

[0034] refer to Figure 1Based on the design characteristics of currently in-service aircraft, the aileron control surface actuators and their pressurization lines are located within the main wing structure. Flow velocity sensors and line shut-off valves are installed on the aileron control surface pressurization lines in the fuselage-to-main wing interface area. A dual-level warning system is installed in the hydraulic oil tank, incorporating the control surface actuator position (LVDT) signal collected by the flight control computer. The flow velocity sensor measures the hydraulic oil flow velocity in the pressurization lines. The dual-level warning system contains two floats; when the hydraulic oil level drops to two different heights, the floats fall, continuously activating the warning signal. Its function is to issue a reliable warning signal when the hydraulic oil level continues to decrease. The height difference Δh between the two floats can be designed according to actual needs (recommended value is 5% * hydraulic level height). The line shut-off valve is used to cut off the line in case of hydraulic oil leakage. The control surface actuator position data is used to calculate the control surface actuator movement speed.

[0035] Appendix Figure 2 This is a flowchart for detecting and handling leaks in the pressure supply lines of the aileron control surface actuators. (Attached) Figure 3 It is a curve showing the fitting relationship between the oil inlet velocity and the motion velocity of the control surface actuator at different flight speeds when the aileron is in a certain position.

[0036] refer to Figure 2 and Figure 3 The present invention provides a method for detecting and handling leaks in the piping of an aircraft control surface system, comprising the following steps:

[0037] Step 1. Obtain the no-load operating data of each control surface actuator from the factory data, including control surface position, actuator position, and hydraulic oil flow rate data; obtain the flight speed, actuator position, and hydraulic oil flow rate data of control surface deflection at different positions under various typical flight profiles from the flight data. After removing outliers, the above data will be used as modeling data.

[0038] Step 2. Obtain the hydraulic oil flow velocity in the aileron pressurization line based on the flow velocity sensor; based on the LVDT (Low Level Drone) signal, obtain the actuator position values ​​at different flight speeds and when the aileron control surfaces are deflected at different positions. Calculate the ratio of the difference in actuator position change to time at 100ms intervals to obtain the actuator speed; based on the known hydraulic oil flow velocity and actuator speed data in the pressurization line, perform a quadratic polynomial fitting using the least squares method to obtain the functional relationship, which serves as the flow velocity monitoring model, such as... Figure 3 .

[0039] The fitted functional relationship is f = ax 2 Formula for calculating the coefficient of +bx+c:

[0040]

[0041] In the formula above, x and y represent the raw data of the actuator's oil flow rate and motion speed, respectively, and the horizontal line above the letter represents the average value of the data.

[0042] Step 3. The flight control computer collects actuator velocity data and calculates the hydraulic oil flow rate in the pressure supply line using the flow rate model from Step 2. The calculated value is then compared with the actual sampled value from the flow rate sensor. A monitoring threshold of 2% is set for a duration of 300ms; if the difference exceeds 2% of the calculated value, the leakage fault determination condition is met.

[0043] Step 4. To improve the reliability of fault diagnosis, dual-level alarm signals from the relevant hydraulic tanks are introduced for final judgment and control output. If both of the following conditions are met simultaneously and last for 300ms, the flight control computer determines that there is a leak in the pressure supply line of the control surface actuator.

[0044] 1) |Calculated flow velocity - Actual sampled value| > 2% * Calculated flow velocity

[0045] 2) The relevant hydraulic oil tank dual-level alarm signal persists.

[0046] After a pipeline leak is detected, the flight control computer issues a control command to close the pressure supply shut-off valve, cutting off the fuel supply, and allowing the backup pressure supply line to drive the control surface actuators. When the pressure supply line leaks, the actuator speed will significantly decrease at the same fuel flow rate, such as... Figure 4 . Figure 4 This is a schematic diagram of a leak detection method for the pressure supply line of a rudder actuator according to an embodiment of the present invention.

[0047] It should be noted that, without conflict, those skilled in the art can flexibly adjust the order of the above operation steps or flexibly combine the above steps as needed. For the sake of brevity, various implementation methods will not be described in detail. In addition, the contents of the various embodiments can be referenced and cited interchangeably.

[0048] The present invention provides a method for detecting and handling leaks in the piping of an aircraft control surface system, which has the following advantages.

[0049] a. Novel Method. This invention utilizes the working principle of the rudder surface actuator and related parameter recording data to establish a pipeline flow velocity model, compares and detects the actual flow velocity in the pipeline, and introduces dual liquid level alarm signals from the relevant hydraulic oil tank for final judgment and control output. This method is novel and represents the first application in the field of fault diagnosis.

[0050] b. Simple to implement. The relevant parameter data involved in this invention are easy to obtain, and fitting is easy to achieve.

[0051] c. Simple field modification. The solution of this invention can be implemented on existing aircraft. The hardware only requires the addition of a flow rate sensor and a dual liquid level alarm, and the wiring only needs to be adapted. Field modification is easy.

[0052] d. This invention enables the detection of leaks in pressurized pipelines that endanger flight safety, thus effectively ensuring flight safety.

[0053] e. This invention provides a method for detecting leakage faults in the pressure supply lines of aircraft control surface actuators, which makes up for the lack of current methods for detecting leakage faults in control surface system lines.

[0054] f. Promising application prospects. This invention can also be applied to the detection of leaks in the control surface operating system pipelines of UAVs and transport aircraft.

[0055] Therefore, this invention provides a method for detecting and handling leaks in the piping of an aircraft control surface system, which fills the gap in current methods for detecting leaks in the control surface pressure supply piping and plays a positive role in ensuring aircraft flight safety.

[0056] In some embodiments, the present invention provides a device for detecting and handling leaks in the piping of an aircraft control surface system. The device includes: a data acquisition module, a data processing module, and a control output module. Specifically: the data acquisition module is used to acquire operating data of each control surface under no-load conditions from ground test data and to acquire operating data of each control surface from in-flight data; the data processing module is used to obtain the position values ​​of the control surface actuator cylinders at different flight speeds based on the position signals of the control surface actuator cylinders, calculate the actuator cylinder movement speed V1, and obtain a flow velocity monitoring model for the control surface actuator pressure supply piping based on V1; calculate the hydraulic oil flow velocity in the pressure supply piping using the flow velocity model, and compare the calculated flow velocity value with the actual sampled flow velocity value; set up fault judgment logic to determine whether there is a leak in the control surface actuator pressure supply piping based on the comparison result of the calculated flow velocity value and the actual sampled flow velocity value; the control output module is used to handle the fault after determining a piping leak fault.

[0057] The aforementioned device can serve as the executing entity for the aforementioned method, performing the aforementioned process steps, solving the aforementioned technical problems, and achieving the aforementioned technical effects. For the sake of brevity, the details of the aforementioned invention also apply to this device, and identical or similar content will not be repeated. The content of the aforementioned invention and the content of this device can be referenced and cited interchangeably.

[0058] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary hardware platforms, and of course, it can be implemented directly by hardware. Based on this understanding, the above technical solutions, in essence, or the part that contributes to the prior art, can be embodied in software form. This computer software can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc. The readable storage medium can store programs, instructions, etc., causing a computer device (such as a personal computer, server, or network device, etc.) to execute the methods described in the previous embodiments.

[0059] Those skilled in the art will recognize that the various program (functional) modules and execution steps described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, whether a unit or step of the above technical solution is executed in hardware or software may depend on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the various embodiments for each specific application.

[0060] The methods and apparatus disclosed in the above embodiments can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For example, the division of the various units described above is only a logical functional division, and there may be other division methods in practice. For example, multiple important units can be combined or integrated into a device or system, or they can exist physically separately. Other non-important features, units, devices, etc., can be ignored or not executed. The specific arrangement of each unit within the device can be customized according to actual needs.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should be covered within the protection scope of the present invention.

Claims

1. A method for detecting and handling leaks in the piping of an aircraft control surface system, characterized in that, Includes the following steps: S1: Obtain the working data of each control surface under no-load conditions from the aircraft ground test data; S2, obtains the working data of each control surface from the aircraft's in-flight data; S3. Based on the position signal of the control surface actuator, the position value of the control surface actuator at different positions of the control surface deflection at different flight speeds is obtained, the movement speed of the actuator V1 is calculated, and the flow velocity monitoring model of the control surface actuator pressure supply pipeline is obtained based on V1. S4 calculates the hydraulic oil flow rate in the pressure supply pipeline using the flow rate monitoring model in S3, and compares the calculated flow rate value with the actual sampled flow rate value. S5, set the fault judgment logic, and determine whether there is a leak in the pressure supply pipeline of the rudder actuator based on the comparison result between the calculated flow velocity value and the actual sampled flow velocity value. S6, After determining that there is a pipeline leak, proceed with the troubleshooting. In step S3: The hydraulic oil flow velocity in the aileron pressurization line is measured by a flow velocity sensor. Based on the position signal of the control surface actuator, the position values ​​of the control surface actuator cylinder are obtained when the control surface deflects at different positions at different flight speeds. The ratio of the difference in the position change of the control surface actuator cylinder to time is calculated at 100ms intervals to obtain the movement speed of the control surface actuator cylinder. Based on the known hydraulic oil flow velocity in the pressurization line and the movement speed of the control surface actuator, a quadratic polynomial fitting is performed using the least squares method to obtain the functional relationship, which serves as the flow velocity monitoring model.

2. The method for detecting and handling leaks in the piping of an aircraft control surface system according to claim 1, characterized in that, In steps S1 and S2: The operating data of each control surface obtained from the ground test data includes control surface position, control surface actuator position, and hydraulic oil flow rate data; the flight speed, actuator position, and hydraulic oil flow rate data of control surface deflection at different positions under various typical flight profiles are obtained from the flight data; after removing outliers, the above data are used as modeling data.

3. The method for detecting and handling leaks in the piping of an aircraft control surface system according to claim 1, characterized in that, In step S3: The functional relationship is: The formulas for obtaining the coefficients of this relation are as follows: ； Where x and y represent the raw data of the actuator's oil flow rate and motion speed, respectively, and the horizontal line above the letter represents the average value of the data.

4. The method for detecting and handling leaks in the piping of an aircraft control surface system according to claim 1, characterized in that, In step S4: The flight control computer collects the motion speed data of the control surface actuators, calculates the hydraulic oil flow rate in the pressure supply line through the flow rate model, and compares the calculated value with the actual sampled value of the flow rate sensor.

5. The method for detecting and handling leaks in the piping of an aircraft control surface system according to claim 1, characterized in that, In step S5: Set the monitoring threshold to 2% and the duration to 300ms. A difference exceeding 2% of the calculated value is considered a condition for determining leakage fault.

6. The method for detecting and handling leaks in the piping of an aircraft control surface system according to claim 1, characterized in that, In step S5: The dual-level alarm signals from the relevant hydraulic oil tank are used for final judgment and control output.

7. The method for detecting and handling leaks in the piping of an aircraft control surface system according to claim 6, characterized in that, In step S5: If both of the following conditions are met simultaneously and last for 300ms, the flight control computer determines that there is a leak in the pressure supply line of the control surface actuator: Condition 1 is: |Calculated flow rate - Actual sampled flow rate| > 2% * Calculated flow rate; Condition 2 is: the relevant hydraulic oil tank dual level alarm signal continues to exist.

8. A method for detecting and handling leaks in the piping of an aircraft control surface system according to any one of claims 1-7, characterized in that, In step S6: After determining that the pipeline is leaking, the flight control computer issues a control command to close the pressure supply pipe shut-off valve, cut off the fuel supply, and drive the control surface actuators to work through the backup pressure supply pipe.

9. A device for detecting and handling leaks in the piping of an aircraft control surface system, characterized in that, include: The module comprises a data acquisition module, a data processing module, and a control output module, among which: The data acquisition module is used to obtain the working data of each control surface under no-load conditions from the aircraft ground test data; and to obtain the working data of each control surface from the aircraft flight data. The data processing module is used to obtain the position values ​​of the control surface actuator cylinder at different flight speeds based on the control surface actuator cylinder position signal, calculate the actuator cylinder motion velocity V1, and obtain a flow velocity monitoring model for the control surface actuator pressure supply line based on V1. The flow velocity monitoring model is used to calculate the hydraulic oil flow velocity in the pressure supply line, and the calculated flow velocity value is compared with the actual sampled flow velocity value. Fault detection logic is set to determine whether there is a leak in the control surface actuator pressure supply line based on the comparison result of the calculated and actual sampled flow velocity values. The hydraulic oil flow rate in the aileron pressurization line is measured by a flow rate sensor. Based on the position signal of the control surface actuator, the position values ​​of the control surface actuator cylinders at different flight speeds and when the control surface deflects at different positions are obtained. The ratio of the difference in the position change of the control surface actuator cylinders to time is calculated at 100ms intervals to obtain the movement speed of the control surface actuator cylinders. Based on the known hydraulic oil flow rate in the pressurization line and the movement speed data of the control surface actuators, a quadratic polynomial fitting is performed using the least squares method to obtain the functional relationship, which serves as the flow rate monitoring model. The control output module is used to handle pipeline leaks and other faults.

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