WO2025194733A1 - Control method and control system for suspension system of vehicle, and vehicle - Google Patents

Abstract

Embodiments of the present disclosure provide a control method and a control system for a suspension system of a vehicle, and a vehicle. The method comprises: on the basis of road surface information ahead of a vehicle during traveling and a working condition parameter of the vehicle, performing first adjustment on a damping parameter of at least one shaft among a plurality of shafts of a suspension system; on the basis of the road surface information and the working condition parameter, performing second adjustment on a rigidity parameter of at least one shaft among the plurality of shafts of the suspension system; and, on the basis of road surface excitation information and an operating state parameter of the vehicle and a weight matrix corresponding to the working condition parameter, performing third adjustment on a control force parameter of at least one shaft among the plurality of shafts of the suspension system.

Description

Control method and control system of vehicle suspension system, and vehicle

This application claims priority to Chinese patent application No. 202410325421.5 filed on March 20, 2024, the entire contents of which are incorporated herein by reference.

Technical Field

The present disclosure relates to the field of suspension control, and in particular to a control method and control system of a vehicle suspension system, and a vehicle.

Background Art

Vehicle ride comfort refers to the ability to reduce vibration and impact while traveling within a preset speed range, or to prevent damage to cargo. Vehicle ride comfort is one of the key performance characteristics of high-speed vehicles.

Summary of the Invention

The purpose of the present disclosure is to provide a control method, a control system, and a vehicle for a vehicle suspension system. The control method can be applied to a suspension dynamics matching scheme for a multi-axle vehicle, so that the active suspension can ensure rapid system response while providing the vehicle with better smoothness and handling stability as well as a more comprehensive smoothness optimization effect, thereby broadening the applicability of the active suspension and increasing the service life of the vehicle.

To achieve the above objectives, an embodiment of the present disclosure provides a method for controlling a suspension system of a vehicle, the method comprising at least one of the following: first adjusting the damping parameters of at least one of the multiple axes of the suspension system based on road surface information ahead of the vehicle and operating parameters of the vehicle; or second adjusting the stiffness parameters of at least one of the multiple axes of the suspension system based on the road surface information and the operating parameters. The method also comprises thirdly adjusting the control force parameters of at least one of the multiple axes of the suspension system based on road surface excitation information of the vehicle, operating state parameters, and a weight matrix corresponding to the operating parameters.

In some embodiments, the road surface information includes pulse road surface and random road surface, and the operating condition parameters include the wading depth, tire pressure and wheel angle of the vehicle. The first adjustment of the damping parameters of at least one of the multiple axes of the suspension system includes one of the following: when the wading depth is greater than a depth threshold, or when the road surface information is the random road surface and the tire pressure is greater than a tire pressure threshold or the wheel angle is greater than an angle threshold, adjusting the damping parameters of the multiple axes to equal damping for each of the multiple axes; when the wading depth is less than or equal to the depth threshold, the road surface information is the pulse road surface and the tire pressure is greater than the tire pressure threshold or the wheel angle is greater than the angle threshold, or when the wading depth is less than or equal to the depth threshold, When the wading depth is less than or equal to the depth threshold, the road surface information is the random road surface, the tire pressure is less than or equal to the tire pressure threshold, and the wheel angle is less than or equal to the angle threshold, the damping parameters of the multiple shafts are adjusted so that the damping ratio of each shaft is equal, and the damping ratio of each shaft is related to the damping, stiffness and sprung mass of the shaft; and when the wading depth is less than or equal to the depth threshold, the road surface information is the pulse road surface, the tire pressure is less than or equal to the tire pressure threshold, and the wheel angle is less than or equal to the angle threshold, the damping parameters of the multiple shafts are adjusted so that the damping of the middle shaft of the multiple shafts is the maximum.

In some embodiments, when the suspension system includes three axles, the damping ratio of each axle is expressed as follows:

_ζ1 is the damping ratio of the front axle among the three axles, _ζ2 is the damping ratio of the intermediate axle among the three axles, _{and ζ3} is the damping ratio of the rear axle among the three axles; _m1 is the sprung mass of the front axle, _m2 is the sprung mass of the intermediate axle, and _m3 is the sprung mass of the rear axle. _{C m1} is the output parameter of the front axle shock absorber, _Fm1 is the average of the return and compression resistances of the front axle shock absorber. _vm1 is the speed corresponding to the moment _Fm1 , and _D1 is the design parameter of the front axle shock absorber. _Cm2 is the output parameter of the intermediate axle shock absorber, _Fm2 is the average of the return and compression resistances of the intermediate axle shock absorber. _vm2 is the speed corresponding to the moment _Fm2 , and _D2 is the design parameter of the intermediate axle shock absorber. _Cm3 is the output parameter of the rear axle shock absorber, _Fm3 is the average of the return and compression resistances of the rear axle shock absorber. _vm3 is the speed corresponding to the moment _Fm3 , _{and D3} is the design parameter of the rear axle shock absorber. _k1 and _k2 are the stiffnesses of the two wheels corresponding to the front axle, _k3 and _k4 are the stiffnesses of the two wheels corresponding to the intermediate axle, and _k5 and _k6 are the stiffnesses of the two wheels corresponding to the rear axle.

In some embodiments, the control method further includes: when the driving speed of the vehicle is less than or equal to a speed threshold, the second adjustment is performed simultaneously with the first adjustment. The stiffness parameters include stiffness and offset frequency. The second adjustment of the stiffness parameters of at least one of the multiple shafts of the suspension system includes one of the following: when the wading depth is greater than the depth threshold, or when the road surface information is the random road surface, or when the road surface information is the pulse road surface, the tire pressure is less than or equal to the tire pressure threshold, and the wheel angle is less than or equal to the angle threshold, adjusting the stiffness parameters of the multiple shafts to the maximum stiffness of the middle shaft of the multiple shafts.

In some embodiments, the control method further includes: when the driving speed of the vehicle is greater than a speed threshold, the second adjustment is performed after the first adjustment. The first adjustment also includes multiple adjustments to the damping parameters. The second adjustment of the stiffness parameters of at least one of the multiple axes of the suspension system includes one of the following: when the road surface information and the operating condition parameters of the vehicle corresponding to each adjustment in the multiple adjustments meet the first setting conditions, the stiffness parameters of the multiple axes are adjusted to the maximum stiffness of the middle axis of the multiple axes, and the first setting conditions are: the road surface information is the random road surface, the wading depth is less than or equal to the depth threshold, and the tire pressure is greater than the tire pressure threshold or the wheel angle is greater than the angle threshold; when the road surface information and the operating condition parameters of the vehicle corresponding to each adjustment in the multiple adjustments meet the second setting conditions. Under certain conditions, the stiffness parameters of the multiple axes are adjusted to the frequency deviation of each axis of the multiple axes being equal, and the second setting condition is: the road surface information is the pulse road surface, the wading depth is greater than the depth threshold, or the tire pressure is less than or equal to the tire pressure threshold and the wheel angle is less than or equal to the angle threshold; and, when the road surface information and the operating condition parameters of the vehicle corresponding to any one of the multiple adjustments meet the first setting condition and the road surface information and the operating condition parameters of the vehicle corresponding to another one of the multiple adjustments meet the second setting condition, the stiffness parameters of the multiple axes are not adjusted.

In some embodiments, when the suspension system includes three axes, the offset frequency of each of the three axes is equal to the following formula:

k ₁ ＝k ₂ k ₃ ＝k ₄ k ₅ ＝k ₆ ,

_m1 is the sprung mass of the front axle among the three axles, _m2 is the sprung mass of the middle axle among the three axles, _{and m3} is the sprung mass of the rear axle among the three axles; _k1 and _k2 are the stiffnesses of the two wheels corresponding to the front axle, _k3 and _k4 are the stiffnesses of the two wheels corresponding to the middle axle, and _k5 and _k6 are the stiffnesses of the two wheels corresponding to the rear axle.

In some embodiments, the control method further includes: identifying the road surface information as the road surface information by a camera installed on the vehicle. The pulse road surface or the random road surface. The acquisition angle of the camera is fixed or variable. In the case where the acquisition angle is variable, the acquisition angle is related to the driving speed of the vehicle.

In some embodiments, the third adjustment of the control force parameters of at least one of the multiple axes of the suspension system includes: determining a first relationship between an output matrix of the suspension system and an active control force matrix of the suspension system based on a road surface excitation matrix corresponding to the road surface excitation information and an operating state matrix corresponding to the operating state parameters, the output matrix including the vehicle's body acceleration, pitch angular acceleration, suspension travel, and wheel vertical displacement, and the operating state matrix including the vehicle's center of mass vertical displacement, vertical velocity, pitch angle, pitch angular velocity, wheel vertical displacement, and wheel vertical velocity values; determining a second relationship between a comprehensive score of the suspension system and the active control force matrix based on the first relationship, an evaluation parameter score corresponding to the output matrix, and a weight matrix corresponding to the vehicle's operating condition parameters; determining, based on the second relationship, an active control force matrix that maximizes the comprehensive score as a target control force matrix of the suspension system; and adjusting the control force parameters of at least one of the multiple axes of the suspension system based on the target control force matrix.

In some embodiments, the first relationship and the second relationship satisfy one of the following:

The first relationship is expressed as follows:
Y＝PX+QZ _r +RU，

Y is the output matrix of the suspension system, U is the active control force matrix of the suspension system, X is the operating state matrix, _Zr is the road excitation matrix, P is the first coefficient matrix of the operating state matrix X, Q is the second coefficient matrix of the road excitation matrix _Zr , and R is the third coefficient matrix of the active control force matrix U.

or

The second relationship is expressed as follows:

_Nw is the comprehensive score of the suspension system, _Ni is the evaluation parameter score corresponding to the output matrix Y, and Sj _,i is the weight matrix corresponding to the vehicle's operating parameters. In the case where the suspension system includes three axles, j = 1, 2, 3, and n = 14.

On the other hand, the present disclosure provides a control system for a suspension system of a vehicle. The control system includes: at least one of a first adjustment device or a second adjustment device, and a third adjustment device. The first adjustment device is configured to perform a first adjustment on the damping parameters of at least one of the multiple axes of the suspension system based on the road surface information in front of the vehicle and the operating parameters of the vehicle. The second adjustment device is configured to perform a second adjustment on the stiffness parameters of at least one of the multiple axes of the suspension system based on the road surface information and the operating parameters. The third adjustment device is configured to perform a third adjustment on the control force parameters of at least one of the multiple axes of the suspension system based on the road surface excitation information of the vehicle, the operating state parameters and the weight matrix corresponding to the operating parameters.

In yet another aspect, the present disclosure provides an electronic device comprising: at least one processor and a memory. The memory is connected to the at least one processor. The memory stores instructions executable by the at least one processor, and the at least one processor implements the above-described method for controlling a vehicle suspension system by executing the instructions stored in the memory.

In yet another aspect, the present disclosure provides a machine-readable storage medium having instructions stored thereon. When executed by a processor, the instructions cause the processor to be configured to execute the control method for a vehicle suspension system as described above.

In yet another aspect, the present disclosure provides a vehicle comprising the control system of the suspension system described above.

Through the above technical solution, the present disclosure provides a control method, control system, and vehicle for a vehicle suspension system. This control method can be applied to the active suspension system of a multi-axle vehicle, ensuring that the multi-axle vehicle achieves the optimal ride comfort matching solution before active control, resolving the hysteresis problem of active suspension control, improving vehicle comfort, maintaining ride comfort under special operating conditions, broadening the applicability of active suspension, and increasing vehicle service life. Specific beneficial effects include:

The present disclosure provides three optimization methods for ride comfort: stiffness, damping, and force control. Damping adjustment has the effect of rapid response, reducing roll and shake during sharp turns and high speeds, reducing wear on the suspension and body, and extending the service life of the vehicle. Stiffness adjustment has the effect of addressing the tire contact area and simultaneously affecting the ride comfort and handling stability of the vehicle. Force control adjustment has the effect of optimizing various ride comfort evaluation parameters simultaneously or focusing on a specific evaluation parameter. Therefore, compared with related technologies, the present disclosure has all three adjustment methods, allowing the active suspension to ensure rapid system response while providing the vehicle with better ride comfort and handling stability, as well as a more comprehensive ride comfort optimization effect.

In addition, the control method disclosed in the present invention first pre-adjusts the stiffness parameters and damping parameters of the vehicle's suspension system, and then performs secondary adjustment on the control force parameters of the vehicle's suspension system. This adjustment method can achieve a smoother state more quickly and improve the comfort of the vehicle more quickly.

Other features and advantages of the embodiments of the present disclosure will be described in detail in the subsequent detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are used to provide a further understanding of the embodiments of the present disclosure and constitute a part of the specification. Together with the following detailed description, they are used to explain the embodiments of the present disclosure but do not constitute a limitation of the embodiments of the present disclosure. In the accompanying drawings:

FIG1 is a schematic diagram of the basic structure of an active suspension system for a multi-axle vehicle according to some embodiments of the present disclosure;

FIG2 is a flow chart of a method for controlling a suspension system according to some embodiments of the present disclosure;

FIG3 is a schematic diagram of a road condition collection solution according to some embodiments of the present disclosure;

FIG4 is a schematic diagram of another road condition collection solution according to some embodiments of the present disclosure;

FIG5 is a schematic diagram of a 9-DOF vehicle dynamics model according to some embodiments of the present disclosure;

FIG6 is a flow chart of a control method of a suspension system under different working conditions according to some embodiments of the present disclosure;

FIG7 is a schematic diagram of a control system of a suspension system according to some embodiments of the present disclosure.

DETAILED DESCRIPTION

The following describes the specific implementation of the embodiment of the present disclosure in detail with reference to the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the embodiment of the present disclosure, and is not used to limit the embodiment of the present disclosure.

In order to ensure that vehicles, especially multi-axle vehicles, achieve the optimal smoothness matching solution before active control, and maintain the smoothness of multi-axle vehicles under special working conditions, a lot of exploration has been done in related technologies.

During the development of this disclosure, the inventors discovered that the related art active suspension control methods, which rely solely on active suspension and damping adjustments, are not fully applicable to multi-axle vehicles, cannot meet higher ride comfort requirements, and cannot accommodate a variety of operating conditions. Therefore, a suspension control method is urgently needed to address these issues.

To this end, some embodiments of the present disclosure first provide a method for controlling a vehicle suspension system. This control method can be applied to a vehicle's active suspension system, such as an active suspension system for a multi-axle vehicle (e.g., a three-axle bus). The basic structural schematic diagram of the active suspension system is shown in Figure 1. The active suspension system primarily includes an information acquisition module 1, a dynamics calculation module 2, a control module 3, and a suspension structure 4.

The information acquisition module 1 is configured to obtain vehicle information. The dynamic calculation module 2 is configured to output the corresponding control force (for example, the control force when the weight of the smoothness evaluation index is the smallest) based on the vehicle information. The control module 3 is configured to adjust the weight of the smoothness index and the suspension structure 4 based on the road conditions ahead of the vehicle. The suspension structure 4 has adjustable stiffness, damping, and output force. The adjustable stiffness, damping, and output force are achieved by adjusting the variable stiffness air spring 45, the magnetorheological damper 46, and the force controller 44, respectively, thereby adjusting the smoothness of the vehicle under different conditions by controlling the corresponding components.

In some embodiments, as shown in FIG2 , the control method may include: at least one of step S110 or step S120, and step S130. At least one of step S110 or step S120 is to pre-adjust the suspension system of the vehicle, and step S130 is to perform secondary adjustment on the suspension system of the vehicle.

Step S110 , performing a first adjustment on the damping parameters of at least one of the multiple axes of the suspension system according to road surface information ahead of the vehicle and operating parameters of the vehicle.

Damping parameters include the damping and damping ratio for each axle. Road surface information can include both pulsed and random road surfaces. These two conditions are common in vehicle testing. Random roads are typically smooth, as seen in everyday driving situations. Pulsed roads, on the other hand, are characterized by small obstacles (such as speed bumps, washboard roads, and potholes) and are relatively less smooth.

In some embodiments of the present disclosure, the camera 11 in the information acquisition module 1 can be used to identify road surface information as either a pulsed or random road surface. For example, this identification method can include using the camera 11 mounted on the vehicle to identify the height of obstacles ahead of the vehicle and, when the height exceeds a set height threshold, determining the road surface as a pulsed road surface. Alternatively, road surface type identification can be performed using image recognition, machine vision, or other methods.

In some embodiments, the operating parameters may include the vehicle's wading depth H, tire pressure P, and wheel angle The water level information can be obtained by the water level sensor 13 in the information acquisition module 1, thereby obtaining the wading depth H of the vehicle. The vehicle speed v, steering wheel angle, etc. can be called from the vehicle electronic control unit (ECU). Information acquisition module 1 then transmits the acquired road surface, vehicle, and water level information to dynamics calculation module 2 and control module 3. Control module 3 makes a judgment based on the road surface, vehicle, and water level information and outputs the judgment result to suspension structure 4, which controls variable-stiffness air spring 45 and magnetorheological damper 46 for pre-adjustment.

The magnetorheological damper 46 utilizes electromagnetic reactions, based on input from sensors monitoring vehicle body and wheel motion, to respond in real time to road conditions and the driving environment. This indicates that, through the combination of the information acquisition module 1 and the control module 3, some embodiments of the present disclosure are applicable not only to common road surfaces but also to regulating vehicle ride comfort under special water-crossing conditions. Compared to related technologies, some embodiments of the present disclosure can ensure vehicle ride comfort under a wider range of road conditions, enabling the vehicle to provide constant passenger comfort without being affected by road conditions.

In some embodiments, performing a first adjustment on the damping parameter of at least one axis among the plurality of axes of the suspension system may include step S111 , step S112 , or step S113 .

Step S111: When the wading depth H is greater than the depth threshold, or when the road surface information is a random road surface and the tire pressure P is greater than the tire pressure threshold or the wheel angle When the angle is greater than the threshold, the damping parameters of the multiple axes are adjusted so that the damping of each axis is equal.

In some embodiments, when the suspension system includes three axles, the damping C ₁ -C ₆ of the three axles are adjusted to be equal.

Step S112: When the wading depth H is less than or equal to the depth threshold, the road surface information is a pulse road surface, and the tire pressure P is greater than the tire pressure threshold or the wheel angle When the wading depth H is less than or equal to the depth threshold and the road surface information is random road surface, tire pressure P is less than or equal to the tire pressure threshold, and the wheel angle When the rotation angle is less than or equal to the angle threshold, the damping parameters of multiple axes are adjusted to make the damping ratio of each axis equal.

The damping ratio for each axle is related to the damping, stiffness, and sprung mass of that axle.

In some embodiments, when the suspension system includes three axles, the damping ratio of each axle is expressed as follows:

Among them, _ζ1 is the damping ratio of the front axle among the three axles, _ζ2 is the damping ratio of the middle axle among the three axles, _{and ζ3} is the damping ratio of the rear axle among the three axles; _m1 is the sprung mass of the front axle (also known as the equivalent sprung mass), _m2 is the sprung mass of the middle axle, and _m3 is the sprung mass of the rear axle.

C _m1 is the output parameter of the front axle shock absorber. _{F m1} is the average of the restoring resistance and compression resistance of the front axle shock absorber. v _m1 is the velocity corresponding to the moment F _m1 . D ₁ is the design parameter of the front axle shock absorber, which is related to the lever ratio of the front axle shock absorber and the angle between the centerline of the front axle shock absorber and the vertical line. Here, the shock absorber can include at least one of a variable-stiffness air spring 45 or a magnetorheological damper 46.

C _m2 is the output parameter of the intermediate shaft shock absorber. _{F m2} is the average of the restoring and compression resistances of the intermediate shaft shock absorber. v _m2 is the velocity corresponding to the moment F _m2 . D ₂ is the design parameter of the intermediate shaft shock absorber, which is related to the leverage ratio of the intermediate shaft shock absorber and the angle between the centerline of the intermediate shaft shock absorber and the plumb line.

C _m3 is the output parameter of the rear axle shock absorber. _{F m3} is the average of the restoring resistance and compression resistance of the rear axle shock absorber. v _m3 is the speed corresponding to the moment F _m3 . D ₃ is the design parameter of the rear axle shock absorber, which is related to the lever ratio of the rear axle shock absorber and the angle between the centerline of the rear axle shock absorber and the plumb line.

_k1 - _k6 are the variable stiffnesses of the variable stiffness air springs 45 corresponding to the six wheels 47 in the suspension structure 4. _k1 and _k2 are the stiffnesses of the two wheels corresponding to the front axle, _k3 and _k4 are the stiffnesses of the two wheels corresponding to the middle axle, and _k5 and _k6 are the stiffnesses of the two wheels corresponding to the rear axle.

Step S113: When the wading depth H is less than or equal to the depth threshold, the road surface information is a pulse road surface, the tire pressure P is less than or equal to the tire pressure threshold, and the wheel angle When the rotation angle is less than or equal to the rotation angle threshold, the damping parameters of the multiple axes are adjusted so that the damping of the middle axis of the multiple axes is the largest.

In some embodiments, when the suspension system includes three shafts, the damping C ₃ , C ₄ of the intermediate shafts are adjusted to be maximum.

In addition, the acquisition angle of the camera 11 can be set to be fixed or variable.

In some embodiments, as shown in Figure 3 , if the camera 11's acquisition angle is fixed, the camera 11 can be mounted on the vehicle's underbody. This arrangement expands the measurable range of the camera 11 and improves the overall responsiveness of the active suspension system. However, this also reduces the adjustability of the camera's acquisition angle, reducing its applicable range.

In some embodiments, as shown in FIG4 , where the camera 11 has a variable acquisition angle, the camera 11 can be a controllable camera, which can be mounted on the roof of the vehicle. For example, this controllable camera can be replaced with a lidar, millimeter-wave radar, or ultrasonic radar, which is more conducive to road recognition in rainy and snowy weather. Furthermore, if some embodiments of the present disclosure are applied to an unmanned vehicle, since the unmanned vehicle itself is equipped with a corresponding radar, recognition data can be directly obtained from the unmanned system.

Furthermore, the controllable camera's acquisition angle can be correlated with the vehicle's speed. In other words, the controllable camera's recognition distance, and thus the camera's acquisition angle, can be adjusted based on vehicle speed. At higher vehicle speeds, the angle α between the controllable camera and the horizontal plane decreases, increasing the preview distance and thus allowing sufficient response time for the suspension system. Conversely, at lower vehicle speeds, the angle α can be increased, thereby improving the controllable camera's recognition accuracy. The corresponding control method can be integrated into control module 3.

As shown in Figure 1 , the information acquisition module 1 may also include a vehicle ECU 12. When the vehicle is in motion, the control module 3 may obtain vehicle information from the vehicle ECU 12 and adjust the angle of the controllable camera based on the vehicle speed v contained in the vehicle information. For example, the value of the controllable camera angle α can be calculated using the following formula:

Where x is the maximum distance at which the controllable camera can clearly and accurately capture road conditions. y is the maximum camera range of the controllable camera (i.e., the camera limit value). The camera limit value may include, for example, the pixel limit value, focal length limit value, and aperture limit value of the camera 11. _tk and _tc are the response times of the variable-stiffness air spring 45 and the magnetorheological damper 46, respectively. For example, the response time _tk of the variable-stiffness air spring 45 may be 10 seconds, and the response time _tc of the magnetorheological damper 46 may be 1 second. _tcon is the signal transmission time between the controllable camera and the control module 3.

Step S120 : performing a second adjustment on the stiffness parameter of at least one of the multiple shafts of the suspension system according to the road surface information and the operating condition parameters.

For example, stiffness parameters can include the stiffness and offset frequency of each axle. Offset frequency is an important parameter for evaluating the ride comfort of the entire vehicle and refers to the maximum frequency that the suspension system can withstand during driving.

In some embodiments, the control methods of some embodiments of the present disclosure are divided into high-speed mode and precise mode according to the size of the vehicle's driving speed v and the speed threshold v _0. That is, when the vehicle speed v ≤ v ₀ , the control module 3 executes the precise mode, otherwise it executes the high-speed mode. In the precise mode, the second adjustment is performed simultaneously with the first adjustment. In the high-speed mode, the second adjustment is performed after the first adjustment. Some embodiments of the present disclosure propose two control methods, high-speed mode and precise mode, according to the different vehicle speeds v. Compared with the relevant technologies, it not only increases the applicability in different speed ranges, but also improves the accuracy of optimizing vehicle smoothness in different speed ranges, reduces unnecessary shaking, and the number of times the suspension and body are worn, and extends the service life of the vehicle.

The high-speed mode is suitable for situations where the system needs to respond quickly when the vehicle is traveling at high speed. Since the response time _tk of the variable-stiffness air spring 45 is slower than the response time _tc of the magnetorheological shock absorber 46, in the high-speed mode, the adjustment of the damping matching mode of each axis with a faster response is completed in advance, and then the adjustment of the damping matching mode of each axis with a slower response is completed according to the changes in road conditions. The precise mode is suitable for situations where the vehicle is traveling at medium and low speeds. Since the system has sufficient time to adjust the matching mode of the stiffness and damping of each axis, the suspension stiffness and damping are adjusted according to the changes in road conditions. The two control modes in some embodiments of the present disclosure can ensure that the smoothness adjustment of the vehicle is fast enough when traveling at high speeds, Compared with related technologies, the control method of some embodiments of the present disclosure has stronger adaptability in optimizing ride comfort, avoiding discomfort to passengers caused by the slow response of the active suspension.

In some embodiments, the speed threshold v ₀ can be expressed as:

Where y is the maximum camera range of the controllable camera. _{L H} is the height of the controllable camera from the road surface. L is the horizontal distance between the controllable camera and the front wheel of the vehicle. _tk is the response time of the variable-stiffness air spring 45, which can be, for example, 10 seconds. _tcon is the signal transmission time between the controllable camera and the control module 3.

When the precise mode is executed, that is, when the vehicle's speed v is less than or equal to the speed threshold v ₀ , the second adjustment is performed simultaneously with the first adjustment. When the precise mode is executed, the second adjustment of the stiffness parameters of at least one of the multiple axes of the suspension system may include step S121 or step S122.

Step S121: When the wading depth H is greater than the depth threshold, or when the road surface information is a random road surface, or when the road surface information is a pulse road surface, the tire pressure P is less than or equal to the tire pressure threshold, and the wheel angle When the rotation angle is less than or equal to the rotation angle threshold, the stiffness parameters of the multiple axes are adjusted so that the offset frequency of each axis in the multiple axes is equal.

For example, when executing precision mode, the control module 3 first determines whether the vehicle's wading depth H reaches a depth threshold H ₀ based on the water level information obtained by the water level sensor 13. The depth threshold H ₀ indicates the height at which the road surface water level may enter the vehicle compartment. If H>H ₀ , the suspension system must ensure that the suspension travel is the primary evaluation parameter while ensuring smoothness and limiting the suspension travel. Since the suspension travel is minimized when the suspension offset frequency is the same and the damping of each axis is equal, if the wading depth H is greater than the depth threshold H ₀ , the control module 3 adjusts the suspension stiffness to achieve equal offset frequency and damping C ₁ to C ₆ on each axis.

If H≤H ₀ , it means that the wading depth H does not reach the depth threshold H ₀ . At this time, it can be determined that the vehicle is not in the wading state. Then it is necessary to determine whether the tire pressure P is less than the tire pressure threshold and the wheel angle. Is it less than the turning angle threshold? If not, it indicates that the tire pressure P is too high or the vehicle is turning. In this case, wheel dynamic load is a key consideration in the ride comfort evaluation parameters. Excessive wheel dynamic load, resulting from excessive tire pressure P and tire size, reduces the tire's contact patch and creates the risk of a blowout. Furthermore, insufficient grip during steering can create the risk of drifting. Because wheel dynamic load is minimized when the suspension's offset frequency is equal on random road surfaces, control module 3 determines the road surface type and then implements the appropriate stiffness and damping scheme.

If the vehicle is neither wading nor turning, or the tire pressure is too high, the vehicle body acceleration is the primary evaluation metric. Since vehicle body acceleration is minimized when the suspension's deflection frequency is constant on any road surface, the program executes the appropriate action based on the road surface condition.

Therefore, when the wading depth H is greater than the depth threshold _H0 , or when the road surface information is a random road surface, or when the road surface information is a pulse road surface, the tire pressure P is less than or equal to the tire pressure threshold, and the wheel angle When the rotation angle is less than or equal to the rotation angle threshold, the stiffness parameters of the multiple axes are adjusted so that the offset frequency of each axis in the multiple axes is equal.

In the case where the suspension system includes three axes, the offset frequency of each of the multiple axes is equal to the following formula:

k ₁ ＝k ₂ k ₃ ＝k ₄ k ₅ ＝k ₆ ,

Among them, _m1 is the sprung mass of the front axle among the three axles, _m2 is the sprung mass of the middle axle among the three axles, and _m3 is the sprung mass of the rear axle among the three axles. The sprung mass of the axle; k1 _{to k6} are the variable stiffnesses of the variable stiffness air springs 45 corresponding to the six wheels 47 in the suspension structure 4. _k1 and _k2 are the stiffnesses of the two wheels corresponding to the front axle, _k3 and _k4 are the stiffnesses of the two wheels corresponding to the middle axle, and _k5 and _k6 are the stiffnesses of the two wheels corresponding to the rear axle.

Step S122: When the wading depth H is less than or equal to the depth threshold H ₀ , the road surface information is a pulse road surface, and the tire pressure P is greater than the tire pressure threshold or the wheel angle When the rotation angle is greater than the angle threshold, the stiffness parameters of the multiple axes are adjusted so that the stiffness of the middle axis of the multiple axes is the largest.

For example, as mentioned above, when executing the precise mode, if H≤H ₀ , it means that the wading depth H does not reach the depth threshold H _0. At this time, it can be determined that the vehicle is not in a wading state, and the vehicle body acceleration needs to be considered as an evaluation indicator. Because the intermediate shaft stiffness is large (such as maximum) under the pulse road surface and the damping ratio of each shaft is equal, the dynamic load of the wheel is the smallest. Therefore, when the wading depth H is less than or equal to the depth threshold H ₀ , the road surface information is a pulse road surface, and the tire pressure P is greater than the tire pressure threshold or the wheel angle When the rotation angle is greater than the angle threshold, the stiffness parameters of the multiple axes are adjusted so that the stiffness of the middle axis of the multiple axes is the maximum, and the damping parameters of the multiple axes are adjusted so that the damping of the middle axis is the maximum.

When the high-speed mode is in effect, that is, when the vehicle's speed v is greater than the speed threshold v ₀ , the second adjustment is performed after the first adjustment. In other words, the execution logic of the program flow executed by the control module 3 in the high-speed mode is similar to that of the precise mode described above, but under different road conditions, the damping-related adjustments are performed first.

In this case, the first adjustment can also include adjusting the damping parameter multiple times. For example, the damping parameter is first adjusted ten times, and then a determination is made as to whether to adjust the stiffness parameter. Because the damping adjustment is 10 times faster than the stiffness adjustment, the control system (e.g., control module 3) needs to compare the status of the current control determination cycle with the status of the 10 control determination cycles preceding the current determination cycle. If the status is the same, the stiffness parameter can be adjusted; if it is different, the stiffness response time cannot be met, and the stiffness parameter adjustment is not performed.

Additionally, when executing high-speed mode, performing a second adjustment on the stiffness parameters of at least one of the multiple axes of the suspension system may include step S123, step S124, or step S125. Thus, some embodiments of the present disclosure, through the combination of information acquisition module 1 and control module 3, are applicable not only to common road surfaces but also to vehicle smoothness adjustment under conditions such as excessive tire pressure and steering, and even under special wading conditions. Compared to related technologies, some embodiments of the present disclosure can ensure smoothness in a wider range of road conditions, allowing the vehicle to provide passenger comfort at all times regardless of road conditions.

Step S123 , when the road surface information and the working condition parameters of the vehicle corresponding to each of the multiple adjustments meet the first set condition, the stiffness parameters of the multiple shafts are adjusted so that the stiffness of the middle shaft of the multiple shafts is the maximum.

For example, the first setting condition is: the road surface information is a random road surface, the wading depth H is less than or equal to the depth threshold H ₀ , and the tire pressure P is greater than the tire pressure threshold or the wheel angle If the wading depth H does not reach the depth threshold H ₀ , then determine whether the tire pressure P is greater than the tire pressure threshold P ₀ and the wheel angle Is it greater than the corner threshold? If the answer is yes, it means the tire pressure P is too high or the vehicle is turning. In this case, wheel dynamic load is a key consideration in the ride comfort evaluation parameters. Excessive wheel dynamic load, resulting from excessive tire pressure P and tire size, reduces the tire's contact patch and creates the risk of a blowout. Furthermore, insufficient grip during a turn can create the risk of a spin. Therefore, on random roads, when tire pressure P is too high or the wheels are turning, the suspension stiffness should be adjusted to maximize the center axle stiffness. All other adjustments involve adjusting the suspension stiffness to equalize the offset frequencies of all axles.

In the case where the number of adjustments mentioned above is ten, if the road surface information and operating parameters of the vehicle corresponding to the first ten adjustments meet the first set condition mentioned above, the suspension stiffness needs to be adjusted to the maximum intermediate shaft stiffness. It can be seen that a larger tire dynamic load will cause the tire contact area to become smaller, and the tire's ground adhesion will decrease, while excessive tire pressure will increase the trend of the tire's ground adhesion decreasing, resulting in increased tire bounce and the risk of the tire leaving the ground. Moreover, if the wheel is in a steering state at this moment, it will increase the risk of the vehicle slipping, skidding, and other loss of control. Therefore, some embodiments of the present disclosure adopt a control method that minimizes the dynamic load of the tire to address this phenomenon, which can reduce the ride comfort while improving the ride comfort. Reduce the risk of vehicle loss of control and improve vehicle handling stability.

Step S124 , when the road surface information and the operating condition parameters of the vehicle corresponding to each of the multiple adjustments meet the second set condition, the stiffness parameters of the multiple shafts are adjusted to have the same offset frequency for each of the multiple shafts.

The second setting condition is: the road surface information is a pulse road surface, the wading depth H is greater than the depth threshold H ₀ , or the tire pressure P is less than or equal to the tire pressure threshold and the wheel angle Less than or equal to the turning angle threshold. It can be seen that the second set condition is all operating conditions except the first set condition. In other words, the road surface information and operating condition parameters of the vehicle corresponding to each adjustment in the multiple adjustments either meet the first set condition or the second set condition.

In the case where the number of adjustments is ten, if the road surface information and operating parameters of the vehicle corresponding to the first ten adjustments all meet the second setting condition, the suspension stiffness needs to be adjusted until the offset frequencies of the various axes are equal.

In step S125, when the road surface information and operating condition parameters of the vehicle corresponding to any one of the multiple adjustments meet the first set condition, and the road surface information and operating condition parameters of the vehicle corresponding to another one of the multiple adjustments meet the second set condition, the stiffness parameters of the multiple shafts are not adjusted.

In the case where the above-mentioned multiple adjustments are ten times, if the road surface information and operating parameters of the vehicle corresponding to the first ten adjustments neither fully meet the first setting condition nor fully meet the above-mentioned second setting condition, it is determined that the stiffness response time cannot be met and no stiffness adjustment is performed.

Step S130 , performing a third adjustment on the control force parameters of at least one of the multiple axes of the suspension system according to the road surface excitation information, the operating state parameters, and the weight matrix corresponding to the working condition parameters of the vehicle.

The third adjustment is performed after the second adjustment. That is, steps S110 and S120 are pre-adjustments of the vehicle's suspension system, while step S130 is a secondary adjustment of the vehicle's suspension system. At the same time, step S130 needs to be implemented based on the dynamic calculation module 2, while steps S110 and S120 do not need to be implemented based on the dynamic calculation module 2. Therefore, the control method provided in some embodiments of the present disclosure can use electronic control to achieve pre-adjustment of the suspension structure 4 before the dynamic calculation module 2 intervenes. On the one hand, compared with related technologies, such an adjustment method can achieve a smoother state more quickly and improve the comfort of the vehicle more quickly. On the other hand, compared with related technologies, some embodiments of the present disclosure complete the pre-adjustment without calculation by the dynamic module 2, so it has a faster response speed, solves the problem of response lag caused by complex dynamic calculations, and allows passengers to enter a comfortable state more quickly.

For example, suspension structure 4 transmits road excitation information from wheel 47 to vehicle ECU 12, which then transmits vehicle information to dynamics calculation module 2. Dynamics calculation module 2 outputs a force control signal to control module 3, which then controls force controller 44 to adjust the control forces on front axle 41, intermediate axle 42, and rear axle 43, respectively, achieving secondary adjustment of the active suspension system.

In some embodiments, performing a third adjustment on a control force parameter of at least one of the plurality of axes of the suspension system may include steps S131 to S134 .

Step S131 : determining a first relationship between an output matrix of the suspension system and an active control force matrix of the suspension system according to a road surface excitation matrix corresponding to the road surface excitation information and an operating state matrix corresponding to the operating state parameters.

For example, the dynamics calculation module 2 can be used to perform calculations based on the dynamics model shown in FIG5. The dynamics calculation module 2 is based on a 9-degree-of-freedom vehicle model. The 9 degrees of freedom include the vertical displacement Z of the vehicle body, the pitch angle θ of the vehicle body, the roll angle θ of the vehicle body, and the vertical displacement Z of the vehicle body. And the six wheel vertical displacements Z _wi , i=1, 2, 3, 4, 5, 6.

As shown in Figure 5, the center of mass of the three-axle vehicle body is located between the front axle 41 and the intermediate axle 42, and the body coordinate system maintains the same direction as the vehicle coordinate system. The force controller 44 is simplified to control force units U ₁ to U ₆ . The six wheels 47 are respectively equipped with masses m _wfl , m _wfr , m _wml , m _wmr , and m _{wrl . The six rigid bodies kw1 to kw6 are used} to replace the tire vertical stiffness, and the road surface excitations are _Zr1 to _Zr6 .

According to Newton's second law, the kinematic equations for the vehicle body's pitch, roll, and vertical motion of the center of mass are:

Where a, b, and c are the distances from the front axle 41, intermediate axle 42, and rear axle 43 to the center of mass of the vehicle body, respectively. l is the wheelbase. _Iθ is the moment of inertia about the y-axis. is the moment of inertia about the x-axis. m _b is the vehicle body mass. _{F b1} to F _b6 are the vertical forces acting on the six wheels 47 of the vehicle body, respectively. The vehicle body force matrix F can be used to represent the forces acting on the vehicle body and wheels, namely:
F＝[F _b1 F _b2 F _b3 F _b4 F _b5 F _b6 ] ^T

The vehicle body force matrix F is calculated by the following formula:

Where K and C are the suspension stiffness matrix and suspension damping matrix, respectively. _Zb and _Zw are the body displacement matrix and tire displacement matrix, respectively. U is the active control force matrix. Each matrix is expressed as follows:

Z _w = [Z _w1 Z _w2 Z _w3 Z _w4 Z _w5 Z _w6 ] ^T
Z _b ＝[Z _b1 Z _b2 Z _b3 Z _b4 Z _b5 Z _b6 ] ^T
U＝[U ₁ U ₂ U ₃ U ₄ U ₅ U ₆ ] ^T

Wherein, Z _b1 to Z _b6 are vertical displacements of the vehicle body at positions corresponding to the six wheels 47 .

The vertical kinematic equation of the wheel is:

Where _Kw is the wheel stiffness matrix, and _Zr is the road excitation matrix (the road excitation matrix is transmitted to the vehicle ECU 12 through the suspension structure 4 and then transmitted to the dynamic calculation module 2), which are respectively expressed as:

Z _r ＝[Z _r1 Z _r2 Z _r3 Z _r4 Z _r5 Z _r6 ] ^T

Based on the vehicle's ride comfort index, the vehicle body acceleration, pitch acceleration, suspension travel, and wheel vertical displacement are selected as the output matrix Y. That is, the output matrix Y can include the vehicle's body acceleration, pitch acceleration, suspension travel, and wheel vertical displacement. The vehicle's driving state is acquired by the vehicle ECU 12 of the information acquisition module 1 and then input into the operating state matrix X of this dynamics calculation module 2. The operating state matrix X includes the vertical displacement of the center of mass, vertical velocity, pitch angle, pitch velocity, wheel vertical displacement, and wheel vertical velocity values. Therefore, the output matrix Y and the operating state matrix X can be expressed as follows:

Combining the kinematic equations of the vehicle body and the vertical kinematic equations of the wheels, we can obtain:

Among them: A, B, D are the coefficient matrices of the operating state matrix X, the road excitation matrix Z _r , and the active control force matrix U. Combined with the suspension motion stroke S _i and tire deformation W _i, they are:
S _i ＝Z _i -Z _ri (i＝1,2,3,4,5,6)
W _i ＝Z _wi -Z _ri (i＝1,2,3,4,5,6)

Therefore, the first relationship between the output matrix Y of the suspension system and the active control force matrix U of the suspension system can be expressed as follows:
Y＝PX+QZ _r +RU，

Among them, X is the operating state matrix, _Zr is the road surface excitation matrix, P is the first coefficient matrix of the operating state matrix X, Q is the second coefficient matrix of the road surface excitation matrix _Zr , and R is the third coefficient matrix of the active control force matrix U.

The dynamic calculation module 2 provided in some embodiments of the present disclosure matches the suspension matching strategy of a multi-axle vehicle (e.g., a three-axle bus) through a 9-degree-of-freedom model, providing a method for pre-adjusting the stiffness and damping of the active suspension system of the multi-axle vehicle, thereby solving the problem of the lack of pre-adjustment method for the active suspension of the multi-axle vehicle and providing a set of optimization methods for the multi-axle vehicle that can quickly improve the smoothness.

Step S132: Determine a second relationship between the comprehensive score of the suspension system and the active control force matrix based on the first relationship, the evaluation parameter score corresponding to the output matrix, and the weight matrix corresponding to the vehicle's operating parameters. The second relationship can be expressed as follows:

Among them, _Nw is the comprehensive score of the suspension system, _Ni is the evaluation parameter score corresponding to the output matrix Y, and Sj _,i is the weight matrix corresponding to the vehicle's operating parameters;

In the case of a suspension system comprising three axles, j=1, 2, 3 and n=14.

Since the evaluation indicators of smoothness will be different under different road conditions and road surface conditions, three groups of weight matrices S _1,i , S _2,i and S _3,i are introduced. The three groups of weight matrices are expressed as follows:

Among them, when the wading height H is less than or equal to the depth threshold H ₀ , the tire pressure P is less than or equal to the tire pressure threshold, and the wheel angle When the wading height H is less than or equal to the depth threshold H ₀ and the tire pressure P is greater than the tire pressure threshold or the wheel angle, the weight matrix S _ji is the first weight matrix S _1,i . When the wading height H is greater than the depth threshold H 0, the weight matrix S _ji is the second weight matrix S _2,i . When the wading height H is greater than the depth threshold H ₀ , the weight matrix S _ji is the third weight matrix S _3,i .

As can be seen, some embodiments of the present disclosure provide a set of weight matrices for the dynamics calculation module 2, adapting the ride comfort evaluation method to different road conditions, thereby optimizing specific ride comfort parameters. Therefore, compared to related technologies, some embodiments of the present disclosure offer a more flexible optimization approach, allowing for the optimization of specific parameters while simultaneously considering various ride comfort indicators. This allows for comprehensive improvements in vehicle ride comfort under varying road conditions. Furthermore, this approach ensures passenger safety while also enhancing comfort under challenging road conditions.

Step S133 : According to the second relationship, the active control force matrix that maximizes the comprehensive score is determined as the target control force matrix of the suspension system.

The control module 3 can adjust the active control force matrix U to maximize the comprehensive score _Nw of the suspension system, thereby achieving the purpose of re-adjusting the vehicle ride comfort.

Step S134 : adjusting the control force parameters of at least one of the multiple axes of the suspension system according to the target control force matrix.

For example, when vehicle speed v ≤ v ₀ , control module 3 executes precision mode; otherwise, it executes high-speed mode. When executing precision mode, control module 3 first determines whether the vehicle's wading depth H reaches a depth threshold H _0. H ₀ represents the height at which road water may enter the vehicle cabin. If the wading depth H exceeds the depth threshold H ₀ , the system must ensure smoothness while maintaining suspension travel as the primary evaluation parameter, limiting the suspension travel. Because suspension travel is minimized when the suspension offsets are the same and the damping on each axis is equal, if the wading depth H exceeds the depth threshold H ₀ , control module 3 adjusts the suspension stiffness parameters to equalize the offsets on each axis and adjusts the damping parameters to equalize the damping C ₁ to C _6. Subsequently, control module 3 sets the weight matrix of the output matrix to the third weight matrix S _3,i .

Then, the active control force matrix U is adjusted according to the size of the comprehensive score _Nw . Finally, the number of cycles is counted, and the number of cycles is increased by one (such as n=n+1) to return the judgment on whether the vehicle is started.

If the wading height H does not reach the depth threshold H ₀ , the tire pressure P is judged to be less than the tire pressure threshold and the wheel angle. Is it less than the turning angle threshold? If the judgment is negative, it indicates that the tire pressure P is too high or the vehicle is in a turning state. In this case, wheel dynamic load is a key consideration in the ride comfort evaluation parameters. When wheel dynamic load is excessive, excessive tire pressure and tire size reduce the tire's contact patch and increase the risk of a blowout. Furthermore, insufficient grip during vehicle steering can increase the risk of drifting. Because wheel dynamic load is minimized when the suspension's offset frequency is equal and the damping of each axle is equal on a random road surface, or when the intermediate shaft stiffness is high (e.g., maximum) and the damping ratios of each axle are equal on an impulsive road surface, the corresponding stiffness and damping scheme is implemented after determining the road surface type. Subsequently, control module 3 sets the weight matrix of the output matrix to the second weight matrix S _2,i , following the same process as described above. The active control force matrix U is then adjusted, and the vehicle is returned to determine whether it has started.

If the vehicle is neither in a wading state nor in a turning state or the tire pressure is too high, the vehicle body acceleration is the key evaluation index. That is, the wading depth H, tire pressure P and wheel angle Neither reaches the corresponding threshold. Because vehicle acceleration is minimized when the suspension's offset frequencies are equal and the damping ratios of each axle are equal on a random road surface, or when the offset frequencies are equal and the intermediate axle damping is large (e.g., maximum) on an impulsive road surface, the program then determines the road surface condition, performs the corresponding operation, sets the output matrix's weight matrix to the first weight matrix S _1,i, and repeats the above steps.

If it is judged to be high speed mode, the program flow execution logic is similar to that of the precise mode, but only the damping-related adjustments are performed under different road conditions. In addition, when the tire pressure is too high or the vehicle is in a turning state on a random road, the parameter Sn is assigned to 1, and is assigned to 0 under other road conditions. To determine whether stiffness adjustment is necessary after multiple damping adjustments in high-speed mode. This is because damping adjustment is 10 times faster than stiffness adjustment, and only when Sn = 1 does the suspension stiffness parameter need to be adjusted to maximize the intermediate shaft stiffness; all other operations involve adjusting the suspension stiffness parameters to equalize the offset frequencies of each shaft. Therefore, the control system compares the status of the current cycle with the status of the previous 10 cycles. If the status is the same, the stiffness parameter can be adjusted, and the stiffness adjustment method is selected based on the value of Sn. If the status is different, the stiffness response time cannot be met, and stiffness adjustment is not performed. The control system then performs the same operations as in precision mode, adjusting the active control force matrix U to optimize vehicle smoothness.

In summary, the overall flow chart of the control method of the control module 3 is shown in FIG6. The control module 3 first calls the vehicle speed v, the steering wheel angle, and the vehicle ECU. The system uses vehicle information, including tire pressure P, to adjust the controllable camera angle based on vehicle speed v. The entire control method is divided into two modes: high-speed mode and precise mode. The high-speed mode is suitable for situations where a fast system response is required during high-speed driving. Because the variable-stiffness air spring 45 has a slower response time than the magnetorheological damper 46, the high-speed mode pre-adjusts the damping matching scheme for each axis with a faster response. It then adjusts the damping matching scheme for each axis with a slower response based on changing road conditions. Finally, the weight matrix S _j,i is used to adjust the control force. The precise mode is suitable for situations where the vehicle is traveling at medium and low speeds. Because the system has ample time to adjust the stiffness and damping matching scheme for each axis, it adjusts the suspension stiffness and damping based on changing road conditions. Similarly, the active control force matrix U is adjusted based on the weight matrix S _j,i used to adjust the road condition matching scheme.

Therefore, some embodiments of the present disclosure provide three optimization methods for smoothness, namely stiffness, damping and force control. Damping adjustment has the effect of rapid response, reducing roll and shake during sharp turns and high speeds, reducing wear on the suspension and body, and extending the service life of the vehicle. Stiffness adjustment has the effect of solving the tire contact area and affecting the smoothness and handling stability of the vehicle. Force control adjustment has the effect of making each smoothness evaluation parameter reach the optimal value at the same time or focusing on a certain evaluation parameter. Therefore, compared with the related art, some embodiments of the present disclosure have these three adjustment methods at the same time, so that the active suspension can ensure rapid response of the system while making the vehicle have better smoothness and handling stability and a more comprehensive smoothness optimization effect.

On the other hand, some embodiments of the present disclosure further provide a control system 200 for a vehicle suspension system. As shown in FIG7 , the control system 200 may include: at least one of a first adjustment device 210 or a second adjustment device 220 , and a third adjustment device 230 .

The first adjustment device 210 is configured to perform a first adjustment on the damping parameter of at least one of the multiple shafts of the suspension system according to road surface information ahead of the vehicle and operating parameters of the vehicle.

The second adjusting device 220 is configured to perform a second adjustment on the stiffness parameter of at least one of the multiple shafts of the suspension system according to the road surface information and the operating condition parameters.

The third adjustment device 230 is configured to perform a third adjustment on the control force parameters of at least one of the multiple axes of the suspension system according to the road surface excitation information, the operating state parameters and the weight matrix corresponding to the working condition parameters of the vehicle.

On the other hand, the present disclosure further provides a vehicle, which may include the control system of the suspension system described above.

Regarding the control system of the vehicle suspension system and the beneficial effects of the vehicle provided by some embodiments of the present disclosure, reference may be made to the above description of the control method of the vehicle suspension system, which will not be repeated here.

In another aspect, an embodiment of the present disclosure provides an electronic device. The electronic device includes at least one processor and a memory. The memory is connected to the at least one processor. The memory stores instructions executable by the at least one processor. The at least one processor implements the above-described method for controlling a vehicle suspension system by executing the instructions stored in the memory.

The memory may include a non-permanent memory in a computer-readable medium, at least one of a random access memory (RAM) or a non-volatile memory, such as a read-only memory (ROM) or a flash RAM, and the memory includes at least one memory chip.

An embodiment of the present disclosure provides a processor configured to run a program. When the program is run, the method for controlling the suspension system of the vehicle is executed.

On the other hand, an embodiment of the present disclosure provides a machine-readable storage medium having a program stored thereon, which implements the control method of the suspension system of the vehicle when executed by a processor.

It will be understood by those skilled in the art that the embodiments of the present disclosure may be provided as methods, systems, or computer program products. Thus, the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present disclosure may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, compact disc read-only memory (CD-ROM), optical storage, etc.) containing computer-usable program code.

The present disclosure is described with reference to the flowcharts and/or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present disclosure. It should be understood that each process and/or box in the flowchart and/or block diagram, as well as the combination of the processes and/or boxes in the flowchart and/or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the functions specified in one or more processes in the flowchart and/or one or more boxes in the block diagram.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction device that implements the functions specified in one or more processes in the flowchart and/or one or more boxes in the block diagram.

These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and/or one or more boxes in the block diagram.

In a typical configuration, a computing device includes one or more processors (Central Processing Unit, CPU), input/output interfaces, network interfaces, and memory.

The memory may include at least one of a non-permanent memory, random access memory (RAM), or non-volatile memory such as read-only memory (ROM) or flash RAM in a computer-readable medium. Memory is an example of a computer-readable medium.

Computer-readable media includes both permanent and non-permanent, removable and non-removable media, and can be implemented by any method or technology for information storage. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change random access memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical storage, magnetic cassettes, magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined in this article, computer-readable media does not include transitory media such as modulated data signals and carrier waves.

It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover a non-exclusive inclusion, such that A process, method, product, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, product, or apparatus. In the absence of further limitations, an element defined by the phrase "including a..." does not preclude the presence of other identical elements in the process, method, product, or apparatus that includes the element.

The above are merely examples of the present disclosure and are not intended to limit the present disclosure. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure are intended to be included within the scope of the claims of the present disclosure.

Claims (13)

A method for controlling a suspension system of a vehicle, comprising at least one of the following: performing a first adjustment on a damping parameter of at least one of the plurality of shafts of the suspension system according to road surface information ahead of the vehicle and an operating parameter of the vehicle; or performing a second adjustment on a stiffness parameter of at least one of the plurality of shafts of the suspension system according to the road surface information and the operating condition parameter; The control method further includes: performing a third adjustment on a control force parameter of at least one of the multiple axes of the suspension system according to the road surface excitation information of the vehicle, the operating state parameters and the weight matrix corresponding to the operating condition parameters. The control method according to claim 1, wherein the road surface information includes pulsed road surface and random road surface, the operating condition parameters include wading depth, tire pressure, and wheel angle of the vehicle, and the first adjustment of the damping parameter of at least one of the multiple axes of the suspension system includes one of the following: When the wading depth is greater than a depth threshold, or when the road surface information is the random road surface and the tire pressure is greater than a tire pressure threshold or the wheel angle is greater than an angle threshold, adjusting the damping parameters of the multiple axes so that the damping of each of the multiple axes is equal; When the wading depth is less than or equal to the depth threshold, the road surface information is the pulse road surface, and the tire pressure is greater than the tire pressure threshold, or the wheel rotation angle is greater than the rotation angle threshold, or when the wading depth is less than or equal to the depth threshold, the road surface information is the random road surface, the tire pressure is less than or equal to the tire pressure threshold, and the wheel rotation angle is less than or equal to the rotation angle threshold, adjusting the damping parameters of the multiple axles so that the damping ratio of each axle is equal; wherein the damping ratio of each axle is related to the damping, stiffness, and sprung mass of the axle; and When the wading depth is less than or equal to the depth threshold, the road surface information is the pulse road surface, the tire pressure is less than or equal to the tire pressure threshold, and the wheel angle is less than or equal to the angle threshold, the damping parameters of the multiple shafts are adjusted so that the damping of the middle shaft of the multiple shafts is the maximum. The control method according to claim 2, wherein, in the case where the suspension system includes three axes, the damping ratio of each axis is expressed by the following equation:

Wherein, _ζ1 is the damping ratio of the front axle among the three axles, _ζ2 is the damping ratio of the intermediate axle among the three axles, _{and ζ3} is the damping ratio of the rear axle among the three axles; _m1 is the sprung mass of the front axle, _m2 is the sprung mass of the intermediate axle, and _m3 is the sprung mass of the rear axle; _Cm1 is the output parameter of the shock absorber of the front axle, _Fm1 is the average value of the restoring resistance and the compression resistance of the shock absorber of the front axle, _vm1 is the speed corresponding to the moment of _Fm1 , and _D1 is the design parameter of the shock absorber of the front axle; _Cm2 is the output parameter of the shock absorber of the intermediate axle, _Fm2 is the average value of the restoring resistance and the compression resistance of the shock absorber of the intermediate axle, _vm2 is the speed corresponding to the moment of _Fm2 , and D2 is the design parameter of the shock absorber of the intermediate axle; _Cm3 is the output parameter of the shock absorber of the rear axle, _Fm3 is the average value of the restoring resistance and the compression resistance of the shock absorber of the rear axle, and _vm3 is the speed corresponding to the _moment of Fm1. _m3 is the speed corresponding to the moment, _D3 is the design parameter of the shock absorber of the rear axle; _k1 and _k2 are the stiffness of the two wheels corresponding to the front axle, _k3 and _k4 are the stiffness of the two wheels corresponding to the intermediate axle, _k5 and _k6 are the stiffness of the two wheels corresponding to the rear axle. The control method according to claim 2 or 3, further comprising: when the driving speed of the vehicle is less than or equal to a speed threshold, performing the second adjustment simultaneously with the first adjustment, wherein the stiffness parameters include stiffness and offset frequency, The second adjustment of the stiffness parameter of at least one of the plurality of shafts of the suspension system comprises one of the following: When the wading depth is greater than the depth threshold, or when the road surface information is the random road surface, or when the road surface information is the pulsed road surface, the tire pressure is less than or equal to the tire pressure threshold, and the wheel angle is less than or equal to the angle threshold, adjusting the stiffness parameters of the multiple shafts so that the offset frequency of each of the multiple shafts is equal; and When the wading depth is less than or equal to the depth threshold, the road surface information is the pulse road surface, and the tire pressure is greater than the tire pressure threshold or the wheel angle is greater than the angle threshold, the stiffness parameters of the multiple shafts are adjusted so that the stiffness of the middle shaft of the multiple shafts is the maximum. The control method according to claim 2 or 3, further comprising: when the driving speed of the vehicle is greater than a speed threshold, the second adjustment is performed after the first adjustment, wherein the first adjustment further comprises adjusting the damping parameter multiple times, The second adjustment of the stiffness parameter of at least one of the plurality of shafts of the suspension system comprises one of the following: When the road surface information and the operating condition parameters of the vehicle corresponding to each adjustment in the multiple adjustments meet a first set condition, the stiffness parameters of the multiple axles are adjusted so that the stiffness of the middle axle of the multiple axles is the maximum; wherein the first set condition is: the road surface information is the random road surface, the wading depth is less than or equal to the depth threshold, and the tire pressure is greater than the tire pressure threshold or the wheel angle is greater than the angle threshold; When the road surface information and the operating condition parameters of the vehicle corresponding to each adjustment in the multiple adjustments meet a second set condition, the stiffness parameters of the multiple shafts are adjusted so that the offset frequency of each of the multiple shafts is equal; wherein the second set condition is: the road surface information is the pulse road surface, the wading depth is greater than the depth threshold, or the tire pressure is less than or equal to the tire pressure threshold and the wheel angle is less than or equal to the angle threshold; and When the road surface information and the operating condition parameters of the vehicle corresponding to any one of the multiple adjustments meet the first setting condition and the road surface information and the operating condition parameters of the vehicle corresponding to another one of the multiple adjustments meet the second setting condition, the stiffness parameters of the multiple shafts are not adjusted. The control method according to claim 4 or 5, wherein, in the case where the suspension system includes three axes, the offset frequency of each of the plurality of axes is equal to the following formula:

k ₁ ＝k ₂ k ₃ ＝k ₄ k ₅ ＝k ₆ , Wherein, _m1 is the sprung mass of the front axle among the three axles, _m2 is the sprung mass of the middle axle among the three axles, _{and m3} is the sprung mass of the rear axle among the three axles; _k1 and _k2 are the stiffnesses of the two wheels corresponding to the front axle, _k3 and _k4 are the stiffnesses of the two wheels corresponding to the middle axle, and _k5 and _k6 are the stiffnesses of the two wheels corresponding to the rear axle. The control method according to any one of claims 2 to 5 further includes: identifying the road surface information as the pulse road surface or the random road surface by a camera installed on the vehicle, wherein the acquisition angle of the camera is fixed or variable, and when the acquisition angle is variable, the acquisition angle is related to the driving speed of the vehicle. The control method according to any one of claims 1 to 7, wherein the third adjustment of the control force parameter of at least one of the multiple axes of the suspension system comprises: Determining a first relationship between an output matrix of the suspension system and an active control force matrix of the suspension system based on a road surface excitation matrix corresponding to the road surface excitation information and an operating state matrix corresponding to the operating state parameters; wherein the output matrix includes body acceleration, pitch angular acceleration, suspension travel, and wheel vertical displacement of the vehicle, and the operating state matrix includes vertical displacement of the center of mass, vertical velocity, pitch angle, pitch angular velocity, wheel vertical displacement, and wheel vertical velocity values of the vehicle; determining a second relationship between the comprehensive score of the suspension system and the active control force matrix based on the first relationship, the evaluation parameter score corresponding to the output matrix, and the weight matrix corresponding to the operating condition parameter of the vehicle; According to the second relationship, determining the active control force matrix that maximizes the comprehensive score as the target control force matrix of the suspension system; and A control force parameter of at least one axis among the multiple axes of the suspension system is adjusted according to the target control force matrix. The control method according to claim 8, wherein the first relationship and the second relationship satisfy at least one of the following: The first relationship is expressed as follows:
Y＝PX+QZ _r +RU， Wherein, Y is the output matrix of the suspension system, U is the active control force matrix of the suspension system, X is the operating state matrix, Z _r is the road surface excitation matrix, P is the first coefficient matrix of the operating state matrix X, Q is the second coefficient matrix of the road surface excitation matrix Z _r , and R is the third coefficient matrix of the active control force matrix U; or The second relationship is expressed as follows:
Wherein, _Nw is the comprehensive score of the suspension system, _Ni is the evaluation parameter score corresponding to the output matrix Y, and Sj _,i is the weight matrix corresponding to the operating parameters of the vehicle; wherein, when the suspension system includes three axes, j=1, 2, 3, and n=14. A control system for a vehicle suspension system, comprising at least one of the following: a first adjusting device configured to perform a first adjustment on a damping parameter of at least one of the plurality of shafts of the suspension system based on road surface information ahead of the vehicle and operating parameters of the vehicle; or a second adjustment device configured to perform a second adjustment on a stiffness parameter of at least one of the plurality of shafts of the suspension system based on the road surface information and the operating condition parameter; In which, the control system also includes a third adjustment device, which is configured to perform a third adjustment on the control force parameters of at least one of the multiple axes of the suspension system based on the vehicle's road excitation information, operating state parameters and a weight matrix corresponding to the operating condition parameters. An electronic device, comprising: at least one processor; and A memory connected to the at least one processor; wherein the memory stores instructions that can be executed by the at least one processor, and the at least one processor implements the control method of the suspension system of the vehicle according to any one of claims 1 to 9 by executing the instructions stored in the memory. A machine-readable storage medium having instructions stored thereon, wherein when the instructions are executed by a processor, the processor is configured to execute the method for controlling a suspension system of a vehicle according to any one of claims 1 to 9. A vehicle comprises the control system of the suspension system according to claim 10.