Helicopter flight vibration data processing and classifying method and device

Abstract

The invention belongs to the field of helicopter vibration data processing, and relates to a helicopter flight vibration data processing and classifying method and device. The method comprises the following steps: collecting flight vibration data of each measuring point position of a helicopter; classifying the helicopter flight vibration data according to the helicopter flight spectrum to determine the flight state of the vibration response; classifying the flight vibration data according to the vibration environment requirement of the helicopter to determine the influence of different vibration sources of the helicopter on the position of the measuring point; for the same measuring point position, processing the flight vibration data of the measuring point position, and obtaining vibration responses of the measuring point position under the concerned vibration source in different flight states according to the flight spectrum; and analyzing the obtained vibration response, analyzing the vibration response condition of each part of the helicopter in combination with a full-helicopter transfer function test and a component dynamic characteristic test, judging the accuracy and rationality of the vibration response of the helicopter body, and analyzing the full-helicopter flight vibration level of the helicopter in combination with a helicopter dynamics theory.

Description

Technical Field

[0001] The invention belongs to the field of helicopter vibration data processing, and relates to a method and device for processing and classifying helicopter flight vibration data. Background Art

[0002] The vibration environment of helicopters is worse than that of other aircraft due to their unique hovering, sideways and inverted flight capabilities. The vibration of conventional helicopters comes from the main rotor, tail rotor, reducer gear meshing and transmission system. It is very necessary to measure the vibration response of key parts during the scientific research test flight stage. On the one hand, the vibration conditions at key locations can be used to monitor whether the components are abnormal, and on the other hand, a vibration environment spectrum can be provided for the onboard equipment. Reasonable vibration data processing and classification ensure the rationality of the onboard vibration response results, providing support for flight safety and vibration environment spectrum. Summary of the invention

[0003] The purpose of the present invention is to propose a method for processing and classifying helicopter flight vibration data to meet the requirements of engineering design and application.

[0004] The technical solution is:

[0005] In a first aspect, a method for processing and classifying helicopter flight vibration data is provided, comprising:

[0006] Collect flight vibration data at each measuring point of the helicopter;

[0007] Classify the helicopter flight vibration data according to the helicopter flight spectrum to determine the flight state in which the vibration response is located;

[0008] Classify the flight vibration data according to the helicopter vibration environment requirements to determine the impact of different vibration sources of the helicopter on the measurement point location;

[0009] For the same measuring point, the flight vibration data of the measuring point is processed, and the vibration response of the measuring point under the vibration source of interest under different flight conditions is obtained according to the flight spectrum;

[0010] The obtained vibration response is analyzed, and the vibration response of each part of the helicopter is analyzed in combination with the whole-machine transfer function test and component dynamic characteristics test to judge the accuracy and rationality of the airframe vibration response, and the whole-machine flight vibration level of the helicopter is analyzed in combination with the helicopter dynamics theory.

[0011] Furthermore, the helicopter flight vibration data is classified according to the helicopter flight spectrum to determine the flight state of the vibration response, including:

[0012] By referring to the helicopter flight spectrum, the vibration data of all flights during the flight are statistically analyzed according to the flight status under specific conditions, and the distribution of helicopter flight status under all flights is obtained;

[0013] The flight vibration data are segmented according to the distribution of helicopter flight status under all flight sorties.

[0014] Furthermore, the flight vibration data is classified according to the helicopter vibration environment requirements to determine the impact of different vibration sources of the helicopter on the measurement point location, including:

[0015] With reference to the relevant content of the helicopter vibration environment, the area where the measuring points are located is divided into the main reducer measuring point area, the cockpit vibration measuring point area, and the transmission shaft measuring point area, so as to realize the classification of the flight vibration data.

[0016] Furthermore, for the same measuring point, the flight vibration data of the measuring point is processed, and the vibration response of the measuring point under the vibration source of interest under different flight conditions is obtained according to the flight spectrum, including:

[0017] The flight vibration data of different areas are subjected to Fourier transform FFT to obtain the vibration response of the measuring point under the vibration source of interest under different flight conditions.

[0018] In a second aspect, a device for processing and classifying helicopter flight vibration data is provided, comprising:

[0019] The acquisition module is used to collect the flight vibration data of each measuring point of the helicopter;

[0020] The classification module is used to classify the helicopter flight vibration data according to the helicopter flight spectrum to determine the flight state of the vibration response; it is also used to classify the flight vibration data according to the helicopter vibration environment requirements to determine the influence of different vibration sources of the helicopter on the measurement point location;

[0021] A processing module is used to process the flight vibration data of the same measuring point position, and obtain the vibration response of the measuring point position under the vibration source of interest under different flight conditions according to the flight spectrum;

[0022] The analysis and judgment module is used to analyze the obtained vibration response, analyze the vibration response of each part of the helicopter in combination with the whole-machine transfer function test and component dynamic characteristics test, judge the accuracy and rationality of the body vibration response, and analyze the flight vibration level of the whole helicopter in combination with helicopter dynamics theory.

[0023] Furthermore, the induction module is specifically used for:

[0024] By referring to the helicopter flight spectrum, the vibration data of all flights during the flight are statistically analyzed according to the flight status under specific conditions, and the distribution of helicopter flight status under all flights is obtained;

[0025] The flight vibration data are segmented according to the distribution of helicopter flight status under all flight sorties.

[0026] Furthermore, the induction module is specifically used for:

[0027] With reference to the relevant content of the helicopter vibration environment, the area where the measuring points are located is divided into the main reducer measuring point area, the cockpit vibration measuring point area, and the transmission shaft measuring point area, so as to realize the classification of the flight vibration data.

[0028] Furthermore, the processing module is specifically used for:

[0029] The flight vibration data of different areas are subjected to Fourier transform FFT to obtain the vibration response of the measuring point under the vibration source of interest under different flight conditions. DETAILED DESCRIPTION

[0030] A method for processing and classifying helicopter flight vibration data, the specific steps of the method are as follows.

[0031] Step 1: Collect helicopter flight vibration data and flight parameter data

[0032] The vibration response at different positions of the aircraft body is collected through the onboard equipment. The commonly used vibration sensor is a piezoelectric sensor. In order to better process the collected vibration data and flight parameter data, the data storage format is agreed to be as follows. The original signal data (after A / D conversion) is stored in binary (or decimal) format, and the channel number, data type, data unit and other information are noted in text form. The data storage format is as follows.

[0033] Table 1 Data storage format

[0034] Data parameter 1 Data parameter 2 …… The first sample Floating point type (4 bytes) Floating point type (4 bytes) Floating point type (4 bytes) Sample 2 Floating point type (4 bytes) Floating point type (4 bytes) Floating point type (4 bytes) …… …… …… …… The Nth sample Floating point type (4 bytes) Floating point type (4 bytes) Floating point type (4 bytes)

[0035] Step 2: Classification of helicopter flight vibration data

[0036] 1. Classification of vibration data and flight parameter data based on helicopter flight status

[0037] It can be known from the helicopter dynamics theory that the flight state of the helicopter determines the magnitude and direction of the hub force, and directly determines the vibration response of the helicopter vibration measurement point. Referring to the helicopter flight spectrum, the vibration data of all flight sorties during the helicopter flight are statistically analyzed according to the flight state under certain conditions, and the distribution of the helicopter flight state under all flight sorties is obtained. The helicopter flight dynamics theory points out that the flight state of the helicopter can be characterized by the flight speed, flight altitude, flight weight center, pitch angle, roll angle and heading angle of the helicopter. The above parameters are selected to characterize the flight state of the helicopter. The specific information is shown in Table 2.

[0038] Table 2 Flight status judgment diagram

[0039]

[0040] According to the flight status judgment diagram, the state of the aircraft is judged by a self-written program, and the flight status matrix FS is obtained as follows;

[0041]

[0042] t is represents the start time of the i-th flight state, t id represents the end time of the i-th flight state, Sti represents the relevant parameters of the helicopter in the i-th flight state, and is composed of the flight parameters in Table 2.

[0043] Furthermore, the vibration data of all helicopter flights are processed through the flight state matrix FS to obtain the vibration data matrix set VDi under the corresponding flight state.

[0044]

[0045] Where m represents the length of the vibration time domain signal, n represents the channel of the measuring point on the machine, P = Fs*(t id -t is ), Fs is the sampling rate, VD i Represents the time domain signal of the vibration data corresponding to the i-th flight state.

[0046] 2. Classification of flight vibration data based on the vibration source impact area

[0047] The vibration of the helicopter body is affected by multiple vibration sources on the aircraft at the same time, and it shows the characteristics of multiple frequencies acting simultaneously in the frequency domain of the helicopter measurement point. However, the influence of each vibration source is different in different areas of the helicopter. Referring to the relevant requirements of the helicopter vibration environment, the area where the helicopter vibration measurement points are located is divided into the main reducer area measurement point, the cockpit vibration area measurement point, the transmission shaft area measurement point, the engine area measurement point and the helicopter tail area measurement point. According to the location of the measurement point, the time domain signal of the measurement point is classified and divided. In different measurement point areas, refer to the requirements of the helicopter vibration environment and select the appropriate vibration source frequency as the frequency point for frequency domain analysis.

[0048] Step 3: Processing and analyzing the classified helicopter flight vibration data

[0049] After classifying the helicopter flight vibration data in step 2, the vibration time domain signals of each measuring point in all flight states in different regions are obtained.

[0050]

[0051] Where P = Fs*(t id -t is ), Fs is the sampling rate, VD ij represents the vibration data time domain signal corresponding to the ith flight state in the jth region. Fj represents the considered vibration source frequency in the jth region.

[0052] 1. Flight vibration data processing based on fast FFT calculation

[0053] First, the classified flight vibration signals are processed by fast FFT to obtain the vibration response Fr of different measurement points in different regions under different flight conditions. i .

[0054]

[0055] Fr i Represents the vibration response corresponding to the i-th flight state.

[0056] 2. Dynamic analysis based on vibration response of frequency domain measurement points

[0057] First, in order to analyze the flight vibration level of the entire helicopter, the vibration responses at different measuring points were analyzed. Based on the helicopter dynamics theory, the vibration responses of measuring points in different regions at different frequencies were analyzed as the flight speed changed, and the correlation between the vibration responses of measuring points at different frequencies and the flight speed was obtained.

[0058] Secondly, in order to analyze the correlation between the helicopter blade load and the body vibration response, the correlation between the body vibration and the main blade load was analyzed through the measuring points in the main reducer area, and the correlation between the measuring point vibration and the tail rotor blade load was analyzed through the measuring points in the tail area. The relationship between the blade load and the body vibration was obtained, providing a basis for flight safety monitoring.

[0059] Furthermore, the accuracy and rationality of the vibration response of the helicopter body are judged by combining the results of the whole-machine transfer function test and component dynamic characteristics test with the vibration response of the corresponding parts of the helicopter.

[0060] Finally, the vibration response values ​​at different vibration source frequencies in different areas are statistically analyzed to correct the values ​​of the helicopter vibration environment technical requirements and provide a reasonable vibration environment spectrum for the onboard equipment.

Claims

1. A method for processing and classifying helicopter flight vibration data, characterized in that: include: Collect flight vibration data at each measuring point of the helicopter; Classify the helicopter flight vibration data according to the helicopter flight spectrum to determine the flight state in which the vibration response is located; Classify the flight vibration data according to the helicopter vibration environment requirements to determine the impact of different vibration sources of the helicopter on the measurement point location; For the same measuring point, the flight vibration data of the measuring point is processed, and the vibration response of the measuring point under the vibration source of interest under different flight conditions is obtained according to the flight spectrum; The obtained vibration response is analyzed, and the vibration response of each part of the helicopter is analyzed in combination with the whole-machine transfer function test and component dynamic characteristics test to judge the accuracy and rationality of the airframe vibration response, and the whole-machine flight vibration level of the helicopter is analyzed in combination with the helicopter dynamics theory.

2. The method according to claim 1, characterized in that The helicopter flight vibration data is classified according to the helicopter flight spectrum to determine the flight state of the vibration response, including: By referring to the helicopter flight spectrum, the vibration data of all flights during the flight are statistically analyzed according to the flight status under specific conditions, and the distribution of helicopter flight status under all flights is obtained; The flight vibration data are segmented according to the distribution of helicopter flight status under all flight sorties.

3. The method according to claim 2, characterized in that The flight vibration data is classified according to the helicopter vibration environment requirements to determine the impact of different vibration sources of the helicopter on the measurement point location, including: With reference to the relevant content of the helicopter vibration environment, the area where the measuring points are located is divided into the main reducer measuring point area, the cockpit vibration measuring point area, and the transmission shaft measuring point area, so as to realize the classification of the flight vibration data.

4. The method according to claim 3, characterized in that For the same measuring point, the flight vibration data of the measuring point is processed, and the vibration response of the measuring point under the vibration source of interest under different flight conditions is obtained according to the flight spectrum, including: The flight vibration data of different areas are subjected to Fourier transform FFT to obtain the vibration response of the measuring point under the vibration source of interest under different flight conditions.

5. A device for processing and classifying helicopter flight vibration data, characterized in that: include: The acquisition module is used to collect the flight vibration data of each measuring point of the helicopter; The classification module is used to classify the helicopter flight vibration data according to the helicopter flight spectrum to determine the flight state of the vibration response; it is also used to classify the flight vibration data according to the helicopter vibration environment requirements to determine the influence of different vibration sources of the helicopter on the measurement point location; A processing module is used to process the flight vibration data of the same measuring point position, and obtain the vibration response of the measuring point position under the vibration source of interest under different flight conditions according to the flight spectrum; The analysis and judgment module is used to analyze the obtained vibration response, analyze the vibration response of each part of the helicopter in combination with the whole-machine transfer function test and component dynamic characteristics test, judge the accuracy and rationality of the body vibration response, and analyze the flight vibration level of the whole helicopter in combination with helicopter dynamics theory.

6. The device according to claim 5, characterized in that Induction module, specifically used for: By referring to the helicopter flight spectrum, the vibration data of all flights during the flight are statistically analyzed according to the flight status under specific conditions, and the distribution of helicopter flight status under all flights is obtained; The flight vibration data are segmented according to the distribution of helicopter flight status under all flight sorties.

7. The device according to claim 6, characterized in that Induction module, specifically used for: With reference to the relevant content of the helicopter vibration environment, the area where the measuring points are located is divided into the main reducer measuring point area, the cockpit vibration measuring point area, and the transmission shaft measuring point area, so as to realize the classification of the flight vibration data.

8. The device according to claim 7, characterized in that Processing module, specifically used for: The flight vibration data of different areas are subjected to Fourier transform FFT to obtain the vibration response of the measuring point under the vibration source of interest under different flight conditions.

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