Semi-active suspension control method, device and equipment and storage medium

Abstract

The invention discloses a control method, device and equipment of a semi-active suspension and a storage medium, and relates to the technical field of vehicle engineering.The control method of the semi-active suspension comprises the steps that under the condition that a vehicle-mounted system does not have a fault, driving modes are distinguished according to a mode selection signal, and a current driving mode is obtained; when the current driving mode is not the deceleration strip mode, determining a target control strategy according to the current driving mode; and controlling the semi-active suspension according to the target control strategy. The vehicle suspension system can be adjusted according to different driving requirements and road conditions, more excellent driving feeling and safety are provided, a driver can switch between a comfortable driving mode and a motion driving mode through an accurate control strategy, meanwhile, better vehicle stability and control performance are obtained under different road conditions, and the driving experience of the driver is improved. The smoothness of the vehicle and the road adhesiveness are improved, and the overall driving comfort and safety are improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle engineering technology, and in particular to a control method, device, equipment and storage medium for a semi-active suspension. Background Art

[0002] In modern automotive engineering, vehicle ride comfort and road adhesion are important indicators of driving comfort and safety. Traditional suspension systems have limitations in improving these aspects, so more advanced control methods are needed to optimize these characteristics.

[0003] At present, passive suspension and active suspension are common technical routes. Passive suspension cannot dynamically adjust damping, and although active suspension can adjust damping in real time to adapt to different road conditions, its structure is complex and costly. Semi-active suspension is a compromise solution that combines the advantages of passive and active suspensions and can balance ride comfort and handling stability to a certain extent.

[0004] However, the current semi-active suspension system still faces some challenges. In particular, in the low-frequency resonance area, the dynamic deformation of the vehicle's tires increases, resulting in deterioration of road adhesion; at the same time, in terms of driving smoothness, the performance of the low-frequency resonance area is not satisfactory. In addition, the existing control algorithm is not accurate enough in the division of different driving modes, which limits the optimal performance of the suspension system under different working conditions. Therefore, how to improve the vehicle's smoothness and road adhesion has become an urgent problem to be solved.

[0005] The above contents are only used to assist in understanding the technical solution of the present application and do not constitute an admission that the above contents are prior art. Summary of the invention

[0006] The purpose of this application is to provide a control method, device, equipment and storage medium for a semi-active suspension, aiming to solve the technical problem of how to improve the smoothness and road adhesion of a vehicle.

[0007] To achieve the above objectives, the present application proposes a control method for a semi-active suspension, the method comprising:

[0008] When there is no fault in the vehicle system, the driving mode is distinguished according to the mode selection signal to obtain the current driving mode;

[0009] When the current driving mode is not a speed bump mode, determining a target control strategy according to the current driving mode;

[0010] The semi-active suspension is controlled according to the target control strategy.

[0011] In one embodiment, the step of controlling the semi-active suspension according to the target control strategy includes:

[0012] When the target control strategy is a ceiling-acceleration hybrid damping control strategy, obtaining ceiling sensor data, wherein the ceiling sensor data includes a height change of a vehicle body;

[0013] Calculating a road surface excitation value according to the acceleration sensor data;

[0014] Get the frequency band of the current road;

[0015] The damping characteristic in the semi-active suspension is linearly adjusted according to the vehicle height change, the road excitation value, the frequency band and a first preset linear control strategy.

[0016] In one embodiment, the step of controlling the semi-active suspension according to the target control strategy includes:

[0017] When the target control strategy is a ground-shed linear semi-active control strategy, acquiring ground-shed sensor data, wherein the ground-shed sensor data includes a vehicle chassis motion state and a road surface unevenness;

[0018] The damping characteristics and wheel braking force in the semi-active suspension are linearly adjusted according to the vehicle chassis motion state, the road surface unevenness and a second preset linear control strategy.

[0019] In one embodiment, the step of controlling the semi-active suspension according to the target control strategy includes:

[0020] When the target control strategy is a ceiling-ground ceiling hybrid control strategy, obtaining a motor angular acceleration and a steering wheel angle;

[0021] When the motor angular acceleration is greater than a preset angular acceleration threshold, the adjustment coefficient of the proportion of the ceiling and floor strategies is adjusted to a preset adjustment coefficient value;

[0022] When the motor angular acceleration is less than or equal to the preset angular acceleration threshold and the steering wheel angle is greater than the preset angle threshold, adjusting the adjustment coefficient of the steering wheel angle in a normal distribution form;

[0023] When the motor angular acceleration is less than or equal to the preset angular acceleration threshold and the steering wheel angle is less than or equal to the preset angle threshold, adjusting the adjustment coefficient to a preset balance coefficient;

[0024] The semi-active suspension is controlled according to the adjustment coefficient, the floor-hook linear semi-active control strategy and the sky-hook-acceleration hybrid damping control strategy.

[0025] In one embodiment, after the step of distinguishing the driving modes according to the mode selection signal to obtain the current driving mode, the method further includes:

[0026] When the current driving mode is a speed bump mode, the spring load is controlled by a smoothness mode strategy;

[0027] Acquiring the current vehicle speed, and calculating the time to maintain the speed reduction mode according to the current vehicle speed;

[0028] If it is detected again that the vehicle passes through the speed bump within the time, the process returns to the step of obtaining the current vehicle speed and calculating the time to maintain the speed bump mode according to the current vehicle speed.

[0029] In one embodiment, when the current driving mode is the speed bump mode, before the step of controlling the sprung load by the smoothness mode strategy, the method further includes:

[0030] Filtering the acceleration sensor data to obtain filtered data, wherein the filtered data includes wheel acceleration and suspension travel;

[0031] determining a wheel center vertical acceleration according to the wheel acceleration;

[0032] When the wheel center vertical acceleration and the suspension dynamic travel are both greater than or equal to a preset threshold, determining that the current driving mode is a speed bump mode;

[0033] When the wheel center vertical acceleration or the suspension dynamic stroke is less than the preset threshold, it is determined that the current driving mode is not a speed bump mode.

[0034] In one embodiment, when there is no fault in the vehicle system, before the step of distinguishing the driving mode according to the mode selection signal to obtain the current driving mode, the step further includes:

[0035] Determining a fault condition of the vehicle-mounted system based on acceleration sensor data and controller area network communication data;

[0036] When the vehicle-mounted system fails, the driving mode is switched to a passive vibration reduction mode.

[0037] In addition, to achieve the above-mentioned purpose, the present application also proposes a control device for a semi-active suspension, the device comprising:

[0038] A mode distinguishing module is used to distinguish the driving mode according to the mode selection signal to obtain the current driving mode when there is no fault in the vehicle system;

[0039] A strategy selection module, configured to determine a target control strategy according to the current driving mode when the current driving mode is not a speed bump mode;

[0040] A control module is used to control the semi-active suspension according to the target control strategy.

[0041] In addition, to achieve the above-mentioned purpose, the present application also proposes a control device for a semi-active suspension, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the control method for the semi-active suspension as described above.

[0042] In addition, to achieve the above-mentioned purpose, the present application also proposes a storage medium, which is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the control method of the semi-active suspension as described above are implemented.

[0043] One or more technical solutions proposed in this application have at least the following technical effects:

[0044] In the present application, when there is no fault in the vehicle system, the driving mode is distinguished according to the mode selection signal to obtain the current driving mode; when the current driving mode is not the speed bump mode, the target control strategy is determined according to the current driving mode; and the semi-active suspension is controlled according to the target control strategy. The present application first distinguishes the driving mode according to the mode selection signal, which means that the system determines the current driving mode according to the received signal, which may include comfort mode, sports mode, adaptive mode, etc. These modes will affect the working mode of the vehicle suspension and transmission system. When it is determined that the current driving mode is not the speed bump mode, the system will select the corresponding target control strategy according to the current driving mode. For example, the comfort mode may give priority to providing a smooth driving experience, the sports mode may emphasize power output and suspension rigidity, and the adaptive mode will automatically adjust according to the real-time driving conditions and road conditions to balance comfort and performance. Finally, according to the determined target control strategy, the system accurately controls the semi-active suspension. This includes adjusting the damping characteristics of the suspension, wheel braking force and other parameters according to the strategy to ensure that the suspension system can provide the best suspension performance and driving experience in different driving modes. This application can adjust the vehicle suspension system according to different driving needs and road conditions, providing a better driving experience and safety. Through precise control strategies, the driver can switch between comfort and sport driving modes, while obtaining better vehicle stability and handling performance under different road conditions, improving the vehicle's smoothness and road adhesion, and improving overall driving comfort and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0046] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0047] Figure 1 A schematic diagram of a flow chart provided for the first embodiment of the control method of the semi-active suspension of the present application;

[0048] Figure 2 A schematic diagram of a flow chart of adjusting the adjustment coefficient in an adaptive mode provided in Embodiment 1 of the control method for a semi-active suspension of the present application;

[0049] Figure 3 A schematic diagram of the normal distribution relationship between the steering wheel angle and the adjustment coefficient provided in Example 1 of the control method for the semi-active suspension of the present application;

[0050] Figure 4 A schematic diagram of a flow chart provided for the second embodiment of the control method of the semi-active suspension of the present application;

[0051] Figure 5 A schematic diagram of the frequency response characteristics of the SH-ADD control strategy provided in Embodiment 2 of the control method for the semi-active suspension of the present application;

[0052] Figure 6 A schematic diagram of a brief flow chart of a control method for a semi-active suspension provided in Embodiment 2 of the present application;

[0053] Figure 7 This is a schematic diagram of the module structure of the control device of the semi-active suspension according to an embodiment of the present application;

[0054] Figure 8 Schematic diagram of the device structure of the hardware operating environment involved in the control method of the semi-active suspension in the embodiment of the present application.

[0055] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0056] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0057] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0058] In modern automotive engineering, vehicle ride comfort and road adhesion are key indicators of driving comfort and safety. Traditional suspension systems are limited by their insufficient ability to adjust damping, so more advanced control methods are needed to optimize these characteristics. Passive suspension cannot dynamically adjust damping. Although active suspension can adjust damping in real time to adapt to different road conditions, its complex structure and high cost limit its widespread application. Semi-active suspension, as a compromise, combines the advantages of passive and active suspensions and can balance ride comfort and handling stability to a certain extent. However, existing semi-active suspension systems still face challenges, especially in the low-frequency resonance area, where increased tire dynamic deformation leads to deteriorated road adhesion, while low-frequency resonance has a significant impact on ride smoothness. In addition, the existing control algorithm lacks accuracy in dividing different driving modes, which limits the optimal performance of the suspension system under different working conditions.

[0059] The main solution of the embodiment of the present application is: first, the driving mode is distinguished according to the received mode selection signal, which may include comfort mode, sports mode and adaptive mode, etc. These modes will directly affect the vehicle's suspension and transmission system operation mode. When it is confirmed that the current driving mode is not the speed bump mode, the system will select the corresponding target control strategy according to the specific driving mode. For example, the comfort mode focuses on providing a smooth driving experience, the sports mode emphasizes power output and suspension rigidity, and the adaptive mode automatically adjusts according to real-time driving conditions and road conditions to balance comfort and performance requirements. Finally, the system accurately controls the semi-active suspension according to the determined target control strategy, adjusts the suspension's damping characteristics, wheel braking force and other parameters, and ensures the best suspension performance and driving experience in various driving modes.

[0060] It should be noted that the execution subject of the embodiment of the present application may be a computing service device with data processing, network communication and program running functions, such as a tablet computer, a personal computer, a mobile phone, etc., or an electronic device capable of realizing the above functions, a control system of a semi-active suspension system, etc. The control system of a semi-active suspension system is taken as an example to illustrate this embodiment and the following embodiments.

[0061] Based on this, the present application embodiment provides a control method for a semi-active suspension, referring to Figure 1 , Figure 1 This is a flow chart of a first embodiment of a control method for a semi-active suspension of the present application.

[0062] In this embodiment, the control method of the semi-active suspension includes steps S10 to S30:

[0063] Step S10, when there is no fault in the vehicle system, distinguish the driving mode according to the mode selection signal to obtain the current driving mode;

[0064] It should be noted that the vehicle-mounted system refers to the electronic control system or computer system on the entire vehicle, including but not limited to the engine control unit, transmission control unit, suspension control unit, body control unit, etc. These systems collect information through sensors and control various functions and performances of the vehicle through actuators. The mode selection signal is a signal generated by the vehicle system or the driver's operation to indicate or select a specific driving mode. For example, it can be a signal automatically selected by the vehicle system according to road conditions, speed and other conditions, or it can be a signal manually selected by the driver, such as through a button or switch on the dashboard. The driving mode refers to a set of preset parameter configurations that can be adjusted under different operating conditions to optimize the vehicle's performance and driving experience. These configurations can affect engine output, gearbox shifting logic, suspension hardness, power distribution, etc. Common driving modes include speed bump mode, comfort mode, sports mode and adaptive mode, etc. The performance and driving characteristics of the vehicle will be different in different modes. The current driving mode refers to the specific driving mode in which the vehicle is currently in actual operation, that is, the mode actually executed, which can be judged by the mode selection signal of the knob or screen.

[0065] It is understandable that when the vehicle system operates normally, the system first receives data from different sensors, including but not limited to vehicle speed, steering angle, road conditions, etc. These data are transmitted to the control unit, which determines the currently applicable driving mode based on the preset algorithm and logic, combined with the mode selection signal or knob selected by the driver or the system. These driving modes may include speed bump mode, comfort mode, sports mode or adaptive mode, etc. Each mode presets a specific vehicle parameter configuration, such as suspension stiffness, engine output, transmission shift strategy, etc., to optimize driving comfort, stability or performance. Therefore, based on the mode selection signal, the vehicle system can confirm the current driving mode.

[0066] As an example, after the step of distinguishing the driving mode according to the mode selection signal and obtaining the current driving mode, it also includes: when the current driving mode is the speed bump mode, controlling the spring through the smoothness mode strategy; obtaining the current vehicle speed, and calculating the time to maintain the speed bump mode according to the current vehicle speed; when the vehicle is detected passing through the speed bump again within the time, returning to the step of obtaining the current vehicle speed, and calculating the time to maintain the speed bump mode according to the current vehicle speed.

[0067] Speed ​​bump mode refers to a specific driving mode, the main purpose of which is to provide the best ride quality and driving comfort when the vehicle passes over speed bumps. The ride quality mode strategy is an algorithm or control logic that aims to adjust the vehicle's suspension or other related systems according to the current driving mode (such as speed bump mode), vehicle speed and other environmental factors to minimize the bumps and vibrations when the vehicle passes over speed bumps. In the automobile suspension system, spring up refers to the part of the vehicle body above the suspension spring or shock absorber, including the vehicle body, passengers and their loads, etc. This part of the mass moves up and down with the compression and extension of the suspension spring. Its main function is to support the vehicle body, buffer the impact of the road surface and keep the wheels in contact with the ground, thereby ensuring the vehicle's driving stability and ride comfort. Correspondingly, spring down refers to the part below the elastic element, such as wheels, tires and brake systems, which also move up and down relatively with the movement of the suspension, but have a smaller mass than the springs. The current vehicle speed refers to the actual speed of the vehicle at a specific point in time, which is usually provided by the vehicle's sensors or speed calculation system. The time for maintaining the speed bump mode refers to the time period calculated by the system based on the current vehicle speed, that is, the vehicle is maintained in the speed bump mode during this time period to ensure the best effect and driving comfort when passing through the speed bump. In this embodiment, the time for maintaining the speed bump mode is equal to the distance divided by the vehicle speed, and the distance is the distance from the front wheels passing to the distance from the vehicle body completely passing, that is, the length of the vehicle.

[0068] When the current driving mode is detected as speed bump mode, the vehicle suspension system is adjusted through a specific smoothness mode strategy, focusing on controlling the upper part of the suspension (i.e., "on the spring") to reduce the bumpy feeling when passing through the speed bump and improve ride comfort. The system will obtain the current vehicle speed and dynamically calculate the time to maintain the speed bump mode based on the vehicle speed to ensure that the suspension adjustment effect can be effectively maintained at high or low speeds. If the vehicle is detected passing through the speed bump again within the set time, the system will re-obtain the current vehicle speed and adjust the time to continue to maintain the speed bump mode to achieve the best suspension response and driving comfort.

[0069] As an example, when the current driving mode is the speed bump mode, before the step of controlling the spring through the smoothness mode strategy, it also includes: filtering the acceleration sensor data to obtain filtered data, the filtered data including the wheel acceleration and the suspension travel; determining the wheel center vertical acceleration according to the wheel acceleration; when the wheel center vertical acceleration and the suspension travel are both greater than or equal to a preset threshold, determining that the current driving mode is the speed bump mode; when the wheel center vertical acceleration or the suspension travel is less than the preset threshold, determining that the current driving mode is not the speed bump mode.

[0070] Acceleration sensor data refers to the data measured by the sensor installed on the vehicle, which is used to detect the motion state of the wheel and suspension system, including information such as the vertical acceleration of the vehicle body and the acceleration of the wheel. Filtering refers to signal processing of the acceleration sensor data to remove noise or unnecessary high-frequency components to obtain smooth data. In this embodiment, a second-order Butterworth filter is used. Filtered data refers to the acceleration sensor data obtained after processing by the second-order Butterworth filter, including information about the filtered wheel acceleration and suspension dynamic stroke. Wheel acceleration refers to the acceleration at the center of the wheel, which reflects the acceleration change of the wheel in the vertical direction. The suspension dynamic stroke is the result of calculus calculation based on the acceleration sensor data, which is used to measure the motion stroke of the suspension system in the vertical direction, that is, the degree of compression or extension of the suspension spring under force. The vertical acceleration of the wheel center refers to the acceleration at the center of the wheel in the vertical direction, which is calculated by the wheel acceleration data and is used to evaluate the vertical dynamic response of the vehicle when passing through the speed bump. The preset threshold is a pre-set value used to determine whether the vehicle is currently in speed bump mode. It is usually set based on vehicle design and road conditions to distinguish between general driving conditions and specific driving modes, such as speed bump mode.

[0071] First, the data obtained by the acceleration sensor installed on the vehicle is filtered using a second-order Butterworth filter to obtain smooth filtered data, including wheel acceleration. Next, the wheel center vertical acceleration is calculated based on the filtered wheel acceleration, which reflects the change of the wheel in the vertical direction. Subsequently, the acceleration sensor data is used for calculus calculation to derive the dynamic travel information of the suspension system. After calculating the wheel center vertical acceleration and suspension dynamic travel, the system will make a judgment based on the preset threshold: if the wheel center vertical acceleration and suspension dynamic travel are both greater than or equal to the preset threshold, the current driving mode is determined to be the speed bump mode; if either of them is less than the preset threshold, the current driving mode is determined not to be the speed bump mode. The purpose of these steps is to accurately determine whether the vehicle has passed through a speed bump through filtering and precise data analysis, so as to activate the corresponding smoothness mode strategy to optimize driving comfort and suspension performance.

[0072] As an example, when there is no fault in the vehicle system, the driving mode is distinguished according to the mode selection signal, and before the step of obtaining the current driving mode, it also includes: judging the fault condition of the vehicle system according to the acceleration sensor data and the controller local area network communication data; when there is a fault in the vehicle system, switching the driving mode to the passive vibration reduction mode.

[0073] Controller area network communication data refers to the data communication between controllers on the vehicle through the local area network, including data such as steering wheel angle, power system speed and brake pedal travel. These data may include information from different systems or sensors, such as data sent by the engine control unit, brake system control unit, etc. Fault conditions refer to any one or more components in the vehicle system that have a functional abnormality or fault state. These faults can be detected and diagnosed through the monitoring of acceleration sensor data and controller area network communication data. Once a fault is detected in the vehicle system, the system will automatically switch the current driving mode to the passive vibration reduction mode. Passive vibration reduction mode refers to a suspension working mode, which is characterized by the inability to dynamically adjust the damping force according to road conditions, but a fixed damping characteristic. When a fault occurs in the vehicle system, in order to ensure basic suspension functions and safety, the system will switch the suspension working mode to this passive mode to avoid using complex dynamic adjustment functions.

[0074] First, the vehicle system is judged whether there is a fault by monitoring the acceleration sensor data and the controller area network communication data. The acceleration sensor data is used to detect the acceleration change of the vehicle, while the controller area network communication data is used to obtain the status information and fault codes from each controller. If the system detects that there is no fault in the vehicle system, the driving mode is distinguished according to the preset mode selection signal to determine the current driving mode. These driving modes may include speed bump mode, comfort mode, sports mode and adaptive mode. However, if a fault is detected in the vehicle system, the system will automatically switch the current driving mode to the passive vibration reduction mode. The passive vibration reduction mode is a suspension working mode with fixed damping characteristics, which does not have dynamic adjustment capabilities and is mainly used to ensure basic suspension functions and driving safety. This embodiment ensures the best driving mode selection during normal operation through real-time monitoring and fault judgment mechanisms, and can safely and effectively switch to the appropriate passive vibration reduction mode when the system fails to ensure driving comfort and safety.

[0075] Step S20, when the current driving mode is not a speed bump mode, determining a target control strategy according to the current driving mode;

[0076] It should be noted that the target control strategy refers to the specific control strategy or algorithm selected by the system based on the current driving mode (when it is not the speed bump mode) to achieve the desired driving performance and experience.

[0077] It is understandable that in addition to the speed bump mode, other driving modes include comfort mode, sport mode and adaptive mode. The comfort mode is designed to provide a smooth and comfortable driving experience. The system usually adjusts the suspension and transmission system to reduce the vibration and discomfort of the vehicle on bumpy roads. The corresponding control strategy is the skyhook-control Acceleration Driven Damper (SH-ADD), which combines the vertical movement of the vehicle body (skyhook) and acceleration sensor data to adjust the damping force to optimize comfort. The sport mode is used to provide more aggressive acceleration and cornering performance. The system will increase engine output and adjust the gearbox's shifting logic to achieve a more flexible and dynamic driving experience. The corresponding control strategy is the ground shelf linear semi-active control strategy, which mainly relies on the motion response of the ground shelf (the part where the wheel contacts the road) to adjust the suspension system to provide higher handling performance and driving responsiveness. The adaptive mode automatically adjusts according to the real-time driving conditions and road conditions to balance comfort and performance requirements. The control strategy in this mode is a ceiling-floor hybrid control strategy, which comprehensively considers the dynamic characteristics of the ceiling and floor, dynamically adjusts the suspension damping, and enables the vehicle to automatically adjust in different driving scenarios to maintain the best ride quality and handling performance. Therefore, the target control strategy selects the corresponding control algorithm or strategy according to different driving modes to ensure that the vehicle can provide the best performance and ride experience under various driving conditions.

[0078] Ideal ceiling control: An "ideal ceiling damper" with large damping is installed between the vehicle body and the ideal ceiling to reduce the vertical acceleration on the sprung spring, thereby improving the vehicle's driving smoothness. The motion differential equation of the suspension system of this control strategy is:

[0079]

[0080] Among them, m s Indicates the mass of the vehicle, usually refers to the mass of the vehicle body; c s Represents the damping coefficient in the suspension system. The damping force of the damper is proportional to the speed. Here c s It is this proportionality coefficient; s represents the vertical displacement of the vehicle body, that is, the vertical distance of the vehicle body relative to its static position; Indicates the vertical displacement of the tire, that is, the vertical distance of the tire relative to the ground; k s represents the spring stiffness of the suspension system, that is, the spring force is proportional to the displacement, where k s It is this proportionality factor; It represents the spring displacement of the suspension system, that is, the compression or extension distance of the spring relative to its natural length; F IdSHIt is an idealized damping force used to simulate the damping effect between the vehicle body and a fixed reference point (such as an "ideal ceiling"); Represents the mass of the tire; k t is another damping coefficient and is related to the vertical movement of the tire.

[0081] Ceiling linear semi-active control: The adjustable damper is installed in the suspension system to provide a continuously variable damping force and generate a reverse force on the wheels to achieve the control effect of the suspension. The motion differential equation of the suspension system of this control strategy is:

[0082]

[0083] Where semi-active control force There are Then we have:

[0084]

[0085] Among them, c f It represents the damping coefficient of the adjustable damper and is the semi-active control force F f The coefficient of sky represents the damping coefficient of the ideal ceiling damper, which is used in the ideal ceiling control strategy; x r Indicates the ideal floor shed position, used in floor shed control strategy.

[0086] The control strategy of this method is:

[0087]

[0088] C fmax Indicates the maximum damping coefficient that the adjustable damper can provide; C fmin Indicates the minimum damping coefficient that the adjustable damper can provide.

[0089] Ceiling switch (ON-OFF) control. The control current of the continuously changing magnetorheological damper is simplified to discrete changes, and only switches between the maximum and minimum damping that can be provided. The control strategy of this method is:

[0090]

[0091] Acceleration damping ON-OFF control: The ideal inertia container is installed in the suspension system, and the acceleration damping control is realized by controlling the magnetorheological damper with discrete changes in current. The control strategy of this method is:

[0092]

[0093] SH-ADD hybrid ON-OFF control: The skyhook control strategy can provide the best control effect in the low frequency band, while the acceleration-driven damping control can ensure the control effect in the high frequency band. Therefore, it is necessary to develop a control strategy that can combine the advantages of skyhook control and acceleration-driven damping control to achieve the best control performance. However, since the frequency of the road input cannot be directly obtained and the frequency cannot be directly distinguished, it is necessary to design a frequency band selector based on the signals of sensors such as acceleration. The hybrid algorithm of SH-ADD hybrid control is:

[0094]

[0095] in are the sprung vertical velocity and acceleration, is the vertical speed of the tire, It represents the vertical displacement of the vehicle body, that is, the change in the position of the vehicle body in the vertical direction. They are all parameters that can be directly measured by sensors or obtained through a numerical integration. α is the frequency limit between low frequency and high frequency and is the only adjustment parameter.

[0096] Step S30: controlling the semi-active suspension according to the target control strategy.

[0097] It should be noted that semi-active suspension is an advanced suspension technology that can dynamically adjust the damping force of the suspension to optimize the vehicle's handling and ride comfort according to the vehicle's actual operating conditions, such as road conditions, vehicle speed and vehicle acceleration. Although the semi-active suspension system cannot actively control the movement of the wheels, it can effectively reduce the vibration of the sprung part by adjusting the damping force, thereby improving the vehicle's stability and driving comfort.

[0098] It can be understood that the target control strategy is selected according to the current driving mode, such as the ceiling-acceleration hybrid damping control strategy, the floor-hinged linear semi-active control strategy or the ceiling-floor-hinged hybrid control strategy; the damping force of the semi-active suspension system is adjusted according to the selected strategy to adapt to the current driving conditions and road conditions; real-time data from acceleration sensors, suspension sensors, etc. are monitored and processed to achieve real-time adjustment of the damping force; and the system is ensured to be responsive and able to maintain good driving stability and ride comfort in different driving scenarios.

[0099] As an example, the step of controlling the semi-active suspension according to the target control strategy includes: when the target control strategy is a ground-shed linear semi-active control strategy, acquiring ground-shed sensor data, the ground-shed sensor data including the vehicle chassis motion state and the road surface unevenness; linearly adjusting the damping characteristics and wheel braking force in the semi-active suspension according to the vehicle chassis motion state, the road surface unevenness and a second preset linear control strategy.

[0100] The ground shed linear semi-active control strategy refers to a control method that adjusts the damping characteristics and wheel braking force in the semi-active suspension system according to the vehicle chassis motion state and the unevenness of the road surface, as well as the preset second linear control strategy. This strategy aims to provide a method of adjustment that balances comfort and handling performance. The ground shed sensor data includes information about the vehicle chassis motion state and the unevenness of the road surface. The vehicle chassis motion state can refer to dynamic parameters such as the acceleration and tilt angle of the vehicle; the unevenness of the road surface can be quantified by the data obtained by the ground shed sensor, such as the bumps and unevenness of the road surface. The vehicle chassis motion state refers to the dynamic state of the vehicle chassis during motion, including parameters such as acceleration, tilt angle, and body posture. The unevenness of the road surface refers to the unevenness, bumps, or other ground conditions that affect the operation of the vehicle suspension. The second preset linear control strategy is defined in this embodiment as a linear adjustment strategy for the semi-active suspension system, which is used to adjust the damping characteristics and wheel braking force according to the vehicle chassis motion state and the unevenness of the road surface to achieve the expected suspension response effect. The second preset linear control strategy is:

[0101]

[0102] The motion differential equation of the suspension system of this control strategy is:

[0103]

[0104] Where semi-active control force There are also:

[0105] Then there is

[0106] Among them, c ground Represents the damping coefficient in the ground shelf control strategy, used in the control force calculation related to the suspension system ground shelf.

[0107] Damping characteristics refer to the working characteristics of the damper in the semi-active suspension system, that is, the ability of the damper to control the movement of the suspension. The suspension response, comfort and stability of the vehicle can be improved by adjusting the damping characteristics. Wheel braking force refers to the braking force control of the semi-active suspension system on the wheel. By adjusting the braking force, the contact force and grip of the wheel under different road conditions can be affected. Linear adjustment refers to adjusting the damping characteristics and wheel braking force of the semi-active suspension system according to the vehicle chassis movement state, the unevenness of the road surface and the preset linear control strategy to achieve the desired linear response effect.

[0108] First, the ground shed sensor data is obtained, which includes two main aspects: the motion state of the vehicle chassis and the unevenness of the current road surface. The vehicle chassis motion state can cover the acceleration, tilt angle, and posture change of the vehicle body; the unevenness of the road surface is measured by the ground shed sensor, including information such as the bumpiness and jolt of the road surface. Next, according to the acquired vehicle chassis motion state, the unevenness of the road surface, and the preset second linear control strategy, the semi-active suspension system is linearly adjusted in terms of damping characteristics and wheel braking force, which means adjusting the damper working characteristics of the suspension system and the braking force applied to the wheel according to the real-time vehicle motion and road conditions. These adjustments are designed to optimize the response speed and stability of the semi-active suspension, improve the driving comfort and handling performance of the vehicle, and by accurately adjusting according to the ground shed sensor data and the preset control strategy, the semi-active suspension system can quickly respond to different road conditions and driving needs, thereby providing a smoother, more comfortable and safer driving experience.

[0109] As an example, the step of controlling the semi-active suspension according to the target control strategy includes: when the target control strategy is a ceiling-ground shelf hybrid control strategy, obtaining the motor angular acceleration and the steering wheel angle; when the motor angular acceleration is greater than a preset angular acceleration threshold, adjusting the adjustment coefficient of the proportion of the ceiling and ground shelf strategies to a preset adjustment coefficient value; when the motor angular acceleration is less than or equal to the preset angular acceleration threshold and the steering wheel angle is greater than a preset angle threshold, adjusting the adjustment coefficient in the form of a normal distribution of the steering wheel angle; when the motor angular acceleration is less than or equal to the preset angular acceleration threshold and the steering wheel angle is less than or equal to the preset angle threshold, adjusting the adjustment coefficient to a preset balance coefficient; and controlling the semi-active suspension according to the adjustment coefficient, the ground shelf linear semi-active control strategy, and the ceiling-acceleration hybrid damping control strategy.

[0110] The ceiling-ground-shelf hybrid control strategy is a semi-active suspension control strategy that adjusts the suspension characteristics by adjusting the proportion of the ceiling (roof) and ground-shelf (chassis) strategies. Specifically, by changing the proportion of the two strategies, the response performance and comfort of the suspension can be adjusted. The motor angular acceleration refers to the parameter used to monitor the angle change rate of the motor per unit time in the semi-active suspension system. When the motor angular acceleration exceeds the preset angular acceleration threshold, the system will make corresponding adjustments to adapt to the driving situation. The steering wheel angle refers to the angle measurement of the driver's steering wheel rotation. The system adjusts the suspension response characteristics according to the size and change of the steering wheel angle to provide better handling and comfort. The preset angular acceleration threshold refers to the threshold of the motor angular acceleration set in advance. Exceeding this threshold will trigger the adjustment of the suspension control strategy. The adjustment coefficient refers to the parameter that adjusts the proportion of the ceiling and ground-shelf strategies according to the motor angular acceleration and the steering wheel angle. By adjusting this coefficient, the performance of the suspension can be optimized to adapt to different driving conditions. The preset adjustment coefficient value refers to a pre-set default value. Specifically, when the motor angular acceleration exceeds the set threshold, it indicates that the vehicle may be in an acceleration or braking state. At this time, the system will adjust the adjustment coefficient to the preset adjustment coefficient value (0 in this embodiment, in order to fully adopt the ground shelf control strategy to optimize the road adhesion performance of the suspension system). The preset angle threshold refers to the preset threshold of the steering wheel angle. When the steering wheel angle exceeds or falls below this threshold, different suspension adjustment strategies will be triggered. The normal distribution form means that under certain conditions, the system adjusts the adjustment coefficient in a normally distributed manner according to the steering wheel angle to balance the performance requirements of the suspension under various driving conditions. The normal distribution (also called the Gaussian distribution) is a common statistical distribution with a bell-shaped curve shape, the mean is located at the center of the distribution, and the standard deviation determines the width of the distribution and the steepness of the shape. The preset balance coefficient refers to the value of the adjustment coefficient set when the vehicle is in a balanced state, which is 0.7 in this embodiment. Specifically, when the vehicle is in a balanced state, that is, the motor angular acceleration is less than or equal to the preset angular acceleration threshold and the steering wheel angle is less than or equal to the preset angle threshold, the system will set the adjustment coefficient to the preset balance coefficient value of 0.7. The selection of this value is determined through engineering practice and performance testing. The purpose is to provide good suspension response under different driving conditions, which can not only ensure driving smoothness, but also maintain good road adhesion, so as to enhance vehicle stability and driving comfort.The significance of adjusting the adjustment coefficient in the form of normal distribution is to dynamically adjust the suspension control strategy according to the size of the steering wheel angle. Specifically, when the motor angular acceleration is less than or equal to the preset angular acceleration threshold and the steering wheel angle is greater than the preset angle threshold, the system will determine the size of the adjustment coefficient according to the specific value of the steering wheel angle. The normal distribution allows the system to provide a more sensitive suspension response when the angle is larger, while maintaining a relatively stable control strategy when the angle is smaller (2% of the maximum value at ±90°) to balance the needs between comfort and suspension performance.

[0111] Please refer to Figure 2 , Figure 2 The schematic diagram of the process flow of adjusting the adjustment coefficient in the adaptive mode provided in the first embodiment of the control method of the semi-active suspension of the present application shows the process of adjusting the adjustment coefficient in the ceiling-ground canopy hybrid control strategy in the adaptive mode, and the system intelligently responds to the suspension control requirements of the vehicle under different driving conditions. First, it is identified whether the vehicle is in the adaptive mode, and then the dynamic state of the vehicle is obtained by analyzing the speed signal of the motor. When the motor angular acceleration is detected to exceed the preset threshold, the system determines that the vehicle is accelerating or braking. At this time, the adjustment coefficient α is set to 0, so that the control strategy is completely inclined to ground canopy control to optimize the road adhesion. If the motor angular acceleration does not exceed the threshold but the steering wheel angle exceeds the set value, the system determines that the vehicle is turning, and the adjustment coefficient will be adjusted according to the normal distribution according to the angle size to ensure that sufficient road adhesion is provided when turning at a large angle. For the case where the above two states are not triggered, the system considers that the vehicle is in a balanced state and sets the adjustment coefficient α to 0.7 to achieve a comprehensive consideration of smoothness and road adhesion. The entire process realizes real-time optimization control of the suspension system by dynamically adjusting the adjustment coefficient to adapt to different driving scenarios and improve the vehicle's handling and ride comfort.

[0112] Please refer to Figure 3 , Figure 3A schematic diagram of the normal distribution relationship between the steering wheel angle and the adjustment coefficient provided in the first embodiment of the control method of the semi-active suspension of the present application shows the dependence between the steering wheel angle and the adjustment coefficient α. In the form of a normal distribution curve, it accurately reflects how the suspension control system dynamically adjusts the adjustment coefficient according to the amplitude of the steering input in the adaptive mode. At a steering wheel angle of 0 degrees, that is, when the vehicle is driving in a straight line, the adjustment coefficient is set to 0.7, which balances the smoothness and road adhesion of the suspension system. As the steering wheel angle increases or decreases, the adjustment coefficient begins to rise according to the normal distribution curve. When the steering wheel angle reaches ±90°, the adjustment coefficient reaches 2% of its maximum value. This is to provide additional road adhesion when turning at a large angle to ensure the handling stability of the vehicle. The smooth change of the curve ensures the continuity and stability of the adjustment coefficient, avoids the abrupt adjustment of the suspension system during steering, and thus achieves a smooth transition and optimal performance of the suspension system under various steering inputs. This adjustment strategy based on steering input enables the suspension system to intelligently adapt to the driver's steering operation and provide a more precise and comfortable driving experience.

[0113] First, the data of the motor angular acceleration and the steering wheel angle are obtained. If the motor angular acceleration is greater than the preset angular acceleration threshold, the system will adjust the adjustment coefficient of the proportion of the ceiling and floor strategies to the preset adjustment coefficient value to optimize the road adhesion performance. When the motor angular acceleration is less than or equal to the preset angular acceleration threshold and the steering wheel angle is greater than the preset angle threshold, the system will adjust the steering wheel angle according to the normal distribution form to fine-tune the adjustment coefficient. When the motor angular acceleration is less than or equal to the preset angular acceleration threshold and the steering wheel angle is less than or equal to the preset angle threshold, the system sets the adjustment coefficient to the preset balance coefficient to balance the driving smoothness and road adhesion performance. Finally, according to the setting of the adjustment coefficient, combined with the floor shelf linear semi-active control strategy and the ceiling-acceleration hybrid damping control strategy, the semi-active suspension is precisely controlled to ensure that the driver can obtain the best suspension performance and driving experience under various driving conditions.

[0114] This embodiment provides a control method for a semi-active suspension. When there is no fault in the vehicle system, the driving mode is distinguished according to the mode selection signal to obtain the current driving mode; when the current driving mode is not the speed bump mode, the target control strategy is determined according to the current driving mode; and the semi-active suspension is controlled according to the target control strategy. This embodiment first distinguishes the driving mode according to the mode selection signal, which means that the system determines the current driving mode according to the received signal, which may include a comfort mode, a sports mode, an adaptive mode, etc. These modes will affect the working mode of the vehicle suspension and transmission system. When it is determined that the current driving mode is not the speed bump mode, the system will select the corresponding target control strategy according to the current driving mode. For example, the comfort mode may give priority to providing a smooth driving experience, the sports mode may emphasize power output and suspension rigidity, and the adaptive mode will automatically adjust according to the real-time driving conditions and road conditions to balance comfort and performance. Finally, according to the determined target control strategy, the system accurately controls the semi-active suspension. This includes adjusting the damping characteristics of the suspension, wheel braking force and other parameters according to the strategy to ensure that the suspension system can provide the best suspension performance and driving experience under different driving modes. This embodiment can adjust the vehicle suspension system according to different driving needs and road conditions, providing a better driving experience and safety. Through precise control strategies, the driver can switch between comfort and sport driving modes, while obtaining better vehicle stability and handling performance under different road conditions, improving the vehicle's smoothness and road adhesion, and improving overall driving comfort and safety.

[0115] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can refer to the above introduction, and will not be repeated later. Figure 4 , Figure 4 This is a flow chart of a second embodiment of the control method of the semi-active suspension of the present application. Step S30 of the control method of the semi-active suspension includes steps S31 to S34:

[0116] Step S31, when the target control strategy is a ceiling-acceleration hybrid damping control strategy, obtaining ceiling sensor data, wherein the ceiling sensor data includes a vehicle body height change;

[0117] It should be noted that the ceiling-acceleration hybrid damping control strategy is a vehicle suspension control strategy that combines ceiling sensor data and vehicle acceleration information to adjust the damping characteristics of the suspension. Specifically, by comprehensively considering the dynamic acceleration changes of the vehicle and the vertical movement of the vehicle body, the damping settings of the suspension are adjusted to achieve better driving comfort and stability. Ceiling sensor data refers to information collected by sensors installed in the ceiling area of ​​the vehicle. In this embodiment, the ceiling sensor is mainly used to measure changes in vehicle body height, which can be achieved by detecting the relative height changes of the vehicle body in motion or at rest. Vehicle body height changes refer to changes in the vertical direction of the vehicle body measured by the vehicle ceiling sensor. This change can be used to evaluate the dynamic response and posture adjustment of the vehicle under different driving conditions, thereby helping to adjust the damping force of the suspension to ensure appropriate suspension support and comfort in different driving modes.

[0118] It is understandable that under the ceiling-acceleration hybrid damping control strategy, the system first obtains ceiling sensor data, which includes information on changes in vehicle height. By measuring changes in the vertical direction of the vehicle body through the ceiling sensor, the system can monitor the changes in the vehicle's posture and the impact of road conditions on the vehicle height in real time. These data are crucial for the semi-active suspension system because they are used to adjust the damping characteristics of the suspension to adapt to different driving conditions and road conditions. By comprehensively considering the vehicle's dynamic acceleration and changes in vehicle height, the system can accurately adjust the working mode of the suspension to provide optimized driving comfort and stability.

[0119] Step S32, calculating a road surface excitation value according to the acceleration sensor data;

[0120] It should be noted that the road excitation value refers to the vibration or unevenness level of the road surface calculated based on the acceleration sensor data. The acceleration sensor can detect the acceleration changes of the vehicle on different road surfaces. These changes reflect the excitation conditions of the road surface, that is, the degree of influence of the road surface on the vehicle.

[0121] It is understandable that the acceleration sensor data of the vehicle during driving is first collected and analyzed, which reflects the vibration and dynamic changes of the vehicle on different road surfaces. By analyzing the acceleration data in the time domain or frequency domain, the road excitation information can be extracted, that is, the unevenness or vibration level of the road surface, which is crucial for the vehicle suspension system because they affect the damping characteristics and response speed of the suspension. The calculated road excitation value can be used to optimize the suspension adjustment strategy to provide better driving comfort and stability, while ensuring the safety and performance of the vehicle under different road conditions.

[0122] Step S33, obtaining the frequency band of the current road;

[0123] It should be noted that the frequency band refers to the vibration frequency range caused by the vibration or unevenness of the road surface. Specifically, it refers to the frequency distribution range of the vertical vibration of the wheels caused by the uneven road surface during driving.

[0124] It is understood that the vibration frequency range of the road that the vehicle passes through during driving is obtained through a sensor or system. This step involves using sensors equipped on the vehicle, such as accelerometers or other related sensors, to capture vehicle vibration information caused by uneven road surfaces. By analyzing these vibration data, the system is able to identify the frequency characteristics of the road surface, that is, the frequency band of the road. This information is very important for the semi-active suspension system because it helps the system adjust the working mode and parameters of the suspension according to different road conditions, thereby improving the comfort and stability of the vehicle.

[0125] Step S34 , linearly adjusting the damping characteristics of the semi-active suspension according to the vehicle height change, the road excitation value, the frequency band, and a first preset linear control strategy.

[0126] It should be noted that the first preset linear control strategy refers to a preset strategy based on a linear control algorithm, which is used to adjust the damping characteristics of the semi-active suspension system. This strategy determines the optimal damping adjustment by real-time monitoring of vehicle height changes, calculating road excitation values, and analyzing the frequency band of the current road. Specifically, the damping is adjusted according to changes in vehicle height to cope with vibrations caused by uneven road surfaces; the impact intensity of the road surface is evaluated according to the road excitation value, and the damping is adjusted accordingly; at the same time, according to the analysis of the road frequency band, the damping is adjusted for vibrations of different frequencies to improve the comfort of the vehicle and the stability of the suspension. The first preset linear control strategy is:

[0127]

[0128] In the formula can be considered as a "band selector", considering a single-frequency excitation signal Define the function f(t) as Will Substituting into f(t) we get:

[0129] f(t)=A 2 ω 2 -A 2 sin 2 (ωt)(α 2 +ω 2 )

[0130] Consider f(t) in a cycle The positive and negative inside can be easily obtained:

[0131]

[0132] When f(t)>0, a domain |D is given + (ω)|, which is defined as {D + (ω)=t:f(t)>0,0≤t≤T}, according to the above formula, it is easy to get the criterion:

[0133]

[0134] From the above formula, we can get that domain |D + The corresponding relationship between the normalized time and frequency ω of (ω)| is:

[0135]

[0136] It can be seen that within a period T, when the frequency of the single-frequency excitation signal ω>α, f(t)>0 in more than half of the interval; when ω<α, f(t)<0 in more than half of the interval.

[0137] Please refer to Figure 5 , Figure 5 The schematic diagram of the frequency response characteristics of the SH-ADD control strategy provided in the second embodiment of the control method of the semi-active suspension of the present application shows a detailed view of the key parameters of the frequency response characteristics of the SH-ADD control strategy changing over time, which is reflected by the periodic changes of the sine function. The sine waveform sin(ωt) in the figure is 2 Represents the frequency component of the excitation signal, and is used to describe the system's response amplitude to different frequency components. The horizontal axis represents time, and the vertical axis represents the normalized response amplitude, where α represents a parameter related to the system damping or frequency selectivity. The curve in the figure shows how the excitation signals of different frequency components are affected by the system response amplitude as time changes. In the SH-ADD control strategy, this frequency response characteristic is crucial to achieving the optimization of smoothness and stability, because it allows the system to dynamically adjust the damping force according to road conditions and vehicle driving conditions, thereby providing the best control effect in different frequency bands. By analyzing this figure, we can have a deeper understanding of how the SH-ADD control strategy balances the comfort and handling of the suspension system through the frequency band selector. When ω>α, Figure 5 Medium 2 / (α 2 +ω) 2 The dashed line shown will be above 0.5, thus making sin(ωt) 2 The part below the dotted line is larger than the part above the dotted line, that is, |D_+(ω)| / T>1 / 2, which means that f(t)>0 is more than half of the interval range; conversely, it means that f(t)<0 is more than half of the interval range. Therefore It can be considered as a frequency band selector, centered on the frequency ω=α: when f(t)>0, it can be considered that ω>α, otherwise ω<α.

[0138] It can be understood that first, the real-time suspension working status information is obtained by monitoring the change in vehicle body height, which reflects the dynamic response of the vehicle under different road conditions; then, the unevenness of the road surface and the intensity of its impact on the vehicle are evaluated based on the calculated road excitation value, and this information is crucial for the damping adjustment of the suspension; then, the frequency band of the current road, that is, the vibration of the road surface at different frequencies, is analyzed in order to accurately adjust the damping characteristics of the suspension; finally, combined with the first preset linear control strategy, a linear adjustment method is used to fine-tune the damping of the semi-active suspension to improve the driving comfort and stability of the vehicle and ensure that the suspension system can provide optimal performance under various road conditions.

[0139] In this embodiment, when the target control strategy is the ceiling-acceleration hybrid damping control strategy, the ceiling sensor data is obtained, and the ceiling sensor data includes the change in vehicle height; the road surface excitation value is calculated according to the acceleration sensor data; the frequency band of the current road is obtained; and the damping characteristics in the semi-active suspension are linearly adjusted according to the change in vehicle height, the road surface excitation value, the frequency band and the first preset linear control strategy. In this embodiment, first, when the target control strategy is the ceiling-acceleration hybrid damping control strategy, by obtaining the ceiling sensor data, especially the change in vehicle height, the system can monitor and evaluate the suspension working state of the vehicle in real time, which is crucial for adjusting the response and stability of the suspension. Secondly, the acceleration sensor data is used to calculate the road surface excitation value, which reflects the unevenness and vibration intensity of the road surface, and helps the system understand the degree of influence of the current road condition on the vehicle suspension. Next, the frequency band information of the current road is obtained, that is, the characteristics of road surface vibration at different frequencies, which is crucial for accurately adjusting the damping characteristics of the suspension to cope with the unevenness of the road surface at different frequencies. Finally, according to the change in vehicle height, road excitation value, frequency band information and preset linear control strategy, the system linearly adjusts the damping characteristics of the suspension. This fine adjustment can optimize the suspension's response speed and vibration suppression capabilities, thereby improving the vehicle's driving comfort and stability, while ensuring consistency and superior performance in driving performance under various road conditions.

[0140] For example, in order to help understand the implementation process of the control method of the semi-active suspension obtained by combining this embodiment with the above-mentioned embodiment 1, please refer to Figure 6 , Figure 6 A brief flow chart of a control method for a semi-active suspension is provided, specifically:

[0141] The figure shows the switching logic and control flow of different modes in the semi-active suspension system, clearly depicting the complete logic chain from signal acquisition to mode judgment and then to control strategy execution.

[0142] Mode 1 - Comfort mode: In this mode, the system uses SH-ADD (ceiling-acceleration hybrid damping control strategy) for control. First, the signal is obtained through the acceleration sensor and judged by the electrical signal. After the signal is filtered by the second-order Butterworth filter, the system determines whether to enter the speed bump mode based on the filtering result. Mode 2 - Sports mode: In the sports mode, the system also uses the acceleration sensor to monitor the vertical acceleration of the vehicle body and the acceleration of the wheels. The signal is first filtered, and then the fault diagnosis is used to determine whether the system has a fault. If there is no fault, the system will perform speed bump judgment and driving mode judgment. Mode 3 - Adaptive mode: The adaptive mode uses the controller area network (CAN) communication signal to obtain information such as steering wheel angle and engine / motor speed. The system first determines whether the speed bump mode needs to be maintained, and then determines whether it is in the speed bump mode based on the wheel acceleration and suspension travel. If it is not the speed bump mode, the system will use the ceiling-ground shed hybrid control strategy for active adjustment. Mode 4 - Passive vibration reduction mode: When the system detects a fault, it will switch to the passive vibration reduction mode. In this mode, the system uses passive damping to maintain time, and determines whether to release the speed bump mode through the brake pedal travel signal. Speed ​​bump mode judgment: All modes contain the judgment logic of the speed bump mode. The system will check whether the current value exceeds the set threshold. If so, the speed bump mode will be maintained; if not, the speed bump mode will be released (the speed bump mode is also a driving mode, and the other 4 are general driving modes). Signal filtering: In multiple modes, signal filtering is a key step. A second-order Butterworth filter is used to smooth the sensor signal and reduce noise interference. Fault diagnosis: The system determines whether there is a fault by comparing the controller output and the suspension output. If the difference between the two exceeds the threshold, it is determined that a fault has occurred and switched to the passive vibration reduction mode. Control strategy: According to the current mode and sensor signal, the system selects the corresponding control strategy, such as SH-ADD linear hybrid control, ground-shed linear semi-active control, or ceiling-ground-shed hybrid control.

[0143] In comfort mode, the system receives signals through the acceleration sensor and uses a second-order Butterworth filter for filtering, and then determines whether to activate the speed bump mode based on the filtering results. In sports mode, the system again relies on the acceleration sensor to monitor the acceleration of the vehicle body and wheels, performs fault diagnosis, and continues to execute the speed bump judgment and driving mode judgment criteria in the absence of faults. The adaptive mode comprehensively utilizes the steering wheel angle and engine / motor speed information in the CAN communication signal to first confirm whether to maintain the speed bump mode, and then actively adjusts the ceiling-ground canopy hybrid control strategy based on the wheel acceleration and suspension travel. When the system detects a fault, it automatically switches to the passive vibration reduction mode, uses passive damping and determines whether to exit the speed bump mode based on the brake pedal travel signal. In the entire process, signal filtering is a key step to reduce noise and improve signal quality, while fault diagnosis ensures the reliability and safety of the system. The system intelligently selects the most appropriate control strategy based on real-time sensor data and preset logic. Whether it is SH-ADD linear hybrid control, floor-shed linear semi-active control, or ceiling-floor-shed hybrid control, it aims to achieve the best performance of the suspension system, provide a smooth driving experience, and ensure the vehicle's handling and stability.

[0144] It should be noted that the above examples are only used to understand the present application and do not constitute a limitation on the control method of the semi-active suspension of the present application. More simple transformations based on this technical concept are all within the scope of protection of the present application.

[0145] The present application also provides a control device for a semi-active suspension, please refer to Figure 7 , the control device of the semi-active suspension comprises:

[0146] The mode distinguishing module 10 is used to distinguish the driving mode according to the mode selection signal to obtain the current driving mode when there is no fault in the vehicle system;

[0147] A strategy selection module 20, for determining a target control strategy according to the current driving mode when the current driving mode is not a speed bump mode;

[0148] The control module 30 is used to control the semi-active suspension according to the target control strategy.

[0149] The control device of the semi-active suspension provided in the present application adopts the control method of the semi-active suspension in the above-mentioned embodiment, and can solve the technical problem of how to improve the smoothness and road adhesion of the vehicle. Compared with the prior art, the beneficial effects of the control device of the semi-active suspension provided in the present application are the same as the beneficial effects of the control method of the semi-active suspension provided in the above-mentioned embodiment, and the other technical features in the control device of the semi-active suspension are the same as the features disclosed in the above-mentioned embodiment method, which will not be repeated here.

[0150] The present application provides a control device for a semi-active suspension, the control device for the semi-active suspension comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the control method for the semi-active suspension in the above-mentioned embodiment one.

[0151] Reference below Figure 8 , which shows a schematic diagram of the structure of a control device suitable for implementing a semi-active suspension in an embodiment of the present application. The control device of the semi-active suspension in an embodiment of the present application may include, but is not limited to, mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Descriptions), PMPs (Portable Media Players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc. Figure 8 The control device of the semi-active suspension shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0152] like Figure 8As shown, the control device of the semi-active suspension may include a processing device 1001 (e.g., a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In the RAM 1004, various programs and data required for the operation of the control device of the semi-active suspension are also stored. The processing device 1001, the ROM 1002, and the RAM 1004 are connected to each other via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems may be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touchpad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 may allow the control device of the semi-active suspension to communicate with other devices wirelessly or by wire to exchange data. Although the control device of the semi-active suspension having various systems is shown in the figure, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems may be implemented or have instead.

[0153] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0154] The control device of the semi-active suspension provided in the present application adopts the control method of the semi-active suspension in the above embodiment, which can solve the technical problem of how to improve the smoothness and road adhesion of the vehicle. Compared with the prior art, the beneficial effects of the control device of the semi-active suspension provided in the present application are the same as the beneficial effects of the control method of the semi-active suspension provided in the above embodiment, and the other technical features in the control device of the semi-active suspension are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0155] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0156] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0157] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the control method of the semi-active suspension in the above-mentioned embodiment.

[0158] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination of the above.

[0159] The computer-readable storage medium may be included in the control device of the semi-active suspension; or may exist independently without being assembled into the control device of the semi-active suspension.

[0160] The above-mentioned computer-readable storage medium carries one or more programs. When the above-mentioned one or more programs are executed by the control device of the semi-active suspension, the control device of the semi-active suspension: when there is no fault in the vehicle system, distinguish the driving mode according to the mode selection signal to obtain the current driving mode; when the current driving mode is not a speed bump mode, determine the target control strategy according to the current driving mode; and control the semi-active suspension according to the target control strategy.

[0161] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0162] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0163] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0164] The readable storage medium provided in the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned control method of the semi-active suspension, and can solve the technical problem of how to improve the ride comfort and road adhesion of the vehicle. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in the present application are the same as the beneficial effects of the control method of the semi-active suspension provided in the above-mentioned embodiment, and will not be elaborated here.

[0165] The present application also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the steps of the control method of the semi-active suspension as described above are implemented.

[0166] The computer program product provided in this application can solve the technical problem of how to improve the ride comfort and road adhesion of the vehicle. Compared with the prior art, the beneficial effects of the computer program product provided in this application are the same as the beneficial effects of the control method of the semi-active suspension provided in the above embodiment, which will not be described in detail here.

[0167] The above descriptions are only some embodiments of the present application, and are not intended to limit the patent scope of the present application. All equivalent structural changes made using the contents of the present application specification and drawings under the technical concept of the present application, or direct / indirect applications in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A control method for a semi-active suspension, It is characterized in that The method comprises: When there is no fault in the vehicle system, the driving mode is distinguished according to the mode selection signal to obtain the current driving mode; When the current driving mode is not a speed bump mode, determining a target control strategy according to the current driving mode; The semi-active suspension is controlled according to the target control strategy.

2. The method according to claim 1, It is characterized in that The step of controlling the semi-active suspension according to the target control strategy comprises: When the target control strategy is a ceiling-acceleration hybrid damping control strategy, obtaining ceiling sensor data, wherein the ceiling sensor data includes a height change of a vehicle body; Calculating a road surface excitation value according to the acceleration sensor data; Get the frequency band of the current road; The damping characteristic in the semi-active suspension is linearly adjusted according to the vehicle height change, the road excitation value, the frequency band and a first preset linear control strategy.

3. The method according to claim 1, It is characterized in that The step of controlling the semi-active suspension according to the target control strategy comprises: When the target control strategy is a ground-shed linear semi-active control strategy, acquiring ground-shed sensor data, wherein the ground-shed sensor data includes a vehicle chassis motion state and a road surface unevenness; The damping characteristics and wheel braking force in the semi-active suspension are linearly adjusted according to the vehicle chassis motion state, the road surface unevenness and a second preset linear control strategy.

4. The method according to claim 1, It is characterized in that The step of controlling the semi-active suspension according to the target control strategy comprises: When the target control strategy is a ceiling-ground ceiling hybrid control strategy, obtaining a motor angular acceleration and a steering wheel angle; When the motor angular acceleration is greater than a preset angular acceleration threshold, the adjustment coefficient of the proportion of the ceiling and floor strategies is adjusted to a preset adjustment coefficient value; When the motor angular acceleration is less than or equal to the preset angular acceleration threshold and the steering wheel angle is greater than the preset angle threshold, adjusting the adjustment coefficient of the steering wheel angle in a normal distribution form; When the motor angular acceleration is less than or equal to the preset angular acceleration threshold and the steering wheel angle is less than or equal to the preset angle threshold, adjusting the adjustment coefficient to a preset balance coefficient; The semi-active suspension is controlled according to the adjustment coefficient, the floor-hook linear semi-active control strategy and the sky-hook-acceleration hybrid damping control strategy.

5. The method according to claim 1, It is characterized in that After the step of distinguishing the driving modes according to the mode selection signal to obtain the current driving mode, the method further includes: When the current driving mode is a speed bump mode, the spring load is controlled by a smoothness mode strategy; Acquiring the current vehicle speed, and calculating the time to maintain the speed reduction mode according to the current vehicle speed; If it is detected again that the vehicle passes through the speed bump within the time, the process returns to the step of obtaining the current vehicle speed and calculating the time to maintain the speed bump mode according to the current vehicle speed.

6. The method according to claim 5, It is characterized in that Before the step of controlling the sprung load by using the smoothness mode strategy when the current driving mode is the speed bump mode, the method further includes: Filtering the acceleration sensor data to obtain filtered data, wherein the filtered data includes wheel acceleration and suspension travel; determining a wheel center vertical acceleration according to the wheel acceleration; When the wheel center vertical acceleration and the suspension dynamic travel are both greater than or equal to a preset threshold, determining that the current driving mode is a speed bump mode; When the wheel center vertical acceleration or the suspension dynamic stroke is less than the preset threshold, it is determined that the current driving mode is not a speed bump mode.

7. The method according to any one of claims 1 to 6, It is characterized in that Before the step of distinguishing the driving modes according to the mode selection signal to obtain the current driving mode when there is no fault in the vehicle-mounted system, the method further includes: Determining a fault condition of the vehicle-mounted system based on acceleration sensor data and controller area network communication data; When the vehicle-mounted system fails, the driving mode is switched to a passive vibration reduction mode.

8. A control device for a semi-active suspension, It is characterized in that The device comprises: A mode distinguishing module is used to distinguish the driving mode according to the mode selection signal to obtain the current driving mode when there is no fault in the vehicle system; A strategy selection module, configured to determine a target control strategy according to the current driving mode when the current driving mode is not a speed bump mode; A control module is used to control the semi-active suspension according to the target control strategy.

9. A control device for a semi-active suspension, It is characterized in that The device comprises: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the computer program is configured to implement the steps of the control method for a semi-active suspension according to any one of claims 1 to 7.

10. A storage medium, It is characterized in that The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, the steps of the control method of the semi-active suspension according to any one of claims 1 to 7 are implemented.

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