A universal modeling method for wheat leaves

Abstract

This invention, applicable to the field of plant modeling and analysis, provides a general wheat leaf modeling method. By selecting leaves from four wheat varieties, the geometric shape and size parameters, as well as their randomness and correlation, are tested and analyzed. Using a sphere-filling arrangement, the coordinates of the particles forming each sphere are solved to obtain a stalk geometric model and four geometric models consisting of three-veined and five-veined spheres arranged in spaced and tangential patterns. The method then measures and calibrates the contact and adhesion parameters between leaves and between leaves and boundaries. These parameters are then added to the mechanical model. The resulting leaf geometric and mechanical models are then input into discrete element software to produce a discrete element model of the wheat leaf. This method provides important data support for modeling wheat leaves and other elongated materials and can be applied to simulation analysis of contact between leaves and agricultural machinery components during wheat harvesting, as well as other technical fields requiring wheat leaf modeling.

Description

Technical Field

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

[0002] Wheat is one of the world's most important food crops, accounting for over 8% of global major crop production over the past 20 years. During each stage of wheat harvesting, such as cutting, threshing, and cleaning, analysis of the interaction between wheat plants and agricultural machinery components remains challenging. Traditional analysis methods currently rely primarily on experiments, which are highly seasonal and costly, hindering the development of mechanized wheat harvesting and precision agriculture. Addressing this challenge requires selecting accurate and efficient simulation analysis methods. Discrete element methods (DEMs), widely used in geotechnical engineering, pharmaceutical and chemical engineering, and agricultural engineering, can intuitively simulate the wheat harvesting process and analyze the mechanical behavior and motion of the plant.

[0003] While modeling methods for wheat plants, including grains and stems, are relatively mature, methods for modeling the leaves are still lacking. This is crucial for studying multi-scale modeling of wheat plants and simulating the contact between plant leaves and agricultural machinery components during wheat harvesting. Summary of the Invention

[0004] The purpose of the embodiments of the present invention is to provide a universal wheat leaf modeling method, aiming to solve the problems raised in the above background technology.

[0005] The embodiment of the present invention is implemented as follows: a universal wheat leaf modeling method comprises the following steps:

[0006] Step 1: Use the component ball particles to assemble a wheat leaf model;

[0007] Step 2: Select several leaves of the four wheat varieties to be modeled, and test and analyze their geometric shape and size parameters as well as their randomness and correlation;

[0008] Step 3: Solve the coordinates of the particles that make up the wheat stalk sphere to obtain the stalk geometric model;

[0009] Step 4: Solve the particle coordinates of the wheat leaf component spheres to obtain four leaf geometric modeling schemes based on the spacing and tangent arrangement of the component spheres with three veins and five veins;

[0010] Step 5: Measure and calibrate the contact mechanical parameters and bonding mechanical parameters of the blade;

[0011] Step 6: Add the above parameters to the corresponding mechanical model. The contact model is the HM-new-restitution model, and the bonding model is the Bonding model.

[0012] Step 7: Input the blade geometric model obtained in step 4 and the mechanical model obtained in step 6 into the discrete element software to obtain the discrete element model of the blade.

[0013] The embodiment of the present invention provides a universal wheat leaf modeling method, which has the following beneficial effects:

[0014] (1) This method is based on the analysis of various dimensional parameters of wheat leaves of the main cultivated varieties in the Huanghuaihai wheat region, the Northwest wheat region, the middle and lower reaches of the Yangtze River wheat region and the Xinjiang wheat region, including Panmai No. 8, Xinong 629, Zhenmai 12, Longmai 67 and Xindong 30. It has certain versatility and is suitable for modeling the leaves of various varieties of wheat.

[0015] (2) The HM-new-restitution model is used as the contact mechanics model between blades to solve the problem of multiple contact points generated during the simulation process, thereby avoiding over-damping and over-rigidity and improving the accuracy of the simulation results. At the same time, the Bonding model is used as the bonding mechanics model to more realistically simulate the bending deformation and fracture of blades under the action of external forces.

[0016] (3) This method is based on the calculation method of normal and tangential forces and torques in the Bonding model. Under the condition of satisfying mechanical properties, it proposes a modeling method in which the component balls can be arranged at a certain interval. Compared with the method in which the component balls are arranged tangentially, it has the advantages of fewer particles and higher simulation efficiency.

[0017] (4) Based on a large number of tests and analyses, the correlations between leaf length and the distance from the leaf tip to the leaf width, stem diameter and leaf bottom width, internode number and leaf width, and internode number and leaf-stem angle were proposed, providing important data support for wheat leaf modeling. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic diagram of wheat leaf model made of component spherical particles;

[0019] Figure 2 This is a schematic diagram of the geometric shape of wheat leaves;

[0020] Figure 3 The arrangement diagram of spherical particles in wheat leaves;

[0021] Figure 4 The correlation between the various shapes and sizes of Fanmai No. 8;

[0022] Figure 5 This is a model diagram of the leaves of the Fanmai No. 8 plant;

[0023] Figure 6 Comparison chart of blade impact test and simulation results;

[0024] Figure 7 A comparison chart of the test and simulation results of a group of leafed plants. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0026] The specific implementation of the present invention is described in detail below with reference to specific embodiments.

[0027] An embodiment of the present invention provides a general wheat leaf modeling method, comprising the following steps:

[0028] Step 1: Use the component ball particles to assemble a wheat leaf model;

[0029] Step 2: Select several leaves of the four wheat varieties to be modeled, and test and analyze their geometric shape and size parameters as well as their randomness and correlation;

[0030] Step 3: Solve the coordinates of the particles that make up the sphere of wheat stalks to obtain the geometric model of the stalks;

[0031] Step 4: Solve the particle coordinates of the wheat leaf component spheres to obtain four leaf geometric modeling schemes based on the spacing and tangent arrangement of the component spheres with three veins and five veins;

[0032] Step 5: Measure and calibrate the contact mechanical parameters and bonding mechanical parameters of the blade;

[0033] Step 6: Add the above parameters to the corresponding mechanical model. The contact model is the HM-new-restitution model, and the bonding model is the Bonding model.

[0034] Step 7: Input the blade geometric model obtained in step 4 and the mechanical model obtained in step 6 into the discrete element software to obtain the discrete element model of the blade.

[0035] In the embodiment of the present invention, the wheat leaf model is formed by splicing the constituent spherical particles as shown in FIG. Figure 1 shown.

[0036] As a preferred embodiment of the present invention, in step 1, the wheat leaf model is divided into stems, flag leaves and other leaves;

[0037] The spherical particles include spherical particles composed of internodes of the stem and spherical particles composed of leaves.

[0038] As a preferred embodiment of the present invention, in step 2, the four wheat varieties are respectively selected from the main cultivated variety Fanmai No. 8 in the Huanghuaihai wheat region, the main cultivated variety Xinong 629 in the Northwest wheat region, the main cultivated variety Xindong 30 in the Xinjiang wheat region, and the main cultivated variety Zhenmai 12 in the middle and lower reaches of the Yangtze River wheat region.

[0039] As a preferred embodiment of the present invention, the wheat plant leaves can be divided into near-root leaves and stem leaves according to their different growth positions. Stem leaves are leaves at the same node as the internode of the stem, and generally grow 5 leaves. Among them, those born on the lower three nodes are called middle leaves, and their photosynthesis supplies stem growth and wheat ear development. Those born on the upper two nodes are called upper leaves (flag leaves and second leaves), and their photosynthesis is mainly used for flowering and fruiting and grain filling, which plays a decisive role in wheat yield. Near-root leaves are clustered leaves born on the tillering nodes. Their function is mainly reflected before the jointing stage. Their photosynthesis also mainly supplies the growth of tillers and roots, and gradually ages and dies during the harvest period. Therefore, when establishing a wheat plant leaf model at the harvest period, it is simplified, and the near-root leaves are ignored. When modeling, the flag leaf, second leaf and 3 middle leaves are included, and the position of each leaf corresponds to the position of each internode from top to bottom.

[0040] As a preferred embodiment of the present invention, except for the flag leaf, which grows upright and is located at a certain distance above the root of the first internode, the tips of the other leaves will droop under the action of gravity, causing the leaves to bend, and the growth position is located at the root of the corresponding internode.

[0041] like Figure 2 and Figure 3 As shown in a preferred embodiment of the present invention, the size parameters of the wheat leaves include the leaf length L leaf , width D leaf , curvature β, bottom width Distance from tip to width of blade Leaf-stem angle α, stem length of each internode L stalk and the stem radius R of each internode stalk , the distance between the flag leaf growth position and the root of the first internode is S.

[0042] like Figure 4As shown, as a preferred embodiment of the present invention, the randomness and correlation between the wheat leaf size parameters include: a strong linear relationship between the leaf length and the distance from the leaf tip to the leaf width, a strong linear relationship between the stem diameter and the bottom width of the leaf, a strong correlation between the leaf width and the cube of the internode number, and a strong correlation between the leaf-stem angle and the cube of the internode number.

[0043] As a preferred embodiment of the present invention, in step 3, for the stem geometric model, the coordinates of the center of the sphere composed of each internode can be expressed as:

[0044]

[0045] in, represents the radius of the component ball of the j-th internode of the stem, which is obtained by taking the average of the measured radius of each internode of the stem; represents the number of bulbs in the jth internode of the stem, which is calculated by the following formula:

[0046]

[0047] in, It represents the length of the j-th internode of the stem, which is obtained by taking the average of the length measurements of each internode of the stem.

[0048] As a preferred embodiment of the present invention, in step 4, for the leaf geometry model, it is assumed that there are three points on the main vein, where Located at the root of the stem internode and connected to the stem, Located on the main vein corresponding to the width of the leaf. Located at the end of the main vein of the leaf, the number of balls of the first main vein of the flag leaf can be expressed as:

[0049]

[0050] in, is the number of balls in the first segment of the main vein, R leaf The radius of the sphere particles that make up the main veins is obtained by averaging the leaf thickness measurements;

[0051] Coordinates of the first point on the main vein of the flag leaf It can be expressed as:

[0052]

[0053] Among them, R leaf represents the radius of the spherical particles that make up the main veins, and α represents the angle between the leaf and stem;

[0054] The coordinates of the second point on the main vein of the flag leaf can be expressed as:

[0055]

[0056] in, Indicates the number of balls composed of the main veins in the first section;

[0057] The coordinates of the third point on the main vein of the flag leaf can be expressed as:

[0058]

[0059] Among them, N leaf Indicates the total number of main leaf veins that make up the bulb.

[0060] As a preferred embodiment of the present invention, for the leaf geometric model, it is assumed that the leaf is located at the jth internode of the stem. and The same position as the upright leaves, because the leaf bending occurs at the leaf width, the leaf bending increases To achieve the bending of the leaf, the coordinates of the first point on the main vein of the remaining leaves can be expressed as:

[0061]

[0062] The coordinates of the second point on the main vein of the remaining leaves can be expressed as:

[0063]

[0064] The coordinates of the third point on the main vein of the remaining leaves can be expressed as:

[0065]

[0066] The coordinates of the fourth point on the main vein of the remaining leaves can be expressed as:

[0067]

[0068] in, β represents the curvature of the blade.

[0069] As a preferred embodiment of the present invention, in the leaf geometric model, the three tangent vein arrangement model includes a main vein and two marginal veins, wherein the two marginal veins are symmetrically distributed on both sides of the main vein, and the x and y coordinates of each component sphere are the same as the x and y coordinates of the main vein, only the z coordinate is different, and the z coordinate is determined by the leaf shape characteristics, that is, the leaf width of the row.

[0070] As a preferred embodiment of the present invention, in the leaf geometric model, the five-vein tangent arrangement model includes a main vein, two edge veins and two intermediate veins, wherein the two intermediate veins are also symmetrically distributed on both sides of the main vein and located between the main vein and the edge veins.

[0071] As a preferred embodiment of the present invention, in the leaf geometric model, each vein of the flag leaf is constructed with leaf shape features by a second-order Bezier curve, and each vein of the remaining leaves is constructed with leaf shape features by a third-order Bezier curve.

[0072] As a preferred embodiment of the present invention, the flag leaf uses a second-order Bezier curve to construct the leaf shape characteristics of the leaf, wherein is the coordinate of any point on the marginal vein of the flag leaf, then the marginal vein of the flag leaf can be expressed as:

[0073]

[0074] Among them, t is a parameter in the Bezier curve, and its value range is between 0 and 1. This parameter can be used to describe the relative position of a point on the curve on the entire curve.

[0075] is the coordinate of any point on the middle vein of the flag leaf, then the middle vein of the flag leaf can be expressed as:

[0076]

[0077] As a preferred embodiment of the present invention, the remaining blades use third-order Bezier curves to construct the blade shape features, where is the coordinate of any point on the marginal veins of the remaining leaves, then the marginal veins of the remaining leaves can be expressed as:

[0078]

[0079] is the coordinate of any point on the middle vein of the leaf, then the middle vein of the leaf can be expressed as:

[0080]

[0081] As a preferred embodiment of the present invention, since the normal and tangential forces and torque in the Bonding model are calculated in an incremental manner, adjacent component balls of the blade can be arranged at a certain interval. In the blade geometric model, the interval arrangement model is based on the three-vein and five-vein tangent arrangement model algorithms. According to the properties of the Bezier curve, the value of t is multiplied by the corresponding multiple to reduce the number of component balls, and obtain a three-vein and five-vein model in which the component balls have a certain interval arrangement.

[0082] As a preferred embodiment of the present invention, in step 5, the contact mechanics parameters of the blade include the static friction coefficient, the rolling friction coefficient and the collision recovery coefficient.

[0083] To ensure the accuracy and reliability of the blade model, the various contact mechanical parameters of the wheat leaves must be measured and calibrated. The static friction coefficients between blades and blades and between blades and boundaries were measured using an inclinometer and a high-speed camera, respectively. The velocities before and after the collision were determined using a high-speed camera using motion analysis software to obtain the coefficients of restitution for blade-to-blade and blade-to-boundary oblique collisions in three-dimensional space. Because wheat leaves are non-spherical particles, the rolling friction coefficient between blades cannot be measured through actual experiments. Therefore, the blade stacking angle test was used to calibrate the blade-to-blade rolling friction coefficient.

[0084] As a preferred embodiment of the present invention, in step 5, the blade bonding mechanical parameters include strength parameters and stiffness parameters.

[0085] Stiffness parameters include normal stiffness per unit area, tangential stiffness per unit area, and bond radius. Because the material properties of the two particles making up the blade are identical, including density, elastic modulus, and Poisson's ratio, the bond model can be simplified to a beam element model. The elastic beam stiffness coefficient is calculated based on the elastic modulus and used as the normal stiffness per unit area and tangential stiffness per unit area in the model parameters. Strength parameters include critical normal stress and critical tangential stress, which can be determined using a texture analyzer through tensile (normal) and shear (tangential) tests.

[0086] As a preferred embodiment of the present invention, this method is used to create a model of five tangentially arranged veins of the leaves of the wheat plant Fanmai No. 8 in the Huanghuaihai wheat region. The constructed model is as follows: Figure 5 The specific steps are as follows:

[0087] 1. Select 30 wheat plants with leaves that are growing normally, and measure the leaf size parameters and stem size parameters of each internode, as shown in Table 1:

[0088] Table 1

[0089]

[0090]

[0091] 2. According to the above measurement results, the randomness and correlation between the various size parameters are analyzed to obtain the blade length L leaf and the distance from the tip to the width of the blade The relationship between them is:

[0092]

[0093] Stem radius R straw and blade bottom width The relationship between them is:

[0094]

[0095] Blade width D leaf and internode number N i The relationship between them is:

[0096] D leaf =24.4708-11.6707N i +3.7323N i 2 -0.3872N i 3

[0097] Leaf-stem angle α and internode number N i The relationship between them is:

[0098] α=40.0695-12.5817N i +8.7146N i 2 -1.2889N i 3

[0099] 3. Solve the particle coordinates of the wheat stalk sphere, as shown in Table 2:

[0100] Table 2

[0101]

[0102]

[0103] 4. Solve the particle coordinates of the wheat leaf sphere, as shown in Table 3:

[0104] Table 3

[0105]

[0106]

[0107]

[0108]

[0109]

[0110]

[0111] 5. Measure and calibrate blade contact mechanical parameters, as shown in Table 4:

[0112] Table 4

[0113]

[0114] 6. Measure and calibrate the blade bonding mechanical parameters, as shown in Table 5:

[0115] Table 5

[0116] Bonding parameters Numerical <![CDATA[Normal stiffness per unit area / N*m -3 > <![CDATA[5.93×10 9 ]]> <![CDATA[Tangential stiffness per unit area / N*m -3 > <![CDATA[1.37×10 9 ]]> Critical normal stress / Pa <![CDATA[4.25×10 8 ]]> Critical tangential stress / Pa <![CDATA[4.95×10 8 ]]> Multiples of t in Bezier curves 3.05

[0117] 7. Input the leaf geometry model and mechanical model into the discrete element software to obtain the discrete element model of the leaf with five alternate veins of Fanmai No. 8, as shown in the figure below. Figure 5 shown.

[0118] Through blade impact tests, the fracture conditions and maximum impact forces of blades under impact loads in tests and simulations were compared to determine the optimal modeling scheme:

[0119] From the experiments and simulations, it can be seen that after the limit stress is reached in the model with three leaf veins arranged at intervals, the particles are in an irregular scattered state, which is quite different from the actual situation; after the limit stress is reached in the model with three leaf veins arranged tangentially, each leaf vein will break from the middle, but due to the large difference in the number and arrangement uniformity of normal and tangential particles, each leaf vein will shrink irregularly after the break, which is quite different from the actual situation; after the limit stress is reached in the model with five leaf veins arranged at intervals, each leaf vein will break from the middle, and the normal and tangential motion states after the break are relatively stable, and there is no leaf vein shrinkage, which is more consistent with the actual situation; after the limit stress is reached in the model with five leaf veins arranged tangentially, each leaf vein will break from the middle, but after the break, the leaf vein will shrink to both ends, which is also inconsistent with the actual situation.

[0120] like Figure 6 As shown in the figure, the maximum impact force of the three-vein model has a large relative error from the actual test, while the maximum impact force of the five-vein model is closer to the actual situation, with an average relative error within 20%. Taking into account the leaf breakage situation, the five-vein interval arrangement is finally determined to be the optimal modeling scheme for Fanmai No. 8.

[0121] The accuracy of the overall model of wheat plants with leaves was verified through a single-strip leaf plant group stacking experiment:

[0122] Comparison of the stacking heights of the three parts in simulation and actual test Figure 7As shown in the figure, the simulation results are usually smaller than the actual test results. The average relative error between the simulation and the actual test of the stacking height at the top of the plant is 5.75%, the relative error in the middle is 9.74%, and the relative error at the bottom is 10.19%, which proves the accuracy of the overall model of the wheat plant with leaves and the general leaf modeling method.

[0123] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A general modeling method for wheat leaves, characterized in that: The following steps are involved: Step 1: Use the component ball particles to assemble a wheat leaf model; Step 2: Select several leaves of the four wheat varieties to be modeled, test and analyze their geometric shapes, and test and analyze the size parameters and their randomness and correlation; Step 3: Solve the coordinates of the particles that make up the wheat stalk sphere to obtain the stalk geometric model; Step 4: Solve the particle coordinates of the wheat leaf component spheres to obtain four leaf geometric modeling schemes based on the spacing and tangent arrangement of the component spheres with three veins and five veins; Step 5: Measure and calibrate the contact mechanical parameters and bonding mechanical parameters of the blade; Step 6: Add the contact mechanics parameters and bonding mechanics parameters to the corresponding mechanical models. The contact model is the HM-new-restitution model, and the bonding model is the Bonding model. Step 7: Input the blade geometric model obtained in step 4 and the mechanical model obtained in step 6 into the discrete element software to obtain the discrete element model of the blade; The geometric shape of the wheat leaf is long lanceolate, and the size parameters include the leaf length L leaf , width D leaf , curvature β, bottom width Distance from tip to width of blade Leaf-stem angle α, stem length of each internode L stalk and the stem radius R of each internode stalk , the distance between the flag leaf growth position and the root of the first internode is S; The randomness and correlation between wheat leaf size parameters include: randomness and correlation analysis between leaf length and distance from leaf tip to leaf width, stem diameter and leaf bottom width, internode number and leaf width, and internode number and leaf-stem angle; In step 3, for the stem geometric model, the coordinates of the center of the sphere composed of each internode are expressed as: in, represents the radius of the component ball of the j-th internode of the stem, which is obtained by taking the average of the measured radius of each internode of the stem; represents the number of bulbs in the jth internode of the stem, which is calculated by the following formula: in, represents the length of the jth internode of the stem, which is obtained by taking the average of the length measurements of each internode of the stem; In step 4, for the leaf geometry model, it is assumed that there are three points on the main vein, where Located at the root of the stem internode and connected to the stem, Located on the main vein corresponding to the width of the leaf. Located at the end of the main vein of the leaf, the number of balls of the first main vein of the flag leaf is expressed as: in, is the number of balls in the first segment of the main vein, R leaf The radius of the sphere particles that make up the main veins is obtained by averaging the leaf thickness measurements; Coordinates of the first point on the main vein of the flag leaf Expressed as: Among them, R leaf represents the radius of the spherical particles that make up the main veins, and α represents the angle between the leaf and stem; The coordinates of the second point on the main vein of the flag leaf are expressed as: in, Indicates the number of balls composed of the main veins of the first segment; The coordinates of the third point on the main vein of the flag leaf are expressed as: Among them, N leaf Indicates the total number of main leaf veins that make up the bulb.

2. The universal wheat leaf modeling method according to claim 1, characterized in that: In step 1, the wheat leaf model is divided into stems, flag leaves and other leaves; The spherical particles include spherical particles composed of internodes of the stem and spherical particles composed of leaves.

3. The universal wheat leaf modeling method according to claim 2, characterized in that: In step 2, the four wheat varieties are Fanmai 8, Xinong 629, Xindong 30, and Zhenmai 12.

4. The universal wheat leaf modeling method according to claim 1, characterized in that: For the leaf geometry model, assuming that the leaf is located at the jth internode of the stem, and The same position as the upright leaves, because the leaf bending occurs at the leaf width, the leaf bending increases To achieve the bending of the leaf, the coordinates of the first point on the main vein of the remaining leaves are expressed as: The coordinates of the second point on the main vein of the remaining leaves are expressed as: The coordinates of the third point on the main vein of the remaining leaves are expressed as: The coordinates of the fourth point on the main vein of the remaining leaves are expressed as: in, β represents the curvature of the blade.

5. The universal wheat leaf modeling method according to claim 4, characterized in that: In the leaf geometry model, the three-vein tangent arrangement model includes a main vein and two marginal veins, wherein the two marginal veins are symmetrically distributed on both sides of the main vein. The x and y coordinates of each component sphere are the same as those of the main vein, and only the z coordinate is different. The z coordinate is determined by the leaf width of the row.

6. The universal wheat leaf modeling method according to claim 5, characterized in that: In the leaf geometric model, the five-vein tangent arrangement model includes a main vein, two marginal veins and two intermediate veins, wherein the two intermediate veins are also symmetrically distributed on both sides of the main vein and located between the main vein and the marginal vein.

7. The universal wheat leaf modeling method according to claim 6, characterized in that: In the leaf geometry model, each leaf vein of the flag leaf is constructed with a second-order Bezier curve to construct the leaf shape feature, where is the coordinate of any point on the marginal vein of the flag leaf, then the marginal vein of the flag leaf is expressed as: Where t is a parameter in the Bezier curve, ranging from 0 to 1, which is used to describe the relative position of a point on the curve. is the coordinate of any point on the middle vein of the flag leaf, then the middle vein of the flag leaf is expressed as: The other leaves use the third-order Bezier curve to construct the leaf shape features. is the coordinate of any point on the marginal veins of the remaining leaves, then the marginal veins of the remaining leaves are expressed as: is the coordinate of any point on the middle vein of the leaf, then the middle vein of the leaf is expressed as:

8. The universal wheat leaf modeling method according to claim 7, characterized in that: The staggered arrangement model is based on the three-vein and five-vein tangent arrangement model algorithms. According to the properties of the Bezier curve, the value of t is multiplied by the corresponding multiple to reduce the number of component balls, and the component balls are obtained with staggered three-vein and five-vein models.

9. The universal wheat leaf modeling method according to claim 8, characterized in that: In step 5, the contact mechanics parameters of the blade include the static friction coefficient, the rolling friction coefficient and the collision restitution coefficient; The blade bonding mechanical parameters include strength parameters and stiffness parameters; among them, the stiffness parameters include normal stiffness per unit area, tangential stiffness per unit area and bonding bond radius; the strength parameters include critical normal stress and critical tangential stress.

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