Shock absorber cumulative risk monitoring and adaptive adjustment method

Abstract

The application provides a shock absorber cumulative risk monitoring and adaptive adjustment method, comprising: performing simulation calculation consistent with actual road test requirements to obtain result data; obtaining front and rear axle equivalent speeds according to the result data; matching the front and rear axle equivalent speeds with preset shock absorber characteristic speed nodes, calculating a fusion weight mapped to a corresponding speed node at each simulation step; defining a risk factor, calculating a dimensionless exceeding proportion of each risk factor at each simulation step; calculating a risk value according to the fusion weight and the dimensionless exceeding proportion, and accumulating risk values corresponding to each speed node at all simulation times; setting a reference damping force amplification multiple and a change range, determining an adjustment coefficient of each speed node based on the accumulated risk, mapping the adjustment coefficient to a damping force of a corresponding speed node of an original shock absorber characteristic by using proportional control, and obtaining an optimized front and rear shock absorber characteristic.

Description

Technical Field

[0001] This invention relates to the technical field of virtual testing for automobiles, and more specifically, to a method for monitoring and adaptively adjusting the cumulative risk of shock absorbers. Background Technology

[0002] With the rapid development of the automotive industry, the generally shortened development cycle has placed higher demands on the quality control of vehicle development in the early stages. Virtual simulation technology, as a key measure to quickly verify various performance indicators of vehicles during the project development phase, is a key method to avoid development risks, evaluate product performance, and optimize and iterate various performance indicators. Excellent virtual simulation calculation methods can effectively reduce testing costs and improve product reliability at different stages of the vehicle development cycle.

[0003] As a core component of the chassis suspension system, the shock absorber is crucial for stabilizing vehicle posture, improving the vehicle's adaptability to complex terrain, preventing large impact collisions, enhancing vehicle passability, effectively isolating vibrations from road surface excitation, and ensuring that vehicle acceleration meets the physiological and psychological expectations of human comfort regarding vibration. Since the two key performance indicators of vehicle comfort and passability have different requirements for the damping force of the shock absorber at different speed ranges, the damping force of the shock absorber is a key parameter for evaluating vehicle driving safety and comfort.

[0004] Currently in the automotive field, adjusting the damping force of shock absorbers requires target decomposition based on the vehicle's performance parameters. Adjustable prototypes are used to quickly verify the design scheme, thereby obtaining a characteristic curve that balances multiple objectives such as comfort, handling, and passability. Multiple iterative optimizations are then performed. While subjectively evaluating comfort, requirements for vehicle stability must also be met. Furthermore, in actual engineering, the requirements for comfort and passability vary under different driving conditions. Therefore, optimizing the characteristics of shock absorbers to accommodate different operating conditions is crucial. Moreover, when driving under extreme conditions, maintaining vehicle stability is essential for driving safety, and the damping force of the shock absorber at different speed ranges has different effects on passability and comfort. Current engineering practices consider using active shock absorbers instead of traditional ones, switching between different operating modes based on the selected driving mode to meet the user's current driving needs. However, active shock absorber systems are complex, requiring the coordinated operation of multiple modules such as sensors, controllers, and actuators. Electronic failures can lead to functional degradation or even loss, while also increasing development costs. For traditional shock absorbers, increasing the damping force across the entire speed range during severe collisions in road tests can significantly affect the overall vehicle comfort. Therefore, further in-depth research and widespread attention are needed to optimize and iterate the damping force of traditional shock absorbers. Summary of the Invention

[0005] This invention provides a method for monitoring and adaptively adjusting the cumulative risk of a shock absorber, aiming to solve the problems of existing shock absorber adjustment methods relying on subjective experience, difficulty in accurately locating the risk speed operating point, and difficulty in balancing comfort and passability, thereby improving the accuracy and efficiency of shock absorber adjustment.

[0006] To achieve the above objectives, the present invention provides a method for monitoring and adaptively adjusting the cumulative risk of a vibration damper, the method comprising the following steps: Step S1: Use multibody dynamics simulation software to build the models of each subsystem and the whole vehicle multibody model; process the actual road test road surface model, determine the road surface resolution and driving center line, determine the driving speed, perform simulation calculations consistent with the actual road test requirements, and obtain the result data; Step S2: Based on the result data, obtain the velocity data of four vibration dampers in the time domain, front and rear, and calculate the average velocity of the vibration dampers on the left and right sides of the front and rear axles point by point to obtain the equivalent velocity of the front and rear axles; match the equivalent velocity with multiple velocity nodes obtained by discretizing the original vibration damper characteristic data, and calculate the fusion weight mapped to the corresponding velocity node at each simulation time according to the distance and positional relationship between the equivalent velocity value and the velocity node; Step S3: Define risk factors, which include at least pitch angle, pitch rate, and equivalent speeds of the front and rear axes; set a threshold for each risk factor, and calculate the dimensionless overshoot ratio of each risk factor at each simulation time; calculate the risk value based on the fusion weight and the dimensionless overshoot ratio, and accumulate the risk values ​​corresponding to each speed node at all simulation times to obtain the cumulative risk. Step S4: Set the reference damping force amplification factor and variation range, determine the adjustment coefficient of each speed node based on the accumulated risk, and use proportional control to map the adjustment coefficient to the damping force of the speed node corresponding to the original shock absorber characteristics to obtain the optimized front and rear shock absorber characteristics.

[0007] In one embodiment, the result data includes at least the time-domain result data of the damper speed, pitch angle, and pitch angular velocity.

[0008] In one embodiment, step S2 specifically includes: Step S21: Based on the result data, obtain the speed data of four shock absorbers in the time domain of the result data, calculate the average speed of the shock absorbers on the left and right sides of the front and rear axles point by point, and obtain the equivalent speed of the front and rear axles. Step S22: Based on step S21, scan the equivalent velocity of the front and rear axle dampers at each step in the simulation time domain, compare it with all velocity nodes in the damper characteristic data, and obtain the velocity nodes and node positions that match the equivalent velocity. When the vibration damper characteristic data contains the equivalent velocity at the current simulation moment, in order to achieve accurate matching, the equivalent velocity value and its position in the characteristic data are used as the velocity node and node position. When the damper characteristic data does not contain the equivalent velocity of the current simulation step, for approximate matching, the maximum value of the characteristic data that is less than the equivalent velocity and the minimum value that is greater than the equivalent velocity are selected, and their equivalent velocity values ​​and positions are determined as velocity nodes and node positions respectively. Step S23: Based on the speed nodes and node positions matched in the characteristics of the front and rear dampers obtained in steps S21 and S22, calculate the fusion weight mapped to the corresponding node at each simulation moment. When it is an exact match, the fusion weight of the matching node is set to 1; When approximating the speed, if the equivalent speed exceeds the range of the original damper characteristic data, the fusion weight of the mapped limit speed node is set to 1. When the approximate match is achieved and the equivalent speed is located between the speed nodes of the original damper characteristic data, the distance weight is calculated based on the inverse ratio of the equivalent speed to the distance between these two speed nodes. Simultaneously, the position weight is calculated based on the cube of the speed value of the characteristic speed node to increase the weight of the high-speed segment. The distance weight and the position weight are weighted and fused to obtain the fused weights mapped to these two speed nodes respectively.

[0009] In one embodiment, in step S21, the equivalent speeds of the front and rear axles... The specific calculation formula is as follows:

[0010] in, For simulation time, This represents the total number of simulation steps. , , , These are the front left shock absorber, front right shock absorber, rear left shock absorber, and rear right shock absorber, respectively. The velocity value at that moment. For the front axle shock absorber in the first The equivalent velocity at any given moment. For the rear axle vibration damper in the first The equivalent velocity at any given moment.

[0011] In one embodiment, step S22, determining the velocity node and its position as the velocity node and node position specifically includes: ,in , ; in, The original vibration damper speed data, These correspond to the front and rear equivalent vibration damper data, respectively. for The first in One speed data point, For the equivalent vibration damper data The velocity value at each moment; To screen out Less than in the array The maximum value; for exist In the middle position, when Less than When all values ​​in the array are present, and Empty; To screen out array greater than The minimum value, for exist In the middle position, when Greater than When all values ​​in the array are present, and Empty; when , ; when , ; when , ; when and , , ; in For the first At that moment, according to the equivalent damper data Obtained vibration damper characteristics The speed nodes and node positions matched in the middle.

[0012] In one embodiment, step S23, the fusion weight calculation method specifically includes:

[0013] when When the array length is equal to 2, that is None of them are empty;

[0014] The specific calculation of the fusion weight for the first velocity node is as follows:

[0015] The specific calculation of the fusion weight for the second velocity node is as follows: ; when When the array length is equal to 1, that is... Empty, or Empty; The specific calculation of the fusion weight for the corresponding velocity node is as follows: .

[0016] In one embodiment, step S3 specifically includes: Step S31: Define risk factors, which include pitch angle, pitch angular velocity, and equivalent velocity values ​​of the front and rear axles of the shock absorber obtained in step S21. Step S32: Define the threshold for each risk factor based on step S31: For the equivalent velocity values ​​of the front and rear shafts of the shock absorber, the tension section and compression section of the shock absorber are distinguished according to the positive and negative values ​​of the equivalent velocity values, and the average value of all tension section velocity values ​​and the average value of all compression section velocity values ​​in the simulation are used as thresholds respectively. For the pitch angle and pitch velocity, the mean of the absolute values ​​of all data within the entire simulation segment is used as the threshold. Step S33: Based on steps S23, S31, and S32, calculate the cumulative risk of each velocity node in the vibration damper characteristics using simulation data: Scan the simulation time domain, distinguish between the tension and compression sections of the shock absorber, and calculate the dimensionless excess ratio of the three risk factors at each simulation time according to the set threshold of each risk factor. A risk calculation function is set up, and based on the fusion weight, the risk value of the front and rear shock absorbers at the corresponding velocity node position at each simulation time in the tension and compression segments is calculated respectively. The risk values ​​corresponding to the same velocity node at all simulation times are superimposed to obtain the cumulative risk of each velocity node.

[0017] In one embodiment, the formula for calculating the threshold in step S32 is as follows: ,

[0018] in, For the first The pitch angle at a given moment in the simulation. For the first At each simulated moment, the pitch angular velocity... The equivalent front and rear axle speeds at all simulation times. Positive or zero data, The equivalent front and rear axle speeds at all simulation times. Negative data for mean for mean The average absolute value of the pitch angle at all simulation moments. The average absolute value of the pitch angular velocity at all simulation moments. For the equivalent vibration damper data The velocity values ​​at each simulation moment.

[0019] In one embodiment, cumulative risk The specific calculation formula is as follows: when , When the array length is equal to 2, that is Not empty:

[0020] when ， When the array length is equal to 1, that is... Empty, or Empty:

[0021] when ， When the array length is equal to 2, that is Not empty:

[0022] when ， When the array length is equal to 1, that is... Empty, or Empty:

[0023] in, and To put the front The cumulative front and rear axle equivalent damper velocities after mapping to the velocity node position in the damper characteristics. Step risk value, and To put the front The cumulative front and rear axle equivalent damper velocities after mapping to the velocity node position in the damper characteristics. Step risk value; when At that time, the cumulative risk value is the value at different speed nodes of the vibration damper under all simulation steps.

[0024] In one embodiment, step S4 includes: Step S41: Obtain the results from step S33 and Integrate into The maximum risk percentage is reconstructed according to each speed node to obtain the reconstructed cumulative risk array, where j is the total number of speed nodes of the shock absorber characteristic, t is the t-th speed node, and t = 1, 2, …, j; The specific formula for reconstructing the calculation is as follows:

[0025] Smooth the reconstructed data:

[0026] To prevent the maximum value from deviating from 1 after smoothing, the data is checked: for The location of the maximum value; This is the cumulative risk array after final verification; Step S42: Based on step S41, obtain the final cumulative risk array. The cumulative risk array is mapped to the damping force adjustment coefficient of the corresponding velocity node, and the reference amplification factor is set. Set the range of magnification fluctuation. The proportional control calculation is performed using a linear weighted adjustment method to obtain the optimized characteristics of the front and rear shock absorbers. The specific calculation method includes:

[0027] in, To set the lower limit of the amplification factor fluctuation range, To set the upper limit of the amplification factor fluctuation range, This is the equivalent damping force of the original front and rear axle shock absorbers. To optimize the damping force of the shock absorber.

[0028] The present invention has the following beneficial effects: The cumulative risk of each speed segment of the shock absorber is calculated based on a cost function that quantifies the advantages and disadvantages of the system. According to the set damping reference amplification factor and variation range, the different effects of damping force on passability and comfort at different speed segments of the shock absorber are considered. With the goal of balancing passability and comfort, the driving safety under extreme conditions is improved while reducing the impact on comfort. The damping force is adjusted in segments at different speed segments to optimize the damping force of the shock absorber, avoiding the need to increase the damping force by a fixed multiple across the entire speed range. The characteristics of the front and rear shock absorbers are obtained, reducing the increase of damping force in the low and medium speed range, reducing the impact on comfort, and increasing the damping in the high speed range, thereby enhancing the ultimate passability. The passability results are better than the passability results calculated by increasing the damping force by a fixed multiple across the entire speed range. Attached Figure Description

[0029] Figure 1 This is a flowchart illustrating a method for monitoring and adaptively adjusting the cumulative risk of a vibration damper according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the process for calculating the fused weight data of all simulation steps according to an embodiment of the present invention; Figure 3 This is a schematic diagram illustrating the process of calculating the cumulative risk value at different speed nodes of the vibration damper during all simulation steps, according to an embodiment of the present invention. Figure 4 This is a schematic diagram of the process for optimizing the damping force of the front and rear shock absorbers according to an embodiment of the present invention. Figure 5 This is a schematic diagram of the multiplier curve of the front / rear optimized damper damping force method according to an embodiment of the present invention; Figure 6a This is a schematic diagram showing the passability calculation results after increasing the damping force by 1.5 times under the original damper characteristics according to an embodiment of the present invention. Figure 6b This is a schematic diagram of the optimized vibration damper characteristics passability calculation results according to an embodiment of the present invention. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0031] Figure 1 This is a flowchart illustrating a method for monitoring and adaptively adjusting the cumulative risk of a vibration damper according to an embodiment of the present invention. The method includes the following steps: Step S1: Use multibody dynamics simulation software to build the models of each subsystem and the whole vehicle multibody model; process the actual road test road surface model, determine the road surface resolution and driving center line, determine the driving speed, perform simulation calculations consistent with the actual road test requirements, and obtain the result data; Step S2: Based on the result data, obtain the velocity data of four vibration dampers in the time domain, front and rear, and calculate the average velocity of the vibration dampers on the left and right sides of the front and rear axles point by point to obtain the equivalent velocity of the front and rear axles; match the equivalent velocity with multiple velocity nodes obtained by discretizing the original vibration damper characteristic data, and calculate the fusion weight mapped to the corresponding velocity node at each simulation time according to the distance and positional relationship between the equivalent velocity value and the velocity node; Step S3: Define risk factors, which include at least pitch angle, pitch rate, and equivalent speeds of the front and rear axes; set a threshold for each risk factor, and calculate the dimensionless overshoot ratio of each risk factor at each simulation time; calculate the risk value based on the fusion weight and the dimensionless overshoot ratio, and accumulate the risk values ​​corresponding to each speed node at all simulation times to obtain the cumulative risk. Step S4: Set the reference damping force amplification factor and variation range, determine the adjustment coefficient of each speed node based on the accumulated risk, and use proportional control to map the adjustment coefficient to the damping force of the speed node corresponding to the original shock absorber characteristics to obtain the optimized front and rear shock absorber characteristics.

[0032] In one embodiment, the result data includes at least the time-domain result data of the damper speed, pitch angle, and pitch angular velocity.

[0033] In one embodiment, such as Figure 2 As shown, step S2 specifically includes: Step S21: Based on the result data, obtain the speed data of four shock absorbers in the time domain of the result data, calculate the average speed of the shock absorbers on the left and right sides of the front and rear axles point by point, and obtain the equivalent speed of the front and rear axles. Step S22: Based on step S21, scan the equivalent velocity of the front and rear axle dampers at each step in the simulation time domain, compare it with all velocity nodes in the damper characteristic data, and obtain the velocity nodes and node positions that match the equivalent velocity. When the vibration damper characteristic data contains the equivalent velocity at the current simulation moment, in order to achieve accurate matching, the equivalent velocity value and its position in the characteristic data are used as the velocity node and node position. When the damper characteristic data does not contain the equivalent velocity of the current simulation step, for approximate matching, the maximum value of the characteristic data that is less than the equivalent velocity and the minimum value that is greater than the equivalent velocity are selected, and their equivalent velocity values ​​and positions are determined as velocity nodes and node positions respectively. Step S23: Based on the speed nodes and node positions matched in the characteristics of the front and rear dampers obtained in steps S21 and S22, calculate the fusion weight mapped to the corresponding node at each simulation moment. When it is an exact match, the fusion weight of the matching node is set to 1; When approximating the speed, if the equivalent speed exceeds the range of the original damper characteristic data, the fusion weight of the mapped limit speed node is set to 1. When the approximate match is achieved and the equivalent speed is located between the speed nodes of the original damper characteristic data, the distance weight is calculated based on the inverse ratio of the equivalent speed to the distance between these two speed nodes. Simultaneously, the position weight is calculated based on the cube of the speed value of the characteristic speed node to increase the weight of the high-speed segment. The distance weight and the position weight are weighted and fused to obtain the fused weights mapped to these two speed nodes respectively.

[0034] In one embodiment, in step S21, the equivalent speeds of the front and rear axles... The specific calculation formula is as follows:

[0035] in, For simulation time, This represents the total number of simulation steps. , , , These are the front left shock absorber, front right shock absorber, rear left shock absorber, and rear right shock absorber, respectively. The velocity value at each simulation moment For the front axle shock absorber in the first The equivalent velocity at any given moment. For the rear axle vibration damper in the first The equivalent velocity at any given moment.

[0036] In one embodiment, step S22, determining its velocity value and position as the velocity node and node position respectively, specifically includes: ,in , ; in, The original foundation vibration damper speed data, These correspond to the front and rear equivalent vibration damper data, respectively. for The first in One speed data point, For the equivalent vibration damper data The velocity values ​​at each simulation moment; To screen out Less than in the array The maximum value; for exist In the middle position, when Less than When all values ​​in the array are present, and Empty; To screen out array greater than The minimum value, for exist In the middle position, when Greater than When all values ​​in the array are present, and Empty; when , ; when , ; when , ; when and , , ; in For the first At each simulation moment, based on the equivalent damper data Obtained vibration damper characteristics The speed nodes and node positions matched in the middle.

[0037] In one embodiment, step S23, the formula for calculating the fusion weight specifically includes:

[0038] when When the array length is equal to 2, that is None of them are empty;

[0039] The specific calculation of the fusion weight for the first velocity node is as follows:

[0040] The specific calculation of the fusion weight for the second velocity node is as follows: ; when When the array length is equal to 1, that is... Empty, or Empty; The specific calculation of the fusion weight for the corresponding velocity node is as follows: .

[0041] In one embodiment, such as Figure 3 As shown, step S3 specifically includes: Step S31: Define risk factors, which include pitch angle, pitch angular velocity, and equivalent velocity values ​​of the front and rear axles of the shock absorber obtained in step S21. Step S32: Define the threshold for each risk factor based on step S31: For the equivalent velocity values ​​of the front and rear shafts of the shock absorber, the tension section and compression section of the shock absorber are distinguished according to the positive and negative values ​​of the equivalent velocity values, and the average value of all tension section velocity values ​​and the average value of all compression section velocity values ​​in the simulation are used as thresholds respectively. For the pitch angle and pitch velocity, the mean of the absolute values ​​of all data within the entire simulation segment is used as the threshold. Step S33: Based on steps S23, S31, and S32, calculate the cumulative risk of each velocity node in the vibration damper characteristics using simulation data: Scan the simulation time domain, distinguish between the tension and compression sections of the shock absorber, and calculate the dimensionless excess ratio of the three risk factors at each simulation time according to the set threshold of each risk factor. A risk calculation function is set up, and based on the fusion weight, the risk value of the front and rear shock absorbers at the corresponding velocity node position at each simulation time in the tension and compression segments is calculated respectively. The risk values ​​corresponding to the same velocity node at all simulation times are superimposed to obtain the cumulative risk of each velocity node.

[0042] In one embodiment, the formula for calculating the threshold in step S32 is as follows: ,

[0043] in, For the first The pitch angle at a given moment in the simulation. For the first At each simulated moment, the pitch angular velocity... The equivalent front and rear axle speeds at all simulation times. Positive or zero data, The equivalent front and rear axle speeds at all simulation times. Negative data for mean for mean The average absolute value of the pitch angle at all simulation moments. The average absolute value of the pitch angular velocity at all simulation moments. For the equivalent vibration damper data The velocity values ​​at each simulation moment.

[0044] Specifically, when Calculate the time at each simulation moment , , The dimensionless excess rates of these three risk factors. When Calculate the time at each simulation moment , , The dimensionless excess rates of these three risk factors.

[0045] In one embodiment, cumulative risk The specific calculation formula is as follows: when , When the array length is equal to 2, that is Not empty:

[0046] when ， When the array length is equal to 1, that is... Empty, or Empty:

[0047] when ， When the array length is equal to 2, that is Not empty:

[0048] when ， When the array length is equal to 1, that is... Empty, or Empty:

[0049] in, and To put the front The cumulative front and rear axle equivalent damper velocities after mapping to the velocity node position in the damper characteristics. Step risk value, and To put the front The cumulative front and rear axle equivalent damper velocities after mapping to the velocity node position in the damper characteristics. Step risk value; when At that time, the cumulative risk value is the value at different speed nodes of the vibration damper under all simulation steps.

[0050] In one embodiment, such as Figure 4 As shown, step S4 includes: Step S41: Obtain the results from step S33 and Integrate into The maximum risk percentage is reconstructed according to each speed node to obtain the reconstructed cumulative risk array, where j is the total number of speed nodes of the shock absorber characteristic, t is the t-th speed node, and t = 1, 2, …, j; The specific formula for reconstructing the calculation is as follows:

[0051] Smooth the reconstructed data:

[0052] To prevent the maximum value from deviating from 1 after smoothing, the data is checked: for The location of the maximum value; This is the cumulative risk array after final verification; Step S42: Based on step S41, obtain the final cumulative risk array. The cumulative risk array is mapped to the damping force adjustment coefficient of the corresponding velocity node, and the reference amplification factor is set. Set the range of magnification fluctuation. The proportional control calculation is performed using a linear weighted adjustment method to obtain the optimized characteristics of the front and rear shock absorbers. The specific calculation method includes:

[0053] in, To set the lower limit of the amplification factor fluctuation range, To set the upper limit of the amplification factor fluctuation range, This is the equivalent damping force of the original front and rear axle shock absorbers. To optimize the damping force of the shock absorber.

[0054] Figure 5 This figure shows the damping force amplification curves of the front and rear shock absorbers optimized according to the method of this invention. The horizontal axis represents the velocity nodes in the original shock absorber characteristic data, and the vertical axis represents the damping amplification factor calculated by the algorithm. The dashed line in the figure represents the set reference amplification factor, the gray shaded area represents the fluctuation range of the optimizable amplification factor automatically set by the algorithm, and the circles represent the actual amplification factor calculated by the algorithm at each velocity node. This amplification factor directly acts on the original damping force at the corresponding velocity node to obtain the optimized shock absorber characteristics.

[0055] like Figure 5 As shown, in the low-speed range of the shock absorber, the amplification factor calculated by the algorithm is less than the set reference amplification factor; in the high-speed range, the amplification factor is greater than the reference amplification factor. This result demonstrates that the method of the present invention, by introducing a position weight equal to the cube of the velocity in the fusion weight in step S2 to increase the basic weight in the high-speed range, and by distinguishing between the tension and compression sections and performing proportional control based on cumulative risk in step S3, enables the optimized shock absorber characteristics to provide greater damping force in the high-speed range to improve passability and avoid bottoming out, while reducing damping force in the low-speed range to minimize the impact on comfort. This verifies that the method of the present invention can effectively balance vehicle passability and comfort.

[0056] Furthermore, Figure 6a The results of the passability calculation are based on the original shock absorber characteristics and the damping force at full speed range increased by 1.5 times. It can be seen that the gap between the subframe and the road surface is extremely small, and there is still a risk of collision. Figure 6b The results of the optimized shock absorber characteristics passability calculation using the method of this invention show that the gap between the subframe and the road surface is significantly increased, effectively reducing the risk of collision.

[0057] Combination Figure 5As shown in the damping amplification curve calculated by the method of the present invention, the method automatically reduces the damping force amplification factor (less than the reference value of 1.15) in the low-to-medium speed range, reducing the impact on overall vehicle comfort. Simultaneously, it automatically increases the damping force amplification factor (greater than the reference value of 1.15) in the high-speed range. The increase in damping force in the high-speed range contributes far more to passability and preventing bottoming out than to comfort. The passability comparison results verify that the method of the present invention can effectively improve vehicle passability while maintaining comfort.

[0058] In the description of this application, it should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. For ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0059] It should be noted that, in this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. It should also be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Furthermore, features described with reference to certain examples may be combined in other examples.

[0060] The embodiments described above are merely further illustrations of the present invention and are not intended to limit the present invention in any other way. The present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding modifications and changes based on the present invention, but all such modifications and changes should fall within the protection scope of the present invention.

Claims

1. A method for monitoring and adaptively adjusting the cumulative risk of a vibration damper, characterized in that, The method includes the following steps: Step S1: Use multibody dynamics simulation software to build the models of each subsystem and the whole vehicle multibody model; process the actual road test road surface model, determine the road surface resolution and driving center line, determine the driving speed, perform simulation calculations consistent with the actual road test requirements, and obtain the result data; Step S2: Based on the result data, obtain the speed data of four vibration dampers in the time domain, front and rear, and calculate the average speed of the vibration dampers on the left and right sides of the front and rear axles point by point to obtain the equivalent speed of the front and rear axles; match the equivalent speed with multiple characteristic speed nodes obtained by discretizing the original vibration damper characteristic data, and calculate the fusion weight mapped to the corresponding speed node at each simulation time according to the distance and position relationship between the equivalent speed value and the speed node; Step S3: Define risk factors, which include at least pitch angle, pitch rate, and equivalent speeds of the front and rear axes; set a threshold for each risk factor, and calculate the dimensionless overshoot ratio of each risk factor at each simulation time; calculate the risk value based on the fusion weight and the dimensionless overshoot ratio, and accumulate the risk values ​​corresponding to each speed node at all simulation times to obtain the cumulative risk. Step S4: Set the reference damping force amplification factor and variation range, determine the adjustment coefficient of each speed node based on the accumulated risk, and use proportional control to map the adjustment coefficient to the damping force of the speed node corresponding to the original shock absorber characteristics to obtain the optimized front and rear shock absorber characteristics.

2. The method for monitoring and adaptively adjusting the cumulative risk of a vibration damper according to claim 1, characterized in that, The results data include at least the time-domain results data of the damper speed, pitch angle, and pitch angular velocity.

3. The method for monitoring and adaptively adjusting the cumulative risk of a vibration damper according to claim 2, characterized in that, Step S2 specifically includes: Step S21: Based on the result data, obtain the speed data of four shock absorbers in the time domain of the result data, calculate the average speed of the shock absorbers on the left and right sides of the front and rear axles point by point, and obtain the equivalent speed of the front and rear axles. Step S22: Based on step S21, scan the equivalent velocity of the front and rear axle dampers at each step in the simulation time domain, compare it with all velocity nodes in the damper characteristic data, and obtain the velocity nodes and node positions that match the equivalent velocity. When the vibration damper characteristic data contains the equivalent velocity at the current simulation moment, in order to achieve accurate matching, the equivalent velocity value and its position in the characteristic data are used as the velocity node and node position. When the damper characteristic data does not contain the equivalent velocity of the current simulation step, for approximate matching, the maximum value of the characteristic data that is less than the equivalent velocity and the minimum value that is greater than the equivalent velocity are selected, and their equivalent velocity values ​​and positions are determined as velocity nodes and node positions respectively. Step S23: Based on the speed nodes and node positions matched in the characteristics of the front and rear dampers obtained in steps S21 and S22, calculate the fusion weight mapped to the corresponding node at each simulation moment. When it is an exact match, the fusion weight of the matching node is set to 1; When approximating the speed, if the equivalent speed exceeds the range of the original damper characteristic data, the fusion weight of the mapped limit speed node is set to 1. When the approximate match is achieved and the equivalent speed is located between the speed nodes of the original damper characteristic data, the distance weight is calculated based on the inverse ratio of the equivalent speed to the distance between these two speed nodes. Simultaneously, the position weight is calculated based on the cube of the speed value of the characteristic speed node to increase the weight of the high-speed segment. The distance weight and the position weight are weighted and fused to obtain the fused weights mapped to these two speed nodes respectively.

4. The method for monitoring and adaptively adjusting the cumulative risk of a vibration damper according to claim 3, characterized in that, In step S21, the equivalent speeds of the front and rear axles The specific calculation formula is as follows: in, For simulation time, This represents the total number of simulation steps. , , , These are the front left shock absorber, front right shock absorber, rear left shock absorber, and rear right shock absorber, respectively. The velocity value at that moment. For the front axle shock absorber in the first The equivalent velocity at any given moment. For the rear axle vibration damper in the first The equivalent velocity at any given moment.

5. The method for monitoring and adaptively adjusting the cumulative risk of a vibration damper according to claim 4, characterized in that, In step S22, determining the velocity node and its position specifically includes: ,in , ； in, The original vibration damper speed data, These correspond to the front and rear equivalent vibration damper data, respectively. for The first in One speed data point, For the equivalent vibration damper data The velocity value at each moment; To screen out Less than in the array The maximum value; for exist In the middle position, when Less than When all values ​​in the array are present, and Empty; To screen out array greater than The minimum value, for exist In the middle position, when Greater than When all values ​​in the array are present, and Empty; when , ; when , ; when , ; when and , ， ； in For the first At that moment, according to the equivalent damper data Obtained vibration damper characteristics The speed nodes and node positions matched in the middle.

6. The method for monitoring and adaptively adjusting the cumulative risk of a vibration damper according to claim 5, characterized in that, In step S23, the fusion weight calculation method specifically includes: when When the array length is equal to 2, that is None of them are empty; The specific calculation of the fusion weight for the first velocity node is as follows: The specific calculation of the fusion weight for the second velocity node is as follows: ； when When the array length is equal to 1, that is... Empty, or Empty; The specific calculation of the fusion weight for the corresponding velocity node is as follows: 。 7. The method for monitoring and adaptively adjusting the cumulative risk of a vibration damper according to claim 6, characterized in that, Step S3 specifically includes: Step S31: Define risk factors, which include pitch angle, pitch angular velocity, and equivalent velocity values ​​of the front and rear axles of the shock absorber obtained in step S21. Step S32: Define the threshold for each risk factor based on step S31: For the equivalent velocity values ​​of the front and rear shafts of the shock absorber, the tension section and compression section of the shock absorber are distinguished according to the positive and negative values ​​of the equivalent velocity values, and the average value of all tension section velocity values ​​and the average value of all compression section velocity values ​​in the simulation are used as thresholds respectively. For the pitch angle and pitch velocity, the mean of the absolute values ​​of all data within the entire simulation segment is used as the threshold. Step S33: Based on steps S23, S31, and S32, calculate the cumulative risk of each velocity node in the vibration damper characteristics using simulation data: Scan the simulation time domain, distinguish between the tension and compression sections of the shock absorber, and calculate the dimensionless excess ratio of the three risk factors at each simulation time according to the set threshold of each risk factor. A risk calculation function is set up, and based on the fusion weight, the risk value of the front and rear shock absorbers at the corresponding velocity node position at each simulation time in the tension and compression segments is calculated respectively. The risk values ​​corresponding to the same velocity node at all simulation times are superimposed to obtain the cumulative risk of each velocity node.

8. The method for monitoring and adaptively adjusting the cumulative risk of a vibration damper according to claim 7, characterized in that, In step S32, the specific formula for calculating the threshold is as follows: ， in, For the first The pitch angle at a given moment in the simulation. For the first At each simulated moment, the pitch angular velocity... The equivalent front and rear axle speeds at all simulation times. Positive or zero data, The equivalent front and rear axle speeds at all simulation times. Negative data for mean for mean The average absolute value of the pitch angle at all simulation moments. The average absolute value of the pitch angular velocity at all simulation moments. For the equivalent vibration damper data The velocity values ​​at each simulation moment.

9. The method for monitoring and adaptively adjusting the cumulative risk of a vibration damper according to claim 8, characterized in that, Cumulative risk The specific calculation formula is as follows: when , When the array length is equal to 2, that is Not empty: when ， When the array length is equal to 1, that is... Empty, or Empty: when ， When the array length is equal to 2, that is Not empty: when ， When the array length is equal to 1, that is... Empty, or Empty: in, and To put the front The cumulative front and rear axle equivalent damper velocities after mapping to the velocity node position in the damper characteristics. Step risk value, and To put the front The cumulative front and rear axle equivalent damper velocities after mapping to the velocity node position in the damper characteristics. Step risk value; when At that time, the cumulative risk value is the value at different speed nodes of the vibration damper under all simulation steps.

10. The method for monitoring and adaptively adjusting the cumulative risk of a vibration damper according to claim 9, characterized in that, Step S4 includes: Step S41: Obtain the results from step S33 and Integrate into The maximum risk percentage is reconstructed according to each speed node to obtain the reconstructed cumulative risk array, where j is the total number of speed nodes of the shock absorber characteristic, t is the t-th speed node, and t = 1, 2, …, j; The specific formula for reconstructing the calculation is as follows: Smooth the reconstructed data: To prevent the maximum value from deviating from 1 after smoothing, the data is checked: for The location of the maximum value; This is the cumulative risk array after final verification; Step S42: Based on step S41, obtain the final cumulative risk array. The cumulative risk array is mapped to the damping force adjustment coefficient of the corresponding velocity node, and the reference amplification factor is set. Set the range of magnification fluctuation. The proportional control calculation is performed using a linear weighted adjustment method to obtain the optimized characteristics of the front and rear shock absorbers. The specific calculation method includes: in, To set the lower limit of the amplification factor fluctuation range, To set the upper limit of the amplification factor fluctuation range, This is the equivalent damping force of the original front and rear axle shock absorbers. To optimize the damping force of the shock absorber.

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