A data processing method and system for low altitude aerial vehicle detection

Abstract

The application discloses a kind of low-altitude aircraft detection data processing method and system.The method is executed by data processing equipment, comprising: the operating state parameter sequence of low-altitude aircraft is collected;The operating state parameter sequence is preprocessed and feature is solved, and electromechanical response characteristic signal is obtained;The system delay constant between the electromechanical response characteristic signal is extracted;The electromechanical response characteristic signal is compared with consistency, and synchronization deviation degree index is obtained;According to the space height parameter and the synchronization deviation degree index, aircraft structure health state is judged, and detection conclusion is output.Through the physical delay of adaptive calibration system inherent, and the relative change rate of electric energy input and mechanical response is introduced to carry out time domain alignment comparison, effectively peel off common-mode interference such as external environmental wind disturbance, realize in not depending on internal flight control system log black box state, to aircraft microstructure fatigue and mechanical transmission loosening defect Precision detection.

Description

Technical Field

[0001] This invention relates to the field of low-altitude aircraft inspection and safety assessment technology, and in particular to a data processing method and system for non-destructive testing of the exterior of low-altitude aircraft based on the physical evolution of electromechanical parameters. Background Technology

[0002] With the development of the low-altitude economy, third-party testing laboratories need to conduct airworthiness, stability, and structural health tests on various low-altitude aircraft. As third-party organizations, they typically cannot obtain the encrypted low-level flight control system logs or closed-loop control parameters from aircraft manufacturers.

[0003] Existing technologies, without relying on internal source code, typically employ methods that independently analyze fuselage vibration amplitude or abnormal motor current peaks. However, this conventional testing approach has a blind spot that is easily overlooked: in complex low-altitude testing environments such as urban wind shear and micro-turbulence simulation tests, the "normal high-frequency vibrations and current jumps generated by the flight control system's active wind disturbance resistance" and the "abnormal vibrations and current fluctuations generated by aircraft structural defects (such as slight loosening of the fuselage arms and early wear of the transmission chain)" are highly coupled and extremely similar in their external physical manifestations.

[0004] If conventional high-pass filtering or setting fixed thresholds for alarms is used, normal high-frequency compensation actions of the flight controller can easily be misjudged as structural faults in the aircraft. How to accurately isolate complex environmental disturbances and identify hidden structural defects solely through basic external parameters without relying on internal flight control logs is a pressing technical challenge in this field. Summary of the Invention

[0005] To achieve the above-mentioned objectives, the present invention provides a data processing method for detecting low-altitude aircraft, comprising: Step S1: Synchronously acquire and output the basic timing parameter sequence, which includes triaxial acceleration, bus voltage, bus current and air pressure altitude; Step S2: Using the basic time series parameter sequence as input, calculate the smoothed dynamic characteristic variables, which include the smoothed electric power signal and dynamic acceleration signal, as well as the corresponding analytical first derivative; Step S3: Using the smoothed dynamic feature variables as input, extract the inherent physical properties of the aircraft, including the inherent system delay constant; Step S4: Based on the smoothed dynamic characteristic variables and the analytical first derivative, combined with the inherent system delay constant, calculate the transient electromechanical synchronization deviation within a given sliding time window; Step S5: Based on the transient electromechanical synchronization deviation and air pressure altitude, generate a qualitative defect and output the detection conclusion.

[0006] Furthermore, the smoothed dynamic characteristic variables are calculated, specifically including: Receives bus voltage and bus current; Calculate the original instantaneous power based on the bus voltage and bus current; Receives triaxial acceleration; The original instantaneous dynamic acceleration amplitude is calculated based on the triaxial acceleration and the gravitational acceleration constant.

[0007] Further, after calculating the original instantaneous electric power and the original instantaneous dynamic acceleration amplitude, the specific steps include: Construct a partial sliding window; A local polynomial least squares fitting algorithm is used to perform continuous smooth reconstruction of the original instantaneous electric power and the original instantaneous dynamic acceleration amplitude in the time domain; Output smoothed electrical power signal and dynamic acceleration signal; The analytical derivatives of the smoothed electric power signal and dynamic acceleration signal are obtained by analytically differentiating them, thus yielding the analytical first derivative of the corresponding smoothed polynomial.

[0008] Optionally, extract the inherent physical properties of the aircraft, specifically including: During the stable hovering phase, a smooth electric power sequence and dynamic acceleration sequence of a preset time length are extracted; Calculate the cross-correlation function based on the smoothed electric power sequence and the dynamic acceleration sequence; Extract the time delay that causes the cross-correlation function to reach its maximum value; Output the time delay and define it as an inherent system delay constant.

[0009] Optionally, the transient electromechanical synchronization deviation is calculated, specifically including: The relative rate of change of electrical energy input is obtained from the smoothed electrical power signal and its analytical first derivative; The relative rate of change of the mechanical response is obtained from the dynamic acceleration signal and its analytical first derivative; Based on the relative rate of change of electrical energy input, the relative rate of change of mechanical response, and the aforementioned inherent system delay constant, the transient electromechanical synchronization deviation is obtained within a given sliding time window.

[0010] Furthermore, based on the transient electromechanical synchronization deviation and air pressure altitude, defect qualitative analysis is performed, specifically including: The altitude derivative is obtained by taking the first-order time derivative of the barometric altitude sequence. Determine whether the absolute value of the derivative of the height is continuously less than a preset threshold within a detection period; When the judgment result is consistently less than the preset threshold, the current test condition is determined to be in the constant altitude hovering micro-disturbance test period.

[0011] Furthermore, determining that the current test condition is after the constant altitude hovering perturbation test period specifically includes: During the constant-altitude hovering perturbation test period, the transient electromechanical synchronization deviation sequence was subjected to a first-order difference operation in the time domain. Determine whether the transient electromechanical synchronization deviation exhibits a strictly monotonically increasing evolution trend over time; When it is determined that the transient electromechanical synchronization deviation exhibits a strictly monotonically increasing evolution trend, a test conclusion report is output indicating the presence of structural fatigue or mechanical transmission loosening defects.

[0012] Optionally, the basic time series parameter sequence can be acquired and output synchronously, specifically including: The basic timing parameter sequence is received in analog signal form by an externally mounted test instrument; The basic time series parameter sequence is subjected to analog-to-digital conversion and filtering preprocessing. Set a specific threshold to filter out abnormal mutation noise; The processed basic timing parameter sequence is written into a computer-readable storage medium for later use.

[0013] Furthermore, after outputting the inspection conclusion report indicating the presence of structural fatigue or loose mechanical transmission defects, the specific details include: The test results report will be formatted and encoded. The test result report, after data formatting and encoding, is sent to an external display terminal via a conventional hardware communication interface. This external display terminal provides a visual presentation and archives storage of the test results report.

[0014] To achieve the above-mentioned objectives, the present invention also provides a data processing system for low-altitude aircraft detection, which applies a data processing method for low-altitude aircraft detection as described in any of the preceding claims. The system includes: The basic data acquisition module synchronously collects and outputs a basic time series parameter sequence, which includes triaxial acceleration, bus voltage, bus current, and air pressure altitude. The dynamic feature calculation module takes the basic time series parameter sequence as input and calculates the smoothed dynamic feature variables, which include the smoothed electric power signal and dynamic acceleration signal, as well as the corresponding analytical first derivative. The inherent delay calibration module takes smooth dynamic feature variables as input and extracts the inherent physical properties of the aircraft, including the inherent system delay constant. The synchronization deviation integral module calculates the transient electromechanical synchronization deviation within a given sliding time window based on smooth dynamic characteristic variables and analytical first derivatives, combined with the inherent system delay constant. The defect characterization generation module generates defect characterization based on transient electromechanical synchronization deviation and air pressure altitude, and outputs the detection conclusion.

[0015] The beneficial effects of this plan are as follows: The advantage of this solution lies in directly addressing the industry pain point in the background technology where "normal high-frequency vibrations and current jumps generated by flight control active disturbance rejection" and "abnormal vibrations and current fluctuations caused by aircraft structural defects" are highly coupled in their external physical manifestations and difficult to separate. By calculating the "relative rate of change" and introducing delay compensation, under the condition that external wind disturbances cause changes in power and acceleration, the change rhythms of both remain synchronized under a healthy structure, and the difference after subtraction is maintained at an extremely low background noise level. Once the aircraft has micro-fastener loosening or structural fatigue cracks, new nonlinear frictional damping and gaps will be generated in the mechanical transmission chain to consume power. This abnormal hysteresis will disrupt the dynamic equilibrium, causing the relative rate of change of acceleration to lag behind the relative rate of change of electrical power, resulting in a significant increase in the difference, which accumulates with integration over a time window. Thus, complex environmental disturbances can be accurately separated in a black-box state without relying on internal flight control logs.

[0016] This scheme effectively avoids the problem of amplification of original high-frequency noise by using local polynomial smoothing differentiation technology; by using the relative rate of change difference integration mechanism, the macroscopic severe vibration caused by external wind disturbance is used as a common-mode signal to cancel it out, accurately extracting the microscopic abnormal energy hysteresis characteristics, and significantly reducing the false alarm rate in complex test environments. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating a data processing method for detecting low-altitude aircraft as described in this invention. Detailed Implementation

[0018] The present invention will now be described in detail with reference to the specific embodiments shown in the accompanying drawings. However, these embodiments do not limit the present invention, and any structural, methodological, or functional modifications made by those skilled in the art based on these embodiments are included within the scope of protection of the present invention.

[0019] If the present invention involves orientation (e.g., up, down, left, right, front, back, outside, inside, etc.) when described, then the orientations involved need to be defined.

[0020] The scope of the embodiments described herein includes the entire scope of the claims and all available equivalents thereof. Throughout this document, the terms “first,” “second,” etc., are used only to distinguish one element from another without requiring or implying any actual relationship or order between the elements. Indeed, a first element can also be referred to as a second element, and vice versa. Furthermore, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a structure, apparatus, or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a structure, apparatus, or device. Without further limitations, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the structure, apparatus, or device that includes said element. The various embodiments described herein are presented in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably.

[0021] The terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" used in this document to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings and are used only for the convenience of describing this document and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention. In the description herein, unless otherwise specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two elements, or direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0022] The data processing method and system for detecting low-altitude aircraft provided in this application will be described in detail below with reference to the accompanying drawings.

[0023] This application provides a data processing method for detecting low-altitude aircraft. First, based on the underlying architecture of this method, it includes the following steps: Step S1: Synchronously acquire and output the basic timing parameter sequence, which includes triaxial acceleration, bus voltage, bus current and air pressure altitude.

[0024] Step S2: Using the basic time series parameter sequence as input, calculate the smoothed dynamic characteristic variable, which includes the smoothed electric power signal and dynamic acceleration signal, as well as the corresponding analytical first derivative.

[0025] Step S3: Using the smoothed dynamic feature variables as input, extract the inherent physical properties of the aircraft, including the inherent system delay constant.

[0026] Step S4: Calculate the transient electromechanical synchronization deviation within a given sliding time window based on the smoothed dynamic characteristic variables and analytical first derivatives, combined with the inherent system delay constant.

[0027] Step S5: Based on the transient electromechanical synchronization deviation and air pressure altitude, generate a qualitative defect and output the detection conclusion.

[0028] As an optional embodiment, the process of calculating the smooth dynamic characteristic variables in step S2 specifically includes: receiving the bus voltage and bus current, and calculating the original instantaneous electric power based on the bus voltage and bus current; simultaneously receiving the triaxial acceleration, and calculating the original instantaneous dynamic acceleration amplitude based on the triaxial acceleration and the gravitational acceleration constant.

[0029] Furthermore, after calculating the original instantaneous electric power and the original instantaneous dynamic acceleration amplitude, in order to avoid the high-frequency electromagnetic white noise and mechanical vibration white noise contained in the original discrete sampling points being infinitely amplified during direct difference calculation, a local sliding window is constructed, and a local polynomial least squares fitting algorithm is used to continuously smooth and reconstruct the original instantaneous electric power and the original instantaneous dynamic acceleration amplitude in the time domain; the smoothed electric power signal and dynamic acceleration signal are output; the smoothed electric power signal and dynamic acceleration signal are analytically differentiated to obtain the analytical first derivative of the corresponding smoothing polynomial.

[0030] It should be noted that the parameter determination method, specific numerical range, and adaptive matching method described below are merely a preferred embodiment of this application, intended to facilitate understanding of the core technical principles of this application, and not to impose any narrow limitation on the scope of protection of this application. The specific selection of the length (number of points) of the local sliding window and the order of the local polynomial needs to be adaptively matched based on the sampling frequency of the external sensor and the expected nonlinear dynamic response bandwidth of the low-altitude aircraft.

[0031] Specifically, in order to effectively suppress high-frequency random noise while fully preserving the minute transient electromechanical differences characterizing hidden structural defects, and to avoid excessive smoothing leading to loss of physical trends or overfitting leading to derivative oscillations, the length of the local sliding window is... , Positive odd numbers and the sampling frequency of external sensors There should be specific engineering relationships between them, for example, the time span corresponding to the window. The order of the local polynomial is typically set between 0.5 and 2 times the aircraft motor control cycle or the expected pathological response cycle of the transmission chain. Meanwhile, to ensure that the analytical first derivative accurately reflects the rate of change of the signal, the order of the local polynomial is... Typically, the order is chosen between 2nd and 4th order. Those skilled in the art, based on the above principles and considering the specific testing requirements of the aircraft model and the actual signal quality, can flexibly fine-tune, optimize, or adopt other reasonable numerical combinations. Any parameter configuration scheme that can achieve continuous and smooth reconstruction of discrete signals and obtain effective first-order analytic derivatives should be included within the scope of protection of this application.

[0032] By using local polynomial fitting, discrete signals are transformed into locally smooth continuous functions and their derivatives are analytically derived. This method can accurately filter out high-frequency glitches while fully preserving the macroscopic low-frequency physical response trends caused by changes in aircraft attitude.

[0033] Specifically, in step S2, the original instantaneous electric power The calculation formula is: in, This represents the instantaneous bus voltage collected by a voltage sensor on the aircraft's power supply bus; This represents the instantaneous bus current collected on the aircraft's power supply bus by a current sensor.

[0034] The vector magnitudes of the triaxial acceleration sequences at the current sampling moment are calculated to obtain the total acceleration amplitude unaffected by the body's spatial rotation coordinate system. Then, the gravitational acceleration constant is subtracted from this total acceleration amplitude, and the absolute value is taken to remove the gravitational background, extracting the original instantaneous dynamic acceleration amplitude purely caused by mechanical vibration and dynamic abrupt changes. Original instantaneous dynamic acceleration amplitude. The calculation formula is: Optionally, to further eliminate low-frequency DC errors introduced by long-term drift and slow attitude changes, the data processing equipment calculates... Previously, it was also possible to analyze the collected data. , , The sequences are subjected to mean-removing high-pass filtering based on a sliding time window to directly extract the AC dynamic vibration components of the three axes before performing square root operations on the sum of squares. Through the above preprocessing mechanism based on vector magnitude or mean removal, this application effectively overcomes the signal distortion defect caused by the hard removal of the gravity constant on only one axis in conventional algorithms, ensuring the consistency and accuracy of electromechanical characteristic signals under complex wind disturbance and tilting conditions.

[0035] As an optional embodiment, the process of extracting the inherent physical properties of the aircraft in step S3 specifically includes: during the stable hovering phase at the initial stage of aircraft testing, extracting a smoothed electrical power sequence and a dynamic acceleration sequence of a preset time length; calculating a cross-correlation function based on the smoothed electrical power sequence and the dynamic acceleration sequence; extracting the time delay that makes the cross-correlation function reach its maximum value; and outputting this time delay and defining it as an inherent system delay constant. This delay constant comprehensively characterizes the sum of the time delays of the motor electromagnetic induction, rotor mechanical rotational inertia, and aerodynamic response in the current state of the aircraft, reflecting the inherent physical hysteresis benchmark of the system in a healthy state.

[0036] In an optional implementation, the data processing device performs mean-reduction processing on the smoothed electrical power signal and the smoothed dynamic acceleration signal respectively. Specifically, the system calculates the time average of these two signal sequences over a preset time period, and subtracts their respective average values ​​point by point from the original signal sequences to obtain a zero-mean signal component stripped of the DC background and retaining only the pure AC dynamic fluctuations. Subsequently, the system substitutes the mean-reduction AC power component and the AC acceleration component into the cross-correlation function for calculation. By adding this conventional baseline removal mechanism, it can be ensured that the cross-correlation function strictly reflects the true phase hysteresis between the perturbation fluctuations of the electrical input and the perturbation fluctuations of the mechanical response, ensuring that the extracted inherent system delay constant is accurate and reliable.

[0037] Preferably, in step S3, the system's inherent system delay constant Through the following cross-correlation function The calculation results are as follows: in, This represents the electrical power signal after local polynomial smoothing reconstruction. This represents the dynamic acceleration signal after local polynomial smoothing reconstruction. This is a time shift. It is an inherent system delay constant. That is, to make the cross-correlation function The time delay required to reach the maximum value.

[0038] As an optional embodiment, the process of calculating the transient electromechanical synchronization deviation in step S4 specifically includes: obtaining the relative rate of change of electrical energy input based on the smoothed electrical power signal and its analytical first derivative; obtaining the relative rate of change of mechanical response based on the dynamic acceleration signal and its analytical first derivative; and obtaining the transient electromechanical synchronization deviation within a given sliding time window based on the relative rate of change of electrical energy input, the relative rate of change of mechanical response, and the aforementioned inherent system delay constant.

[0039] Specifically, in step S4, the sliding time window Transient electromechanical synchronization deviation within The formula is: in, The placeholder independent variable for differentiation; For integration variables; This indicates that the time independent variable of the electric power series has been feedforward shifted. The smoothed electrical power signal afterwards; This represents its corresponding first-order analytic derivative; A smoothed dynamic acceleration signal representing the current time; This represents its corresponding first-order analytic derivative.

[0040] In the above process, the system inputs the raw timing parameters of the sensors at the bottom layer, namely voltage, current, and triaxial acceleration. These are first converted into raw instantaneous power and raw dynamic acceleration at the bottom layer, and then transformed into smooth signals and their analytical derivatives through polynomial sliding filter. During the hovering period, the inherent system delay constant is extracted through cross-correlation calculation. These intermediate physical quantities are then input together into the transient electromechanical synchronization deviation. In the calculation formula, the electric power is fed forward and compensated in the time domain. The difference between the relative rates of change of the two is calculated and integrated over a time window, finally outputting the transient electromechanical synchronization deviation sequence. This is the core determination status bit.

[0041] Furthermore, the process of generating a qualitative defect assessment based on the transient electromechanical synchronization deviation and air pressure altitude in step S5 specifically includes: processing the air pressure altitude sequence... The first-order time derivative is obtained; the absolute value of the height derivative is determined to be continuously less than a preset threshold within a detection cycle; when the result is continuously less than the preset threshold, the current test condition is determined to be in the constant-height hovering perturbation test period.

[0042] The preset threshold should be determined based on laboratory or engineering practice. One possible preset threshold is: with the detection system powered on and the aircraft stationary on the ground, the system automatically collects the static pressure-altitude derivative for a very short period (e.g., 3 seconds). The maximum absolute value of the derivative fluctuation during this period is taken, or a statistically significant value is used. The principle is to use 99.7% of the normal noise of the sensor as the preset threshold. This means that as long as the fluctuation of the vertical velocity does not exceed the physical background noise of the sensor itself, the aircraft is considered to have no vertical displacement on a macroscopic scale, that is, it is in a strict altitude hold state.

[0043] Furthermore, in an environment where the macroscopic altitude remains constant and external disturbances exist, the deviation integral value of a healthy aircraft should remain stable. If there is continuously escalating mechanical fatigue or loosening internally, energy leakage and hysteresis will gradually worsen, causing the deviation integral value to exhibit an independent monotonically increasing trend, thereby achieving accurate defect characterization. Therefore, after determining that the current test condition is in the constant altitude hovering perturbation test period, in order to accurately identify hidden structural defects, the following steps are taken: during the constant altitude hovering perturbation test period, perform a first-order time-domain difference operation on the transient electromechanical synchronization deviation sequence; determine whether the transient electromechanical synchronization deviation exhibits a strictly monotonically increasing evolution trend over time; when it is determined that the transient electromechanical synchronization deviation exhibits a strictly monotonically increasing evolution trend, output a detection conclusion report indicating the presence of structural fatigue or mechanical transmission loosening defects.

[0044] Considering that residual high-frequency oscillations in the actual sensor background and minor random disturbances in the external environment may still affect the transient electromechanical synchronization deviation index at the microscopic time step, in the above determination process, for an evolution trend exhibiting a strictly monotonically increasing trend, an option is to apply a moving average filter to the first-order difference sequence of the transient electromechanical synchronization deviation index for short-term smoothing to eliminate random jitter, and determine whether the smoothed first-order difference sequence is consistently greater than zero macroscopically. Optionally, a fault tolerance threshold can also be set. When the first-order difference of the transient electromechanical synchronization deviation sequence satisfies at least a preset proportion (e.g., 95%) of the time point values ​​within a given continuous time window that are greater than or equal to the preset fault tolerance threshold, it is determined that the transient electromechanical synchronization deviation sequence exhibits a macroscopically monotonically increasing evolution trend over time, thereby determining that the low-altitude aircraft has a loose mechanical transmission chain or structural fatigue defects. This judgment method, based on macroscopic trend fitting or statistical fault tolerance, can effectively capture the characteristics of continuous energy accumulation and deterioration caused by structural defects while filtering out random noise interference, ensuring reliable triggering of alarm conditions in real and complex physical test environments.

[0045] Optionally, for the process of synchronously acquiring and outputting the basic timing parameter sequence in step S1, in order to improve the anti-interference capability in engineering implementation, the specific steps include: receiving the basic timing parameter sequence in analog signal form through an externally mounted test instrument; performing analog-to-digital conversion and filtering preprocessing on the basic timing parameter sequence; setting a specific threshold to filter abnormal sudden noise points; and writing the processed basic timing parameter sequence into a computer-readable storage medium for later use.

[0046] Furthermore, after outputting the inspection conclusion report indicating structural fatigue or loose mechanical transmission defects, in order to achieve closed-loop interaction and recording of the inspection results, the following steps are taken: formatting and encoding the inspection conclusion report; sending the formatted and encoded inspection conclusion report to an external display terminal through a conventional hardware communication interface; and visually presenting and archiving the inspection conclusion report on the external display terminal.

[0047] In typical anticipated scenarios, such as urban sudden wind shear immunity tests, the low-altitude aircraft is assumed to be structurally sound and performs a constant altitude hovering test in a complex environment that includes urban wind shear simulation.

[0048] When the system is powered on and the aircraft is stationary on the ground, the system automatically collects the static pressure altitude derivative for 3 seconds. The maximum absolute value of the fluctuation is 0.01 m / s. According to statistics... In principle, the system automatically sets the preset threshold for height constraint to 0.03 meters per second.

[0049] During the initial stable hovering phase of the test, the system adaptively calculated the inherent system delay constant of the aircraft. Second.

[0050] Ten seconds into the test, a simulated sudden wind shear occurred. At this moment, in order to maintain altitude, the flight control system performed active wind disturbance compensation, causing the power supply bus current to surge rapidly, with the initial instantaneous power output jumping from 240 watts to 720 watts.

[0051] At the same time, due to the increased power, the three-axis acceleration of the fuselage fluctuated violently, and the original instantaneous dynamic acceleration amplitude after removing the gravitational acceleration increased from 0.1 m / s² to 3.5 m / s².

[0052] The system inputs the above data into the dynamic feature calculation module for polynomial smoothing reconstruction and analytical differentiation. The system feeds forward the time independent variable of the electric power signal by 0.05 seconds and compares it synchronously with the acceleration signal at the current time.

[0053] Because the aircraft has a healthy structure, the rate at which electrical energy is converted into mechanical energy strictly follows the inherent benchmark. At this time, the calculated relative rate of change of electrical power is highly synchronized with the relative rate of change of dynamic acceleration.

[0054] In the sliding time window The transient electromechanical synchronization deviation output after continuous integration within seconds It consistently maintains an extremely low background noise level of 0.01 to 0.02.

[0055] Meanwhile, the defect qualitative generation module performs a first-order derivative on the barometric altitude sequence. The absolute value of the altitude derivative obtained is consistently 0.015 m / s within the detection period, which is less than the preset threshold of 0.03 m / s, indicating that the current period is "fixed-altitude hovering micro-disturbance test period".

[0056] During this testing period, for The sequence undergoes a first-order difference operation in the time domain, and the difference value oscillates slightly around zero, such as +0.001 and -0.002, without showing a strictly monotonically increasing evolutionary trend.

[0057] Ultimately, the system concluded that the current high-frequency mechanical vibration and current fluctuations are normal flight control anti-disturbance actions, the aircraft structure is healthy, and no fault alarm is triggered.

[0058] In another embodiment, a hidden fastener micro-loosening defect is assumed at the arm connection of the low-altitude aircraft, and a constant altitude hovering test is performed in the same micro-turbulence simulation test environment.

[0059] When the system is powered on and at rest, The predetermined height constraint threshold, as defined in the principle, is also 0.03 m / s. The inherent system delay constant is calibrated during the initial hovering phase. Second.

[0060] During the test, micro-disturbances caused the flight control system to make high-frequency fine adjustments, resulting in fluctuations in bus current and power. The calculated relative change rate of electrical power was 0.20.

[0061] Due to microscopic loosening at the arm connection, new nonlinear frictional damping and backlash are generated in the mechanical transmission chain. When power consumption is considered as power consumption, the previously healthy state... The delay compensation mechanism is no longer able to completely offset this new abnormal lag.

[0062] This causes the relative rate of change of the mechanical response to lag on the time axis, with the calculated relative rate of change of dynamic acceleration at the corresponding time point being only 0.11.

[0063] Substituting the two sets of relative rates of change into the formula for solving the transient electromechanical synchronization deviation, the difference obtained by subtracting them is: .

[0064] As the sliding time window moves forward, the frictional work and energy leakage caused by loosening continue, and this positive difference accumulates within the time window, leading to transient electromechanical synchronization deviation in the output. It rose rapidly from 0.05 to 0.85, and then further increased to 2.10.

[0065] Meanwhile, the absolute value of the first time derivative of the air pressure altitude remained at 0.012 m / s, which was less than the preset threshold of 0.03 m / s. The system confirmed that the current operating condition was in the "constant altitude hovering perturbation test period".

[0066] During the constant-altitude hovering perturbation test period, the defect qualitative generation module... If the sequence undergoes a first-order difference operation in the time domain, and the difference result is consistently positive (e.g., +0.40, +0.65), then it is determined that... It exhibited a strictly monotonically increasing evolutionary trend over time.

[0067] Ultimately, the system successfully isolated external disturbances, made accurate qualitative analysis, and drew an execution conclusion: it output a detection conclusion report stating "structural fatigue / mechanical transmission loosening defect exists," and issued a fault warning command to the display terminal via the communication interface.

[0068] This application also provides a data processing system for low-altitude aircraft detection using the above-described data processing method, comprising: The basic data acquisition module synchronously collects and outputs a basic time series parameter sequence, which includes triaxial acceleration, bus voltage, bus current, and air pressure altitude. The dynamic feature calculation module takes the basic time series parameter sequence as input and calculates the smoothed dynamic feature variables, which include the smoothed electric power signal and dynamic acceleration signal, as well as the corresponding analytical first derivative. The inherent delay calibration module takes smooth dynamic feature variables as input and extracts the inherent physical properties of the aircraft, including the inherent system delay constant. The synchronization deviation integral module calculates the transient electromechanical synchronization deviation within a given sliding time window based on smooth dynamic characteristic variables and analytical first derivatives, combined with the inherent system delay constant. The defect characterization generation module generates defect characterization based on transient electromechanical synchronization deviation and air pressure altitude, and outputs the detection conclusion.

[0069] This application also provides an electronic terminal and a computer-readable storage medium. The electronic terminal includes a processor and a memory connected via a system bus. The memory, as a computer-readable storage medium, stores a computer program thereon.

[0070] Based on the core inventive points of this application, when the computer program in the memory is executed by the processor, the flow logic of the entire architecture can be highly condensed and summarized as follows: first, adaptive alignment and calibration of system latency, followed by cross-domain synchronous integration to remove environmental disturbances. Through this closed-loop logic, the processor can drive the efficient collaboration of various hardware modules to complete the entire data processing process, from multi-dimensional acquisition of underlying data and time-domain alignment of heterogeneous signals to precise extraction of microscopic ill-conditioning features.

[0071] The present invention can also be an apparatus, method, and / or computer program product. A computer program product may include a readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of the present invention.

[0072] Storage media can be tangible devices that hold and store instructions for use by instruction execution devices. Storage media can include, for example, electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination thereof.

[0073] It should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0074] The detailed descriptions listed above are merely specific descriptions of feasible embodiments of the present invention, and are not intended to limit the scope of protection of the present invention. All equivalent embodiments or modifications made without departing from the spirit of the present invention should be included within the scope of protection of the present invention.

Claims

1. A data processing method for detecting low-altitude aircraft, characterized in that, include: Step S1: Synchronously acquire and output the basic timing parameter sequence, which includes triaxial acceleration, bus voltage, bus current and air pressure altitude; Step S2: Using the basic time series parameter sequence as input, calculate the smoothed dynamic characteristic variables, which include the smoothed electric power signal and dynamic acceleration signal, as well as the corresponding analytical first derivative; Step S3: Using the smoothed dynamic feature variables as input, extract the inherent physical properties of the aircraft, including the inherent system delay constant; Step S4: Based on the smoothed dynamic characteristic variables and the analytical first derivative, combined with the inherent system delay constant, calculate the transient electromechanical synchronization deviation within a given sliding time window; Step S5: Based on the transient electromechanical synchronization deviation and air pressure altitude, generate a qualitative defect analysis and output the detection conclusion; The transient electromechanical synchronization deviation was calculated as follows: The relative rate of change of electrical energy input is obtained from the smoothed electrical power signal and its analytical first derivative; the relative rate of change of mechanical response is obtained from the dynamic acceleration signal and its analytical first derivative; and the transient electromechanical synchronization deviation is obtained within a given sliding time window based on the relative rate of change of electrical energy input, the relative rate of change of mechanical response, and the inherent system delay constant. The defect is qualitatively generated based on the transient electromechanical synchronization deviation and air pressure altitude, specifically as follows: The first-order time derivative of the barometric altitude sequence is obtained, and the absolute value of the altitude derivative is determined to be less than a preset threshold within a detection period. When the judgment result is consistently less than the preset threshold, the current test condition is determined to be in the constant altitude hovering micro-disturbance test period; The determination that the current test condition is after the constant altitude hovering perturbation test period is as follows: During the constant-altitude hovering perturbation test period, the transient electromechanical synchronization deviation sequence is subjected to a first-order difference operation in the time domain; it is determined whether the transient electromechanical synchronization deviation exhibits a strictly monotonically increasing evolution trend over time. When it is determined that the transient electromechanical synchronization deviation exhibits a strictly monotonically increasing evolution trend, a test conclusion report is output indicating the presence of structural fatigue or mechanical transmission loosening defects.

2. The data processing method for detecting low-altitude aircraft as described in claim 1, characterized in that, The smoothed dynamic feature variables are calculated as follows: Receive bus voltage and bus current, and calculate the original instantaneous power based on the bus voltage and bus current; It receives triaxial acceleration and calculates the original instantaneous dynamic acceleration amplitude based on the triaxial acceleration and the gravitational acceleration constant.

3. The data processing method for detecting low-altitude aircraft as described in claim 2, characterized in that, After calculating the original instantaneous electric power and the original instantaneous dynamic acceleration amplitude, the specific steps are as follows: A local sliding window is constructed, and the original instantaneous electric power and the original instantaneous dynamic acceleration amplitude are continuously smoothed and reconstructed in the time domain using a local polynomial least squares fitting algorithm. The smoothed electric power signal and dynamic acceleration signal are output. The smoothed electric power signal and dynamic acceleration signal are analytically differentiated to obtain the analytical first derivative of the corresponding smoothing polynomial.

4. The data processing method for detecting low-altitude aircraft as described in claim 1, characterized in that, Extracting the inherent physical properties of the aircraft, specifically: During the stable hovering phase, a smoothed electric power sequence and a dynamic acceleration sequence of a preset time length are extracted; a cross-correlation function is calculated based on the smoothed electric power sequence and the dynamic acceleration sequence; the time delay that makes the cross-correlation function reach its maximum value is extracted, and the time delay is output and defined as the inherent system delay constant.

5. The data processing method for low-altitude aircraft detection as described in claim 1, characterized in that, Synchronously acquire and output the basic timing parameter sequence, specifically: The basic timing parameter sequence in analog signal form is received by an externally mounted test instrument; the basic timing parameter sequence is subjected to analog-to-digital conversion and filtering preprocessing; a specific threshold is set to filter abnormal and sudden noise points; and the processed basic timing parameter sequence is written into a computer-readable storage medium for later use.

6. The data processing method for low-altitude aircraft detection as described in claim 1, characterized in that, After outputting the inspection report concluding that structural fatigue or mechanical transmission loosening defects exist, the specific details are as follows: The test results report will be formatted and encoded. The test result report, after data formatting and encoding, is sent to an external display terminal via a conventional hardware communication interface. This external display terminal provides a visual presentation and archives storage of the test results report.

7. A data processing system for detecting low-altitude aircraft, characterized in that, The data processing method for detecting low-altitude aircraft according to any one of claims 1 to 6, the system comprising: The basic data acquisition module synchronously collects and outputs a basic time series parameter sequence, which includes triaxial acceleration, bus voltage, bus current, and air pressure altitude. The dynamic feature calculation module takes the basic time series parameter sequence as input and calculates the smoothed dynamic feature variables, which include the smoothed electric power signal and dynamic acceleration signal, as well as the corresponding analytical first derivative. The inherent delay calibration module takes smooth dynamic feature variables as input and extracts the inherent physical properties of the aircraft, including the inherent system delay constant. The synchronization deviation integral module calculates the transient electromechanical synchronization deviation within a given sliding time window based on smooth dynamic characteristic variables and analytical first derivatives, combined with the inherent system delay constant. The defect characterization generation module generates defect characterization based on transient electromechanical synchronization deviation and air pressure altitude, and outputs the detection conclusion.

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