Helicopter rotor vibration detection system and method

Abstract

The invention discloses a helicopter rotor vibration detection system, which comprises a helicopter rotor, a reader and a plurality of sensing tags, the sensing tags are all passive radio frequency tags, the sensing tags are arranged on the helicopter rotor, the reader can collect phase signals of the sensing tags, and then vibration characteristics of the helicopter rotor are extracted through the phase signals of the sensing tags; the helicopter rotor wing is further provided with a calibration tag, the calibration tag is also a passive radio frequency tag, the geometric center of the calibration tag coincides with the rotation center of the helicopter rotor wing, and the reader can collect phase signals of the calibration tag. According to the method, the abnormal vibration state of the helicopter rotor wing can be recognized, and the motion form of the helicopter rotor wing can be judged.

Description

Technical Field

[0001] The present invention relates to the technical field of helicopter rotor vibration monitoring, and particularly to a helicopter rotor vibration detection system and method. Background Art

[0002] The helicopter rotor is a key flight component in the aerospace field and is widely used in the flight control systems of civil and military helicopters. During flight, the rotor undergoes complex flapping vibrations and torsional vibrations, which have important effects on the rotor's performance, structural safety, and flight stability. Traditional rotor vibration monitoring methods usually rely on complex sensor arrangements and a large number of cable connections, which not only increase the difficulty of installation and maintenance but may also have an adverse impact on the rotor's dynamic performance. In addition, traditional vibration monitoring systems often require the installation of expensive and complex wired sensors, which may need to be maintained regularly and are restricted by the rotor's movement, making it difficult to adapt to efficient real-time applications. Currently, there is no convenient and effective reliable solution for detecting the motion state of helicopter rotors. Therefore, for helicopter rotor vibration monitoring, it is urgent to develop a more efficient, convenient, and low-cost solution. Summary of the Invention

[0003] Object of the Invention: In order to overcome the deficiencies in the prior art, the present invention provides a helicopter rotor vibration detection system and method, aiming to identify the abnormal vibration state of the helicopter rotor and determine its motion form.

[0004] Technical Solution: To achieve the above object, a helicopter rotor vibration detection system of the present invention includes a helicopter rotor, a reader, and a plurality of sensing tags; all the sensing tags are passive radio frequency tags, the sensing tags are arranged on the helicopter rotor, the reader can collect the phase signals of the sensing tags, and then extract the vibration characteristics of the helicopter rotor through the phase signals of the sensing tags; a calibration tag is also arranged on the helicopter rotor, the calibration tag is also a passive radio frequency tag, and the geometric center of the calibration tag coincides with the rotation center of the helicopter rotor, and the reader can collect the phase signal of the calibration tag.

[0005] Further, the plurality of sensing tags are divided into a flapping vibration sensing tag array and a torsional vibration sensing tag array. Each sensing tag in the flapping vibration sensing tag array is arranged on the axis of the helicopter rotor, and each sensing tag in the torsional vibration sensing tag array is respectively arranged on both side edges of the helicopter rotor.

[0006] Further, the sensing tag near the end of the helicopter rotor is an anti - centrifugal force tag. The anti - centrifugal force tag is pasted under the helicopter rotor, and a slightly convex airfoil profile is formed on the lower surface of the anti - centrifugal force tag. When the air flow passes through the airfoil profile on the lower surface of the anti - centrifugal force tag, an upward acting force is generated on the anti - centrifugal force tag, enabling the anti - centrifugal force tag to overcome the centrifugal force and tightly adhere to the end of the helicopter rotor.

[0007] Further, a detection method for a helicopter rotor vibration detection system includes the following steps: Step S1: Arrange sensing tags and calibration tags on the helicopter rotor; Step S2: Rotate the helicopter rotor and synchronously collect the phase signals of all the arranged tags; Step S3: Combine the phase signals of the calibration tags to perform synchronous dynamic calibration on the phase signals of the sensing tags; Step S4: Perform compressive sensing processing on the synchronously dynamically calibrated phase signals to reconstruct the phase signals; Step S5: Perform phase unwrapping processing on the phase signals after compressive sensing processing; Step S6: Extract the flapping vibration characteristic signals and torsional vibration characteristics of the helicopter rotor from the unwrapped phase signals.

[0008] Further, in Step S1, arrange calibration tags at the rotation center of the helicopter rotor, and arrange sensing tags on the axis and both sides of the helicopter rotor to form a flapping vibration sensing tag array and a torsional vibration sensing tag array respectively.

[0009] In Step S2, the phase signal change of the sensing tag is:

[0010]

[0011] where λ is the wavelength of the electromagnetic wave in the communication frequency band; is the fixed phase offset introduced by the hardware; is the phase offset introduced by the tag's self - rotation: dAP is the change in the distance between the tag and the reader antenna, and dAP satisfies the following formula:

[0012]

[0013] where r is the distance between the geometric center of the measured passive RF tag and the rotation center of the helicopter rotor; α is the angle turned by the passive RF tag; L is the distance between the geometric center of the measured passive RF tag and the reader antenna in the z - axis direction; X2 and Y2 are the coordinates of the reader antenna in the three - dimensional coordinate system respectively. The phase signal change of the calibration tag is:

[0014]

[0015] where n is the rotational speed of the helicopter rotor.

[0016] Further, in step S3, since the sensing tag rotates with the helicopter rotor and also rotates on its own axis, the phase signal of the calibration tag is subtracted from the phase signal of each sensing tag to synchronously and dynamically calibrate the phase signal of the sensing tag.

[0017] Further, in step S4, the process of compressive sensing processing for the phase signal of the sensing tag includes: selecting an appropriate transformation matrix, constructing an observation matrix, and performing optimization and solution by minimizing the norm, and finally restoring and reconstructing the phase signal.

[0018] Further, in step S5, the phase signal after compressive sensing reconstruction is stored separately; then the difference between every two adjacent phase points is calculated; a threshold is set, and if the phase difference exceeds the threshold, it is considered that a phase jump occurs; if a jump occurs between adjacent phase values, the latter phase value is adjusted to eliminate the jump; after correction, if there is still a jump, continue to correct; if there is no jump, the unwrapping process ends; the condition for the end of the unwrapping is that all phase differences are within the threshold range.

[0019] Further, step S6 specifically includes the following steps: Step S6.1: Perform Fourier transform on the calibration tag to obtain the rotational frequency information of the helicopter rotor's rotational motion; Step S6.2: Perform band-stop filtering on the signal after phase unwrapping of the flapping vibration sensing tag to filter out the rotational frequency and its harmonic signals obtained in step S6.1 to extract the flapping vibration characteristic signal of the helicopter rotor; Step S6.3: Perform band-stop filtering on the signal after phase unwrapping of the torsional vibration sensing tag to filter out the rotational frequency and its harmonic signals obtained in step S6.1, as well as the flapping vibration frequency signal obtained in step S6.2, so as to obtain the torsional vibration characteristic signal of the helicopter rotor.

[0020] Advantageous effects: A helicopter rotor vibration detection system and method of the present invention has the following advantageous effects:

[0021] 1) Using passive radio frequency tags to accurately detect the vibration characteristic signals of helicopter rotors, having the advantages of passive wireless non-contact detection, and avoiding the limitations of traditional wired sensors that cannot be installed.

[0022] 2) By arranging the flapping vibration sensing tag array at the axis of the helicopter rotor, the interference of torsional vibration on the phase signal can be effectively reduced, and based on the flapping vibration characteristics of this tag, the torsional vibration characteristics in the phase signal of the torsional vibration sensing tag can be accurately extracted through band-stop filtering.

[0023] 3) The sensing tag near the end of the helicopter rotor is an anti - centrifugal force tag, and a slightly convex airfoil profile is formed on the lower surface of the anti - centrifugal force tag; when the air flow passes through the airfoil profile, an upward acting force is generated, enabling the anti - centrifugal force tag to overcome the centrifugal force and adhere tightly to the end of the helicopter rotor, making it difficult for the anti - centrifugal force tag to fall off from the end of the helicopter rotor. Brief Description of the Drawings

[0024] Attached Figure 1 is a schematic structural diagram of a helicopter rotor;

[0025] Attached Figure 2 is a schematic layout diagram of the tags on the helicopter rotor;

[0026] Attached Figure 3 is a flowchart of the detection method of the helicopter rotor vibration detection system;

[0027] Attached Figure 4 is a time - domain and frequency - domain diagram of the phase information of the sensing tag observed by the reader;

[0028] Attached Figure 5 is a phase change diagram of the calibration tag rotating one week;

[0029] Attached Figure 6 is an unwrapping effect diagram when the unwrapping algorithm uses different thresholds with a sampling frequency of 100 read / s;

[0030] Attached Figure 7 is an unwrapping effect diagram when the unwrapping algorithm uses different thresholds with a sampling frequency of 1000 read / s after compressive sensing;

[0031] Attached Figure 8 is an effect diagram of extracting the characteristic signal after filtering processing. Detailed Embodiment

[0032] The present invention will be further described below in conjunction with the accompanying drawings.

[0033] As attached Figures 1 to 8 A helicopter rotor vibration detection system as described above includes a helicopter rotor, a reader, and a plurality of sensing tags. The sensing tags are all passive radio frequency tags, the sensing tags are arranged on the helicopter rotor, and the reader can collect the phase signals of the sensing tags, and then extract the vibration characteristics of the helicopter rotor through the phase signals of the sensing tags.

[0034] Since passive radio frequency tags are used to detect the vibration characteristic signals of the helicopter rotor, it has the advantages of passive wireless non - contact detection, and can avoid the limitation that traditional wired sensors cannot be installed on the helicopter rotor.

[0035] It should be noted that as an aircraft, any modification of a helicopter requires strict airworthiness review to prove that it will not pose a threat to flight safety. Therefore, in the present invention, the vibration of the helicopter rotor is detected by pasting tags, which is to place the helicopter rotor in a test environment, rather than in a real flight environment. Otherwise, due to the interference of the tags (the attached objects) on the air flow, the safety during flight may be affected. In addition, if the tags fall off, they may become foreign objects during flight, damaging other components or causing accidents. The purpose of detecting the vibration of the helicopter rotor is to evaluate the structural health of the helicopter rotor in order to optimize the design performance of the helicopter rotor.

[0036] Since the sensing tag is not a single-point structure, when the sensing tag rotates with the helicopter rotor, the movement of the sensing tag can be divided into two parts: on the one hand, the sensing tag makes a circular motion with the rotor; on the other hand, every time it rotates one week, the angle of the sensing tag itself will also rotate 360°. Therefore, when the sensing tag rotates with the helicopter rotor, the sensing tag can be decomposed into a circular motion and a rotation around its own geometric center.

[0037] Therefore, a calibration tag 3 is also arranged on the helicopter rotor. The calibration tag 3 is also a passive radio frequency tag. The geometric center of the calibration tag 3 coincides with the rotation center of the helicopter rotor, and the reader can collect the phase signal of the calibration tag 3. Based on the calibration tag 3, the sensing tag can be synchronously dynamically calibrated, so as to avoid the interference of the phase change caused by the rotation of the sensing tag around its own geometric center during the rotation of the sensing tag with the helicopter rotor.

[0038] As shown in the appendix Figure 1 During the rotation of the helicopter rotor, its vibration can be divided into flapping vibration and torsional vibration. Therefore, several of the sensing tags are divided into a flapping vibration sensing tag array 1 and a torsional vibration sensing tag array 2. As shown in the appendix Figure 2 As shown, each of the sensing tags in the flapping vibration sensing tag array 1 is arranged on the axis of the helicopter rotor, while each of the sensing tags in the torsional vibration sensing tag array 2 is respectively arranged on the two side edges of the helicopter rotor.

[0039] The arrangement directions of the sensing tag and the calibration tag 3 on the helicopter rotor are the same.

[0040] When the helicopter rotor rotates at high speed, a large centrifugal force will be generated, and the centrifugal force will be even greater at the end of the helicopter rotor. When using traditional adhesives to paste the sensing label at the end of the helicopter rotor, the sensing label is likely to fall off under the action of the strong centrifugal force, resulting in the inability to continue the vibration detection test. Therefore, the sensing label near the end of the helicopter rotor is set as an anti-centrifugal force label. The anti-centrifugal force label is pasted under the helicopter rotor, and a slightly convex airfoil profile is formed on the lower surface of the anti-centrifugal force label. When the airflow passes through the airfoil profile on the lower surface of the anti-centrifugal force label, an upward acting force is generated on the anti-centrifugal force label, enabling the anti-centrifugal force label to overcome the centrifugal force and stick tightly to the end of the helicopter rotor, so that the label at the end of the helicopter rotor is not easily detached.

[0041] The sensing label itself needs to be thin and light enough to reduce the interference of the sensing label itself on the airflow. Since the anti-centrifugal force label itself has a slightly convex structure, it has a greater interference on the airflow. Therefore, in actual applications, the sensing label in a flat and thin shape is still mainly used, and the anti-centrifugal force label is used with caution. However, if the rotation speed of the helicopter rotor is very high during the test, resulting in a large centrifugal force, and the traditional adhesive cannot support the sensing label to remain stable at the end of the helicopter rotor, then the anti-centrifugal force label is used instead, sacrificing the test accuracy in exchange for the continuation of the vibration detection test.

[0042] The present invention also provides a detection method for a helicopter rotor vibration detection system. The general idea is to arrange calibration labels 3, a flap vibration sensing label array 1, and a torsional vibration sensing label array 2 on the helicopter rotor. During the operation of the helicopter, the phase signals of each label are collected, and the phase errors caused by the rotation of the azimuth of each sensing label itself when rotating with the helicopter rotor are eliminated. After eliminating the errors, the compressed sensing technology is used to recover and reconstruct the phase signals, thereby increasing the sampling frequency of the label phase signals and avoiding phase unwrapping errors caused by insufficient sampling frequency. The unwrapped phase signals are filtered according to the rotation frequency information of the calibration label 3 to extract the flap vibration characteristics. Subsequently, based on the rotation frequency information and the flap vibration characteristics, the torsional vibration sensing label signals are filtered to extract the torsional vibration characteristics. Specifically, it includes the following steps:

[0043] Step S1: Layout of label array measurement points: Arrange the sensing label and calibration label 3 on the helicopter rotor;

[0044] Step S2: Acquisition of original phase signals: The helicopter rotor rotates, and the phase signals of all arranged labels are synchronously collected;

[0045] Step S3: Synchronous dynamic calibration: Combine the phase signals of the calibration label 3 to perform synchronous dynamic calibration on the phase signals of the sensing labels;

[0046] Step S4: Compressive sensing reconstruction of phase: Perform compressive sensing processing on the phase signal after synchronous dynamic calibration to reconstruct the phase signal;

[0047] Step S5: Phase unwrapping processing: Perform phase unwrapping processing on the phase signal after compressive sensing processing;

[0048] Step S6: Extraction of vibration characteristic frequencies: Extract the flapping vibration characteristic signal and torsional vibration characteristics of the helicopter rotor from the unwrapped phase signal.

[0049] In step S1, a calibration label 3 is arranged at the rotation center of the helicopter rotor, and the geometric center of the calibration label 3 coincides with the rotation center of the helicopter rotor. Each label in the flapping vibration sensing label array 1 should be pasted at the axis of the helicopter rotor, and the relative error caused by the rotor torsion should be avoided as much as possible, and the label array density should be set according to the required spatial resolution of detection. Each label in the torsional vibration sensing label array 2 should be pasted on both sides of the helicopter rotor, and the label array density should be set according to the measured spatial resolution.

[0050] In addition, to ensure the synchronization of the label array, the sensing label and the calibration label 3 should maintain the same pasting direction. Specifically, the long sides of all labels should be parallel to each other at the initial pasting position to ensure synchronous calibration between the labels in the array.

[0051] In step S2, it is necessary to collect the phase signal changes of all labels. Among them, the phase signal change of the sensing label is:

[0052]

[0053] where λ is the wavelength of the electromagnetic wave in the communication band; is the fixed phase offset introduced by hardware such as the reader and the reader antenna; is the phase offset introduced by the rotation of the sensing label: dAP is the change in the distance between the label and the reader antenna, and dAP satisfies the following formula:

[0054]

[0055] where r is the distance between the geometric center of the measured passive RF tag and the rotation center of the helicopter rotor; α is the angle turned by the passive RF tag; L is the distance between the geometric center of the measured passive RF tag and the reader antenna in the z-axis direction; X2 and Y2 are the coordinates of the reader antenna in the three-dimensional coordinate system respectively.

[0056] And the phase signal change of the calibration label 3 is:

[0057]

[0058] Wherein, n is the rotational speed of the helicopter rotor.

[0059] In step S3, since the sensing tag rotates with the helicopter rotor and the sensing tag also rotates on its own axis, the phase signal of the calibration tag 3 is subtracted from the phase signal of each sensing tag to synchronously dynamically calibrate the phase signal of the sensing tag, and then the subsequent signal processing and analysis are carried out.

[0060] In step S4, according to the communication mechanism of RFID, the phase signals collected by the reader satisfy the sparsity and incoherence conditions required by compressive sensing. Therefore, the process of compressive sensing processing for the phase signals of the sensing tags includes: selecting an appropriate transformation matrix, constructing an observation matrix, and performing optimization and solution by minimizing the norm, and finally recovering and reconstructing the phase signals.

[0061] The reader collects the original phase signals of the sensing tags at a sampling frequency lower than 100 reads / s. However, since the time stamp resolution of the phase signal acquisition is at the millisecond level, after reconstruction by the compressive sensing method, the sampling frequency of the phase signal can reach 1000 reads / s.

[0062] In step S5, the phase signals reconstructed by compressive sensing are stored separately for subsequent processing. It is necessary to perform phase unwrapping after reconstructing the signal by compressive sensing, otherwise phase unwrapping errors may occur. In the appendix Figure 6 The threshold of 01 is 0.5π, the threshold of 02 is 1.0π, and the threshold of 03 is 1.5π. In the appendix Figure 7 The threshold of 01 is 0.5π, the threshold of 02 is 1.0π, and the threshold of 03 is 1.5π. When the sampling frequency is 100 reads / s, as Figure 6 shown by 01 and 03, improper threshold setting will produce incorrect unwrapping results. When the sampling frequency reaches 1000 reads / s after compressive sensing, as shown in the appendix Figure 7 all kinds of threshold settings can achieve the expected effect.

[0063] Therefore, when performing phase unwrapping processing, first calculate the difference between every two adjacent phase points, and then set a threshold, such as 1.5π. If the phase difference exceeds this threshold, it is considered that a phase jump occurs. If a jump occurs between adjacent phase values, adjust the latter phase value to eliminate the jump. Specifically, if the latter phase value is less than the former phase value, add 2π to the latter phase value; conversely, if the latter phase value is greater than the former phase value, subtract 2π. After correction, traverse all data points again, calculate the phase difference between adjacent points and check whether there are still jumps. If there are jumps, continue to correct; if there are no jumps, the unwrapping process ends; the condition for the end of unwrapping is that all phase differences are within the threshold range. At this time, the program stops correcting and outputs the unwrapped phase data.

[0064] In step S6, the method for extracting the characteristic frequency can refer to Figure 8 as shown in the attached Figure 8 In which, 01 is the rotational motion feature, 02 is the flapping vibration feature, 03 is the torsional vibration feature. The specific steps for extracting the characteristic frequency include the following:

[0065] Step S6.1: Perform Fourier transform on the calibration label 3 to obtain the rotational frequency information of the helicopter rotor's rotational motion;

[0066] Step S6.2: For the flapping vibration sensing label, since it is arranged at the axis of the helicopter rotor, the influence of its torsional vibration can be ignored. Therefore, when performing band-stop filtering on the signal after phase unwrapping of the flapping vibration sensing label, only filter out the rotational frequency and its harmonic signals obtained in step S6.1 to extract a relatively pure flapping vibration characteristic signal of the helicopter rotor;

[0067] Step S6.3: Perform band-stop filtering on the signal after phase unwrapping of the torsional vibration sensing label, filter out the rotational frequency and its harmonic signals obtained in step S6.1, and the flapping vibration frequency signal obtained in step S6.2, so as to obtain the torsional vibration characteristic signal of the helicopter rotor.

[0068] The above is only the preferred embodiment of the present invention. It should be noted that: for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A helicopter rotor vibration detection system, characterized in that: It includes a helicopter rotor, a reader, and several sensing tags; all the sensing tags are passive radio frequency tags, the sensing tags are arranged on the helicopter rotor, the reader can collect the phase signals of the sensing tags, and then extract the vibration characteristics of the helicopter rotor through the phase signals of the sensing tags; A calibration tag (3) is also arranged on the helicopter rotor, the calibration tag (3) is also a passive radio frequency tag, the geometric center of the calibration tag (3) coincides with the rotation center of the helicopter rotor, and the reader can collect the phase signal of the calibration tag (3).

2. The helicopter rotor vibration detection system according to claim 1, wherein: Several of the sensing tags are divided into a flap vibration sensing tag array (1) and a torsion vibration sensing tag array (2). Each sensing tag in the flap vibration sensing tag array (1) is arranged on the axis of the helicopter rotor, and each sensing tag in the torsion vibration sensing tag array (2) is respectively arranged on both side edges of the helicopter rotor.

3. The helicopter rotor vibration detection system according to claim 2, characterized in that: The sensing tag close to the end of the helicopter rotor is an anti - centrifugal force tag. The anti - centrifugal force tag is pasted under the helicopter rotor, and a micro - convex airfoil profile is formed on the lower surface of the anti - centrifugal force tag; when the air flow passes through the airfoil profile on the lower surface of the anti - centrifugal force tag, an upward acting force is generated on the anti - centrifugal force tag, so that the anti - centrifugal force tag can overcome the centrifugal force and stick tightly to the end of the helicopter rotor.

4. The detection method of a helicopter rotor vibration detection system according to claim 2, characterized in that: It includes the following steps: Step S1: Arrange the sensing tags and the calibration tag (3) on the helicopter rotor; Step S2: The helicopter rotor rotates, and synchronously collect the phase signals of all the arranged tags; Step S3: Combine the phase signal of the calibration tag (3) to perform synchronous dynamic calibration on the phase signals of the sensing tags; Step S4: Perform compressive sensing processing on the synchronously dynamically calibrated phase signals to reconstruct the phase signals; Step S5: Perform phase unwrapping processing on the phase signals after compressive sensing processing; Step S6: Extract the flap vibration characteristic signal and the torsion vibration characteristics of the helicopter rotor from the unwrapped phase signals.

5. The detection method of a helicopter rotor vibration detection system according to claim 4, characterized in that: In step S1, arrange the calibration tag (3) at the rotation center of the helicopter rotor, and arrange the sensing tags on the axis and both sides of the helicopter rotor to respectively form a flap vibration sensing tag array (1) and a torsion vibration sensing tag array (2).

6. The detection method of a helicopter rotor vibration detection system according to claim 5, characterized in that: In step S2, the change of the phase signal of the sensing tag is: where λ is the wavelength of electromagnetic waves in the communication frequency band; is the fixed phase offset introduced by the hardware; is the phase offset introduced by the rotation of the tag: dAP is the change in the distance between the tag and the reader antenna, and dAP satisfies the following formula: where r is the distance between the geometric center of the measured passive radio frequency tag and the rotation center of the helicopter rotor; α is the angle turned by the passive radio frequency tag; L is the distance between the geometric center of the measured passive radio frequency tag and the reader antenna in the z - axis direction; X2 and Y2 are the coordinates of the reader antenna in the three - dimensional coordinate system respectively; The change of the phase signal of the calibration tag (3) is: where n is the rotational speed of the helicopter rotor.

7. The detection method of a helicopter rotor vibration detection system according to claim 6, characterized in that: In step S3, since the sensing tag will also rotate itself when rotating with the helicopter rotor, subtract the phase signal of the calibration tag (3) from the phase signal of each sensing tag to perform synchronous dynamic calibration on the phase signals of the sensing tags.

8. The detection method of a helicopter rotor vibration detection system according to claim 7, characterized in that: In step S4, the process of performing compressive sensing processing on the phase signals of the sensing tags includes: selecting an appropriate transformation matrix, constructing an observation matrix, performing optimization and solution by minimizing the norm, and finally restoring and reconstructing the phase signals.

9. The detection method of a helicopter rotor vibration detection system according to claim 8, characterized in that: In step S5, the phase signal after compressive sensing reconstruction is stored separately; then, the difference between every two adjacent phase points is calculated; A threshold is set. If the phase difference exceeds the threshold, it is considered that a phase jump occurs; if a jump appears between adjacent phase values, the jump is eliminated by adjusting the latter phase value; after correction, if there is still a jump, continue the correction; if there is no jump, the phase unwrapping process ends; the condition for the end of phase unwrapping is that all phase differences are within the threshold range.

10. The detection method of a helicopter rotor vibration detection system according to claim 9, characterized in that: Step S6 specifically includes the following steps: Step S6.1: Perform a Fourier transform on the calibration tag (3) to obtain the rotational frequency information of the helicopter rotor's rotational motion; Step S6.2: Perform a band-stop filtering process on the signal after phase unwrapping of the flapping vibration sensing tag to filter out the rotational frequency and its harmonic signals obtained in step S6.1, so as to extract the flapping vibration characteristic signal of the helicopter rotor; Step S6.3: Perform a band-stop filtering process on the signal after phase unwrapping of the torsional vibration sensing tag to filter out the rotational frequency and its harmonic signals obtained in step S6.1, as well as the flapping vibration frequency signal obtained in step S6.2, so as to obtain the torsional vibration characteristic signal of the helicopter rotor.

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