Suspension damping adaptive control method, controller and computer program product

Abstract

This application relates to the field of vehicle control technology, and provides a suspension damping adaptive control method, controller, and computer program product. The method includes: acquiring suspension state signals during vehicle operation; calculating real-time unsprung mass based on the suspension state signals; determining an unsprung mass compensation coefficient based on the real-time unsprung mass and a preset reference unsprung mass; obtaining a comfort damping force aimed at suppressing vehicle body vibration and a ground contact damping force aimed at suppressing wheel vibration based on the suspension state signals; fusing the comfort damping force and the ground contact damping force according to a weighted coefficient to obtain a fused damping force; dynamically correcting the fused damping force using the unsprung mass compensation coefficient to obtain a target damping force; and outputting the target damping force to the vehicle's adjustable damping shock absorber. This method can correct the damping force output in real time under conditions of changing vehicle unsprung mass, taking into account both vehicle body comfort and wheel ground contact.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, specifically to a suspension damping adaptive control method, controller, and computer program product. Background Technology

[0002] The suspension system is a crucial component of a vehicle's chassis, responsible for transmitting forces and torques between the wheels and the vehicle body, and mitigating impact loads from uneven road surfaces. Its performance significantly impacts ride comfort, handling stability, and braking performance. Unsprung mass refers to the mass of components beneath the suspension system that move with the wheels, typically including the wheels, wheel hubs, brake calipers, steering knuckles, half-shafts, and portions of the suspension arms. During actual vehicle operation, unsprung mass varies within a certain range due to factors such as vehicle load, tire type, and the operating state of the actuators.

[0003] During vehicle operation, both body vibration and wheel vibration exist simultaneously. Body vibration primarily affects ride comfort, while wheel vibration affects the contact between the wheels and the road surface, thus impacting the vehicle's handling stability and braking performance. The frequency range and direction of body vibration and wheel vibration differ.

[0004] Furthermore, when the actual unsprung mass of the vehicle deviates from the preset benchmark value, there is a discrepancy between the suspension damping control output designed based on fixed parameters and the current actual operating conditions of the vehicle, which can easily lead to insufficient suppression of high-frequency wheel vibration and lag in the response of body vibration suppression. Summary of the Invention

[0005] In view of this, embodiments of this application provide a suspension damping adaptive control method, controller, and computer program product to correct the damping force output in real time under the condition of changes in vehicle unsprung mass, taking into account both vehicle comfort and wheel contact.

[0006] A first aspect of this application provides a suspension damping adaptive control method, comprising: Acquire suspension status signals during vehicle operation; Calculate the real-time unsprung mass based on the suspension state signal; The unsprung mass compensation coefficient is determined based on the real-time unsprung mass and the preset reference unsprung mass. Based on the suspension state signal, the comfort damping force aimed at suppressing vehicle body vibration and the ground damping force aimed at suppressing wheel vibration are obtained respectively. The comfort damping force and the ground damping force are combined using a weighted coefficient to obtain the combined damping force; The target damping force is obtained by dynamically correcting the fusion damping force using the unsprung mass compensation coefficient. The target damping force is output to the adjustable damping shock absorber of the vehicle.

[0007] In one embodiment, the suspension state signal includes unsprung vertical acceleration and suspension dynamic travel, and after acquiring the suspension state signal, it further includes: Based on the root mean square value of the unsprung vertical acceleration and the suspension travel, the current road condition level of the vehicle is determined, and the corresponding weighting coefficient is determined based on the road condition level. The road surface condition level includes at least one of good road surface, general road surface and bumpy road surface, and different road surface condition levels correspond to different weighting coefficients.

[0008] In one embodiment, the suspension state signal includes unsprung vertical acceleration and sprung vertical acceleration, and the calculation of real-time unsprung mass based on the suspension state signal includes: The collected suspension state signals are input into a pre-constructed 1 / 4 suspension dynamics model; The real-time unsprung mass is obtained by solving the 1 / 4 suspension dynamics model using a preset state observer.

[0009] In one embodiment, the 1 / 4 suspension dynamics model is: In the formula, Indicates the sprung mass. Indicates unsprung mass. Indicates the suspension spring stiffness. Indicates tire stiffness. Indicates controllable damping force. Indicates the vertical displacement of the spring. Indicates the vertical displacement under the spring. Indicates the vertical acceleration on the spring. Indicates the unsprung vertical acceleration. This indicates road surface excitation.

[0010] In one embodiment, the formula for calculating the unsprung mass compensation coefficient is: In the formula, This represents the unsprung mass compensation coefficient. This indicates the real-time unsprung mass. This represents the preset reference unsprung mass.

[0011] In one embodiment, the formula for calculating the comfort damping force is: The formula for calculating the grounding damping force is as follows: In the formula, This indicates the aforementioned comfort damping force. This indicates the grounding damping force. Indicates the comfort damping coefficient. Indicates the grounding damping coefficient. Indicates the vertical velocity of the vehicle body. This indicates the vertical speed of the wheel.

[0012] In one embodiment, the formula for calculating the fusion damping force is: In the formula, This indicates the fusion damping force. This represents the target damping force. This represents the weighting coefficient.

[0013] In one embodiment, the formula for calculating the target damping force is: In the formula, This represents the unsprung mass compensation coefficient. This indicates the aforementioned comfort damping force. This indicates the grounding damping force.

[0014] A second aspect of this application provides a suspension damping adaptive control system, comprising: The signal acquisition module is used to acquire suspension status signals during vehicle operation; The unsprung mass identification module calculates the equivalent unsprung mass based on the suspension state signal and uses it as the real-time unsprung mass; The compensation coefficient calculation module is used to determine the unsprung mass compensation coefficient based on the real-time unsprung mass and the preset reference unsprung mass. The dual-objective damping force calculation module is used to obtain, based on the suspension state signal, a comfort damping force aimed at suppressing vehicle body vibration and a ground-level damping force aimed at suppressing wheel vibration. The damping force fusion module is used to fuse the comfort damping force and the grounding damping force according to a weighting coefficient to obtain the fused damping force; The damping force correction module is used to dynamically correct the fused damping force using the unsprung mass compensation coefficient to obtain the target damping force, and output it to the adjustable damping shock absorber of the vehicle.

[0015] A third aspect of this application provides a vehicle controller, including a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the controller causes the controller to implement the suspension damping adaptive control method provided in the first aspect of this application.

[0016] A fourth aspect of this application provides a computer program product including a computer program that, when run, causes the method described in the first aspect of this application to be performed.

[0017] The first aspect of this application provides a suspension damping adaptive control method that calculates the real-time unsprung mass using suspension state signals and further calculates the unsprung mass compensation coefficient. It then dynamically corrects the fused damping force obtained by weighted coefficient fusion, enabling the damping force output to adaptively adjust with changes in the vehicle's equivalent unsprung mass. Furthermore, the same damping force output simultaneously includes a comfort damping force aimed at suppressing vehicle body vibration and a ground-based damping force aimed at suppressing wheel vibration, thus balancing vehicle comfort and wheel ground contact.

[0018] It is understood that the beneficial effects of the second to fourth aspects mentioned above can be found in the relevant descriptions in the first aspect mentioned above, and will not be repeated here. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic flowchart of a suspension damping adaptive control method provided in an embodiment of this application; Figure 2 This is a schematic flowchart of a suspension damping adaptive control method provided in another embodiment of this application; Figure 3 This is a schematic diagram of a 1 / 4 suspension dynamics model provided in an embodiment of this application. Detailed Implementation

[0021] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0022] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0023] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0024] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0025] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0026] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0027] The adaptive suspension damping control method provided in this invention can be applied to various vehicles equipped with adjustable damping suspensions, including pure electric vehicles, hybrid electric vehicles, range-extended electric vehicles, fuel cell vehicles, and gasoline vehicles. It adaptively corrects the suspension damping force based on changes in the vehicle's equivalent unsprung mass. Specifically, it can be executed by the vehicle's suspension controller, chassis domain controller, or vehicle controller when running a computer program with corresponding functions. The executing entity is hereinafter referred to as the processor. This invention does not impose any restrictions on the specific type of vehicle.

[0028] like Figure 1 As shown, the adaptive suspension damping control method provided in this embodiment of the invention includes the following steps S101 to S107 executed by a processor: Step S101: Obtain the suspension status signal during vehicle operation.

[0029] In applications, suspension status signals refer to physical quantities used to characterize the motion state of the suspension system itself. Specifically, these signals can be acquired by acceleration sensors located at the vehicle body and wheels, and displacement sensors located at the shock absorbers or suspension arms. After receiving these signals, the processor performs digital sampling, filtering and noise reduction, and time alignment preprocessing to obtain the suspension status signals usable in subsequent steps. The sampling frequency can be set according to actual needs; a higher sampling frequency provides a more detailed characterization of high-frequency vibrations.

[0030] Step S102: Calculate the real-time unsprung mass based on the suspension state signal.

[0031] In applications, real-time unsprung mass, also known as equivalent unsprung mass, is the concentrated mass equivalent to the various components under the suspension system that move with the wheels. Its value varies within a certain range due to factors such as vehicle load, tire specifications, suspension geometry, and the operating state of the actuators. Specifically, it can be obtained by recursively estimating unknown parameters in the system using real-time acquired suspension state signals during vehicle operation. The processor, based on the vehicle's suspension dynamics model, uses the suspension state signals as model input and recursively solves for the equivalent unsprung mass parameters in the model through a preset state observer, outputting the equivalent unsprung mass, i.e., the real-time unsprung mass.

[0032] Step S103: Determine the unsprung mass compensation coefficient based on the real-time unsprung mass and the preset reference unsprung mass.

[0033] In applications, the preset reference unsprung mass refers to the equivalent unsprung mass set at the vehicle's factory calibration, corresponding to the vehicle's standard load and standard configuration, and is usually stored in the processor's non-volatile memory. The unsprung mass compensation coefficient is used to describe the degree of deviation of the real-time unsprung mass from the reference unsprung mass. When the real-time unsprung mass is greater than the reference unsprung mass, the unsprung mass compensation coefficient is greater than 1; when the real-time unsprung mass is equal to the reference unsprung mass, the unsprung mass compensation coefficient is equal to 1; when the real-time unsprung mass is less than the reference unsprung mass, the unsprung mass compensation coefficient is less than 1.

[0034] Step S104: Based on the suspension state signal, obtain the comfort damping force aimed at suppressing vehicle body vibration and the ground damping force aimed at suppressing wheel vibration.

[0035] In application, comfort damping force aims to suppress vehicle body vibration, acting on the vehicle body motion corresponding to the sprung mass. Its effect is reflected in a reduction in the vibration amplitude and intensity perceived by the occupants. Ground contact damping force aims to suppress wheel vibration, acting on the wheel motion corresponding to the unsprung mass. Its effect is reflected in a reduction in the fluctuation of contact pressure between the wheel and the road surface and an improvement in the wheel's ability to follow changes in road geometry. The processor calculates comfort damping force and ground contact damping force separately based on suspension state signals, allowing these two target damping forces to be further combined in subsequent steps.

[0036] Step S105: Combine the comfort damping force and the ground damping force according to the weighting coefficient to obtain the combined damping force.

[0037] In application, the weighting factor is used to describe the proportion of comfort damping force and ground damping force in the combined damping force. The weighting factor can be adjusted according to the actual operating conditions of the vehicle.

[0038] Step S106: Dynamically correct the fusion damping force using the unsprung mass compensation coefficient to obtain the target damping force, and output it to the adjustable damping shock absorber of the vehicle.

[0039] In application, the processor uses the unsprung mass compensation coefficient as a correction factor to dynamically adjust the fused damping force. The fused damping force is multiplied by the unsprung mass compensation coefficient to obtain the target damping force. Since the unsprung mass compensation coefficient changes with the real-time unsprung mass, the target damping force can also be adaptively adjusted synchronously. When the real-time unsprung mass increases, the target damping force is amplified relative to the fused damping force, enhancing the suppression of high-frequency wheel vibrations; when the real-time unsprung mass decreases, the target damping force also decreases, avoiding the impact caused by excessive damping force.

[0040] In applications, adjustable damping shock absorbers refer to shock absorbers whose damping coefficient can be adjusted in real time according to external control signals, such as CDC (Continuously Damping Control) adjustable damping shock absorbers and magnetorheological shock absorbers. The processor converts the target damping force into the control current or voltage required by the adjustable damping shock absorber after amplitude limiting, and outputs it to the solenoid valve coil or magnetorheological valve coil of the adjustable damping shock absorber through the vehicle chassis wiring harness, so that the output of the adjustable damping shock absorber matches the target damping force. The upper and lower limits of the amplitude limiting process are set according to the maximum and minimum damping force output capabilities of the adjustable damping shock absorber.

[0041] In one embodiment, step S101 includes: Collect the sprung vertical acceleration of the vehicle Vertical acceleration under the spring Suspension travel .

[0042] In application, sprung vertical acceleration, i.e., the vertical acceleration of the vehicle body, is collected by an acceleration sensor mounted on the vehicle body (e.g., at the mounting point on top of the shock absorber) and is used to characterize the vertical vibration of the vehicle body. Unsprung vertical acceleration, i.e., the vertical acceleration of the wheel, is collected by an acceleration sensor mounted near the wheel (e.g., on the steering knuckle or wheel hub bracket) and is used to characterize the vertical vibration of the wheel. Suspension travel is collected by a displacement sensor mounted on the shock absorber or suspension arm and reflects the relative displacement change between the vehicle body and the wheel. These three signals collectively reflect the operating state of the suspension system from different dimensions.

[0043] In one embodiment, such as Figure 2 As shown, the adaptive suspension damping control method provided in this embodiment of the invention, after acquiring the suspension state signal, further includes: Based on the root mean square value of the unsprung vertical acceleration and the suspension travel, the current road condition level of the vehicle is determined, and the corresponding weighting coefficient is determined based on the road condition level. The road surface condition level includes at least one of good road surface, general road surface and bumpy road surface, and different road surface condition levels correspond to different weighting coefficients.

[0044] In applications, the root mean square (RMS) value of wheel vertical acceleration refers to the value obtained by squaring, averaging, and then taking the square root of the sampled wheel vertical acceleration values ​​within a preset time window. Its magnitude reflects the overall level of wheel vertical vibration energy. The length of the preset time window can be set according to actual needs. The longer the window, the smoother the response to sudden bumps and the more gradual the response to road surface changes; the shorter the window, the more sensitive the response to road surface changes.

[0045] In application, road condition level identification is based on two indicators: the root mean square (RMS) value of wheel vertical acceleration and suspension travel. When the RMS value of wheel vertical acceleration is low and the suspension travel is small, the processor classifies the current road condition as good. When the RMS value of wheel vertical acceleration is at a moderate level and the suspension travel increases accordingly, the processor classifies the current road condition as normal. When the RMS value of wheel vertical acceleration is high and the suspension travel increases significantly, the processor classifies the current road condition as bumpy. Specific judgment thresholds can be calibrated according to vehicle vehicle characteristics.

[0046] In application, the weighting coefficient is adaptively adjusted according to the road condition level, so that the relative proportions of comfort damping force and ground contact damping force in the combined damping force match the road condition. Under good road conditions, appropriately increasing the weighting coefficient can highlight the role of comfort damping force, giving occupants a smoother ride; under bumpy road conditions, appropriately decreasing the weighting coefficient can highlight the role of ground contact damping force, strengthening the ground contact between the wheels and the road surface.

[0047] By introducing road condition identification and using the identification results to adjust the weighting coefficients, the composition ratio of the fused damping force can be adaptively adjusted according to changes in road conditions, thereby improving the adaptability of the control method to different road conditions.

[0048] In one embodiment, step S102 includes: The collected suspension state signals are input into a pre-constructed 1 / 4 suspension dynamics model; The real-time unsprung mass is obtained by solving the 1 / 4 suspension dynamics model using a preset state observer.

[0049] In applications, the 1 / 4 suspension dynamics model is a mathematical model that simplifies the entire vehicle suspension into a two-degree-of-freedom mass-spring-damper system at a single wheel, used to describe the kinematic relationship between sprung and unsprung masses in the vertical direction. See also Figure 3In the 1 / 4 suspension dynamics model, the sprung mass is connected to the suspension spring and controllable damping, the other end of the suspension spring and controllable damping is connected to the unsprung mass, the unsprung mass is connected to the tire stiffness, and the other end of the tire stiffness is connected to the road excitation input. The vertical displacement of the sprung mass is calculated upwards from the reference point, the vertical displacement of the unsprung mass is calculated upwards from the reference point, and the suspension travel is represented by the difference between the vertical displacement of the sprung mass and the vertical displacement of the unsprung mass.

[0050] In applications, the preset state observer is an algorithm module that estimates the internal state and parameters of the system based on the system dynamics model. Common preset state observers include, but are not limited to, Kalman filters, extended Kalman filters, unscented Kalman filters, Romberg observers, and sliding mode observers. Those skilled in the art can select the appropriate type according to the model characteristics and real-time requirements. The processor takes the vehicle vertical acceleration, wheel vertical acceleration, and suspension dynamic travel from the suspension state signal as input to the 1 / 4 suspension dynamics model, and uses the preset state observer to recursively estimate the equivalent unsprung mass parameters in the model to obtain the real-time unsprung mass.

[0051] By using a 1 / 4 suspension dynamics model as the basis for identification and recursively solving the problem through a pre-set state observer, the identification results are given physical meaning by inheriting the suspension mechanical relationships expressed by the model. On the other hand, the state observer is used to filter measurement noise, so that the identification results remain stable during the actual operation of the vehicle.

[0052] In one embodiment, the 1 / 4 suspension dynamics model is: In the formula, Indicates the sprung mass. Indicates unsprung mass. Indicates the suspension spring stiffness. Indicates tire stiffness. Indicates controllable damping force. Indicates the vertical displacement of the spring. Indicates the vertical displacement under the spring. Indicates the vertical acceleration on the spring. Indicates the unsprung vertical acceleration. This indicates road surface excitation.

[0053] In application, the 1 / 4 suspension dynamics model reflects the calculated relationship between the above parameters, thus allowing the unknown quantity (i.e., real-time sprung mass) to be inferred from the known quantities in the model. In this model, sprung mass, suspension spring stiffness, and tire stiffness are known parameters of the suspension system, whose values ​​can be obtained through factory calibration. The controllable damping force is the damping force previously output by the processor and can be stored within the processor itself. Sprung vertical displacement, unsprung vertical displacement, and suspension travel are obtained from displacement sensors at the shock absorbers or suspension arms. Sprung vertical acceleration and unsprung vertical acceleration are collected by acceleration sensors at the vehicle body and wheels. Road excitation can be treated as an unknown disturbance term during the recursive process of the preset state observer. Based on the above known and measurable quantities, the unknown parameter in the 1 / 4 suspension dynamics model is the unsprung mass. The preset state observer obtains an estimate of the real-time unsprung mass by minimizing the residual between the model output and the actual measurement.

[0054] By clarifying the specific form of the 1 / 4 suspension dynamics model, the mechanistic relationship on which the equivalent unsprung mass identification is based is fixed, which facilitates recursive solution through numerical methods and is beneficial to engineering implementation.

[0055] In one embodiment, the formula for calculating the unsprung mass compensation coefficient is: In the formula, This represents the unsprung mass compensation coefficient. This indicates the real-time unsprung mass. The preset reference unsprung mass is used to indicate the unsprung mass. When the real-time unsprung mass is greater than the preset reference unsprung mass, the unsprung mass compensation coefficient is greater than 1.

[0056] In applications where the vehicle is loaded with many passengers or cargo, uses heavier tires, or has accumulated a lot of wear dust in the braking system, the real-time unsprung mass is greater than the reference unsprung mass, and the unsprung mass compensation coefficient is greater than 1. In this case, the unsprung mass compensation coefficient is used to dynamically correct the fusion damping force, which amplifies the target damping force compared to the fusion damping force, thus strengthening the suppression of high-frequency wheel vibrations. Conversely, when the vehicle is unloaded or lighter tires are replaced, the real-time unsprung mass is less than the reference unsprung mass, and the unsprung mass compensation coefficient is less than 1. In this case, the target damping force is reduced compared to the fusion damping force, preventing excessive damping force from causing impacts.

[0057] By defining the unsprung mass compensation coefficient as the ratio of real-time unsprung mass to reference unsprung mass, the unsprung mass compensation coefficient has a direct physical meaning, which can quantitatively reflect the degree of deviation of the vehicle's current actual unsprung mass from the design reference, and facilitates its combination with the fusion damping force in a product relationship.

[0058] In one embodiment, the formula for calculating the comfort damping force is: The formula for calculating the grounding damping force is as follows: In the formula, This indicates the aforementioned comfort damping force. This indicates the grounding damping force. Indicates the comfort damping coefficient. Indicates the grounding damping coefficient. Indicates the vertical velocity of the spring. This indicates the unsprung vertical velocity.

[0059] In application, the comfort damping force is expressed as the product of the comfort damping coefficient and the difference between the sprung vertical velocity and the unsprung vertical velocity. The difference between the sprung vertical velocity and the unsprung vertical velocity corresponds to the suspension operating speed. The direction of the comfort damping force is opposite to the direction of the suspension operating speed and is used to suppress the vibration of the vehicle body relative to the wheels. The ground damping force is expressed as the product of the ground damping coefficient and the unsprung vertical velocity. The direction of the ground damping force is opposite to the direction of the unsprung vertical velocity and is used to suppress the vibration of the wheels themselves relative to the ground.

[0060] In application, the sprung vertical velocity can be obtained by integrating the sprung vertical acceleration over time, and the unsprung vertical velocity can be obtained by integrating the unsprung vertical acceleration over time. The comfort damping coefficient and the ground damping coefficient are pre-calibrated control parameters. During calibration, the target frequency range corresponding to the comfort damping coefficient covers the frequency range near the natural frequency of the vehicle body, and the target frequency range corresponding to the ground damping coefficient covers the frequency range near the natural frequency of the wheel, so that the two damping forces have a targeted suppression effect on vehicle body vibration and wheel vibration, respectively.

[0061] By decoupling the comfort damping force and the ground damping force according to the above formula, the two damping forces can be quantified independently for vehicle body vibration and wheel vibration, providing a quantitative basis for subsequent fusion by weighting coefficient.

[0062] In one embodiment, the formula for calculating the fusion damping force is: In the formula, This indicates the fusion damping force. This represents the target damping force. This represents the weighting coefficient.

[0063] In one embodiment, the formula for calculating the target damping force is: In the formula, This represents the unsprung mass compensation coefficient. This indicates the aforementioned comfort damping force. This indicates the grounding damping force.

[0064] In application, the weighting coefficients range from 0 to 1. Specific values ​​can be determined based on road condition level and vehicle speed using pre-calibrated functions, lookup tables, or fuzzy rules. When using a lookup table, the two-dimensional lookup table uses road condition level and vehicle speed as input. Under good road conditions and low vehicle speeds, the weighting coefficients output from the lookup table tend to be larger, with comfort-oriented damping force dominating the integrated damping force. Under bumpy road conditions or high vehicle speeds, the weighting coefficients output from the lookup table tend to be smaller, with ground-level damping force dominating the integrated damping force.

[0065] In application, the fusion damping force is obtained by adding the product of the weighting coefficient and the comfort damping force, and the product of the complementary amount of the weighting coefficient (i.e., 1 minus the difference of the weighting coefficients) and the grounding damping force. The two parts are complementary. The target damping force is obtained by multiplying the unsprung mass compensation coefficient and the fusion damping force. The fusion damping force is output to the adjustable damping shock absorber after being corrected by the unsprung mass compensation coefficient.

[0066] By adjusting the composition ratio of the fusion damping force with a weighting coefficient and adjusting the overall value of the fusion damping force with an unsprung mass compensation coefficient, the target damping force simultaneously reflects the adjustment effect of the weighting coefficient at the composition ratio level and the adjustment effect of the unsprung mass compensation coefficient at the overall value level. The two adjustment effects are independent of each other and superimposed on each other, so that the target damping force can adapt to different road conditions and vehicle speeds, as well as different equivalent unsprung masses.

[0067] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0068] This invention also provides a suspension damping adaptive control system, comprising: The signal acquisition module is used to acquire suspension status signals during vehicle operation; The unsprung mass identification module calculates the equivalent unsprung mass based on the suspension state signal and uses it as the real-time unsprung mass; The compensation coefficient calculation module is used to determine the unsprung mass compensation coefficient based on the real-time unsprung mass and the preset reference unsprung mass. The dual-objective damping force calculation module is used to obtain, based on the suspension state signal, a comfort damping force aimed at suppressing vehicle body vibration and a ground-level damping force aimed at suppressing wheel vibration. The damping force fusion module is used to fuse the comfort damping force and the grounding damping force according to a weighting coefficient to obtain the fused damping force; The damping force correction module is used to dynamically correct the fused damping force using the unsprung mass compensation coefficient to obtain the target damping force. A damping force output module is used to output the target damping force to the adjustable damping shock absorber of the vehicle.

[0069] This invention also provides a vehicle including the aforementioned adaptive suspension damping control system. The vehicle can be any one of a pure electric vehicle, a hybrid electric vehicle, a range-extended electric vehicle, a fuel cell vehicle, or a gasoline-powered vehicle.

[0070] In application, the vehicle also includes an adjustable damping shock absorber that works in conjunction with the adaptive suspension damping control system. This adjustable damping shock absorber includes, but is not limited to, at least one of a CDC adjustable damping shock absorber and a magnetorheological damping shock absorber. The CDC adjustable damping shock absorber adjusts the damping coefficient by changing the flow area of ​​the damping fluid through variations in the opening of an internal solenoid valve. The magnetorheological damping shock absorber adjusts the damping coefficient by applying a magnetic field to the magnetorheological fluid, thereby changing the apparent viscosity of the magnetorheological fluid. The adaptive suspension damping control system converts the target damping force into a corresponding control current or control voltage, outputting it to the solenoid valve coil or magnetorheological valve coil of the adjustable damping shock absorber, thus matching the actual damping force of the adjustable damping shock absorber with the target damping force.

[0071] It should be noted that the information interaction and execution process between the above system and the vehicle are based on the same concept as the method embodiment of the present invention. For details on its specific functions and the resulting technical effects, please refer to the method embodiment section, which will not be repeated here.

[0072] This application also provides a vehicle controller, including a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the controller implements the suspension damping adaptive control method as provided in the first aspect of this application.

[0073] This application also provides a computer program product, including a computer program that, when run, causes the method described in the first aspect of this application to be executed.

[0074] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for adaptive control of suspension damping, characterized in that, include: Acquire suspension status signals during vehicle operation; Calculate the real-time unsprung mass based on the suspension state signal; The unsprung mass compensation coefficient is determined based on the real-time unsprung mass and the preset reference unsprung mass. Based on the suspension state signal, the comfort damping force aimed at suppressing vehicle body vibration and the ground damping force aimed at suppressing wheel vibration are obtained respectively. The comfort damping force and the ground damping force are combined using a weighted coefficient to obtain the combined damping force; The unsprung mass compensation coefficient is used to dynamically correct the fusion damping force to obtain the target damping force, which is then output to the adjustable damping shock absorber of the vehicle.

2. The adaptive suspension damping control method according to claim 1, characterized in that, The suspension status signal includes unsprung vertical acceleration and suspension dynamic travel. After acquiring the suspension status signal, it also includes: Based on the root mean square value of the unsprung vertical acceleration and the suspension travel, the current road condition level of the vehicle is determined, and the corresponding weighting coefficient is determined based on the road condition level. The road surface condition level includes at least one of good road surface, general road surface and bumpy road surface, and different road surface condition levels correspond to different weighting coefficients.

3. The adaptive suspension damping control method according to claim 1, characterized in that, The suspension state signal includes unsprung vertical acceleration and sprung vertical acceleration. The calculation of real-time unsprung mass based on the suspension state signal includes: The collected suspension state signals are input into a pre-constructed 1 / 4 suspension dynamics model; The real-time unsprung mass is obtained by solving the 1 / 4 suspension dynamics model using a preset state observer.

4. The adaptive suspension damping control method according to claim 3, characterized in that, The 1 / 4 suspension dynamics model is as follows: In the formula, Indicates the sprung mass. Indicates unsprung mass. Indicates the suspension spring stiffness. Indicates tire stiffness. Indicates controllable damping force. Indicates the vertical displacement of the spring. Indicates the vertical displacement under the spring. Indicates the vertical acceleration on the spring. Indicates the unsprung vertical acceleration. This indicates road surface excitation.

5. The adaptive control method for suspension damping according to claim 1, characterized in that, The formula for calculating the unsprung mass compensation coefficient is as follows: In the formula, This represents the unsprung mass compensation coefficient. This indicates the real-time unsprung mass. This represents the preset reference unsprung mass.

6. The adaptive control method for suspension damping according to claim 1, characterized in that, The formula for calculating the comfort damping force is as follows: The formula for calculating the grounding damping force is as follows: In the formula, This indicates the aforementioned comfort damping force. This indicates the grounding damping force. Indicates the comfort damping coefficient. Indicates the grounding damping coefficient. Indicates the vertical velocity of the vehicle body. This indicates the vertical speed of the wheel.

7. The adaptive suspension damping control method according to claim 2, characterized in that: The formula for calculating the fusion damping force is: In the formula, This indicates the fusion damping force. This represents the target damping force. This represents the weighting coefficient.

8. The adaptive control method for suspension damping according to claim 2, characterized in that: The formula for calculating the target damping force is: In the formula, This represents the unsprung mass compensation coefficient. This indicates the aforementioned comfort damping force. This indicates the grounding damping force.

9. A vehicle controller, characterized in that, The system includes a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, it causes the controller to implement the method as described in any one of claims 1 to 8.

10. A computer program product, characterized in that, Includes a computer program, which, when run, causes the method described in any one of claims 1 to 8 to be performed.

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