A general modeling method for wheat grains

Abstract

The present invention discloses a universal modeling method for wheat grain particles, comprising: step one, selecting a plurality of wheat grains of a variety to be modeled, and measuring the three-axis dimensions of each wheat grain respectively; step two, taking a double ellipsoid model as a universal model for wheat grains, and determining the size parameters of the double ellipsoid model according to the three-axis dimensions of the wheat grains; step three, establishing a single ellipsoid model in a spatial coordinate system, and performing sphere filling in the single ellipsoid model to obtain a single ellipsoid combination model; performing spatial coordinate transformation on the single ellipsoid combination model to obtain a double ellipsoid combination model of the wheat grains; wherein the single ellipsoid model is one of the two ellipsoids in the double ellipsoid model; and generating a double ellipsoid combination model of the wheat grains of corresponding sizes according to the three-axis size distribution interval of the wheat grains to obtain a group of wheat grain particle models.

Description

Technical Field

[0001] The invention relates to the field of wheat grain modeling and analysis, and in particular to a universal modeling method for wheat grain particles. Background Art

[0002] As the main food crop in the world, wheat is widely planted in most parts of China in a mechanized manner. During its sowing, harvesting, grading, storage and other operations, there is always interaction between particles and particles, and between particles and mechanical parts. In order to study the interaction between wheat seed particles and mechanical parts and optimize the structure and working parameters of mechanical parts, it is very necessary to accurately establish a wheat seed particle model. The main methods for wheat seed particle modeling include the combined sphere method, the polyhedron method and the hyperellipsoid method. The combined sphere modeling method refers to the use of multiple spheres to fill the wheat seeds to achieve modeling, but how to fill the wheat seeds with balls, the size, quantity and position of the filling balls need to be studied in depth. Summary of the invention

[0003] The purpose of the present invention is to provide a universal modeling method for wheat grain particles, which can establish a universal and accurate wheat seed particle model.

[0004] The technical solution provided by the present invention is:

[0005] A general modeling method for wheat grain particles comprises the following steps:

[0006] Step 1: Select multiple wheat grains of the variety to be modeled, and measure the three-axis dimensions of each wheat grain respectively;

[0007] Step 2: using a double ellipsoid model as a universal model of wheat grains, and determining size parameters of the double ellipsoid model according to the three-axis dimensions of the wheat grains;

[0008] Step 3: Establish a single ellipsoid model in the spatial coordinate system, and perform sphere filling in the single ellipsoid model to obtain a single ellipsoid combination model; perform spatial coordinate transformation on the single ellipsoid combination model to obtain a double ellipsoid combination model of wheat grains;

[0009] Wherein, the single ellipsoid model is one of the two ellipsoids in the double ellipsoid model;

[0010] And according to the three-axis size distribution interval of the wheat grains, a double ellipsoid combination model of the wheat grains of corresponding sizes is generated to obtain a wheat grain particle model group.

[0011] Preferably, in step 2, the size parameters of the double ellipsoid model are:

[0012] a=0.5L,

[0013]

[0014]

[0015]

[0016] Among them, a is the major semi-axis of the single ellipsoid in the double ellipsoid model, b is the median semi-axis of the single ellipsoid in the double ellipsoid model, c is the minor semi-axis of the single ellipsoid in the double ellipsoid model, θ is the angle between the double ellipsoids; L is the length of the wheat grain, W is the width of the wheat grain, and T is the thickness of the wheat grain.

[0017] Preferably, the double ellipsoid combination model is a 13-sphere combination model, a 17-sphere combination model, a 25-sphere combination model or a 33-sphere combination model.

[0018] Preferably, the modeling method of the 13-ball combination model is:

[0019] In a Cartesian coordinate system, a single ellipsoid model is established with the coordinate origin as the center of the single ellipsoid; after filling the first to seventh spheres in the single ellipsoid model, a spatial coordinate transformation is performed to obtain the 13-sphere combination model;

[0020] Among them, the X-axis of the coordinate system is the direction of the long axis of the single ellipsoid, and the long axis of the single ellipsoid is 2a; the Y-axis of the coordinate system is the direction of the short axis of the single ellipsoid, and the short axis of the single ellipsoid is 2c; the Z-axis of the coordinate system is the direction of the median axis of the single ellipsoid, and the median axis of the single ellipsoid is 2b;

[0021] The coordinates of the first sphere are: (0,0,0), and the radius of the first sphere is: c;

[0022] The coordinates of the second sphere are: (0, 0, (b 2 -c 2 ) / b), the radius of the second sphere is: c 2 / b;

[0023] The coordinates of the third sphere are: (0, 0, -(b 2 -c 2 ) / b), the radius of the third sphere is: c 2 / b;

[0024] The coordinates of the fourth sphere are: ((a 2 -c 2 ) / a, 0, 0), the radius of the fourth sphere is: c 2 / a;

[0025] The coordinates of the fifth sphere are: (-(a 2 -c 2 ) / a, 0, 0), the radius of the fifth sphere is: c 2 / a;

[0026] The coordinates of the sixth sphere are: ((a 2 -c 2 ) / 2a, 0, 0), the radius of the sixth sphere is:

[0027] The coordinates of the seventh sphere are: (-(a 2 -c 2 ) / 2a, 0, 0), the radius of the seventh sphere is:

[0028] Preferably, the modeling method of the 17-ball combination model is:

[0029] The 13-sphere combination model is established, and after the eighth sphere and the ninth sphere are filled in the single ellipsoid of the 13-sphere model, a spatial coordinate transformation is performed to obtain the 17-sphere combination model; wherein:

[0030] The coordinates of the eighth sphere are: The radius of the eighth sphere is

[0031] The coordinates of the ninth sphere are: The radius of the ninth sphere is

[0032] Preferably, the modeling method of the 25-ball combination model is:

[0033] The 17-ball combination model is established, and after the tenth to thirteenth balls are filled in the single ellipsoid of the 17-ball model, spatial coordinate transformation is performed to obtain the 25-ball combination model; wherein:

[0034] The coordinates of the tenth sphere are: The radius of the tenth sphere is

[0035] The coordinates of the eleventh sphere are: The radius of the eleventh sphere is

[0036] The coordinates of the twelfth sphere are: The radius of the twelfth sphere is

[0037] The coordinates of the thirteenth sphere are: The radius of the thirteenth sphere is

[0038] Preferably, the modeling method of the 33-ball combination model is:

[0039] The 25-sphere combination model is established, and after the fourteenth to seventeenth spheres are filled in the single ellipsoid of the 25-sphere model, spatial coordinate transformation is performed to obtain the 33-sphere combination model; wherein:

[0040] The coordinates of the fourteenth sphere are: The radius of the fourteenth sphere is

[0041] The coordinates of the fifteenth sphere are: The radius of the fifteenth sphere is

[0042] The coordinates of the sixteenth sphere are: The radius of the sixteenth sphere is

[0043] The coordinates of the seventeenth sphere are: The radius of the seventeenth sphere is

[0044] Preferably, the spatial coordinate transformation is performed according to the following formula:

[0045] (x″′ y″′ z″′ 1)=(xyz 1)·R(±α);

[0046] in,

[0047]

[0048] Wherein, (xyz 1) is the coordinate before spatial transformation, (x″′ y″′ z″′ 1) is the coordinate after spatial transformation, R(±α) is the spatial coordinate transformation matrix; α represents the rotation transformation angle, and its value is θ / 2.

[0049] The beneficial effects of the present invention are:

[0050] 1. The wheat grain modeling method provided by the present invention performs shape analysis on multiple main wheat varieties. Therefore, the wheat grain modeling method of the present invention has wide applicability and strong versatility.

[0051] 2. The wheat grain modeling method provided by the present invention uses a double ellipsoid particle model to describe the wheat grain. Compared with other models, the double ellipsoid model has a smaller error with the actual wheat grain shape and a higher modeling accuracy.

[0052] 3. The present invention uses a combination ball to establish a wheat grain model, and establishes the relationship between the double ellipsoid particle model and the three-axis dimensions of the real wheat grain. The user only needs to measure the three-axis dimensions of the corresponding wheat variety and select the number of filling balls of the combination ball model to obtain the corresponding particle model. The operation is simple and quick.

[0053] 4. The wheat grain modeling method provided by the present invention also has certain applicability and guiding significance for other crop grains of similar shapes, such as barley, rice, oats, highland barley, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is the triaxial size of the wheat seeds described in the present invention.

[0055] Figure 2 This is the double ellipsoid model of wheat seeds described in the present invention.

[0056] Figure 3(a)-3(d) This is the coordinate transformation of the double ellipsoid particle model described in the present invention.

[0057] FIG. 4( a ) is a double ellipsoid 13-sphere combination model according to the present invention.

[0058] FIG4( b ) is a double ellipsoid 17-sphere combination model according to the present invention.

[0059] FIG4( c ) is a double ellipsoid 25-sphere combination model of the present invention.

[0060] FIG4( d ) is a double ellipsoid 33-sphere combination model according to the present invention.

[0061] Figure 5 This is a comparison chart between the simulation results and the test results of the self-flow screening of the dwarf 58 double ellipsoid combination model described in the present invention.

[0062] Figure 6 This is a comparison chart between the simulation results and the test results of the self-flow screening of the Zhongmai 175 double ellipsoid combination model described in the present invention.

[0063] Figure 7 This is a comparison chart between the simulation results and the test results of the self-flow screening of the cotton and wheat 51 double ellipsoid combination model described in the present invention.

[0064] Figure 8 This is a comparison chart between the self-flow screening simulation results and the test results of the Zhengmai 9023 double ellipsoid combination model described in the present invention.

[0065] Fig. 9 This is a comparison chart between the simulation results and the test results of the static stacking angle of the dwarf 58 double ellipsoid combination model described in the present invention.

[0066] Fig.10 This is a comparison chart between the simulation results and the test results of the static stacking angle of the Zhongmai 175 double ellipsoid combination model described in the present invention.

[0067] Fig.11 This is a comparison chart between the simulation results and the test results of the static stacking angle of the cotton and wheat 51 double ellipsoid combination model described in the present invention.

[0068] Fig.12 This is a comparison chart between the simulation results and the test results of the static stacking angle of the Zhengmai 9023 double ellipsoid combination model described in the present invention. DETAILED DESCRIPTION

[0069] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0070] like Figure 1-2 As shown, the general modeling method of wheat grain particles provided by the present invention comprises:

[0071] 1. Select multiple wheat grains of the variety to be modeled, measure the three-axis dimensions of each wheat grain respectively, and count the interval distribution of the three-axis dimensions of the wheat grains. The three-axis dimensions are the length, width and thickness of the wheat size. Among them: the thickness T is defined from the ventral groove to the ridge of the wheat seed, the width W is defined on both sides of the ventral groove, and the length L is defined along the ventral groove.

[0072] 2. According to the shape and size of wheat grains, the double ellipsoid model is used as a general model to describe wheat grains, and the relationship between the three-axis dimensions of wheat grains and the dimensions of the double ellipsoid particle model is established to obtain the size value of a single ellipsoid.

[0073] Define the major semi-axis of a single ellipsoid in the double ellipsoid model as a, the middle semi-axis as b, and the minor semi-axis as c. The length L of the wheat seed is consistent with the length of the ellipsoid, that is,

[0074] a=0.5L

[0075] In △DEF, the relationship between the double ellipsoid particle model parameters and the wheat grain parameters can be approximately established:

[0076]

[0077]

[0078]

[0079] Among them, θ is the angle between the two ellipsoids; L is the length of the wheat grain, W is the width of the wheat grain, and T is the thickness of the wheat grain.

[0080] 3. According to the size of the double ellipsoid, first fill the spheres in the single ellipsoid, then transform the spatial coordinates of the combined spheres in the single ellipsoid to obtain the double ellipsoid combined sphere model. After the single ellipsoid is established, the process of obtaining the double ellipsoid model by coordinate transformation of the single ellipsoid is as follows: Figure 3(a)-3(d) shown.

[0081] The double ellipsoid combination model is a 13-sphere combination model, a 17-sphere combination model, a 25-sphere combination model or a 33-sphere combination model.

[0082] 4. According to the actual characteristic size distribution of wheat grains, generate a population of wheat grain models of corresponding sizes.

[0083] As shown in Figure 4(a), the modeling process of the 13-ball combination model is:

[0084] In the Cartesian coordinate system, the coordinate origin is taken as the center of the single ellipsoid, and a single ellipsoid model is established; the major axis of the single ellipsoid is 2a, the median axis is 2b, and the minor axis is 2c. The major axis of the ellipsoid is defined as the X axis, the minor axis is the Y axis, and the median axis is the Z axis.

[0085] With the coordinate origin (0,0,0) of the ellipsoid model as the center, fill the first sphere in the ellipsoid model so that it is tangent to the minor axis of the ellipsoid in the Y direction;

[0086] The coordinates of the first ball are: (0,0,0),

[0087] The radius of the first sphere is: c.

[0088] Fill the second sphere in the positive direction of the Z axis of the ellipsoid so that it is tangent to the ellipsoid in the positive direction of the Z axis at point (0, 0, c); then

[0089] The coordinates of the second sphere are: (0, 0, (b 2 -c 2 ) / b),

[0090] The radius of the second sphere is: c 2 / b.

[0091] Similarly, fill the third sphere in the negative direction of the Z axis of the ellipsoid so that it is tangent to the ellipsoid in the negative direction of the Z axis at point (0, 0, c);

[0092] The coordinates of the third sphere are: (0, 0, -(b 2 -c 2 ) / b),

[0093] The radius of the third sphere is: c 2 / b.

[0094] Fill the fourth sphere in the positive direction of the X-axis of the ellipsoid so that it is tangent to the ellipsoid in the positive direction of the X-axis at point (a, 0, 0); then

[0095] The coordinates of the fourth sphere are: ((a 2 -c 2 ) / a,0,0),

[0096] The radius of the fourth sphere is: c 2 / a.

[0097] Similarly, fill the fifth sphere in the negative direction of the X-axis of the ellipsoid so that it is tangent to the ellipsoid in the negative direction of the X-axis at point (-a, 0, 0); then

[0098] The coordinates of the fifth sphere are: (-(a 2 -c 2 ) / a,0,0),

[0099] The radius of the fifth sphere is: c 2 / a.

[0100] Fill the sixth sphere between the first sphere and the fourth sphere, and make the sixth sphere tangent to the ellipsoid; we can get

[0101] The coordinates of the sixth sphere are: ((a 2 -c 2 ) / 2a,0,0),

[0102] The radius of the sixth sphere is:

[0103] Similarly, fill the seventh sphere between the first sphere and the fifth sphere, and make the seventh sphere tangent to the ellipsoid; we can get

[0104] The coordinates of the seventh sphere are: (-(a 2 -c 2 ) / 2a,0,0),

[0105] The radius of the seventh sphere is:

[0106] Then the combined model of the above seven balls is transformed into spatial coordinates. The specific transformation process is as follows:

[0107] Since the ellipsoid rotates a certain angle around the rotation axis perpendicular to the OYZ plane and Z = (b2-c2) / b, the rotation axis needs to be translated to the coordinate origin, as shown in Figure 3(b).

[0108] Then the coordinate translation transformation is: (x′ y′ z′ 1) = (xyz 1)·T.

[0109] Among them, the translation coordinate transformation matrix T can be expressed as:

[0110]

[0111] After the coordinate translation transformation, the rotation axis coincides with the X-axis. According to the right-hand rule, the rotation transformation is performed in the positive and negative directions respectively. The rotation transformation angle is α, and the value of α is θ / 2, as shown in Figure 3(c).

[0112] That is, the coordinate rotation transformation is: (x″ y″ z″ 1) = (x′ y′ z′ 1)·R x (±α).

[0113] Among them, the rotation transformation R x (±α) can be expressed as:

[0114]

[0115] After that, the double ellipsoid model obtained by rotation is translated upward to the original position, that is, the coordinate translation transformation is:

[0116] (x″′ y″′ z″′ 1)=(x″ y″ z″ 1)·T -1 .

[0117] Among them, the translation coordinate transformation matrix T -1 It can be expressed as:

[0118]

[0119] In summary, the ellipsoid coordinates after coordinate transformation can be expressed as:

[0120] (x″′ y″′ z″′ 1)=(xyz 1)·R(±α).

[0121] Among them, the coordinate transformation matrix R (±α) can be expressed as the product of the above three coordinate transformation matrices

[0122] R(α)=T·R x (α)T -1 .

[0123] That is, the coordinate transformation matrix R(±α) is:

[0124]

[0125]

[0126] After the above seven filling balls are transformed twice, the coordinates of the second ball after the two transformations are consistent, so a thirteen-ball model can be obtained. The coordinates and radius of each ball after the transformation are:

[0127] The coordinates of the first sphere O0 are The radius is c;

[0128] The coordinates of the second ball O1 are The radius is

[0129] The coordinates of the third sphere O2 are The radius is

[0130] The coordinates of the fourth sphere O3 are The radius is

[0131] The coordinates of the fifth sphere O4 are The radius is

[0132] The coordinates of the sixth sphere O5 are The radius is

[0133] The coordinates of the seventh sphere O6 are The radius is

[0134] The coordinates of the eighth sphere O7 are The radius is c;

[0135] The coordinates of the ninth sphere O8 are The radius is

[0136] The coordinates of the tenth sphere O9 are The radius is

[0137] 11th Ball O 10 The coordinates of The radius is

[0138] 12th Ball O 11 The coordinates of The radius is

[0139] Thirteenth ball O 12 The coordinates of The radius is

[0140] As shown in Figure 4(b), the modeling process of the 17-ball combination model is:

[0141] In order to make the outline of the combined sphere model closer to the double ellipsoid, four spheres are added on the basis of the thirteen spheres. First, the eighth sphere and the ninth sphere are added to the single ellipsoid.

[0142] The eighth sphere coordinates of the single ellipsoid are: The radius is

[0143] The coordinates of the ninth sphere are: The radius is

[0144] After the above coordinate transformation, the fourteenth to seventeenth spheres of the double ellipsoid model can be obtained.

[0145] 14th Ball O 13 The coordinates of The radius is

[0146] 15th Ball O 14 The coordinates of The radius is

[0147] 16th Ball O 15 The coordinates of The radius is

[0148] 17th Ball O 16 The coordinates of The radius is

[0149] As shown in Figure 4(c), the modeling process of the 25-ball combination model is:

[0150] In order to make the outline of the combined sphere model closer to the double ellipsoid, eight spheres are added on the basis of the seventeen spheres. First, the tenth to thirteenth spheres are added to the single ellipsoid.

[0151] The tenth sphere coordinates of a single ellipsoid are: The radius is

[0152] The coordinates of the eleventh sphere are: The radius is

[0153] The coordinates of the twelfth sphere are: The radius is

[0154] The coordinates of the thirteenth sphere are: The radius is

[0155] After the above coordinate transformation, the eighteenth to twenty-fifth spheres of the double ellipsoid model can be obtained.

[0156] 18th Ball O 17 The coordinates of The radius is

[0157] 19th Ball O 18 The coordinates of The radius is

[0158] 20th Ball O 19 The coordinates of The radius is

[0159] 21st Ball O 20 The coordinates of The radius is

[0160] 22nd Ball O 21The coordinates of The radius is

[0161] Twenty-third ball O 22 The coordinates of The radius is

[0162] Twenty-fourth ball O 23 The coordinates of The radius is

[0163] 25th Ball O 24 The coordinates of The radius is

[0164] As shown in Figure 4(d), the modeling process of the 33-ball combination model is:

[0165] In order to make the outline of the combined sphere model closer to the double ellipsoid, eight spheres are added to the twenty-five spheres. First, the fourteenth to seventeenth spheres are added to the single ellipsoid.

[0166] The coordinates of the fourteenth sphere of the single ellipsoid are: The radius is

[0167] The coordinates of the fifteenth sphere are: The radius is

[0168] The coordinates of the sixteenth sphere are: The radius is

[0169] The coordinates of the seventeenth sphere are: The radius is

[0170] After the above coordinate transformation, the twenty-sixth to thirty-third spheres of the double ellipsoid model can be obtained.

[0171] Twenty-sixth ball O 25 The coordinates of The radius is

[0172] Twenty-seventh ball 26 The coordinates of The radius is

[0173] Twenty-eighth ball 27 The coordinates of The radius is

[0174] Twenty-ninth ball O 28 The coordinates of The radius is

[0175] 30th Ball O 29 The coordinates of The radius is

[0176] 31st Ball O 30 The coordinates of The radius is

[0177] Ball 32 O 31 The coordinates of The radius is

[0178] Ball 33 O 32 The coordinates of The radius is

[0179] 12 main wheat varieties were selected from four major wheat growing areas in China. 200 seeds were randomly selected from each of the 12 varieties to analyze their triaxial dimensions and length-to-thickness ratios, and four varieties were selected based on the length-to-thickness ratio for verification (respectively, Examples 1-4).

[0180] Table 1 Characteristic size of wheat grains in domestic wheat growing areas

[0181]

[0182] Example 1

[0183] The geometric modeling method provided by the present invention is used to create 13-ball, 17-ball, 25-ball and 33-ball models of dwarf resistant 58 wheat grains.

[0184] 1. Randomly select 200 seeds, measure their triaxial dimensions and length-to-thickness ratio, and count the triaxial dimension interval distribution of wheat grains, determine that the thickness of the grain is the main dimension, and establish its relationship with the length and width.

[0185] L=(-0.0642T+0.2661)T 4

[0186] W=(-0.0342T+0.1434)T 4

[0187] According to the measured value of the main dimension T=3.158mm, combined with the above relationship, we can obtain: L is 6.302mm, W is 3.521mm; the three-axis dimensions obtained here are the shape dimensions of the wheat grains used for modeling.

[0188] 2. According to the shape and size of wheat grains, the relationship between the three-axis size of wheat grains and the size of the double ellipsoid particle model was established, and the size value of a single ellipsoid and the angle of the double ellipsoid were obtained: a is 3.151mm, b is 1.589mm, c is 1.460mm, and θ is 65.593°.

[0189] 3. Fill a single ellipsoid in the double ellipsoid model with a sphere, then transform the filled sphere into a spatial coordinate to obtain a double ellipsoid combined sphere model, as shown in Table 2.

[0190] Table 2 Coordinates and radius of the center of the spherical model of the Aikang 58 double ellipsoid combination

[0191]

[0192]

[0193] 4. According to the main dimension T follows the normal distribution (3.158, 0.109 2 ) to generate a particle group.

[0194] Example 2

[0195] The geometric modeling method provided by the present invention is used to create 13-ball, 17-ball, 25-ball and 33-ball models of Zhongmai 175 wheat grains.

[0196] 1. Randomly select 200 seeds, measure their triaxial dimensions and length-to-thickness ratio, and count the triaxial dimension interval distribution of wheat grains, determine that the thickness of the grain is the main dimension, and establish its relationship with the length and width.

[0197] L=(-0.0836T+0.3307)T 4

[0198] W=(-0.0407T+0.1647)T 4

[0199] According to the measured value of the main dimension T=3.108mm, combined with the above relationship, we can obtain: L is 6.613mm, W is 3.565mm; the three-axis dimensions obtained here are the shape dimensions of the wheat grains used for modeling.

[0200] 2. According to the shape and size of wheat grains, the relationship between the three-axis size of wheat grains and the size of the double ellipsoid particle model was established, and the size value of a single ellipsoid and the angle of the double ellipsoid were obtained: a is 3.307mm, b is 1.596mm, c is 1.349mm, and θ is 71.103°.

[0201] 3. Fill a single ellipsoid in the double ellipsoid model with a sphere, then transform the filled sphere into a spatial coordinate to obtain a double ellipsoid combined sphere model, as shown in Table 3.

[0202] Table 3 Coordinates and radius of the center of the Mai 175 double ellipsoid combined sphere model

[0203]

[0204]

[0205] 4. According to the main dimension T follows the normal distribution (3.108, 0.156 2 ) to generate a particle group.

[0206] Example 3

[0207] The geometric modeling method provided by the present invention is used to create 13-ball, 17-ball, 25-ball and 33-ball models of Mianmai 51 wheat grains.

[0208] 1. Randomly select 200 seeds, measure their triaxial dimensions and length-to-thickness ratio, and count the triaxial dimension interval distribution of wheat grains, determine that the thickness of the grain is the main dimension, and establish its relationship with the length and width.

[0209] L=(-0.01197T+0.4466)T 4

[0210] W=(-0.0637T+0.2392)T 4

[0211] According to the measured value of the main dimension T=3.009mm, combined with the above relationship, we can obtain: L is 7.085mm, W is 3.896mm; the three-axis dimensions obtained here are the shape dimensions of the wheat grains used for modeling.

[0212] 2. According to the shape and size of wheat grains, the relationship between the three-axis size of wheat grains and the size of the double ellipsoid particle model was established, and the size value and rotation angle of a single ellipsoid were obtained: a is 3.542mm, b is 1.640mm, c is 1.274mm, and θ is 68.313°.

[0213] 3. Fill a single ellipsoid in the double ellipsoid model with a sphere, then transform the filled sphere into a spatial coordinate to obtain a double ellipsoid combined sphere model, as shown in Table 4.

[0214] Table 4 Coordinates and radius of the center of the Mianmai 51 double ellipsoid combined sphere model

[0215]

[0216] 4. According to the main dimension T follows the normal distribution (3.009, 0.157 2 ) to generate a particle group.

[0217] Example 4

[0218] The geometric modeling method provided by the present invention is used to create 13-ball, 17-ball, 25-ball and 33-ball models of Zhengmai 9023 wheat grains.

[0219] 1. Randomly select 200 seeds, measure their triaxial dimensions and length-to-thickness ratio, and count the triaxial dimension interval distribution of wheat grains, determine that the thickness of the grain is the main dimension, and establish its relationship with the length and width.

[0220] L=(-0.01318T+0.4849)T 4

[0221] W=(-0.0562T+0.2097)T 4

[0222] According to the measured value of the main dimension T=2.912mm, combined with the above relationship, we can obtain: L is 7.269mm, W is 3.311mm; the three-axis dimensions obtained here are the shape dimensions of the wheat grains used for modeling.

[0223] 2. According to the shape and size of wheat grains, the relationship between the three-axis size of wheat grains and the size of the double ellipsoid particle model was established, and the size value of a single ellipsoid and the angle of the double ellipsoid were obtained: a is 3.635mm, b is 1.382mm, c is 1.300mm, and θ is 66.686°.

[0224] 3. Fill a single ellipsoid in the double ellipsoid model with a sphere, then transform the filled sphere into a spatial coordinate to obtain a double ellipsoid combined sphere model, as shown in Table 5.

[0225] Table 5 Coordinates and radius of the center of the Zhengmai 9023 double ellipsoid combined sphere model

[0226]

[0227]

[0228] 4. According to the main dimension T follows the normal distribution (2.912, 0.132 2 ) to generate a particle group.

[0229] Verification Example 1

[0230] The feasibility of the modeling schemes in Examples 1 to 4 was verified by gravity screening tests:

[0231] Simulation tests were conducted on the models established for Aikang 58 (Example 1), Zhongmai 175 (Example 2), Mianmai 51 (Example 3) and Zhengmai 9023 (Example 4), respectively, and compared with the actual test results.

[0232] like Figures 5 to 8As shown in the figure, it is the result of simulation data analysis. It can be seen from the results that when the aspect ratio is less than 2.05, the deviation between the simulation result and the actual test value is mainly concentrated in area 4. In this case, the simulation result of 33 balls is closest to the actual test value. When the aspect ratio of the particle model is greater than 2.05, the simulation results of 17 balls, 25 balls and 33 balls tend to be consistent and are closer to the actual test value. However, as the number of filled balls increases, the required simulation time becomes longer. Users can select different numbers of double ellipsoid combined ball models according to their own simulation needs.

[0233] Verification Example 2

[0234] The feasibility of the modeling schemes in Examples 1 to 4 was verified by static stacking angle tests:

[0235] Using a stacking box device, static stacking angle simulation tests were conducted on the models established for Aikang 58 (Example 1), Zhongmai 175 (Example 2), Mianmai 51 (Example 3) and Zhengmai 9023 (Example 4), and the results were compared with the actual test results.

[0236] like Figures 9 to 12 The figure shows the results of simulation data analysis. It can be seen from the results that with the increase in the number of component balls, the simulation values ​​of the static stacking angles of the four particle models gradually decrease, and tend to converge to the actual test values ​​of the static stacking angles. The larger the width-to-thickness ratio of the particles, the closer the convergence value is to the actual test value, indicating that the double ellipsoid combined ball model can accurately simulate the static stacking behavior of wheat seed particle groups. However, as the number of filling balls increases, the required simulation time becomes longer. Users can select different numbers of combined ball models according to their own simulation needs.

[0237] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A general modeling method for wheat grain particles, characterized in that: The steps include: Step 1: Select multiple wheat grains of the variety to be modeled, and measure the three-axis dimensions of each wheat grain respectively; Step 2: using a double ellipsoid model as a universal model of wheat grains, and determining size parameters of the double ellipsoid model according to the three-axis dimensions of the wheat grains; Step 3: Establish a single ellipsoid model in the spatial coordinate system, and perform sphere filling in the single ellipsoid model to obtain a single ellipsoid combination model; perform spatial coordinate transformation on the single ellipsoid combination model to obtain a double ellipsoid combination model of wheat grains; Wherein, the single ellipsoid model is one of the two ellipsoids in the double ellipsoid model; and generating a double ellipsoid combination model of the wheat grains of corresponding sizes according to the three-axis size distribution interval of the wheat grains to obtain a wheat grain particle model population; The double ellipsoid combination model is a 13-sphere combination model, a 17-sphere combination model, a 25-sphere combination model or a 33-sphere combination model; The modeling method of the 13-ball combination model is: In a Cartesian coordinate system, a single ellipsoid model is established with the coordinate origin as the center of the single ellipsoid; after filling the first to seventh spheres in the single ellipsoid model, a spatial coordinate transformation is performed to obtain the 13-sphere combination model; Among them, the X-axis of the coordinate system is the direction of the long axis of the single ellipsoid, and the long axis of the single ellipsoid is 2a; the Y-axis of the coordinate system is the direction of the short axis of the single ellipsoid, and the short axis of the single ellipsoid is 2c; the Z-axis of the coordinate system is the direction of the median axis of the single ellipsoid, and the median axis of the single ellipsoid is 2b; The coordinates of the first sphere are: (0,0,0), and the radius of the first sphere is: c; The coordinates of the second sphere are: (0, 0, (b 2 -c 2 ) / b), the radius of the second sphere is: c 2 / b; The coordinates of the third sphere are: (0, 0, -(b 2 -c 2 ) / b), the radius of the third sphere is: c 2 / b; The coordinates of the fourth sphere are: ((a 2 -c 2 ) / a, 0, 0), the radius of the fourth sphere is: c 2 / a; The coordinates of the fifth sphere are: (-(a 2 -c 2 ) / a, 0, 0), the radius of the fifth sphere is: c 2 / a; The coordinates of the sixth sphere are: ((a 2 -c 2 ) / 2a, 0, 0), the radius of the sixth sphere is: The coordinates of the seventh sphere are: (-(a 2 -c 2 ) / 2a, 0, 0), the radius of the seventh sphere is: Among them, a is the major semi-axis of the single ellipsoid in the double ellipsoid model, b is the median semi-axis of the single ellipsoid in the double ellipsoid model, and c is the minor semi-axis of the single ellipsoid in the double ellipsoid model.

2. The universal modeling method for wheat grain particles according to claim 1, characterized in that: In the step 2, the size parameters of the double ellipsoid model are: a=0.5L, Among them, a is the major semi-axis of the single ellipsoid in the double ellipsoid model, b is the median semi-axis of the single ellipsoid in the double ellipsoid model, c is the minor semi-axis of the single ellipsoid in the double ellipsoid model, θ is the angle between the double ellipsoids; L is the length of the wheat grain, W is the width of the wheat grain, and T is the thickness of the wheat grain.

3. The universal modeling method for wheat grain particles according to claim 2, characterized in that: The modeling method of the 17-ball combination model is: The 13-sphere combination model is established, and after the eighth sphere and the ninth sphere are filled in the single ellipsoid of the 13-sphere model, a spatial coordinate transformation is performed to obtain the 17-sphere combination model; wherein: The coordinates of the eighth sphere are: The radius of the eighth sphere is The coordinates of the ninth sphere are: The radius of the ninth sphere is 4. The universal modeling method for wheat grain particles according to claim 3, characterized in that: The modeling method of the 25-ball combination model is: The 17-ball combination model is established, and after the tenth to thirteenth balls are filled in the single ellipsoid of the 17-ball model, spatial coordinate transformation is performed to obtain the 25-ball combination model; wherein: The coordinates of the tenth sphere are: The radius of the tenth sphere is The coordinates of the eleventh sphere are: The radius of the eleventh sphere is The coordinates of the twelfth sphere are: The radius of the twelfth sphere is The coordinates of the thirteenth sphere are: The radius of the thirteenth sphere is 5. The universal modeling method for wheat grain particles according to claim 4, characterized in that: The modeling method of the 33-ball combination model is: The 25-sphere combination model is established, and after the fourteenth to seventeenth spheres are filled in the single ellipsoid of the 25-sphere model, spatial coordinate transformation is performed to obtain the 33-sphere combination model; wherein: The coordinates of the fourteenth sphere are: The radius of the fourteenth sphere is The coordinates of the fifteenth sphere are: The radius of the fifteenth sphere is The coordinates of the sixteenth sphere are: The radius of the sixteenth sphere is The coordinates of the seventeenth sphere are: The radius of the seventeenth sphere is 6. The universal modeling method for wheat grain particles according to claim 3, 4 or 5, characterized in that: The spatial coordinate transformation is performed according to the following formula: (x″′y″′z″′1)=(xyz 1)·R(±α); in, Wherein, (xyz 1) is the coordinate before spatial transformation, (x″′y″′z″′1) is the coordinate after spatial transformation, R(±α) is the spatial coordinate transformation matrix; α represents the rotation transformation angle, and its value is θ / 2.

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