A Comparative Evaluation Method for Wind Tunnel Balance Formulas Based on Pose Transformation Correction

Abstract

The present invention proposes a method for comparative evaluation of wind tunnel balance formulas based on pose conversion correction, belonging to the technical field of aircraft aerodynamic performance evaluation. Compile a six-dimensional force calibration and inspection load table; apply a six-dimensional force calibration load to the wind tunnel balance, collect the response output voltage of each component Wheatstone bridge, and fit to generate a wind tunnel balance formula; solve the applied six-dimensional force load; evaluate the prediction ability of the wind tunnel balance formula obtained in the current calibration in the wind tunnel test in the form of standard deviation; calculate the relative deviation of the six-component main term coefficient; calculate the pose change value of the wind tunnel balance relative to the balance calibration device when calibrating the wind tunnel balance twice; correct the inspection load table for inspecting the wind tunnel balance in the previous calibration; solve the six-dimensional force load applied to the wind tunnel balance in the previous inspection; evaluate the prediction ability of the wind tunnel balance formula obtained in the current calibration in the wind tunnel test in the form of standard deviation; solve the problem of systematic error or random error during the balance calibration process when evaluating the inspection points.

Description

Technical Field

[0001] The present application relates to a method for comparing and evaluating wind tunnel balance formulas, in particular to a method for comparing and evaluating wind tunnel balance formulas based on pose transformation correction, an electronic device, and a storage medium, belonging to the technical field of comparing and evaluating wind tunnel balance formulas. Background Technique

[0002] Aerodynamic performance is one of the key factors in evaluating the success or failure of aircraft model development. Precise aerodynamic design and accurate aerodynamic prediction are the primary conditions to ensure that the aircraft has excellent aerodynamic performance. Currently, wind tunnel tests are the main means for accurate aerodynamic prediction and are directly involved in the aerodynamic design process of aircraft. In wind tunnel tests, a wind tunnel balance directly senses the aerodynamic force load acting on the scaled model of the aircraft, and each component Wheatstone bridge responds by outputting a voltage. Then, the aerodynamic force load acting on the scaled model of the aircraft is obtained by applying the wind tunnel balance formula for calculation.

[0003] The calibration of the wind tunnel balance formula is the reverse process of the wind tunnel test, that is, an accurate known load is applied to the wind tunnel balance on the balance calibration device, and each component Wheatstone bridge responds by outputting a voltage, and then it is obtained through a data processing method. The specific calibration process of the wind tunnel balance formula: First, according to the design load of the wind tunnel balance, a six-dimensional force calibration load table is compiled; Second, on the balance calibration device, an accurate six-dimensional force calibration load is applied to the wind tunnel balance according to the known coordinate system and the compiled calibration load table, and at the same time, the response output voltage of each component Wheatstone bridge is collected; Finally, when all the load groups in the load table are loaded, a calibration data processing method is applied to fit and generate the wind tunnel balance formula.

[0004] After obtaining the wind tunnel balance formula, it is necessary to evaluate its prediction ability in wind tunnel tests to ensure that the wind tunnel balance formula meets the expected accuracy requirements. The evaluation method is carried out by means of checkpoints. The specific process: First, according to the estimated measurement load of the wind tunnel test, a six-dimensional force check load table is compiled; Second, on the balance calibration device, an accurate six-dimensional force check load is applied to the wind tunnel balance according to the known coordinate system and the compiled check load table, and at the same time, the response output voltage of each component Wheatstone bridge is collected; Then, the wind tunnel balance formula is applied, combined with the response output voltage of each component Wheatstone bridge, to calculate and obtain the applied six-dimensional force load; Finally, by comparing each group of accurately applied six-dimensional force check loads with the calculated applied six-dimensional force loads, the residuals of each group of six-dimensional force loads can be obtained and evaluated in the form of standard deviation. Only when it is better than the qualified index required by GJB2244A-2011 "Specification for Wind Tunnel Strain Balance" can it be put into application in wind tunnel tests.

[0005] However, the validity period of the wind tunnel balance formula is generally stipulated as two years. Therefore, during the whole life cycle of the wind tunnel balance, it is necessary to calibrate it multiple times on one balance calibration device or on different balance calibration devices, that is, there are multiple sets of wind tunnel balance formulas. The above-described method for evaluating the prediction ability of the wind tunnel balance formula in wind tunnel tests only targets a specific wind tunnel balance formula obtained by calibration on a single-use balance calibration device. When systematic errors or random errors occur during the balance calibration process (such as deviations in the bridge supply voltage of the data acquisition system), this method for evaluating the prediction ability cannot detect and eliminate problems in a timely manner, which will inevitably lead to invalid wind tunnel test data and cause serious consequences. Summary of the Invention

[0006] A brief overview of the present invention is given below to provide a basic understanding of certain aspects of the present invention. It should be understood that this overview is not an exhaustive overview of the present invention. It is not intended to identify the key or important parts of the present invention, nor is it intended to limit the scope of the present invention. Its purpose is only to present certain concepts in a simplified form as a prelude to the more detailed description that follows.

[0007] In view of this, to solve the technical problem in the prior art that when using the method of taking inspection points for evaluation, when systematic errors or random errors occur during the balance calibration process, this method for evaluating the prediction ability cannot detect and eliminate problems in a timely manner, which will inevitably lead to invalid wind tunnel test data and cause serious consequences. The present invention provides a method, an electronic device, and a storage medium for comparing and evaluating wind tunnel balance formulas based on pose transformation correction.

[0008] Solution 1: A method for comparing and evaluating wind tunnel balance formulas based on pose transformation correction, comprising the following steps:

[0009] S1. Compile a six-dimensional force calibration load table according to the design load of the wind tunnel balance;

[0010] S2. Apply precise six-dimensional force calibration loads to the wind tunnel balance according to the known coordinate system of the balance calibration device and the six-dimensional force calibration load table, and simultaneously collect the response output voltages of the corresponding components of the Wheatstone bridge;

[0011] S3. Apply the global regression algorithm to fit and generate the wind tunnel balance formula;

[0012] S4. Compile a six-dimensional force inspection load table according to the estimated measurement load of the wind tunnel test;

[0013] S5. Apply precise six-dimensional force calibration loads to the wind tunnel balance according to the known coordinate system of the balance calibration device and the six-dimensional force inspection load table, and simultaneously collect the response output voltages of the corresponding components of the Wheatstone bridge;

[0014] S6. Based on the wind tunnel balance formula and the output voltages of the Wheatstone bridge responses of each component, iteratively solve to obtain the applied six-dimensional force load;

[0015] S7. Compare the six-dimensional force test load table with the applied six-dimensional force load to obtain the residuals of each group of six-dimensional force loads, calculate the standard deviation of each component of the wind tunnel balance, and evaluate the prediction ability of the wind tunnel balance formula obtained in the current calibration in the wind tunnel test in terms of the standard deviation;

[0016] S8. Extract the six-component main term coefficients in the wind tunnel balance formula and the wind tunnel balance formula obtained in the previous calibration of the wind tunnel balance, and calculate the relative deviation of the six-component main term coefficients;

[0017] S9. Extract the wind tunnel balance formula and the formula for the applied six-dimensional force load obtained by iterative solution. For the output voltages of the Wheatstone bridge responses of each component in the unit loading normal force, pitching moment, and lateral force parts of the calibration load table of the previous calibration of the wind tunnel balance, iteratively solve to obtain the corresponding six-dimensional force load; calculate the pose change value of the wind tunnel balance relative to the balance calibration device when calibrating the wind tunnel balance twice;

[0018] S10. According to the pose change value of the wind tunnel balance relative to the balance calibration device when calibrating the wind tunnel balance twice, correct the test load table for calibrating the wind tunnel balance in the previous calibration;

[0019] S11. Extract the wind tunnel balance formula and the formula for the applied six-dimensional force load obtained by iterative solution. For the output voltages of the Wheatstone bridge responses of each component in the test load table for loading the test load of the previous test of the wind tunnel balance, iteratively solve to obtain the six-dimensional force load applied to the wind tunnel balance in the previous test;

[0020] S12. Compare the corrected test load table for calibrating the wind tunnel balance in the previous calibration and the six-dimensional force load applied to the wind tunnel balance obtained by solution to obtain the residuals of each group of six-dimensional force loads, and evaluate the prediction ability of the wind tunnel balance formula obtained in the current calibration in the wind tunnel test in terms of the standard deviation.

[0021] Preferably, the wind tunnel balance formula is:

[0022]

[0023] In the formula, i, j, and k are the indices of each component of the wind tunnel balance; F i is the load for fitting the formula of the i-th component of the wind tunnel balance; a i is the main term coefficient of the i-th component; ΔU i is the output voltage of the Wheatstone bridge response of the i-th component; b i j is the first-order interference correction coefficient of the j-th component load on the i-th component; c i jkis the second-order square term interference coefficient and the cross-term interference correction coefficient of the j and k components with respect to the i component; P j and P k are the loads of the j and k components of the wind tunnel balance.

[0024] Preferably, the formula for the six-dimensional force load applied by iterative calculation is:

[0025] F i0 = a i *ΔU i

[0026]

[0027] where h is the number of iterative calculations, and the sequential values during the iterative process are 1, 2, 3, 4, 5, 6, 7 respectively, q = h - 1; F i0 is the load obtained by multiplying the main term coefficient of the i component by the output voltage of the Wheatstone bridge response; F ih is the load of the i component in the hth iterative calculation; P jq and P kq are the loads of the j and k components of the wind tunnel balance that have been calculated in the qth iteration;

[0028] Preferably, the formula for calculating the standard deviation of each component of the wind tunnel balance is:

[0029]

[0030] where m is the index of each group of loads in the test load table; n is the number of groups of loads in the test load table; σ i is the standard deviation of the i component of the wind tunnel balance; J im is the load value of the i component in the mth group in the test load table; JJ im is the load value of the i component in the mth group obtained by calculation; S i is the design load of the i component of the wind tunnel balance.

[0031] Preferably, the formula for calculating the relative deviation of the six-component main term coefficient is:

[0032]

[0033] where δ i is the relative deviation of the main term coefficient of the i component; a i1 is the main term coefficient of the i component of the wind tunnel balance formula obtained in this calibration; a i2 is the main term coefficient of the i component of the wind tunnel balance formula obtained in the previous calibration.

[0034] Preferably, the formula for the pose of the wind tunnel balance relative to the balance calibration device during two calibrations of the wind tunnel balance is:

[0035]

[0036] Wherein, Lx, Ly, and Lz are the three linear displacement change values of the wind tunnel balance relative to the balance calibration device along the X, Y, and Z axes of the right-handed coordinate system during two calibrations of the wind tunnel balance; α, β, and γ are the three angular displacement change values of the wind tunnel balance relative to the balance calibration device around the Z, Y, and X axes of the right-handed coordinate system during two calibrations of the wind tunnel balance; Y, M z y 、M x y 、X y and Z y are the normal force, pitching moment, rolling moment, axial force, and lateral force calculated when the unit loading normal force in the calibration load table; Mz and M x Mz are the pitching moment and rolling moment calculated when the unit loading pitching moment in the calibration load table; Z and M x z are the lateral force and rolling moment calculated when the unit loading lateral force in the calibration load table.

[0037] Preferably, the formula for correcting the inspection load table of the wind tunnel balance in the previous calibration inspection is:

[0038] Y m1 = Y m0 , M zm1 = M zm0 + Y m0 * Lx, M xm1 = M xm0 , X m1 = X m0 , Z m1 = Z m0 , M ym1 = M ym0 - Z m0 * Lx

[0039] Y m2 = Y m1 , M zm2 = M zm1 + X m1 * Ly, M xm2 = M xm1 + Z m1 * Ly, X m2 = X m1 , Z m2 = Z m1 , M ym2 = M ym1

[0040] Y m3 = Y m2 , Mzm3 = M zm2 , M xm3 = M xm2 - Y m2 * Lz, X m3 = X m2 , Z m3 = Z m2 , M ym3 = M ym2 - X m2 * Lz

[0041] Y m4 = Y m3 * cosα + X m3 * sinα, M zm4 = M zm3 , M xm4 = M xm3 * cosα + M ym3 * sinα, X m4 = X m3 * cosα - Y m3 * sinα, Z m4 = Z m3 , M ym4 = M ym3 * cosα - M xm3 * sinα

[0042] Y m5 = Y m4 , M zm5 = M zm4 * cosβ - M xm4 * sinβ, M xm5 = M xm4 * cosβ - M zm4 * sinβ, X m5 = X m4 * cosβ + Z m4 * sinβ, Z m5 = Z m4 * cosβ - X xm4 * sinβ, M ym5 = M ym4

[0043] Y m6 = Y m5 * cosγ + Z m5 * sinγ, M zm6 = M zm5 * cosγ - M ym5 * sinγ, M xm6 = M xm5 , X m6 = X m5 , Z m6= Z m5 * cosγ - Y m5 * sinγ, M ym6 = M ym5 * cosγ + M zm5 * sinγ

[0044] In the formula, Y m0 , M zm0 , M xm0 , X m0 , Z m0 and M ym0 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment of the m-th group in the test load table; Y m1 , M zm1 , M xm1 , X m1 , Z m1 and M ym1 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment of the m-th group in the test load table after load correction Lx; Y m2 , M zm2 , M xm2 , X m2 , Z m2 and M ym2 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment of the m-th group in the test load table after load corrections Lx and Ly; Y m3 , M zm3 , M xm3 , X m3 , Z m3 and M ym3 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment of the m-th group in the test load table after load corrections Lx, Ly, and Lz; Y m4 , M zm4 , M xm4 , X m4 , Z m4 and M ym4 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment of the m-th group in the test load table after load corrections Lx, Ly, Lz, and α; Y m5 , M zm5 , M xm5 , X m5 , Z m5 and M ym5 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment of the m-th group in the test load table after load corrections Lx, Ly, Lz, α, and β; Y m6 , M zm6 , M xm6 , Xm6 , Z m6 and M ym6 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment after correcting Lx, Ly, Lz, α, β, and γ for the m-th group of loads in the test load table;

[0045] Solution 2: An electronic device includes a memory and a processor. The memory stores a computer program. When the processor executes the computer program, the steps of a method for comparing and evaluating wind tunnel balance formulas based on pose transformation correction described in Solution 1 are implemented.

[0046] Solution 3: A computer-readable storage medium stores a computer program. When the computer program is executed by a processor, a method for comparing and evaluating wind tunnel balance formulas based on pose transformation correction described in Solution 1 is implemented.

[0047] The beneficial effects of the present invention are as follows:

[0048] (1) The present invention can promptly detect problems such as systematic errors or random errors occurring during the balance calibration process and eliminate them;

[0049] (2) The present invention can assist in evaluating and testing the uncertainty performance of a newly built balance calibration device;

[0050] (3) The present invention can be indirectly applied to on-line load correction at the wind tunnel test site, realizing the unification of pose transformation under two working conditions of balance calibration and wind tunnel test, thereby ensuring the accuracy of wind tunnel test data. Description of the Drawings

[0051] The drawings described herein are used to provide a further understanding of the present application, form a part of the present application, and the schematic embodiments and descriptions thereof are used to explain the present application and do not constitute an improper limitation of the present application. In the drawings:

[0052] Figure 1 is a schematic flow diagram of a method for comparing and evaluating wind tunnel balance formulas based on pose transformation correction;

[0053] Figure 2 is a diagram of the strain gauge pasting positions of a 47-diameter rod-type wind tunnel balance and a schematic diagram of the Cartesian coordinate system XOY;

[0054] Figure 3 is a top view of the strain gauge pasting positions of a 47-diameter rod-type wind tunnel balance;

[0055] Figure 4 is a sectional view A-A of the strain gauge pasting positions of a 47-diameter rod-type wind tunnel balance;

[0056] Figure 5It is the bridge circuit diagram of a 47-diameter rod-type wind tunnel balance, where a is Wheatstone bridge U1, b is Wheatstone bridge U2, c is Wheatstone bridge U3, d is Wheatstone bridge U4, e is Wheatstone bridge U5, and f is Wheatstone bridge U6. Specific implementation mode

[0057] In order to make the technical solutions and advantages in the embodiments of the present application clearer and more understandable, the following further details the exemplary embodiments of the present application with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than an exhaustive list of all embodiments. It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0058] Example 1. Refer to Figures 1-5 To illustrate this implementation mode, a method for comparative evaluation of wind tunnel balance formulas based on pose conversion correction includes the following steps:

[0059] S1. Compile a six-dimensional force calibration load table according to the design load of the wind tunnel balance;

[0060] S2. Apply accurate six-dimensional force calibration loads to the wind tunnel balance according to the known coordinate system of the balance calibration device and the six-dimensional force calibration load table, and simultaneously collect the response output voltages of the corresponding Wheatstone bridge components;

[0061] S3. Apply the global regression algorithm to fit and generate the wind tunnel balance formula;

[0062] The wind tunnel balance formula is:

[0063]

[0064] In the formula, i, j, and k are the indices of the components of the wind tunnel balance; F i is the load for which the formula of the i-th component of the wind tunnel balance is to be fitted and generated; a i is the main term coefficient of the i-th component; ΔU i is the response output voltage of the Wheatstone bridge of the i-th component; b i j is the first-order interference correction coefficient of the load of the j-th component on the i-th component; c i jk is the second-order square term interference coefficient and cross-term interference correction coefficient of the j-th and k-th components on the i-th component; P j and P k are the loads of the j-th and k-th components of the wind tunnel balance.

[0065] S4. Compile a six-dimensional force test load table according to the estimated measurement load of the wind tunnel test;

[0066] S5. Apply precise six - dimensional force calibration loads to the wind tunnel balance according to the known coordinate system of the balance calibration device and the six - dimensional force test load table, and simultaneously collect the response output voltages of the corresponding Wheatstone bridge components;

[0067] S6. According to the wind tunnel balance formula and the response output voltages of the Wheatstone bridge components, iteratively solve to obtain the applied six - dimensional force loads;

[0068] The formula for iteratively solving the applied six - dimensional force loads is:

[0069] F i0 =a i *ΔU i

[0070]

[0071] In the formula, h is the number of iterative calculations, and the sequential values during the iteration are 1, 2, 3, 4, 5, 6, 7 respectively, q = h - 1; F i0 is the load obtained by multiplying the main - term coefficient of the i - th component by the response output voltage of the Wheatstone bridge; F ih is the load of the i - th component in the h - th iterative calculation; P jq and P kq are the loads of the j - th and k - th components of the wind tunnel balance that have been calculated in the q - th iteration;

[0072] S7. Compare the six - dimensional force test load table with the applied six - dimensional force loads to obtain the residuals of each group of six - dimensional force loads, calculate the standard deviation of each component of the wind tunnel balance, and evaluate the prediction ability of the wind tunnel balance formula obtained in the current calibration in the wind tunnel test in the way of standard deviation;

[0073] The formula for calculating the standard deviation of each component of the wind tunnel balance is:

[0074]

[0075] In the formula, m is the index of each group of loads in the test load table; n is the number of groups of loads in the test load table; σ i is the standard deviation of the i - th component of the wind tunnel balance; J im is the value of the i - th component of the m - th group of loads in the test load table; JJ im is the value of the i - th component of the m - th group of loads obtained by solution; S i is the design load of the i - th component of the wind tunnel balance;

[0076] S8. Extract the six - component main - term coefficients in the wind tunnel balance formula and the wind tunnel balance formula obtained from the previous calibration of the wind tunnel balance, and calculate the relative deviation of the six - component main - term coefficients;

[0077] The formula for calculating the relative deviation of the six - component main - term coefficients is:

[0078]

[0079] wherein, δ i is the relative deviation of the main term coefficient of the i-th component; a i1 is the main term coefficient of the i-th component of the wind tunnel balance formula obtained from this calibration; a i2 is the main term coefficient of the i-th component of the wind tunnel balance formula obtained from the previous calibration;

[0080] S9. Extract the wind tunnel balance formula and the six-dimensional force load formula obtained by iterative solution. For the output voltage of the Wheatstone bridge response of each component in the normal force, pitch moment, and lateral force parts of the unit loading in the wind tunnel balance calibration load table for the previous calibration, iteratively solve the corresponding six-dimensional force load; calculate the pose change value of the wind tunnel balance relative to the balance calibration device when calibrating the wind tunnel balance twice;

[0081] The pose formula of the wind tunnel balance relative to the balance calibration device when calibrating the wind tunnel balance twice is:

[0082]

[0083] wherein, Lx, Ly, and Lz are the three linear displacement change values of the wind tunnel balance relative to the balance calibration device along the X, Y, and Z axes of the right-handed coordinate system when calibrating the wind tunnel balance twice; α, β, and γ are the three angular displacement change values of the wind tunnel balance relative to the balance calibration device around the Z, Y, and X axes of the right-handed coordinate system when calibrating the wind tunnel balance twice; Y, M z y , M x y , X y and Z y are the normal force, pitch moment, roll moment, axial force, and lateral force calculated when loading the normal force per unit in the calibration load table; Mz and M x Mz are the pitch moment and roll moment calculated when loading the pitch moment per unit in the calibration load table; Z and M x z are the lateral force and roll moment calculated when loading the lateral force per unit in the calibration load table;

[0084] S10. According to the pose change value of the wind tunnel balance relative to the balance calibration device when calibrating the wind tunnel balance twice, correct the inspection load table for inspecting the wind tunnel balance in the previous calibration;

[0085] The formula for correcting the inspection load table for inspecting the wind tunnel balance in the previous calibration is:

[0086] Y m1 = Y m0 , M zm1 = M zm0+Y m0 *Lx, M xm1 = M xm0 , X m1 = X m0 , Z m1 = Z m0 , M ym1 = M ym0 -Z m0 *Lx

[0087] Y m2 = Y m1 , M zm2 = M zm1 +X m1 *Ly, M xm2 = M xm1 +Z m1 *Ly, X m2 = X m1 , Z m2 = Z m1 , M ym2 = M ym1

[0088] Y m3 = Y m2 , M zm3 = M zm2 , M xm3 = M xm2 -Y m2 *Lz, X m3 = X m2 , Z m3 = Z m2 , M ym3 = M ym2 -X m2 *Lz

[0089] Y m4 = Y m3 *cosα + X m3 *sinα, M zm4 = M zm3 , M xm4 = M xm3 *cosα + M ym3 *sinα, X m4 = X m3 *cosα - Y m3 *sinα, Z m4 = Z m3 , M ym4 = M ym3 *cosα - M xm3 *sinα

[0090] Y m5 = Y m4 , Mzm5 = M zm4 * cosβ - M xm4 * sinβ, M xm5 = M xm4 * cosβ - M zm4 * sinβ, X m5 = X m4 * cosβ + Z m4 * sinβ, Z m5 = Z m4 * cosβ - X xm4 * sinβ, M ym5 = M ym4

[0091] Y m6 = Y m5 * cosγ + Z m5 * sinγ, M zm6 = M zm5 * cosγ - M ym5 * sinγ, M xm6 = M xm5 , X m6 = X m5 , Z m6 = Z m5 * cosγ - Y m5 * sinγ, M ym6 = M ym5 * cosγ + M zm5 * sinγ

[0092] Wherein, Y m0 , M zm0 , M xm0 , X m0 , Z m0 and M ym0 are the normal force, pitching moment, rolling moment, axial force, lateral force and yaw moment of the m-th group in the test load table; Y m1 , M zm1 , M xm1 , X m1 , Z m1 and M ym1 are the normal force, pitching moment, rolling moment, axial force, lateral force and yaw moment of the m-th group in the test load table after load correction Lx; Y m2 , M zm2 , M xm2 , X m2 , Z m2 and M ym2 are the normal force, pitching moment, rolling moment, axial force, lateral force and yaw moment of the m-th group in the test load table after load corrections Lx and Ly; Y m3 , Mzm3 , M xm3 , X m3 , Z m3 and M ym3 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment after correcting the Lx, Ly, and Lz of the m-th group of loads in the test load table; Y m4 , M zm4 , M xm4 , X m4 , Z m4 and M ym4 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment after correcting the Lx, Ly, Lz, and α of the m-th group of loads in the test load table; Y m5 , M zm5 , M xm5 , X m5 , Z m5 and M ym5 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment after correcting the Lx, Ly, Lz, α, and β of the m-th group of loads in the test load table; Y m6 , M zm6 , M xm6 , X m6 , Z m6 and M ym6 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment after correcting the Lx, Ly, Lz, α, β, and γ of the m-th group of loads in the test load table;

[0093] S11. Extract the wind tunnel balance formula and iteratively solve to obtain the applied six-dimensional force load formula. For the output voltage of the Wheatstone bridge response of each component in the test load table for the last inspection of the wind tunnel balance loading, iteratively solve to obtain the six-dimensional force load applied to the wind tunnel balance in the last inspection;

[0094] S12. Compare the corrected test load table for calibrating the wind tunnel balance last time with the solved six-dimensional force load applied to the wind tunnel balance in the last inspection to obtain the residuals of each group of six-dimensional force loads, and evaluate the prediction ability of the wind tunnel balance formula obtained in the current calibration in the wind tunnel test in the form of standard deviation.

[0095] This embodiment takes the 47-diameter rod-type wind tunnel balance as Figures 2-5 shown as an example to evaluate the prediction ability of the wind tunnel balance formula obtained by calibration in the wind tunnel test.

[0096] The balance is used to measure six components: the normal force Y, the pitching moment Mz, the rolling moment Mx, the axial force X, the lateral force Z, and the yaw moment My. 24 strain gauges are pasted on the balance body. Strain gauges 1, 2, 5, and 6 form a Wheatstone bridge U1 to correspondingly measure the normal force Y; strain gauges 3, 4, 7, and 8 form a Wheatstone bridge U2 to correspondingly measure the pitching moment Mz; strain gauges 9 to 12 form a Wheatstone bridge U3 to correspondingly measure the rolling moment Mx; strain gauges 13 to 16 form a Wheatstone bridge U4 to correspondingly measure the axial force X; strain gauges 17, 18, 21, and 22 form a Wheatstone bridge U5 to correspondingly measure the lateral force Z; strain gauges 19, 20, 23, and 24 form a Wheatstone bridge U6 to correspondingly measure the yaw moment My.

[0097] Step 1: According to the design load of the 47-diameter rod-type wind tunnel balance (normal force 1200 kgf, pitching moment 60 kgf·m, rolling moment 60 kgf·m, axial force 100 kgf, lateral force 200 kgf, yaw moment 20 kgf·m), compile a calibration load table.

[0098] Step 2: Apply precise six-dimensional force calibration loads to the wind tunnel balance on the balance calibration device according to the coordinate system in Figure 2 and the calibration load table compiled in Step 1, and simultaneously collect the response output voltages of the corresponding component Wheatstone bridges.

[0099]

[0100]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106]

[0107]

[0108]

[0109] Step 3: Apply the global regression algorithm based on the least squares principle and the data from Step 1 and Step 2 to fit and generate the formula 2 for this wind tunnel balance.

[0110]

[0111]

[0112] Step 4: Compile a six - dimensional force inspection load table according to the estimated measurement load from the wind tunnel test;

[0113] Step 5: Apply an accurate six - dimensional force calibration load to the wind tunnel balance on the balance calibration device according to the known coordinate system and the inspection load table compiled in Step 4, and simultaneously collect the response output voltages of the corresponding Wheatstone bridge components;

[0114]

[0115]

[0116] Step 6: Apply the wind tunnel balance formula generated by fitting in Step 3, combine it with the response output voltages of the Wheatstone bridge components collected during the loading in Step 5, and iteratively solve to obtain the applied six - dimensional force load;

[0117]

[0118]

[0119] Step 7: Compare the six - dimensional force inspection load table compiled in Step 4 with the applied six - dimensional force load obtained by solving in Step 6, obtain the residuals of each group of six - dimensional force loads, and evaluate the prediction ability of the wind tunnel balance formula obtained from this calibration in the wind tunnel test in the form of standard deviation, σ Y 、σ Mz 、σ Mx 、σ X 、σ Z and σ My are 0.06%, 0.1%, 0.13%, 0.27%, 0.07% and 0.08% respectively, meeting the qualified index requirements specified in GJB2244A - 2011 "Specification for Wind Tunnel Strain Balance", and partially meeting the advanced index requirements;

[0120] Step 8: Extract the six - component main - term coefficients in the wind tunnel balance formula generated by fitting in Step 3 and the wind tunnel balance formula obtained from calibrating this wind tunnel balance on another balance calibration device last time, calculate and comparatively analyze the relative deviations of the six - component main - term coefficients;

[0121]

[0122] Step 9: Apply the wind tunnel balance formula generated by fitting in step 3 and the iterative solution of the applied six-dimensional force load formula in step 6, and iteratively solve the corresponding six-dimensional force load for the Wheatstone bridge response output voltage of each component of the unit loading normal force, pitch moment and lateral force in the calibration load table of the wind tunnel balance last calibration; on this basis, solve and obtain the posture change value of the wind tunnel balance relative to the balance calibration device when the wind tunnel balance was calibrated twice, Lx, Ly and Lz are 0.96mm, -0.52mm and -0.07mm respectively, α, β and γ are -0.02°, -0.12° and 0.02° respectively;

[0123]

[0124]

[0125]

[0126]

[0127] Step 10: Apply the posture change value of the wind tunnel balance relative to the balance calibration device when the wind tunnel balance is calibrated twice obtained by the solution in step 9, and correct the test load table of the wind tunnel balance in the last calibration test;

[0128]

[0129]

[0130] Step 11: Apply the wind tunnel balance formula generated by fitting in step 3 and the iterative solution of the applied six-dimensional force load formula in step 6, and iteratively solve the six-dimensional force load applied to the wind tunnel balance in the last inspection according to the response output voltage of each component of the Wheatstone bridge of the load table of the last inspection of the wind tunnel balance;

[0131]

[0132]

[0133] Step 12: Compare the test load table of the last wind tunnel balance test obtained in step 10 with the six-dimensional force load applied to the wind tunnel balance in the last test obtained by solving step 11, and obtain the residuals of each group of six-dimensional force loads. Apply the formula for calculating the standard deviation of each component of the wind tunnel balance in step 7 to evaluate the predictive ability of the wind tunnel balance formula obtained in this calibration in the wind tunnel test in the form of standard deviation, σ Y , σ Mz , σ Mx , σ X , σ Z and σ MyThey are 0.03%, 0.12%, 0.10%, 0.32%, 0.24% and 0.34% respectively, meeting the qualified index requirements specified in GJB2244A-2011 "Wind Tunnel Strain Balance Specification", and some reaching the advanced index requirements.

[0134] Embodiment 2. The computer device of the present invention may be a device including a processor and a memory, such as a single-chip microcomputer including a central processing unit. And, when the processor is used to execute the computer program stored in the memory, the steps of the above-mentioned method for comparing and evaluating the wind tunnel balance formula based on pose transformation correction are realized.

[0135] The so-called processor may be a central processing unit (CPU), or may also be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0136] The memory may mainly include a program storage area and a data storage area. Among them, the program storage area may store an operating system, application programs required for at least one function (such as a sound playback function, an image playback function, etc.); the data storage area may store data created according to the use of the mobile phone (such as audio data, phone book, etc.). In addition, the memory may include high-speed random access memory, and may also include non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, at least one magnetic disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0137] Embodiment 3. Embodiment of the computer-readable storage medium

[0138] The computer-readable storage medium of the present invention may be any form of storage medium readable by the processor of the computer device, including but not limited to non-volatile memory, volatile memory, ferroelectric memory, etc. A computer program is stored on the computer-readable storage medium. When the processor of the computer device reads and executes the computer program stored in the memory, the steps of the above-mentioned method for comparing and evaluating the wind tunnel balance formula based on pose transformation correction can be realized.

[0139] The computer program includes computer program code, which may be in the form of source code, object code, executable files or some intermediate forms, etc. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately increased or decreased according to the requirements of legislation and patent practice within the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0140] Although the present invention has been described based on a limited number of embodiments, those skilled in the art in this technical field will understand that other embodiments can be conceived within the scope of the present invention thus described. In addition, it should be noted that the language used in this specification is mainly selected for readability and teaching purposes, rather than for the purpose of explaining or limiting the subject matter of the present invention. Therefore, many modifications and variations are obvious to those of ordinary skill in this technical field without departing from the scope and spirit of the appended claims. For the scope of the present invention, the disclosure made of the present invention is illustrative rather than restrictive, and the scope of the present invention is defined by the appended claims.

Claims

1. A method for comparative evaluation of wind tunnel balance formulas based on pose transformation correction, characterized in that, It includes the following steps: S1. Compile a six - dimensional force calibration load table according to the design load of the wind tunnel balance; S2. Apply precise six - dimensional force calibration loads to the wind tunnel balance according to the known coordinate system of the balance calibration device and the six - dimensional force calibration load table, and simultaneously collect the response output voltages of the corresponding component Wheatstone bridges; S3. Apply the global regression algorithm to fit and generate the wind tunnel balance formula; S4. Compile a six - dimensional force test load table according to the estimated measurement load of the wind tunnel test; S5. Apply precise six - dimensional force calibration loads to the wind tunnel balance according to the known coordinate system of the balance calibration device and the six - dimensional force test load table, and simultaneously collect the response output voltages of the corresponding component Wheatstone bridges; S6. Iteratively solve to obtain the applied six - dimensional force loads according to the wind tunnel balance formula and the response output voltages of the corresponding component Wheatstone bridges; S7. Compare the six - dimensional force test load table with the applied six - dimensional force loads to obtain the residuals of each group of six - dimensional force loads, calculate the standard deviation of each component of the wind tunnel balance, and evaluate the prediction ability of the wind tunnel balance formula obtained from the current calibration in the wind tunnel test in the form of standard deviation; S8. Extract the six - component main - term coefficients in the wind tunnel balance formula and the wind tunnel balance formula obtained from the previous calibration of the wind tunnel balance, and calculate the relative deviation of the six - component main - term coefficients; S9. Extract the wind tunnel balance formula and the formula for the applied six - dimensional force loads obtained by iterative solution. For the response output voltages of the corresponding component Wheatstone bridges in the unit - loading normal force, pitching moment, and lateral force parts of the calibration load table of the previous calibration of the wind tunnel balance, iteratively solve to obtain the corresponding six - dimensional force loads; calculate the pose change value of the wind tunnel balance relative to the balance calibration device during the two calibrations of the wind tunnel balance; S10. Modify the test load table for the previous calibration and inspection of the wind tunnel balance according to the pose change value of the wind tunnel balance relative to the balance calibration device during the two calibrations of the wind tunnel balance; S11. Extract the wind tunnel balance formula and the formula for the applied six - dimensional force loads obtained by iterative solution. For the response output voltages of the corresponding component Wheatstone bridges in the test load table for the previous inspection of the wind tunnel balance, iteratively solve to obtain the applied six - dimensional force loads for the previous inspection of the wind tunnel balance; S12. Compare the modified test load table for the previous calibration and inspection of the wind tunnel balance with the solved applied six - dimensional force loads for the previous inspection of the wind tunnel balance to obtain the residuals of each group of six - dimensional force loads, and evaluate the prediction ability of the wind tunnel balance formula obtained from the current calibration in the wind tunnel test in the form of standard deviation.

2. The method for comparative evaluation of wind tunnel balance formulas based on pose transformation correction according to claim 1, characterized in that, The wind tunnel balance formula is: where i, j, and k are the indices of the components of the wind tunnel balance; F i is the load for which the formula for the i-th component of the wind tunnel balance is to be fitted and generated; a i is the main term coefficient of the i-th component; ΔU i is the response output voltage of the i-th component Wheatstone bridge; b i j is the first-order interference correction coefficient of the j-th component load on the i-th component; c i jk are the second-order square term interference coefficient and the cross-term interference correction coefficient of the j-th and k-th components with respect to the i-th component; P j and P k are the loads of the j-th and k-th components of the wind tunnel balance.

3. The method for comparative evaluation of wind tunnel balance formulas based on pose transformation correction according to claim 2, characterized in that, The formula for iteratively solving the applied six - dimensional force loads is: F i0 = a i * ΔU i Where h is the number of iterative calculations, and the sequential values during the iterative process are 1, 2, 3, 4, 5, 6, 7 respectively, and q = h - 1; F i0 is the load obtained by multiplying the main term coefficient and the output voltage of the Wheatstone bridge response for the i-th component; F ih is the load for the h-th iterative calculation of the i-th component; P jq and P kq are the loads that have been calculated for the j-th and k-th components of the wind tunnel balance in the q-th iteration.

4. The method for comparative evaluation of wind tunnel balance formulas based on pose transformation correction according to claim 3, characterized in that, The formula for calculating the standard deviation of each component of the wind tunnel balance is: Where m is the index of each group of loads in the test load table; n is the number of groups of loads in the test load table; σ i is the standard deviation of the i-th component of the wind tunnel balance; J im is the load value of the i-th component and the m-th group in the test load table; JJ im is the load value of the m-th group of the i-th component obtained by calculation; S i is the design load of the i-th component of the wind tunnel balance.

5. The method for comparative evaluation of wind tunnel balance formulas based on pose transformation correction according to claim 4, characterized in that, The formula for calculating the relative deviation of the six - component main - term coefficients is: where δ i is the relative deviation of the main term coefficient of the i-th component; a i1 is the main term coefficient of the i-th component of the wind tunnel balance formula obtained from this calibration; a i2 is the main term coefficient of the i-th component of the wind tunnel balance formula obtained from the previous calibration.

6. The method for comparative evaluation of wind tunnel balance formulas based on pose transformation correction according to claim 5, characterized in that, The formula for the pose of the wind tunnel balance relative to the balance calibration device during the two calibrations of the wind tunnel balance is: Wherein, Lx, Ly, and Lz are the three linear displacement change values of the wind tunnel balance relative to the balance calibration device along the X, Y, and Z axes of the right - hand coordinate system during two calibrations of the wind tunnel balance; α, β, and γ are the three angular displacement change values of the wind tunnel balance relative to the balance calibration device around the Z, Y, and X axes of the right - hand coordinate system during two calibrations of the wind tunnel balance; Y, M z y , M x y , X y and Z y are the normal force, pitching moment, rolling moment, axial force, and lateral force calculated when the unit loading normal force in the calibration load table; Mz and M x Mz are the pitching moment and rolling moment calculated when the unit loading pitching moment in the calibration load table; Z and M x z are the lateral force and rolling moment calculated when the unit loading lateral force in the calibration load table.

7. The method for comparative evaluation of a wind tunnel balance formula based on pose conversion correction according to claim 6, wherein, The formula for modifying the test load table for the previous calibration and inspection of the wind tunnel balance is: Y m1 = Y m0 ,M zm1 = M zm0 + Y m0 * Lx,M xm1 = M xm0 ,X m1 = X m0 ,Z m1 = Z m0 ,M ym1 = M ym0 - Z m0 * Lx Y m2 = Y m1 , M zm2 = M zm1 + X m1 * Ly, M xm2 = M xm1 + Z m1 * Ly,X m2 = X m1 ,Z m2 = Z m1 ,M ym2 = M ym1 Y m3 = Y m2 ,M zm3 = M zm2 ,M xm3 = M xm2 -Y m2 *Lz,X m3 = X m2 ,Z m3 = Z m2 ,M ym3 = M ym2 -X m2 * Lz Y m4 = Y m3 * cosα + X m3 * sinα, M zm4 = M zm3 , M xm4 = M xm3 * cosα + M ym3 * sinα, X m4 = X m3 * cosα - Y m3 * sinα, Z m4 = Z m3 , M ym4 = M ym3 * cosα - M xm3 * sinα Y m5 = Y m4 , M zm5 = M zm4 * cosβ - M xm4 * sinβ, M xm5 = M xm4 * cosβ - M zm4 * sinβ, X m5 = X m4 * cosβ + Z m4 * sinβ, Z m5 = Z m4 * cosβ - X xm4 * sinβ, M ym5 = M ym4 Y m6 = Y m5 * cosγ + Z m5 * sinγ, M zm6 = M zm5 * cosγ - M ym5 * sinγ, M xm6 = M xm5 , X m6 = X m5 , Z m6 = Z m5 * cosγ - Y m5 * sinγ, M ym6 = M ym5 * cosγ + M zm5 * sinγ Wherein, Y m0 , M zm0 , M xm0 , X m0 , Z m0 and M ym0 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment of the m-th group in the test load table; Y m1 , M zm1 , M xm1 , X m1 , Z m1 and M ym1 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment of the m-th group in the test load table after load correction Lx; Y m2 , M zm2 , M xm2 , X m2 , Z m2 and M ym2 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment of the m-th group in the test load table after load corrections Lx and Ly; Y m3 , M zm3 , M xm3 , X m3 , Z m3 and M ym3 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment of the m-th group in the test load table after load corrections Lx, Ly, and Lz; Y m4 , M zm4 , M xm4 , X m4 , Z m4 and M ym4 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment of the m-th group in the test load table after load corrections Lx, Ly, Lz, and α; Y m5 , M zm5 , M xm5 , X m5 , Z m5 and M ym5 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment of the m-th group in the test load table after load corrections Lx, Ly, Lz, α, and β; Y m6 , M zm6 , M xm6 , X m6 , Z m6 and M ym6 are the normal force, pitching moment, rolling moment, axial force, lateral force, and yaw moment of the m-th group in the test load table after load corrections Lx, Ly, Lz, α, β, and γ.

8. An electronic device, wherein, It includes a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, it implements the steps of a method for comparative evaluation of a wind tunnel balance formula based on pose - transformation correction according to any one of claims 1 - 7.

9. A computer-readable storage medium having a computer program stored thereon, wherein, When the computer program is executed by a processor, it implements a method for comparative evaluation of a wind tunnel balance formula based on pose conversion correction as described in any one of claims 1-7.

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