Effective area prediction method and system based on air spring performance degradation mechanism

Abstract

The invention provides an effective area prediction method and system based on an air spring performance degradation mechanism, and belongs to the technical field of air spring detection, and the method comprises the steps: calculating the effective area radius of an air spring according to the material elastic characteristics of the air spring, the geometric parameters of an air bag, the total thickness of a cord thread layer, and the internal air pressure; multiplying the square of the radius of the effective area by the circumference ratio to obtain a first effective area; multiplying the vertical height of the air spring when the air spring is not loaded by a preset proportionality coefficient to obtain a second effective area; the preset proportionality coefficient is used for reflecting the rule that the effective area of the air spring linearly changes along with the height; and adding the first effective area and the second effective area to obtain a predicted effective area of the air spring. By considering material performance degradation and geometric characteristics, the effective area of the air spring under the dynamic loading condition is accurately calculated, and the accuracy of effective area prediction of the air spring is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of air spring detection, and in particular to an effective area prediction method and system based on an air spring performance degradation mechanism. Background Art

[0002] Air springs are widely used in vehicle suspension systems, and their effective area is an important parameter that directly determines their load-bearing capacity, dynamic performance, and vibration characteristics. However, in long-term use, the cord material and rubber matrix material inside the air spring will degrade due to fatigue loading, resulting in changes in key indicators such as elastic modulus and geometric parameters. This performance degradation will significantly affect the dynamic behavior of the air spring and the change pattern of the effective area. Therefore, accurately predicting the effective area of ​​the air spring is crucial for the design optimization and performance evaluation of the suspension system.

[0003] Existing technologies usually calculate the effective area of ​​air springs based on static geometric analysis or linear mechanical assumptions. These methods can achieve a certain degree of prediction accuracy when the material properties are intact in the initial state. However, when considering the degradation of material properties, the applicability of these methods decreases significantly. Specifically, existing technologies often ignore the dynamic effect of fatigue damage on the elastic modulus of the cord material and the rubber matrix material, and do not fully consider the coupling effect between the airbag geometric properties and the internal air pressure. This simplification makes it difficult for existing calculation methods to accurately reflect the actual working state of the air spring after material degradation, resulting in deviations in the prediction of the effective area. Therefore, how to improve the accuracy of predicting the effective area of ​​air springs has become a technical problem that needs to be solved urgently. Summary of the invention

[0004] The present invention provides an effective area prediction method, system, electronic device and storage medium based on the performance degradation mechanism of an air spring, so as to solve the defects in the prior art and improve the accuracy of the effective area prediction of the air spring.

[0005] The present invention provides an effective area prediction method based on the performance degradation mechanism of an air spring, comprising the following steps: calculating the effective area radius of the air spring according to the material elasticity characteristics of the air spring, the geometric parameters of the airbag, the total thickness of the cord layer and the internal air pressure; wherein the material elasticity characteristics are determined based on the remaining elastic modulus of the cord material and the rubber matrix material after a preset number of fatigue loadings; Multiply the square of the radius of the effective area by pi to obtain the first effective area; The vertical height of the air spring when not loaded is multiplied by a preset proportionality coefficient to obtain a second effective area; the preset proportionality coefficient is used to reflect the law that the effective area of ​​the air spring changes linearly with the height; The first effective area is added to the second effective area to obtain a predicted effective area of ​​the air spring.

[0006] According to the effective area prediction method based on the performance degradation mechanism of the air spring provided by the present invention, the geometric parameters of the airbag include the actual outer wall radius of the airbag after loading, the initial outer wall radius of the airbag when not loaded, and the preset shape coefficient; the effective area radius of the air spring is calculated according to the material elastic properties of the air spring, the geometric parameters of the airbag, the total thickness of the cord layer, and the internal air pressure, specifically including: Calculating a first residual elastic modulus of the cord material after a preset number of fatigue loadings, and a second residual elastic modulus of the rubber matrix material after a preset number of fatigue loadings; Determine a first element and a second element in an inverse matrix of a stiffness matrix of a composite material according to the first residual elastic modulus and the second residual elastic modulus; the first element and the second element are used to reflect elastic response characteristics of the composite material under weft and warp forces; the composite material comprises a cord material and a rubber matrix material; The effective area radius is calculated according to the first element, the second element, the actual outer wall radius, the initial outer wall radius, the preset shape factor, the total thickness of the cord layer, and the internal air pressure.

[0007] According to the effective area prediction method based on the air spring performance degradation mechanism provided by the present invention, the calculation of the first residual elastic modulus of the cord material after a preset number of fatigue loadings and the second residual elastic modulus of the rubber matrix material after a preset number of fatigue loadings specifically includes: Based on the initial elastic modulus of the cord material, combined with the preset fatigue life, the preset material constant and the preset number of times, the first residual elastic modulus is calculated; wherein the first residual elastic modulus decreases according to a predetermined functional relationship as the preset number of times increases, and is used to reflect the fatigue damage degree of the cord material; Based on the initial elastic modulus of the rubber matrix material, combined with a preset fatigue damage coefficient and a preset number of times, the second residual elastic modulus is calculated; wherein the second residual elastic modulus decreases exponentially with an increase in the preset number of times, and is used to reflect the fatigue attenuation characteristics of the rubber matrix material.

[0008] According to the effective area prediction method based on the air spring performance degradation mechanism provided by the present invention, the first element and the second element in the inverse matrix of the stiffness matrix of the composite material are determined according to the first residual elastic modulus and the second residual elastic modulus, specifically including: Calculating a first equivalent elastic modulus of the composite material in a warp direction and a second equivalent elastic modulus of the composite material in a weft direction according to the first residual elastic modulus and the second residual elastic modulus; constructing the stiffness matrix using the first equivalent elastic modulus and the second equivalent elastic modulus; Performing a matrix inversion operation on the stiffness matrix to obtain an inverse matrix of the stiffness matrix; A non-zero element corresponding to a first preset row and column is extracted from the inverse matrix as the first element, and a non-zero element corresponding to a second preset row and column is extracted as the second element.

[0009] According to the effective area prediction method based on the air spring performance degradation mechanism provided by the present invention, the first equivalent elastic modulus of the composite material in the warp direction and the second equivalent elastic modulus of the composite material in the weft direction are calculated according to the first residual elastic modulus and the second residual elastic modulus, specifically including: Determining a first volume fraction of the cord material and a second volume fraction of the rubber matrix material respectively; wherein the sum of the first volume fraction and the second volume fraction is 1; The first equivalent elastic modulus is calculated by multiplying the first volume fraction by the first residual elastic modulus and adding the result of multiplying the second volume fraction by the second residual elastic modulus; The second equivalent elastic modulus is calculated by multiplying the first residual elastic modulus by the second residual elastic modulus and then dividing by a result of multiplying the first volume fraction by the second residual elastic modulus plus a result of multiplying the second volume fraction by the first residual elastic modulus.

[0010] According to the effective area prediction method based on the air spring performance degradation mechanism provided by the present invention, the stiffness matrix is ​​constructed by using the first equivalent elastic modulus and the second equivalent elastic modulus, specifically including: Determine the principal Poisson's ratio of the composite material in the warp direction and the secondary Poisson's ratio of the composite material in the weft direction; Calculate each non-zero element in the stiffness matrix according to the first equivalent elastic modulus, the second equivalent elastic modulus, the primary Poisson's ratio, and the secondary Poisson's ratio; The stiffness matrix is ​​constructed according to all the non-zero elements.

[0011] According to the effective area prediction method based on the air spring performance degradation mechanism provided by the present invention, the effective area radius is calculated according to the first element, the second element, the actual outer wall radius, the initial outer wall radius, the preset shape coefficient, the total thickness of the cord layer and the internal air pressure, specifically including: Subtract the initial outer wall radius from the actual outer wall radius and divide the result by the initial outer wall radius to obtain the latitudinal strain; Based on material mechanics and geometric properties of the air spring, a relationship equation between the latitudinal strain and the effective area radius function is established in combination with the first element, the second element, the total thickness of the cord layer, the internal air pressure, and the actual outer wall radius; wherein the effective area radius function is determined according to the structural properties of the air spring and the preset shape parameters; Solve the relationship equation to obtain the effective area radius.

[0012] The present invention also provides an effective area prediction system based on the air spring performance degradation mechanism, comprising the following modules: A first processing module is used to calculate the effective area radius of the air spring according to the material elasticity characteristics of the air spring, the geometric parameters of the airbag, the total thickness of the cord layer and the internal air pressure; wherein the material elasticity characteristics are determined based on the residual elastic modulus of the rubber matrix material after the cord material and the rubber matrix material are fatigue loaded for a preset number of times; The first processing module is further used to multiply the square of the radius of the effective area by the pi to obtain a first effective area; A second processing module is used to multiply the vertical height of the air spring when it is not loaded by a preset proportionality coefficient to obtain a second effective area; the preset proportionality coefficient is used to reflect the law that the effective area of ​​the air spring changes linearly with the height; The third processing module is used to add the first effective area to the second effective area to obtain a predicted effective area of ​​the air spring.

[0013] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the effective area prediction method based on the air spring performance degradation mechanism as described in any one of the above-mentioned methods is implemented.

[0014] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any of the above-described effective area prediction methods based on the air spring performance degradation mechanism.

[0015] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the effective area prediction method based on the air spring performance degradation mechanism as described in any one of the above is implemented.

[0016] In summary, one or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages: By combining the material elastic properties of the air spring, the geometric parameters of the airbag, the total thickness of the cord layer and the internal air pressure, the effective area radius of the air spring is accurately calculated. The material elastic properties are determined by the residual elastic modulus of the cord material and the rubber matrix material after a preset number of fatigue loadings, which effectively captures the degradation behavior of the material under long-term fatigue loads. This dynamic change is an important basis for predicting the performance of the air spring. The first effective area is obtained by square the calculated effective area radius and multiplying it with pi. This step utilizes the geometric properties of the air spring to quantify the overall load-bearing capacity of the airbag under loading conditions, and intuitively reflects the effective force area of ​​the airbag after the coupling of the material and geometric parameters. At the same time, the vertical height of the air spring when not loaded is multiplied by the preset proportional coefficient to obtain the second effective area. The preset proportional coefficient is determined based on experiments and model analysis, and is used to describe the linear law of the effective area of ​​the air spring with height, ensuring that the geometric parameters fully reflect the calculation of the effective area. By adding the first effective area to the second effective area, the joint influence of material properties, geometric properties and dynamic loading conditions on the effective area of ​​the air spring is comprehensively considered, thereby improving the accuracy of the prediction of the effective area of ​​the air spring. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a flow chart of the effective area prediction method based on the air spring performance degradation mechanism provided by the present invention.

[0019] Figure 2 It is a schematic longitudinal cross-sectional view of the membrane type air spring provided by the present invention.

[0020] Figure 3 It is a cross-section of the air spring provided by the present invention and a schematic diagram of the force of the unit body.

[0021] Figure 4 It is a schematic diagram of force analysis of the airbag micro-element provided by the present invention.

[0022] Figure 5 It is a schematic diagram of the microelement body-following coordinate system and main direction definition provided by the present invention.

[0023] Figure 6 It is a schematic diagram of the anti-symmetrical laying of four layers of airbags provided by the present invention.

[0024] Figure 7It is a schematic diagram of the air spring performance degradation test process provided by the present invention.

[0025] Figure 8 It is a schematic diagram of the relationship between the characteristic parameters of the rubber airbag provided by the present invention and the change of the cord inclination angle.

[0026] Fig. 9 It is a schematic diagram of the change law of the effective area of ​​the air spring provided by the present invention after the performance is degraded.

[0027] Fig.10 It is a schematic diagram of the change law of the effective area of ​​the air spring under different fatigue times and excitation amplitudes provided by the present invention.

[0028] Fig.11 It is a schematic diagram of the effect of the cord Young's modulus provided by the present invention on the change of the effective area of ​​the air spring.

[0029] Fig.12 It is a schematic diagram of the effect of the Young's modulus of rubber on the change of the effective area of ​​the air spring provided by the present invention.

[0030] Fig.13 It is a structural schematic diagram of the effective area prediction system based on the air spring performance degradation mechanism provided by the present invention.

[0031] Fig.14 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] It should be noted that, in the description of the present invention, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "include one..." do not exclude the existence of other identical elements in the process, method, article or device including the elements. The orientation or positional relationship indicated by the terms "upper", "lower", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the system or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0034] The terms "first", "second", etc. in the present invention are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present invention can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally of the same type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" means at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0035] Combine the following Figure 1-Figure 14 The present invention describes an effective area prediction method, system, electronic device and storage medium based on the air spring performance degradation mechanism.

[0036] Figure 1 is a flow chart of the effective area prediction method based on the air spring performance degradation mechanism provided by the present invention, such as Figure 1 As shown, steps 101-104 are included: Step 101: Calculate the effective area radius of the air spring based on the material elastic properties of the air spring, the geometric parameters of the airbag, the total thickness of the cord layer and the internal air pressure; wherein the material elastic properties are determined based on the remaining elastic modulus of the cord material and the rubber matrix material after a preset number of fatigue loadings.

[0037] During the long-term use of air springs, the performance of the cord material and rubber matrix material will gradually degrade with the accumulation of fatigue loading. This degradation directly leads to a decrease in the elastic modulus of the material and has a significant impact on the dynamic performance and effective area of ​​the air spring. Therefore, in order to accurately predict the effective area of ​​the air spring, it is first necessary to calculate the effective area radius of the air spring based on the elastic properties of the material, the geometric parameters of the airbag, the total thickness of the cord layer, and the internal air pressure, taking into full account the changes in the characteristics of the material under different fatigue loading conditions.

[0038] In a possible implementation, the geometric parameters of the airbag include an actual outer wall radius of the airbag after loading, an initial outer wall radius of the airbag when not loaded, and a preset shape coefficient; step 101 specifically includes steps 201-203: Step 201: Calculate a first residual elastic modulus of the cord material after a preset number of fatigue loadings, and a second residual elastic modulus of the rubber matrix material after a preset number of fatigue loadings.

[0039] In order to accurately calculate the effective area radius of the air spring, the fatigue damage degree of the cord material and the rubber matrix material must first be quantified, that is, their first residual elastic modulus and second residual elastic modulus after a preset number of fatigue loadings are calculated respectively.

[0040] The first residual elastic modulus of the cord material is used to describe the retention of the elastic properties of the material after fatigue loading. Its degradation is mainly affected by the initial elastic modulus of the material, the preset fatigue life, the material constant and the number of loadings. By combining these factors, the gradual decrease of the elastic modulus of the cord material can be described by a predetermined functional relationship, which can accurately characterize the accumulation law of the degree of fatigue damage.

[0041] The second residual elastic modulus of the rubber matrix material is calculated using an exponential decay model. During the loading process, the internal microcracks of the rubber material gradually expand and the molecular chains break. The accumulation of these microscopic damages directly leads to an exponential decrease in the elastic modulus of the rubber matrix material. Based on the initial elastic modulus of the material, the preset fatigue damage coefficient, and the number of loadings, the fatigue decay characteristics of the rubber matrix material can be accurately characterized.

[0042] In a possible implementation, step 201 specifically includes steps 301-302: Step 301: Based on the initial elastic modulus of the cord material, combined with a preset fatigue life, a preset material constant and a preset number of times, a first residual elastic modulus is calculated; wherein the first residual elastic modulus decreases according to a predetermined functional relationship as the preset number of times increases, and is used to reflect the degree of fatigue damage of the cord material.

[0043] The cord material is the core load-bearing part of the air spring, and its initial elastic modulus It determines the mechanical properties of the material under normal working conditions. However, as the air spring is subjected to fatigue loading in long-term operation, its elastic modulus gradually decreases, showing typical fatigue damage accumulation characteristics. In order to accurately calculate the first residual elastic modulus of the cord material after fatigue loading, , need to be based on , preset fatigue life , preset number N and preset material constant m to establish a corresponding mathematical model.

[0044] Specifically, the first residual elastic modulus of the cord material Calculate according to the following formula: ; This formula is based on the continuum damage mechanics model by introducing the damage variable Describes the elastic modulus degradation characteristics of the cord material under different preset times N, where is defined as: ; In the above model, the fatigue life is preset It indicates the maximum number of loads that the cord material can withstand, and the preset material constant m reflects the degradation rate of the cord material during fatigue loading. For typical steel cord materials, m is usually taken as 3 to accurately describe its nonlinear degradation behavior.

[0045] This calculation process can intuitively reflect the fatigue damage characteristics of the cord material. When the damage variable The value of is small, and the residual elastic modulus of the cord material is close to the initial elastic modulus. However, as N increases, the damage variable The residual elastic modulus of the cord material increases rapidly, and the residual elastic modulus of the cord material shows a significant downward trend. Through this model, the complex fatigue damage process can be mathematically quantified, and the performance changes of the cord material at different fatigue stages can be quantified.

[0046] Step 302: Based on the initial elastic modulus of the rubber matrix material, combined with a preset fatigue damage coefficient and a preset number of times, a second residual elastic modulus is calculated; wherein the second residual elastic modulus decreases exponentially with an increase in the preset number of times, so as to reflect the fatigue attenuation characteristics of the rubber matrix material.

[0047] The rubber matrix material is a key component of the air spring. Its initial elastic modulus It determines the flexible response ability of the material in the undegraded state. However, the rubber matrix material will experience significant performance degradation under long-term fatigue loading, which is manifested as a gradual decrease in the elastic modulus with the increase in the number of loading times. This attenuation is mainly caused by the breakage of rubber molecular chains, the expansion of microcracks, and the accumulation of internal damage in the material. In order to accurately characterize this dynamic degradation process, it is necessary to use a model to calculate the second residual elastic modulus of the rubber matrix material after a preset number of fatigue loadings. .

[0048] The elastic modulus decay of rubber matrix materials is usually described by an exponential decay model. The specific calculation formula is: ; Where b is a preset fatigue damage coefficient related to the rubber matrix material and loading conditions, which is used to reflect the rate at which the elastic modulus of the rubber matrix material decays with the preset number N. This formula accurately describes the fatigue characteristics of the rubber matrix material through exponential decay, especially the performance changes under high load and long-term loading conditions.

[0049] Specifically, when the loading times are small, the molecular structure of the rubber matrix material is still relatively intact, and the internal damage accumulation is limited, so the elastic modulus The rate of decline is slow. As the number of loading times increases, the microcracks inside the material begin to expand significantly, the molecular chain breaks gradually accumulate, and the damage effect accelerates, causing the elastic modulus to decline rapidly in an exponential manner. This attenuation characteristic clearly reflects the nonlinear effect of the number of loading times on the performance of the rubber matrix material through the formula.

[0050] The calculation method of this exponential decay model can not only quantitatively describe the performance degradation of the rubber matrix material at different fatigue loading stages, but also combine the initial elastic modulus of the material The preset fatigue damage coefficient b can be quickly adjusted to adapt to different material properties, thereby improving the universality and adaptability of the model.

[0051] Step 202: Determine the first element and the second element in the inverse matrix of the stiffness matrix of the composite material according to the first residual elastic modulus and the second residual elastic modulus; the first element and the second element are used to reflect the elastic response characteristics of the composite material under latitudinal and longitudinal forces; the composite material includes a cord material and a rubber matrix material.

[0052] In the performance prediction of air springs, the elastic response characteristics of composite materials have a key influence on the calculation of the effective area radius. Composite materials are composed of cord materials and rubber matrix materials. Their elastic response characteristics in the warp and weft directions are affected by the elastic modulus, volume fraction and loading conditions of the two materials. Therefore, in order to accurately predict the effective area radius of air springs, the first and second elements in the inverse matrix of the composite stiffness matrix must be determined based on the first residual elastic modulus and the second residual elastic modulus. These elements are used to quantitatively describe the elastic response characteristics of the composite materials in different directions.

[0053] In a possible implementation, step 202 specifically includes steps 401-404: Step 401: Calculate a first equivalent elastic modulus of the composite material in the warp direction and a second equivalent elastic modulus of the composite material in the weft direction according to the first residual elastic modulus and the second residual elastic modulus.

[0054] The first equivalent elastic modulus of the composite material in the warp direction and the second equivalent elastic modulus in the latitudinal direction are the core parameters that describe the mechanical properties of air spring materials. They directly reflect the comprehensive elastic properties of the cord material and the rubber matrix material in different directions, and provide key inputs for the construction of the composite material stiffness matrix and the accurate prediction of air spring performance. and It is a necessary step to predict the effective area of ​​the air spring.

[0055] In a possible implementation, step 401 specifically includes steps 501-503: Step 501: respectively determining a first volume fraction of the cord material and a second volume fraction of the rubber matrix material; wherein the sum of the first volume fraction and the second volume fraction is 1.

[0056] In composite materials, the volume fractions of cord materials and rubber matrix materials directly determine their contribution ratios to the overall elastic properties of the material. Therefore, in order to calculate the equivalent elastic modulus of the composite material in the warp and weft directions, the first volume fraction of the cord material must be determined. and the second volume fraction of the rubber matrix material Through these two parameters, the proportion of the two materials in the composite material can be quantified to ensure the physical meaning and accuracy of subsequent calculations.

[0057] The volume fraction needs to be determined based on the design parameters of the air spring (such as the cord layer's density, thickness, and coverage ratio of the rubber matrix) and material properties. It represents the proportion of the cord in the total volume of the composite material, while the second volume fraction of the rubber matrix material The remaining part is used to describe the proportion of the rubber matrix material in the composite material. This definition ensures that the sum of the first volume fraction and the second volume fraction is 1, reflecting the consistency of the overall volume of the material.

[0058] Step 502: Calculate a first equivalent elastic modulus by multiplying the first volume fraction by the first residual elastic modulus and adding the result of multiplying the second volume fraction by the second residual elastic modulus.

[0059] Specifically, according to the aforementioned embodiment, the first equivalent elastic modulus It can be expressed by the following formula: ; The cord material has a higher elastic modulus and mainly bears the tensile load in the warp direction, while the elastic modulus of the rubber matrix material is relatively low, but it can effectively share the load through its flexibility. Therefore, weighting the elastic moduli of the two materials according to the volume fraction can accurately describe the overall load-bearing capacity of the composite material in the warp direction.

[0060] Step 503: Calculate a second equivalent elastic modulus by multiplying the first residual elastic modulus by the second residual elastic modulus and then dividing the result by multiplying the first volume fraction by the second residual elastic modulus plus the result by multiplying the second volume fraction by the first residual elastic modulus.

[0061] Specifically, according to the aforementioned embodiment, the second equivalent elastic modulus It can be expressed by the following formula: ; This calculation method fully considers the significant difference between the elastic modulus of the cord material and the rubber matrix material, and reflects their action characteristics in different force directions. Due to the low elastic modulus of the rubber matrix material, its dominant role in the weft direction is significantly enhanced, while the cord material has a high elastic modulus, but its distribution and directionality have limited contribution to the weft response. By means of harmonic averaging, the characteristics of the two materials are reasonably combined to obtain a more realistic weft elastic modulus.

[0062] Step 402: construct a stiffness matrix using the first equivalent elastic modulus and the second equivalent elastic modulus.

[0063] The construction of the composite material stiffness matrix is ​​a key link in the prediction model of the effective area of ​​the air spring. Its purpose is to accurately characterize the elastic response characteristics of the composite material in the warp and weft directions, as well as the mechanical behavior of the cord material and the rubber matrix material under the joint action of the composite material. The stiffness matrix, as a bridge connecting the elastic modulus of the material and the geometric parameters of the air spring, is the core foundation for subsequent inverse matrix operations and effective area radius calculations. Therefore, it is necessary to construct the stiffness matrix based on accurate physical parameters and mechanical formulas.

[0064] In a possible implementation, step 402 specifically includes steps 601-603: Step 601: Determine a principal Poisson's ratio of the composite material in the warp direction and a secondary Poisson's ratio of the composite material in the weft direction.

[0065] Step 602: Calculate each non-zero element in the stiffness matrix according to the first equivalent elastic modulus, the second equivalent elastic modulus, the primary Poisson's ratio, and the secondary Poisson's ratio.

[0066] Step 603: Construct a stiffness matrix based on all non-zero elements.

[0067] The stiffness matrix of the composite material is the core tool to describe the mechanical properties of the air spring material in the warp, weft and shear directions. In order to construct the stiffness matrix of the composite material, it is first necessary to determine the principal Poisson's ratio of the composite material in the warp direction. and the secondary Poisson's ratio in the latitudinal direction , and based on the composite material mechanics theory, the eccentric reduced stiffness matrix is ​​simplified to calculate the key non-zero elements. This can accurately characterize the mechanical properties of composite materials and simplify the calculation complexity.

[0068] In the theory of composite material mechanics, the principal Poisson's ratio It is a known parameter, usually determined by composite material design or experiment. It is calculated by the following relationship: ; This relationship ensures symmetry and consistency in material mechanics, in this way reducing the need for independent calculations of Poisson's ratio while ensuring harmony between physical parameters.

[0069] In order to further construct the stiffness matrix of the composite material, based on the characteristics of the eccentric reduced stiffness matrix, some elements in the matrix can be simplified. The formula given by the composite material mechanics theory is as follows: ; in, is the cord laying angle, which indicates the angle between the cord direction and the warp direction in the composite material; , , and are the stiffness parameters of the composite material in the warp, weft and shear directions respectively. Due to the symmetry of the composite material and the particularity of the fiber direction, some items in the matrix can be obtained by simplified calculation. For example, when For a specific laying angle (such as 45 ∘ ), some trigonometric function terms can be directly calculated as constant values, thus reducing the computational complexity.

[0070] Next, according to the formula: ; Calculate the non-zero elements in the matrix respectively. Here G12G_{12}G12 is the shear modulus of the composite material, which can be determined by experiment or material design parameters.

[0071] After completing the above calculations, the final stiffness matrix is ​​constructed through all non-zero elements This process not only reduces unnecessary calculations, but also ensures the physical meaning and accuracy of the stiffness matrix. Ultimately, the constructed stiffness matrix can fully describe the mechanical properties of the composite material in the warp, weft and shear directions, providing accurate input data for the subsequent inverse matrix solution.

[0072] Step 403: Perform a matrix inversion operation on the stiffness matrix to obtain an inverse matrix of the stiffness matrix.

[0073] Stiffness matrix The row matrix inversion operation is . First, calculate the determinant (the matrix's determinant): ; Next, calculate the adjoint matrix (swap the diagonal elements and negate the off-diagonal elements): ; Finally, the inverse of the stiffness matrix is: .

[0074] Step 404: extracting non-zero elements corresponding to the first preset row and column from the inverse matrix as first elements, and extracting non-zero elements corresponding to the second preset row and column as second elements.

[0075] According to the mechanical property requirements of the composite material, the first element and the second element are extracted from the non-zero elements in the first row and the first column and the first row and the second column of the inverse matrix, respectively. These elements reflect the elastic response of the composite material under the action of latitudinal stretching and longitudinal and latitudinal coupling.

[0076] In concrete form, the first element and the second element The formula is: ; This operation allows to extract elastic parameters directly related to the calculation of the effective area of ​​the air spring from the comprehensive description of the stiffness matrix. and , which provides the necessary input for establishing the relationship equation between latitudinal strain and effective area radius in the subsequent steps. This method not only improves the physical fit of the calculation, but also ensures the accuracy of the prediction model and the applicability of actual engineering, solving the problem of difficulty in quantifying the directional elastic response of composite materials in the existing technology.

[0077] Step 203: Calculate the effective area radius according to the first element, the second element, the actual outer wall radius, the initial outer wall radius, the preset shape coefficient, the total thickness of the cord layer, and the internal air pressure.

[0078] The effective area radius of an air spring directly affects its load-bearing capacity and dynamic performance, and is an important parameter for predicting the performance of an air spring. In the case of material performance degradation, accurate calculation of the effective area radius is the key to ensuring that the prediction results are close to the actual working conditions. Therefore, it is necessary to combine the elastic response characteristics of the composite material, the geometric parameters of the air spring, the total thickness of the cord layer, and the internal air pressure to establish the relationship between the latitudinal strain and the effective area radius, so as to accurately derive the effective area radius.

[0079] In a possible implementation, step 203 specifically includes steps 701-703: Step 701: Subtract the initial outer wall radius from the actual outer wall radius and divide the result by the initial outer wall radius to obtain the latitudinal strain.

[0080] The latitudinal strain is the core parameter that describes the material and geometric deformation characteristics of the air spring under loading conditions. Its calculation directly affects the prediction accuracy of the effective area radius. In actual work, the actual outer wall radius of the air spring after loading is and the initial outer wall radius when unloaded It is a key geometric parameter that can be directly measured or designed. Calculating the latitudinal strain through these geometric parameters can not only accurately quantify the radial deformation of the air spring, but also provide a basis for the subsequent establishment of the relationship between the latitudinal strain and the effective area radius.

[0081] Specifically, the latitudinal strain The calculation formula is: ; The molecule in the formula The radial deformation of the outer wall of the airbag before and after loading is quantified. The deformation is normalized to reflect the ratio of the deformation degree to the initial state of the airbag. This normalized calculation method makes the definition of latitudinal strain universal and physically meaningful, and can be applied to air springs of different sizes and designs.

[0082] By calculating the latitudinal strain, the geometric deformation characteristics of the air spring can be converted into parameters related to the mechanical properties of the material. Especially under loading conditions, the latitudinal strain directly reflects the strain coupling effect of the cord material and the rubber matrix material in the composite material in different directions, and is an important bridge connecting geometric parameters and material properties. This parameterization process greatly simplifies the complex material-geometry coupling relationship, making the subsequent calculation of the effective area radius more intuitive and easy to operate.

[0083] Step 702: Based on material mechanics and the geometric properties of the air spring, combined with the first element, the second element, the total thickness of the cord layer, the internal air pressure, and the actual outer wall radius, a relationship equation between the latitudinal strain and the effective area radius function is established; wherein the effective area radius function is determined according to the structural characteristics and preset shape parameters of the air spring.

[0084] The relationship between the latitudinal strain and the effective area radius directly reflects the mechanical behavior of the air spring under the conditions of material performance degradation and geometric deformation. In order to accurately calculate the effective area radius, it is necessary to establish a relationship equation between the latitudinal strain, the total thickness of the cord layer, the internal air pressure, and the key parameters in the inverse matrix of the composite material stiffness matrix based on the material mechanics theory and the geometric characteristics of the air spring. This relationship equation can quantify the material and structural changes under actual working conditions and ensure the physical fit of the model.

[0085] The specific construction rules of the effective area radius function are as follows: Generally speaking, the cross-section of the membrane air spring for passenger cars is circular, and its longitudinal section is as follows Figure 2 As shown, Figure 2 is a schematic longitudinal cross-sectional view of a membrane type air spring provided by the present invention, wherein: is the actual outer wall radius, is the effective area radius. Since there are curling and bending at the connection with the upper and lower cover plates and the piston, the middle straight line segment of the airbag away from the upper and lower end surfaces is selected for force analysis.

[0086] After selecting the cross section Figure 3 As shown, Figure 3 It is a schematic diagram of the cross section of the air spring and the force of the unit body provided by the present invention. Assume that the entire cross section is subjected to a vertical tensile force P and the tensile force is proportional to the gas pressure according to the different shapes of the airbag contours ( is the shape parameter): ; Vertical height after , unit center angle The corresponding airbag microelement is subjected to stress analysis. It is mainly subjected to gas pressure and vertical tension. Airbag tension Effect, ignoring the gravity of the airbag, the force equation can be obtained as follows: ; Reference Figure 4 , Figure 4 Schematic diagram of force analysis of the airbag microelement provided by the present invention. F 2 direction) and latitude (d F 1 direction) for stress analysis, we can get: ; Since this application focuses on studying the variation of the effective area of ​​air springs under different performance degradation degrees and different amplitudes A. In the above formula, the internal pressure will change with different amplitudes, and according to the ideal gas state equation, it can be obtained: ; After reorganizing the above formula, we can get: ; in, is the vertical height of the air spring when it is not loaded, the subscript 0 represents the initial state, and K is the height correction coefficient. Further Taylor expansion near the equilibrium position yields: ; in, is atmospheric pressure. Since the thickness of the airbag is small compared to the outer wall radius, the airbag is approximately considered as a plane stress state in this paper. The cylindrical coordinate system is converted to a rectangular coordinate system, which satisfies the basic assumptions of composite material mechanics theory and can be used for subsequent analysis. The air spring airbag cord layer can be regarded as a composite laminate, which is mainly composed of anti-symmetrically laid composite single-layer plates. n s is an even number. The matrix of the laminate is rubber, assuming that the generalized elastic modulus of rubber satisfies the relationship: ; in, , are the equivalent volume and shear moduli of rubber materials respectively. Now take a single-layer plate to explain the body coordinate system and define the main directions, such as Figure 5 As shown, Figure 5 It is a schematic diagram of the microelement body-following coordinate system and main direction definition provided by the present invention.

[0087] As mentioned above, air spring airbags are mostly laid in an anti-symmetrical manner, that is, the cord angle is mostly [+α c / … / - α c / + α c / … / - α c The air spring selected in this paper is laid in four layers. n s =4, see the laying diagram Figure 6 , Figure 6 It is a schematic diagram of the anti-symmetric laying of the four layers of the airbag provided by the present invention. According to basic composite material mechanics, the tensile stiffness matrix A and the coupling stiffness matrix B of the anti-symmetric laminate have constant zero terms and tension-torsion coupling. The internal force vector of the laminate can be expressed as: ; According to the characteristics of antisymmetric laminates, for two single-layer plates with opposite angles, we have: ; Ignoring the twist rate of the laminate, let , then the total thickness of the cord layer can be obtained The formula for the external force on the airbag per unit length and width is as follows: ; Thus we can get: ; in, is the equivalent radius.

[0088] According to the above formula, the strain formula of the mid-surface in the body coordinate system can be obtained: ; Here we are mainly concerned with the mid-surface in the latitude direction ( x The strain in the direction) is used to calculate the effective area radius. It is the initial radius when the radial deformation of the airbag is not obvious as the internal pressure increases, which is measured by actual test. According to the above formula and the macro-geometric definition of air spring airbag strain, it can be obtained: ; It can be deduced that: ; Substitution Then, the relationship equation of the effective area radius function is derived: .

[0089] Step 703: Solve the relationship equation to obtain the effective area radius.

[0090] The effective area radius is obtained by solving the key equation, and the effective area radius is expressed by the following formula: .

[0091] Step 102: Multiply the square of the radius of the effective area by pi to obtain a first effective area.

[0092] The first effective area can be expressed by the following formula: .

[0093] Step 103: Multiply the vertical height of the air spring when it is not loaded by a preset proportionality coefficient to obtain a second effective area; the preset proportionality coefficient is used to reflect the rule that the effective area of ​​the air spring changes linearly with the height.

[0094] Specifically, the preset scale factor It is based on the results of a large number of experiments and geometric analysis. First, the initial height of the air spring when it is not loaded is obtained by measuring or designing parameters. Then, the appropriate proportional coefficient is selected or fitted based on the experimental data, reflecting the law that the effective area of ​​the air spring changes linearly with the height. The experimental results show that when unloaded, the effective area of ​​the air spring is mainly determined by the height change of the airbag, and its change trend can be accurately described by linear fitting. Therefore, the preset proportional coefficient With vertical height Multiply to calculate the second effective area: .

[0095] Step 104: Add the first effective area and the second effective area to obtain the predicted effective area of ​​the air spring.

[0096] In the above steps, the first effective area It has been calculated by multiplying the square of the effective area radius by pi, reflecting the comprehensive material and geometric response of the airbag under loading conditions; the second effective area It is calculated by multiplying the vertical height of the air spring when it is not loaded by the preset proportional coefficient, which mainly reflects the influence of the change in geometric height. In order to fully predict the effective area of ​​the air spring, these two parts need to be added together to obtain the total predicted effective area.

[0097] Therefore, the predicted effective area of ​​the air spring can be expressed by the following formula: .

[0098] Furthermore, the predicted effective area of ​​the air spring of the present application is verified. Figure 7 , Figure 7The figure is a schematic diagram of the performance degradation test flow of the air spring provided by the present invention. The experiment aims to perform a performance degradation test on the air spring using a fatigue temperature chamber and an MTS dynamometer (850 Damper Test System) to evaluate its performance degradation under different fatigue cycles. First, the MTS dynamometer is used to apply a vertical vibration load to the air spring so that the air spring works in a balanced position. Then, the load amplitude is A =1;2;5;10;20mm, frequency is f =0.01;0.1;0.5;1;2;5Hz dynamometer test and record the transmission force and displacement. Each amplitude is loaded with the corresponding frequency. Three dynamometer cycles are performed for each working condition and the last cycle data is taken as the test result. Then the air spring is placed in a variable temperature fatigue chamber for fatigue loading at different temperatures (-30; 65; 80℃ respectively). The total number of fatigue tests is N =180;360;450 million times of tests, and after each fatigue test, the MTS equipment was used to collect air spring dynamometer tests under the same working conditions and obtain test data. High temperature will accelerate the aging of the cord and rubber matrix, resulting in a decrease in fatigue life. In a high temperature environment, the stiffness of the material decreases faster and the accumulation of fatigue damage is more obvious.

[0099] Reference Figure 8 , Figure 8 Schematic diagram of the relationship between the characteristic parameters of the rubber airbag provided by the present invention and the inclination angle of the cord. It can be seen that Q 1 As the cord inclination increases (90 degrees represents vertical arrangement), it shows a trend of first increasing and then slowly decreasing; and when the air spring is subjected to fatigue loading (this application selects N = 5 million times), according to the above theory, Q 1 will increase when the cord angle is large, resulting in a change in the effective area of ​​the final air spring; Q 2 With the increase of the cord angle, it shows a trend of first decreasing and then increasing. Q The effect of 2 is not significant.

[0100] After clarifying the material parameters and the influence of different fatigue times on them, the change of the effective area of ​​the air spring under different fatigue times can be calculated. Fig. 9 , Fig. 9It is a schematic diagram of the change law of the effective area of ​​the air spring after the performance degradation provided by the present invention. It can be seen that under the same fatigue times, the effective area of ​​the air spring increases with the increase of the excitation amplitude, and as the fatigue times increase, the effective area of ​​the air spring will increase with the increase of the fatigue times. From a physical point of view, since the Young's modulus of the rubber airbag cord and the rubber material have both decreased, but since the cord is the main supporting carrier, its Young's modulus decreases, resulting in a decrease in the bearing capacity of the rubber airbag, so the effective area increases under the same working conditions. It can be seen that the theory proposed in this application is highly consistent with the experimental test results, and the prediction error of the effective area of ​​the air spring under different performance degradation degrees is less than 1%.

[0101] After verifying the correctness of the theory of this application, refer to Fig.10 , Fig.10 It is a schematic diagram of the change law of the effective area of ​​the air spring under different fatigue times and excitation amplitudes provided by the present invention. It can be seen that under the same fatigue loading times, as the amplitude increases, the increase in the effective area of ​​the air spring shows an accelerating trend, and under large fatigue loading, the influence of different amplitudes on the effective area will gradually weaken. In a physical sense, this is because the difference in the degree of degradation of the performance of the cord and the rubber material under large fatigue loading will cause the degree of mechanical properties of the rubber airbag to decrease, so the degree of change of the effective area will also decrease. Under the same amplitude, as the performance of the air spring continues to degrade, the effective area will gradually increase, but different amplitudes have different effects on the rate of change.

[0102] After analyzing the different degrees of performance degradation of air springs and the influence of different excitation amplitudes on their effective areas from a mechanism perspective, in order to further give the influence of different design parameters on the performance degradation of air springs, this application selects two most intuitive design parameters for comparison, namely the cord of the rubber airbag and the Young's modulus of the rubber material, referring to Fig.11 and Fig.12 , Fig.11 Schematic diagram of the effect of the Young's modulus of the cord on the change of the effective area of ​​the air spring provided by the present invention, Fig.12 It is a schematic diagram of the effect of the Young's modulus of rubber on the change of the effective area of ​​the air spring provided by the present invention.

[0103] It can be seen that with the increase of the Young's modulus of the cord, the curve of the relationship between the effective area of ​​the air spring and the number of fatigue times will move downward. From the perspective of physical mechanism, under the same cord degradation model, the lower the Young's modulus of the cord, the weaker the rubber airbag's ability to resist deformation, which in turn leads to an increase in the effective area. However, from the trend point of view, when the Young's modulus increases to infinity, the entire rubber airbag can be regarded as a rigid body, and its effective area will not change regardless of whether it is degraded, which is consistent with the predicted results. Similarly, the increase in the Young's modulus of the rubber will cause the curve cluster to decrease. The principle is consistent with the change of the cord, but its impact is more severe than that of the cord.

[0104] The effect of other parameters on the change of effective area of ​​air spring after performance degradation can be calculated through the theory proposed in this application. This application focuses on the change of effective area of ​​air spring under different degrees of performance degradation under dynamic conditions, filling the gaps in existing research. The calculation method of the predicted effective area of ​​air spring proposed in this application can provide theoretical support for the positive design and risk prevention of air springs.

[0105] Reference Fig.13 , Fig.13 : is a structural schematic diagram of an effective area prediction system based on the air spring performance degradation mechanism provided by the present invention, the system comprising: The first processing module is used to calculate the effective area radius of the air spring according to the material elasticity characteristics of the air spring, the geometric parameters of the airbag, the total thickness of the cord layer and the internal air pressure; wherein the material elasticity characteristics are determined based on the residual elastic modulus of the cord material and the rubber matrix material after a preset number of fatigue loadings; The first processing module is further used to multiply the square of the radius of the effective area by the pi to obtain a first effective area; A second processing module is used to multiply the vertical height of the air spring when it is not loaded by a preset proportionality coefficient to obtain a second effective area; the preset proportionality coefficient is used to reflect the law that the effective area of ​​the air spring changes linearly with the height; The third processing module is used to add the first effective area and the second effective area to obtain the predicted effective area of ​​the air spring.

[0106] In a possible implementation manner, the first processing module is further configured to: Calculating a first residual elastic modulus of the cord material after a preset number of fatigue loadings, and a second residual elastic modulus of the rubber matrix material after a preset number of fatigue loadings; Determine the first element and the second element in the inverse matrix of the stiffness matrix of the composite material according to the first residual elastic modulus and the second residual elastic modulus; the first element and the second element are used to reflect the elastic response characteristics of the composite material under the weft and warp forces; the composite material includes a cord material and a rubber matrix material; The effective area radius is calculated according to the first element, the second element, the actual outer wall radius, the initial outer wall radius, the preset shape factor, the total thickness of the cord layer, and the internal air pressure.

[0107] In a possible implementation manner, the first processing module is further configured to: Based on the initial elastic modulus of the cord material, combined with the preset fatigue life, the preset material constant and the preset number of times, a first residual elastic modulus is calculated; wherein the first residual elastic modulus decreases according to a predetermined functional relationship as the preset number of times increases, and is used to reflect the fatigue damage degree of the cord material; Based on the initial elastic modulus of the rubber matrix material, combined with the preset fatigue damage coefficient and the preset number of times, the second residual elastic modulus is calculated; wherein the second residual elastic modulus decreases exponentially with the increase of the preset number of times, which is used to reflect the fatigue attenuation characteristics of the rubber matrix material.

[0108] In a possible implementation manner, the first processing module is further configured to: Calculating a first equivalent elastic modulus of the composite material in a warp direction and a second equivalent elastic modulus of the composite material in a weft direction according to the first residual elastic modulus and the second residual elastic modulus; Using the first equivalent elastic modulus and the second equivalent elastic modulus, a stiffness matrix is ​​constructed; Perform matrix inversion operation on the stiffness matrix to obtain the inverse matrix of the stiffness matrix; The non-zero elements corresponding to the first preset rows and columns are extracted from the inverse matrix as the first elements, and the non-zero elements corresponding to the second preset rows and columns are extracted as the second elements.

[0109] In a possible implementation manner, the first processing module is further configured to: Determining a first volume fraction of the cord material and a second volume fraction of the rubber matrix material respectively; wherein the sum of the first volume fraction and the second volume fraction is 1; The first equivalent elastic modulus is calculated by multiplying the first volume fraction by the first residual elastic modulus and adding the result of multiplying the second volume fraction by the second residual elastic modulus; The second equivalent elastic modulus is calculated by multiplying the first residual elastic modulus by the second residual elastic modulus and then dividing by the result of multiplying the first volume fraction by the second residual elastic modulus plus the result of multiplying the second volume fraction by the first residual elastic modulus.

[0110] In a possible implementation manner, the first processing module is further configured to: Determine the principal Poisson's ratio of the composite material in the warp direction and the secondary Poisson's ratio of the composite material in the weft direction; Calculate each non-zero element in the stiffness matrix according to the first equivalent elastic modulus, the second equivalent elastic modulus, the primary Poisson's ratio, and the secondary Poisson's ratio; Construct the stiffness matrix based on all non-zero elements.

[0111] In a possible implementation manner, the first processing module is further configured to: Subtract the initial outer wall radius from the actual outer wall radius and divide it by the initial outer wall radius to obtain the latitudinal strain; Based on material mechanics and geometric properties of the air spring, the relationship equation between the latitudinal strain and the effective area radius function is established by combining the first element, the second element, the total thickness of the cord layer, the internal air pressure, and the actual outer wall radius; wherein the effective area radius function is determined according to the structural characteristics and preset shape parameters of the air spring; Solve the relationship equation to obtain the effective area radius.

[0112] It should be noted that the effective area prediction system based on the air spring performance degradation mechanism provided by the present invention can execute the effective area prediction method based on the air spring performance degradation mechanism of any of the above embodiments during specific operation, which will not be elaborated in this embodiment.

[0113] Fig.14 is a schematic diagram of the structure of the electronic device provided by the present invention, such as Fig.14 As shown, the electronic device may include: a processor 1410 (processor), a communication interface 1420 (CommunicationsInterface), a memory 1430 (memory) and a communication bus 1440 , wherein the processor 1410 , the communication interface 1420 , and the memory 1430 communicate with each other through the communication bus 1440 . Processor 1410 can call logic instructions in memory 1430 to execute an effective area prediction method based on the performance degradation mechanism of an air spring, the method comprising: calculating the effective area radius of the air spring according to the material elastic properties of the air spring, the geometric parameters of the airbag, the total thickness of the cord layer, and the internal air pressure; wherein the material elastic properties are determined based on the remaining elastic modulus of the cord material and the rubber matrix material after a preset number of fatigue loadings; multiplying the square of the effective area radius by the pi to obtain a first effective area; multiplying the vertical height of the air spring when unloaded by a preset proportional coefficient to obtain a second effective area; the preset proportional coefficient is used to reflect the law that the effective area of ​​the air spring changes linearly with height; adding the first effective area to the second effective area to obtain the predicted effective area of ​​the air spring.

[0114] In addition, the logic instructions in the above-mentioned memory 1430 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0115] On the other hand, the present invention also provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium, and the computer program includes program instructions. When the program instructions are executed by a computer, the computer can execute the effective area prediction method based on the air spring performance degradation mechanism provided in the above-mentioned embodiments, the method including: calculating the effective area radius of the air spring according to the material elastic properties of the air spring, the geometric parameters of the airbag, the total thickness of the cord layer and the internal air pressure; wherein the material elastic properties are determined based on the remaining elastic modulus of the cord material and the rubber matrix material after a preset number of fatigue loadings; multiplying the square of the effective area radius by pi to obtain a first effective area; multiplying the vertical height of the air spring when unloaded by a preset proportional coefficient to obtain a second effective area; the preset proportional coefficient is used to reflect the law that the effective area of ​​the air spring changes linearly with the height; adding the first effective area to the second effective area to obtain the predicted effective area of ​​the air spring.

[0116] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by the processor 1410, is implemented to execute the effective area prediction method based on the air spring performance degradation mechanism provided in the above-mentioned embodiments, the method comprising: calculating the effective area radius of the air spring according to the material elastic properties of the air spring, the geometric parameters of the airbag, the total thickness of the cord layer and the internal air pressure; wherein the material elastic properties are determined based on the remaining elastic modulus of the cord material and the rubber matrix material after a preset number of fatigue loadings; multiplying the square of the effective area radius by pi to obtain a first effective area; multiplying the vertical height of the air spring when unloaded by a preset proportional coefficient to obtain a second effective area; the preset proportional coefficient is used to reflect the law that the effective area of ​​the air spring changes linearly with the height; adding the first effective area to the second effective area to obtain the predicted effective area of ​​the air spring.

[0117] The system embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, i.e., they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Those of ordinary skill in the art may understand and implement it without creative effort.

[0118] Through the description of the above implementation modes, those skilled in the art can clearly understand that each implementation mode can be implemented by means of software plus a necessary general hardware platform, or of course by hardware. Based on such an understanding, the above technical solution can essentially or in other words be embodied in the form of a software product that contributes to the prior art. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods of each embodiment or some parts of the embodiment.

[0119] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for predicting the effective area based on the performance degradation mechanism of an air spring, characterized in that: include: The effective area radius of the air spring is calculated according to the material elasticity characteristics of the air spring, the geometric parameters of the airbag, the total thickness of the cord layer and the internal air pressure; wherein the material elasticity characteristics are determined based on the residual elastic modulus of the cord material and the rubber matrix material after a preset number of fatigue loadings; Multiply the square of the radius of the effective area by pi to obtain the first effective area; The vertical height of the air spring when not loaded is multiplied by a preset proportionality coefficient to obtain a second effective area; the preset proportionality coefficient is used to reflect the law that the effective area of ​​the air spring changes linearly with the height; The first effective area is added to the second effective area to obtain a predicted effective area of ​​the air spring.

2. The effective area prediction method based on the air spring performance degradation mechanism according to claim 1 is characterized in that: The geometric parameters of the airbag include the actual outer wall radius of the airbag after loading, the initial outer wall radius of the airbag when not loaded, and a preset shape coefficient; the effective area radius of the air spring is calculated according to the material elastic properties of the air spring, the geometric parameters of the airbag, the total thickness of the cord layer, and the internal air pressure, specifically including: Calculating a first residual elastic modulus of the cord material after a preset number of fatigue loadings, and a second residual elastic modulus of the rubber matrix material after a preset number of fatigue loadings; Determine a first element and a second element in an inverse matrix of a stiffness matrix of a composite material according to the first residual elastic modulus and the second residual elastic modulus; the first element and the second element are used to reflect elastic response characteristics of the composite material under weft and warp forces; the composite material comprises a cord material and a rubber matrix material; The effective area radius is calculated according to the first element, the second element, the actual outer wall radius, the initial outer wall radius, the preset shape factor, the total thickness of the cord layer, and the internal air pressure.

3. The effective area prediction method based on the air spring performance degradation mechanism according to claim 2 is characterized in that: The calculating of the first residual elastic modulus of the cord material after a preset number of fatigue loadings and the second residual elastic modulus of the rubber matrix material after a preset number of fatigue loadings specifically includes: Based on the initial elastic modulus of the cord material, combined with the preset fatigue life, the preset material constant and the preset number of times, the first residual elastic modulus is calculated; wherein the first residual elastic modulus decreases according to a predetermined functional relationship as the preset number of times increases, and is used to reflect the fatigue damage degree of the cord material; Based on the initial elastic modulus of the rubber matrix material, combined with a preset fatigue damage coefficient and a preset number of times, the second residual elastic modulus is calculated; wherein the second residual elastic modulus decreases exponentially with an increase in the preset number of times, and is used to reflect the fatigue attenuation characteristics of the rubber matrix material.

4. The effective area prediction method based on the air spring performance degradation mechanism according to claim 2 is characterized in that: The determining, according to the first residual elastic modulus and the second residual elastic modulus, the first element and the second element in the inverse matrix of the stiffness matrix of the composite material specifically includes: Calculating a first equivalent elastic modulus of the composite material in a warp direction and a second equivalent elastic modulus of the composite material in a weft direction according to the first residual elastic modulus and the second residual elastic modulus; constructing the stiffness matrix using the first equivalent elastic modulus and the second equivalent elastic modulus; Performing a matrix inversion operation on the stiffness matrix to obtain an inverse matrix of the stiffness matrix; A non-zero element corresponding to a first preset row and column is extracted from the inverse matrix as the first element, and a non-zero element corresponding to a second preset row and column is extracted as the second element.

5. The effective area prediction method based on the air spring performance degradation mechanism according to claim 4 is characterized in that: The step of calculating a first equivalent elastic modulus of the composite material in the warp direction and a second equivalent elastic modulus of the composite material in the weft direction according to the first residual elastic modulus and the second residual elastic modulus specifically includes: Determining a first volume fraction of the cord material and a second volume fraction of the rubber matrix material respectively; wherein the sum of the first volume fraction and the second volume fraction is 1; The first equivalent elastic modulus is calculated by multiplying the first volume fraction by the first residual elastic modulus and adding the result of multiplying the second volume fraction by the second residual elastic modulus; The second equivalent elastic modulus is calculated by multiplying the first residual elastic modulus by the second residual elastic modulus and then dividing by a result of multiplying the first volume fraction by the second residual elastic modulus plus a result of multiplying the second volume fraction by the first residual elastic modulus.

6. The effective area prediction method based on the air spring performance degradation mechanism according to claim 4 is characterized in that: The step of constructing the stiffness matrix by using the first equivalent elastic modulus and the second equivalent elastic modulus specifically includes: Determine the principal Poisson's ratio of the composite material in the warp direction and the secondary Poisson's ratio of the composite material in the weft direction; Calculate each non-zero element in the stiffness matrix according to the first equivalent elastic modulus, the second equivalent elastic modulus, the primary Poisson's ratio, and the secondary Poisson's ratio; The stiffness matrix is ​​constructed according to all the non-zero elements.

7. The effective area prediction method based on the air spring performance degradation mechanism according to claim 2 is characterized in that: The calculating the effective area radius according to the first element, the second element, the actual outer wall radius, the initial outer wall radius, the preset shape factor, the total thickness of the cord layer and the internal air pressure specifically includes: Subtract the initial outer wall radius from the actual outer wall radius and divide the result by the initial outer wall radius to obtain the latitudinal strain; Based on material mechanics and geometric properties of the air spring, a relationship equation between the latitudinal strain and the effective area radius function is established in combination with the first element, the second element, the total thickness of the cord layer, the internal air pressure, and the actual outer wall radius; wherein the effective area radius function is determined according to the structural properties of the air spring and the preset shape parameters; Solve the relationship equation to obtain the effective area radius.

8. An effective area prediction system based on the air spring performance degradation mechanism, characterized in that: include: A first processing module is used to calculate the effective area radius of the air spring according to the material elasticity characteristics of the air spring, the geometric parameters of the airbag, the total thickness of the cord layer and the internal air pressure; wherein the material elasticity characteristics are determined based on the remaining elastic modulus of the cord material and the rubber matrix material after a preset number of fatigue loadings; The first processing module is further used to multiply the square of the radius of the effective area by the pi to obtain a first effective area; A second processing module is used to multiply the vertical height of the air spring when it is not loaded by a preset proportionality coefficient to obtain a second effective area; the preset proportionality coefficient is used to reflect the law that the effective area of ​​the air spring changes linearly with the height; The third processing module is used to add the first effective area to the second effective area to obtain a predicted effective area of ​​the air spring.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that: When the processor executes the computer program, the effective area prediction method based on the air spring performance degradation mechanism as described in any one of claims 1 to 7 is implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the effective area prediction method based on the air spring performance degradation mechanism as described in any one of claims 1 to 7 is implemented.

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