Equipment shot vibration test atlas digital conversion method

Abstract

The invention relates to a digital conversion method for an equipment shot vibration test atlas, and belongs to the technical field of aviation environment adaptability. The invention discloses an equipment shot vibration test spectrum digital conversion method. The method comprises the following steps: (1) intercepting a shot vibration test quantity value in GJB GJB 150.20 A Military Equipment Laboratory Environmental Test Method: Shooting Vibration Test to calculate a related spectrum; (2) using a CAD drawing tool to determine a horizontal and vertical coordinate transformation relation; (3) selecting digital fitting coordinate points on the related atlas; and (4) digitally fitting. The method has the following advantages that the calculation efficiency of the test parameters is improved, the manual measurement error is reduced, the accurate shot vibration test quantity value of the equipment is obtained, and support is provided for verifying the anti-shot vibration capacity of the equipment.

Description

Technical Field

[0001] The invention relates to a method for digital conversion of equipment gun vibration test graphs, belonging to the technical field of aviation environment adaptability. Background Art

[0002] In order to verify the ability of equipment to maintain structural and functional integrity when it encounters repeated shock / transient vibration in a working environment subjected to continuous small-caliber artillery fire, GJB 150.20A "Military Equipment Laboratory Environmental Test Methods Part 20: Artillery Vibration Test" provides a calculation method for artillery vibration. The test spectrum involved in this calculation method includes: the attenuation of the test magnitude caused by the projection parameters of the gun (see Appendix Figure 1 ), the test level attenuation caused by the equipment mass (see Appendix Figure 2 ), the test magnitude attenuation caused by the depth parameter (see Appendix Figure 3 ), the attenuation of vibration magnitude caused by the increase of muzzle distance vector (see Appendix Figure 4 ), the attenuation of the peak value of the bombardment vibration as the vector distance increases (see Appendix Figure 5 ). Some parameters in this calculation method need to be obtained by manual measurement in the spectrum, but the error of manual measurement is relatively large. Summary of the invention

[0003] The purpose of the present invention is to provide a method for digital conversion of equipment artillery vibration test graphs, to convert the test graphs involved in the calculation method of artillery vibration in GJB 150.20A "Military Equipment Laboratory Environmental Test Method Part 20: Artillery Vibration Test" into data, to fit them into corresponding calculation models, to improve the calculation efficiency of test parameters, to reduce manual measurement errors, to obtain accurate artillery vibration test values ​​for equipment, and to provide support for verifying the equipment's ability to resist artillery vibration.

[0004] In order to achieve the above object, the present invention adopts the following technical scheme: a method for digital conversion of equipment cannon vibration test spectrum, comprising the following steps:

[0005] (1) Extract the relevant graphs of the calculation of the value of the artillery vibration test in GJB GJB 150.20A "Military Equipment Laboratory Environmental Test Methods Part 20: Artillery Vibration Test";

[0006] (2) Use CAD drawing tools to determine the transformation relationship between horizontal and vertical coordinates;

[0007] (3) Selecting digital fitting coordinate points on the relevant spectrum;

[0008] (4) Digital fitting.

[0009] Preferably, in step (2), the horizontal and vertical coordinate transformation relationship is determined according to the two-point formula:

[0010] y=[(y2-y1) / (x2-x1)]*(x-x1)+y1

[0011] Among them, x1 and y1 are the horizontal and vertical coordinates of a point in the equipment cannon vibration test map, x2 and y2 are the horizontal and vertical coordinates of another point in the equipment cannon vibration test map; x and y are CAD coordinates.

[0012] Preferably, of the two selected points, one is the 0 point on the coordinates, and the other is a point with a clear scale and as far away as possible.

[0013] Preferably, in step (4), the attenuation spectrum of the test level caused by the projection parameters of the gun is digitally converted:

[0014] f(x)=-3.862×10 -11 x 6 +1.017×10 -8 x 5 +-1.036×10 -6 x 4 +5.202×10 -5 x 3 +-0.003791x

[0015] 2 +0.0592x

[0016] x: Projection parameter of the gun (h / c)

[0017] f(x): attenuation of the test level (dB).

[0018] Preferably, the test magnitude attenuation spectrum caused by the equipment quality is digitally converted:

[0019] Number of cells - Product quality:

[0020] z=10e 0.2302x

[0021] x: the number of cells

[0022] z: Product mass (lbs)

[0023] Number of cells - attenuation of test level:

[0024] f(x)=-1.489×10 -9 x 9 +1.65×10 -7 x 8 -7.363×10 -6 x 7 +0.0001674x 6 -0.002019x 5 +0.0

[0025] 1211x 4 -0.02884x 3 -0.05478x 2 +0.1946x

[0026] x: the number of cells

[0027] f(x): attenuation of the test level (dB).

[0028] Preferably, the test magnitude attenuation spectrum caused by the depth parameter is digitally converted:

[0029] f(x)=-1.33×10 -14 x 8 +7.35×10 -12 x 7 -1.713×10 -9 x 6 +2.23×10 -7 x 5 -1.829×10 -5 x 4 +

[0030] 0.001007x 3 -0.0356x 2 +0.4467x

[0031] x: depth parameter (cm)

[0032] f(x): test level attenuation (dB).

[0033] Preferably, the increase of the muzzle distance vector causes a digital conversion of the attenuation spectrum of the vibration magnitude:

[0034] f(x,y)=-22.11-0.03782x+0.07498y+0.0008472x 2 +7.03×10 -5 xy-6.522×10 - 5 y 2 -1.463

[0035] ×10 -5 x 3 -4.699×10 -6 x 2 y+1.113×10 -7 xy 2 +8.145×10 -8 x 4 +2.133×10 -8 x3 y+1.516×10 -9 x 2 y 2 -1.475×10 -10 x 5 -2.811×10 -11 x 4 y-4.167×10 -12 x 3 y 2

[0036] x: distance vector (cm)

[0037] y: vibration frequency (Hz)

[0038] f(x,y): Vibration attenuation (dB).

[0039] Preferably, the attenuation spectrum caused by the increase of the bombardment vibration peak value with the vector distance is digitally converted:

[0040] f(x,y)=-12.94-0.002942x-0.08451y-0.001695x 2 +0.001724xy+0.0003863y 2 +1.10

[0041] 1×10 -5 x 3 -7.232×10 -6 x 2 y-1.065×10 -5 xy 2 +4.137×10 -6 y 3 -2.8×10 -8 x 4 +1.822×10 -8 x 3 y+1.73×10 -8 x 2 y 2 +2.435×10 -8 xy 3 -2.068×10 -8 y 4 +2.614×10 -11 x 5 -2.094×10 -11 x ^4 *y-3.412×10 -12 x 3 y 2 -2.637×10 -11 x 2y 3 -1.493×10 -11 xy 4 +2.414×10 -11 y 5

[0042] x: distance vector (cm)

[0043] y: vibration frequency (Hz)

[0044] f(x,y): Attenuation of vibration peak (dB).

[0045] Compared with the prior art, the present invention has the following advantages: improving the calculation efficiency of test parameters, reducing manual measurement errors, obtaining accurate blast vibration test values ​​of equipment, and providing support for verifying the equipment's ability to resist blast vibration. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 It is the test spectrum in the background technology of the present invention (the attenuation of the test magnitude caused by the projection parameters of the gun);

[0047] Figure 2 It is the test spectrum in the background technology of the present invention (the test magnitude attenuation caused by the equipment quality);

[0048] Figure 3 is the test spectrum in the background technology of the present invention (the test magnitude attenuation caused by the depth parameter);

[0049] Figure 4 It is the test spectrum in the background technology of the present invention (the attenuation of the vibration magnitude caused by the increase of the muzzle distance vector);

[0050] Figure 5 It is the test spectrum in the background technology of the present invention (the attenuation of the peak value of the shelling vibration caused by the increase of the vector distance). DETAILED DESCRIPTION

[0051] The present invention is further described below: A method for digital conversion of equipment blast test spectrum comprises the following steps:

[0052] (1) Extract the relevant graphs of the calculation of the value of the artillery vibration test in GJB GJB 150.20A "Military Equipment Laboratory Environmental Test Methods Part 20: Artillery Vibration Test", see the attached Figure 1 To Attachment Figure 5 ;

[0053] (2) Use CAD drawing tools to determine the transformation relationship between horizontal and vertical coordinates;

[0054] Use CAD to open the relevant atlas, and after moving and rotating, align the (0,0) coordinate of the atlas with the (0,0) coordinate of CAD, and align the x and y axes with the x and y axes of CAD;

[0055] Although the x and y axes of the atlas are aligned with the x and y axes in CAD, their sizes are not consistent. You need to select two points and determine the coordinate transformation relationship based on the two-point formula:

[0056] y=[(y2-y1) / (x2-x1)]*(x-x1)+y1

[0057] Select two points, one is the 0 point on the coordinates, and the other is a point with clear scale and as far as possible;

[0058] (3) Selecting digital fitting coordinate points on the relevant spectrum;

[0059] When selecting fitting points, in order to ensure the overall accuracy of the fitting expression, points need to be evenly selected on the curve. At the same time, some local points need to be frequently selected. In the coordinate range frequently used by relevant personnel, the density of points should be increased to improve the accuracy of fitting in this area. When selecting points, after zooming in in CAD, it will be found that the curve has thickness. Therefore, the geometric center coordinates of the pixel points that make up the curve are taken as the (x, y) coordinates of a point on the curve in CAD, and then converted into the (x, y) coordinates in the picture according to the coordinate transformation relationship, and then the obtained points are fitted;

[0060] (4) Digital fitting

[0061] Polynomial fitting can approximate various curves, so polynomial fitting (least square method) is selected. In determining the degree of the polynomial, use polynomials of different degrees to approximate the curve or surface, and select the calculation expression with the smallest error. Through digital fitting, the attached Figure 1 To Attachment Figure 5 The calculation expression is as follows:

[0062] 1) Digital conversion of the attenuation spectrum of the test level caused by the projection parameters of the gun;

[0063] f(x)=-3.862×10 -11 x 6 +1.017×10 -8 x 5 +-1.036×10 -6 x 4 +5.202×10 -5 x 3 +-0.003791x

[0064] 2 +0.0592x

[0065] x: Projection parameter of the gun (h / c)

[0066] f(x): attenuation of the test level (dB)

[0067] 2) Digital conversion of the test magnitude attenuation spectrum caused by equipment mass;

[0068] Number of cells - Product quality:

[0069] z=10e 0.2302x

[0070] x: the number of cells

[0071] z: Product mass (lbs)

[0072] Number of cells - attenuation of test level:

[0073] f(x)=-1.489×10 -9 x 9 +1.65×10 -7 x 8 -7.363×10 -6 x 7 +0.0001674x 6 -0.002019x 5 +0.0

[0074] 1211x 4 -0.02884x 3 -0.05478x 2 +0.1946x

[0075] x: the number of cells

[0076] f(x): attenuation of the test level (dB)

[0077] 3) Digital conversion of the test magnitude attenuation spectrum caused by depth parameters;

[0078] f(x)=-1.33×10 -14 x 8 +7.35×10 -12 x 7 -1.713×10 -9 x 6 +2.23×10 -7 x 5 -1.829×10 -5 x 4 +

[0079] 0.001007x 3 -0.0356x2 +0.4467x

[0080] x: depth parameter (cm)

[0081] f(x): test level attenuation (dB)

[0082] 4) The increase of muzzle distance vector causes the digital conversion of the attenuation spectrum of vibration magnitude;

[0083] f(x,y)=-22.11-0.03782x+0.07498y+0.0008472x 2 +7.03×10 -5 xy-6.522×10 - 5 y 2 -1.463

[0084] ×10 -5 x 3 -4.699×10 -6 x 2 y+1.113×10 -7 xy 2 +8.145×10 -8 x 4 +2.133×10 -8 x 3 y+1.516×10 -9 x 2 y 2 -1.475×10 -10 x 5 -2.811×10 -11 x 4 y-4.167×10 -12 x 3 y 2

[0085] x: distance vector (cm)

[0086] y: vibration frequency (Hz)

[0087] f(x,y): Vibration attenuation (dB)

[0088] 5) Digital conversion of the attenuation spectrum caused by the increase of the shelling vibration peak value with the vector distance.

[0089] f(x,y)=-12.94-0.002942x-0.08451y-0.001695x 2 +0.001724xy+0.0003863y 2 +1.10

[0090] 1×10 -5 x 3 -7.232×10 -6 x 2 y-1.065×10 -5 xy 2 +4.137×10 -6 y 3 -2.8×10 -8 x 4 +1.822×10 -8 x 3 y+1.73×10 -8 x 2 y 2 +2.435×10 -8 xy 3 -2.068×10 -8 y 4 +2.614×10 -11 x 5 -2.094×10 -11 x ^4 *y-3.412×10 -12 x 3 y 2 -2.637×10 -11 x 2 y 3 -1.493×10 -11 xy 4 +2.414×10 -11 y 5

[0091] x: distance vector (cm)

[0092] y: vibration frequency (Hz)

[0093] f(x,y): Attenuation of vibration peak (dB).

[0094] The above embodiments are merely preferred implementation schemes of the present invention. Any extensions, modifications, etc. made by ordinary technicians in this field without departing from the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for digital conversion of equipment cannon vibration test spectrum, characterized in that: The following steps are involved: (1) Extract the relevant graphs of the calculation of the value of the artillery vibration test in GJB GJB 150.20A "Military Equipment Laboratory Environmental Test Methods Part 20: Artillery Vibration Test"; (2) Use CAD drawing tools to determine the transformation relationship between horizontal and vertical coordinates; (3) Selecting digital fitting coordinate points on the relevant spectrum; (4) Digital fitting.

2. The method for digital conversion of equipment cannon vibration test spectrum according to claim 1 is characterized in that: In step (2), the horizontal and vertical coordinate transformation relationship is determined according to the two-point formula: y=[(y2-y1) / (x2-x1)]*(x-x1)+y1 Among them, x1 and y1 are the horizontal and vertical coordinates of a point in the equipment cannon vibration test map, x2 and y2 are the horizontal and vertical coordinates of another point in the equipment cannon vibration test map; x and y are CAD coordinates.

3. The method for digital conversion of equipment gun vibration test spectrum according to claim 2 is characterized in that: Select two points, one of which is the 0 point on the coordinate system, and the other is a point with a clear scale and as far away as possible.

4. The method for digital conversion of equipment cannon vibration test spectrum according to claim 1 is characterized in that: In step (4), the attenuation spectrum of the test level is digitally converted due to the projection parameters of the gun: f(x)=-3.862×10 -11 x 6 +1.017×10 -8 x 5 +-1.036×10 -6 x 4 +5.202×10 -5 x 3 +-0.003791x 2 +0.0592x x: Projection parameter of the gun (h / c) f(x): attenuation of the test level (dB).

5. The method for digital conversion of equipment cannon vibration test spectrum according to claim 1 is characterized in that: Digital conversion of the test magnitude attenuation spectrum caused by equipment mass: Number of cells-product quality: z=10e 0.2302x x: the number of cells z: Product mass (lbs) Number of cells - attenuation of test level: f(x)=-1.489×10 -9 x 9 +1.65×10 -7 x 8 -7.363×10 -6 x 7 +0.0001674x 6 -0.002019x 5 +0.0 1211x 4 -0.02884x 3 -0.05478x 2 +0.1946x x: the number of cells f(x): attenuation of the test level (dB).

6. The method for digital conversion of equipment cannon vibration test spectrum according to claim 1 is characterized in that: Digital conversion of the test magnitude attenuation spectrum caused by depth parameters: f(x)=-1.33×10 -14 x 8 +7.35×10 -12 x 7 -1.713×10 -9 x 6 +2.23×10 -7 x 5 -1.829×10 -5 x 4 + 0.001007x 3 -0.0356x 2 +0.4467x x: depth parameter (cm) f(x): test level attenuation (dB).

7. The method for digital conversion of equipment cannon vibration test spectrum according to claim 1 is characterized in that: The increase of muzzle distance vector causes the digital conversion of the attenuation spectrum of vibration magnitude: f(x,y)=-22.11-0.03782x+0.07498y+0.0008472x 2 +7.03×10 -5 xy-6.522×10 -5 y 2 -1.463 ×10 -5 x 3 -4.699×10 -6 x 2 y+1.113×10 -7 xy 2 +8.145×10 -8 x 4 +2.133×10 -8 x 3 y+1.516×10 - 9 x 2 y 2 -1.475×10 -10 x 5 -2.811×10 -11 x 4 y-4.167×10 -12 x 3 y 2 x: distance vector (cm) y: vibration frequency (Hz) f(x,y): Vibration attenuation (dB).

8. The method for digital conversion of equipment cannon vibration test spectrum according to claim 1 is characterized in that: Digital conversion of the attenuation spectrum caused by the increase of the peak value of the shelling vibration with the vector distance: f(x,y)=-12.94-0.002942x-0.08451y-0.001695x 2 +0.001724xy+0.0003863y 2 +1.10 1×10 -5 x 3 -7.232×10 -6 x 2 y-1.065×10 -5 xy 2 +4.137×10 -6 y 3 -2.8×10 -8 x 4 +1.822×10 - 8 x 3 y+1.73×10 -8 x 2 y 2 +2.435×10 -8 xy 3 -2.068×10 -8 y 4 +2.614×10 -11 x 5 -2.094×10 -11 x ^4 *y-3.412×10 -12 x 3 y 2 -2.637×10 -11 x 2 y 3 -1.493×10 -11 xy 4 +2.414×10 -11 y 5 x: distance vector (cm) y: vibration frequency (Hz) f(x,y): Attenuation of vibration peak (dB).

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