Air spring performance degradation analysis method, device and equipment based on structural characteristics

Abstract

The invention provides an air spring performance degradation prediction method, device and equipment based on structural characteristics, and relates to the technical field of air springs. The method comprises the following steps: acquiring dynamic stiffness and structural parameters of a to-be-evaluated air spring; inputting the dynamic stiffness and the structural parameters into an air spring performance degradation model to obtain fatigue loading parameters output by the air spring performance degradation model; wherein the air spring performance degradation model is a pre-constructed model about the mathematical relationship between the fatigue loading parameter of the air spring and the dynamic stiffness of the air spring; and determining the fatigue life of the to-be-evaluated air spring based on the fatigue loading parameter. According to the method, the fatigue characteristic of the air spring can be pre-estimated according to the actual application scene of the vehicle in the initial stage of vehicle design, so that the stable and reliable air spring can be designed, the product reliability is improved, the development period can be shortened, an enterprise does not need to design the air spring through many tests, and the development cost is saved.

Description

Technical Field

[0001] The present invention relates to the technical field of air springs, and in particular to a method, device and equipment for analyzing performance degradation of an air spring based on structural characteristics. Background Art

[0002] The air suspension system is an important chassis subsystem of the vehicle, which is related to the ride comfort of the vehicle. It plays the role of bearing the weight of the vehicle body and attenuating the vibration transmitted from the road surface to the vehicle body. The advantages of the air suspension system are due to its elastic element - the air spring. Unlike traditional coil springs or leaf springs, air springs use the high-pressure air in the airbag as the medium for transmitting force, have a wide load adaptation range, and are currently being promoted and applied to automobiles and rail vehicles.

[0003] The fatigue life of air springs is related to the safety performance, reliability performance and riding comfort of passengers of vehicles. In recent years, research on the performance degradation of air springs / air suspensions has gradually emerged. For example, some analytical studies have shown that the factors that affect the fatigue life of air springs include air spring design factors, chassis design factors, etc. However, these analytical studies only give qualitative conclusions and do not give specific quantitative analysis rules for air spring fatigue models. There is a lack of accurate quantitative analysis models to provide theoretical support for the design and material selection of air springs. Summary of the invention

[0004] The present invention provides an air spring performance degradation analysis method, device and equipment based on structural characteristics, which are used to solve the defect of lacking an accurate air spring performance degradation analysis model in the prior art and realize accurate calculation of the fatigue life of the air spring according to a mathematical model.

[0005] The present invention provides an air spring performance degradation analysis method based on structural characteristics, comprising the following steps: Obtain the dynamic stiffness and structural parameters of the air spring to be evaluated; Inputting the dynamic stiffness and the structural parameter into an air spring performance degradation model to obtain a fatigue loading parameter output by the air spring performance degradation model; wherein the air spring performance degradation model is a pre-constructed model of the mathematical relationship between the fatigue loading parameter of the air spring and the dynamic stiffness of the air spring; Based on the fatigue loading parameter, the fatigue life of the air spring to be evaluated is determined.

[0006] According to a method for analyzing performance degradation of an air spring based on structural characteristics provided by the present invention, the fatigue life of the air spring to be evaluated is determined based on the fatigue loading parameter, including: Comparing the fatigue parameter with a pre-constructed fatigue life mapping relationship table to obtain the fatigue life matching the fatigue parameter; The pre-constructed fatigue life mapping relationship table is used to characterize the mapping relationship between dynamic stiffnesses of different sizes and fatigue loading parameters of different sizes.

[0007] According to a method for analyzing air spring performance degradation based on structural characteristics provided by the present invention, the step of obtaining the dynamic stiffness and structural parameters of the air spring to be evaluated includes: Using a frequency response analyzer to collect the dynamic stiffness of the air spring to be evaluated; The structural parameters of the air spring to be evaluated are collected.

[0008] According to a method for analyzing air spring performance degradation based on structural characteristics provided by the present invention, the air spring performance degradation model is: ; (1) ; (2) ; (3) ; (4) ; (5) in, is the dynamic stiffness of the air spring, is the excitation frequency, is the effective area of ​​the air spring, is the effective area of ​​the air spring Stiffness due to vertical displacement changes; It is the stiffness generated by the high pressure gas inside the air bag; It is the equivalent damping generated by the heat exchange between the high-pressure gas inside the air bag and the outside world; Indicates the pressure inside the air spring body volume; is the initial pressure of the gas inside the air spring; Indicates the atmospheric pressure of the external environment; is the gas polyvariability index; is the initial airbag volume of the airbag; is the specific heat at constant volume; is the initial gas mass in the air bag; is the equivalent heat transfer coefficient; is the additional stiffness caused by the drop ear bending moment; N is the number of fatigue loading; is the effective radius of the air spring; It is the thickness of the internal reinforcement composite material between the inner and outer rubber layers in the airbag structure; is the volume fraction of the cord; is the initial Young's modulus of the cord; c is the correction factor for the number of fatigue loading times N; is the cord inclination angle; is the Young's modulus of the airbag rubber material of the air spring at zero strain; is the Young's modulus of the airbag rubber material under infinite strain; b is the hardening coefficient related to the rubber material and loading conditions; It is the total fatigue life of the rubber material, which is usually measured by test or specified manually; is the piston inclination angle; A is the excitation amplitude, is the characteristic amplitude of the rubber airbag; is the total thickness of the airbag; The thickness of the reinforced composite material layer inside the airbag layer is; is an empirical parameter related to the fractal dimension of rubber.

[0009] According to a method for analyzing air spring performance degradation based on structural characteristics provided by the present invention, the method of collecting the dynamic stiffness of the air spring to be evaluated by using a frequency response analyzer comprises: The dynamic stiffness of the air spring to be evaluated is obtained by analyzing the air spring hysteresis curve.

[0010] According to a method for analyzing air spring performance degradation based on structural characteristics provided by the present invention, the air spring to be evaluated is a membrane air spring.

[0011] The present invention also provides an air spring performance degradation analysis device based on structural characteristics, comprising the following modules: A parameter acquisition module, used to obtain the dynamic stiffness and structural parameters of the air spring to be evaluated; a fatigue loading parameter calculation module, used for inputting the dynamic stiffness and the structural parameter into an air spring performance degradation model to obtain a fatigue loading parameter output by the air spring performance degradation model; wherein the air spring performance degradation model is a pre-constructed model of the mathematical relationship between the fatigue loading parameter of the air spring and the dynamic stiffness of the air spring; The fatigue life determination module is used to determine the fatigue life of the air spring to be evaluated based on the fatigue loading parameter.

[0012] 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 computer program, the air spring performance degradation analysis method based on structural characteristics as described above is implemented.

[0013] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, and when the computer program is executed by a processor, the air spring performance degradation analysis method based on structural characteristics as described in any one of the above is implemented.

[0014] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the air spring performance degradation analysis method based on structural characteristics as described above is implemented.

[0015] The air spring performance degradation analysis method, device and equipment based on structural characteristics provided by the present invention obtain the dynamic stiffness and structural parameters of the air spring to be evaluated; input the dynamic stiffness and structural parameters into the air spring performance degradation model to obtain the fatigue loading parameters output by the air spring performance degradation model; wherein the air spring performance degradation model is a pre-constructed model of the mathematical relationship between the fatigue loading parameters of the air spring and the dynamic stiffness of the air spring; based on the fatigue loading parameters, the fatigue life of the air spring to be evaluated is determined. This method can pre-estimate the fatigue characteristics of the air spring according to the actual application scenarios of the vehicle in the early stage of vehicle design, thereby helping to design a stable and reliable air spring, improve product reliability, and shorten the development cycle, so that enterprises do not need to undergo many experiments to design air springs, saving development costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] 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.

[0017] Figure 1 It is a structural schematic diagram of the membrane type air spring provided by the present invention.

[0018] Figure 2 It is a flow chart of the air spring performance degradation analysis method based on structural characteristics provided by the present invention.

[0019] Figure 3 It is a schematic diagram of model parameters of the air spring provided by the present invention.

[0020] Figure 4 It is a schematic cross-sectional view of an airbag of an air spring provided by the present invention.

[0021] Figure 5 It is a schematic diagram of the airbag structure and layer height of the air spring provided by the present invention.

[0022] Figure 6It is a schematic diagram of the hysteresis curve of the air spring provided by the present invention.

[0023] Figure 7 It is a schematic structural diagram of an air spring performance degradation analysis device based on structural characteristics provided by the present invention.

[0024] Figure 8 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0025] 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.

[0026] Combine the following Figure 1-Figure 8 Specific embodiments of the present invention are described.

[0027] First, let's briefly introduce the structure of the air spring. Air springs can be divided into single-chamber air springs and air springs with additional air chambers. Among them, single-chamber air springs have two main structural forms, namely, capsule air springs and membrane air springs. This application takes membrane air springs as the research object and explains the performance degradation analysis method of membrane air springs.

[0028] like Figure 1 As shown, Figure 1 The schematic diagram of the structure of the model air spring is that the membrane air spring includes an upper cover plate, an airbag and a piston with a certain arc profile shape. By designing the curvature of the outer contour curve of the piston, different stiffness characteristics can be designed.

[0029] Figure 1 FIG. 1 is a flow chart of the air spring performance degradation analysis method based on structural characteristics provided by the present invention, such as Figure 2 As shown, the method includes the following: Step 201, obtaining the dynamic stiffness and structural parameters of the air spring to be evaluated; The air spring to be evaluated refers to the air spring whose fatigue life needs to be evaluated. The dynamic stiffness of an air spring refers to the ratio of the deformation of the air spring when it is subjected to an external load to the rate of change of the load. The dynamic stiffness reflects the ability of the air spring to resist deformation under the action of dynamic load and is an important indicator of the dynamic characteristics of the air spring. The dynamic stiffness is related to the rubber material of the air spring, the structure of the air spring, the internal gas pressure and the excitation frequency.

[0030] Structural parameters include: effective radius of air spring , Total thickness of airbag , the thickness of the internal reinforcement composite material between the inner and outer rubber layers in the airbag structure , piston inclination , cord inclination , cord volume fraction wait.

[0031] Specifically, the dynamic stiffness of the air spring to be evaluated can be measured, for example, by applying different static loads to the air spring, measuring the relationship between its deformation and force, and then calculating the dynamic stiffness value. It is also possible to use professional equipment such as a frequency response analyzer to stimulate the air spring with an excitation signal of a certain frequency, and calculate the dynamic stiffness value by measuring its vibration response. The above structural parameters can be obtained through measurement.

[0032] Step 202, inputting the dynamic stiffness and the structural parameter into an air spring performance degradation model to obtain a fatigue loading parameter output by the air spring performance degradation model; wherein the air spring performance degradation model is a pre-constructed model of a mathematical relationship between the fatigue loading parameter of the air spring and the dynamic stiffness of the air spring; Among them, the air spring performance degradation model is a pre-constructed model of the mathematical relationship between the fatigue loading parameters of the air spring and the dynamic stiffness of the air spring, as follows: ; (1) ; (2) ; (3) ; (4) ; (5) in, is the dynamic stiffness of the air spring, is the excitation frequency, is the effective area of ​​the air spring, is the effective area of ​​the air spring Stiffness due to vertical displacement changes; It is the stiffness generated by the high pressure gas inside the air bag; It is the equivalent damping generated by the heat exchange between the high-pressure gas inside the air bag and the outside world; Indicates the pressure inside the air spring body volume; is the initial pressure of the gas inside the air spring; Indicates the atmospheric pressure of the external environment; is the gas polytropic index, which depends on the speed of spring deformation. It is 1.0 for isothermal process in static state and close to 1.4 for adiabatic process in dynamic state. is the initial airbag volume of the airbag; is the specific heat at constant volume; is the initial gas mass in the air bag; is the equivalent heat transfer coefficient; is the additional stiffness caused by the drop ear bending moment; N is the number of fatigue loading; is the effective radius of the air spring; It is the thickness of the internal reinforcement composite material between the inner and outer rubber layers in the airbag structure; is the volume fraction of the cord; is the initial Young's modulus of the cord; c is the correction factor for the number of fatigue loading times N; is the cord inclination angle; is the Young's modulus of the airbag rubber material of the air spring at zero strain; is the Young's modulus of the airbag rubber material under infinite strain; b is the hardening coefficient related to the rubber material and loading conditions; It is the total fatigue life of the rubber material, which is usually measured by test or specified manually; is the piston inclination angle; A is the excitation amplitude, is the characteristic amplitude of the rubber airbag; is the total thickness of the airbag; The thickness of the reinforced composite material layer inside the airbag layer is; It is an empirical parameter related to the fractal dimension of rubber and is determined by experiments.

[0033] Specifically, the dynamic stiffness of the air spring to be evaluated obtained by the above measurement is The structural parameters of the air spring to be evaluated are input into the above model, and the fatigue loading parameter N (ie, the number of fatigue loading times) of the air spring to be evaluated can be calculated.

[0034] The theoretical derivation process of the model is as follows: First, if Figure 3 As shown, Figure 3 is a parameter diagram of the air spring. Figure 3 middle, is the gas temperature inside the air spring bag, is the gas mass inside the air spring airbag. According to existing research, the frequency correlation model of the dynamic characteristics of the air spring is: ; (6) ; (7) ; (8) ; (9) in, is the dynamic stiffness generated by the gas in the air spring, is the excitation frequency, is the effective area of ​​the air spring The stiffness resulting from the change of displacement in the z direction; It is the stiffness generated by the high pressure gas inside the air bag; It is the equivalent damping generated by the heat exchange between the high-pressure gas inside the air bag and the outside world; Indicates the pressure inside the air spring body volume; is the initial pressure of the gas inside the air spring; Indicates the atmospheric pressure of the external environment; is the gas polytropic index, which depends on the speed of spring deformation. It is 1.0 for isothermal process in static state and close to 1.4 for adiabatic process in dynamic state. is the initial airbag volume of the airbag; is the specific heat at constant volume; is the initial gas mass in the air bag; is the equivalent heat transfer coefficient; is the effective area of ​​the air spring The rate of change of displacement in the z direction, where the z direction is the vertical direction.

[0035] Storage modulus of the airbag structure of the membrane air spring The relationship between the excitation amplitude A is: ; (10) in, is the Young's modulus of the airbag rubber material of the air spring at zero strain, is the Young's modulus of the airbag rubber material under infinite strain, A is the excitation amplitude, is the characteristic amplitude of the rubber airbag; It is an empirical parameter related to the fractal dimension of rubber and is determined by experiments.

[0036] Since the rubber material and cord material of the air conditioner spring will change in Young's modulus when the performance is degraded, this application is based on the rubber airbag structure, uses composite material theory and performance degradation theory to explain the physical mechanism of the device, and conducts experimental verification.

[0037] First, under different times of fatigue loading, the Young's modulus of the cord and rubber material inside the air spring rubber airbag usually changes. It is generally believed that as fatigue loading continues, the elastic modulus of the cord (also known as Young's modulus) will gradually decrease. This decrease indicates that the load-bearing capacity of the cord is weakened, resulting in the cord being unable to effectively support the rubber layer when the airbag inflates, making the air spring more susceptible to deformation under the same load.

[0038] According to the fatigue damage accumulation theory, the material will gradually accumulate microscopic damage during fatigue loading, including the formation of microcracks, fiber breakage, and the expansion of internal defects in the material. As the number of fatigue loading times N increases, these damages will continue to accumulate, resulting in a decrease in the mechanical properties of the material, especially a decrease in Young's modulus.

[0039] This application uses a continuous damage mechanics model based on damage variables to describe material degradation during fatigue. This model characterizes the degradation of materials under fatigue loading by defining damage variables. The change with damage (i.e. fatigue loading times N) can be expressed as: ; (11) in, is the initial Young's modulus of the cord; N is the number of fatigue loading; c is the correction coefficient for the number of fatigue loading N.

[0040] For rubber materials, rubber composite materials will experience fatigue hardening under high-frequency and long-term fatigue loading, that is, the stiffness of the material gradually increases within a specific fatigue stage. This phenomenon is caused by the further orientation of the molecular chain structure of the rubber after high stress and repeated loading.

[0041] This application normalizes the number of loading times N to facilitate the representation of the accelerated hardening of the material during the entire fatigue process. It is assumed that the Young's modulus of the airbag rubber material is The fatigue loading times N vary as follows: ; (12) in, is the initial Young's modulus of the rubber material; N is the number of fatigue loading; is the total fatigue life of the rubber material (i.e. the limit value of the fatigue loading times), which is used to reflect the rate at which Young's modulus changes with the fatigue loading times; a is the growth exponent of accelerated growth; b is the hardening coefficient related to the rubber material and loading conditions, which is used to describe the degree of hardening of the material.

[0042] Next, based on the airbag structure design, the relationship between dynamic stiffness and performance degradation law is established. This application assumes that the dynamic stiffness generated by the airbag is mainly composed of the drop ear bending moment. Figure 4 Schematic diagram of the cross section of the airbag.

[0043] like Figure 4 As shown, the internal bending moment (vertical to the cross section) at the angle θ of the ear section airbag is , the vertical tension on the airbag is P, the radius of the ear is r, and the piston inclination angle is , is the equivalent Young's modulus (the Young's modulus of all materials in the entire airbag layer). Using the principle of minimum complementary energy, the internal bending moment due to the drooping ear can be derived The additional displacement The expression is: ; (13) in, It is the moment of inertia of the cross section along the bending direction at the lug, which is generated by the interaction of the cord and the rubber material; is the equivalent Young's modulus; is the bending stiffness; is the internal bending moment of the airbag at the angle θ of the drop ear section; P is the vertical tension on the airbag; r is the radius of the drop ear; is the piston inclination angle; θ is the angle between the vertical line and the hanging ear bending moment. In addition, Figure 4 middle, It represents the tangential force on the drooping ear; It is the vertical force transmitted by the air spring.

[0044] When calculating the stiffness of the drop ear caused by bending moment, it is necessary to clearly define the bending stiffness From the design structure of the air spring, we can know that in the rubber airbag structure, the inner and outer sides are rubber layers, which play a protective role; the middle is a cord-rubber reinforced composite material layer, which mainly plays a role in stabilizing the structure and providing tensile stiffness, so the cross-section bending stiffness cannot be analyzed simply by material mechanics. Figure 5 The schematic diagram of the airbag structure and cord layer is shown. Assume that the total thickness of the airbag is The thickness of the reinforced composite material layer inside the airbag layer is ; According to the definition of cross-sectional bending stiffness EI (where E is the elastic modulus of the material, and I is the moment of inertia of the cross section about the neutral axis, which is related to the shape and size of the cross section), combined with the physical meaning and actual situation, the influence of Poisson's ratio on displacement and elastic modulus is ignored here, and the expression of cross-sectional bending stiffness can be obtained based on elastic mechanics as follows: ; (14) in, is the bending stiffness, is the elastic modulus of the airbag rubber material, is the moment of inertia about the central axis in the interface; is the Young's modulus along the central axis of the air spring; z is the air spring stroke; A is the excitation amplitude; is the effective radius of the air spring; is the volume fraction of the cord; is the initial Young's modulus of the cord; N is the number of fatigue loading; c is the correction coefficient for the number of fatigue loading N; is the cord inclination angle; is the Young's modulus of the airbag rubber material of the air spring at zero strain; b is the hardening coefficient related to the rubber material and loading conditions; is the total fatigue life of the rubber material; The growth exponent for accelerating growth is an empirical parameter and is a constant; is the total thickness of the airbag; It is the thickness of the reinforced composite material layer inside the airbag layer.

[0045] Substituting equation (14) into equation (13), we can obtain the additional stiffness caused by the ear bending moment of the airbag: By further integrating the piston inclination angle, we can get the expression of dynamic stiffness generated by the rubber airbag. The expression comprehensively considers the structural design, performance degradation characterization, material and structural parameters of the airbag, and can accurately characterize the contribution of the airbag to the dynamic stiffness in addition to the gas stiffness (that is, the additional stiffness generated by the drooping ear bending moment of the airbag). Some parameters in the formula can be directly measured, and some parameters need to be determined through experiments.

[0046] ; (15) in, is the additional stiffness generated by the droop bending moment of the airbag; P is the vertical tension on the airbag; is the internal bending moment due to the hanging ear The additional displacement generated (see formula (13)); is the effective radius; The thickness of the composite material layer reinforced inside the airbag layer; is the volume fraction of the cord; is the Young's modulus of the cord during performance degradation; is the cord inclination angle; is the Young's modulus of the airbag rubber material of the air spring at zero strain; is the Young's modulus of the airbag rubber material under infinite strain; A is the excitation amplitude; is the characteristic amplitude (which can be measured experimentally); It is an empirical parameter related to the fractal dimension of rubber and is determined by experiments; is the total thickness of the rubber airbag; r is the radius of the hanging ear; is the piston inclination angle; is the initial Young's modulus of the cord; c is the correction factor for the number of fatigue loading N; N is the number of fatigue loading; b is the hardening coefficient related to the rubber material and loading conditions; is the total fatigue life of the rubber material.

[0047] This formula can be used to calculate the dynamic stiffness contributed by the airbag in the early stages of manufacturing and testing.

[0048] In summary, the dynamic stiffness of the membrane air spring at low amplitude should be composed of the dynamic stiffness generated by the gas and the dynamic stiffness generated by the rubber airbag. Based on the actual design, the two should be in parallel in structure. Therefore, combined with the dynamic stiffness expressions (6)-(9) generated by the gas, the overall dynamic stiffness expression of the membrane air spring can be obtained as follows: ; (16) in, is the additional stiffness caused by the droop bending moment of the airbag; is the effective area of ​​the air spring Stiffness due to vertical displacement changes; is the stiffness generated by the high pressure gas inside the air bag; It is the equivalent damping generated by the heat exchange between the high-pressure gas inside the air bag and the outside world; is the excitation frequency; is the overall dynamic stiffness of the membrane air spring.

[0049] From a structural point of view, the storage modulus generated by the airbag can be equivalent to a spring element, but the effect of the loss modulus cannot be equivalent to damping. This is because it is only a function of the excitation amplitude and has nothing to do with frequency. The above analysis reflects the frequency correlation and amplitude correlation of the dynamic stiffness of the membrane air spring. This section of the theory decouples these two parts and proposes clear analytical expressions for each part. Next, the method for processing the test data is introduced. After the hysteresis curve is obtained by performing an air spring dynamometer test, the dynamic stiffness of the air spring must first be calculated based on the characteristics of the curve. Assume that the hysteresis characteristic diagram of the air spring dynamometer test is as follows Figure 6 As shown, the origin of the coordinate system is the initial equilibrium position. Indicates the air spring travel.

[0050] According to the general calculation method of hysteresis characteristics, the maximum and minimum values ​​of force F and displacement z (subscript max, min) and the area enclosed by the hysteresis curve are used. The real part of dynamic stiffness and the imaginary part Identify. Use the experimental hysteresis curve to analyze the real part and imaginary part of the dynamic stiffness of the air spring, and then compare and analyze it with the theory. The real part of the dynamic stiffness is similar to the stiffness of a spring, and the imaginary part of the dynamic stiffness represents the damping characteristics, which is why the hysteresis curve is not a diagonal line. The hysteresis area is the lost energy. The identification method is shown in formula (17): ; (17) in, is the dynamic stiffness of the air spring; Dynamic stiffness The real part of Dynamic stiffness The imaginary part of is the maximum vertical force relative to the equilibrium position of the air spring; is the minimum vertical force relative to the equilibrium position of the air spring; is the damping hysteresis angle; is the area enclosed by the hysteresis curve; is the maximum value of the air spring travel z; is the minimum value of the air spring travel z.

[0051] Step 203: determining the fatigue life of the air spring to be evaluated based on the fatigue loading parameter.

[0052] Specifically, the fatigue parameters are compared with a pre-constructed fatigue life mapping relationship table to obtain the fatigue life matching the fatigue parameters; wherein the pre-constructed fatigue life mapping relationship table is used to characterize the mapping relationship between dynamic stiffness of different sizes and fatigue loading parameters of different sizes.

[0053] In the above embodiment, the dynamic stiffness and structural parameters of the air spring to be evaluated are obtained; the dynamic stiffness and structural parameters are input into the air spring performance degradation model to obtain the fatigue loading parameters output by the air spring performance degradation model; wherein the air spring performance degradation model is a pre-constructed model of the mathematical relationship between the fatigue loading parameters of the air spring and the dynamic stiffness of the air spring; based on the fatigue loading parameters, the fatigue life of the air spring to be evaluated is determined. This method can pre-estimate the fatigue characteristics of the air spring according to the actual application scenarios of the vehicle at the early stage of vehicle design, thereby helping to design a stable and reliable air spring, improve product reliability, and shorten the development cycle, so that enterprises do not need to undergo many experiments to design air springs, saving development costs.

[0054] The air spring performance degradation analysis device based on structural characteristics provided by the present invention is described below. The air spring performance degradation analysis device based on structural characteristics described below and the air spring performance degradation analysis method based on structural characteristics described above can be referenced to each other.

[0055] like Figure 7 As shown, Figure 7 The structural schematic diagram of the air spring performance degradation analysis device based on structural characteristics provided by the present invention comprises: A parameter acquisition module 701 is used to acquire the dynamic stiffness and structural parameters of the air spring to be evaluated; a fatigue loading parameter calculation module 702, for inputting the dynamic stiffness and the structural parameter into an air spring performance degradation model to obtain a fatigue loading parameter output by the air spring performance degradation model; wherein the air spring performance degradation model is a pre-constructed model of the mathematical relationship between the fatigue loading parameter of the air spring and the dynamic stiffness of the air spring; The fatigue life determination module 703 is used to determine the fatigue life of the air spring to be evaluated based on the fatigue loading parameter.

[0056] In one embodiment, the fatigue life determination module 703 is further used to: compare the fatigue parameter with a pre-constructed fatigue life mapping relationship table to obtain the fatigue life matching the fatigue parameter; The pre-constructed fatigue life mapping relationship table is used to characterize the mapping relationship between dynamic stiffnesses of different sizes and fatigue loading parameters of different sizes.

[0057] In one embodiment, the parameter acquisition module 701 is further used to: collect the dynamic stiffness of the air spring to be evaluated by using a frequency response analyzer; and collect the structural parameters of the air spring to be evaluated.

[0058] In one embodiment, the air spring performance degradation model is as shown in the above formulas (1)-(5), which will not be described in detail here.

[0059] In one embodiment, the parameter acquisition module 701 is further used to: The dynamic stiffness of the air spring to be evaluated is obtained by analyzing the air spring hysteresis curve.

[0060] In one embodiment, the air spring to be evaluated is a membrane air spring.

[0061] Figure 8 An example of a physical structure diagram of an electronic device is shown in FIG. Figure 8As shown, the electronic device may include: a processor 810, a communication interface 820, a memory 830 and a communication bus 840, wherein the processor 810, the communication interface 820 and the memory 830 communicate with each other through the communication bus 840. The processor 810 may call the logic instructions in the memory 830 to execute the air spring performance degradation analysis method based on structural characteristics, the method comprising: obtaining the dynamic stiffness and structural parameters of the air spring to be evaluated; inputting the dynamic stiffness and the structural parameters into the air spring performance degradation model to obtain the fatigue loading parameters output by the air spring performance degradation model; wherein the air spring performance degradation model is a pre-constructed model of the mathematical relationship between the fatigue loading parameters of the air spring and the dynamic stiffness of the air spring; based on the fatigue loading parameters, determining the fatigue life of the air spring to be evaluated.

[0062] In addition, the logic instructions in the above-mentioned memory 830 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 method described in 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.

[0063] On the other hand, the present invention also provides a computer program product, which includes a computer program, which can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the air spring performance degradation analysis method based on structural characteristics provided by the above-mentioned methods, and the method includes: obtaining the dynamic stiffness and structural parameters of the air spring to be evaluated; inputting the dynamic stiffness and the structural parameters into an air spring performance degradation model to obtain fatigue loading parameters output by the air spring performance degradation model; wherein the air spring performance degradation model is a pre-constructed model of the mathematical relationship between the fatigue loading parameters of the air spring and the dynamic stiffness of the air spring; based on the fatigue loading parameters, determining the fatigue life of the air spring to be evaluated.

[0064] In another aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which is implemented when executed by a processor to perform the air spring performance degradation analysis method based on structural characteristics provided by the above methods, the method comprising: obtaining the dynamic stiffness and structural parameters of the air spring to be evaluated; inputting the dynamic stiffness and structural parameters into the air spring performance degradation model to obtain the fatigue loading parameters output by the air spring performance degradation model; wherein the air spring performance degradation model is a pre-constructed model of the mathematical relationship between the fatigue loading parameters of the air spring and the dynamic stiffness of the air spring; based on the fatigue loading parameters, determining the fatigue life of the air spring to be evaluated. .

[0065] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, 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. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0066] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including 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 described in each embodiment or some parts of the embodiments.

[0067] 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 analyzing air spring performance degradation based on structural characteristics, characterized in that: include: Obtain the dynamic stiffness and structural parameters of the air spring to be evaluated; Inputting the dynamic stiffness and the structural parameter into an air spring performance degradation model to obtain a fatigue loading parameter output by the air spring performance degradation model; wherein the air spring performance degradation model is a pre-constructed model of the mathematical relationship between the fatigue loading parameter of the air spring and the dynamic stiffness of the air spring; Based on the fatigue loading parameter, the fatigue life of the air spring to be evaluated is determined.

2. The air spring performance degradation analysis method based on structural characteristics according to claim 1 is characterized in that: The step of determining the fatigue life of the air spring to be evaluated based on the fatigue loading parameter includes: Comparing the fatigue parameter with a pre-constructed fatigue life mapping relationship table to obtain the fatigue life matching the fatigue parameter; The pre-constructed fatigue life mapping relationship table is used to characterize the mapping relationship between dynamic stiffnesses of different sizes and fatigue loading parameters of different sizes.

3. The air spring performance degradation analysis based on structural characteristics according to claim 1, characterized in that: The obtaining of the dynamic stiffness and structural parameters of the air spring to be evaluated includes: Using a frequency response analyzer to collect the dynamic stiffness of the air spring to be evaluated; The structural parameters of the air spring to be evaluated are collected.

4. The air spring performance degradation analysis method based on structural characteristics according to claim 1, characterized in that: The air spring performance degradation model is: ； （1） ； （2） ； （3） ； （4） ；（5） in, is the dynamic stiffness of the air spring, is the excitation frequency, is the effective area of ​​the air spring, is the effective area of ​​the air spring Stiffness due to vertical displacement changes; It is the stiffness generated by the high pressure gas inside the air bag; It is the equivalent damping generated by the heat exchange between the high-pressure gas inside the air bag and the outside world; Indicates the pressure inside the air spring body volume; is the initial pressure of the gas inside the air spring; Indicates the atmospheric pressure of the external environment; is the gas polyvariability index; is the initial airbag volume of the airbag; is the specific heat at constant volume; is the initial gas mass in the air bag; is the equivalent heat transfer coefficient; is the additional stiffness caused by the drop ear bending moment; N is the number of fatigue loading; is the effective radius of the air spring; It is the thickness of the internal reinforcement composite material between the inner and outer rubber layers in the airbag structure; is the volume fraction of the cord; is the initial Young's modulus of the cord; c is the correction factor for the number of fatigue loading times N; is the cord inclination angle; is the Young's modulus of the airbag rubber material of the air spring at zero strain; is the Young's modulus of the airbag rubber material under infinite strain; b is the hardening coefficient related to the rubber material and loading conditions; It is the total fatigue life of the rubber material, which is usually measured by test or specified manually; is the piston inclination angle; A is the excitation amplitude, is the characteristic amplitude of the rubber airbag; is the total thickness of the airbag; The thickness of the reinforced composite material layer inside the airbag layer is; is an empirical parameter related to the fractal dimension of rubber.

5. The air spring performance degradation analysis method based on structural characteristics according to claim 3 is characterized in that: The method of collecting the dynamic stiffness of the air spring to be evaluated by using a frequency response analyzer includes: The dynamic stiffness of the air spring to be evaluated is obtained by analyzing the air spring hysteresis curve.

6. The air spring performance degradation analysis method based on structural characteristics according to any one of claims 1 to 5, characterized in that: The air spring to be evaluated is a membrane type air spring.

7. An air spring performance degradation analysis device based on structural characteristics, characterized in that: include: A parameter acquisition module, used to obtain the dynamic stiffness and structural parameters of the air spring to be evaluated; a fatigue loading parameter calculation module, used for inputting the dynamic stiffness and the structural parameter into an air spring performance degradation model to obtain a fatigue loading parameter output by the air spring performance degradation model; wherein the air spring performance degradation model is a pre-constructed model of the mathematical relationship between the fatigue loading parameter of the air spring and the dynamic stiffness of the air spring; The fatigue life determination module is used to determine the fatigue life of the air spring to be evaluated based on the fatigue loading parameter.

8. 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 air spring performance degradation analysis method based on structural characteristics as described in any one of claims 1 to 6 is implemented.

9. 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 air spring performance degradation analysis method based on structural characteristics as claimed in any one of claims 1 to 6 is implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the air spring performance degradation analysis method based on structural characteristics as claimed in any one of claims 1 to 6 is implemented.

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