Method and device for evaluating service life of vehicle part on line

Abstract

The invention provides a method and device for evaluating the service life of vehicle parts on line, and the method comprises the steps: determining the real-time load of each chassis part in a suspension system of a vehicle according to the six component forces of the wheel center of the vehicle obtained in the operation process of the vehicle; determining the deformation state of each chassis part according to the wheel center six-component force and the real-time load and the strength bearing capacity load of each chassis part; based on the deformation state, the real-time load and the pseudo damage cardinal number of each chassis part, determining the residual life of each chassis part; according to the deformation state and the remaining life of each chassis part, the corresponding chassis part state notice is sent in combination with the wheel center six-component force and the preset driver impact feeling threshold value, accurate graded quantitative evaluation of the deformation state and the remaining life of the vehicle chassis part is achieved, and real-time state notice is carried out. The misdiagnosis and missed diagnosis of the states of the parts of the chassis in the driving process can be avoided, and the driving safety is guaranteed.

Description

Technical Field

[0001] The present application relates to the field of vehicle engineering technology, and in particular to a method and device for online evaluation of the life of vehicle parts. Background Art

[0002] As load-bearing parts, the life of vehicle chassis components directly affects the safety performance of the vehicle. During the vehicle development stage, chassis components are usually rigorously analyzed and verified through data analysis, simulation, real vehicle testing, and user research.

[0003] The actual use environment of vehicles is complex and changeable, including many factors such as user driving habits and road conditions. Some extreme conditions will have a significant impact on the life of chassis components, and thus affect driving safety. For example, sudden potholes, sharp turns or emergency braking often bring great impact to vehicle chassis components.

[0004] In the prior art, drivers can only rely on their own subjective feelings to judge the severity of the impact, and cannot quantify the specific damage caused by these impacts to the chassis parts. However, this judgment often has errors. When the driver subjectively feels a large impact, if the actual damage does not exceed the tolerance of the chassis parts, then frequent visits to the maintenance center for inspection will not only consume a lot of manpower and material resources, but may also cause unnecessary panic. On the contrary, if the actual impact is large but the driver fails to notice it in time, the damage to the chassis parts may gradually accumulate, eventually leading to serious safety problems, such as vehicle loss of control, component breakage, etc., posing a serious threat to the life safety of the driver and passengers. Summary of the invention

[0005] The present application provides a method and device for online evaluation of the life of vehicle components, which realizes accurate quantitative evaluation of the deformation state and remaining life of vehicle chassis components and performs status notification, thereby avoiding misdiagnosis and missed diagnosis of component status during driving and ensuring driving safety.

[0006] In a first aspect, an embodiment of the present application provides a method for online evaluation of the life of vehicle components, the method comprising: Acquiring the six-component force of the wheel center of the vehicle during the operation of the vehicle, and determining the real-time load of each chassis component in the suspension system of the vehicle according to the six-component force of the wheel center; Determine the deformation state of each chassis component according to the six components of the wheel center, the real-time load of each chassis component and the strength bearing capacity load of each chassis component; Based on the deformation state of each chassis component, the remaining life of each chassis component is determined according to the real-time load of each chassis component and the pseudo-damage base of each chassis component; According to the deformation state and remaining life of each chassis component, combined with the six-component wheel center force and the preset driver impact perception threshold, a corresponding chassis component status notification is issued.

[0007] In combination with the first aspect, in one implementation, obtaining six components of wheel center force of the vehicle during vehicle operation includes: The six-component force of the wheel center of the vehicle is calculated according to the unsprung acceleration, the sprung acceleration and the sprung and unsprung relative compression displacement of the vehicle collected during the operation of the vehicle.

[0008] In combination with the first aspect, in one implementation manner, calculating the six-component wheel center force of the vehicle according to the unsprung acceleration, the sprung acceleration, and the sprung and unsprung relative compression displacement of the vehicle collected during the operation of the vehicle includes: The wheel center normal force of the vehicle is calculated according to the vertical stiffness of the suspension system, the relative compression displacement between the sprung and unsprung parts, the vertical damping coefficient of the suspension system, the relative compression velocity between the sprung and unsprung parts, the unsprung mass of the vehicle, and the unsprung vertical acceleration; The wheel center braking torque is calculated according to the brake hydraulic line pressure of the vehicle, the area of ​​the brake wheel cylinder piston, and the radius from the brake wheel cylinder piston to the wheel axle; When the unsprung vertical acceleration is greater than or equal to a preset first acceleration threshold, or the sprung vertical acceleration is greater than or equal to a preset second acceleration threshold, the wheel center longitudinal force of the vehicle is calculated based on the unsprung mass, the unsprung longitudinal acceleration, the longitudinal stiffness of the suspension system, and the longitudinal displacement of the unsprung mass relative to the sprung mass; When the unsprung vertical acceleration is less than a preset first acceleration threshold and the sprung vertical acceleration is less than a preset second acceleration threshold, if the vehicle is in an accelerating state, the longitudinal moment of the entire vehicle is determined according to the sprung longitudinal acceleration, and the wheel center longitudinal force of the vehicle is obtained according to the longitudinal moment of the entire vehicle; if the vehicle is in a braking state, the wheel center longitudinal force of the vehicle is calculated according to the wheel center braking moment and the wheel rolling radius of the vehicle; Calculating the wheel center lateral force of the vehicle according to the overall mass of the front axle of the vehicle and the lateral acceleration of the front axle; The wheel center turning moment is calculated based on the wheel center lateral force, the wheel rolling radius, and the distance between the wheel lateral force point and the wheel center; The wheel center aligning torque is calculated based on the axial force of the steering tie rod of the vehicle and the action distance between the steering tie rod ball pin action point and the kingpin.

[0009] In combination with the first aspect, in one implementation, before determining the deformation state of each chassis component according to the six wheel center forces, the real-time load of each chassis component and the strength bearing capacity load of each chassis component, the method further includes: Obtaining the strength bearing capacity loads of each chassis component in each direction during the bench strength test, wherein the strength bearing capacity loads include the yield point load and the equivalent plastic strain PEEQ2% point load, as well as the large deformation point load or the fracture point load; For each load value after the yield point load and before the large deformation point load or the fracture point load in each direction of each chassis component, a corresponding mapping relationship is constructed in combination with the corresponding equivalent plastic strain; The strength bearing capacity loads of each chassis component in each direction are converted into corresponding converted wheel center loads, and the yield point converted wheel center loads and PEEQ2% point converted wheel center loads in each direction of each chassis component, as well as the large deformation point converted wheel center loads or the fracture point converted wheel center loads are obtained.

[0010] In combination with the first aspect, in one implementation, the deformation state of each chassis component is determined according to the six wheel center forces, the real-time load of each chassis component and the strength bearing capacity load of each chassis component, including: For any chassis component, when the six components of the wheel center force are all less than or equal to the wheel center load converted from the yield point in each direction of the chassis component, it is determined that the deformation state of the chassis component is that no equivalent plastic strain occurs; When the six wheel center forces are greater than the wheel center load converted from the yield point in any direction of the chassis component, and are less than or equal to the wheel center load converted from the PEEQ2% point in each direction, it is determined that the chassis component has a first-order equivalent plastic strain, and the mapping relationship is searched according to the real-time load of the chassis component to obtain the maximum equivalent plastic strain of the chassis component; When the six wheel center forces are greater than the wheel center load converted from the PEEQ2% point in any direction of the chassis component, and are all less than the wheel center load converted from the large deformation point in each direction or the wheel center load converted from the fracture point, it is determined that the chassis component has a secondary equivalent plastic strain, and the mapping relationship is searched according to the real-time load of the chassis component to obtain the maximum equivalent plastic strain of the chassis component; When the six wheel center forces are greater than or equal to the maximum deformation point-converted wheel center load or the fracture point-converted wheel center load in any direction of the chassis component, it is determined that the chassis component has undergone a large deformation or has fractured.

[0011] In combination with the first aspect, in one embodiment, before determining the remaining life of each chassis component based on the deformation state of each chassis component, according to the real-time load of each chassis component and the pseudo damage base of each chassis component, the method further includes: When the vehicle is subjected to a proving ground durability test, pseudo damage of Q times the proving ground durability load in each direction of each chassis component is used as the pseudo damage base of the corresponding chassis component in each direction.

[0012] In combination with the first aspect, in one implementation, the determining the remaining life of each chassis component based on the deformation state of each chassis component, according to the real-time load of each chassis component and the pseudo damage base of each chassis component, includes: For any chassis component, when the chassis component does not have equivalent plastic strain, the accumulated pseudo damage of the chassis component in each direction is calculated in real time by the rain flow counting algorithm according to the six-component force of the wheel center, and the accumulated pseudo damage of the chassis component in each direction is divided by the pseudo damage base in the corresponding direction to obtain the service life in each direction, and the remaining service life of the chassis component is determined according to the maximum service life; When the deformation state of the chassis component is the first-level equivalent plastic strain or the second-level equivalent plastic strain, the impact load damage of the chassis component is calculated according to the material type and the maximum equivalent plastic strain of the component, and the damage life and the remaining life of the chassis component are obtained according to the impact load damage and the pseudo damage cardinality in the corresponding direction; When the deformation state of the chassis component is large deformation or fracture, it is determined that the remaining life of the chassis component is zero.

[0013] In combination with the first aspect, in one implementation, the corresponding chassis component status notification is issued according to the deformation state and the remaining life of each chassis component, in combination with the six-component force of the wheel center and a preset driver impact perception threshold, including: When all chassis components of the suspension system do not have plastic strain, if the wheel center longitudinal force is greater than the driver's longitudinal impact perception threshold, the wheel center lateral force is greater than the driver's lateral impact perception threshold, or the wheel center normal force is greater than the driver's normal impact perception threshold, a first status notification indicating that the chassis components are not damaged is issued, otherwise, no status notification is issued; When a chassis component has a first-level equivalent plastic strain, a second status notification for indicating that the chassis component has a first-level equivalent plastic strain is issued, and the chassis component having the first-level equivalent plastic strain and its remaining life are simultaneously displayed; When a chassis component has secondary equivalent plastic strain, a third state notification is issued to indicate that the chassis component has secondary equivalent plastic strain and that the vehicle needs to be driven with caution, and the chassis component having secondary equivalent plastic strain and its remaining life are simultaneously displayed; When there is a chassis component that is greatly deformed or broken, a fourth status notification is issued to indicate that the chassis component is greatly deformed or broken and safe driving is impossible, and the greatly deformed or broken chassis component is displayed synchronously, and the chassis component status is sent to the after-sales service end.

[0014] In conjunction with the first aspect, in one implementation: The driver's longitudinal impact perception threshold is M times the maximum wheel load that the vehicle can bear; The driver's lateral impact perception threshold is N times the maximum wheel load that the vehicle can bear; The driver's normal impact perception threshold is R times the maximum wheel load that the vehicle can bear.

[0015] In a second aspect, an embodiment of the present application provides a device for online evaluation of the life of vehicle parts, the device for online evaluation of the life of vehicle parts comprising: An acquisition module, which is used to acquire the six-component wheel center force of the vehicle during the operation of the vehicle, and determine the real-time load of each chassis component in the suspension system of the vehicle according to the six-component wheel center force; A first determination module, which is used to determine the deformation state of each chassis component according to the six components of the wheel center, the real-time load of each chassis component and the strength bearing capacity load of each chassis component; A second determination module is used to determine the remaining life of each chassis component based on the deformation state of each chassis component, according to the real-time load of each chassis component and the pseudo damage base of each chassis component; The notification module is used to issue corresponding chassis component status notifications according to the deformation status and remaining life of each chassis component, combined with the six-component force of the wheel center and a preset driver impact perception threshold.

[0016] The beneficial effects brought by the technical solution provided in the embodiments of the present application include: The six wheel center forces of the vehicle are obtained during the operation of the vehicle, and the real-time loads of the chassis components in the suspension system of the vehicle are determined according to the six wheel center forces; the deformation state of each chassis component is determined according to the six wheel center forces, the real-time loads of each chassis component and the strength bearing capacity load of each chassis component; based on the deformation state of each chassis component, the remaining life of each chassis component is determined according to the real-time load of each chassis component and the pseudo-damage base of each chassis component; according to the deformation state and the remaining life of each chassis component, the corresponding chassis component status notification is issued in combination with the six wheel center forces and the preset driver impact perception threshold, thereby realizing accurate graded quantitative evaluation of the deformation state and the remaining life of the vehicle chassis components and performing real-time status notification, which can avoid misdiagnosis and missed diagnosis of the status of chassis components during driving, ensure driving safety, and reduce the panic of drivers when the vehicle passes through complex road conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of a flow chart of an embodiment of a method for online evaluation of vehicle component life in the present application; Figure 2 It is a schematic diagram of load distribution of chassis components’ strength bearing capacity; Figure 3 This is a schematic diagram of pseudo-damage distribution of chassis components’ durable load-bearing capacity; Figure 4 This is a schematic diagram of the functional modules of an embodiment of a device for online evaluation of vehicle parts life in the present application. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0019] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0020] In a first aspect, an embodiment of the present application provides a method for online evaluation of the life of vehicle components.

[0021] In one embodiment, referring to Figure 1 , Figure 1 This is a flow chart of the first embodiment of the method for online evaluation of vehicle parts life in this application. Figure 1As shown, the methods for online assessment of vehicle component life include: Step S101, obtaining the six-component wheel center force of the vehicle during vehicle operation, and determining the real-time load of each chassis component in the suspension system of the vehicle according to the six-component wheel center force.

[0022] Step S102: determining the deformation state of each chassis component according to the six components of the wheel center force, the real-time load of each chassis component and the strength bearing capacity load of each chassis component.

[0023] Step S103: Based on the deformation state of each chassis component, according to the real-time load of each chassis component and the pseudo damage base of each chassis component, the remaining life of each chassis component is determined.

[0024] Step S104: issuing a corresponding chassis component status notification according to the deformation status and remaining life of each chassis component, in combination with the six-component wheel center force and a preset driver impact perception threshold.

[0025] It is worth noting that the present embodiment obtains the wheel center stress conditions of the vehicle online to quantitatively calculate the deformation state and the remaining life of each chassis component in real time, and notifies the chassis component status in real time, which can help the driver to know the accurate status of the vehicle components in time, avoid misdiagnosis and missed diagnosis of the chassis component status during driving, ensure driving safety, and at the same time reduce the panic of the driver when the vehicle passes through complex road conditions and feels a greater impact subjectively.

[0026] The method for online evaluation of vehicle component life in this application can be applied to different chassis components of different types of suspension systems. Taking the double wishbone front suspension as an example, its chassis components include steering knuckle, lower swing arm, upper swing arm and subframe.

[0027] It is worth noting that the strength bearing capacity load of each chassis component and the pseudo damage base of each chassis component are pre-acquired and pre-set in the vehicle's computing module. The following is an explanation of the method for acquiring the strength bearing capacity load and pseudo damage base of each component.

[0028] In one embodiment, obtaining the strength bearing capacity load of each chassis component specifically includes the following steps: Step S201, obtaining the strength bearing capacity load of each chassis component in each direction in the bench strength test, wherein the strength bearing capacity load includes the yield point load and the equivalent plastic strain PEEQ2% point load, as well as the large deformation point load or the fracture point load.

[0029] For example, a bench test can be performed on each chassis component, or a CAE simulation can be performed on the vehicle to obtain a force-displacement curve from loading to failure in each force direction of each chassis component, the horizontal axis of which is the deformation of the chassis component, and the vertical axis is the load loaded on the chassis component. From the force-displacement curve, the strength bearing capacity load of the corresponding direction of the corresponding chassis component can be obtained. Figure 2 As shown, each direction of each chassis component has a corresponding yield point load and PEEQ=2% point load, as well as a large deformation point load or a breaking point load.

[0030] Taking the swing arm of the following chassis components as an example, the yield point load and PEEQ=2% point load in the X direction, Y direction, and Z direction of the lower swing arm ball head, as well as the maximum deformation point load or the breaking point load are shown in Table 1: Table 1 Strength bearing capacity load of lower swing arm in each direction

[0031] Step S202: for each load value after the yield point load and before the large deformation point load or the fracture point load in each direction of each chassis component, a corresponding mapping relationship is constructed in combination with the corresponding equivalent plastic strain.

[0032] It is worth noting that before the yield point load, the deformation of chassis parts is elastic deformation, and they can return to their original shape after the load applied to them is removed. When chassis parts exceed the yield point, before fracture or large deformation occurs, any load value can correspond to an equivalent plastic strain. Therefore, a mapping relationship between each load value after the yield point load and before the large deformation point load or the fracture point load and the corresponding equivalent plastic strain can be constructed.

[0033] Step S203: Through the pre-established vehicle dynamics multi-body model, according to the corresponding conversion coefficient, the strength bearing capacity loads of each chassis component in each direction can be converted into corresponding converted wheel center loads, thereby obtaining the yield point converted wheel center loads and PEEQ2% point converted wheel center loads of each chassis component in each direction, as well as the large deformation point converted wheel center loads or the fracture point converted wheel center loads. The conversion method of converting the strength bearing capacity load into the wheel center load has been recorded in the relevant public technology and will not be repeated here.

[0034] Furthermore, obtaining the strength bearing capacity load of each chassis component specifically includes the following steps: When the vehicle is subjected to a proving ground durability test, pseudo damage of Q times the proving ground durability load in each direction of each chassis component is used as the pseudo damage base of the corresponding chassis component in each direction.

[0035] Explanatory, the relative relationship between the chassis component load-bearing capacity pseudo-damage and the test field endurance load pseudo-damage is as follows Figure 3 As shown. Usually, the life of chassis components is at least 4 times the life of the endurance test in the test field. After counting the pseudo damage of the endurance wheel center load in the test field, due to the inconsistency of the environment (high temperature, corrosion) when users use the vehicle, in order to facilitate calculation, in this embodiment, the life of each component is normalized to define 1 times the life of the test field, and the point where the load reaches this point is used as a user must check point to ensure driving safety.

[0036] For example, in this embodiment, the pseudo damage of 1 times the test field endurance load in each direction of each chassis component is used as the pseudo damage base number of each direction of the corresponding chassis component. The pseudo damage base numbers of the lower arm in each direction are shown in Table 2: Table 2 Pseudo-damage base number of lower arm in each direction

[0037] As a preferred implementation, the driver's impact perception threshold is also pre-set in the vehicle's computing module, and the driver's impact perception threshold includes the driver's impact longitudinal perception threshold, the driver's impact lateral perception threshold and the driver's impact normal perception threshold.

[0038] The driver's longitudinal impact perception threshold is M times the vehicle's maximum wheel load; the driver's lateral impact perception threshold is N times the vehicle's maximum wheel load; and the driver's normal impact perception threshold is R times the vehicle's maximum wheel load.

[0039] For example, in this embodiment, the driver's longitudinal impact perception threshold is 2 times the maximum wheel load that the vehicle can carry, the driver's lateral impact perception threshold is 1.5 times the maximum wheel load that the vehicle can carry, and the driver's normal impact perception threshold is 2 times the maximum wheel load that the vehicle can carry. The driver's impact perception threshold here is used to simulate the driver's subjective feeling that passing a pothole is the threshold point for thinking that "the vehicle has been damaged and needs to be stopped for inspection or after-sales inspection."

[0040] After the strength bearing capacity load, pseudo-damage base number and driver impact perception threshold of chassis components are preset in the vehicle calculation module, the life of vehicle chassis components can be evaluated online.

[0041] It is worth noting that when obtaining the six-component wheel center force of the vehicle during the operation of the vehicle in step S101, since the user's vehicle cannot use various special sensors for the six-component wheel center force to collect the six-component wheel center force like the test vehicle, this embodiment uses a series of vehicle-mounted sensors to collect some physical quantities in real time and then calculate the wheel center force through conversion and estimation.

[0042] In one embodiment, the six-component wheel center force of the vehicle is calculated based on the unsprung acceleration, the sprung acceleration, and the sprung and unsprung relative compression displacement of the vehicle collected during the operation of the vehicle.

[0043] Among them, the six wheel center forces include: wheel center longitudinal force Fx, wheel center lateral force Fy, wheel center normal force Fz, wheel center overturning moment Mx, wheel center braking moment My and wheel center self-aligning moment Mz. The sprung part of the vehicle refers to the part supported by the suspension system, including the body, frame, power system, etc., and the unsprung part refers to the part not supported by the suspension system, including suspension, wheels and braking system, etc.

[0044] The unsprung acceleration collected in this embodiment includes the unsprung longitudinal (X-direction) acceleration ax1, the unsprung lateral (Y-direction) acceleration ay1 and the unsprung vertical (Z-direction) acceleration az1; the sprung acceleration includes the sprung longitudinal acceleration ax2, the sprung lateral acceleration ay2 and the sprung vertical acceleration az2. The sprung-unsprung relative compression displacement is the sprung-unsprung relative compression displacement measured in real time by the height sensor.

[0045] Specifically, the wheel center normal force of the vehicle is calculated based on the vertical stiffness of the suspension system, the relative compression displacement between the sprung and unsprung wheels, the vertical damping coefficient of the suspension system, the relative compression velocity between the sprung and unsprung wheels, the unsprung mass of the vehicle, and the unsprung vertical acceleration: Fz=Kz*h+Dz* h′+M1*az1 Wherein, Fz is the wheel center normal force, Kz is the vertical stiffness of the suspension system, h is the relative compression displacement between the sprung and unsprung components, Dz is the vertical damping coefficient of the suspension system, h′ is the time derivative of the relative compression displacement h between the sprung and unsprung components, i.e., the relative compression velocity between the sprung and unsprung components, M1 is the unsprung mass of the vehicle, and az1 is the unsprung vertical acceleration.

[0046] Among them, unsprung mass refers to the mass that is not supported by the suspension system, usually including wheels, tires, braking systems (such as brake discs, brake calipers) and suspension components (such as springs, shock absorbers, connecting rods, etc.). The vertical stiffness Kz of the suspension system needs to be obtained in advance through bench tests or simulations. It is worth noting that it is not just the stiffness of the linear segment. This case definition requires that the force be loaded until the entire suspension system fails, and the force-displacement curve at this time is recorded as the stiffness curve. Generally, the greater the force, the more obvious the nonlinearity.

[0047] Furthermore, the brake hydraulic line pressure of the vehicle is collected, and the wheel center braking torque is calculated according to the brake hydraulic line pressure of the vehicle, the area of ​​the brake wheel cylinder piston, and the radius from the brake wheel cylinder piston to the wheel axle: My=2*P*s*r Where P is the vehicle's brake hydraulic line pressure, s is the wheel cylinder piston area, and r is the radius from the wheel cylinder piston to the wheel axle.

[0048] Explanatory, when the vehicle brakes, the braking torque is loaded onto the suspension, and the suspension force needs to be re-added with the braking torque. Since the reaction force of the driving torque is transmitted by the wheel-drive shaft-motor-body, the driving torque is ignored when calculating the suspension. That is, only when braking is applied, regardless of whether there is an impact on the road surface, the torque in the direction of My is transmitted to the suspension only if the brake provides My.

[0049] Furthermore, when the unsprung vertical acceleration is greater than or equal to a preset first acceleration threshold, or the sprung vertical acceleration is greater than or equal to a preset second acceleration threshold, the wheel center longitudinal force of the vehicle is calculated based on the unsprung mass, the unsprung longitudinal acceleration, the longitudinal stiffness of the suspension system, and the longitudinal displacement of the unsprung mass relative to the sprung mass.

[0050] For example, in this embodiment, the first acceleration threshold is 5g, the acceleration threshold is 0.5g, and g is the acceleration due to gravity. That is, when az1≥5g or az2≥0.5g, the longitudinal force of the wheel center of the vehicle is calculated based on the unsprung mass, the unsprung longitudinal acceleration, the longitudinal stiffness of the suspension system, and the longitudinal displacement of the unsprung relative to the sprung mass: Fx=M1*ax1+Kx*Disp_X Where Fx is the longitudinal force of the wheel center, M1 is the unsprung mass, ax1 is the unsprung longitudinal acceleration, Kx is the longitudinal stiffness of the suspension system, and Disp_X is the longitudinal displacement of the unsprung relative to the sprung mass.

[0051] Among them, the 50hz low-pass filter of the unsprung and sprung longitudinal accelerations can be integrated to obtain the velocity, and then the displacement can be obtained by integrating again. The displacement difference between the two is the longitudinal (X-direction) displacement Disp_X of the unsprung mass relative to the sprung mass. The longitudinal stiffness Kx of the suspension system needs to be obtained by bench testing or simulation. It is worth noting that it is not just the stiffness of the linear segment. This case definition requires that the force be loaded until the entire suspension system fails, and the force-displacement curve at this time is recorded as the stiffness curve. Generally, the greater the force, the more obvious the nonlinearity.

[0052] When the unsprung vertical acceleration is less than a preset first acceleration threshold and the sprung vertical acceleration is less than a preset second acceleration threshold, if the vehicle is in an acceleration state, the longitudinal moment of the entire vehicle is determined according to the sprung longitudinal acceleration, and the wheel center longitudinal force of the vehicle is obtained according to the longitudinal moment of the entire vehicle; if the vehicle is in a braking state, the wheel center longitudinal force of the vehicle is calculated according to the wheel center braking torque and the wheel rolling radius of the vehicle.

[0053] Exemplarily, when az1<5g and az2<0.5g and the vehicle accelerates, the longitudinal moment of the vehicle is calculated based on the sprung longitudinal acceleration, and the longitudinal moment of the vehicle is distributed to the four wheels according to the front and rear torque distribution ratio, thereby obtaining the wheel center longitudinal force of the vehicle.

[0054] When az1<5g and az2<0.5g and the vehicle brakes, the wheel center braking torque is divided by the wheel rolling radius of the vehicle to obtain the wheel center longitudinal force of the vehicle.

[0055] Furthermore, since the lateral (Y-direction) stiffness of the vehicle suspension is very large, the wheel center lateral force of the vehicle is calculated based on the overall mass of the front axle and the lateral acceleration of the front axle. FY =(M_front)*ay_front Among them, M_front is the overall mass of the vehicle's front axle, and ay_front is the lateral acceleration of the vehicle's front axle.

[0056] Furthermore, the distance between the lateral force point of the wheel (Y direction) and the wheel center is uniformly set as the rolling radius - 100mm as the loading point. According to the wheel center lateral force, the wheel rolling radius, and the distance between the lateral force point of the wheel and the wheel center, the wheel center overturning torque is calculated: Mx=Fy*(rolling radius-100mm) Where Mx is the wheel center turning moment, and Fy is the wheel center lateral force.

[0057] Furthermore, the wheel center aligning torque is calculated based on the axial force of the steering tie rod of the vehicle and the distance between the steering tie rod ball pin action point and the kingpin: Mz=F*L Among them, Mz is the wheel center self-aligning torque, F is the axial force of the vehicle's steering rod, and L is the distance between the steering rod ball pin action point and the kingpin.

[0058] The six-component wheel center force is obtained through the above method, and through the pre-defined multi-body model, the obtained six-component wheel center force can be converted into real-time loads in various directions of various chassis components in the suspension system in real time, so that the force-time domain curves in various directions of each chassis component can be obtained. The specific conversion method will not be repeated here.

[0059] In one embodiment, in step S102, the deformation state of each chassis component is determined according to the six components of the wheel center force, the real-time load of each chassis component, and the strength bearing capacity load of each chassis component, which specifically includes: Step S1021: For any chassis component, when the six wheel center forces are all less than or equal to the wheel center load converted from the yield point in each direction of the chassis component, it is determined that the deformation state of the chassis component is that no equivalent plastic strain occurs.

[0060] Step S1022: When the six wheel center force components are greater than the yield point converted wheel center load in any direction of the chassis component, and are less than or equal to the PEEQ2% point converted wheel center load in each direction, it is determined that the chassis component has a first-order equivalent plastic strain, and the mapping relationship is searched according to the real-time load of the chassis component to obtain the maximum equivalent plastic strain of the chassis component.

[0061] Explanatory, the six-component force of the wheel center may be greater than the yield point-converted wheel center load of the chassis component in multiple directions (taking two directions as an example), and the mapping relationship of the corresponding directions is found according to the real-time loads in these two directions, and the equivalent plastic strain corresponding to the real-time loads in the two directions is obtained, and the maximum equivalent plastic strain of the two is determined as the final equivalent plastic strain of the chassis component.

[0062] Step S1023: When the six wheel center forces are greater than the wheel center load converted from the PEEQ2% point in any direction of the chassis component, and are all smaller than the wheel center load converted from the largest deformation point in each direction or the wheel center load converted from the fracture point, it is determined that the chassis component has a secondary equivalent plastic strain, and the mapping relationship is searched according to the real-time load of the chassis component to obtain the maximum equivalent plastic strain of the chassis component.

[0063] The method for determining the maximum equivalent plastic strain here is the same as above and will not be repeated here.

[0064] Step S1024: When the six wheel center forces are greater than or equal to the maximum deformation point-converted wheel center load or the fracture point-converted wheel center load in any direction of the chassis component, it is determined that the chassis component has been greatly deformed or fractured.

[0065] In one embodiment, in step S103, based on the deformation state of each chassis component, according to the real-time load of each chassis component and the pseudo damage base of each chassis component, the remaining life of each chassis component is determined, specifically including: Step S1031: For any chassis component, when the chassis component does not have equivalent plastic strain, the cumulative pseudo-damage of the chassis component in each direction is calculated in real time by a rain flow counting algorithm according to the six-component force of the wheel center, and the cumulative pseudo-damage of the chassis component in each direction is divided by the pseudo-damage base in the corresponding direction to obtain the service life in each direction, and the remaining service life of the chassis component is determined according to the maximum service life.

[0066] For example, when a chassis component does not have equivalent plastic strain, the accumulated pseudo-damage in each direction is directly calculated in real time through rain flow counting. Taking the lower swing arm as an example, the accumulated pseudo-damage in each direction is shown in Table 3. Divide the accumulated pseudo-damage in each direction by the pseudo-damage base number in each direction pre-defined in Table 2 to obtain the relative proportion of pseudo-damage in each direction as the service life in each direction. Extract the maximum service life. For example, extract 10% of the relative proportion of the wheel center in the Z direction as the maximum service life in Table 3, and calculate the remaining service life of the lower swing arm as 1-10%=90%.

[0067] Table 3 Accumulated pseudo damage and relative proportion of lower arm in each direction

[0068] Step S1032: When the deformation state of the chassis component is the first-level equivalent plastic strain or the second-level equivalent plastic strain, the impact load damage of the chassis component is calculated according to the material type and the maximum equivalent plastic strain of the component, and the damage life and the remaining life of the chassis component are obtained according to the impact load damage and the pseudo-damage cardinality in the corresponding direction.

[0069] Exemplarily, when the deformation state of the chassis component is the first-level equivalent plastic strain or the second-level equivalent plastic strain, and the material of the chassis component is an aluminum alloy material, the impact load damage is calculated according to the following formula: Damage=2 / (10^log10(W) / 0.35) / (-0.69) Among them, Damage is the impact load damage, and W is the maximum equivalent plastic strain of the component.

[0070] When the chassis component is made of steel, the impact load damage is calculated according to the following formula: Damage=2 / (10^log10(W) / 0.59) / (-0.58) Among them, Damage is the impact load damage, and W is the maximum equivalent plastic strain of the component.

[0071] The damage life of the chassis component is = (Damage / pseudo-damage base in the corresponding direction) * 100%. At this time, the remaining life of the chassis component = the remaining life of the chassis component when no equivalent plastic strain occurs - the damage life of the chassis component.

[0072] Step S1033: When the deformation state of the chassis component is large deformation or fracture, determine that the remaining life of the chassis component is zero.

[0073] In one embodiment, step S104 issues a corresponding chassis component status notification based on the deformation state and remaining life of each chassis component, combined with the six-component wheel center force and a preset driver impact perception threshold, specifically including: Step S1041: When all chassis components in the suspension system have not undergone plastic strain, if the wheel center longitudinal force is greater than the driver's longitudinal impact perception threshold, the wheel center lateral force is greater than the driver's lateral impact perception threshold, or the wheel center normal force is greater than the driver's normal impact perception threshold, a first status notification is issued to indicate that the chassis components are not damaged; otherwise, no status notification is issued.

[0074] Explanatory, in this implementation, the driver's impact perception threshold is set to simulate the driver's subjective perception that passing a pothole is the threshold point for thinking that "the vehicle has been damaged and needs to be stopped for inspection or after-sales inspection." When the wheel center force is greater than the driver's impact perception threshold, the user may feel that the driving situation is bad and is worried about the state of the vehicle chassis. At this time, the various chassis components have not exceeded the yield point, and the damage of a single impact is still relatively small. The first status notification indicating that the chassis components are not damaged can be issued through central control notification or voice prompts, thereby alleviating the driver's panic. When the wheel center force does not exceed the driver's impact perception threshold, it means that the current impact does not cause panic to the driver, so there will be no status notification, allowing the driver to focus on driving.

[0075] Step S1042: When a chassis component has first-level equivalent plastic strain, a second status notification is issued to indicate that the chassis component has first-level equivalent plastic strain, and the chassis component having first-level equivalent plastic strain and its remaining life are simultaneously displayed.

[0076] Explanatory, taking the chassis component of the lower arm aluminum part as an example, its life will be greatly reduced after it bears the yield point load 4000 times. Then when the load reaches the load corresponding to PEEQ2%, it can only withstand about 15 impacts, and the life will be seriously reduced. However, as a point that has been considered during the design, when the deformation of the chassis components is between the yield point and the PEEQ2% point, it does not affect normal driving. At this time, the driver is reminded that although the impact load is large, although the damage life value is large this time, (Damage / 1)*100%, but the design has been considered, prompting careful driving, and simultaneously displaying the chassis components that are slightly damaged. At this time, the chassis components have a small plastic deformation, but the impact on driving is small, and the remaining life is displayed simultaneously.

[0077] Step S1043: When a chassis component has secondary equivalent plastic strain, a third state notification is issued to indicate that the chassis component has secondary equivalent plastic strain and the driver needs to drive carefully, and the chassis component having secondary equivalent plastic strain and its remaining life are simultaneously displayed.

[0078] For example, when the real-time calculated wheel center load is greater than the PEEQ2% point of the chassis component and less than the maximum deformation point or the fracture limit point, the chassis component is close to the cracking limit, or a component has undergone a large deformation (the driver can clearly feel the abnormality), the central control directly warns the driver to be careful of vehicle damage, operate safely, and drive slowly to the nearest after-sales point for inspection.

[0079] Step S1044: When a chassis component is greatly deformed or broken, a fourth status notification is issued to indicate that the chassis component is greatly deformed or broken and cannot be driven safely, and the greatly deformed or broken chassis component is displayed synchronously, and the chassis component status is sent to the after-sales service.

[0080] It is worth noting that when the deformation of chassis parts exceeds the fracture limit and the vehicle cannot continue to drive safely, the driver can clearly feel the abnormality. After-sales service will promptly follow up to understand the driver's safety status and ask if any help is needed, such as a tow truck.

[0081] The method for online evaluation of the life of vehicle parts provided in the embodiment of the present application realizes the transformation from traditional subjective judgment to objective data judgment by quantitatively calculating the damage of chassis parts and performing classification. The method can accurately evaluate the damage state of chassis parts according to the force applied during the actual operation of the vehicle, and remind the driver whether inspection and treatment are needed according to the degree of damage. This not only avoids misdiagnosis and missed diagnosis that may occur during driving, but also significantly improves driving safety, while reducing the panic of drivers when the vehicle passes through complex road conditions. The method also has the function of real-time calculation and display of the remaining life percentage of chassis parts, which can help users determine at any time whether maintenance or replacement of chassis parts is needed, thereby improving the service life and reliability of parts.

[0082] In a second aspect, an embodiment of the present application also provides a device for online evaluation of the life of vehicle components.

[0083] In one embodiment, referring to Figure 4 , Figure 4 This is a functional module diagram of an embodiment of the device for online evaluation of vehicle parts life in this application. Figure 4 As shown, the device for online evaluation of vehicle component life includes: An acquisition module, which is used to acquire the six-component wheel center force of the vehicle during the operation of the vehicle, and determine the real-time load of each chassis component in the suspension system of the vehicle according to the six-component wheel center force; A first determination module, which is used to determine the deformation state of each chassis component according to the six components of the wheel center, the real-time load of each chassis component and the strength bearing capacity load of each chassis component; A second determination module is used to determine the remaining life of each chassis component based on the deformation state of each chassis component, according to the real-time load of each chassis component and the pseudo damage base of each chassis component; A notification module is used to issue a corresponding chassis component status notification based on the deformation state and remaining life of each chassis component, combined with the six-component wheel center force and a preset driver impact perception threshold. Further, in one embodiment, the acquisition module is also used to: The six-component force of the wheel center of the vehicle is calculated according to the unsprung acceleration, the sprung acceleration and the sprung and unsprung relative compression displacement of the vehicle collected during the operation of the vehicle.

[0084] Furthermore, in one embodiment, the acquisition module is further used for: The wheel center normal force of the vehicle is calculated according to the vertical stiffness of the suspension system, the relative compression displacement between the sprung and unsprung parts, the vertical damping coefficient of the suspension system, the relative compression velocity between the sprung and unsprung parts, the unsprung mass of the vehicle, and the unsprung vertical acceleration; The wheel center braking torque is calculated according to the brake hydraulic line pressure of the vehicle, the area of ​​the brake wheel cylinder piston, and the radius from the brake wheel cylinder piston to the wheel axle; When the unsprung vertical acceleration is greater than or equal to a preset first acceleration threshold, or the sprung vertical acceleration is greater than or equal to a preset second acceleration threshold, the wheel center longitudinal force of the vehicle is calculated based on the unsprung mass, the unsprung longitudinal acceleration, the longitudinal stiffness of the suspension system, and the longitudinal displacement of the unsprung mass relative to the sprung mass; When the unsprung vertical acceleration is less than a preset first acceleration threshold and the sprung vertical acceleration is less than a preset second acceleration threshold, if the vehicle is in an accelerating state, the longitudinal moment of the entire vehicle is determined according to the sprung longitudinal acceleration, and the wheel center longitudinal force of the vehicle is obtained according to the longitudinal moment of the entire vehicle; if the vehicle is in a braking state, the wheel center longitudinal force of the vehicle is calculated according to the wheel center braking moment and the wheel rolling radius of the vehicle; Calculating the wheel center lateral force of the vehicle according to the overall mass of the front axle of the vehicle and the lateral acceleration of the front axle; The wheel center turning moment is calculated based on the wheel center lateral force, the wheel rolling radius, and the distance between the wheel lateral force point and the wheel center; The wheel center aligning torque is calculated based on the axial force of the steering tie rod of the vehicle and the action distance between the steering tie rod ball pin action point and the kingpin.

[0085] Furthermore, in one embodiment, the device is also used for: Obtaining the strength bearing capacity loads of each chassis component in each direction during the bench strength test, wherein the strength bearing capacity loads include the yield point load and the equivalent plastic strain PEEQ2% point load, as well as the large deformation point load or the fracture point load; For each load value after the yield point load and before the large deformation point load or the fracture point load in each direction of each chassis component, a corresponding mapping relationship is constructed in combination with the corresponding equivalent plastic strain; The strength bearing capacity loads of each chassis component in each direction are converted into corresponding converted wheel center loads, and the yield point converted wheel center loads and PEEQ2% point converted wheel center loads in each direction of each chassis component, as well as the large deformation point converted wheel center loads or the fracture point converted wheel center loads are obtained.

[0086] Furthermore, in one embodiment, the first determining module is further configured to: For any chassis component, when the six components of the wheel center force are all less than or equal to the wheel center load converted from the yield point in each direction of the chassis component, it is determined that the deformation state of the chassis component is that no equivalent plastic strain occurs; When the six wheel center forces are greater than the wheel center load converted from the yield point in any direction of the chassis component, and are less than or equal to the wheel center load converted from the PEEQ2% point in each direction, it is determined that the chassis component has a first-order equivalent plastic strain, and the mapping relationship is searched according to the real-time load of the chassis component to obtain the maximum equivalent plastic strain of the chassis component; When the six wheel center forces are greater than the wheel center load converted from the PEEQ2% point in any direction of the chassis component, and are all less than the wheel center load converted from the large deformation point in each direction or the wheel center load converted from the fracture point, it is determined that the chassis component has a secondary equivalent plastic strain, and the mapping relationship is searched according to the real-time load of the chassis component to obtain the maximum equivalent plastic strain of the chassis component; When the six wheel center forces are greater than or equal to the maximum deformation point-converted wheel center load or the fracture point-converted wheel center load in any direction of the chassis component, it is determined that the chassis component has undergone a large deformation or has fractured.

[0087] Furthermore, in one embodiment, the device is also used for: When the vehicle is subjected to a proving ground durability test, pseudo damage of Q times the proving ground durability load in each direction of each chassis component is used as the pseudo damage base of the corresponding chassis component in each direction.

[0088] Furthermore, in one embodiment, the second determining module is further configured to: For any chassis component, when the chassis component does not have equivalent plastic strain, the accumulated pseudo damage of the chassis component in each direction is calculated in real time by the rain flow counting algorithm according to the six-component force of the wheel center, and the accumulated pseudo damage of the chassis component in each direction is divided by the pseudo damage base in the corresponding direction to obtain the service life in each direction, and the remaining service life of the chassis component is determined according to the maximum service life; When the deformation state of the chassis component is the first-level equivalent plastic strain or the second-level equivalent plastic strain, the impact load damage of the chassis component is calculated according to the material type and the maximum equivalent plastic strain of the component, and the damage life and the remaining life of the chassis component are obtained according to the impact load damage and the pseudo damage cardinality in the corresponding direction; When the deformation state of the chassis component is large deformation or fracture, it is determined that the remaining life of the chassis component is zero.

[0089] Furthermore, in one embodiment, the notification module is also used to: When all chassis components of the suspension system do not have plastic strain, if the wheel center longitudinal force is greater than the driver's longitudinal impact perception threshold, the wheel center lateral force is greater than the driver's lateral impact perception threshold, or the wheel center normal force is greater than the driver's normal impact perception threshold, a first status notification indicating that the chassis components are not damaged is issued, otherwise, no status notification is issued; When a chassis component has a first-level equivalent plastic strain, a second status notification for indicating that the chassis component has a first-level equivalent plastic strain is issued, and the chassis component having the first-level equivalent plastic strain and its remaining life are simultaneously displayed; When a chassis component has secondary equivalent plastic strain, a third state notification is issued to indicate that the chassis component has secondary equivalent plastic strain and that the vehicle needs to be driven with caution, and the chassis component having secondary equivalent plastic strain and its remaining life are simultaneously displayed; When there is a chassis component that is greatly deformed or broken, a fourth status notification is issued to indicate that the chassis component is greatly deformed or broken and safe driving is impossible, and the greatly deformed or broken chassis component is displayed synchronously, and the chassis component status is sent to the after-sales service end.

[0090] Furthermore, in one embodiment: The driver's longitudinal impact perception threshold is M times the maximum wheel load that the vehicle can bear; The driver's lateral impact perception threshold is N times the maximum wheel load that the vehicle can bear; The driver's normal impact perception threshold is R times the maximum wheel load that the vehicle can bear.

[0091] Among them, the functional implementation of each module in the above-mentioned device for online evaluation of vehicle parts life corresponds to the various steps in the above-mentioned method embodiment for online evaluation of vehicle parts life, and its functions and implementation processes will not be repeated here one by one.

[0092] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are only for description and do not represent the advantages or disadvantages of the embodiments.

[0093] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit "first", "second" and "third" to different types.

[0094] In the description of the embodiments of the present application, "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a specific way.

[0095] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; the “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0096] In some processes described in the embodiments of the present application, multiple operations or steps that appear in a specific order are included, but it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of the present application or in parallel, and the sequence number of the operation is only used to distinguish the different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0097] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, disk, CD) as described above, and includes a number of instructions for a terminal device to execute the methods described in each embodiment of the present application.

[0098] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for online evaluation of vehicle component life, characterized in that: The method for online evaluation of vehicle component life includes: Acquiring the six-component force of the wheel center of the vehicle during the operation of the vehicle, and determining the real-time load of each chassis component in the suspension system of the vehicle according to the six-component force of the wheel center; Determine the deformation state of each chassis component according to the six components of the wheel center, the real-time load of each chassis component and the strength bearing capacity load of each chassis component; Based on the deformation state of each chassis component, the remaining life of each chassis component is determined according to the real-time load of each chassis component and the pseudo-damage base of each chassis component; According to the deformation state and remaining life of each chassis component, combined with the six-component wheel center force and the preset driver impact perception threshold, a corresponding chassis component status notification is issued.

2. The method for online evaluation of vehicle component life according to claim 1, characterized in that: Acquiring the six-component force of the wheel center of the vehicle during the operation of the vehicle includes: The six-component force of the wheel center of the vehicle is calculated according to the unsprung acceleration, the sprung acceleration and the sprung and unsprung relative compression displacement of the vehicle collected during the operation of the vehicle.

3. The method for online evaluation of vehicle component life according to claim 2, characterized in that: The calculating of the six components of the wheel center force of the vehicle according to the unsprung acceleration, the sprung acceleration and the sprung and unsprung relative compression displacement of the vehicle collected during the operation of the vehicle comprises: The wheel center normal force of the vehicle is calculated according to the vertical stiffness of the suspension system, the relative compression displacement between the sprung and unsprung parts, the vertical damping coefficient of the suspension system, the relative compression velocity between the sprung and unsprung parts, the unsprung mass of the vehicle, and the unsprung vertical acceleration; The wheel center braking torque is calculated according to the brake hydraulic line pressure of the vehicle, the area of ​​the brake wheel cylinder piston, and the radius from the brake wheel cylinder piston to the wheel axle; When the unsprung vertical acceleration is greater than or equal to a preset first acceleration threshold, or the sprung vertical acceleration is greater than or equal to a preset second acceleration threshold, the wheel center longitudinal force of the vehicle is calculated based on the unsprung mass, the unsprung longitudinal acceleration, the longitudinal stiffness of the suspension system, and the longitudinal displacement of the unsprung mass relative to the sprung mass; When the unsprung vertical acceleration is less than a preset first acceleration threshold and the sprung vertical acceleration is less than a preset second acceleration threshold, if the vehicle is in an accelerating state, the longitudinal moment of the entire vehicle is determined according to the sprung longitudinal acceleration, and the wheel center longitudinal force of the vehicle is obtained according to the longitudinal moment of the entire vehicle; if the vehicle is in a braking state, the wheel center longitudinal force of the vehicle is calculated according to the wheel center braking moment and the wheel rolling radius of the vehicle; Calculating the wheel center lateral force of the vehicle according to the overall mass of the front axle of the vehicle and the lateral acceleration of the front axle; The wheel center turning moment is calculated based on the wheel center lateral force, the wheel rolling radius, and the distance between the wheel lateral force point and the wheel center; The wheel center aligning torque is calculated based on the axial force of the steering tie rod of the vehicle and the action distance between the steering tie rod ball pin action point and the kingpin.

4. The method for online evaluation of vehicle component life according to claim 1, characterized in that: Before determining the deformation state of each chassis component according to the six wheel center forces, the real-time load of each chassis component and the strength bearing capacity load of each chassis component, the method further includes: Obtaining the strength bearing capacity loads of each chassis component in each direction during the bench strength test, wherein the strength bearing capacity loads include the yield point load and the equivalent plastic strain PEEQ2% point load, as well as the large deformation point load or the fracture point load; For each load value after the yield point load and before the large deformation point load or the fracture point load in each direction of each chassis component, a corresponding mapping relationship is constructed in combination with the corresponding equivalent plastic strain; The strength bearing capacity loads of each chassis component in each direction are converted into corresponding converted wheel center loads, and the yield point converted wheel center loads and PEEQ2% point converted wheel center loads in each direction of each chassis component, as well as the large deformation point converted wheel center loads or the fracture point converted wheel center loads are obtained.

5. The method for online evaluation of vehicle component life according to claim 4, characterized in that: Determining the deformation state of each chassis component according to the six components of the wheel center, the real-time load of each chassis component and the strength bearing capacity load of each chassis component includes: For any chassis component, when the six components of the wheel center force are all less than or equal to the wheel center load converted from the yield point in each direction of the chassis component, it is determined that the deformation state of the chassis component is that no equivalent plastic strain occurs; When the six wheel center forces are greater than the wheel center load converted from the yield point in any direction of the chassis component, and are less than or equal to the wheel center load converted from the PEEQ2% point in each direction, it is determined that the chassis component has a first-order equivalent plastic strain, and the mapping relationship is searched according to the real-time load of the chassis component to obtain the maximum equivalent plastic strain of the chassis component; When the six wheel center forces are greater than the wheel center load converted from the PEEQ2% point in any direction of the chassis component, and are all less than the wheel center load converted from the large deformation point in each direction or the wheel center load converted from the fracture point, it is determined that the chassis component has a secondary equivalent plastic strain, and the mapping relationship is searched according to the real-time load of the chassis component to obtain the maximum equivalent plastic strain of the chassis component; When the six wheel center forces are greater than or equal to the maximum deformation point-converted wheel center load or the fracture point-converted wheel center load in any direction of the chassis component, it is determined that the chassis component has undergone a large deformation or has fractured.

6. The method for online evaluation of vehicle component life according to claim 5, characterized in that: Before determining the remaining life of each chassis component based on the deformation state of each chassis component, according to the real-time load of each chassis component and the pseudo damage base of each chassis component, it also includes: When the vehicle is subjected to a proving ground durability test, pseudo damage of Q times the proving ground durability load in each direction of each chassis component is used as the pseudo damage base of the corresponding chassis component in each direction.

7. The method for online evaluation of vehicle component life according to claim 6, characterized in that: The method of determining the remaining life of each chassis component based on the deformation state of each chassis component, according to the real-time load of each chassis component and the pseudo damage base of each chassis component, includes: For any chassis component, when the chassis component does not have equivalent plastic strain, the accumulated pseudo damage of the chassis component in each direction is calculated in real time by the rain flow counting algorithm according to the six-component force of the wheel center, and the accumulated pseudo damage of the chassis component in each direction is divided by the pseudo damage base in the corresponding direction to obtain the service life in each direction, and the remaining service life of the chassis component is determined according to the maximum service life; When the deformation state of the chassis component is the first-level equivalent plastic strain or the second-level equivalent plastic strain, the impact load damage of the chassis component is calculated according to the material type and the maximum equivalent plastic strain of the component, and the damage life and the remaining life of the chassis component are obtained according to the impact load damage and the pseudo damage cardinality in the corresponding direction; When the deformation state of the chassis component is large deformation or fracture, it is determined that the remaining life of the chassis component is zero.

8. The method for online evaluation of vehicle component life according to claim 7, characterized in that: The method of issuing a corresponding chassis component status notification based on the deformation state and remaining life of each chassis component, in combination with the six-component wheel center force and a preset driver impact perception threshold, includes: When all chassis components of the suspension system do not have plastic strain, if the wheel center longitudinal force is greater than the driver's longitudinal impact perception threshold, the wheel center lateral force is greater than the driver's lateral impact perception threshold, or the wheel center normal force is greater than the driver's normal impact perception threshold, a first status notification indicating that the chassis components are not damaged is issued, otherwise, no status notification is issued; When a chassis component has a first-level equivalent plastic strain, a second status notification for indicating that the chassis component has a first-level equivalent plastic strain is issued, and the chassis component having the first-level equivalent plastic strain and its remaining life are simultaneously displayed; When a chassis component has secondary equivalent plastic strain, a third state notification is issued to indicate that the chassis component has secondary equivalent plastic strain and that the vehicle needs to be driven with caution, and the chassis component having secondary equivalent plastic strain and its remaining life are simultaneously displayed; When there is a chassis component that is greatly deformed or broken, a fourth status notification is issued to indicate that the chassis component is greatly deformed or broken and safe driving is impossible, and the greatly deformed or broken chassis component is displayed synchronously, and the chassis component status is sent to the after-sales service end.

9. The method for online evaluation of vehicle component life according to claim 8, characterized in that: The driver's longitudinal impact perception threshold is M times the maximum wheel load that the vehicle can bear; The driver's lateral impact perception threshold is N times the maximum wheel load that the vehicle can bear; The driver's normal impact perception threshold is R times the maximum wheel load that the vehicle can bear.

10. A device for online evaluation of vehicle component life, characterized in that: The device for online evaluation of vehicle component life includes: An acquisition module, which is used to acquire the six-component wheel center force of the vehicle during the operation of the vehicle, and determine the real-time load of each chassis component in the suspension system of the vehicle according to the six-component wheel center force; A first determination module, which is used to determine the deformation state of each chassis component according to the six components of the wheel center, the real-time load of each chassis component and the strength bearing capacity load of each chassis component; A second determination module is used to determine the remaining life of each chassis component based on the deformation state of each chassis component, according to the real-time load of each chassis component and the pseudo damage base of each chassis component; The notification module is used to issue corresponding chassis component status notifications according to the deformation status and remaining life of each chassis component, combined with the six-component force of the wheel center and a preset driver impact perception threshold.

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