Hub bearing system load carrying optimization design method and system

Abstract

This invention relates to the fields of bearing design and mechanical transmission technology, specifically to a method and system for optimizing the load-bearing capacity of wheel hub bearing systems. It includes steps such as parameter acquisition, model construction, distortion correction, residual comparison, and iterative optimization. The system acquires geometric and multi-condition load parameters to construct a Hertzian contact reference model to determine the baseline stress field. Its core is the introduction of the ring structure compliance matrix and contact skew angle model to correct distortion and extract the theoretical residual distribution, then compares it with the actual residual distribution to determine the shape-correction compensation evaluation index. When the index does not meet the threshold, the system iteratively adjusts the micro-shape-correction parameters. This invention effectively eliminates macroscopic structural interference, solves the problem of difficulty in distinguishing the influence of multiple factors on the contact stress distribution, and provides a clear physical benchmark for shape correction.

Description

Technical Field

[0001] This invention relates to the field of bearing design and mechanical transmission technology, specifically to a method and system for optimizing the load-bearing capacity of a wheel hub bearing system. Background Technology

[0002] As a key load-bearing and support component in the automotive running gear, the contact state between the internal rolling elements and the raceway of the wheel hub bearing system directly affects the load uniformity, fatigue life and operational reliability under multi-axis combined working conditions such as radial load, axial load and overturning moment. Therefore, optimizing the design of contact stress distribution is an important prerequisite for ensuring the performance of wheel hub bearings.

[0003] Existing wheel hub bearing design methods have many problems. For example, they rely heavily on experience-based modification, single-condition verification, or direct adjustments based on overall simulation results. It is difficult to distinguish the individual effects of structural flexibility, contact misalignment, and micro-modification on contact stress distribution. Especially when flanged wheel hub bearing units are subjected to combined loads, it is easy to encounter situations such as excessively high peak stress at the edge of the contact area, uneven local load bearing, and inaccurate modification compensation direction. It is impossible to effectively achieve directional optimization for distorted contact conditions. Summary of the Invention

[0004] The purpose of this invention is to provide a method and system for optimizing the load-bearing capacity of a wheel hub bearing system, addressing the following technical problems: Existing wheel hub bearing design methods struggle to effectively distinguish the individual effects of structural flexibility, contact misalignment, and micro-shaping on contact stress distribution, and cannot resolve issues such as peak stress exceeding a preset threshold at the contact area edge and misalignment of the shaping compensation direction under multi-axis combined loads. Therefore, there is an urgent need for a method and system for optimizing the load-bearing capacity of a wheel hub bearing system that can separate and extract forced distortion caused by structural flexibility and perform directional micro-shaping compensation, effectively improving the local load uniformity under multi-axis combined loads. This invention can achieve its objective through the following technical solutions:

[0005] The method for optimizing the load-bearing capacity of a wheel hub bearing system includes: acquiring the geometric parameter set, multi-condition spatial load parameter set, and material constitutive data of the wheel hub bearing; the geometric parameter set includes at least the raceway curvature parameters, rolling element modification parameters, and initial clearance parameters; acquiring the ring structure compliance matrix and the rolling element contact skew angle model, the ring structure compliance matrix representing the macroscopic elastic displacement mapping relationship of the wheel hub bearing under load; under the assumptions of rigid body and isothermal temperature, constructing a Hertzian contact reference model based on the geometric parameter set and multi-condition spatial load parameter set, and determining the reference load distribution and reference contact stress field; performing distortion correction on the Hertzian contact reference model based on the ring structure compliance matrix and the rolling element contact skew angle model, determining the forced distortion stress field, and determining the theoretical residual distribution based on the difference between the forced distortion stress field and the reference contact stress field; and determining the rolling element modification parameters and / or raceway curvature parameters in the current iterative design scheme. The actual contact stress field is determined, and the actual residual distribution is determined based on the difference between the actual contact stress field and the reference contact stress field. Based on the overlap of the reverse deviation regions in the theoretical and actual residual distributions, a shape-correction compensation evaluation index is determined. The preset threshold conditions include at least: the area overlap rate of the opposite-sign regions is greater than a preset ratio, and the peak contact stress reduction rate on the stressed side reaches a set value. In response to the shape-correction compensation evaluation index meeting the preset threshold conditions, the target load-bearing optimized design scheme is output. In response to the shape-correction compensation evaluation index not meeting the preset threshold conditions, the rolling element shape-correction parameters and / or groove curvature parameters are iteratively adjusted based on the shape-correction compensation evaluation index, and the actual contact stress field determination step and the shape-correction compensation evaluation index determination step are repeated until the preset threshold conditions are met or the preset maximum number of iterations is reached. At this point, the current optimal candidate design scheme is output as the target load-bearing optimized design scheme.

[0006] Optionally, the load vector in the multi-condition spatial load parameter set is defined in a preset coordinate system and includes at least radial load parameters, axial load parameters, and overturning moment parameters; the material constitutive data includes elastic parameters and contact constitutive parameters.

[0007] Optionally, a Hertzian contact reference model is constructed based on the geometric parameter set and the multi-condition spatial load parameter set to determine the reference load distribution and the reference contact stress field, including: constructing the Hertzian contact reference model under the assumptions of rigid body, isothermal and preset no manufacturing error; distributing the load on the Hertzian contact reference model according to the multi-condition spatial load parameter set to determine the reference load distribution; and determining the reference contact stress field based on the reference load distribution.

[0008] Optionally, the Hertzian contact reference model is distorted based on the ring structure compliance matrix and the rolling element contact skew angle model to determine the forced distortion stress field. The theoretical residual distribution is then determined based on the difference between the forced distortion stress field and the reference contact stress field. This includes: calculating the radial displacement, axial displacement, and tilt deformation under load based on the inner and / or outer ring structure compliance matrices; calculating the skew angle of the rolling element relative to the raceway contact normal based on the rolling element contact skew angle model to obtain the contact skew amount; determining the forced distortion stress field based on the radial displacement, axial displacement, tilt deformation, and contact skew amount; and determining the theoretical residual distribution based on the positional stress difference between the forced distortion stress field and the reference contact stress field within the contact area.

[0009] Optionally, the reshaping compensation evaluation index is determined based on the overlap relationship between the reverse deviation regions in the theoretical residual distribution and the actual residual distribution. This includes: comparing the theoretical residual distribution and the actual residual distribution to determine the area overlap rate of the regions with opposite signs; determining the degree of residual reverse compensation based on the area overlap rate; and determining the reshaping compensation evaluation index based on the degree of residual reverse compensation.

[0010] The wheel hub bearing system load optimization design system includes a processor and a memory. The memory stores program instructions. The system includes: a data acquisition module for acquiring the geometric parameter set, multi-condition spatial load parameter set, and material constitutive data of the wheel hub bearing; a reference model construction module for constructing a Hertzian contact reference model and determining the reference load distribution and reference contact stress field; a distortion correction module for correcting the distortion of the Hertzian contact reference model based on the ring structure compliance matrix and rolling element contact skew angle model, and determining the forced distortion stress field and theoretical residual distribution; and the actual residual... The determination module is used to determine the actual contact stress field and the actual residual distribution based on the rolling element shaping parameters and / or groove curvature parameters in the current iterative design scheme. The evaluation and decision module is used to determine the shaping compensation evaluation index based on the theoretical residual distribution and the actual residual distribution. The closed-loop optimization module is used to output the target load-bearing optimization design scheme when the shaping compensation evaluation index meets the preset threshold condition, and to adjust the rolling element shaping parameters and / or groove curvature parameters and trigger the actual residual determination module and the evaluation and decision module to continue execution when the shaping compensation evaluation index does not meet the preset threshold condition.

[0011] Optionally, the data acquisition module includes: a geometric parameter acquisition unit for acquiring groove curvature parameters, rolling element shaping parameters, and initial clearance parameters; a load data acquisition unit for acquiring radial load parameters, axial load parameters, and overturning moment parameters; and a material data acquisition unit for acquiring material constitutive data, which includes elastic parameters and contact constitutive parameters.

[0012] Optionally, the evaluation and decision module includes: a residual comparison unit for comparing the theoretical residual distribution with the actual residual distribution; an overlap rate determination unit for determining the area overlap rate of regions with opposite signs based on the comparison processing results; a compensation degree determination unit for determining the degree of residual reverse compensation based on the area overlap rate; and a decision unit for determining the shape correction compensation evaluation index based on the degree of residual reverse compensation.

[0013] Optionally, the closed-loop optimization module includes: a condition judgment unit, used to judge whether the shape compensation evaluation index meets the preset threshold condition; a parameter adjustment unit, used to iteratively adjust the rolling element shape parameters and the groove curvature parameters according to the shape compensation evaluation index when the shape compensation evaluation index does not meet the preset threshold condition; and a result output unit, used to output the target load-bearing optimization design scheme when the shape compensation evaluation index meets the preset threshold condition.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. This invention determines the reference contact stress field by constructing a Hertzian contact reference model under the assumptions of rigid body and isothermal temperature, and introduces the compliance matrix of the ring structure and the contact skew angle model of the rolling element for distortion correction to extract the theoretical residual distribution. This mechanism effectively removes the interference at the macroscopic structural level and solves the problem that the existing technology is unable to distinguish the respective effects of structural compliance, contact skew and micro-shape modification on the contact stress distribution, providing a clear physical benchmark and theoretical basis for subsequent shape modification.

[0016] 2. This invention compares the overlap of the reverse deviation regions in the theoretical residual distribution and the actual residual distribution, and determines the shape correction compensation evaluation index based on the area overlap rate of the opposite sign regions and the degree of residual reverse compensation. This evaluation mechanism based on spatial distribution overlap replaces the traditional single evaluation method that only uses the single point stress peak as the judgment basis, effectively solving the problem of inaccurate shape correction compensation direction that is easy to occur in the prior art, and ensuring that micro-shape correction can offset stress deterioration in the correct region and in the correct direction.

[0017] 3. This invention obtains a unified set of spatial load parameters and material constitutive data for multiple working conditions defined in a preset coordinate system. This standardized data acquisition method provides a unified physical reference for benchmark modeling and distortion analysis, overcomes the problem of uneven local load caused by the reliance on single working condition verification in traditional methods, and effectively improves the accuracy of load analysis under multi-axis combined working conditions.

[0018] 4. This invention determines whether the shape compensation evaluation index meets the preset threshold condition, and if not, iteratively adjusts the rolling element shape parameters and / or groove curvature parameters according to the index, thereby repeatedly executing the actual contact stress field determination and evaluation judgment steps; this mechanism breaks the defect of unconstrained shape adjustment based directly on the overall simulation results or experience in traditional design, and achieves stable convergence of suppressing excessively high peak stress at the edge of the contact area and outputting the target load-bearing optimized design scheme;

[0019] 5. This invention integrates a data acquisition module, a benchmark model construction module, a distortion correction module, an actual residual determination module, an evaluation and decision module, and a closed-loop optimization module to form a complete system. This architecture transforms abstract optimization design methods into an engineering process that can be implemented, ensuring the accuracy and consistency of the flow of design schemes, geometric parameter sets, and residual distribution data at each stage, and making the load-bearing optimization process under complex working conditions highly standardized and traceable. Attached Figure Description

[0020] The present invention will be further explained below with reference to the accompanying drawings and embodiments:

[0021] Figure 1 This is a flowchart of the method of the present invention;

[0022] Figure 2 This is a structural diagram of the system of the present invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0024] Example 1:

[0025] Please see Figure 1The method for optimizing the load-bearing capacity of a wheel hub bearing system includes: acquiring the geometric parameter set, multi-condition spatial load parameter set, and material constitutive data of the wheel hub bearing; the geometric parameter set includes at least the raceway curvature parameter, rolling element modification parameter, and initial clearance parameter; acquiring the ring structure compliance matrix and the rolling element contact skew angle model, the ring structure compliance matrix characterizing the macroscopic elastic displacement mapping relationship of the wheel hub bearing under load; under the assumptions of rigid body and isothermal temperature, constructing a Hertzian contact reference model based on the geometric parameter set and multi-condition spatial load parameter set, and determining the reference load distribution and reference contact stress field; performing distortion correction on the Hertzian contact reference model based on the ring structure compliance matrix and the rolling element contact skew angle model, determining the forced distortion stress field, and determining the theoretical residual distribution based on the difference between the forced distortion stress field and the reference contact stress field; and determining the theoretical residual distribution based on the rolling element modification parameter and / or raceway curvature parameter in the current iterative design scheme. The actual contact stress field is determined, and the actual residual distribution is determined based on the difference between the actual contact stress field and the reference contact stress field. Based on the overlap of the reverse deviation regions in the theoretical and actual residual distributions, a shape-correction compensation evaluation index is determined. The preset threshold conditions include at least: the area overlap rate of the opposite-sign regions is greater than a preset ratio, and the peak contact stress reduction rate on the stressed side reaches a set value. In response to the shape-correction compensation evaluation index meeting the preset threshold conditions, the target load-bearing optimized design scheme is output. In response to the shape-correction compensation evaluation index not meeting the preset threshold conditions, the rolling element shape-correction parameters and / or groove curvature parameters are iteratively adjusted based on the shape-correction compensation evaluation index, and the actual contact stress field determination step and the shape-correction compensation evaluation index determination step are repeated until the preset threshold conditions are met, or the preset maximum number of iterations is reached. At this point, the current optimal candidate design scheme is output as the target load-bearing optimized design scheme.

[0026] This embodiment provides a mechanism for optimizing the load-bearing design of a wheel hub bearing system. Specifically, taking the final development scenario of a flanged wheel hub bearing unit as an example, before the prototype is frozen, it is necessary to improve the local load uniformity under multi-axis combined loads without enlarging the bearing's outer dimensions. This is to avoid early indentation, spalling, or microplastic damage caused by the edge stress peak in the contact area between the rolling elements and the raceway exceeding the preset safety threshold. In this continuous development scenario, this embodiment does not use the final finite element results as the sole basis. Instead, it establishes an ideal contact benchmark, separates and extracts the distortion caused by structural flexibility, and compensates for the distortion based on micro-shaping, thereby forming a closed-loop optimization.

[0027] The process involves acquiring geometric parameter sets, multi-condition spatial load parameter sets, and material constitutive data. The geometric parameter set reflects the original internal geometry and adjustable design degrees of freedom of the bearing. For example, the groove curvature determines the unfolding trend of the contact ellipse, the rolling element shaping parameters determine the transition smoothness of the contact area edge, and the initial clearance determines the order and extent to which each rolling element enters the load-bearing area after loading. The multi-condition spatial load parameter set describes the multi-directional combined forces and moments transmitted from the flange end face to the bearing interior, essentially corresponding to the load input spectrum of the bearing rings under different stress postures. The material constitutive data defines the contact elastic deformation capacity and local contact response characteristics, avoiding the misattribution of phenomena that should be explained by material contact behavior to geometric mismatch.

[0028] A Hertzian contact reference model is constructed under the rigid body assumption and the isothermal assumption. The rigid body assumption here does not mean that the actual raceway does not deform in an ideal state, but rather to establish an ideal mechanical reference state that excludes structural flexibility interference, so that the contact between the rolling element and the raceway retains only the stress distribution characteristics corresponding to the ideal Hertzian contact. The isothermal assumption is used to shield the additional effects of temperature factors such as thermal expansion and lubrication temperature rise on clearance and contact patch morphology, so that the reference model focuses on the basic mechanical relationship between geometry and external load. From this, the reference load distribution and the reference contact stress field can be obtained. This reference field can be understood as a reference spectrum of how the contact stress should be distributed if the raceway does not undergo macroscopic elastic distortion.

[0029] After obtaining the baseline diagram, the compliance matrix of the bearing structure and the rolling element contact skew angle model are introduced to correct the distortion of the reference model, resulting in a forced distortion stress field. Its physical significance lies in the fact that the inner ring, outer ring, and flange-related parts in a real bearing are not absolutely rigid. When multi-axis loads are input, the bearing will exhibit radial deflection, axial movement, and local tilting. The relationship between the rolling element and the raceway normal will change accordingly, causing the originally centered contact patch to shift to one side, and resulting in a lifting stress concentration at the contact edge. Subtracting this forced distortion stress field from the aforementioned baseline contact stress field yields the theoretical residual distribution. This theoretical residual does not represent the final design result but rather the deterioration trend caused solely by structural compliance and attitude skew.

[0030] In the same design iteration, the actual contact stress field is determined based on the current rolling element shaping parameters and / or groove curvature parameters, and the difference between it and the reference contact stress field is used to obtain the actual residual distribution. The actual residual here includes the compensation effect generated by the current shaping design. For example, logarithmic shaping can weaken the peak load at the contact boundary of the rolling element end, and groove curvature adjustment can change the direction and area of ​​the principal axis of the contact ellipse, thereby redistributing the local load ratio.

[0031] An overlap analysis of the reverse deviation region is performed on the theoretical residual distribution and the actual residual distribution. The so-called reverse deviation region refers to a region where the theoretical residual shows that the stress is higher than the ideal reference, while the actual residual in the same region shows a decrease relative to the reference, or vice versa. The more complete this overlap, the closer the current shaping is to mirror compensation for the forced distortion. For ease of explanation, a simplified regional diagram can be used: the contact area is divided into three sub-regions: left edge, middle, and right edge. If the theoretical residual shows high on the left, stable in the middle, and high on the right, while the actual residual of the current design shows a decrease on the left, stable in the middle, and a decrease on the right, it indicates that the compensation direction is correct. If the actual residual shows higher on the left, stable in the middle, and higher on the right, it indicates that the shaping and distortion directions overlap, which is an unfavorable design. The system generates shaping compensation evaluation indicators based on this.

[0032] If the shape compensation evaluation index meets the preset threshold conditions, the target load optimization design scheme is output. The preset threshold conditions are generated based on the historical bench fatigue test data of similar flanged wheel hub bearings and the local safety factor requirements of the target model. Specifically, the area overlap rate is required to be greater than the preset empirical ratio, and the rate of decrease of the peak contact stress on the stressed side reaches the set expected improvement in fatigue life. If not met, the rolling element shape parameters and / or groove curvature parameters are adjusted according to the index, and the actual contact stress field determination and evaluation steps are repeated. The iterative adjustment here usually takes priority on the rolling element shape parameters, and can also be linked with the groove curvature parameters and clearance settings, so that the contact area gradually returns from local overload to a state of stable load-bearing in the middle and smooth transition at the edges.

[0033] In one possible implementation, when there is a significant conflict between input load conditions, such as one condition requiring a central load of a certain proportion or higher, while another condition requires stronger edge unloading, the system can perform hierarchical optimization according to pre-set load condition weights. The pre-set load condition weights are determined based on the frequency distribution ratio of each multi-axle combined load condition and the corresponding fatigue damage contribution ratio in bearing real vehicle road surface spectrum testing or vehicle multi-body dynamics simulation. First, ensure that no dangerous edge peak occurs under the ultimate load condition, and then take into account the fatigue uniformity of commonly used conditions. If material constitutive data is missing, the source of bearing compliance data is unreliable, or the narrowing of the contact area in a certain iteration exceeds the preset area lower limit, then continue the iteration, retain the previous stable design as a fallback plan, so as to avoid amplifying the erroneous input into the erroneous output.

[0034] For example, during the finalization process of the aforementioned flange-type wheel hub bearing unit, it was found that under the superposition of radial load, axial load, and overturning moment, a high stress zone appeared on the contact edge of a set of rolling elements near the force-bearing side. The system established an ideal Hertzian contact reference to obtain a balanced elliptical contact spot. After injecting ring compliance and contact skew, the theoretical residual showed that there was a significant lifting area on the edge of the force-bearing side. The first round of micro-modification scheme only reduced the end of the rolling element by the first preset step size, and the reverse overlap between the actual residual and the theoretical residual was insufficient, indicating that the compensation was insufficient. After the second round of increasing the logarithmic modification range of the rolling element and adjusting the groove curvature, the reverse overlap area expanded to be greater than the preset area threshold, and the contact edge peak fell back. Based on this, the system outputs this set of parameters as the target scheme.

[0035] The purpose of this step is to separate and identify the system-level deterioration caused by structural flexibility from the local compensation caused by micro-modification, so as to achieve targeted modification optimization for the internal contact state of the wheel hub bearing, rather than relying on experience to enlarge the size or generally increase the safety factor.

[0036] Furthermore, to avoid ambiguity in understanding the rigid body assumption and the Hertzian contact mechanism, the rigid body assumption in this embodiment is only used to exclude the overall compliance effect of macroscopic structural components such as raceways and flanges, and does not exclude the Hertzian elastic indentation that occurs between the rolling elements and the raceway in the local contact patch based on material constitutive data; in other words, what is artificially frozen in the benchmark model is the system-level deflection, sway, and tilting degrees of freedom, while what is retained is the elastic response necessary for local contact. Therefore, the aforementioned benchmark contact stress field is still calculable and physically meaningful.

[0037] Furthermore, based on the rolling element profile and / or channel curvature parameters in the current iterative design scheme, the actual contact stress field is determined. The same load boundary, coordinate definition, and contact area discretization method as the reference model can be used. Only the candidate rolling element profile and / or local channel curvature are replaced in the corresponding contact pair, and the contact patch pressure distribution is recalculated under the same material parameters and the same working conditions. In this way, the actual contact stress field obtained has a one-to-one correspondence with the reference contact stress field, avoiding the misinterpretation of mesh differences, boundary differences, or differences in working condition definitions as the profile modification effect.

[0038] Furthermore, during the iterative adjustment process, the system can optimize in the order of direction, amplitude, and linkage: first, determine whether the danger zone is located at the end or near the middle of the rolling element to determine whether to prioritize adjusting the end profile or the groove curvature; then, increase or decrease the profile amplitude according to whether the reverse overlap is insufficient or whether overcompensation has occurred; when adjusting a single parameter alone cannot continue to improve the situation, another parameter is linked to correct it together; through this sequential processing, the parameter changes in each iteration can have a clear engineering direction, rather than unconstraining all design degrees of freedom at the same time.

[0039] Furthermore, to ensure the unique physical meaning of the material constitutive data throughout the text, the material constitutive data in this embodiment always refers to the same set of input data used for local contact calculations, including at least elastic parameters and contact constitutive parameters; the solutions for the reference contact stress field, the forced distortion stress field, and the actual contact stress field all call this same set of material constitutive data, and the differences only come from geometric parameters, load input, structural compliance correction, and candidate rolling element shaping parameters and / or channel curvature parameters; this avoids mixing different material batches, different temporary material cards, or different contact solution settings into the same round of residual comparison;

[0040] Furthermore, to avoid ambiguity between rolling element modification parameters, groove curvature parameters, and rolling element modification parameters and / or groove curvature parameters, in this embodiment, rolling element modification parameters and / or groove curvature parameters are used as a general term for the current iterative design scheme, referring to the set of candidate parameters that directly participate in the local compensation of the contact area; in the preferred case, it at least includes rolling element modification parameters, and when linkage optimization is required, it may also include the local adjustment amount of groove curvature parameters; accordingly, when rolling element modification parameters or groove curvature parameters are mentioned separately in the text, they refer to the specific sub-items in this general term, rather than a separate independent parameter system;

[0041] Furthermore, to facilitate the traceability of calculation results in each round, the system can fix a set of reference contact area coordinate indices in each iteration, and store the reference contact stress field, theoretical residual distribution, and actual residual distribution using fields with the same name; among them, the theoretical residual distribution only represents the difference distribution between the forced distortion stress field and the reference contact stress field, and the actual residual distribution only represents the difference distribution between the actual contact stress field under the current candidate shaping scheme and the same reference contact stress field. The names and meanings of the two are consistent throughout the text and are not confused with any experimental residuals, manufacturing error residuals, or temperature residuals;

[0042] The load vectors in the multi-condition spatial load parameter set are defined in a preset coordinate system and include at least radial load parameters, axial load parameters, and overturning moment parameters; the material constitutive data include elastic parameters and contact constitutive parameters.

[0043] This embodiment provides a mechanism for standardizing load and material inputs. Specifically, in the aforementioned prototype development scenario, if only a single load parameter is input, it is usually difficult to support the stable optimization of the model, because the contact state inside the wheel hub bearing is not only related to the load magnitude, but also to the load direction, the action posture, and the material contact response. If different working conditions are mixed under different coordinate descriptions, the system is prone to misjudging the same physical state as different states, resulting in distortion of the subsequent baseline model and distortion correction.

[0044] Therefore, this embodiment defines the load vector of the multi-condition spatial load parameter set uniformly under a preset coordinate system. This coordinate system can take the bearing rotation center as the origin, define the axial direction with the axis direction, and define the radial components with two orthogonal directions perpendicular to the axis. In this way, no matter whether the input comes from the test bench, structural simulation or historical load spectrum, it can be unified into the same physical reference frame. The radial load parameter reflects the main bearing pressure source of the rolling element in the circumferential direction, the axial load parameter determines the degree of pushing in the contact angle direction, and the overturning moment parameter determines whether the raceway undergoes a posture change of one side being pressed and the other side being unloaded. Only after the three are superimposed can the division of labor between the load-bearing area and the non-load-bearing area of ​​double or multiple rows of rolling elements be truly reconstructed.

[0045] Material constitutive data includes at least elastic parameters and contact constitutive parameters. Elastic parameters describe the overall elastic response of the raceway and rolling elements under stress, affecting the contact area size and load diffusion. Contact constitutive parameters constrain the propagation of compressive stress in the local contact area, enabling the model to distinguish between two different sources of phenomena: a harder material leading to a more concentrated contact area and geometrically poor conditions causing abnormal local edge peaks. In other words, the former pertains to material response, while the latter pertains to structural and morphological mismatch, and the two should be adjusted in different directions in design decisions.

[0046] For ease of explanation, a simplified diagram of the operating conditions can be used: there are operating conditions A and B. Operating condition A is characterized by high radial force, low axial force, and low overturning, while operating condition B is characterized by medium radial force, medium axial force, and high overturning. If both are defined in the same coordinate system, the system can directly identify that operating condition B is more likely to induce stress rise on one side of the edge. If the two are defined in different coordinate systems and have not been converted, the overturning effect may be mistaken for pure axial thrust, leading to incorrect adjustment of the channel curvature.

[0047] In one possible implementation, if the external input only provides the total load without breaking it down into radial, axial, and overturning moments, the system can refuse to directly enter the optimization process and prompt for load decomposition. If the material database lacks contact constitutive parameters, standard contact parameters of the same type of steel can be used as temporary values, but the results of this round should be marked as pending review to avoid using temporary material data directly in the final frozen design.

[0048] For example, during the development of the aforementioned flange-type wheel hub bearing unit, three sets of combined loads were obtained. One set mainly exhibited high radial load, another set mainly exhibited axial load, and the third set showed obvious overturning characteristics. The system first converted all three sets of inputs to a unified coordinate system, and then called the elastic parameters and contact constitutive parameters of the same batch of ring and rolling element materials. After unified processing, the developers could clearly see that the most dangerous condition was not the one with the largest total load, but the one with the most prominent overturning moment, because it was more likely to form skewed contact on the stressed side.

[0049] The purpose of this step is to provide the same physical reference for subsequent benchmark modeling and distortion analysis, thereby achieving comparability between load conditions from different sources and avoiding misjudgments caused by inconsistent load representations or incomplete material data.

[0050] A Hertzian contact reference model is constructed based on the geometric parameter set and the multi-condition spatial load parameter set. The reference load distribution and reference contact stress field are determined, including: constructing the Hertzian contact reference model under the assumptions of rigid body, isothermal and preset no manufacturing error; distributing the load on the Hertzian contact reference model according to the multi-condition spatial load parameter set to determine the reference load distribution; and determining the reference contact stress field based on the reference load distribution.

[0051] This embodiment provides a mechanism for ideal benchmark reconstruction. Specifically, in the aforementioned process, if the simulation results of the actual prototype are directly used as a reference, manufacturing errors, assembly deviations, temperature rise changes and structural flexibility will be coupled together, making it difficult to distinguish between distortions that are not expected in the design and normal load migration within the design allowable range. Therefore, this embodiment introduces an additional condition of no manufacturing error to further purify the reference model based on the rigid body assumption and the isothermal assumption.

[0052] The so-called pre-set no manufacturing error condition means that when establishing the Hertzian contact reference model, the raceway profile, rolling element diameter, assembly coaxiality, and surface morphology are assumed to be in an ideal state, without introducing factors such as roundness error, waviness error, local pits, or eccentric assembly. The resulting contact relationship is the theoretical contact result of the design geometry itself under the premise of ideal assembly. The load is distributed to the reference model according to the multi-condition spatial load parameter set. The load distribution here is not a simple average, but rather based on the load differences of the rolling elements at their circumferential positions, mapping the external combined load to the distribution state of the load-bearing strength of each rolling element. Its physical meaning is that in a real bearing, the total load is always first manifested as several rolling elements entering the main load-bearing area, and then the proportion of each element's load is determined by the contact stiffness and contact angle relationship.

[0053] After obtaining the reference load distribution, the reference contact stress field can be determined. The reference contact stress field describes the contact patch morphology and compressive stress distribution that each main load-bearing rolling element should exhibit under ideal geometry. For example, in an ideal state, the contact patch should mainly exhibit a smooth rise in the middle and natural decay at the edges, rather than a single-sided abnormal peak. This can be illustrated using a simplified diagram: a single contact patch is roughly divided into a left edge sub-region, a central core sub-region, and a right edge sub-region along the length of the rolling element. Under the ideal reference, the stress is usually highest in the central core sub-region, and gradually decreases at both ends of the left and right edge sub-regions. If the actual results show a sudden rise in the left edge sub-region, it indicates that distortion factors outside the ideal reference have been introduced.

[0054] In one possible implementation, if a certain input geometric parameter itself exceeds the applicable range of Hertzian contact, for example, if the extreme abnormality of the channel curvature causes the local contact to no longer meet the conventional contact patch assumption, the system can terminate the construction of the benchmark model and mark the design as an invalid candidate; if the load directions between multiple working conditions are completely opposite, the system can construct the benchmark distribution corresponding to each working condition separately, and then extract the dangerous area through the envelope method, instead of forcibly mixing the contradictory load fields into a single reference spectrum;

[0055] For example, in the prototype development mentioned above, it was found that although the total load-bearing capacity of a certain group of test specimens met the standard, local indentations repeatedly appeared at the end of the rolling element on the force-bearing side. Based on this, the system first eliminated manufacturing and assembly factors and established an error-free ideal Hertz reference model. The model showed that, under the same external load, theoretically, the contact patch should maintain the central load-bearing dominance and only make a smooth transition at the edge. This indicates that the indentation does not originate from the ideal geometry itself, but is affected by the structural flexibility and attitude deviation that need to be analyzed later.

[0056] The purpose of this step is to construct an ideal contact reference that eliminates the above-mentioned interference factors, so as to achieve a unified comparison basis for subsequent theoretical residuals and actual residuals, and avoid mistaking phenomena that originally belong to error sources as design intrinsic characteristics.

[0057] Furthermore, the rigid body assumption in this embodiment does not conflict with Hertzian contact. It is defined that the collar and related support structure do not participate in macroscopic flexibility deformation, while the contact area still undergoes normal indentation based on elastic parameters and contact constitutive parameters. In other words, the reference model obtains local elastic contact under ideal attitude by shielding system-level structural distortion. Therefore, it can maintain the physical basis of Hertzian contact solution and satisfy the reference purity when subtracting from the forced distortion stress field.

[0058] Furthermore, by allocating loads to the Hertzian contact reference model based on the multi-condition spatial load parameter set, the set of rolling elements entering the load-bearing zone under each condition can be identified first. Then, based on the normal approach amount and initial clearance relationship of each rolling element at its circumferential position, it can be determined whether it participates in the load-bearing process and the relative degree of its participation. The allocation results are then mapped onto the local contact spots of each contact pair. This method of first determining the load-bearing qualification and then determining the load-bearing ratio avoids simply treating all rolling elements as equal loads, thus making the reference load distribution closer to the actual force logic inside the bearing.

[0059] Furthermore, the determination of the reference contact stress field preferably adopts a unified contact area coordinate grid to ensure that the subsequent theoretical residual distribution and the actual residual distribution can be compared point by point at the same discrete position. If the number of rolling elements actually entering the load-bearing area under a certain working condition is different from that under other working conditions, the system can first complete the point-by-point modeling in each working condition, and then map it to a unified dangerous area index for subsequent comparison, without requiring all working conditions to have the same contact patch size.

[0060] The Hertzian contact reference model is distorted based on the ring structure compliance matrix and the rolling element contact skew angle model to determine the forced distortion stress field. The theoretical residual distribution is then determined based on the difference between the forced distortion stress field and the reference contact stress field. This includes: calculating the radial displacement, axial displacement, and tilt deformation under load based on the inner and / or outer ring structure compliance matrices; calculating the skew angle of the rolling element relative to the raceway contact normal based on the rolling element contact skew angle model to obtain the contact skew amount; determining the forced distortion stress field based on the radial displacement, axial displacement, tilt deformation, and contact skew amount; and determining the theoretical residual distribution based on the positional stress difference between the forced distortion stress field and the reference contact stress field within the contact area.

[0061] This embodiment provides a mechanism for forced distortion extraction. Specifically, while simply establishing an ideal benchmark can explain how contact should occur, it still cannot explain why the actual prototype suddenly experiences edge stress concentration under certain combined operating conditions. Especially in the flanged wheel hub bearing unit, the race is not an isolated rigid body, and its connection area and cross-sectional structure will undergo elastic deflection under external load. If these structural flexibility are not explicitly introduced, subsequent shaping design is prone to blind adjustment of local parameters, and cannot effectively compensate for the distortion causes.

[0062] Based on the structural compliance matrix of the inner and / or outer rings, the radial displacement, axial displacement, and tilt deformation under load are calculated. The structural compliance matrix is ​​obtained by performing finite element static simulation analysis on the three-dimensional solid model of the ring and related support structure and extracting the nodal compliance data. The rolling element contact skew angle model is constructed based on the local mechanical equilibrium equation and is used to characterize the local geometric deflection response between the rolling element and the raceway due to the coupling of normal force and friction force under macroscopic forced displacement boundary conditions.

[0063] The compliance matrix can be understood as a structural mapping relationship in which loads in different directions cause displacement and rotational responses in different directions. Its engineering significance is that what appears to be a simple combination of loads on the outside does not only produce compression in one direction when it is transmitted to the raceway, but is often accompanied by tilting and local warping. These attitude changes will redistribute the rolling element contact load.

[0064] Based on the rolling element contact skew angle model, the skew angle of the rolling element relative to the contact normal of the raceway is determined, and the contact skew amount is obtained. The skew here does not refer to the macroscopic instability of the rolling element, but rather to the rotational angular displacement within a preset tolerance range in the contact normal direction relative to the ideal state, which changes the original symmetrical ellipse of the contact area into an oblique contact patch that is biased to one side. It is this skew that will form a higher local contact compressive stress at one end of the rolling element in the length direction.

[0065] By applying radial displacement, axial displacement, tilt deformation, and contact skew to the reference model, the forced distortion stress field can be obtained. This reflects the deteriorating trend of the internal contact state of the bearing, driven only by structural flexibility and attitude skew, without any targeted micro-modification. Furthermore, by subtracting the forced distortion stress field from the reference contact stress field at each position in the contact area, the theoretical residual distribution can be formed. For ease of understanding, a simplified three-zone diagram can be used: if the reference contact spot has a smooth distribution of 2, 5, 2 in the left edge sub-zone, the central core sub-zone, and the right edge sub-zone, and becomes 4, 5, 1 after forced distortion, then the theoretical residual shows that the left side rises, the center remains unchanged, and the right side decreases. This indicates that structural flexibility is pushing the contact spot to the left edge.

[0066] In one possible implementation, if the compliance matrix can only cover the inner circle and cannot reliably characterize the outer circle, the system can first use unilateral compliance for conservative estimation and mark the result as local compliance modeling; if the contact skew angle exceeds the preset effective range, it indicates that the current structure or load has reached the preset abnormal contact state critical value. At this time, it will no longer continue to rely solely on shape compensation, but should be fed back to the upstream structural design stage to check whether the flange thickness, collar section or support boundary conditions need to be corrected synchronously.

[0067] For example, in the prototype development described above, the flange connection area on the stressed side exhibited slight warping under high overturning conditions. The system mapped the structural response to radial displacement, axial displacement, and tilt deformation, and combined this with rolling element contact skew analysis to obtain a distorted contact diagram that clearly shifted towards the stressed side end. After comparison with the ideal baseline, the theoretical residual clearly showed that the edge of the stressed side was a high-risk lifting zone, while the other side showed contact fallback. This provided a clear compensation direction map for subsequent micro-shaping.

[0068] The purpose of this step is to explicitly separate the effect of macroscopic structural flexibility on microscopic contact deterioration, so as to achieve targeted compensation in subsequent shape modification design, rather than performing non-directional global averaging of contact stress anomalies.

[0069] Based on the overlap between the theoretical and actual residual distributions in the reverse deviation region, the shaping compensation evaluation index is determined, including: comparing the theoretical and actual residual distributions to determine the area overlap rate of the region with opposite signs; determining the degree of residual reverse compensation based on the area overlap rate; and determining the shaping compensation evaluation index based on the degree of residual reverse compensation.

[0070] This embodiment provides a mechanism for shape correction compensation judgment. Specifically, the aforementioned process has obtained the theoretical residual and the actual residual, but if only the peak value is compared, misjudgment may still occur. The reason is that the effectiveness of micro-shape correction is not only reflected in whether a certain maximum value has been reduced, but also in whether it is compensated in the correct position and in the correct direction. If only a single peak value is considered, there may be a transfer risk of one position decreasing and another position increasing. Therefore, this embodiment introduces the overlapping relationship of the reverse deviation region as the core of evaluation.

[0071] By comparing the theoretical and actual residual distributions, regions with opposite signs are identified. These opposite signs can be interpreted as opposite deviation directions: theoretical residuals show an increase in stress relative to the reference stress in a certain region, while actual residuals show a decrease in stress relative to the reference stress in that region, indicating that the current modification is counteracting this worsening trend. If the two are in the same direction, it means that the current design is not compensating but amplifying the original distortion. The degree of reverse compensation of the residuals is determined based on the area overlap rate of the regions with opposite signs. A higher area overlap rate indicates that the compensation effect covers a more complete dangerous area, rather than only being effective locally and occasionally.

[0072] A simplified discrete region diagram can be used for illustration; the contact area is discretized into four small blocks: Block 1, Block 2, Block 3, and Block 4, where Blocks 1 to 4 represent four discrete sub-regions sequentially numbered under the same contact area coordinates; if the theoretical residual is positive in Blocks 1 and 2, and zero or negative in Blocks 3 and 4; if the actual residual of a certain design round is negative in Blocks 1 and 2, it indicates that the reverse overlap is concentrated in the danger zone, and the compensation direction is correct; if the actual residual only shows a negative deviation in Block 3, while Blocks 1 and 2 are still positive, although there is a downward area overall, it does not cover the set high-stress risk area and should not be judged as the preferred solution;

[0073] The degree of residual reverse compensation forms a shaping compensation evaluation index; this index can be a comprehensive quantity, used to simultaneously reflect the coverage, directional consistency and local peak mitigation of the compensation area; in practical applications, it can be used as a stopping condition for closed-loop optimization: when the evaluation index reaches the preset level, it means that the current shaping has basically formed a corresponding offset relationship with the theoretical distortion, and the target design can be output; if the evaluation index continues to be low, it means that the micro-shaping direction, magnitude or position still needs to be adjusted.

[0074] In one possible implementation, if the theoretical residual itself is lower than the preset disturbance threshold, it indicates that the structural flexibility has a limited impact on contact deterioration under this condition. In this case, excessive shaping is not advisable to avoid introducing new contact losses. If the actual residual shows a reversal greater than the preset area ratio but is accompanied by a significant reduction in the contact area, the system should be judged as having an overcompensation risk, because although the edge is weakened, the small contact area will bring about a new increase in the central pressure. In this case, it should revert to the baseline scheme with a smaller shaping range, rather than simply pursuing a larger reverse overlap.

[0075] For example, in the above prototype development process, after the second round of design enlarged the end of the rolling element, the high-risk zone on the stress side in the theoretical residual and the fallback zone in the actual residual overlapped significantly, indicating that the modified area had effectively covered the distortion area caused by the structural flexibility. If the third round of design continues to enlarge the modification, although the edge peaks at some positions are further reduced, the central contact area is significantly narrowed. Based on this, the system identifies it as overcompensation and no longer continues to adjust in this direction. Instead, it selects the previous round of design as a more balanced result.

[0076] The purpose of this mechanism is to determine the effectiveness of the shaping by evaluating the spatial overlap between the shaping region and the theoretical distortion region, thereby achieving a spatialized judgment on the quality of micro-shaping, rather than making a one-sided judgment based solely on the magnitude of stress at a single point.

[0077] Furthermore, to improve the feasibility of the evaluation, the area overlap rate is preferably calculated under the coordinates of the unified contact area, and only the positions where the absolute value of the theoretical residual exceeds the preset risk threshold are counted. The weak fluctuation area below the threshold is not considered as the main evaluation area. The preset risk threshold is a preset percentage of the maximum contact compressive stress in the benchmark contact stress field, which is used to filter out negligible calculation cutoff errors and small numerical fluctuations.

[0078] This avoids the amplified impact of edge noise or minor numerical fluctuations on compensation determination, making the area overlap rate more accurately reflect the true coverage of the danger zone.

[0079] Furthermore, in addition to considering the area overlap rate, the degree of residual reverse compensation can also be interpreted by combining the continuity of residual fallback in the reverse region. That is, the scheme that forms continuous coverage of the main risk zone is preferred over the scheme that only forms multiple discrete small patches. This treatment does not change the evaluation chain in the embodiment, but is used to illustrate how the system distinguishes between effective compensation and accidental offsetting under the same area overlap rate.

[0080] Furthermore, if a quantitative criterion is required, the area overlap rate can be expressed as:

[0081] ;

[0082] The area overlap rate is denoted as . The area of ​​the overlapping region where the theoretical residual and the actual residual have opposite signs and are above the risk threshold is denoted as . The total area of ​​the hazardous region exceeding the risk threshold in the theoretical residual is denoted as... ;when When the residual is high and the reverse region continuously covers the main risk zone, the degree of reverse compensation is considered to be high; when Lower, or although When the compensation level is not low but mainly consists of discrete small blocks, it is determined to be limited.

[0083] Furthermore, when formulating the shape compensation evaluation index, the system can use the area overlap rate as the main criterion and whether the contact area narrows abnormally as a constraint check item; that is, only when the reverse compensation degree meets the requirements and there is no obvious narrowing of the contact area, breakage of the main load-bearing area, or abnormal increase in pressure in the middle, is the current scheme considered to meet the output conditions; through this constraint, the one-sided selection of seemingly good overlap rate but overall contact quality deteriorates can be avoided.

[0084] Furthermore, to ensure consistency in terminology, in this embodiment, the reverse deviation region and the opposite sign region are synonymous expressions of the same technical object. Both specifically refer to the region where the theoretical residual distribution and the actual residual distribution show opposite deviation directions at the same contact area position. When implementing the program, recording the results, and outputting the module interface, it is preferable to uniformly use the opposite sign region as the field name. However, the reverse deviation region can be used to describe its physical meaning when explaining the mechanism, but the two do not correspond to two different sets of judgment rules.

[0085] Furthermore, the area overlap rate, residual reverse compensation degree, and shape-correction compensation evaluation index have a fixed sequential relationship in data flow: residual comparison only produces positional correspondence results, area overlap rate only reflects the geometric proportion of dangerous areas being reverse-covered, residual reverse compensation degree is the engineering interpretation result based on area overlap rate, and shape-correction compensation evaluation index is the final criterion for closing the loop to determine whether to continue iteration; through the above hierarchical definition, it is possible to avoid directly equating area overlap rate with the final evaluation index, or mixing compensation degree with overlap rate as the same output item;

[0086] Example 2:

[0087] Please see Figure 2A wheel hub bearing system load optimization design system includes a processor and a memory. The memory stores program instructions, which, when executed by the processor, implement the method of the embodiment. The system includes: a data acquisition module for acquiring the geometric parameter set, multi-condition spatial load parameter set, and material constitutive data of the wheel hub bearing; a reference model construction module for constructing a Hertzian contact reference model and determining the reference load distribution and reference contact stress field; and a distortion correction module for correcting the distortion of the Hertzian contact reference model based on the ring structure compliance matrix and the rolling element contact skew angle model, and determining the forced distortion stress field and the ideal distortion stress field. The module defines the residual distribution; the actual residual determination module is used to determine the actual contact stress field and the actual residual distribution based on the rolling element shaping parameters and / or groove curvature parameters in the current iterative design scheme; the evaluation and decision module is used to determine the shaping compensation evaluation index based on the theoretical residual distribution and the actual residual distribution; and the closed-loop optimization module is used to output the target load-bearing optimization design scheme when the shaping compensation evaluation index meets the preset threshold condition, and to adjust the rolling element shaping parameters and / or groove curvature parameters and trigger the actual residual determination module and the evaluation and decision module to continue execution when the shaping compensation evaluation index does not meet the preset threshold condition.

[0088] This embodiment provides an implementation mechanism for a wheel hub bearing system load-bearing optimization design system. Specifically, in the aforementioned R&D scenario, method logic alone is insufficient to support repeated system calls, because design, testing, process, and material data are often scattered across different databases. Without a unified system, issues such as inconsistent parameter versions, chaotic model call order, and untraceable iteration records can easily arise in each stage. Therefore, this embodiment solidifies the method flow into an executable system.

[0089] The system can be implemented in hardware using a processor and memory, with program instructions driving the processor to complete data acquisition, benchmark modeling, distortion correction, actual residual analysis, evaluation and decision-making, and closed-loop optimization in a predetermined sequence. Alternatively, it can be implemented in a modular fashion. Specifically, the data acquisition module extracts the required inputs from the design database, test bench data interface, and material library; the benchmark model construction module generates an ideal Hertzian contact reference spectrum; the distortion correction module injects the ring compliance and contact skew into the reference model to form theoretical residuals; the actual residual determination module reconstructs the actual contact stress and forms actual residuals under the current candidate modification scheme; the evaluation and decision-making module outputs modification compensation evaluation indicators; and the closed-loop optimization module determines whether to stop iteration or continue adjusting parameters based on the evaluation results.

[0090] For ease of explanation, a complete call can be viewed as six sequentially connected data processing steps: Step 1 receives geometric, load, and material inputs; Step 2 forms the ideal contact reference; Step 3 forms the theoretical distortion result; Step 4 forms the actual compensation result; Step 5 compares the inverse overlap of the two types of results; Step 6 makes output or feedback adjustments. The advantage of this structure is that the input and output boundaries of each step are clear, which facilitates review before the design is frozen and also facilitates the subsequent writing of experimental data back to the corresponding module for correction.

[0091] In one possible implementation, the system can enter a degraded mode when any module outputs an abnormality. For example, if the compliance database on which the distortion correction module depends is temporarily unavailable, the system can output only a preliminary suggestion based on the ideal benchmark and indicate that compliance compensation analysis has not been performed. If the evaluation and decision module finds abnormal fluctuations in the index over multiple consecutive iterations, it can trigger a manual review to check for input condition conflicts or out-of-bounds candidate correction parameters.

[0092] For example, in the above-mentioned prototype development project, the system is called through the workstation. First, the current ring cross-section model, rolling element modification draft and multiple sets of combined loads are imported. Then, the system automatically generates the ideal contact reference and distortion residual diagram. The system continuously calculates three sets of candidate modification schemes and compares the actual compensation results of each scheme with the theoretical distortion results. Finally, it automatically outputs the most suitable combination of modification and groove curvature, and saves the complete iteration trajectory for the test department to make verification samples.

[0093] The purpose of this system is to engineer, streamline, and make traceable the aforementioned load-bearing optimization design method, thereby achieving closed-loop execution from parameter input to target design output.

[0094] Furthermore, to avoid confusion caused by the parallel use of module names and stage names in the system implementation, the aforementioned stages 1 to 6 are merely illustrative names for data flow that are easy to understand, and do not constitute new module names independent of the implementation. In system implementation, interface definition, log recording, and deployment configuration, it is preferable to strictly adopt the formal names in the implementation, namely, data acquisition module, benchmark model construction module, distortion correction module, actual residual determination module, evaluation and decision module, and closed-loop optimization module. This ensures that the descriptive names in the implementation correspond one-to-one with the module names in the implementation document.

[0095] Furthermore, the data transfer relationship between the above six formal modules is preferably fixed as follows: the data acquisition module outputs a unified version of the geometric parameter set, multi-condition spatial load parameter set, and material constitutive data to the benchmark model construction module; the benchmark model construction module outputs the benchmark load distribution and benchmark contact stress field to the distortion correction module and the actual residual determination module; the distortion correction module outputs the forced distortion stress field and theoretical residual distribution to the evaluation and decision module; the actual residual determination module outputs the actual contact stress field and actual residual distribution to the evaluation and decision module; the evaluation and decision module outputs the shape compensation evaluation index to the closed-loop optimization module; the closed-loop optimization module then sends the updated rolling element shape parameters and / or channel curvature parameters back to the actual residual determination module; through the above fixed interface, the reversed algorithm order or overlapping module responsibilities in the preceding and following text can be avoided;

[0096] Furthermore, to ensure complete consistency in terminology between the system implementation and the method implementation, the theoretical residual distribution, actual residual distribution, shape compensation evaluation index, and preset threshold condition in this embodiment have the same meaning as the corresponding terms in the aforementioned method embodiment, and compensation map and distortion map are not used as formal output field names; the descriptions such as theoretical distortion result illustration and actual compensation result illustration are only used for the illustration of the interface display content, and the underlying data objects still correspond to the forced distortion stress field, theoretical residual distribution, and actual residual distribution, respectively.

[0097] The data acquisition module includes: a geometric parameter acquisition unit for acquiring groove curvature parameters, rolling element shaping parameters, and initial clearance parameters; a load data acquisition unit for acquiring radial load parameters, axial load parameters, and overturning moment parameters; and a material data acquisition unit for acquiring material constitutive data, which includes elastic parameters and contact constitutive parameters.

[0098] This embodiment provides a mechanism for refining the configuration of the data acquisition module. Specifically, if the data acquisition module exists only as a general entry point, problems may easily arise during actual development, such as updated geometric parameters, outdated load versions, or the use of old material grade parameters. Especially during the prototype finalization stage, the same model often undergoes multiple rounds of groove revisions, rolling element shaping adjustments, and batch changes in heat treatment. The consistency of input directly determines the reliability of subsequent results. Therefore, this embodiment further divides the data acquisition module into three acquisition units: geometry, load, and material.

[0099] The geometric parameter acquisition unit is used to read the groove curvature parameters, rolling element shaping parameters, and initial clearance parameters. These three parameters correspond to the contact geometry, micro-compensation morphology, and initial assembly release space, respectively, and are the core basic data affecting the formation of contact spots and the order of rolling element loading. The load data acquisition unit is used to acquire the radial load parameters, axial load parameters, and overturning moment parameters, so that the inputs under different working conditions have a clear mechanical decomposition structure. The material data acquisition unit is used to acquire material constitutive data, including elastic parameters and contact constitutive parameters, in order to distinguish between changes caused by material contact response and changes caused by geometric shaping.

[0100] In practical applications, each unit can be connected to data tables from different sources. For example, geometric parameters can come from structural data exported from a 3D design system, load data can come from test benches or upstream component analysis outputs, and material data can come from heat treatment batch databases or standard material cards. In this way, when a source is modified, the system can only update the corresponding unit without affecting the version stability of other input items.

[0101] In one possible implementation, if the geometry parameter acquisition unit finds that the imported groove curvature is inconsistent with the rolling element modification version number, it can stop the current calculation and prompt for re-pairing; if the load data acquisition unit finds that only a single-direction load is provided and the overturning moment information is missing, it can allow entry into the single-condition pre-analysis mode, but prohibits the direct generation of final design recommendations; if the material data acquisition unit identifies that the material grade has changed and the contact constitutive parameters have not been updated synchronously, it marks the scheme as pending confirmation.

[0102] For example, in the later stages of the above-mentioned prototype development project, when the rolling element heat treatment regime was switched from the original scheme to the optimized scheme, resulting in changes in the contact constitutive data; at the same time, the rolling element end shaping was slightly revised; through unit data acquisition, the system can perceive geometric updates and material updates separately, and uniformly call the latest version in the same round of analysis, thereby avoiding the mixing of old material parameters and new shaping schemes.

[0103] The purpose of this mechanism is to ensure the consistency of input data in terms of source, version, and physical meaning, thereby achieving reliable management of the system's computing foundation.

[0104] The evaluation and decision module includes: a residual comparison unit, used to compare the theoretical residual distribution with the actual residual distribution; an overlap rate determination unit, used to determine the area overlap rate of regions with opposite signs based on the comparison processing results; a compensation degree determination unit, used to determine the degree of residual reverse compensation based on the area overlap rate; and a decision unit, used to determine the shape correction compensation evaluation index based on the degree of residual reverse compensation.

[0105] This embodiment provides a mechanism for refining the criteria in the evaluation decision module. Specifically, if the evaluation process only outputs a final score without breaking down its source, it is difficult to pinpoint whether the error of the current solution originates from the fact that the shaping does not cover the target distortion area, the compensation direction deviation, or the insufficient shaping amplitude. This single scoring evaluation, which lacks a description of the decision chain, is not conducive to rapid correction in prototype iteration. Therefore, this embodiment divides the evaluation decision module into four units: residual comparison, overlap rate determination, compensation degree determination, and decision.

[0106] The residual comparison unit first performs positional correspondence processing on the theoretical and actual residual distributions. Its function is to map two residual maps from different sources to the same contact area coordinates, ensuring that the comparison is of the same physical location. The overlap rate determination unit further identifies regions with opposite signs and counts the coverage of these regions in the hazardous contact area. The compensation degree determination unit then judges whether the compensation has engineering significance based on the area overlap, such as whether it only appears sporadically at the edge or forms continuous coverage of the main risk zone. The decision unit finally outputs the shape correction compensation evaluation index to drive whether to continue iteration.

[0107] The connection between these four units can be illustrated using a simplified discrete grid. Assume the contact area is discretized into six sub-regions, where the theoretical residuals are positive in the first, second, and third sub-regions, indicating a potential risk of elevation in these cells. In a certain round, the actual residuals are negative in the first and second sub-regions, but still positive in the third sub-region. At this point, the residual comparison unit completes the sub-region-by-sub-region correspondence; the overlap rate determination unit identifies the first and second sub-regions as having effective reverse overlap; the compensation degree determination unit judges that the compensation has covered the main risk areas but is not yet fully continuous; the decision unit accordingly provides a result that allows for further fine-tuning but has not yet reached the optimal level. Through this decomposition, designers can clearly identify that the next round should prioritize improving the edge region corresponding to the third cell, rather than blindly increasing the overall shape.

[0108] In one possible implementation, if the difference in the effective contact area size between two residual maps exceeds a preset size tolerance, the residual comparison unit should first indicate a contact area mismatch and not directly proceed to the overlap rate calculation; if the overlap rate is high but the compensation area is mainly concentrated in the non-dangerous area, the compensation degree determination unit should lower the evaluation result to avoid misjudgment that the area overlap rate meets the threshold condition but does not cover the core dangerous area; if the input residual map contains noisy discrete small patches, the system can first perform minimum area filtering before proceeding to the decision process to improve the evaluation stability.

[0109] For example, in the third iteration of the above prototype, the system found that although the actual residuals showed a large area of ​​decline, they were mainly distributed in the central non-dangerous area, while the high-risk zone on the stress side edge marked by the theoretical residuals was only partially covered. Through unit-by-unit judgment, it was found that the problem was not that the shaping range was insufficient, but that the shaping position and curvature transition method did not fit the edge risk zone well enough. Therefore, the next round changed the shaping focus from overall deepening to end transition optimization.

[0110] The purpose of this mechanism is to break down the shape correction compensation evaluation from a single result into an interpretable chain of judgments, thereby achieving more efficient engineering adjustment.

[0111] The closed-loop optimization module includes: a condition judgment unit, used to judge whether the shape compensation evaluation index meets the preset threshold condition; a parameter adjustment unit, used to iteratively adjust the rolling element shape parameters and groove curvature parameters according to the shape compensation evaluation index when the shape compensation evaluation index does not meet the preset threshold condition; and a result output unit, used to output the target load-bearing optimization design scheme when the shape compensation evaluation index meets the preset threshold condition.

[0112] This embodiment provides a mechanism for refining the execution of the closed-loop optimization module. Specifically, in the aforementioned system, without clear stopping conditions and parameter adjustment paths, the iterative process may encounter two types of problems: one is that the iteration terminates prematurely, resulting in the shaping not actually compensating for the distortion; the other is that the adjustment continues without constraints, leading to excessive compensation or even introducing new central compressive stress problems. Therefore, this embodiment refines the closed-loop optimization module into three units: condition judgment, parameter adjustment, and result output.

[0113] The condition judgment unit is used to determine whether the shape compensation evaluation index has reached the preset threshold condition. This threshold does not simply mean that the larger the better, but rather that the current design has formed a stable, moderate and continuous reverse compensation in the main dangerous area, while there is no obvious overcompensation. When the index is not met, the parameter adjustment unit iteratively adjusts the rolling element shape parameters and the groove curvature parameters. Generally speaking, when the system identifies that the edge peak is obvious but the central load is still stable, the rolling element end shape can be adjusted first. When the system identifies that the contact patch is too narrow or the contact axis direction is not ideal, the groove curvature parameters can be further linked to make the contact area distribution more balanced. The result output unit outputs the target load optimization design scheme after the threshold is reached, and can archive it together with the corresponding working condition coverage, contact stress characteristics and iteration records.

[0114] The closed-loop process can be illustrated using a simplified procedure. Consider three schemes: Scheme 1, Scheme 2, and Scheme 3. The evaluation result of Scheme 1 shows only localized reverse compensation at the danger edge, therefore the condition judgment unit fails the assessment. The parameter adjustment unit reshapes the rolling element end for directional reinforcement, resulting in Scheme 2. Scheme 2 shows sufficient edge compensation but a slightly narrowed central contact area, indicating an overcompensation trend. Therefore, the parameter adjustment unit stops further deepening the reshaping and instead simultaneously fine-tunes the groove curvature, resulting in Scheme 3. Scheme 3 forms continuous reverse compensation on the main risk zone, and the overall contact area remains stable. Therefore, the result output unit outputs P3 as the target scheme.

[0115] In one possible implementation, if the improvement of the evaluation index after multiple rounds of adjustments is less than the preset rate of change, the condition judgment unit can trigger a structural-level review flag, indicating that the current problem may have exceeded the compensable range of micro-modification; if a round of adjustment causes the contact area reduction rate to exceed the preset safety margin, local stress to rise again, or clearance response to be abnormal, the parameter adjustment unit should automatically revert to the previous stable scheme and reduce the parameter step size in the next round; if the maximum number of iterations is reached but the threshold is still not met, the result output unit will not output the final frozen scheme, but will output the optimal candidate scheme + pending manual confirmation status, to prevent immature designs from directly entering the mass production process;

[0116] For example, in the final development stage of the above-mentioned flanged wheel hub bearing prototype, the system successively generated multiple sets of shape modification and curvature combinations; although the first two sets of schemes reduced some edge peaks, they failed to form continuous compensation in the dangerous zone on the stress side, and therefore were not adopted; the third set of schemes formed a good synergy between the logarithmic modification of the rolling element and the curvature of the raceway, the evaluation index reached the set threshold, and no abnormal shrinkage occurred in the contact area. The system then output this set of parameters as a design recommendation, and used it for subsequent sample processing and durability verification.

[0117] The purpose of this mechanism is to establish an executable, rollbackable, and shutdownable optimization loop, thereby achieving stable convergence from candidate designs to the target-bearing optimized design scheme.

[0118] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for the optimal design of a hub bearing system load carrying, characterized in that, include: Obtain the geometric parameter set, multi-condition spatial load parameter set, and material constitutive data of the wheel hub bearing. The geometric parameter set includes at least the groove curvature parameter, rolling element modification parameter, and initial clearance parameter. Obtain the ring structure compliance matrix and the rolling element contact skew angle model. The ring structure compliance matrix characterizes the macroscopic elastic displacement mapping relationship of the wheel hub bearing under load. Under the rigid body assumption and isothermal assumption, a Hertzian contact reference model is constructed based on the geometric parameter set and the multi-condition spatial load parameter set to determine the reference load distribution and reference contact stress field. The Hertzian contact reference model is distorted based on the compliance matrix of the ring structure and the rolling element contact skew angle model. The forced distortion stress field is determined, and the theoretical residual distribution is determined based on the difference between the forced distortion stress field and the reference contact stress field. The actual contact stress field is determined based on the rolling element shaping parameters and / or groove curvature parameters in the current iterative design scheme, and the actual residual distribution is determined based on the difference between the actual contact stress field and the reference contact stress field. Based on the overlap between the theoretical residual distribution and the actual residual distribution in the reverse deviation region, the shaping compensation evaluation index is determined; The preset threshold conditions include at least the following: the area overlap rate of the opposite sign regions is greater than a preset ratio, and the peak contact stress reduction rate on the force-bearing side reaches a set value; in response to the shape compensation evaluation index meeting the preset threshold conditions, the target load-bearing optimized design scheme is output; in response to the shape compensation evaluation index not meeting the preset threshold conditions, the rolling element shape parameters and / or groove curvature parameters are iteratively adjusted according to the shape compensation evaluation index, and the actual contact stress field determination step and the shape compensation evaluation index determination step are repeatedly executed until the preset threshold conditions are met, or the preset maximum number of iterations is reached, and the current optimal candidate design scheme is output as the target load-bearing optimized design scheme.

2. The hub bearing system load optimization design method of claim 1, wherein, The load vectors in the multi-condition spatial load parameter set are defined in a preset coordinate system and include at least radial load parameters, axial load parameters, and overturning moment parameters; the material constitutive data include elastic parameters and contact constitutive parameters.

3. The hub bearing system load optimization design method of claim 1 wherein, A Hertzian contact reference model is constructed based on the geometric parameter set and the multi-condition spatial load parameter set to determine the reference load distribution and reference contact stress field, including: A Hertzian contact reference model is constructed under the assumptions of rigid body, isothermal temperature, and no manufacturing error. The Hertzian contact reference model is load-allocated based on the multi-condition spatial load parameter set to determine the reference load distribution. The reference contact stress field is determined based on the reference load distribution.

4. The hub bearing system load optimization design method of claim 1 wherein, The Hertzian contact reference model is distorted based on the compliance matrix of the ring structure and the rolling element contact skew angle model. The forced distortion stress field is determined, and the theoretical residual distribution is determined based on the difference between the forced distortion stress field and the reference contact stress field, including: Based on the structural compliance matrix of the inner and / or outer rings, calculate the radial displacement, axial displacement and tilting deformation under load; Based on the rolling element contact deflection angle model, the deflection angle of the rolling element relative to the contact normal of the raceway is calculated to obtain the contact deflection amount; The forced distortion stress field is determined based on radial displacement, axial displacement, tilt deformation, and contact deviation. The theoretical residual distribution is determined based on the positional stress difference between the forced distortion stress field and the reference contact stress field within the contact region.

5. The hub bearing system load optimization design method of claim 1 wherein, Based on the overlap between the theoretical residual distribution and the reverse deviation region in the actual residual distribution, the shaping compensation evaluation index is determined, including: By comparing the theoretical residual distribution with the actual residual distribution, the area overlap rate of the regions with opposite signs is determined; The degree of residual reverse compensation is determined based on the area overlap rate; The evaluation index for shape correction compensation is determined based on the degree of residual reverse compensation.

6. A wheel hub bearing system load-bearing optimization design system, characterized in that, The system includes a processor and a memory, the memory storing program instructions that, when executed by the processor, implement the method described in any one of claims 1 to 5; the system comprises: The data acquisition module is used to acquire the geometric parameter set, multi-condition spatial load parameter set, and material constitutive data of the wheel hub bearing; The reference model building module is used to build a Hertzian contact reference model and determine the reference load distribution and reference contact stress field. The distortion correction module is used to correct the distortion of the Hertzian contact reference model based on the compliance matrix of the ring structure and the rolling element contact skew angle model, and to determine the forced distortion stress field and theoretical residual distribution. The actual residual determination module is used to determine the actual contact stress field and the actual residual distribution based on the rolling element shaping parameters and / or groove curvature parameters in the current iterative design scheme. The evaluation and judgment module is used to determine the shaping compensation evaluation index based on the theoretical residual distribution and the actual residual distribution. The closed-loop optimization module is used to output the target load optimization design scheme when the shape compensation evaluation index meets the preset threshold conditions, and to adjust the rolling element shape parameters and / or groove curvature parameters and trigger the actual residual determination module and evaluation judgment module to continue execution when the shape compensation evaluation index does not meet the preset threshold conditions.

7. The hub bearing system load optimization design system of claim 6, wherein, The data acquisition module includes: The geometric parameter acquisition unit is used to acquire the groove curvature parameters, rolling element shaping parameters, and initial clearance parameters; The load data acquisition unit is used to acquire radial load parameters, axial load parameters, and overturning moment parameters; The material data acquisition unit is used to acquire material constitutive data, which includes elastic parameters and contact constitutive parameters.

8. The hub bearing system load optimization design system of claim 6, wherein, The evaluation and judgment module includes: The residual comparison unit is used to compare the theoretical residual distribution with the actual residual distribution. The overlap rate determination unit is used to determine the area overlap rate of regions with opposite signs based on the comparison processing results. The compensation degree determination unit is used to determine the degree of residual reverse compensation based on the area overlap rate. The decision unit is used to determine the shape correction compensation evaluation index based on the degree of residual reverse compensation.

9. The hub bearing system load optimization design system of claim 6, wherein, The closed-loop optimization module includes: The condition judgment unit is used to determine whether the shape compensation evaluation index meets the preset threshold conditions. The parameter adjustment unit is used to iteratively adjust the rolling element modification parameters and the groove curvature parameters according to the modification compensation evaluation index when the modification compensation evaluation index does not meet the preset threshold conditions. The result output unit is used to output the target load optimization design scheme when the shape compensation evaluation index meets the preset threshold conditions.

Images