Ground monitoring method and system for zero drift of an air route aircraft angle of attack sensor

Abstract

The application relates to a ground monitoring method and system for the angle of attack sensor zero drift problem of a line airplane, which comprises the following steps: collecting various flight parameters in the flight process of the line airplane; judging whether the airplane is in a cruising steady flight stage according to the collected flight parameters; when it is determined that the airplane is in the cruising steady flight stage, calculating the actual angle of attack of the airplane according to the related flight parameters by using a kinematic relationship; and judging whether to issue an angle of attack sensor zero drift warning according to whether the deviation between the actual angle of attack and the tabled angle of attack of the airplane is greater than a deviation threshold. Wherein, judging the cruising steady flight stage is screening for a steady flight section.

Description

Technical Field

[0001] This application relates to the field of flight control in civil aviation, and in particular to a ground monitoring method and system for monitoring whether the angle of attack sensor of a line aircraft is experiencing zero-point drift. Background Technology

[0002] During civil aircraft route operations, angle-of-attack (AOA) data is a core input for flight control computers, stall warning systems, and air data systems. Aircraft need to monitor the zero-point drift of each AOA anemometer sensor. The core function of this monitoring is to ensure the absolute accuracy of the AOA data, which forms the basis for decisions in critical systems such as flight control and stall warning, thereby fundamentally preventing the risk of aircraft loss of control due to signal errors.

[0003] If an angle-of-attack wind vane zero-point drift fault occurs during flight and the aircraft cannot detect the fault, it will become a hidden fault, which will further reduce the integrity and safety of the aircraft's system. Therefore, current civil aircraft flight operations urgently need a set of angle-of-attack wind vane sensor zero-point drift fault monitoring technology.

[0004] Many existing technologies have proposed solutions for monitoring whether the angle-of-attack sensors of aircraft on flight paths are experiencing zero-position drift.

[0005] For example, patent document CN117308996A discloses a specific monitoring method and system for angle-of-attack sensor blade jamming to solve the angle-of-attack sensor jamming fault in aircraft. This method first acquires angle-of-attack detection data from historical flights, and obtains the angle-of-attack threshold range based on the historical flight's angle-of-attack detection data during the cruise phase. Then, it acquires angle-of-attack detection data from the three sensors of the aircraft under test during the takeoff phase, calculates the differences between each pair, and performs probability density function fitting on the three difference groups to obtain the corresponding offsets. Finally, it calculates the differences between these three offsets and the corresponding offsets of a normal aircraft's angle-of-attack sensor, and determines the health status of the angle-of-attack sensor based on the differences.

[0006] This patent document determines the health of angle-of-attack sensors by comparing the offset calculated from the differences between the three angle-of-attack sensors of the aircraft under test with the corresponding offset of a normal aircraft's angle-of-attack sensor. However, the solution itself is based on the sensing data from different angle-of-attack sensors. Due to the homogeneity of angle-of-attack sensors, when external conditions (such as severe weather) adversely affect one sensor, the remaining sensors may also be affected. In such a scenario, the solution will malfunction, posing a potential safety hazard.

[0007] For example, patent CN106767911A discloses a method for signal acquisition and fault monitoring of an aircraft angle-of-attack sensor. This method improves the acquisition accuracy of the angle-of-attack sensor by using ±15V as a reference voltage and a voltage amplification circuit, solving the problem of large acquisition gradient and low accuracy in angle-of-attack sensors. It also achieves fault monitoring of the angle-of-attack sensor by manually setting an electrical zero-point bias. This patent document's solution uses a power module to output low-end -15V and high-end 15V voltages as reference voltages for a weather vane sliding rheostat, addressing the problem of large acquisition gradient and low accuracy in weather vane-type angle-of-attack sensors based on the sliding rheostat principle. Furthermore, it identifies typical open-circuit faults by manually setting an electrical zero-point bias, improving signal fault monitoring coverage. However, this solution clearly requires adding detection equipment to the angle-of-attack sensor, increasing cost and failure rate.

[0008] Therefore, existing technologies all rely on the signals and data output by the angle-of-attack sensor itself to determine whether a fault has occurred, primarily monitoring and detecting the sensor itself. Furthermore, all of these technologies require the addition of detection equipment to the angle-of-attack sensor or can only be inspected after the aircraft has landed. This results in delayed monitoring, cumbersome detection processes, and high costs in terms of time, labor, and equipment. Moreover, existing technologies are limited in their application scope; if detection equipment cannot be added to the aircraft's angle-of-attack sensor or if angle-of-attack sensor data cannot be obtained, existing technologies struggle to monitor and detect angle-of-attack sensor faults. Summary of the Invention

[0009] The purpose of this application is to provide a ground monitoring technology for the zero-point drift problem of the aircraft's angle of attack sensor. The technology calculates the actual angle of attack during the stable cruise phase of the aircraft's flight path based on key flight parameters, compares it with the voting angle of attack signal, and then determines whether the aircraft's angle of attack sensor has experienced a zero-point drift problem.

[0010] According to a first aspect of this application, a ground monitoring method for the zero-point drift problem of angle-of-attack sensors on airliners is provided, comprising: Collect various flight parameters during the flight of an aircraft on a flight path; Determine whether the aircraft is in a stable cruise flight phase based on the collected flight parameters; When it is determined that the aircraft is in the cruise stable flight phase, the actual angle of attack of the aircraft is calculated using relevant flight parameters based on kinematic relationships; Whether to issue an angle-of-attack sensor zero-drift alarm is determined by whether the deviation between the actual angle of attack and the aircraft's actual angle of attack is greater than a deviation threshold.

[0011] The determination of the cruise stable flight phase is a screening of the steady flight phase.

[0012] According to a second aspect of this application, a ground monitoring system for addressing the zero-point drift problem of angle-of-attack sensors in airliners is provided, comprising: The flight parameter acquisition module is configured to collect various flight parameters during the flight of an aircraft on a flight path; The stable flight phase determination module is configured to determine whether the aircraft is in the cruise stable flight phase based on some collected flight parameters. The aircraft actual angle of attack calculation module is configured to calculate the aircraft's actual angle of attack based on kinematic relationships and relevant flight parameters when it is determined that the aircraft is in the cruise stable flight phase. Angle of attack sensor zero drift alarm module is configured to determine whether to issue angle of attack sensor zero drift alarm based on whether the deviation between the actual angle of attack and the aircraft's default angle of attack is greater than a deviation threshold; The determination of the cruise stable flight phase is a screening of the steady flight phase.

[0013] This overview is provided to introduce, in a simplified form, some of the concepts further described in the detailed description below. This overview is not intended to identify key or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter. Attached Figure Description

[0014] To describe how the above and other advantages and features of the invention are obtained, a more detailed description of the invention, which has been briefly described above, will be presented with reference to specific embodiments of the invention shown in the accompanying drawings. It will be understood that these drawings depict only exemplary embodiments of the invention and are therefore not intended to limit its scope. The invention will be described and explained using the drawings and with the aid of additional features and details, in which: Figure 1 A schematic flowchart of a ground monitoring method for zero-point drift of an angle-of-attack sensor for a flight path aircraft, according to an embodiment of this application, is shown.

[0015] Figure 2 A schematic structural diagram of a ground monitoring system for addressing the zero-point drift problem of an angle-of-attack sensor for airliners, according to one embodiment of this application, is shown. Detailed Implementation

[0016] The technical solution of this application is a ground monitoring technology for the zero-point drift problem of the angle of attack sensor of an aircraft.

[0017] The main difference between this invention and existing technologies is that existing technologies rely on the data output by the angle-of-attack sensor itself to determine whether a fault has occurred. This primarily involves monitoring and detecting the sensor itself, requiring additional detection equipment on the sensor or waiting until the aircraft lands before testing. In contrast, this invention calculates the actual angle of attack using the acquired aircraft aerodynamic parameters and compares it with the aircraft's actual angle of attack to determine if the angle-of-attack sensor has experienced zero-point drift. This overcomes the limitations of existing technologies that require analysis of the sensor's output data to determine fault status. Furthermore, it allows monitoring during flight without waiting for landing, expanding the fault monitoring coverage, opening up new fault monitoring paths, and eliminating the need for additional detection equipment on the sensor, thus saving time, labor, and equipment costs associated with fault monitoring.

[0018] Specifically, in Figure 1 The image shows a ground monitoring method for zero-point drift of the angle-of-attack sensor of a flight line aircraft, according to one embodiment of this application.

[0019] like Figure 1 As shown, firstly, in step 102, various flight parameters are collected during the flight of the airliner. For example, during the flight of the airliner, key parameters such as pitch angle, climb angle, vertical speed, vacuum speed, roll angle, normal overload, lateral overload, angle of attack, corrected airspeed, pitch rate, roll rate, and sideslip angle can be read from various sensors equipped on the aircraft.

[0020] These parameters can be divided into two categories based on their function: 1) Parameters used to determine the cruise stable flight phase, such as: normal overload, lateral overload, vertical speed, rate of change of angle of attack, rate of change of corrected airspeed, pitch rate, roll rate and sideslip angle, etc. These parameters are used to determine whether the aircraft is in the cruise stable flight phase. 2) Parameters used to calculate the angle of attack deviation during the stable cruise phase of the aircraft, such as pitch angle, climb angle, vertical speed, vacuum speed, and roll angle. These parameters are used to calculate the actual angle of attack during the stable cruise phase of the aircraft.

[0021] It should be understood that the examples of collected flight parameters given above are for illustrative purposes and are not intended to limit the scope of the examples.

[0022] Subsequently, in step 104, it is determined whether the aircraft is in the stable cruise flight phase based on the collected partial flight parameters.

[0023] Determining whether a civil aircraft is in a stable cruise flight phase is crucial for the subsequent calculation of the "actual angle of attack" (or "true angle of attack" or "aerodynamic angle of attack").

[0024] This is mainly because the angle of attack is essentially an aerodynamic equilibrium state parameter, rather than a simple geometric angle that can be directly measured. If the actual angle of attack is calculated during unstable phases (such as climbing, descending, turning, acceleration / deceleration, or encountering turbulence), the result will be affected by interference factors such as inertial forces, angular acceleration, and dynamic delays, making it impossible to accurately separate the zero-point drift of the sensor.

[0025] On the other hand, determining the stable flight phase of cruise is essentially a selection of steady flight segments. Because calculating the actual angle of attack of an aircraft under unsteady conditions involves multiple parameters, the calculation is difficult and inaccurate. Therefore, to simplify the calculation process, reduce the difficulty, and improve the accuracy, the flight path data needs to be preprocessed to select all steady flight segments during a flight before calculating the actual angle of attack. Here, "steady" refers to the aircraft's motion parameters not changing over time. In flight mechanics, if an aircraft's core state variables, such as linear velocity and angular velocity, remain constant (or their changes are within a very small allowable range) for a certain period, then this period can be called a "steady flight segment."

[0026] The steady flight phase can usually be determined by parameters such as overload, speed, attitude angle and angular acceleration, and sideslip angle in the flight parameters.

[0027] Specifically, since "stability" during the cruise phase means that the aircraft is in a controlled equilibrium state, without maneuvers, and with smooth airflow, the rate of change or the values ​​of most parameters should be close to zero (or a specific baseline value). Based on this, a set of commonly used criteria for judging steady flight conditions is as follows: Normal overload change |ΔNzb| ≤ 0.02 g; Lateral overload |Nyb|≤0.02 g; Vertical velocity |Vz| ≤ 200 ft / min; Rate of change of angle of attack | |≤0.2 deg / s; Rate of change of velocity | |≤0.5 Kts / s; Pitch rate |q| ≤ 0.2 deg / s; Roll rate |p|≤0.2 deg / s; Sideslip angle | |≤0.5 deg; Roll angle | |≤1 deg.

[0028] Once all of the above conditions are met, the aircraft can be determined to be in a steady flight phase. The aforementioned flight parameters should all undergo preliminary cleaning and filtering beforehand.

[0029] However, since atmospheric conditions vary and are not ideally stable during actual flight routes, strictly adhering to the above criteria for judging stable flight conditions when selecting stable flight segments may result in too few stable flight segments being selected, thus affecting the accuracy of monitoring.

[0030] Therefore, this application further introduces a stability scoring method to improve the screening efficiency of steady flight segments.

[0031] The calculation of the stability score mainly involves the following steps: a. Calculate the stability score for each individual flight parameter using standard numerical comparison scores and single-parameter stability scores.

[0032] The basic algorithm used for the standard numerical comparison scoring is to compare parameters. and standard values The absolute deviations are respectively compared with two reference thresholds. and Comparison: when At that time, the score is fixed at 1. when At that time, the score changes linearly from 1 to 0. when At that time, the score is fixed at 0. Right now: .

[0033] This formula defines a piecewise linear scoring function for quantifying parameters. and standard values The degree of deviation is determined and the degree of deviation is mapped to a score value in the interval [0,1].

[0034] The single-parameter stationarity score uses a range formula within a sliding window: Let... For parameters In recent The difference between the maximum and minimum values ​​within a range of numbers, i.e.: .

[0035] The window range is defined as follows: taking the nth data point as the center, and selecting k points forward and k points backward (a total of 2k+1 points). Range: The difference between the maximum and minimum values ​​of parameter x within this window, that is, the fluctuation range of parameter x within this time interval.

[0036] This range reflects the short-term stability of parameter x within a local time range: The smaller the range, the smaller the parameter fluctuation, and the better the stability during that time period.

[0037] The larger the range, the greater the parameter fluctuation, indicating significant dynamic changes that do not meet the steady-state requirement.

[0038] In this way, using standard numerical comparison scoring and single-parameter stationarity scoring can achieve the following advantages: 1) Change hard threshold judgment to soft scoring to avoid losing usable data segments due to small fluctuations.

[0039] 2) Unify the evaluation methods for parameters with different dimensions (altitude, airspeed, overload, angle, etc. can all be processed using the same 0~1 rating framework).

[0040] 3) Provides continuous and comparable input for subsequent geometric mean comprehensive scoring and morphological interval extraction, and finally selects flight segments that are both stable and long enough to ensure the accuracy of actual angle of attack calculation and data availability.

[0041] Without the aforementioned stability scoring formula, one would have to rely on the strict conditions specified in commonly used steady flight conditions, which would likely result in insufficient steady flight segments being selected from actual flight data, thus affecting the monitoring effect.

[0042] The following examples illustrate in detail the calculation process of the stability score for each flight parameter.

[0043] For example, in terms of altitude, airspeed, and acceleration When using four parameters—including angle—as the primary basis for stability scoring, the specific calculation process for the stability score includes: 1) Height: .

[0044] in, A score indicating the stability of (barometric) altitude; Indicates the current air pressure altitude; Indicates the maximum pressure altitude during flight; parameter A lower limit for the altitude "approaching cruise" is defined to ensure that the level flight phase at the end of climb / the beginning of descent is included. Based on engineering experience, this value can be taken as [value missing]. ; An upper limit for altitude "exceeding cruise" is defined: exceeding the maximum altitude for this flight is considered an anomaly, and its value is 1; The width of the sliding window is defined (this width takes into account both noise filtering and response speed), which is based on the time constant of the flight control system, and can be set to 20s here; A threshold for "perfectly acceptable" altitude fluctuation is defined, which references the accuracy of the automatic flight system plus statistical quantiles, and can be 6ft. A threshold for "completely unacceptable" altitude fluctuations is defined, which is based on the accuracy of the automatic flight system plus the statistical quantile, and can be set to 12ft.

[0045] 2) Airspeed: .

[0046] in, The rating indicates the smoothness of airspeed. Indicates the current airspeed; Indicates the maximum indicated airspeed during flight; parameter and The full and zero zones are defined for comparing the current airspeed with the maximum cruising airspeed. Based on engineering experience, these zones can be set to values ​​of [values ​​to be filled in]. and 1; The half-width of the sliding window used to calculate short-term fluctuations is defined, with a value of 20s; and The full and zero zones of the airspeed fluctuation range are defined respectively, with values ​​of 3kn and 6kn. 3) Acceleration : .

[0047] in, The smoothness score representing acceleration; parameters A threshold for "perfectly qualified" normal overload deviation was defined, which referenced the typical accuracy of the automatic flight system plus the statistical quantile, and was set to 0.02g. A threshold for "completely unacceptable" normal overload deviation was defined, which referenced the statistical quantile that distinguishes between minor disturbances and significant maneuvers, and its value was 0.04g. 4) Angle: .

[0048] in, The rating indicates the smoothness of the angle. A smoothness score for the roll angle was defined; s γ A stability score for the heading angle (yaw angle) is defined; s θ A stability score for the pitch angle is defined, where: ; ; ; in,d ( , t 2) This represents the difference between the maximum and minimum values ​​of the roll angle within a t2-second window (i.e., the fluctuation range). d ( , t 2) This represents the difference between the maximum and minimum heading angles within a t2-second window; d ( θ , t 2) Represents the difference between the maximum and minimum pitch angles within a t2-second window. Parameter The half-width of the sliding window used to calculate short-term fluctuations is defined, with a value of 20s; , The "perfectly qualified" threshold and "completely unqualified" threshold for the roll angle fluctuation are defined, with values ​​of 1° and 2° respectively. , The "perfectly acceptable" and "completely unacceptable" thresholds for the fluctuation of the heading angle are defined, with values ​​of 1° and 2° respectively. , The pitch angle fluctuation thresholds for "perfectly qualified" and "completely unqualified" are defined, with values ​​of 1° and 2° respectively.

[0049] b. Calculate the overall stability score based on the stability scores of the individual flight parameters.

[0050] The selection of steady flight segments in this application is based on a stability overall score. The stability overall score S is the geometric mean of multiple stability scores, i.e., taking the above example parameters as an example: .

[0051] The above formula integrates the stability scores of four dimensions—altitude, airspeed, G-force, and attitude—using geometric mean to form a unified, quantifiable index S. This index is used to determine whether each data point belongs to a candidate state that is "sufficiently stable." Combined with subsequent morphological interval calculations, a high-quality, continuous, and sufficiently long steady flight segment is finally extracted from the original flight data, providing a reliable data foundation for actual angle-of-attack calculations.

[0052] c. Determine the stability threshold interval based on the overall stability score of each point along the flight path.

[0053] After calculating the overall stability score using the methods described in points a and b above, the stability of a single point along the flight path can be obtained. If intervals are directly divided according to a threshold, the interval segments may be quite fragmented. Therefore, this application further employs morphological operations on each interval to obtain simpler stable interval segments.

[0054] Its principle is to A subset The two basic morphological operations are: (1) (2) Equation (1) is the expansion operation σ k ( A ), meaning: to A Expand to the left and right of each point in the middle. k Take the union of the given points. Result: Fill in the gaps. A A gap of ≤ k (connecting two originally separate point sets) expands the range of the point set, extending the boundary outwards. k One point.

[0055] Equation (2) is the corrosion operation τ k( A Meaning: Only keep points in A whose distance from the complement of A (i.e., points not in A) is greater than k. Effect: Remove isolated segments of A with length ≤ k (because the points on the edges of these segments are ≤ k from the complement, and are therefore discarded), shrinking the boundary of the point set, causing each retained contiguous block to indent by k points.

[0056] Based on the above equations (1) and (2), let's denote... Their meanings are as follows: Remove items with a length not exceeding Isolated points; and intervals not exceeding The set of points is connected.

[0057] remember Flight data stability score greater than the threshold The subscript set. For Perform the following calculations: (3) For example, when Take 0.6, parameter , When the values ​​are 5 and 10 respectively, : Indices of all data points with a stationarity score S≥0.6 (a set of integers).

[0058] k 1: Open operation parameters, when k If 1=5, then isolated, short-lived high-scoring segments with a length of ≤ 5 points will be removed (which may be noise or random fluctuations).

[0059] k 2: Closed operation parameter, when k2=10, connect adjacent segments with an interval of ≤ 10 points to fill in the small gaps caused by temporary low scores.

[0060] After these two steps I It becomes the union of several disjoint consecutive integer intervals (i.e., I It consists of several non-overlapping intervals.

[0061] d. Extract the corresponding interval endpoints based on the defined stable threshold intervals.

[0062] because I Since it is already the union of consecutive integer intervals, the next step is simply to find the left endpoint of each consecutive block. p n and right endpoint q n , so that:

[0063] The “ here” " indicates no union, [ p n , q n ] indicates from the endpoint p n To the endpoint q n All integers.

[0064] Finally, several consecutive stationary intervals are obtained. p n , q n Each interval corresponds to a continuous and sufficiently stable time period in the flight data.

[0065] It should be understood that, in addition to judgments based on the aforementioned flight parameters, other parameter combinations or logical expressions exist that can be used to determine whether an aircraft is in a stable cruise phase (i.e., filtering out steady flight segments). These logics typically focus on different data sources (such as inertial navigation, air data computers, and flight management systems) or system status indicators, but the core idea remains the same: verifying that the aircraft is in a balanced, non-accelerating, and non-rotating state. For example, ground speed change rate (from GPS / IRS), engine parameter change rate, and automatic flight system status can also be used to construct stable cruise judgment logic, which will not be elaborated upon here. These different parameter combinations can verify each other, or the most suitable set can be selected according to the specific analysis purpose (such as performance monitoring and sensor calibration). In actual flight data analysis, multiple judgment logics can be combined, and the robustness of the judgment can be improved by using AND gates or weighted voting.

[0066] Furthermore, the various upper and lower limits and thresholds mentioned above are provided for illustrative purposes only and are not intended to be limiting. Technical personnel can make adaptive adjustments based on engineering experience and the actual machine model.

[0067] Subsequently, in step 106, when it is determined that the aircraft is in the stable cruise flight phase, the actual angle of attack of the aircraft is calculated using relevant flight parameters based on kinematic relationships.

[0068] An example of the kinematic relationship for calculating the actual angle of attack is to calculate the actual angle of attack of the aircraft during the cruise stable flight phase based on the pitch angle, climb angle, vertical velocity, free speed, and roll angle, as shown in the following formula: ; in, ; in: This is the calculated actual angle of attack; The pitch angle; The track angle is calculated using the formula; For roll angle; Vertical velocity; It is the vacuum velocity.

[0069] It should be understood that, in addition to the formulas mentioned above for calculating the actual angle of attack based on the kinematic relationships of pitch, climb, and roll angles, other methods exist in the civil aviation field for calculating the actual angle of attack. These methods each have their own focus and are suitable for different scenarios and needs.

[0070] Finally, in step 108, a zero-point drift alarm for the angle of attack sensor is issued based on whether the deviation between the calculated actual angle of attack and the aircraft's voted angle of attack during the stable cruise flight phase is greater than a deviation threshold.

[0071] The aircraft voting angle of attack refers to a single, reliable, and fault-tolerant representative angle of attack obtained by integrating the measurement values ​​of multiple independent angle of attack sensors on board through, for example, redundancy management logic. It can be considered the angle of attack measured by the angle of attack sensors and is the angle of attack most frequently referenced by the flight crew. In this application, the aircraft voting angle of attack can be obtained by voting on the angle of attack data collected from multiple angle of attack sensors in step 102.

[0072] The deviation threshold is an engineering experience value determined through statistical analysis of a large amount of historical flight data. It is used to determine whether the deviation between the "calculated actual angle of attack" and the "voted angle of attack" has exceeded the normal range, thereby triggering an alarm. In one example of this application, the deviation threshold can be set to 0.36°.

[0073] Therefore, the absolute value of the difference between the calculated actual angle of attack and the aircraft's voted angle of attack (the absolute value of the angle of attack deviation) can be compared with the deviation threshold: If the absolute value of the angle of attack deviation is greater than the deviation threshold, the system will issue an angle of attack sensor zero-point drift alarm, reminding ground staff to conduct a post-flight inspection of the angle of attack sensor to ensure the safety of flight operations.

[0074] If the absolute value of the angle of attack deviation is not greater than the deviation threshold, the angle of attack sensor is considered to be working normally, and the system will not issue an alarm.

[0075] Having understood the ground monitoring method for the zero-point drift problem of the angle-of-attack sensor of an aircraft in this application, the following will be combined with... Figure 2 To further illustrate a ground monitoring system for the zero-point drift problem of the angle of attack sensor of an aircraft according to this application.

[0076] As shown in the figure, the ground monitoring system includes a flight parameter acquisition module 202, a stable flight phase judgment module 204, an aircraft actual angle of attack calculation module 206, and an angle of attack sensor zero drift alarm module 208.

[0077] The flight parameter acquisition module 202 is configured to collect various flight parameters during the flight of a commercial airliner. For example, during the flight of a commercial airliner, key parameters such as pitch angle, climb angle, vertical speed, vacuum speed, roll angle, normal overload, lateral overload, angle of attack, corrected airspeed, pitch rate, roll rate, and sideslip angle can be read from various sensors equipped on the aircraft.

[0078] The stable flight phase determination module 204 is configured to determine whether the aircraft is in the cruise stable flight phase based on some of the collected flight parameters.

[0079] As mentioned above, this application further introduces a stability scoring mechanism to improve the screening efficiency of steady flight segments. The calculation of the stability score mainly involves the following steps: a. Calculate the stability score for each individual flight parameter using standard numerical comparison scores and single-parameter stability scores; b. Calculate the overall stability score based on the stability scores of these individual flight parameters; c. Divide the stability threshold interval based on the overall stability score of each point along the flight path; d. Extract the corresponding interval endpoints based on the defined stable threshold intervals.

[0080] The aircraft actual angle of attack calculation module 206 is configured to calculate the aircraft's actual angle of attack based on kinematic relationships and relevant flight parameters when the aircraft is determined to be in a stable cruise flight phase. For example, the actual angle of attack during the stable cruise flight phase can be calculated based on pitch angle, climb angle, vertical velocity, supersonic speed, and roll angle.

[0081] The angle-of-attack sensor zero-drift alarm module 208 is configured to determine whether to issue an angle-of-attack sensor zero-drift alarm based on whether the deviation between the calculated actual angle of attack and the aircraft's voted angle of attack during the stable cruise flight phase is greater than a deviation threshold.

[0082] If the absolute value of the angle of attack deviation is greater than the deviation threshold, the system will issue an angle of attack sensor zero-point drift alarm, reminding ground staff to conduct a post-flight inspection of the angle of attack sensor to ensure the safety of flight operations.

[0083] If the absolute value of the angle of attack deviation is not greater than the deviation threshold, the angle of attack sensor is considered to be working normally, and the system will not issue an alarm.

[0084] In summary, this application has the following advantages: 1. Calculate the aircraft's real-time angle of attack using the aircraft's aerodynamic parameters, and determine whether the angle of attack sensor has experienced zero-point drift by combining the aircraft's actual angle of attack.

[0085] 2. During the cruise phase, the actual angle of attack is calculated from the acquired aircraft aerodynamic parameters and compared with the aircraft's actual angle of attack from the angle of attack sensor to determine whether the angle of attack sensor has experienced a zero-point drift fault.

[0086] 3. Based on specific logic calculations, judgments, and selection of the stable flight segment of the aircraft's cruise, calculate the actual angle of attack of the stable flight segment of the aircraft's cruise according to the corresponding formula, and combine the calculated actual angle of attack with the voting angle of attack to determine whether the zero-position drift of the angle of attack sensor has occurred.

[0087] Although the techniques have been described using language specific to structural features and / or methodological actions, it should be understood that the appended claims are not necessarily limited to the described features or actions. Rather, these features and actions are described as exemplary forms of implementing these techniques.

[0088] The operations of the example processes are shown in separate boxes and are summarized with reference to these boxes. These processes are shown as a flow of logical boxes, each of which may represent one or more operations that can be implemented using hardware, software, or a combination thereof. In the context of software, these operations represent computer-executable instructions stored on one or more computer-readable media that, when executed by one or more processors, cause one or more processors to perform a given operation. Generally, computer-executable instructions include routines, programs, objects, modules, components, data structures, etc., that perform a particular function or implement a particular abstract data type. The order in which the operations are described is not intended to be construed as limiting, and any number of the operations may be executed in any order, combined in any order, subdivided into multiple sub-operations, and / or executed in parallel to implement the described process. The described process may be executed by resources associated with one or more computing devices, such as one or more internal or external CPUs or GPUs, and / or one or more pieces of hardware logic, such as FPGAs, DSPs, or other types of accelerators.

[0089] All of the methods and processes described above can be embodied in software code modules executed by one or more general-purpose computers or processors, and can be fully automated via these software code modules. These code modules can be stored on any type of computer-executable storage medium or other computer storage device. This code can also be packaged into corresponding computer program products. Some or all of these methods can alternatively be embodied in dedicated computer hardware.

[0090] Any routine description, element, or box in the flowcharts described herein and / or in the accompanying drawings should be understood as potentially representing a module, segment, or portion of code comprising one or more executable instructions for implementing a specific logical function or element in that routine. Alternative implementations are included within the scope of the examples described herein, wherein elements or functions may be removed or performed inconsistently with the order shown or discussed, including substantially synchronous or reverse order execution, depending on the functionality involved, as will be understood by those skilled in the art.

[0091] While different embodiments have been described above, it should be understood that they are merely examples and not limitations. Those skilled in the art will appreciate that various modifications in form and detail may be made without departing from the spirit and scope of the invention as defined in the appended claims. Therefore, the breadth and scope of the invention disclosed herein should not be limited by the exemplary embodiments disclosed above, but should be defined solely by the appended claims and their equivalents.

Claims

1. A ground monitoring method for addressing the zero-point drift problem of angle-of-attack sensors on airliners, comprising: Collect various flight parameters during the flight of an aircraft on a flight path; Determine whether the aircraft is in a stable cruise flight phase based on the collected flight parameters; When it is determined that the aircraft is in the cruise stable flight phase, the actual angle of attack of the aircraft is calculated using relevant flight parameters based on kinematic relationships; Whether to issue an angle-of-attack sensor zero-drift alarm is determined by whether the deviation between the actual angle of attack and the aircraft's actual angle of attack is greater than a deviation threshold. Among them, the determination of the cruise stable flight phase is to use the stability scoring method to screen out the steady flight segment; The stability scoring method includes: a. Calculate the stability score for each individual flight parameter using standard numerical comparison scores and single-parameter stability scores; b. Calculate the overall stability score based on the stability scores of each individual flight parameter; c. Divide the stability threshold interval based on the total stability score at each point along the flight path; d. Extract the corresponding interval endpoints based on the defined stable threshold intervals.

2. The ground monitoring method as described in claim 1, characterized in that, The collected flight parameters are divided into the following two categories: 1) Flight parameters used to determine the cruise stable flight phase, including: normal overload, lateral overload, vertical speed, rate of change of angle of attack, rate of change of corrected airspeed, pitch rate, roll rate and sideslip angle; 2) Flight parameters used to calculate angle of attack deviation during the stable cruise phase of an aircraft, including: pitch angle, climb angle, vertical speed, vacuum speed, and roll angle.

3. The ground monitoring method as described in claim 2, characterized in that, The flight parameters used to determine the cruise stable flight phase are selected based on the following steady flight conditions: Normal overload change |ΔNzb| ≤ 0.02 g; Lateral overload |Nyb|≤0.02 g; Vertical velocity |Vz| ≤ 200 ft / min; Rate of change of angle of attack | |≤0.2 deg / s; Rate of change of velocity | |≤0.5 Kts / s; Pitch rate |q| ≤ 0.2 deg / s; Roll rate |p|≤0.2 deg / s; Sideslip angle | |≤0.5 deg; Roll angle | |≤1 deg.

4. The ground monitoring method as described in claim 1, characterized in that, The standard numerical comparison score includes: ； Among them, the parameters and standard values The absolute deviations are respectively compared with two reference thresholds. and Comparison: when At that time, the score is fixed at 1. when At that time, the score changes linearly from 1 to 0. when At that time, the score is fixed at 0; The single-parameter stationarity score includes the range formula within the following sliding window: ； The window range is defined as follows: taking the nth data point as the center, k points are taken forward and k points are taken backward, for a total of 2k+1 points; For parameters In recent The difference between the maximum and minimum values ​​within a range of numbers.

5. The ground monitoring method as described in claim 4, characterized in that, The calculation of the overall stability score based on the stability score of the individual flight parameters includes calculating the overall stability score S according to the following formula: in, A score indicating a high degree of stability. The score representing the stability of airspeed. The smoothness score representing acceleration. The rating indicates the smoothness of the angle.

6. The ground monitoring method as described in claim 5, characterized in that, The stability threshold interval segment, which is based on the overall stability score at each point along the flight path, includes: The following morphological operations are applied to each interval to obtain the corresponding stationary interval segments: right A subset : （1） （2） （3） Equation (1) is the expansion operation. Meaning: Expand each point in A by k points to the left and right, and take the union of the results; Equation (2) is the corrosion operation Meaning: Only keep those points in A whose distance from the complement of A is greater than k; Based on equations (1) and (2), let's denote... Their meanings are as follows: Remove items with a length not exceeding Isolated points and intervals not exceeding The set of points is connected; The set of subscripts for flight data stability scores greater than a threshold; k 1: Opening operation parameters; k 2: Closing operation parameters; I It is the union of several disjoint consecutive integer intervals.

7. The ground monitoring method as described in claim 6, characterized in that, The step of extracting the corresponding interval endpoints based on the divided stable threshold intervals includes determining the interval endpoints according to the following formula: ; in, Indicates no-intersection union, [ p n , q n ] indicates from the endpoint p n To the endpoint q n All integers.

8. The ground monitoring method as described in claim 1, characterized in that, When it is determined that the aircraft is in the cruise stable flight phase, calculating the actual angle of attack of the aircraft based on kinematic relationships and relevant flight parameters includes: The actual angle of attack during the stable cruise flight phase of the aircraft is calculated based on the pitch angle, climb angle, vertical velocity, supersonic speed, and roll angle. ； in, ; in: This is the calculated actual angle of attack; The pitch angle; The track angle is calculated using the formula; This refers to the roll angle; Vertical velocity; It is the vacuum velocity.

9. A ground monitoring system for addressing the zero-point drift problem of angle-of-attack sensors in airliners, comprising: The flight parameter acquisition module is configured to collect various flight parameters during the flight of an aircraft on a flight path; The stable flight phase determination module is configured to determine whether the aircraft is in the cruise stable flight phase based on some collected flight parameters. The aircraft actual angle of attack calculation module is configured to calculate the aircraft's actual angle of attack based on kinematic relationships and relevant flight parameters when it is determined that the aircraft is in the cruise stable flight phase. Angle of attack sensor zero drift alarm module is configured to determine whether to issue angle of attack sensor zero drift alarm based on whether the deviation between the actual angle of attack and the aircraft's default angle of attack is greater than a deviation threshold; Among them, the determination of the cruise stable flight phase is to use the stability scoring method to screen out the steady flight segment; The stability scoring method includes: a. Calculate the stability score for each individual flight parameter using standard numerical comparison scores and single-parameter stability scores; b. Calculate the overall stability score based on the stability scores of each individual flight parameter; c. Divide the stability threshold interval based on the total stability score at each point along the flight path; d. Extract the corresponding interval endpoints based on the defined stable threshold intervals.

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