CN-121655368-B - Helicopter transmission shaft displacement test method, device, equipment and medium under airborne environment

CN121655368BCN 121655368 BCN121655368 BCN 121655368BCN-121655368-B

Abstract

The application discloses a helicopter transmission shaft displacement testing method, device, equipment and medium under an airborne environment, wherein the method comprises the steps of S1, in the running process of a helicopter power system, synchronously collecting vibration displacement signals of an eddy current displacement sensor, three-direction vibration acceleration signals of a three-way vibration acceleration sensor at a bracket and flight parameter signals, S2, establishing transmission coefficients between a test end S point of the eddy current displacement sensor and a point A of the three-way vibration acceleration sensor, constructing a transmission coefficient library under a real working condition, S3, acquiring three-way displacement signals at the S point based on the transmission coefficient library under the real working condition, and S4, combining the measured transmission shaft self size, an initial installation position and the three-way displacement signals of the eddy current displacement sensor to obtain corrected transmission shaft real displacement. The application can remove the self vibration signal component of the eddy current displacement sensor caused by the vibration of the casing during the test, obtain the actual transmission shaft displacement and improve the measurement fidelity.

Inventors

XU FUJIAN
AI XING
He Liuhai
LIU FEICHUN
ZHANG CHUNYUE
DUAN HUI
LIU CHAO

Assignees

中国航发湖南动力机械研究所

Dates

Publication Date: 20260512
Application Date: 20260203

Claims (9)

1. The helicopter transmission shaft displacement testing method in the airborne environment is characterized by comprising the following steps: s1, synchronously acquiring vibration displacement signals of an eddy current displacement sensor, three-direction vibration acceleration signals of a three-direction vibration acceleration sensor at a support of the eddy current displacement sensor and flight parameter signals of a helicopter in the running process of a helicopter power system; s2, establishing a transfer coefficient between a test end point S of the eddy current displacement sensor and a point A of a three-way vibration acceleration sensor of the eddy current displacement sensor support, linking the transfer coefficient with the real working condition of the helicopter by associating the helicopter flight parameters, and constructing a transfer coefficient library under the real working condition, wherein the method specifically comprises the following steps of: S21, in the helicopter ground bench experiment process, performing a three-way displacement test at the point S of the testing end of the eddy current displacement sensor, performing a three-way acceleration test at the point A of the eddy current displacement sensor support, obtaining a transfer coefficient matrix H from the point A to the point S, simulating different helicopter working conditions, and initially establishing a transfer coefficient library containing different working conditions Wherein the transfer coefficient H SA is: ; Wherein each element in the matrix Representing slave input ports Directing physical quantities to output ports The transmission coefficient of the directional physical quantity, ; S22, synchronously acquiring a three-way acceleration signal of the eddy current displacement sensor bracket, a three-way displacement signal at the test end S point of the eddy current displacement sensor and a helicopter flight parameter signal under the real working condition of the helicopter power system; S23, performing data processing by adopting a signal analysis method with high time-frequency resolution, then performing time-frequency filtering to eliminate the influence of interference noise, extracting the main-order time-frequency ridge amplitude of the transmission shaft to be tested under the real working condition, and accurately capturing transient characteristics; S24, dividing the same-order time-frequency ridge line to obtain a transmission coefficient under the corresponding frequency, and smoothing the transmission coefficient to eliminate interference; S25, associating the transfer coefficient with a helicopter flight parameter signal, associating the transfer coefficient with a real working condition of the helicopter, and constructing a transfer coefficient library under the real working condition; s3, acquiring a three-way displacement time domain signal at the S point of the testing end of the eddy current displacement sensor based on a transfer coefficient library under a real working condition, and taking the three-way displacement time domain signal as a three-way displacement signal of the eddy current displacement sensor; S4, correcting the vibration displacement signal of the eddy current displacement sensor by combining the size of the transmission shaft to be measured, the initial installation position and the three-way displacement signal of the eddy current displacement sensor to obtain the corrected real displacement of the transmission shaft.
2. The method for testing the displacement of the transmission shaft of the helicopter in the airborne environment according to claim 1 is characterized in that different helicopter working conditions comprise slow ground, slow air, hovering, flat flight, climbing, steering and diving, and the signal analysis method with high time-frequency resolution comprises a synchronous compression wave reduction conversion method and a parameterized time-frequency analysis method.
3. The method for testing displacement of a transmission shaft of a helicopter in an airborne environment according to claim 2, wherein said step S3 specifically comprises the steps of: s31, synchronous compression wavelet transformation is carried out on three-direction vibration acceleration signals of the collected three-direction vibration acceleration sensor, relevant fundamental frequency of a detected shaft and a frequency multiplication ridge line thereof are extracted, noise and interference are eliminated, and transient characteristic information is reserved; s32, utilizing the helicopter flight parameter signals to acquire flight parameter information at any time in the synchronous compression wavelet transformation time-frequency matrix, thereby correlating the transmission coefficients of corresponding fundamental frequency and frequency multiplication amplitude thereof in the transmission coefficient library Obtaining relevant displacement transfer frequency and frequency multiplication amplitude information of the test end S point of the eddy current displacement sensor, and obtaining a displacement time-frequency matrix of the test end S point of the eddy current displacement sensor: ; wherein f=kf r ,f r is the rotation frequency of the transmission shaft to be measured, and k is a positive integer; , Representing time-frequency matrixes in three directions; The time-frequency ridge line amplitude extracted in the signal synchronous compression transformation is used for the time-frequency ridge line amplitude; Is that Is used for the synchronous compression wavelet transform of (a), ; S33, carrying out synchronous compression wavelet inverse transformation on a displacement time-frequency signal at the S point of the testing end of the eddy current displacement sensor, so as to obtain a three-way displacement time-domain signal at the S point of the testing end of the eddy current displacement sensor as a three-way displacement signal of the eddy current displacement sensor: ; Wherein, the , Representing displacement time domain signals of three directions at the test end S point of the eddy current displacement sensor, The inverse transform calculation is compressed for synchronization.
4. The method for testing displacement of a transmission shaft of a helicopter in an airborne environment according to claim 3, wherein said step S4 specifically comprises the steps of: s41, considering the displacement correction of the Z direction of the eddy current displacement sensor, namely calculating the gap variation of the probe of the eddy current displacement sensor and the measured transmission shaft according to the displacement of the eddy current displacement sensor in the Z direction : ; Wherein R is the radius of a transmission shaft, θ is an included angle formed by the z-direction movement of the eddy current displacement sensor: ; S42, considering the displacement correction of the eddy current displacement sensor in the X direction, namely, the movement of the eddy current displacement sensor in the X direction and the same-direction axis of the collected vibration displacement signal X (t) of the eddy current displacement sensor are considered, and the collected vibration displacement signal X (t) of the eddy current displacement sensor is directly subtracted from the X three-way displacement signal of the eddy current displacement sensor ; S43, considering the displacement correction of the y direction of the eddy current displacement sensor, wherein when the eddy current displacement sensor moves in the y direction, the sensor displacement probe moves parallel to the transmission shaft, and the influence of the y direction movement of the eddy current displacement sensor on the collected vibration displacement signal of the eddy current displacement sensor is equivalent to that of the sensor displacement probe; S44, correcting the clearance variation delta between the probe of the eddy current displacement sensor and the measured transmission shaft according to the x-direction displacement and the z-direction displacement of the eddy current displacement sensor to obtain the real displacement of the transmission shaft.
5. The method for testing displacement of a propeller shaft of a helicopter in an on-board environment according to claim 4, wherein said step S44 comprises the steps of: S441, obtaining corrected transmission shaft real displacement according to the self x-direction and z-direction displacement of the eddy current displacement sensor The method comprises the following steps: 。
6. the method for testing displacement of a transmission shaft of a helicopter in an on-board environment according to claim 5, wherein said step S44 comprises the steps of: s441, obtaining a corrected displacement synchronous compression wavelet transform time-frequency matrix through synchronous compression wavelet transform and ridge line amplitude extraction : ; Wherein, the Vibration displacement signal of eddy current displacement sensor The amplitude of the time-frequency ridge line extracted by synchronous compression wavelet transformation is f=kf r ,f r , the frequency of the transmission shaft to be measured is converted, and k is a positive integer; S442, pair of Performing synchronous compression wavelet change inverse transformation to obtain corrected transmission shaft true displacement : ; Wherein, the The inverse transform calculation is compressed for synchronization.
7. Helicopter transmission shaft displacement testing arrangement under airborne environment, its characterized in that includes: the data acquisition module is used for synchronously acquiring vibration displacement signals of the eddy current displacement sensor, vibration acceleration signals of the three-way vibration acceleration sensor at the support of the eddy current displacement sensor and flight parameter signals of the helicopter in the running process of the helicopter power system; The transfer coefficient library construction module is used for establishing transfer coefficients between a test end point S of the eddy current displacement sensor and a three-way vibration acceleration sensor point A of the eddy current displacement sensor support, linking the transfer coefficients with the real working condition of the helicopter by associating the helicopter flight parameters, and constructing a transfer coefficient library under the real working condition, and is specifically used for: In the helicopter ground bench experiment process, three-way displacement test is conducted at the S point of the test end of the eddy current displacement sensor, three-way acceleration test is conducted at the A point of the eddy current displacement sensor support, a transfer coefficient matrix H from the A point to the S point is obtained, different helicopter working conditions are simulated, and a transfer coefficient library containing different working conditions is initially built Wherein the transfer coefficient H SA is: ; Wherein each element in the matrix Representing slave input ports Directing physical quantities to output ports The transmission coefficient of the directional physical quantity, ; Under the real working condition of the helicopter power system, synchronously acquiring a three-way acceleration signal of the eddy current displacement sensor bracket, a three-way displacement signal at the test end S point of the eddy current displacement sensor and a helicopter flight parameter signal; Carrying out data processing by adopting a signal analysis method with high time-frequency resolution, then carrying out time-frequency filtering to eliminate the influence of interference noise, extracting the main-order time-frequency ridge amplitude of a transmission shaft to be tested under the real working condition, and accurately capturing transient characteristics; dividing the same-order time-frequency ridge line to obtain a transmission coefficient under the corresponding frequency, and smoothing the transmission coefficient to eliminate interference; Associating the transfer coefficient with a helicopter flight parameter signal, associating the transfer coefficient with a real working condition of the helicopter, and constructing a transfer coefficient library under the real working condition; The three-dimensional displacement signal calculation module is used for acquiring a three-dimensional displacement time domain signal at the S point of the testing end of the eddy current displacement sensor based on a transfer coefficient library under a real working condition to serve as a three-dimensional displacement signal of the eddy current displacement sensor; The displacement correction module is used for correcting the vibration displacement signal of the eddy current displacement sensor by combining the size of the transmission shaft to be measured, the initial installation position and the three-way displacement signal of the eddy current displacement sensor to obtain the corrected real displacement of the transmission shaft.
8. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor, when executing the computer program, implements the steps of the helicopter propeller shaft displacement test method in an on-board environment as claimed in any one of claims 1 to 6.
9. A storage medium comprising a stored program, characterized in that the device in which the storage medium is controlled to perform the steps of the helicopter transmission shaft displacement testing method in an on-board environment according to any one of claims 1 to 6 when the program is run.

Description

Helicopter transmission shaft displacement test method, device, equipment and medium under airborne environment Technical Field The application relates to the technical field of helicopter transmission shaft testing, in particular to a method, a device, equipment and a medium for testing displacement of a helicopter transmission shaft in an airborne environment. Background The propeller shaft is a critical component of the helicopter power system, the operation of which is directly related to the safety of the aircraft. In order to monitor the status of the drive shaft in an on-board environment, to evaluate the operational health status of the drive shaft, it is necessary to test the drive shaft displacement. At present, an eddy current displacement sensor is directly and fixedly installed on an engine or a transmission system casing to test a transmission shaft displacement signal. Various rotary excitation sources exist in the running process of the helicopter power system, the vibration environment is bad, and the vibration response is complex. The eddy current sensor can generate corresponding vibration displacement under the influence of self vibration of the helicopter power system casing, and the vibration response component of the casing is inevitably superposed in the tested transmission shaft displacement signal to influence the authenticity of the transmission shaft displacement signal. To accurately test the drive shaft displacement, the influence of vibration of the eddy current sensor itself caused by vibration of the casing must be removed. As shown in fig. 1, in the prior art, since the eddy current sensor bracket is directly fixed on the casing of the power system, the sensor itself can vibrate along with the casing at the same time, and the vibration displacement signal X (t) tested reflects the vibration displacement of the transmission shaft vibration displacement superposition sensor itself. During data processing, the peak-to-peak value of the displacement signal is directly selected as the displacement of the transmission shaft, so that errors are obvious. Due to the complexity of an airborne vibration environment and the limitation of the structural space of the helicopter, the eddy current displacement sensor cannot be directly installed on a static platform, so that the reality of a displacement monitoring result of a transmission shaft of the helicopter system is low. Disclosure of Invention The application provides a helicopter transmission shaft displacement testing method in an airborne environment, which is used for solving the technical problem that the reality of a helicopter transmission shaft displacement testing result in the existing airborne environment is low. The application is realized by the following scheme: The displacement testing method for the helicopter transmission shaft under the airborne environment comprises the following steps: s1, synchronously acquiring vibration displacement signals of an eddy current displacement sensor, three-direction vibration acceleration signals of a three-direction vibration acceleration sensor at a support of the eddy current displacement sensor and flight parameter signals of a helicopter in the running process of a helicopter power system; s2, establishing a transfer coefficient between a test end point S of the eddy current displacement sensor and a three-way vibration acceleration sensor point A of the eddy current displacement sensor bracket, and connecting the transfer coefficient with the real working condition of the helicopter by associating the helicopter flight parameters to construct a transfer coefficient library under the real working condition; s3, acquiring a three-way displacement time domain signal at the S point of the testing end of the eddy current displacement sensor based on a transfer coefficient library under a real working condition, and taking the three-way displacement time domain signal as a three-way displacement signal of the eddy current displacement sensor; S4, correcting the vibration displacement signal of the eddy current displacement sensor by combining the size of the transmission shaft to be measured, the initial installation position and the three-way displacement signal of the eddy current displacement sensor to obtain the corrected real displacement of the transmission shaft. Further, the step S2 specifically includes the steps of: S21, in the helicopter ground bench experiment process, performing a three-way displacement test at the point S of the testing end of the eddy current displacement sensor, performing a three-way acceleration test at the point A of the eddy current displacement sensor support, obtaining a transfer coefficient matrix H from the point A to the point S, simulating different helicopter working conditions, and initially establishing a transfer coefficient library containing different working conditions Wherein the transfer coefficient H SA is: ; Wherein each eleme