Vehicle steering system load test and evaluation method and device and computer equipment

Abstract

The invention relates to a vehicle steering system load test and evaluation method and device and computer equipment. The method comprises the following steps: determining a load test object in a vehicle steering system, and calculating a theoretical load of the load test object; performing one-time finite element calculation on the load test object according to the theoretical load to obtain a theoretical working condition of the load test object; according to a preset load test model, performing finite element calculation and secondary calculation on the load test object to obtain an actual working condition of the load test object; and comparing the theoretical working condition with the actual working condition of the load test object to evaluate the vehicle steering system. By the adoption of the method, the problems that design and evaluation of the steering transmission mechanism are incomplete, and reliability is insufficient under severe working conditions can be solved, and powerful support is provided for accurate design, analysis and evaluation of the steering transmission mechanism.

Description

Technical Field

[0001] The present application relates to the technical field of automobile design and simulation testing, and in particular to a method, device and computer equipment for testing and evaluating the load of a vehicle steering system. Background Art

[0002] The vehicle steering system is a system device used to change or maintain the driving or reverse direction of the vehicle, and is an important guarantee for the safe driving of the vehicle. As a safety part on the vehicle, the reliability design of the steering system is crucial. The traditional steering system load test method is implemented through the steering system test bench, but it cannot evaluate the reliability of the steering system under actual vehicle road conditions. Summary of the invention

[0003] Based on this, it is necessary to provide a vehicle steering system load testing and evaluation method, device and computer equipment that can comprehensively consider theoretical and actual vehicle road conditions to address the above technical problems.

[0004] In a first aspect, the present application provides a vehicle steering system load testing and evaluation method. The method comprises:

[0005] Determine the load test object in the vehicle steering system and calculate the theoretical load of the load test object;

[0006] According to the theoretical load, a finite element calculation is performed on the load test object to obtain the theoretical working condition of the load test object;

[0007] According to the preset load test model, perform finite element calculation secondary calculation on the load test object to obtain the actual working condition of the load test object;

[0008] Compare theoretical and actual load test object conditions to evaluate vehicle steering systems.

[0009] In one embodiment, the load test object includes a steering transmission mechanism of a vehicle steering system or at least one transmission component in the steering transmission mechanism, and the transmission component includes a steering drop arm, a steering longitudinal tie rod, a steering knuckle upper arm, a steering knuckle, a steering knuckle lower arm and a steering transverse tie rod.

[0010] In one embodiment, the theoretical load includes a steering theoretical limit load and a driving theoretical limit load; and the calculated theoretical load of the load test object includes:

[0011] Calculate the turning load of the load test object;

[0012] According to the steering load, the steering theoretical limit load and driving theoretical limit load of the load test object are obtained.

[0013] In one embodiment, according to the theoretical load, a finite element calculation is performed on the load test object to obtain the theoretical working condition of the load test object, including:

[0014] When the load test object is a first type of test object, the theoretical working conditions of the load test object at the middle position, left turn limit and right turn limit working conditions are calculated respectively;

[0015] In the case where the load test object is a second type of test object, a theoretical driving condition and a theoretical steering condition of the load test object are calculated respectively to obtain a theoretical condition of the load test object.

[0016] In one embodiment, according to a preset load test model, a finite element calculation is performed on the load test object to obtain the actual working condition of the load test object, including:

[0017] According to the preset load test model, the stress test values ​​of multiple test points of the load test object are obtained;

[0018] According to the stress test value, the actual load of the load test object is obtained;

[0019] According to the actual load, a secondary finite element calculation is performed on the load test object to obtain the actual working condition of the load test object.

[0020] In one embodiment, comparing the theoretical working condition and the actual working condition of each load test object to evaluate the vehicle steering system includes:

[0021] Arrange and compare the theoretical and actual working conditions of the load test object;

[0022] When the calculated safety factor of the load test object does not meet the preset requirements, the load test object is optimized to meet the preset requirements.

[0023] In a second aspect, the present application also provides a vehicle steering system load testing and evaluation device. The device comprises:

[0024] A test object selection module, used to determine a load test object in a vehicle steering system;

[0025] Theoretical load calculation module, used to calculate the theoretical load of the load test object;

[0026] The finite element calculation module is used to perform a finite element calculation on the load test object according to the theoretical load to obtain the theoretical working condition of the load test object; it is also used to perform a finite element calculation on the load test object according to the preset load test model to obtain the actual working condition of the load test object;

[0027] The steering system evaluation module is used to compare the theoretical and actual operating conditions of each load test object to evaluate the vehicle steering system.

[0028] In a third aspect, the present application further provides a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of any one of the embodiments in the first aspect when executing the computer program.

[0029] In a fourth aspect, the present application further provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of any one of the embodiments in the first aspect when executed by a processor.

[0030] In a fifth aspect, the present application further provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, the steps of any embodiment of the first aspect are implemented.

[0031] The above-mentioned vehicle steering system load testing and evaluation method, device and computer equipment, through theoretical load analysis of the load test object, two finite element calculations and actual load testing, comprehensively consider theoretical working conditions and actual working conditions, improve the design and evaluation of the vehicle steering transmission mechanism, and solve the problem of insufficient reliability of the vehicle steering system load testing and evaluation method under harsh working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A diagram of an application environment of a vehicle steering system load test and evaluation method in one embodiment;

[0033] Figure 2 A schematic flow chart of a vehicle steering system load test and evaluation method in one embodiment;

[0034] Figure 3 A schematic diagram of the structure of a vehicle steering system in one embodiment;

[0035] Figure 4 A schematic diagram of a flow chart of a theoretical load including a steering theoretical limit load and a driving theoretical limit load in one embodiment; and a step of calculating a theoretical load of a load test object;

[0036] Figure 5 A schematic flow chart of the steps of performing a finite element calculation on a load test object according to a theoretical load to obtain a theoretical working condition of the load test object in one embodiment;

[0037] Figure 6 A schematic flow chart of steps for performing secondary finite element calculation on a load test object according to a preset load test model to obtain an actual working condition of the load test object in one embodiment;

[0038] Figure 7 A schematic flow chart of comparing theoretical working conditions and actual working conditions of various load test objects to evaluate the vehicle steering system steps in one embodiment;

[0039] Figure 8 A schematic flow chart of a vehicle steering system load test and evaluation method in another embodiment;

[0040] Fig. 9 A schematic diagram of stress distribution of a steering knuckle calculated by finite element calculation of theoretical load in one embodiment;

[0041] Fig.10 A schematic diagram of test points of a steering tie rod in one embodiment;

[0042] Fig.11 A schematic diagram of test points of a steering tie rod in one embodiment;

[0043] Fig.12 A schematic diagram of stress distribution of a steering knuckle calculated under actual road load conditions in one embodiment;

[0044] Fig.13 A structural block diagram of a vehicle steering system load testing and evaluation device in one embodiment;

[0045] Fig.14 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment.

[0046] Description of reference numerals:

[0047] 310, steering vertical arm; 320, steering longitudinal tie rod; 330, steering knuckle upper arm; 340, steering knuckle; 350, steering knuckle lower arm; 360, steering transverse tie rod; 370, front axle I-beam. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0049] The automobile steering system is a system device used to change or maintain the driving or reverse direction of the automobile, and is an important guarantee for the safe driving of the vehicle. The steering system mainly includes steering drop arm, steering longitudinal tie rod, steering knuckle upper arm, steering knuckle, steering knuckle lower arm and steering tie rod. When the vehicle is driving, the steering transmission mechanism bears both the steering load actively output by the steering gear and the feedback load from the road surface. The traditional measurement method uses a test bench for the steering system, based on a multi-axis sensor to detect the displacement, torque and acceleration of the steering system, which is mainly used for bench verification of the performance of the vehicle steering system, but cannot evaluate the reliability of the steering system under actual vehicle road conditions. In the design of conventional steering systems, the output load from the steering gear and the steering resistance torque from the road surface are often concerned, while the feedback of other loads from complex road surfaces is ignored. Especially under harsh road conditions, the load reacting to the steering transmission mechanism may cause direct damage to the components. Therefore, for the vehicle steering system, a set of steering system reliability evaluation methods that comprehensively consider theory and actual vehicle road conditions are needed.

[0050] The vehicle steering system load testing and evaluation method provided in the embodiment of the present application can be applied to Figure 1 In the application environment shown. The load test device 102 communicates with the terminal 104 through the network. The load test device 102 obtains the test data of the load test object, and the terminal 104 processes the test data of the load test object to evaluate the vehicle steering system. The terminal 104 can be, but is not limited to, various personal computers, laptops, smart phones, tablet computers, Internet of Things devices and portable wearable devices. The Internet of Things devices can be smart speakers, smart TVs, smart air conditioners, smart car-mounted devices, etc. Portable wearable devices can be smart watches, smart bracelets, head-mounted devices, etc.

[0051] In an exemplary embodiment, Figure 2 As shown, a vehicle steering system load test and evaluation method is provided, and the method is applied to Figure 1 The terminal 104 in the example is used as an example to illustrate, and the following steps are included:

[0052] Step 202: determine a load test object in a vehicle steering system, and calculate a theoretical load of the load test object.

[0053] Optionally, there are multiple transmission components in the vehicle steering system, and the test methods of each transmission component are not completely consistent, so it is necessary to determine the load test object and select the corresponding measurement method. After determining the load test object, perform theoretical load analysis on the load test object to calculate the theoretical load of the load test object.

[0054] For example, the vehicle steering system mainly includes the steering drop arm, the steering longitudinal tie rod, the steering knuckle upper arm, the steering knuckle, the steering knuckle lower arm and the steering tie rod. The force on the steering knuckle is relatively complex, bearing the force from the steering longitudinal tie rod and the steering tie rod, as well as the force from the wheels. Therefore, it is necessary to determine the object of analysis and evaluation. If the entire steering transmission mechanism or the steering knuckle is analyzed, the force analysis of the entire system is required.

[0055] Step 204 , performing a finite element calculation on the load test object according to the theoretical load, and obtaining a theoretical working condition of the load test object.

[0056] Alternatively, finite element calculation is a numerical analysis method mainly used for structural analysis in engineering and physics. It is a method to approximate the solution of physical field problems (such as stress, temperature, fluid flow, etc.) by discretizing continuous media or objects with complex geometric shapes into a finite number of sub-regions (i.e. elements). Based on the theoretical load of the load test object, a finite element calculation is performed on the load test object once, and the theoretical stress distribution of the load test object under various working conditions can be obtained, thereby obtaining its theoretical working conditions.

[0057] Step 206 , performing a secondary finite element calculation on the load test object according to the preset load test model to obtain the actual working condition of the load test object.

[0058] Optionally, the stress load of the load test object under actual road conditions is calculated according to a preset load test model corresponding to the load test object; based on the stress load under actual road conditions, a secondary finite element calculation is performed to obtain the actual stress distribution under various working conditions, thereby obtaining the actual working condition of the load test object.

[0059] Step 208 : comparing the theoretical working condition and the actual working condition of the load test object to evaluate the vehicle steering system.

[0060] Optionally, a comparison table is established based on theoretical working conditions and actual working conditions of the load test object, and the vehicle steering system is evaluated with reference to the design requirements of the load test object, and improvements are made to the test object that does not meet the design requirements.

[0061] The above-mentioned vehicle steering system load test and evaluation method, through theoretical load analysis of the load test object, two finite element calculations and actual load testing, comprehensively considers theoretical working conditions and actual working conditions, improves the design and evaluation of the vehicle steering transmission mechanism, and improves the reliability of the vehicle steering system load test and evaluation method under harsh working conditions to ensure vehicle driving safety.

[0062] In an exemplary embodiment, Figure 3As shown, the load test object includes a steering transmission mechanism of a vehicle steering system 300 or at least one transmission component in the steering transmission mechanism, and the transmission component includes a steering drop arm 310, a steering longitudinal tie rod 320, a steering knuckle upper arm 330, a steering knuckle 340, a steering knuckle lower arm 350 and a steering transverse tie rod 360. Figure 3 Also included is a front axle I-beam 370.

[0063] For example, the vehicle steering system load test and evaluation method of the present application can analyze a single transmission component in the vehicle steering system separately, such as testing the load of the steering longitudinal tie rod 320 on a complex road surface separately and evaluating its performance; it can also analyze a combination of several transmission components of the vehicle steering system, such as the combination of the steering longitudinal tie rod 320 and the steering transverse tie rod 360; it can also analyze the entire vehicle steering system to evaluate the vehicle steering system and optimize and improve the weak structure that does not meet the design requirements. Due to different measurement parameters of each transmission component, its load test method is also adjusted accordingly.

[0064] The following embodiments specifically illustrate the manner in which the present application implements the steering system load test.

[0065] In an exemplary embodiment, Figure 4 As shown, the theoretical load includes the steering theoretical limit load and the driving theoretical limit load; the steps of calculating the theoretical load of the load test object include:

[0066] Step 402: Calculate the steering load of the load test object.

[0067] Step 404: Obtain the steering theoretical limit load and driving theoretical limit load of the load test object according to the steering load.

[0068] For example, the steering load and driving load are calculated theoretically. The steering transmission mechanism mainly bears the steering load. The steering load of each component on the steering transmission mechanism can be calculated based on the output torque of the steering gear, the relevant parameters of the steering transmission mechanism and the front axle; the driving load borne by the steering knuckle can be calculated based on the parameters of the whole vehicle and the front axle. The theoretical steering limit loads under different steering positions are sorted out: the middle position, the left turn limit and the right turn limit; the theoretical driving limit loads under driving conditions are sorted out: the impact condition, the side slip condition and the braking condition.

[0069] In this embodiment, by using different parameters and test methods for different load test objects, the steering theoretical limit load and driving theoretical limit load of each load test object can be accurately calculated, thereby ensuring the reliability of the steering system load test and evaluation method.

[0070] In an exemplary embodiment, Figure 5As shown, according to the theoretical load, the finite element calculation is performed on the load test object once, and the steps of obtaining the theoretical working condition of the load test object include:

[0071] Step 502 , when the load test object is a first type of test object, respectively calculate theoretical working conditions of the load test object under the middle position, left turn limit and right turn limit working conditions.

[0072] Exemplarily, the first type of test objects include a steering drop arm 310, a steering longitudinal tie rod 320, a steering knuckle upper arm 330, a steering knuckle lower arm 350, and a steering tie rod 360. For the steering drop arm 310, the steering longitudinal tie rod 320, the steering knuckle upper arm 330, the steering knuckle lower arm 350, and the steering tie rod 360, one end of the component can be constrained, and a theoretical limit load is applied to the other end, and the stress distribution of each component under the middle position, left turn limit, and right turn limit working conditions is calculated respectively, and the stress values ​​of the calibrated points of the steering longitudinal tie rod 320 and the steering tie rod 360 are counted to obtain the theoretical working conditions under the middle position, left turn limit, and right turn limit working conditions of the load test object.

[0073] Step 504 , when the load test object is a second type of test object, respectively calculate the theoretical driving condition and the theoretical steering condition of the load test object to obtain the theoretical condition of the load test object.

[0074] Exemplarily, the second type of test object includes a steering knuckle 340. For the steering knuckle, the kingpin end can be constrained, and the driving load can be applied to the wheel end bearing to calculate the theoretical driving condition; the wheel end bearing can be constrained, and the steering limit load can be applied to the steering knuckle upper arm 330 and the steering knuckle lower arm 350 to calculate the theoretical steering condition, and obtain the theoretical condition of the load test object.

[0075] In the above embodiment, by taking targeted finite element one-time calculations for different load test objects, the theoretical working conditions of each load test object can be accurately and efficiently obtained to ensure the reliability of the steering system evaluation.

[0076] In an exemplary embodiment, Figure 6 As shown, according to the preset load test model, the steps of performing finite element calculation secondary calculation on the load test object to obtain the actual working condition of the load test object include:

[0077] Step 602: Obtain stress test values ​​of multiple test points of the load test object according to a preset load test model.

[0078] For example, the two ends of the steering longitudinal tie rod 320 and the steering transverse tie rod 360 are connected by ball heads, and the preset load test model is a standard two-force rod model, which does not bear torque, and the force direction is along the line connecting the two ends of the ball heads. The physical model is relatively simple, so the actual force of the steering transmission mechanism in actual driving is confirmed by testing the steering longitudinal tie rod 320 and the steering transverse tie rod 360. Since the steering longitudinal tie rod 320 is generally not a straight rod, there is a certain error in the point calibration. Therefore, considering the influencing factors of the actual test, multiple test points are used to measure the stress test value. For example, the 6-point test method is used here to perform the load test. Three points are calibrated on the steering longitudinal tie rod 320, two of which are located at the two ends of the steering longitudinal tie rod 320, and the third point is at the maximum stress point of the steering longitudinal tie rod 320 finite element calculation. Three points are calibrated on the steering transverse tie rod 360, two of which are located at the two ends of the steering transverse tie rod 360, and the third point is in the middle of the steering transverse tie rod 360. The stress-strain testing equipment is used to test the stress-time history of the above six points at the test site or user site.

[0079] Step 604: Obtain the actual load of the load test object according to the stress test value.

[0080] For example, the stress test values ​​of the six calibration points are statistically recorded, and a table of point-theoretical load-finite element calculated stress value-test stress value is established according to the corresponding relationship. Through their proportional relationship, the actual force on the steering longitudinal tie rod 320 and the steering transverse tie rod 360 is inversely calculated. According to the force values ​​inversely calculated from the three points on the steering longitudinal tie rod 320, the average value is taken to obtain the actual force of the steering longitudinal tie rod 320, and any abnormal data is removed during the calculation; according to the force values ​​inversely calculated from the three points on the steering transverse tie rod 360, the average value is taken to obtain the actual force of the steering transverse tie rod 360, and any abnormal data is removed during the calculation.

[0081] Step 606: Perform finite element secondary calculation on the load test object according to the actual load to obtain the actual working condition of the load test object.

[0082] For example, according to the actual load under actual road conditions, the stress distribution of the steering transmission mechanism is calculated. For the steering drop arm 310, the steering longitudinal tie rod 320, the steering knuckle upper arm 330, the steering knuckle lower arm 350 and the steering tie rod 360, one end of the component can be constrained, and the actual load is applied to the other end to calculate their actual stress distribution and obtain the actual working condition of the above load test object. For the steering knuckle 340, the wheel end bearing is constrained, and the actual load is applied to the steering knuckle upper arm and the steering knuckle lower arm, and the actual stress distribution is calculated to obtain the actual working condition of the steering knuckle 340.

[0083] In the above embodiment, a preset load test model is used to accurately measure the stress test values ​​of multiple test points of the load test object. For the non-straight steering longitudinal tie rod 320 and the steering transverse tie rod 360, a 6-point test method is used to perform load testing, and the actual force is inversely calculated based on the stress test value, and the actual working condition of the load test object is accurately obtained through secondary finite element calculation; an overall load test plan is proposed, and a corresponding table of point-theoretical load-finite element calculated stress value-test stress value is established to effectively obtain the actual force of the steering transmission mechanism at the test site or user site, thereby providing support for the reliability evaluation of the steering system.

[0084] The following embodiments specifically illustrate the method of steering system load evaluation of the present application.

[0085] In an exemplary embodiment, Figure 7 As shown, the steps of comparing the theoretical working conditions and actual working conditions of each load test object to evaluate the vehicle steering system include:

[0086] Step 702: Arrange and compare the theoretical working condition and the actual working condition of the load test object.

[0087] Step 704, when the calculated safety factor of the load test object does not meet the preset requirement, the load test object is optimized to meet the preset requirement.

[0088] For example, the calculation results of theoretical load and actual load are sorted out, the theoretical working conditions and actual working conditions of the load test object are compared, and the actual force on the steering mechanism during actual driving is analyzed, especially the large feedback force of the road surface on the steering mechanism under severe road conditions, so that the calculated safety factors of each component of the steering transmission mechanism meet the specified requirements, otherwise the weak structure is optimized and improved.

[0089] In the above embodiment, by being able to handle the large feedback force of the road surface on the steering mechanism under severe actual road conditions, the problems of insufficient reliability of the steering transmission mechanism and damage under severe working conditions can be solved.

[0090] The present invention will be described in further detail below by taking the analysis of a steering knuckle in a certain vehicle steering system as an example and in conjunction with the accompanying drawings.

[0091] In an exemplary embodiment, Figure 8 As shown, another vehicle steering system load test and evaluation method is provided, the method steps comprising:

[0092] Step 802, determine the load test object.

[0093] For example, the object of analysis and evaluation is determined to be the steering knuckle 340 in the steering system. The steering power of the steering gear is transmitted to the steering knuckle 340 through the steering vertical arm 310, the steering longitudinal tie rod 320 and the steering knuckle upper arm 330, and is transmitted to the steering knuckle 340 at the other end through the steering knuckle lower arm 350 and the steering tie rod 360, so that the wheel assembled on the steering knuckle 340 can be steered. Therefore, to analyze and evaluate the steering knuckle 340, it is necessary to consider the load on the steering longitudinal tie rod 320, the load on the steering tie rod 360, and the impact, side slip and braking load during driving, so it is necessary to perform force analysis on the entire system.

[0094] Step 804, calculate and analyze the theoretical load, and perform a finite element calculation.

[0095] For example, the maximum effective output torque of the steering gear is 7000Nm. According to the parameters of the whole vehicle and the front axle, the driving load borne by the steering knuckle 340 is calculated; according to the relevant parameters of the steering transmission mechanism and the front axle, the steering load borne by each component of the steering transmission mechanism is calculated; the theoretical limit loads under driving conditions are sorted out: impact conditions, side slip conditions and braking conditions, and the driving condition load acts on the wheel contact point; the theoretical limit loads under different steering positions are sorted out: the middle position, the left turn limit and the right turn limit, and the steering condition load acts on the steering transmission mechanism.

[0096] Impact conditions:

[0097] The calculation formula of wheel vertical impact load is:

[0098]

[0099] in, Indicates the left wheel impact load, unit N; Indicates the right wheel impact load, unit N; It represents the dynamic load coefficient; Indicates the front axle load when fully loaded, in N.

[0100] Side sliding condition:

[0101] The calculation formula of wheel vertical impact load is:

[0102]

[0103]

[0104] The wheel lateral load calculation formula is:

[0105]

[0106]

[0107] in, Indicates the vertical load on the left wheel in the side slip condition, in N; Indicates the vertical load on the right wheel in the side slip condition, in N; Indicates the left wheel lateral load, unit N; Indicates the right wheel lateral load, unit N;

[0108] It represents the road adhesion coefficient; Indicates the height of the vehicle's center of mass from the ground, in mm; Indicates the front wheel track in mm.

[0109] Braking conditions:

[0110] The calculation formula of wheel vertical impact load is:

[0111]

[0112] The wheel brake load calculation formula is:

[0113]

[0114] in, Indicates the vertical load on the left wheel under braking condition, in N; Indicates the vertical load on the right wheel under braking condition, in N; Indicates the distance from the center of mass of the vehicle to the rear axle, in mm; Indicates the left wheel brake load, unit N; Indicates the right wheel brake load, unit: N.

[0115] Steering conditions:

[0116] The calculation formula of the left wheel steering resistance torque is:

[0117]

[0118] The load calculation formula applied to the steering knuckle upper arm 330 (steering trailing rod 320) is:

[0119]

[0120] The load applied to the steering knuckle lower arm 350 (steering tie rod 360) is calculated as follows:

[0121]

[0122] in, Indicates the steering resistance torque of the left wheel, in Nmm; It represents the sliding friction coefficient between the tire and the road surface; p represents the tire pressure, in MPa; represents the load applied to the steering knuckle upper arm 330, in N; Indicates the maximum output load of the steering gear, in Nmm; It represents the effective force arm of the steering longitudinal tie rod 320 relative to the steering gear output shaft, in mm; represents the load applied to the steering knuckle lower arm 350, in N; It represents the effective force arm of the steering longitudinal tie rod 320 relative to the kingpin axis of the steering knuckle 340, in mm; It represents the effective force arm of the steering tie rod 360 relative to the kingpin axis of the steering knuckle 340, in mm.

[0123] The object of finite element analysis is the steering knuckle 340. The steering knuckle 340, the steering knuckle upper arm 330 and the steering knuckle lower arm 350 can be assembled together for calculation. The steering knuckle 340 is constrained at the wheel end mounting bearing, and steering loads of the middle position, left turn limit and right turn limit are applied to the ends of the steering knuckle upper arm 330 and the steering knuckle lower arm 350 to calculate the stress distribution of the steering knuckle 340 under steering conditions. The steering knuckle 340 is constrained at the main pin shaft, and the calculated loads of impact conditions, side slip conditions and braking conditions are applied to the wheel contact point to calculate the stress distribution of the steering knuckle 340 under driving conditions. For the steering longitudinal tie rod 320 and the steering transverse tie rod 360, a two-force rod physical model is established, and the limit load calculated for the steering condition at the middle position is applied to calculate the stress distribution of the steering longitudinal tie rod 320 and the steering transverse tie rod 360. The stress distribution of the steering knuckle 340 calculated by finite element under theoretical load is as follows Fig. 9 As shown, it occurs in the side slip condition.

[0124] Step 806, test and extract the actual load, and perform finite element secondary calculation.

[0125] For example, the steering longitudinal tie rod 320 and the steering transverse tie rod 360 are patched by strain testing equipment to test the stress parameters of the calibration points to confirm the actual force of the steering transmission mechanism during actual driving. The six-point test method is used for load testing. Fig.10 and Fig.11 As shown, three points a, b, and c are marked on the steering longitudinal tie rod 320, where a and b are located at the two ends of the steering longitudinal tie rod 320, with a distance of La and Lb, and c is located at the maximum calculated stress point of the finite element calculation of the steering longitudinal tie rod 320. Three points d, e, and f are marked on the steering transverse tie rod 360, where d and e are located at the two ends of the steering transverse tie rod 360, with a distance of Ld and Le, and f is located in the middle of the steering transverse tie rod 360. The stress-time history of the above six points at the test site or the user site is tested by the stress-strain testing equipment.

[0126] The stress test values ​​of the six calibration points a, b, c, d, e and f are statistically recorded, and a table of point-theoretical load-finite element calculated stress value-tested stress value is established according to the corresponding relationship. Through their proportional relationship, the actual force on the steering longitudinal tie rod 330 and the steering transverse tie rod 360 is inversely calculated. The average force of points a, b and c on the steering longitudinal tie rod 320 is taken, and the actual force of the steering longitudinal tie rod 320 is 36433N; the average force of points d, e and f on the steering transverse tie rod 360 is taken, and the actual force of the steering transverse tie rod 360 is 80107N.

[0127] According to the load under actual road conditions, the stress distribution of the steering knuckle 340 is calculated. The actual road load extracted above is applied to the ends of the steering knuckle upper arm 330 and the steering knuckle lower arm 350 at the wheel end of the steering knuckle 340. The steering knuckle upper arm 330 is applied with a load of 36433N, and the direction is along the line connecting the two ends of the ball heads of the longitudinal tie rod 320. The steering knuckle lower arm 350 is applied with a load of 80107N, and the direction is along the line connecting the two ends of the ball heads of the lateral tie rod 360. The stress distribution calculated by the actual road load is as follows: Fig.12 shown.

[0128] Step 808 , comparing the theoretical operating conditions with the actual operating conditions, and evaluating the vehicle steering system as a whole.

[0129] For example, the calculation results of theoretical load and actual load are sorted out, and the theoretical working conditions are compared with the actual working conditions. The calculated maximum stress of the steering knuckle 340 under the theoretical load is 583MPa, and the safety factor is 1.35; the calculated maximum stress under the actual road load is 759MPa, and the safety factor is 1.03. It can be seen that the actual road conditions have a great influence on the reliability of the steering knuckle 340, and in the structural design, targeted optimization and improvement of weak areas are required.

[0130] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0131] Based on the same inventive concept, the embodiment of the present application also provides a vehicle steering system load test and evaluation device for implementing the vehicle steering system load test and evaluation method involved above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above method, so the specific limitations in one or more vehicle steering system load test and evaluation device embodiments provided below can refer to the limitations of the vehicle steering system load test and evaluation method above, and will not be repeated here.

[0132] In an exemplary embodiment, Fig.13 As shown, a vehicle steering system load test and evaluation device is provided, including: a test object selection module 1310, a theoretical load calculation module 1320, a finite element calculation module 1330 and a steering system evaluation module 1340, wherein:

[0133] The test object selection module 1310 is used to determine the load test object in the vehicle steering system.

[0134] The theoretical load calculation module 1320 is used to calculate the theoretical load of the load test object.

[0135] The finite element calculation module 1330 is used to perform a finite element calculation on the load test object according to the theoretical load to obtain the theoretical working condition of the load test object; it is also used to perform a finite element calculation on the load test object according to a preset load test model to obtain the actual working condition of the load test object.

[0136] The steering system evaluation module 1340 is used to compare the theoretical working conditions and the actual working conditions of each load test object to evaluate the vehicle steering system.

[0137] In an exemplary embodiment, the theoretical load calculation module 1320 is also used to calculate the steering load of the load test object; according to the steering load, the steering theoretical limit load and the driving theoretical limit load of the load test object are obtained.

[0138] In an exemplary embodiment, the finite element calculation module 1330 further includes:

[0139] The finite element primary calculation module is used to calculate the theoretical working conditions of the load test object under the middle position, left turn limit and right turn limit conditions when the load test object is a first type of test object; when the load test object is a second type of test object, the theoretical driving condition and theoretical steering condition of the load test object are calculated to obtain the theoretical working conditions of the load test object.

[0140] In an exemplary embodiment, the finite element calculation module 1330 further includes:

[0141] The finite element secondary calculation module is used to obtain the stress test values ​​of multiple test points of the load test object according to the preset load test model; obtain the actual load of the load test object according to the stress test values; and perform finite element secondary calculation on the load test object according to the actual load to obtain the actual working condition of the load test object.

[0142] In an exemplary embodiment, the steering system evaluation module 1340 is also used to organize and compare the theoretical working conditions and actual working conditions of the load test object; when the calculated safety factor of the load test object does not meet the preset requirements, the load test object is optimized to meet the preset requirements.

[0143] Each module in the above-mentioned vehicle steering system load test and evaluation device can be implemented in whole or in part by software, hardware and a combination thereof. Each of the above-mentioned modules can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute the operations corresponding to each of the above modules.

[0144] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as follows: Fig.14 As shown. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface, the display unit and the input device are connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and the external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be realized through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a vehicle steering system load test and evaluation method is realized. The display unit of the computer device is used to form a visually visible picture, which can be a display screen, a projection device or a virtual reality imaging device. The display screen can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad set on the computer device shell, or an external keyboard, touchpad or mouse.

[0145] Those skilled in the art will understand that Fig.14The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0146] In an exemplary embodiment, a computer device is further provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above-mentioned method embodiments when executing the computer program.

[0147] In an exemplary embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0148] In an exemplary embodiment, a computer program product is provided, including a computer program, and when the computer program is executed by a processor, the steps in the above method embodiments are implemented.

[0149] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant laws, regulations and standards of relevant countries and regions.

[0150] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0151] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0152] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A vehicle steering system load test and evaluation method, characterized in that: The method comprises: Determining a load test object in a vehicle steering system, and calculating a theoretical load of the load test object; According to the theoretical load, a finite element calculation is performed on the load test object to obtain a theoretical working condition of the load test object; According to the preset load test model, a finite element calculation is performed on the load test object to obtain the actual working condition of the load test object; The theoretical operating conditions and actual operating conditions of the load test object are compared to evaluate the vehicle steering system.

2. The vehicle steering system load testing and evaluation method according to claim 1, characterized in that: The load test object includes the steering transmission mechanism of the vehicle steering system or at least one transmission component in the steering transmission mechanism, and the transmission component includes a steering drop arm, a steering longitudinal tie rod, a steering knuckle upper arm, a steering knuckle, a steering knuckle lower arm and a steering transverse tie rod.

3. The vehicle steering system load testing and evaluation method according to claim 1, characterized in that: The theoretical load includes a steering theoretical limit load and a driving theoretical limit load; Calculating the theoretical load of the load test object includes: calculating a steering load of the load test object; The steering theoretical limit load and the driving theoretical limit load of the load test object are obtained according to the steering load.

4. The vehicle steering system load testing and evaluation method according to claim 1, characterized in that: The performing a finite element calculation on the load test object according to the theoretical load to obtain the theoretical working condition of the load test object comprises: When the load test object is a first type of test object, respectively calculating theoretical working conditions of the load test object at a middle position, a left turn limit and a right turn limit working conditions; In the case that the load test object is a second type of test object, the theoretical driving condition and the theoretical steering condition of the load test object are calculated respectively to obtain the theoretical condition of the load test object.

5. The vehicle steering system load testing and evaluation method according to claim 1, characterized in that: The performing finite element calculation secondary calculation on the load test object according to the preset load test model to obtain the actual working condition of the load test object comprises: According to the preset load test model, obtaining stress test values ​​of multiple test points of the load test object; According to the stress test value, obtaining the actual load of the load test object; According to the actual load, a secondary finite element calculation is performed on the load test object to obtain the actual working condition of the load test object.

6. The vehicle steering system load testing and evaluation method according to claim 1, characterized in that: The comparing the theoretical working conditions and the actual working conditions of each load test object to evaluate the vehicle steering system includes: Arrange and compare the theoretical working conditions and actual working conditions of the load test object; When the calculated safety factor of the load test object does not meet the preset requirements, the load test object is optimized to meet the preset requirements.

7. A vehicle steering system load testing and evaluation device, characterized in that: The device comprises: A test object selection module, used to determine a load test object in a vehicle steering system; A theoretical load calculation module, used to calculate the theoretical load of the load test object; A finite element calculation module is used to perform a finite element calculation on the load test object according to the theoretical load to obtain the theoretical working condition of the load test object; and is also used to perform a finite element calculation on the load test object according to a preset load test model to obtain the actual working condition of the load test object; The steering system evaluation module is used to compare the theoretical working conditions and actual working conditions of each load test object to evaluate the vehicle steering system.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the vehicle steering system load testing and evaluation method according to any one of claims 1 to 6 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the vehicle steering system load testing and evaluation method according to any one of claims 1 to 6 are implemented.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the vehicle steering system load testing and evaluation method according to any one of claims 1 to 6 are implemented.

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