A method and device for testing the validity of helicopter blade load data

Abstract

The application provides a helicopter blade load data test validity judgment method and device, which selects normal blade load data and inspected flight blade load data under the same characteristic state; phase alignment is performed on the two groups of selected data, and load data in two rotating periods is selected from the two groups of data; abnormal value judgment is performed on the selected load data, abnormal value elimination and point supplementing are performed, and two groups of corrected blade load data are obtained; then, correlation calculation is performed on the two groups of corrected blade load data, and a correlation coefficient R is obtained; finally, the obtained correlation coefficient R is compared with a set threshold value, whether the inspected flight blade load data test is effective is judged, monitoring faults caused by test faults can be identified, fault ranges can be prompted, monitoring personnel can be assisted in judging problems, and flight safety can be ensured.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of helicopter flight load test, and particularly relates to a helicopter blade load data test validity judgment method and device. BACKGROUND

[0002] Helicopter flight load test is an important link in helicopter flight test, is the only means to verify the reliability of the blade structure of the helicopter and evaluate the service life, and new helicopter must pass the flight load test to fully verify the blade before finalization.

[0003] The helicopter blade load test system shoulders the task of testing and recording data, and must ensure the correctness of the measured data. At present, it is extremely difficult to judge whether the data is abnormal manually, and errors are prone to occur. SUMMARY

[0004] In order to solve the problem that manual judgment of whether the data is abnormal is extremely difficult and prone to errors in the prior art, the present application provides a helicopter blade load data test validity judgment method and device, which can be used for the characteristic validity of helicopter blade load actual measurement data, realize the evaluation and monitoring of the working stability of the test system, avoid invalid flight cycles caused by abnormal test data in advance, and improve the comprehensive efficiency of flight test work. The technical solution is as follows:

[0005] In the first aspect, a helicopter blade load data test validity judgment method is provided, and the method comprises:

[0006] Step 1: selecting normal blade load data under the same characteristic state and blade load data of the inspected flight cycle;

[0007] Step 2: phase alignment is performed on the two groups of selected data, and load data in 2 rotation periods is selected from each of the two groups of data;

[0008] Step 3: abnormal value judgment is performed on the selected load data, abnormal value elimination and point supplementing are performed, and two groups of corrected blade load data are obtained;

[0009] Step 4: correlation calculation is performed on the two groups of corrected blade load data, and a correlation coefficient R is obtained;

[0010] Step 5: the obtained correlation coefficient R is compared with a set threshold value, and whether the blade load data test of the inspected flight cycle is effective is judged.

[0011] The flight load of the helicopter blade has similar frequency components and time domain amplitudes under certain driving conditions, and there is no large change. Therefore, by comparing the blade load data correlation under normal conditions and target conditions, the characteristic effectiveness of the helicopter blade load measurement data can be analyzed, the stability of the test system can be evaluated and monitored, and invalid flight cycles caused by abnormal test data can be avoided in advance.

[0012] Optionally, in step 1, the characteristic state is the slow running state, that is, the total distance = 0 and the rotor speed Nr = the ground slow running driving state speed.

[0013] Optionally, in step 2, when the load data in 2 rotation periods is selected, the number of selected data points = 2*60*f / Nr, wherein f is the sampling rate, the true value of which is greater than Nr*200 / 60; Nr is the rotor speed; and 2 is the number of periods.

[0014] Optionally, in step 2, the selected starting point N is at the peak of the blade load time domain curve.

[0015] Optionally, in step 3, the abnormal value judgment process is:

[0016] The slope K of the adjacent points of the blade load data points of the inspected flight cycle is ∈(-2f, 2f), if the slope exceeds the range, the latter point of the two points is removed, and the slope is recalculated by selecting the subsequent point and its previous point, at this time the slope K of the adjacent two points is ∈(-4f, 4f), if the slope continues to exceed this range, the newly selected subsequent point is removed, and the slope is recalculated by selecting the next new subsequent point and its previous point, at this time the slope K of the adjacent two points is ∈(-6f, 6f), if the slope still does not meet the requirement, it is determined that the complete period data point is not available, the next period data point is selected, if it meets the requirement, it is calculated until all abnormal points are removed, and the correlation is calculated.

[0017] Optionally,

[0018] After removing the abnormal points of the blade load data of the inspected flight cycle, the data points corresponding to the positions of the normal blade load data should be removed to ensure that the number of data points of the two groups is consistent, and then the correlation is calculated, and the total number of removed points is not more than 1% of the total number of points.

[0019] Optionally, in step 5, the threshold is set to 0.9, if the correlation R>0.9, it is determined that the blade load data test of the inspected flight cycle is effective, if the correlation R≤0.9, it is determined that the blade load data test of the inspected flight cycle is invalid.

[0020] In a second aspect, a helicopter blade load data test effectiveness judgment method and device are provided, comprising:

[0021] The selection module is configured to select normal blade load data and inspected flight cycle blade load data under the same characteristic state.

[0022] a processing module, configured to perform phase alignment on the selected two groups of data, and select load data in two rotation periods in each of the two groups of data;

[0023] a judging module, configured to perform outlier judgment on the selected load data, perform outlier elimination and point filling operation, and obtain two groups of corrected blade load data;

[0024] a calculating module, configured to perform correlation calculation on the two groups of corrected blade load data, and obtain a correlation coefficient R;

[0025] a comparing module, configured to compare the obtained correlation coefficient R with a set threshold value, and judge whether the blade load data test of the inspected flight is valid.

[0026] In a third aspect, a helicopter blade load data test validity judgment method device is provided, including a processor and a memory, the processor is configured to execute instructions stored in the memory, and the processor realizes the helicopter blade load data test validity judgment method in any one of the first aspect by executing the instructions.

[0027] In a fourth aspect, a computer readable storage medium is provided, the computer readable storage medium stores instructions, when the instructions run on a processing component of a computer, the processing component executes the helicopter blade load data test validity judgment method in any one of the first aspect.

[0028] In a fifth aspect, a computer program product including instructions is provided, when the computer program product runs on a computer, the computer executes the helicopter blade load data test validity judgment method in any one of the first aspect.

[0029] The helicopter blade load data test validity judgment method provided by the application has at least the following beneficial effects:

[0030] The application first selects normal blade load data and inspected flight blade load data under the same characteristic state, performs phase alignment on the selected two groups of data, selects load data in two rotation periods in each of the two groups of data, performs outlier judgment on the selected load data, performs outlier elimination and point filling operation, obtains two groups of corrected blade load data, performs correlation calculation on the two groups of corrected blade load data, obtains a correlation coefficient R, compares the obtained correlation coefficient R with a set threshold value, judges whether the inspected flight blade load data test is valid, can identify monitoring failure caused by test failure, prompts the failure range, assists monitoring personnel in judging the problem, and guarantees flight safety. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1A helicopter blade load data test validity judgment method flow chart provided by the embodiment of the present application;

[0032] Figure 2 A normal data and test data curve diagram of the embodiment 1 of the present application;

[0033] Figure 3 A test data curve diagram of the embodiment 2 of the present application. DETAILED DESCRIPTION

[0034] The present application is further described in detail below through specific embodiments and drawings.

[0035] The present application can provide guidance for helicopter blade load data validity check, can be used for large quantities of data test validity check, and can exclude error and abnormal data caused by test system failure, thereby reducing the influence on subsequent load calculation.

[0036] Please refer to Figure 1 The present application provides a helicopter blade load data test validity judgment method, and the main steps are as follows:

[0037] Step 1: selecting normal blade load data and the blade load data of the checked flight under the same characteristic state.

[0038] The characteristic state requires the slow vehicle state, that is, the total distance = 0, and the rotor speed Nr = the ground slow start speed.

[0039] Step 2: phase alignment is performed on the selected two groups of data, and load data in 2 rotation periods is selected from the two groups of data respectively;

[0040] When the load data in 2 rotation periods is selected, the selected data point number = 2*60*f / Nr, wherein f is the sampling rate, the true value of which is usually greater than Nr*200 / 60; Nr is the rotor speed; and 2 is the period number.

[0041] The selected starting point N is at the peak of the blade load time domain curve, and the selected starting position is as shown in Figure 2

[0042] Step 3: abnormal value judgment is performed on the selected load data, abnormal value elimination and point supplement operations are performed, and the two groups of corrected blade load data are obtained;

[0043] In one implementation manner, the abnormal value judgment process is as follows:

[0044] ​The slope of the adjacent points of the inspected blade load data point is K∈(-2f, 2f). If the slope exceeds the range, the latter point of the two points is eliminated, and the subsequent point and its predecessor are selected to recalculate the slope. At this time, the slope of the two adjacent points is K∈(-4f, 4f). If the slope continues to exceed this range, the newly selected subsequent point is eliminated, and the next new subsequent point and its predecessor are selected to recalculate the slope. At this time, the slope of the two adjacent points is K∈(-6f, 6f). If the slope still does not meet the requirements, it is determined that the data points of this complete cycle are unavailable (if there are not enough data points to select for three consecutive times, this determination will not be made), and selection will start from the data points of the next cycle. If it meets the requirements, calculation will be continued until all abnormal points are eliminated and the correlation is calculated.

[0045] After eliminating abnormal points in the blade load data of the inspected flight, the data points at the corresponding positions of the normal blade load data should be eliminated to ensure that the number of data points in the two groups is consistent, and then the correlation is calculated. In order to avoid data distortion, the total number of eliminated points should not exceed 1% of the total number of points.

[0046] Step 4: Calculate the correlation between the two sets of corrected blade load data to obtain the correlation coefficient R. The calculation formula is:

[0047]

[0048] Step 5: Compare the calculated correlation coefficient R with the set threshold to determine whether the blade load data test of the inspected flight is valid.

[0049] For example, when the threshold is set to 0.9 and the correlation N is greater than 0.9, the data is normal. When the correlation is between 0.8 and 0.9, manual judgment is required to check whether the abnormal points are removed and repaired, resulting in similarity distortion. If so, a clean test sample is selected and recalculated. If not, the test channel is faulty. When N is less than 0.8, the test channel is faulty and needs to be repaired.

[0050] In one embodiment, if Figure 2 The figure below shows a comparison of two periodic signals of a load data. The dotted line represents normal data, and the solid line represents the current test data. After correlation calculation, the correlation between the two signals is 0.9769. Therefore, the data of this test channel is considered normal.

[0051] In one embodiment, if Figure 3 As shown, this is a load signal with a sampling rate of 1024. The slopes from point 1 to point 2, point 3, and point 4 are 7652760, 5402594, and 4119642, respectively. These are much larger than those determined in step 3 of the method. Therefore, this test data cannot be determined.

[0052] An embodiment of the present invention further provides a method and apparatus for testing the effectiveness of helicopter blade load data, comprising:

[0053] The selecting module is configured to select normal blade load data and inspected blade load data under the same feature state;

[0054] The processing module is configured to perform phase alignment on the two selected groups of data and select load data in 2 rotation periods in each of the two groups of data;

[0055] The judging module is configured to perform outlier judgment on the selected load data, perform outlier elimination and point supplementing, and obtain two groups of corrected blade load data;

[0056] The calculating module is configured to perform correlation calculation on the two groups of corrected blade load data and obtain a correlation coefficient R;

[0057] The comparing module is configured to compare the obtained correlation coefficient R with a set threshold value and judge whether the inspected blade load data test is valid.

[0058] The specific execution process of each module in the present application can refer to the specific process of the related steps of the above method, and will not be described here.

[0059] An embodiment of the present application further provides a helicopter blade load data test validity judgment method device, which comprises a processor and a memory, the processor is configured to execute instructions stored in the memory, and the processor realizes the helicopter blade load data test validity judgment method provided by the present application by executing the instructions.

[0060] An embodiment of the present application further provides a computer readable storage medium, which stores instructions, and when the instructions run on a processing component of a computer, the processing component executes the helicopter blade load data test validity judgment method provided by the present application.

[0061] An embodiment of the present application further provides a computer program product comprising instructions, and when the computer program product runs on a computer, the computer executes the helicopter blade load data test validity judgment method provided by the present application.

[0062] The above only expresses the embodiments of the present application, the description is more specific and detailed, but it cannot be understood as the limitation of the patent scope. It should be noted that for ordinary skilled persons in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. In addition, the parts not described in the present application are all conventional technologies.

Claims

1. A method of testing the validity of helicopter blade load data, characterized in that, The method comprises: Step 1: selecting normal blade load data and the blade load data of the inspected flight under the same characteristic state; Step 2: performing phase alignment on the two groups of selected data, and selecting load data in 2 rotation periods in each of the two groups of data; Step 3: performing abnormal value judgment on the selected load data, performing abnormal value elimination and point supplementing, and obtaining two groups of corrected blade load data; Step 4: performing correlation calculation on the two groups of corrected blade load data, and obtaining a correlation coefficient R; Step 5: comparing the obtained correlation coefficient R with a set threshold value, and judging whether the blade load data test of the inspected flight is effective; In step 3, the abnormal value judgment process is as follows: the slope K of the adjacent points of the blade load data point of the inspected flight is in the range of (-2f, 2f), if the slope exceeds the range, the latter point of the two points is eliminated, and the slope is recalculated by selecting a subsequent point and a previous point thereof, at this time, the slope K of the adjacent two points is in the range of (-4f, 4f), if the slope continues to exceed the range, the newly selected subsequent point is eliminated, and the slope is recalculated by selecting a next new subsequent point and a previous point thereof, at this time, the slope K of the adjacent two points is in the range of (-6f, 6f), if the slope still does not meet the requirement, it is determined that the complete period data point is unusable, the selection is started from the next period data point, if the requirement is met, the calculation is continued, until the correlation is calculated after all abnormal points are eliminated; f is a sampling rate. In step 1, the characteristic state is the slow running state, that is, the total distance = 0, and the rotor speed Nr = the ground slow running state speed.

2. The method of claim 1, wherein, In step 2, when the load data in 2 rotation periods is selected, the selected data point number = 2*60*f / Nr, wherein f is a sampling rate, the true value of which is greater than Nr*200 / 60; Nr is a rotor speed; 2 is a period number.

3. The method of claim 1, wherein, In step 2, the selected starting point N is at the peak of the blade load time domain curve.

4. The method of claim 1, wherein, 5. The method of claim 1, wherein, After the abnormal points of the blade load data of the inspected flight are eliminated, the data points at the corresponding positions of the normal blade load data should be eliminated, the number of data points of the two groups is ensured to be consistent, the correlation is calculated again, and the total number of eliminated points is not greater than 1% of the total number of points. In step 5, the set threshold value is 0.9, if the correlation R > 0.9, it is determined that the blade load data test of the inspected flight is effective, if the correlation R ≤ 0.9, it is determined that the blade load data test of the inspected flight is ineffective.

6. The method of claim 1, wherein, Comprise:

7. A method and device for checking the validity of helicopter blade load data testing, characterized in that: The selecting module is used for selecting normal blade load data and the blade load data of the inspected flight under the same characteristic state; The processing module is used for performing phase alignment on the two groups of selected data, and selecting load data in 2 rotation periods in each of the two groups of data; The judgment module is used for performing abnormal value judgment on the selected load data, performing abnormal value elimination and point supplementing, and obtaining two groups of corrected blade load data; The calculation module is used for performing correlation calculation on the two groups of corrected blade load data, and obtaining a correlation coefficient R; The comparison module is used for comparing the obtained correlation coefficient R with a set threshold value, and judging whether the blade load data test of the inspected flight is effective. ​ 8. A method of determining the validity of test helicopter blade load data, comprising: The helicopter blade load data test validity judging method according to any one of claims 1 to 6 is implemented by a processor configured to execute instructions stored in a memory.

9. A computer-readable storage medium, characterized in that, The computer readable storage medium stores instructions, and when the instructions run on a processing component of a computer, the processing component executes the helicopter blade load data test validity judging method according to any one of claims 1 to 6.

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