CN116628893A

CN116628893A - Fatigue life analysis method and device for coil spring and electronic equipment

Info

Publication number: CN116628893A
Application number: CN202310805407.0A
Authority: CN
Inventors: 肖雄; 曾庆强; 毛显红; 黄永旺
Original assignee: Chongqing Changan Automobile Co Ltd
Current assignee: Chongqing Changan Automobile Co Ltd
Priority date: 2023-06-30
Filing date: 2023-06-30
Publication date: 2023-08-22

Abstract

The invention relates to a fatigue life analysis method, a device and electronic equipment for a coil spring, which are characterized in that a coil spring three-dimensional model, an upper cushion three-dimensional model and a lower cushion three-dimensional model for the coil spring, the upper cushion and the lower cushion are obtained; determining material properties and section properties of the coil spring three-dimensional model, the upper cushion three-dimensional model and the lower cushion three-dimensional model; determining the assembly condition and the movement path of the vehicle; determining contact properties for the coil spring three-dimensional model, the upper cushion three-dimensional model and the lower cushion three-dimensional model based on assembly conditions, motion paths, material properties, section properties; the fatigue life analysis result of the spiral spring is determined through the contact attribute, so that the accuracy of the fatigue life analysis of the spiral spring is improved, the analysis efficiency is improved, and the cost is further reduced.

Description

Fatigue life analysis method and device for coil spring and electronic equipment

Technical Field

The present invention relates to the field of fatigue testing technology, and in particular, to a method for analyzing fatigue life of a coil spring, an apparatus for analyzing fatigue life of a coil spring, an electronic device, and a computer-readable storage medium.

Background

The spiral spring is used as an elastic element and widely applied to automobile design, particularly a suspension system of a passenger car, the wheel and the car body are elastically connected, vertical loads between the wheel and the car body are mainly transmitted, meanwhile, energy can be absorbed and stored by means of deformation, impact caused by wheel jump is further relieved, riding comfort is improved, in road running, the spiral spring is continuously subjected to random excitation from a road surface, fatigue failure is easy to occur, once the spiral spring exceeds the service life, the fatigue failure occurs, the car jolt is caused, operability is reduced, even the car body is difficult to control, and therefore safety problems are caused, and the determination of the fatigue life of the spiral spring has important significance for improving passenger riding experience and preventing the car from generating safety accidents.

Therefore, how to analyze the fatigue life of a coil spring is a problem that one skilled in the art needs to overcome.

Disclosure of Invention

The embodiment of the invention provides a fatigue life analysis method and device for a coil spring, electronic equipment and a computer readable storage medium, so as to solve the problem of how to analyze the fatigue life of the coil spring.

In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:

the invention provides a fatigue life analysis method for a coil spring, wherein the coil spring is provided with an upper cushion and a lower cushion which correspond to each other, and the method can comprise the following steps:

acquiring a coil spring three-dimensional model, an upper cushion three-dimensional model and a lower cushion three-dimensional model for the coil spring, the upper cushion and the lower cushion;

determining material properties and cross-sectional properties of the coil spring three-dimensional model, the upper cushion three-dimensional model, and the lower cushion three-dimensional model;

determining the assembly condition and the movement path of the vehicle;

determining contact properties for the coil spring three-dimensional model, the upper cushion three-dimensional model, and the lower cushion three-dimensional model based on the assembly condition, the motion path, the material properties, and the cross-sectional properties;

determining a fatigue life analysis result for the coil spring by the contact property.

Optionally, the method may further include:

performing grid division on the spiral spring three-dimensional model, the upper cushion three-dimensional model and the lower cushion three-dimensional model to generate a first unit node aiming at the spiral spring three-dimensional model, a second unit node aiming at the upper cushion three-dimensional model and a third unit node aiming at the lower cushion three-dimensional model; the first unit node is a reduced integral unit, and the second unit node and the third unit node are linear tetrahedral units.

Optionally, the step of determining the fatigue life analysis result for the coil spring by the contact property may include:

determining constraint parameters of the three-dimensional model of the coil spring based on the contact attributes;

determining a load boundary condition of the three-dimensional model of the coil spring based on the contact attribute;

performing finite element analysis on the coil spring three-dimensional model based on the constraint parameters and the load boundary conditions, and generating stress data for the first unit node;

and determining a fatigue life analysis result for the coil spring based on the stress data.

Optionally, the coil spring has a corresponding spring tray, the first unit node includes an upper load point and a lower load point, and the step of determining the constraint parameter of the three-dimensional model of the coil spring based on the contact attribute may include:

determining a first slave node from the second unit nodes through the contact attribute; the first slave node is a unit node used for expressing the upper cushion and the vehicle contact surface in the upper cushion three-dimensional model;

determining the load point as a first master node;

determining a first constraint parameter for the first master node based on the first slave node;

Determining a second slave node from the third unit node through the contact attribute; the second slave node is a unit node used for expressing the contact surface of the lower cushion and the spring tray in the lower cushion three-dimensional model;

determining the load point as a second master node;

determining a second constraint parameter for the second master node based on the second slave node;

the first constraint parameter and the second constraint parameter are used as constraint parameters for the coil spring three-dimensional model based on the contact attribute.

Optionally, the step of determining a load boundary condition of the three-dimensional model of the coil spring based on the contact property may include:

establishing a local coordinate system aiming at the lower load point;

determining a random road load for the local coordinate system;

and taking the random road load as a load boundary condition of the coil spring three-dimensional model.

Optionally, the step of determining the random road load for the local coordinate system may include:

determining a whole vehicle multi-body dynamics model for the vehicle;

performing simulation analysis on the whole vehicle multi-body dynamics model by adopting a preset virtual test field pavement model, and determining displacement parameters and angle parameters between an upper load point and a lower load point corresponding to the coil spring three-dimensional model;

Performing reduction processing based on the displacement parameter and the angle parameter to obtain a wave peak value and a wave trough value;

and taking the peak value and the trough value as the random road load.

Optionally, the method may further include:

determining a stress fatigue curve corresponding to the material property;

the step of determining a fatigue life analysis result for the coil spring based on the stress data includes:

and determining a fatigue life analysis result for the spiral spring by adopting the stress fatigue curve and the stress data.

Optionally, the step of determining a stress fatigue curve corresponding to the material property may comprise:

acquiring life parameters and stress ratios for the material properties;

determining a first parameter to be determined and a second parameter to be determined based on the stress ratio and the material property;

a stress fatigue curve corresponding to the material property is determined based on the first pending parameter, the second pending parameter, the stress data, and the lifetime parameter.

acquiring ultimate strength, stress ratio and action form coefficient aiming at the material property;

The present invention also provides a fatigue life analysis device for a coil spring having corresponding upper and lower cushions, which may include:

a three-dimensional model acquisition module for acquiring a coil spring three-dimensional model, an upper cushion three-dimensional model, and a lower cushion three-dimensional model for the coil spring, the upper cushion, and the lower cushion;

a section attribute determination module for determining material attributes and section attributes of the coil spring three-dimensional model, the upper cushion three-dimensional model, and the lower cushion three-dimensional model;

a movement path determination module for determining an assembly condition and a movement path of the vehicle;

a contact attribute determination module for determining contact attributes for the coil spring three-dimensional model, the upper cushion three-dimensional model, and the lower cushion three-dimensional model based on the assembly condition, the movement path, the material attribute, and the cross-sectional attribute;

And the analysis result determining module is used for determining the fatigue life analysis result of the coil spring through the contact attribute.

Optionally, the method may further include:

the grid division module is used for carrying out grid division on the spiral spring three-dimensional model, the upper cushion three-dimensional model and the lower cushion three-dimensional model, and generating a first unit node aiming at the spiral spring three-dimensional model, a second unit node aiming at the upper cushion three-dimensional model and a third unit node aiming at the lower cushion three-dimensional model; the first unit node is a reduced integral unit, and the second unit node and the third unit node are linear tetrahedral units.

Optionally, the analysis result determining module may include:

a constraint parameter determination submodule for determining constraint parameters of the three-dimensional model of the coil spring based on the contact attribute;

a load boundary condition determination sub-module for determining a load boundary condition of the three-dimensional model of the coil spring based on the contact property;

the finite element analysis sub-module is used for carrying out finite element analysis on the coil spring three-dimensional model based on the constraint parameters and the load boundary conditions, and generating stress data aiming at the first unit node;

An analysis result determination sub-module for determining a fatigue life analysis result for the coil spring based on the stress data.

Optionally, the coil spring has a corresponding spring tray, the first unit node includes an upper load point and a lower load point, and the constraint parameter determination submodule may include:

the first slave node determining unit is used for determining a first slave node from the second unit nodes through the contact attribute; the first slave node is a unit node used for expressing the upper cushion and the vehicle contact surface in the upper cushion three-dimensional model;

a first master node determining unit, configured to determine the load point as a first master node;

a first constraint parameter determination unit configured to determine a first constraint parameter for the first master node based on the first slave node;

a second slave node determining unit, configured to determine a second slave node from the third unit node through the contact attribute; the second slave node is a unit node used for expressing the contact surface of the lower cushion and the spring tray in the lower cushion three-dimensional model;

a second master node determining unit configured to determine the load point as a second master node;

A second constraint parameter determination unit configured to determine a second constraint parameter for the second master node based on the second slave node;

and a constraint parameter determination unit configured to take the first constraint parameter and the second constraint parameter as constraint parameters for the coil spring three-dimensional model based on the contact attribute.

Optionally, the load boundary condition determination submodule may include:

a local coordinate system establishing unit for establishing a local coordinate system for the lower load point;

a random road load determining unit configured to determine a random road load for the local coordinate system;

and the load boundary condition determining unit is used for taking the random road load as the load boundary condition of the coil spring three-dimensional model.

Alternatively, the random road load determining unit may include:

a model determination subunit configured to determine a whole vehicle multi-body dynamics model for the vehicle;

the simulation analysis subunit is used for performing simulation analysis on the whole vehicle multi-body dynamics model by adopting a preset virtual test field pavement model and determining displacement parameters and angle parameters between an upper load point and a lower load point corresponding to the coil spring three-dimensional model;

The reduction processing subunit is used for carrying out reduction processing based on the displacement parameter and the angle parameter to obtain a wave peak value and a wave trough value;

a random road load determining subunit, configured to take the peak value and the trough value as the random road load.

Optionally, the method may further include:

a stress fatigue curve determination sub-module for determining a stress fatigue curve corresponding to the material property;

the analysis result determination submodule includes:

and an analysis result determination unit configured to determine a fatigue life analysis result for the coil spring using the stress fatigue curve and the stress data.

Optionally, the stress fatigue curve determination sub-module may include:

a life parameter acquisition unit configured to acquire a life parameter and a stress ratio for the material property;

a first pending parameter determination unit for determining a first pending parameter and a second pending parameter based on the stress ratio and the material property;

and a first stress fatigue curve determining unit, configured to determine a stress fatigue curve corresponding to the material property based on the first predetermined parameter, the second predetermined parameter, the stress data, and the lifetime parameter.

Optionally, the stress fatigue curve determination sub-module may include:

a ultimate strength acquisition unit for acquiring ultimate strength, stress ratio and action form coefficient for the material property;

a second pending parameter determination unit for determining a first pending parameter and a second pending parameter based on the stress ratio and the material property;

and a second stress fatigue curve determining unit configured to determine a stress fatigue curve corresponding to the material property based on the first parameter to be determined, the second parameter to be determined, the stress data, and the lifetime parameter.

The present invention also provides an electronic device including:

at least one processor; the method comprises the steps of,

a memory communicatively coupled to the at least one processor; wherein,,

the memory stores instructions executable by the at least one processor to enable the at least one processor to implement the fatigue life analysis method for a coil spring described above.

The present invention also provides a computer-readable storage medium storing a computer program which, when executed by a processor, is capable of implementing the above-described fatigue life analysis method for a coil spring.

The invention has the beneficial effects that:

according to the embodiment of the invention, the coil spring three-dimensional model, the upper cushion three-dimensional model and the lower cushion three-dimensional model aiming at the coil spring, the upper cushion and the lower cushion are obtained; determining material properties and cross-sectional properties of the coil spring three-dimensional model, the upper cushion three-dimensional model, and the lower cushion three-dimensional model; determining the assembly condition and the movement path of the vehicle; determining contact properties for the coil spring three-dimensional model, the upper cushion three-dimensional model, and the lower cushion three-dimensional model based on the assembly condition, the motion path, the material properties, and the cross-sectional properties; and determining the fatigue life analysis result of the coil spring through the contact attribute, so that the accuracy of the fatigue life analysis of the coil spring is improved, the analysis efficiency is improved, and the cost is further reduced.

Drawings

One or more embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings, in which like references indicate similar elements, and in which the figures of the drawings are not to be taken in a limiting sense, unless otherwise indicated.

FIG. 1 is a flow chart of steps of a method for analyzing fatigue life of a coil spring provided in an embodiment of the present invention;

FIG. 2 is a flow chart of steps of another method for analyzing fatigue life for a coil spring provided in an embodiment of the present invention;

FIG. 3 is a block diagram of a fatigue life analysis device for a coil spring provided in an embodiment of the present invention;

fig. 4 is a block diagram of a hardware structure of an electronic device according to an embodiment of the present invention.

Detailed Description

Referring to fig. 1, a flowchart illustrating steps of a method for analyzing fatigue life of a coil spring according to an embodiment of the present invention may specifically include the following steps:

step 101, obtaining a coil spring three-dimensional model, an upper cushion three-dimensional model and a lower cushion three-dimensional model for the coil spring, the upper cushion and the lower cushion;

step 102, determining material properties and section properties of the coil spring three-dimensional model, the upper cushion three-dimensional model and the lower cushion three-dimensional model;

step 103, determining the assembly condition and the movement path of the vehicle;

step 104 of determining contact properties for the coil spring three-dimensional model, the upper cushion three-dimensional model, and the lower cushion three-dimensional model based on the assembly condition, the movement path, the material properties, and the cross-sectional properties;

Step 105, determining a fatigue life analysis result for the coil spring through the contact attribute.

In practical application, the fatigue life is analyzed by adopting a three-dimensional graph in the design stage, so that the investment for manufacturing a sample to be tested can be saved, the test period is shortened, and the cost of the analysis process is reduced.

In a specific implementation, the coil spring in the embodiment of the invention can be configured on a vehicle, and the coil spring can be provided with an upper cushion and a lower cushion corresponding to the coil spring; determining material properties and section properties of the coil spring three-dimensional model, the upper cushion three-dimensional model and the lower cushion three-dimensional model; determining the assembly condition and the movement path of the vehicle; determining contact properties for the coil spring three-dimensional model, the upper cushion three-dimensional model, and the lower cushion three-dimensional model based on the assembly conditions, the motion path, the material properties, and the cross-sectional properties; by determining the fatigue life analysis result for the coil spring through the contact property, the embodiment of the invention can be performed in a design stage, the three-dimensional models for the coil spring, the upper cushion and the lower cushion can be designed three-dimensional patterns of the coil spring, the upper cushion and the lower cushion, then the manufacturing material of the coil spring can be used as the material property of the three-dimensional models of the coil spring, for example, the material property of the coil spring can be 55CrSi (oil quenching tempered chrome silicon spring steel), the manufacturing material of the upper cushion and the lower cushion can be used as the material property of the three-dimensional models of the upper cushion and the lower cushion, for example, the material property of the three-dimensional models of the upper cushion and the lower cushion can be rubber, meanwhile, the elastic modulus and the Poisson ratio of the coil spring can be used as the section property of the three-dimensional models of the coil spring, for example, the section property of the coil spring can be 204000MPa, the Poisson ratio is 0.3, the elastic modulus and the Poisson ratio can be used as the section property of the three-dimensional models of the upper cushion and the lower cushion, for example, the upper cushion and the Poisson ratio can be used as the section property of the three-dimensional models of the upper cushion and the lower cushion, for example, the upper cushion and the Poisson ratio can be the section property of the three-dimensional models, the elastic modulus can be measured as the specific material model or the specific modulus is 5800.

In practical application, the stress of the coil spring is complex in the running process of the vehicle, and if the fatigue life analysis accuracy of the coil spring under the complex stress environment is required to be improved, the assembly condition and the movement path of the vehicle can be considered, so that the analysis result is more real and accurate.

The embodiment of the invention can determine the assembly condition and the movement path of the vehicle configured by the coil spring, wherein the assembly condition can comprise assembly position information, assembly process information and the like, and the movement path can be movement track information, movement direction information and the like.

Of course, the foregoing is merely exemplary, and those skilled in the art may use other information related to the assembly of the coil spring and the vehicle as the assembly condition, and may use other information related to the movement of the vehicle as the movement path, which is not limited to the embodiment of the present invention.

Based on the assembly, path of movement, material properties and cross-sectional properties, contact properties for the coil spring three-dimensional model, the upper cushion three-dimensional model and the lower cushion three-dimensional model may be determined, and illustratively, contact properties may be contact pairs between the coil spring three-dimensional model and the upper cushion three-dimensional model, the lower cushion three-dimensional model, contact surfaces, self-contacts and friction coefficients, wherein the contact pairs define boundaries for components that may be in contact, e.g., the contact pairs between the coil spring three-dimensional model and the upper cushion three-dimensional model, the lower cushion three-dimensional model may be the state that the coil spring end turns are just in contact but cannot penetrate the upper cushion, and/or the lower cushion, wherein the contact pairs may include a major surface and a minor surface, may be the coil spring three-dimensional model, the minor surface may be the upper cushion three-dimensional model, and/or the lower cushion three-dimensional model, the contact surfaces may be the coil spring three-dimensional model and/or the upper cushion three-dimensional model, and/or the surfaces between the lower cushion three-dimensional model, the self-contacts may define all surfaces of the coil spring three-dimensional model except for surfaces that may be in contact surfaces, the friction coefficients may include the coil spring three-dimensional model and the upper cushion three-dimensional model, the friction coefficients may be determined, e.g., the friction coefficients may be determined for a three-dimensional model, e.g., contact coefficients may be 0, and may be determined for a fatigue, and may be based on the friction coefficients.

On the basis of the above embodiments, modified embodiments of the above embodiments are proposed, and it is to be noted here that only the differences from the above embodiments are described in the modified embodiments for the sake of brevity of description.

In an alternative embodiment of the present invention, further comprising:

In practical application, the complex model is divided into a plurality of units, and the behavior of each unit can be described by a simple mathematical formula, so that a numerical method can be used for solving, the convenience can be provided for the later finite element analysis, the matching degree of calculation is improved, and the quality of the operation result of the finite element analysis is ensured.

In a specific implementation, the embodiment of the invention can carry out grid division on the spiral spring three-dimensional model, the upper cushion three-dimensional model and the lower cushion three-dimensional model to generate a first unit node aiming at the spiral spring three-dimensional model, a second unit node aiming at the cushion three-dimensional model and a third unit node aiming at the lower cushion three-dimensional model; the first unit node is a reduced integration unit, the second unit node and the third unit node are linear tetrahedral units, illustratively, the coil spring three-dimensional model can be divided by adopting hexahedral meshes, the number of cross-sectional meshes is not less than 20, the total number of meshes is not less than 5 ten thousand, as the first unit node, for example, the coil spring three-dimensional model in a free state can be divided by adopting hexahedral meshes, the number of cross-sectional meshes can be 52, the total number of meshes can be 50076, the upper cushion three-dimensional model and the lower cushion three-dimensional model can be divided by adopting tetrahedral meshes, the average unit size is not more than 2mm, the meshes of the upper cushion three-dimensional model are taken as the second unit node, the meshes of the lower cushion three-dimensional model are taken as the third unit node, for example, the meshes of the upper cushion three-dimensional model and the lower cushion three-dimensional model can be 93203, specifically, the first unit node can be a reduced integration unit C3D8R, the second unit node and the third unit node can be linear tetrahedral unit C3D4, wherein the linear tetrahedral unit C3D4 can be more easily contracted when analyzing the larger deformation problem, the linear deformation problem is analyzed, the linear deformation problem can be more easily calculated, and the linear deformation state is more easily can be observed, and the linear deformation state is more can be more easily, and the linear deformation state.

In the embodiment of the invention, the spiral spring three-dimensional model, the upper cushion three-dimensional model and the lower cushion three-dimensional model are subjected to grid division to generate a first unit node aiming at the spiral spring three-dimensional model, a second unit node aiming at the upper cushion three-dimensional model and a third unit node aiming at the lower cushion three-dimensional model; the first unit node is a reduced integral unit, and the second unit node and the third unit node are linear tetrahedral units, so that a data base is provided for subsequent analysis and calculation, the quality of an operation result is guaranteed, and the operation efficiency is improved.

In an alternative embodiment of the present invention, the step of determining the fatigue life analysis result for the coil spring by the contact property includes:

In practical application, finite element analysis can rapidly analyze the model, realize the failure part in the prediction model, is suitable for the parts with safety as the important point, is convenient for users to check and test the parts, reduces the number of requirements and test times for the prototype of the object to be tested in the test, reduces the test cost, and can realize standardization and normalization.

In a specific implementation, the embodiment of the invention can determine the constraint parameters of the three-dimensional model of the coil spring based on the contact attribute; determining a load boundary condition of the three-dimensional model of the coil spring based on the contact attribute; performing finite element analysis on the three-dimensional model of the spiral spring based on constraint parameters and load boundary conditions to generate stress data aiming at a first unit node; determining a fatigue life analysis result for the coil spring based on the stress data, by way of example, constraint parameters applied to the coil spring three-dimensional model may be determined based on contact properties corresponding to the coil spring three-dimensional model, the upper cushion three-dimensional model, and the lower cushion three-dimensional model, for example, a rigid unit may be applied on the coil spring three-dimensional model as the constraint parameters, load boundary conditions applied to the coil spring three-dimensional model may be determined based on contact properties corresponding to the coil spring three-dimensional model, the upper cushion three-dimensional model, and the lower cushion three-dimensional model, for example, a plurality of loads are loaded on the coil spring three-dimensional model as the load boundary conditions, then, based on the constraint parameters and the load boundary conditions, a finite element analysis is performed on the coil spring three-dimensional model, for example, a finite element analysis step of which an analysis type is static may be set, the number of finite element analysis steps may be identical to the number of load points corresponding to the load boundary conditions, an analysis parameter is set, a stress result of the coil spring three-dimensional model to which the constraint parameters are applied under the load boundary conditions may be calculated as stress data for the first unit node, and a fatigue life analysis result for the coil spring is determined based on the stress data.

According to the embodiment of the invention, constraint parameters of the three-dimensional model of the coil spring are determined based on the contact attribute; determining a load boundary condition of the three-dimensional model of the coil spring based on the contact attribute; performing finite element analysis on the coil spring three-dimensional model based on the constraint parameters and the load boundary conditions, and generating stress data for the first unit node; and determining a fatigue life analysis result aiming at the spiral spring based on the stress data, so that the number of requirements and test times of the object prototype to be tested are reduced, the efficiency of fatigue life analysis is improved, and the analysis cost is saved.

In an alternative embodiment of the present invention, the step of determining constraint parameters of the three-dimensional model of the coil spring based on the contact properties comprises:

determining the load point as a first master node;

determining the load point as a second master node;

In a specific implementation, the coil spring in the embodiment of the present invention may have a corresponding spring tray, and the first unit node may include an upper load point and a lower load point, and the embodiment of the present invention may determine the first slave node from the second unit node through a contact attribute; the first slave node is a unit node used for expressing an upper cushion and a vehicle contact surface in the upper cushion three-dimensional model; determining an upper load point as a first master node; determining a first constraint parameter for the first master node based on the first slave node; determining a second slave node from the third unit node through the contact attribute; the second slave node is a unit node used for expressing the contact surface of the lower cushion and the spring tray in the lower cushion three-dimensional model; determining the lower load point as a second master node; determining a second constraint parameter for the second master node based on the second slave node; when the contact attribute is a surface that the upper cushion contacts with the vehicle and a surface that the lower cushion contacts with the spring tray, the unit corresponding to the upper cushion and the vehicle contact surface may be set as a first slave node in a second unit node of the upper cushion three-dimensional model, an upper load point in the first unit node corresponding to the coil spring three-dimensional model may be set as a first master node, a rigid unit may be set up on the first master node, the rigid unit may be set as a first constraint parameter, then a unit corresponding to the lower cushion and the spring tray contact surface may be set as a second slave node in a third unit node of the lower cushion three-dimensional model, a lower load point in the first unit node corresponding to the coil spring three-dimensional model may be set up as a second master node, the rigid unit may be set up as a second constraint parameter, and the first constraint parameter and the second constraint parameter may be set up on the second master node.

According to the embodiment of the invention, the first slave node is determined from the second unit node based on the contact attribute; the first slave node is a unit node used for expressing the upper cushion and the vehicle contact surface in the upper cushion three-dimensional model; determining the load point as a first master node; determining a first constraint parameter for the first master node based on the first slave node; determining a second slave node from the third unit node through the contact attribute; the second slave node is a unit node used for expressing the contact surface of the lower cushion and the spring tray in the lower cushion three-dimensional model; determining the load point as a second master node; determining a second constraint parameter for the second master node based on the second slave node; and taking the first constraint parameter and the second constraint parameter as constraint parameters aiming at the three-dimensional model of the spiral spring based on the contact attribute, so that the actual contact condition based on the spiral spring is realized, the spiral spring is fixedly constrained, a foundation is laid for subsequent simulation, and the fatigue life analysis aiming at the spiral spring is more real and effective.

In an alternative embodiment of the present invention, the step of determining a load boundary condition of the coil spring three-dimensional model based on the contact property includes:

establishing a local coordinate system aiming at the lower load point;

determining a random road load for the local coordinate system;

In practical application, the stress environment of the coil spring is influenced by running of a vehicle, so that the coil spring is complex and changeable, the coil spring is not only compressed and stretched in the vertical direction, but also deformed by forces in multiple directions, and therefore, in order to improve the effectiveness and the authenticity of fatigue life analysis of the coil spring, the load condition of the coil spring in simulation analysis is required to be comprehensively considered.

In a specific implementation, the embodiment of the invention can establish a local coordinate system aiming at the lower load point; determining a random road load for the local coordinate system; taking the random road load as the load boundary condition of the coil spring three-dimensional model, wherein the first unit node corresponding to the coil spring three-dimensional model comprises an upper load point and a lower load point, a local coordinate system can be established by taking the upper load point as a coordinate origin, wherein the coordinate axis and the coordinate direction of the local coordinate system can be consistent with the coordinate system of a vehicle on which the coil spring is arranged, 6 random road loads can be loaded at the lower load point corresponding to the local coordinate system, the direction of the random road loads can be consistent with the local coordinate system, and the random road loads can be taken as the load boundary condition of the coil spring three-dimensional model.

According to the embodiment of the invention, a local coordinate system aiming at the lower load point is established; determining a random road load for the local coordinate system; and taking the random road load as a load boundary condition of the three-dimensional model of the spiral spring, thereby truly simulating the complex stress condition of the spiral spring and further improving the accuracy of analyzing the fatigue life of the spiral spring.

In an alternative embodiment of the invention, the step of determining a random road load for the local coordinate system comprises:

determining a whole vehicle multi-body dynamics model for the vehicle;

and taking the peak value and the trough value as the random road load.

In a specific implementation, the embodiment of the invention can determine a whole vehicle multi-body dynamics model aiming at a vehicle; adopting a preset virtual test field pavement model to carry out simulation analysis on the whole vehicle multi-body dynamics model, and determining displacement parameters and angle parameters between an upper load point and a lower load point corresponding to the coil spring three-dimensional model; performing reduction processing based on the displacement parameter and the angle parameter to obtain a wave peak value and a wave trough value; the wave peak value and the wave trough value are taken as random road loads, an integral multi-body dynamics model can be built in ADAMS software for example, the ADAMS software is called Automatic Dynamic Analysis of Mechanical Systems, also called mechanical system dynamics automatic analysis, the software is virtual prototype analysis software developed by American mechanical power company (Mechanical Dynamics Inc.), then the integral multi-body dynamics model is imported into a preset virtual test field pavement model, the integral multi-body dynamics model can be virtual test field VPG, the VPG is integral simulation software developed by ETA (Engineering Technology Associates Inc.), the function of the VPG virtual test field is to simulate all test items of an integral system, multi-body dynamics simulation analysis can be carried out in the virtual test field VPG, after simulation is finished, displacement and angle of a load point on a coil spring relative to a load point under pavement excitation in the virtual test field VPG are extracted, the displacement parameter and the angle parameter between the load point on the coil spring are respectively taken as a displacement parameter and the angle parameter between the load point on the coil spring three-dimensional model, the wave peak value and the wave trough value under all load processes can be reserved as wave peak value and the wave trough value under all load processes, and the random wave peak value and wave peak value are taken as random wave load values.

According to the embodiment of the invention, the whole vehicle multi-body dynamics model aiming at the vehicle is determined; performing simulation analysis on the whole vehicle multi-body dynamics model by adopting a preset virtual test field pavement model, and determining displacement parameters and angle parameters between an upper load point and a lower load point corresponding to the coil spring three-dimensional model; performing reduction processing based on the displacement parameter and the angle parameter to obtain a wave peak value and a wave trough value; and taking the wave peak value and the wave trough value as the random road load, so that the whole vehicle simulation is combined, and the real road surface excitation is simulated, thereby further improving the accuracy of the result of the coil spring fatigue life analysis.

In an alternative embodiment of the present invention, further comprising:

determining a stress fatigue curve corresponding to the material property;

In a specific implementation, the embodiment of the invention can determine a stress fatigue curve corresponding to the material property; the step of determining a fatigue life analysis result for the coil spring based on the stress data includes: determining a fatigue life analysis result for the coil spring using the stress fatigue curve and the stress data, by way of example, determining a stress fatigue curve for a material corresponding to material properties of the coil spring, the upper cushion, and the lower cushion, loading a plurality of loads on the coil spring three-dimensional model as load boundary conditions, and then performing finite element analysis on the coil spring three-dimensional model based on constraint parameters and the load boundary conditions, for example, setting a finite element analysis step of a static type, a number of finite element analysis steps, a number of load points corresponding to the load boundary conditions, setting an analysis parameter, outputting a stress analysis result under a random road load corresponding to each first unit node in the coil spring three-dimensional model as stress data for the first unit node, analyzing the fatigue life of the coil spring based on the stress fatigue curve and stress data to obtain a fatigue life analysis result, specifically, the stress data can be imported into nCode software (also called engineering integrated fatigue design software, which is a kind of fatigue endurance design software and test data processing software), a three-dimensional model fatigue analysis flow of the coil spring is built, a finite element input module is included for importing the stress analysis result of the three-dimensional model of the coil spring, an SN analysis module is included for analyzing fatigue damage in the three-dimensional model of the coil spring by using a stress life analysis method, a finite element output module is included for outputting the result of the fatigue damage, the SN analysis module can adopt the stress fatigue curve as a material parameter, the stress fatigue curve can be an SN curve (SN curves, the SN curve is a curve representing the relationship between the fatigue strength and the fatigue life of the standard test piece under certain cycle characteristics by taking the fatigue strength of the standard test piece of the material as an ordinate and taking the logarithmic value lg N of the fatigue life as an abscissa), the load mapping type in the SN analysis module can select 'Time Step', namely, the stress result corresponding to each load point of the road load is imported to perform fatigue calculation, the analysis parameter 'Combination Method' can select 'Critical Plane', namely, the stress in all directions of each first unit node traversing the three-dimensional model of the coil spring is selected to calculate the fatigue life, the direction with the maximum stress is submitted to calculation after analysis is completed, and the calculation result is used as the fatigue life analysis result.

According to the embodiment of the invention, the stress fatigue curve corresponding to the material property is determined; the step of determining a fatigue life analysis result for the coil spring based on the stress data includes: the fatigue life analysis result of the spiral spring is determined by adopting the stress fatigue curve and the stress data, so that each unit node of the spiral spring is traversed, and the stresses in different directions on each unit node are analyzed, so that the true stress born by the spiral spring in the running process of the vehicle is more consistent with the actual situation, and the fatigue life analysis result of the spiral spring is further more true and accurate.

In an alternative embodiment of the invention, the step of determining a stress fatigue curve corresponding to the material property comprises:

acquiring life parameters and stress ratios for the material properties;

In a specific implementation, the embodiment of the invention can acquire the life parameter, the stress ratio and the loading mode aiming at the material property; determining a first to-be-determined parameter and a second to-be-determined parameter based on the stress ratio, the loading mode and the material property; determining a stress fatigue curve corresponding to the material property based on the first pending parameter, the second pending parameter, the stress data and the life parameter, wherein the life parameter for the material property can be obtained, and the life parameter is recorded as N, the stress ratio R and the loading mode are obtained, then the first pending parameter is determined based on the stress ratio R, the loading mode and the material property, the first pending parameter is recorded as m, the second pending parameter is determined, the stress data is recorded as C, the stress data is recorded as S, and the stress data obtained through the symmetrical cycle fatigue test is fitted by adopting the following formula 1:

equation 1:

S ^m ·N＝C

when the stress ratio r= -1, a basic SN curve can be obtained, further, to take into account the average stress, denoted S _m The stress data S can be corrected using the following equation 2:

equation 2:

wherein S is _-1 For the fatigue limit when the stress ratio r= -1, S _m Is the average stress, S _u Is ultimate strength.

The SN curve may be: s is S _u ＝1900MPa，m＝7.314，C＝4.426×10 ²⁶ 。

According to the embodiment of the invention, the life parameter and the stress ratio aiming at the material property are obtained; determining a first parameter to be determined and a second parameter to be determined based on the stress ratio and the material property; and determining a stress fatigue curve corresponding to the material property based on the first pending parameter, the second pending parameter, the stress data and the life parameter, thereby realizing more accurate acquisition of the stress fatigue curve and providing reliable data support for subsequent analysis and calculation.

In specific implementation, the embodiment of the invention can acquire the ultimate strength, the stress ratio, the action form coefficient and the loading mode aiming at the material property; determining a first to-be-determined parameter and a second to-be-determined parameter based on the stress ratio, the loading mode and the material property; determining a stress fatigue curve corresponding to the material property based on the first parameter to be determined, the second parameter to be determined, the ultimate strength, and the form factor of action may, for example, obtain the ultimate strength for the material property, denoted as S _u The stress ratio R, the action form coefficient k and the loading mode are obtained, then a first undetermined parameter is determined based on the stress ratio R, the loading mode and the material attribute and is marked as m, a second undetermined parameter is determined and is marked as C, stress data is marked as S, and a stress fatigue curve can be obtained through calculation according to the following formula 3:

Equation 3:

C＝(0.9·S _u ) ^m ·10 ³

the action form coefficient k may be a coefficient reflecting different load action forms, and k may be taken as a value according to the following formula 4:

equation 4:

the SN curve may be: s is S _u ＝1900MPa，m＝7.314，C＝4.426×10 ²⁶ 。

According to the embodiment of the invention, the ultimate strength, the stress ratio and the action form coefficient aiming at the material property are obtained; determining a first parameter to be determined and a second parameter to be determined based on the stress ratio and the material property; and determining a stress fatigue curve corresponding to the material property based on the first pending parameter, the second pending parameter, the stress data and the life parameter, thereby realizing more accurate acquisition of the stress fatigue curve and providing reliable data support for subsequent analysis and calculation.

In order that those skilled in the art will better understand the embodiments of the present invention, a complete description of the embodiments of the present invention will be provided below.

During road running, the coil springs are constantly subjected to random excitation from the road surface, and fatigue failure is likely to occur. In the design stage of the coil spring, a bench endurance test and a road reliability test are generally performed to verify the endurance performance of the coil spring. If the fatigue life of the coil spring can be estimated by simulation means in the early design stage, the development time can be shortened, and the development cost can be saved.

Referring to fig. 2, a flowchart of steps of another fatigue life analysis method for a coil spring provided in an embodiment of the present invention is shown, and a specific flow is as follows:

the spiral spring and the upper cushion and the lower cushion are meshed, and materials and section properties are defined, specifically:

dividing the coil spring in a free state by using hexahedral grids, wherein the number of the cross-sectional grids is 52, the total number of the grids is 50076, and the unit type is a reduction integral unit (C3D 8R);

dividing the upper cushion and the lower cushion by using tetrahedral grids, wherein the average unit size is 2mm, the total grid number is 93203, and the unit type is a linear tetrahedral unit (C3D 4);

material properties and cross-sectional properties of the coil spring and cushion are defined. The coil spring used in the embodiment is made of 55CrSi, the elastic modulus is 204000MPa, and the Poisson ratio is 0.3; the soft pad is made of rubber, the elastic modulus is 5800MPa, and the Poisson ratio is 0.48. The section properties of the spiral spring and the upper cushion and the lower cushion are solid properties.

According to the assembly condition and the motion path of the whole vehicle, the contact attribute of the coil spring is defined, specifically:

defining a contact pair between the upper and lower cushions and the coil springs. The positions of the upper cushion and the lower cushion are adjusted to be just contacted with the end ring of the spiral spring but not penetrated, and the contact surface is the surface where contact between the spiral spring and the upper cushion and the lower cushion is possible. The main surface of the contact pair is a coil spring, the secondary surface is an upper cushion and a lower cushion, and the friction coefficient between the coil spring and the rubber cushion is 0.8.

Defining the self-contact of the coil spring. All surfaces of the coil spring except the end surface were defined as contact surfaces, the contact type was self-contact, and the friction coefficient was 0.15.

Setting constraint and load boundary conditions of a coil spring, carrying out finite element analysis, and extracting stress analysis results, wherein the method specifically comprises the following steps:

the method comprises the steps that a surface unit node, in contact with an upper cushion and a vehicle body, serves as a slave node, a spring load point serves as a master node, a rigid unit is built, and fixed constraint is applied to the master node;

the surface unit node where the lower cushion and the spring tray are in contact is taken as a slave node, and the spring load point is taken as a master node to establish a rigid unit. Defining a local coordinate system, wherein the coordinate origin is at a load point on a spring, the coordinate axis and the coordinate direction are consistent with the whole vehicle coordinate system, and random road loads in the directions of 6 local coordinate systems are respectively loaded at load points under the spring;

the loading load is a road random load, and the acquisition method comprises the following steps: and establishing a whole vehicle multi-body dynamics model in adams software, and introducing a virtual test field (VPG) pavement model to perform multi-body dynamics simulation. And after the simulation is finished, extracting the displacement and the angle of the lower point relative to the upper point of the coil spring under the excitation of the VPG pavement. And (3) carrying out reduction processing on the extracted load data, and reserving the wave crest and wave trough values under all loading courses.

Setting a finite element analysis step with the analysis type of static, keeping the number of the analysis steps consistent with the load data points, and outputting the stress result of each unit of the spiral spring under all random road loads.

Building a spiral spring fatigue analysis flow, setting analysis parameters, and calculating the fatigue life under road load, wherein the method specifically comprises the following steps:

and importing the stress results of each unit of the output spiral spring under all random road loads into nCode software, and building a spiral spring fatigue analysis flow, wherein the analysis flow comprises a finite element input module, an SN analysis module and a finite element output module. The finite element input module is used for importing a stress analysis result of the spiral spring, the SN analysis module is used for analyzing fatigue damage of the spiral spring by using a stress-service life analysis method, and the finite element output module is used for outputting the fatigue analysis result of the spiral spring.

Material parameters are set in the SN analysis module. The material parameter is the SN curve of the spiral spring material, and the stress-fatigue data obtained by the symmetrical cycle fatigue test can be fitted by using the power function formula of the formula 1:

wherein S is stress, N is service life, m and C are undetermined parameters, and the undetermined parameters are related to materials, stress ratio, loading mode and the like. The underlying SN curve is tested at a stress ratio R = -1, and the average stress S needs to be taken into account _m Using the Goodman model of equation 2 above to correct for stress S:

wherein S is _-1 Is the fatigue limit when the stress ratio R= -1, S _m Is the average stress, S _u Is ultimate strength.

The SN curve can also be determined by the ultimate strength S of the material _u The approximation can be calculated using equation 3 above:

where k is a coefficient reflecting different load modes, and the value of k may be obtained according to the above formula 4.

In the embodiment, the SN curve parameters of the material are approximately obtained by using the ultimate strength of the coil spring material under the tensile load: s is S _u ＝1900MPa，m＝7.314，C＝4.426×10 ²⁶ 。

The load mapping type in the SN analysis module selects 'Time Step', namely, the stress result corresponding to each load point of the road load is imported to perform fatigue calculation. The analysis parameter "Combination Method" selects "Critical Plane", i.e., the stress in all directions of each element of the coil spring is traversed, and the direction of maximum stress is selected to calculate the fatigue life.

And after the setting is completed, calculating to obtain a fatigue analysis result of the coil spring under random road load.

Firstly, mesh division is carried out on a coil spring in a free state and an upper cushion and a lower cushion, and material and section properties are defined; then, according to the whole vehicle assembly condition and the motion path, defining the contact attribute of the coil spring, setting the constraint and load boundary condition of the coil spring, carrying out finite element analysis, and extracting the stress analysis result; and finally, constructing a spiral spring fatigue analysis flow, setting analysis parameters, and calculating to obtain a fatigue damage result under random road load. Compared with the prior art, the load input used by the invention is random road load, and the fatigue life of the spiral spring under the excitation of the random road load is considered to be more consistent with the actual situation. In addition, the fatigue damage of all areas of the coil spring is directly calculated by using software, so that damage distribution and risk positions can be intuitively seen, and a reference is provided for optimal design.

It should be noted that, for simplicity of description, the method embodiments are shown as a series of acts, but it should be understood by those skilled in the art that the embodiments are not limited by the order of acts, as some steps may occur in other orders or concurrently in accordance with the embodiments. Further, those skilled in the art will appreciate that the embodiments described in the specification are presently preferred embodiments, and that the acts are not necessarily required by the embodiments of the invention.

Referring to fig. 3, a block diagram of a fatigue life analysis device for a coil spring according to an embodiment of the present invention is shown, which may specifically include the following modules:

a three-dimensional model acquisition module 301 for acquiring a coil spring three-dimensional model, an upper cushion three-dimensional model, and a lower cushion three-dimensional model for the coil spring, the upper cushion, and the lower cushion;

a cross-sectional property determination module 302 for determining material properties and cross-sectional properties of the coil spring three-dimensional model, the upper cushion three-dimensional model, and the lower cushion three-dimensional model;

a movement path determination module 303 for determining the assembly condition and movement path of the vehicle;

A contact attribute determination module 304 for determining contact attributes for the coil spring three-dimensional model, the upper cushion three-dimensional model, and the lower cushion three-dimensional model based on the assembly condition, the movement path, the material attribute, and the cross-sectional attribute;

an analysis result determination module 305 for determining a fatigue life analysis result for the coil spring by the contact property.

Optionally, the method may further include:

Optionally, the analysis result determining module may include:

Optionally, the load boundary condition determination submodule may include:

Alternatively, the random road load determining unit may include:

Optionally, the method may further include:

the analysis result determination submodule includes:

Optionally, the stress fatigue curve determination sub-module may include:

For the device embodiments, since they are substantially similar to the method embodiments, the description is relatively simple, and reference is made to the description of the method embodiments for relevant points.

In addition, the embodiment of the invention also provides electronic equipment, which comprises: the processor, the memory, store on the memory and can be on the computer program of the operation of processor, this computer program is realized each process of the above-mentioned fatigue life analysis method embodiment to coil spring when being carried out by the processor, and can reach the same technical result, in order to avoid repetition, will not be repeated here.

The embodiment of the invention also provides a computer readable storage medium, on which a computer program is stored, which when executed by a processor, realizes the above-mentioned various processes of the embodiment of the fatigue life analysis method for the coil spring, and can achieve the same technical effects, and in order to avoid repetition, the description is omitted here. Wherein the computer readable storage medium is selected from Read-Only Memory (ROM), random access Memory (Random Access Memory, RAM), magnetic disk or optical disk.

Fig. 4 is a schematic hardware structure of an electronic device implementing various embodiments of the present invention.

The electronic device 400 includes, but is not limited to: radio frequency unit 401, network module 402, audio output unit 403, input unit 404, sensor 405, display unit 406, user input unit 407, interface unit 408, memory 409, processor 410, and power source 411. Those skilled in the art will appreciate that the electronic device structure shown in fig. 4 is not limiting of the electronic device and that the electronic device may include more or fewer components than shown, or may combine certain components, or a different arrangement of components. In the embodiment of the invention, the electronic equipment comprises, but is not limited to, a mobile phone, a tablet computer, a notebook computer, a palm computer, a vehicle-mounted terminal, a wearable device, a pedometer and the like.

It should be understood that, in the embodiment of the present invention, the radio frequency unit 401 may be used for receiving and transmitting signals during the process of receiving and transmitting information or communication, specifically, receiving downlink data from a base station and then processing the received downlink data by the processor 410; and, the uplink data is transmitted to the base station. Typically, the radio frequency unit 401 includes, but is not limited to, an antenna, at least one amplifier, a transceiver, a coupler, a low noise amplifier, a duplexer, and the like. In addition, the radio frequency unit 401 may also communicate with networks and other devices through a wireless communication system.

The electronic device provides wireless broadband internet access to the user through the network module 402, such as helping the user to send and receive e-mail, browse web pages, and access streaming media, etc.

The audio output unit 403 may convert audio data received by the radio frequency unit 401 or the network module 402 or stored in the memory 409 into an audio signal and output as sound. Also, the audio output unit 403 may also provide audio output (e.g., a call signal reception sound, a message reception sound, etc.) related to a specific function performed by the electronic device 400. The audio output unit 403 includes a speaker, a buzzer, a receiver, and the like.

The input unit 404 is used to receive an audio or video signal. The input unit 404 may include a graphics processor (Graphics Processing Unit, GPU) 4041 and a microphone 4042, the graphics processor 4041 processing image data of still pictures or video obtained by an image capturing device (e.g., a camera) in a video capturing mode or an image capturing mode. The processed image frames may be displayed on the display unit 406. The image frames processed by the graphics processor 4041 may be stored in memory 409 (or other storage medium) or transmitted via the radio frequency unit 401 or the network module 402. The microphone 4042 may receive sound and may be capable of processing such sound into audio data. The processed audio data may be converted into a format output that can be transmitted to the mobile communication base station via the radio frequency unit 401 in the case of a telephone call mode.

The electronic device 400 also includes at least one sensor 405, such as a light sensor, a motion sensor, and other sensors. Specifically, the light sensor includes an ambient light sensor that can adjust the brightness of the display panel 4061 according to the brightness of ambient light, and a proximity sensor that can turn off the display panel 4061 and/or the backlight when the electronic device 400 is moved to the ear. As one of the motion sensors, the accelerometer sensor can detect the acceleration in all directions (generally three axes), and can detect the gravity and direction when stationary, and can be used for recognizing the gesture of the electronic equipment (such as horizontal and vertical screen switching, related games, magnetometer gesture calibration), vibration recognition related functions (such as pedometer and knocking), and the like; the sensor 405 may further include a fingerprint sensor, a pressure sensor, an iris sensor, a molecular sensor, a gyroscope, a barometer, a hygrometer, a thermometer, an infrared sensor, etc., which are not described herein.

The display unit 406 is used to display information input by a user or information provided to the user. The display unit 406 may include a display panel 4061, and the display panel 4061 may be configured in the form of a liquid crystal display (Liquid Crystal Display, LCD), an Organic Light-Emitting Diode (OLED), or the like.

The user input unit 407 may be used to receive input numeric or character information and to generate key signal inputs related to user settings and function control of the electronic device. Specifically, the user input unit 407 includes a touch panel 4071 and other input devices 4072. The touch panel 4071, also referred to as a touch screen, may collect touch operations thereon or thereabout by a user (e.g., operations of the user on the touch panel 4071 or thereabout using any suitable object or accessory such as a finger, stylus, etc.). The touch panel 4071 may include two parts, a touch detection device and a touch controller. The touch detection device detects the touch azimuth of a user, detects a signal brought by touch operation and transmits the signal to the touch controller; the touch controller receives touch information from the touch detection device, converts it into touch point coordinates, and sends the touch point coordinates to the processor 410, and receives and executes commands sent from the processor 410. In addition, the touch panel 4071 may be implemented in various types such as resistive, capacitive, infrared, and surface acoustic wave. The user input unit 407 may include other input devices 4072 in addition to the touch panel 4071. In particular, other input devices 4072 may include, but are not limited to, a physical keyboard, function keys (e.g., volume control keys, switch keys, etc.), a trackball, a mouse, and a joystick, which are not described in detail herein.

Further, the touch panel 4071 may be overlaid on the display panel 4061, and when the touch panel 4071 detects a touch operation thereon or thereabout, the touch operation is transferred to the processor 410 to determine the type of touch event, and then the processor 410 provides a corresponding visual output on the display panel 4061 according to the type of touch event. Although in fig. 4, the touch panel 4071 and the display panel 4061 are two independent components for implementing the input and output functions of the electronic device, in some embodiments, the touch panel 4071 may be integrated with the display panel 4061 to implement the input and output functions of the electronic device, which is not limited herein.

The interface unit 408 is an interface to which an external device is connected to the electronic apparatus 400. For example, the external devices may include a wired or wireless headset port, an external power (or battery charger) port, a wired or wireless data port, a memory card port, a port for connecting a device having an identification module, an audio input/output (I/O) port, a video I/O port, an earphone port, and the like. The interface unit 408 may be used to receive input (e.g., data information, power, etc.) from an external device and transmit the received input to one or more elements within the electronic apparatus 400 or may be used to transmit data between the electronic apparatus 400 and an external device.

Memory 409 may be used to store software programs as well as various data. The memory 409 may mainly include a storage program area that may store an operating system, application programs required for at least one function (such as a sound playing function, an image playing function, etc.), and a storage data area; the storage data area may store data (such as audio data, phonebook, etc.) created according to the use of the handset, etc. In addition, memory 409 may include high-speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other volatile solid-state storage device.

The processor 410 is a control center of the electronic device, connects various parts of the entire electronic device using various interfaces and lines, and performs various functions of the electronic device and processes data by running or executing software programs and/or modules stored in the memory 409 and invoking data stored in the memory 409, thereby performing overall monitoring of the electronic device. Processor 410 may include one or more processing units; preferably, the processor 410 may integrate an application processor that primarily handles operating systems, user interfaces, applications, etc., with a modem processor that primarily handles wireless communications. It will be appreciated that the modem processor described above may not be integrated into the processor 410.

The electronic device 400 may also include a power supply 411 (e.g., a battery) for powering the various components, and preferably the power supply 411 may be logically connected to the processor 410 via a power management system that performs functions such as managing charging, discharging, and power consumption.

In addition, the electronic device 400 includes some functional modules, which are not shown, and are not described herein.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

From the above description of the embodiments, it will be clear to those skilled in the art that the above-described embodiment method may be implemented by means of software plus a necessary general hardware platform, but of course may also be implemented by means of hardware, but in many cases the former is a preferred embodiment. Based on such understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a storage medium (e.g. ROM/RAM, magnetic disk, optical disk) comprising instructions for causing a terminal (which may be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to perform the method according to the embodiments of the present invention.

The embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to the above-described embodiments, which are merely illustrative and not restrictive, and many forms may be made by those having ordinary skill in the art without departing from the spirit of the present invention and the scope of the claims, which are to be protected by the present invention.

Claims

1. A fatigue life analysis method for a coil spring, the coil spring being disposed in a vehicle, the coil spring having corresponding upper and lower bolsters, comprising:

determining the assembly condition and the movement path of the vehicle;

2. The method as recited in claim 1, further comprising:

3. The method of claim 2, wherein the step of determining a fatigue life analysis result for the coil spring by the contact property comprises:

4. A method according to claim 3, wherein the coil springs have corresponding spring trays, the first unit nodes include upper and lower load points, and the step of determining constraint parameters of the three-dimensional model of the coil springs based on the contact properties comprises:

determining the load point as a first master node;

determining the load point as a second master node;

5. The method of claim 4, wherein the step of determining a load boundary condition of the three-dimensional model of the coil spring based on the contact property comprises:

establishing a local coordinate system aiming at the lower load point;

determining a random road load for the local coordinate system;

6. The method of claim 5, wherein the step of determining random road loads for the local coordinate system comprises:

determining a whole vehicle multi-body dynamics model for the vehicle;

and taking the peak value and the trough value as the random road load.

7. A method according to claim 3, further comprising:

determining a stress fatigue curve corresponding to the material property;

8. The method of claim 7, wherein the step of determining a stress fatigue curve corresponding to the material property comprises:

acquiring life parameters and stress ratios for the material properties;

9. The method of claim 7, wherein the step of determining a stress fatigue curve corresponding to the material property comprises:

A stress fatigue curve corresponding to the material property is determined based on the first parameter to be determined, the second parameter to be determined, the ultimate strength and the form factor of action.

10. A fatigue life analysis device for a coil spring, the coil spring being disposed in a vehicle, the coil spring having corresponding upper and lower bolsters, comprising:

11. An electronic device, comprising:

at least one processor; the method comprises the steps of,

a memory communicatively coupled to the at least one processor; wherein,,

the memory stores instructions executable by the at least one processor to enable the at least one processor to implement the fatigue life analysis method for a coil spring of any of claims 1-9.

12. A computer readable storage medium storing a computer program, wherein the computer program when executed by a processor implements the fatigue life analysis method for a coil spring according to any one of claims 1 to 9.