Control method and system for roll suppression of a vehicle with a hydraulic active suspension and vehicle

Abstract

The application provides a control method and system based on hydraulic active suspension vehicle roll suppression and a vehicle, and belongs to the technical field of intelligent automobile chassis suspension control, and comprises the following steps: acquiring a vehicle speed, a steering wheel rotation angle and a rotation angle acceleration signal; when the vehicle speed signal reaches a preset vehicle speed threshold and the steering wheel rotation angle signal reaches a preset rotation angle threshold, roll suppression is performed; a motor speed target value and an electromagnetic valve current target value are acquired according to the steering wheel rotation angle acceleration signal in combination with the vehicle speed and the steering wheel rotation angle signal, and the target values are executed; when an actual vehicle body height difference exceeds a preset range of a target vehicle body height difference, the motor speed target value and the electromagnetic valve current target value are corrected in real time; the vehicle roll is controlled in a target range according to the corrected motor speed target value and the electromagnetic valve current target value in real time, and the above process is repeatedly executed in a loop. The application improves the vehicle control stability and safety.

Description

Technical Field

[0001] This invention belongs to the field of intelligent vehicle chassis suspension control technology, and particularly relates to a control method, system and vehicle for suppressing vehicle roll based on hydraulic active suspension. Background Technology

[0002] Vehicles are prone to body roll when turning at high speeds or making emergency maneuvers. Traditional suspensions are designed with moderate stiffness to balance comfort. When a vehicle rolls, the suspension does not contribute enough to the vehicle's handling and stability. Excessive roll angle can lead to a lack of driver confidence and may even pose a rollover risk.

[0003] The dual-chamber air suspension employs a two-stage stiffness adjustment scheme. The primary stiffness level prioritizes comfort, while the secondary stiffness level addresses roll conditions. However, this scheme exhibits non-linear adjustment. When the vehicle rolls and the secondary stiffness level is not triggered, or when the roll acceleration is significant after the secondary stiffness level is triggered, the vehicle's handling stability remains poor. Furthermore, active suspension roll control schemes typically distribute and compensate for control forces based on roll angle or lateral acceleration signals, but they cannot provide linear and precise control of the lateral support stiffness according to different roll accelerations, making it difficult to simultaneously meet both comfort and handling stability requirements. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, this invention proposes a control method, system, and vehicle based on hydraulic active suspension for vehicle roll suppression. This addresses the problems in the prior art where the two-stage stiffness adjustment is nonlinear, resulting in poor vehicle handling and stability; and the inability to achieve linear and precise control of lateral support stiffness based on roll angle or lateral acceleration signals for control force distribution, which fails to generate corresponding lateral support stiffness according to different roll accelerations.

[0005] To achieve the above objectives, one or more embodiments of the present invention provide the following technical solutions: In a first aspect, the present invention discloses a control method for suppressing vehicle roll based on hydraulic active suspension, comprising: The vehicle speed, steering wheel angle, and steering acceleration signals are acquired. When the vehicle speed signal reaches a preset vehicle speed threshold and the steering wheel angle signal reaches a preset angle threshold, roll suppression is performed. The system performs a feedforward judgment for roll suppression based on the steering wheel angle acceleration signal, combines the vehicle speed and steering wheel angle signals to obtain the target values ​​for motor speed and solenoid valve current, and then executes the target values. The actual height difference between the left and right sides of the vehicle is compared with the preset target height difference; when the actual height difference exceeds the preset range of the target height difference, the target values ​​of the motor speed and the solenoid valve current are corrected in real time. Based on the corrected target values ​​for motor speed and solenoid valve current, the vehicle tilt is controlled in real time within the target range, and the above process is repeated cyclically.

[0006] A further technical solution involves using the steering wheel angle acceleration signal for feedforward judgment to generate the changing trend of the roll suppression target: When the steering wheel angle acceleration signal is greater than zero, it indicates that the steering wheel is accelerating to the right, and the vehicle is predicted to tilt to the right; when the steering wheel angle acceleration signal is less than zero, it indicates that the steering wheel is accelerating to the left, and the vehicle is predicted to tilt to the left.

[0007] A further technical solution involves using the steering wheel angle acceleration signal to perform feedforward judgment for roll suppression, and combining the vehicle speed and steering wheel angle signals to obtain the target values ​​for motor speed and solenoid valve current, including: The target value is obtained by looking up a multidimensional mapping table. or, The target value is obtained by using a vehicle dynamics calculation model with vehicle speed, steering wheel angle, and steering wheel angle acceleration signals as inputs.

[0008] A further technical solution, wherein the method of obtaining the target value by looking up a multidimensional mapping table, specifically involves: The angular acceleration signal, along with the vehicle speed and steering wheel angle, are used as input parameters. A pre-stored multidimensional mapping table is consulted to directly obtain the target values ​​of the motor speed and solenoid valve current for the next moment. The multidimensional mapping table is obtained through actual vehicle calibration.

[0009] A further technical solution involves real-time correction of the target values ​​for motor speed and solenoid valve current, including functional safety verification and target value verification and correction. The functional safety verification is performed by calculating the height difference between the left and right sides based on the height sensor signal of the current vehicle status, and comparing the calculated target active force direction. When the upward target active force and the lower side are on the same side, or the downward target active force and the higher side are on the same side, the action is executed. When they are not on the same side, the action is stopped.

[0010] A further technical solution is that the target value verification and correction is as follows: when the actual vehicle height difference exceeds the preset deviation range, the correction amount of the motor speed under the current height deviation is obtained through the calibration correspondence between the height deviation and the motor speed, and the correction amount is added to the target value to obtain the current motor speed value.

[0011] Secondly, the present invention discloses a control system for vehicle roll suppression based on hydraulic active suspension, comprising: The data acquisition module is used to acquire vehicle speed, steering wheel angle and angular acceleration signals. When the vehicle speed signal reaches a preset vehicle speed threshold and the steering wheel angle signal reaches a preset angle threshold, roll suppression is performed. The feedforward judgment module is used to make feedforward judgments for roll suppression based on the steering wheel angle acceleration signal. It combines the vehicle speed and steering wheel angle signals to obtain the target values ​​of motor speed and solenoid valve current, and then executes the target values. The target correction module is used to compare the actual height difference between the left and right sides of the vehicle with the preset target height difference; when the actual height difference exceeds the preset range of the target height difference, the target values ​​of the motor speed and the solenoid valve current are corrected in real time. The loop optimization module is used to control the vehicle tilt within the target range in real time based on the corrected target values ​​of motor speed and solenoid valve current, and repeat the above process in a loop.

[0012] Thirdly, the present invention discloses a vehicle, including a memory and a processor, and computer instructions stored in the memory and running on the processor, wherein the computer instructions, when run by the processor, complete the steps of the above-described control method for suppressing vehicle roll based on hydraulic active suspension.

[0013] Fourthly, the present invention discloses a computer-readable storage medium for storing computer instructions, which, when executed by a processor, complete the steps of the above-described control method for suppressing vehicle roll based on hydraulic active suspension.

[0014] Fifthly, the present invention discloses a computer program product comprising executable instructions stored in a computer-readable storage medium; wherein, when the vehicle's processor reads and executes the executable instructions from the computer-readable storage medium, it completes the steps of the aforementioned control method for suppressing vehicle roll based on hydraulic active suspension.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention utilizes a complete closed-loop logic collaborative control system, encompassing signal recognition, algorithm control, real-vehicle verification, and algorithm correction, to effectively reduce the risk of control failure and achieve precise active control of vehicle roll. By using the steering wheel angle acceleration signal as a factor in calculating the actuator's target value for the next moment, system response delay is effectively reduced, enabling rapid response and improving roll suppression. Furthermore, by using a height sensor to acquire the actual height difference between the left and right sides of the vehicle in real time, and performing closed-loop comparison and correction with the target height difference, the invention ensures that vehicle roll is controlled within the target range in real time, improving the accuracy and reliability of control.

[0016] Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0017] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0018] Figure 1 This is a flowchart of the vehicle roll suppression control method based on hydraulic active suspension as described in Embodiment 1 of the present invention.

[0019] Figure 2 This is an algorithm logic diagram of the control method for suppressing vehicle roll based on hydraulic active suspension as described in Embodiment 1 of the present invention.

[0020] Figure 3 This is a schematic diagram of the chassis domain controller described in Embodiment 1 of the present invention.

[0021] Figure 4 This is a structural block diagram of the control system for suppressing vehicle roll based on hydraulic active suspension as described in Embodiment 2 of the present invention. Detailed Implementation

[0022] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0023] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations of the present invention.

[0024] Where there is no conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0025] With the increasing popularity of intelligent vehicles, especially hybrid and pure electric vehicles, users' demands for vehicle handling and comfort are becoming more prominent. Handling stability is particularly important when making emergency lane changes at high speeds. When a vehicle tilts, especially at a large angle, it can lead to a lack of driver confidence, anxiety, and even safety risks and inconvenience at high speeds, negatively impacting the driving experience.

[0026] To balance vertical comfort, current technologies typically design suspension stiffness at a moderate level. However, when the vehicle rolls, the suspension's contribution to handling stability is insufficient, failing to simultaneously achieve both comfort and handling stability. While a dual-chamber air suspension with two-stage adjustable stiffness addresses roll conditions, the non-linear adjustment of these two stages means that when the vehicle rolls and the second stage stiffness is not triggered, or when the roll acceleration is significant after triggering the second stage stiffness, handling stability remains poor. Drivers can only improve confidence by reducing speed, and this can even pose safety risks in special avoidance situations. Although handling stability is improved compared to traditional suspensions, the non-linear two-stage height adjustment negatively impacts the driving experience.

[0027] Therefore, there is an urgent need for a method and system that can proactively intervene in vehicle control, generate different lateral support stiffnesses according to different roll accelerations under roll conditions through precise calculations and intelligent decision-making, and ensure better roll control.

[0028] Example 1 In one or more embodiments, a control method for suppressing vehicle roll based on hydraulic active suspension is disclosed, which is applicable to mid-range family cars. The chip computing power is: main frequency not less than 200MHz, computing power not less than 300DMIPS, and storage capacity: program storage (Flash) ≥5MB; running memory (RAM) ≥2M.

[0029] The hydraulic active suspension system includes a controller, sensor units, actuators, and shock absorbers. The sensor units are electrically connected to the controller, and the actuators are also electrically connected to the controller. This method actively intervenes to control the vehicle under roll conditions by monitoring vehicle dynamic signals in real time, achieving precise suppression of the roll angle.

[0030] Specifically, the sensor unit includes a vehicle speed sensor, a steering wheel angle sensor, a steering wheel angle acceleration sensor, and a height sensor. The vehicle speed sensor acquires the vehicle's speed signal in real time and is typically installed near the wheels or on the transmission output shaft. The steering wheel angle sensor acquires the steering wheel angle signal and is installed on the steering column. The steering wheel angle acceleration sensor acquires the rate of change of the steering wheel angle, which can be obtained by differentiating the angle signal or by direct measurement using a separate sensor. Height sensors are located on the left and right sides of the vehicle body to measure the vehicle's height relative to the wheels in real time; these are typically laser or ultrasonic sensors installed at the connection between the suspension and the body.

[0031] The controller is a chassis domain controller, such as Figure 3As shown, it features a high-performance microprocessor, memory, communication interfaces, and an in-vehicle Ethernet interface. The processor has a main frequency of no less than 200MHz, a computing power of no less than 300DMIPS, supports ASIL-D functional safety level, and has interface features such as high-precision ADC, multi-channel CAN-FD, and 100M Ethernet. The memory includes a program storage area and a data storage area. The program storage area is no less than 5MB, used to store control algorithms and system programs; the data storage area is no less than 2MB, used to store a mapping table of target values ​​for vehicle speed, steering wheel angle, and motor speed, as well as historical data. This mapping table is obtained through real-vehicle calibration and contains the optimal target values ​​for motor speed and solenoid valve current under different combinations of vehicle speed and steering wheel angle. The communication interface is a CAN / CAN FD / LIN bus interface, used to communicate with nodes such as the HMI controller, steering controller, and brake controller inside the vehicle to acquire data and send control commands. The in-vehicle Ethernet interface is used for high-speed data exchange with the Advanced Driver Assistance System (ADAS) domain and the infotainment system domain.

[0032] The controller communicates with various sensors and actuators via a CAN bus. The CAN bus communication rate is 500kbps or 1Mbps, ensuring real-time and reliable data transmission. The controller integrates a feedforward calculation unit and a closed-loop correction unit. The feedforward calculation unit calculates the actuator target value for the next moment based on the steering wheel angle acceleration signal, while the closed-loop correction unit corrects the target value in real time based on the actual vehicle height difference fed back by the height sensor.

[0033] The actuators include a hydraulic pump motor and solenoid valves, respectively mounted on the shock absorbers on the left and right sides of the vehicle body. The hydraulic pump motor's speed is adjustable from 0 to 6000 rpm, and the oil supply flow rate of the hydraulic pump is regulated by controlling the motor speed. The solenoid valve controls the valve spool opening by adjusting the drive current, thereby regulating the oil flow rate in the hydraulic chamber of the shock absorber; the drive current ranges from 0 to 2A. The hydraulic pump and solenoid valves are connected to the corresponding shock absorbers via hydraulic lines, which use high-pressure oil-resistant rubber hoses or rigid metal pipes, with a working pressure up to 20 MPa.

[0034] The shock absorber is a hydraulic type, consisting of a piston, piston rod, cylinder, and hydraulic chamber. When the hydraulic pump supplies oil to the shock absorber, hydraulic oil enters the hydraulic chamber, pushing the piston upward and lifting the vehicle body. When the solenoid valve opens wider, oil flows out of the hydraulic chamber, causing the piston to move downward and lowering the vehicle body. By coordinating the actions of the hydraulic pumps and solenoid valves on both sides, differential adjustment of the height of the left and right sides of the vehicle body is achieved, thereby suppressing vehicle roll.

[0035] When a vehicle is about to tilt, this invention automatically activates the roll suppression control function. This involves dynamically calculating and executing a stiffness adjustment signal to suppress roll, based on vehicle dynamic information recognition. The actuator adjusts the stiffness, providing active support on the outer side of the roll to increase stiffness, and active downforce on the inner side to decrease stiffness, thus maximally suppressing roll and ensuring safer driving. This completely eliminates user anxiety about handling stability, improves user confidence in high-speed driving, and enhances driving safety. Figure 1 - Figure 2 As shown, the control method includes the following steps: Step S101: Obtain vehicle speed, steering wheel angle and angular acceleration signals. When the vehicle speed signal reaches a preset vehicle speed threshold and the steering wheel angle signal reaches a preset angular acceleration threshold, perform roll suppression.

[0036] In one implementation, the controller reads signals from the vehicle speed sensor, steering wheel angle sensor, steering wheel angle acceleration sensor, and height sensor in real time via the CAN bus.

[0037] The vehicle speed sensor outputs a vehicle speed signal V that is an analog or digital signal in the range of 0 to 250 km / h. The controller converts the analog signal into a digital signal through the ADC module, or directly reads the digital signal through the CAN bus. The sampling frequency is 100 Hz.

[0038] The steering wheel angle sensor outputs a steering angle signal α, which is a digital signal in the range of -720° to +720°. The controller reads this signal through the CAN bus, with a sampling frequency of 100Hz and a resolution of 0.1°.

[0039] The steering wheel angle acceleration sensor outputs a steering angle acceleration signal β, which is a digital signal in the range of -500° / s² to +500° / s². The controller reads this signal through the CAN bus or calculates it by differentiating the steering angle signal α. The sampling frequency is 100Hz.

[0040] Height sensors are located on the left and right sides of the vehicle, respectively, and output the height H of the left side of the vehicle. L and the height H of the right side of the vehicle R The signal range is -100mm to +100mm, the resolution is 0.5mm, and the controller reads the signal through the CAN bus at a sampling frequency of 100Hz.

[0041] The controller verifies the validity of the read signals: each signal is filtered using a first-order low-pass filter (cutoff frequency 10Hz) to remove high-frequency noise; over-limit signals are protected, and when a signal exceeds the range, it is determined to be an invalid signal, and the valid value of the previous cycle or the corresponding default value is used. The default values ​​are: vehicle speed 0km / h, turning angle 0°, turning acceleration 0° / s², and height 0mm.

[0042] Furthermore, a dual-condition and logical approach is used to determine the roll condition: When the vehicle speed signal V ≥ preset vehicle speed threshold V0 and the steering wheel angle signal |α| ≥ preset steering angle threshold α0, the vehicle is determined to be in a roll condition, and the roll suppression function is activated. The controller sends an enable command to the hydraulic pump motor and solenoid valve via the CAN bus. The enable command includes a function activation flag, a target execution timestamp, and a security check code. After receiving the enable command, the hydraulic pump motor and solenoid valve enter a standby state. In this embodiment, V0 = 40 km / h, and α0 = 30°.

[0043] Step S102: Perform feedforward judgment for roll suppression based on the steering wheel angle acceleration signal, and obtain the target values ​​of motor speed and solenoid valve current by combining vehicle speed and steering wheel angle signals.

[0044] Based on the steering wheel angle acceleration signal β, a feedforward judgment is made to generate the changing trend of the roll suppression target: When β > 0, it indicates that the steering wheel is accelerating to the right, and the vehicle is predicted to tilt to the right; when β < 0, it indicates that the steering wheel is accelerating to the left, and the vehicle is predicted to tilt to the left.

[0045] As one implementation method, based on the current vehicle speed signal, steering wheel angle and angular acceleration signal, the pre-stored Mapping table in the memory is queried to obtain the target value of motor speed and target value of solenoid valve current under the current operating conditions.

[0046] Specifically, the angular acceleration signal, along with the vehicle speed and steering wheel angle, are used as input parameters. The pre-stored multi-dimensional mapping table in the memory is queried to directly obtain the target values ​​of the motor speed and solenoid valve current for the next moment.

[0047] The multidimensional mapping table is obtained through real vehicle calibration. Its input parameters include vehicle speed, steering wheel angle and steering wheel angle acceleration, and the output is the actuator's action target (motor speed target value and solenoid valve current target value).

[0048] It should be understood that the solenoid valve is a throttle valve responsible for adjusting the damping force. It primarily works in conjunction with the shock absorber. During compression or recovery, it generates different damping forces by adjusting the size of the throttle orifice (i.e., the current magnitude) (the larger the orifice, the smaller the damping force). The motor speed is responsible for stiffness adjustment, providing the main force. The oil pump provides different pressures to the upper and lower chambers of the shock absorber by adjusting the oil supply; the pressure magnitude also determines the magnitude of the main force. Preferably, the solenoid valve always operates during roll suppression, while the motor provides the main force during greater roll. The mapping table presets target values ​​for various operating conditions calibrated on the actual vehicle.

[0049] Since the steering acceleration signal β reflects the changing trend of the steering wheel angle, incorporating it into the input dimension of the mapping table allows the lookup results to reflect the actuator requirements at the next moment in advance. Compared with the lookup method that only uses vehicle speed and steering angle as input, the response speed is faster and the roll suppression effect is better.

[0050] Furthermore, the target value of the instruction to be issued is obtained, and the target instruction is issued to the executor.

[0051] The target values ​​for motor speed and solenoid valve current output from the mapping table are used as the basic target values, and then corrected by combining the feedforward calculation results.

[0052] Step S103: Compare the actual height difference between the left and right sides of the vehicle with the preset target height difference; when the actual height difference exceeds the preset range of the target height difference, correct the target value of the motor speed and the target value of the solenoid valve current in real time.

[0053] Step S1031: Obtain the actual height difference between the left and right sides of the vehicle body using a height sensor, and compare it with the preset target height difference.

[0054] The left-side height sensor measures the left-side vehicle height H. L The right-side height sensor measures the right-side vehicle height H. R Calculate the actual vehicle body height difference:

[0055] in, This represents the actual vehicle height difference. When... When the left side of the vehicle is higher than the right side, it indicates that the vehicle is tilting to the right; when This indicates that the right side of the vehicle is higher than the left, causing the vehicle to tilt to the left. The actual difference in vehicle height... Difference from the preset target vehicle height Compare the measurements and calculate the height deviation:

[0056] in, For height deviation; This parameter is typically set to a constant value close to 0mm, with 0mm being optimal, indicating that the vehicle body maintains a level posture. The height deviation is then compared to a preset deviation range of ±5mm: when | When | ≤ 5mm, the vehicle height difference is within the allowable range and no correction is needed; when | If the height difference is greater than 5mm, the vehicle height difference exceeds the allowable range, and a correction will be performed.

[0057] Step S1032: When the actual vehicle height difference exceeds the preset deviation range, the current target values ​​of motor speed and solenoid valve current are corrected according to the target values ​​of motor speed and solenoid valve current at the next moment.

[0058] The correction of target commands during actual vehicle movement includes functional safety verification to prevent the direction of the main force from reversing, which could lead to safety issues; and target value verification and correction. To overcome the limitations of multidimensional table calibration in mapping, closed-loop correction of the target values ​​is required.

[0059] First, the functional safety verification includes: calculating the height difference between the left and right sides (distinguishing between positive and negative) based on the height sensor signal of the current vehicle status, comparing the target active force direction based on the set target active force direction, and executing the action when the upward target active force and the lower posture side are on the same side, or the downward target active force and the higher posture side are on the same side, and stopping the action execution first when they are not on the same side for safety reasons.

[0060] Furthermore, the target value verification and correction are specifically as follows: Based on the vehicle height sensor signal, the height difference between the left and right vehicles is obtained, and the current height difference is compared with the target height difference. When the actual height difference is greater than the target height difference range, the system corrects the current motor target speed to improve accuracy. That is, the target is corrected in real time through height closed loop, resulting in a more precise control effect.

[0061] When the actual vehicle height difference exceeds the preset deviation range, according to the height deviation amount The current motor speed correction is performed by looking up a table: By establishing the calibrated correspondence between height deviation and motor speed, the correction amount for motor speed under the current height deviation is obtained. The correction amount is then added to the target value to obtain the current motor speed value.

[0062] For example, when the height deviation is 5mm, the speed is increased by 200rpm; when the height deviation is 10mm, the speed is increased by 400rpm.

[0063] Preferably, when the motor speed exceeds a certain threshold, a new solenoid valve current is obtained through a mapping table between the motor speed and the solenoid valve current. This embodiment considers that the solenoid valve may leak pressure; therefore, when a large main power is required, the solenoid valve needs to be adjusted to reduce throttling, decrease leakage, and increase main power.

[0064] In this step, the target values ​​for motor speed and solenoid valve current are initially set as the current motor speed and solenoid valve current. When the above height difference judgment is met, the current motor speed and solenoid valve current are corrected. The corrected motor speed and solenoid valve current are then used as the current motor speed and solenoid valve current for execution. This process is repeated until the height difference is no greater than the target height difference range, and then the process returns to step S102.

[0065] Because there is a certain delay in the execution of the actuator, in order to improve the functional effect, this embodiment selects vehicle speed, steering wheel angle, and steering wheel angle acceleration as the judgment conditions for triggering the function, instead of selecting the IMU's lateral acceleration signal as the input signal for calculation. Moreover, the IMU's lateral acceleration signal has a large delay. When the signal is input, the vehicle's tilt has already occurred. When the actuator is executed, the effect is already significantly delayed, which is not conducive to the overall vehicle handling stability.

[0066] Step S104: Based on the corrected target values ​​of motor speed and solenoid valve current, control the vehicle tilt within the target range in real time, and repeat the above process.

[0067] When the roll suppression function is activated, steps S102 and S103 are repeated at a preset frequency to implement closed-loop control until S101 no longer provides a function activation signal.

[0068] The actual state of the vehicle may change suddenly (such as emergency avoidance). This embodiment can continuously correct the target through closed-loop feedback to ensure the driving stability of the vehicle.

[0069] As an example, the steps to implement the above technical solution are as follows: A car traveling on a highway notices a vehicle ahead braking suddenly in its lane. Due to the short following distance, braking may not be enough to avoid a collision, necessitating an emergency turn and lane change to avoid the collision. At this point, the vehicle faces a significant risk of tilting and overturning. The system determines an initial threshold based on real-time road conditions (vehicle speed, steering wheel angle), and then activates the roll suppression function based on the determination result.

[0070] Once activated, the motor speed and solenoid valve current required to maintain the vehicle's tilt within the target range are calculated, and commands are sent to the actuators. The actuators then perform actions, generating active support force on the outer side of the tilt and providing a pulling force on the inner side to suppress unilateral rise, thus keeping the vehicle within the target tilt range.

[0071] During a turn, the system repeatedly executes the signal, calculates it, corrects it in a closed loop, and then executes it, adjusting the target in real time to keep the vehicle in a stable state and safely perform emergency turns to avoid obstacles.

[0072] Finally, the vehicle completed the lane change and resumed straight driving. The steering wheel angle signal did not meet the function activation threshold, so the function execution ended.

[0073] Example 2 In one or more embodiments, a control method for suppressing vehicle roll based on hydraulic active suspension is disclosed, which is suitable for high-end handling models. It requires a chip with more powerful computing power, with a main frequency of not less than 200MHz and a computing power of not less than 1000DMIPS. The synchronous controller has a large storage capacity, with program storage (Flash) ≥500MB and running memory (RAM) ≥20M.

[0074] The hydraulic active suspension system includes a controller, sensor units, actuators, and shock absorbers. The sensor units are electrically connected to the controller, and the actuators are also electrically connected to the controller. This method actively intervenes to control the vehicle under roll conditions by monitoring vehicle dynamic signals in real time, achieving precise suppression of the roll angle.

[0075] Specifically, the sensor unit includes a vehicle speed sensor, a steering wheel angle sensor, a steering wheel angle acceleration sensor, and a height sensor. The vehicle speed sensor acquires the vehicle's speed signal in real time and is typically installed near the wheels or on the transmission output shaft. The steering wheel angle sensor acquires the steering wheel angle signal and is installed on the steering column. The steering wheel angle acceleration sensor acquires the rate of change of the steering wheel angle, which can be obtained by differentiating the angle signal or by direct measurement using a separate sensor. Height sensors are located on the left and right sides of the vehicle body to measure the vehicle's height relative to the wheels in real time; these are typically laser or ultrasonic sensors installed at the connection between the suspension and the body.

[0076] The controller is a chassis domain controller, featuring a high-performance microprocessor, memory, communication interfaces, and an in-vehicle Ethernet interface. The processor has a clock speed of at least 200MHz, a computing power of at least 300DMIPS, supports ASIL-D functional safety level, and features high-precision ADC, multi-channel CAN-FD, and 100M Ethernet interfaces. The memory includes a program storage area and a data storage area. The program storage area is at least 5MB, used to store control algorithms and system programs; the data storage area is at least 2MB, used to store a mapping table of vehicle speed, steering wheel angle, and target motor speed values, as well as historical data. This mapping table is obtained through real-vehicle calibration and contains optimal target motor speed values ​​and solenoid valve current values ​​for different combinations of vehicle speed and steering wheel angle. The communication interface is a CAN / CAN FD / LIN bus interface, used to communicate with internal vehicle nodes such as the HMI controller, steering controller, and brake controller to acquire data and send control commands. The in-vehicle Ethernet interface is used for high-speed data exchange with the Advanced Driver Assistance System (ADAS) domain and infotainment system domain.

[0077] The controller communicates with various sensors and actuators via a CAN bus. The CAN bus communication rate is 500kbps or 1Mbps, ensuring real-time and reliable data transmission. The controller integrates a feedforward calculation unit and a closed-loop correction unit. The feedforward calculation unit calculates the actuator target value for the next moment based on the steering wheel angle acceleration signal, while the closed-loop correction unit corrects the target value in real time based on the actual vehicle height difference fed back by the height sensor.

[0078] The actuators include a hydraulic pump motor and solenoid valves, respectively mounted on the shock absorbers on the left and right sides of the vehicle body. The hydraulic pump motor's speed is adjustable from 0 to 6000 rpm, and the oil supply flow rate of the hydraulic pump is regulated by controlling the motor speed. The solenoid valve controls the valve spool opening by adjusting the drive current, thereby regulating the oil flow rate in the hydraulic chamber of the shock absorber; the drive current ranges from 0 to 2A. The hydraulic pump and solenoid valves are connected to the corresponding shock absorbers via hydraulic lines, which use high-pressure oil-resistant rubber hoses or rigid metal pipes, with a working pressure up to 20 MPa.

[0079] The shock absorber is a hydraulic type, consisting of a piston, piston rod, cylinder, and hydraulic chamber. When the hydraulic pump supplies oil to the shock absorber, hydraulic oil enters the hydraulic chamber, pushing the piston upward and lifting the vehicle body. When the solenoid valve opens wider, oil flows out of the hydraulic chamber, causing the piston to move downward and lowering the vehicle body. By coordinating the actions of the hydraulic pumps and solenoid valves on both sides, differential adjustment of the height of the left and right sides of the vehicle body is achieved, thereby suppressing vehicle roll.

[0080] When a vehicle is about to tilt, this invention can automatically activate the roll suppression control function. Specifically, by identifying vehicle dynamic information, it dynamically calculates and executes a stiffness adjustment signal to suppress vehicle roll. The actuator then adjusts the stiffness, providing active support on the outer side of the roll to increase stiffness, and providing active downforce on the inner side to reduce stiffness, thus maximally suppressing vehicle roll and ensuring safer driving. This completely eliminates user anxiety about handling stability, improves user confidence in high-speed driving, and enhances driving safety. The control method includes the following steps: Step S201: Obtain vehicle speed, steering wheel angle and steering acceleration signals. When the vehicle speed signal reaches a preset vehicle speed threshold and the steering wheel angle signal reaches a preset steering angle threshold, perform roll suppression.

[0081] In one implementation, the controller reads signals from the vehicle speed sensor, steering wheel angle sensor, steering wheel angle acceleration sensor, and height sensor in real time via the CAN bus.

[0082] The vehicle speed sensor outputs a vehicle speed signal V that is an analog or digital signal in the range of 0 to 250 km / h. The controller converts the analog signal into a digital signal through the ADC module, or directly reads the digital signal through the CAN bus. The sampling frequency is 100 Hz.

[0083] The steering wheel angle sensor outputs a steering angle signal α, which is a digital signal in the range of -720° to +720°. The controller reads this signal through the CAN bus, with a sampling frequency of 100Hz and a resolution of 0.1°.

[0084] The steering wheel angle acceleration sensor outputs a steering angle acceleration signal β, which is a digital signal in the range of -500° / s² to +500° / s². The controller reads this signal through the CAN bus or calculates it by differentiating the steering angle signal α. The sampling frequency is 100Hz.

[0085] Height sensors are located on the left and right sides of the vehicle, respectively, and output the height H of the left side of the vehicle. L and the height H of the right side of the vehicle R The signal range is -100mm to +100mm, the resolution is 0.5mm, and the controller reads the signal through the CAN bus at a sampling frequency of 100Hz.

[0086] The controller verifies the validity of the read signals: each signal is filtered using a first-order low-pass filter (cutoff frequency 10Hz) to remove high-frequency noise; over-limit signals are protected, and when a signal exceeds the range, it is determined to be an invalid signal, and the valid value of the previous cycle or the corresponding default value is used. The default values ​​are: vehicle speed 0km / h, turning angle 0°, turning acceleration 0° / s², and height 0mm.

[0087] Furthermore, a dual-condition and logical approach is used to determine the roll condition: When the vehicle speed signal V ≥ preset vehicle speed threshold V0 and the steering wheel angle signal |α| ≥ preset steering angle threshold α0, the vehicle is determined to be in a roll condition, and the roll suppression function is activated. The controller sends an enable command to the hydraulic pump motor and solenoid valve via the CAN bus. The enable command includes a function activation flag, a target execution timestamp, and a security check code. After receiving the enable command, the hydraulic pump motor and solenoid valve enter a standby state. In this embodiment, V0 = 40 km / h, and α0 = 30°.

[0088] Step S202: Perform feedforward judgment for roll suppression based on the steering wheel angle acceleration signal, and obtain the target values ​​of motor speed and solenoid valve current by combining vehicle speed and steering wheel angle signals.

[0089] Based on the steering wheel angle acceleration signal β, a feedforward judgment is made to generate the changing trend of the roll suppression target: When β > 0, it indicates that the steering wheel is accelerating to the right, and the vehicle is predicted to tilt to the right; when β < 0, it indicates that the steering wheel is accelerating to the left, and the vehicle is predicted to tilt to the left.

[0090] As one implementation method, a vehicle dynamics calculation model is used, with vehicle speed, steering wheel angle and steering wheel angle acceleration signals as input, to obtain the target values ​​of motor speed and solenoid valve current.

[0091] As one implementation method, the target lateral acceleration is obtained by calculating vehicle dynamic parameters in real time, including vehicle speed, steering wheel angle and steering wheel angular acceleration, and the target lateral acceleration is converted into the actuator target value as an intermediate quantity.

[0092] Specifically, the current vehicle speed, steering wheel angle, and angular acceleration are read, and the actuator target value for the next moment is obtained through the following dynamic calculation process: The first step is to predict the steering wheel angle for the next control cycle. :

[0093] in, The current steering wheel angle; The current angular velocity is obtained by differentiating the angular signal; Δt represents the current steering wheel angle acceleration; Δt is the control period, which in this embodiment is Δt=10ms.

[0094] The second step is to calculate the target's lateral acceleration at the next moment:

[0095] in, Let be the turning radius, and Where g is the acceleration due to gravity, L is the wheelbase, and i is the steering ratio. The target lateral acceleration at the next moment reflects the theoretically expected level of lateral acceleration of the vehicle at the current speed and predicted steering angle, and is the core intermediate output of the dynamics calculation model.

[0096] The third step is to calculate the roll moment:

[0097] Where m is the vehicle's curb weight and h is the height of the center of gravity. The roll moment reflects the rollover moment generated by lateral acceleration on the vehicle body.

[0098] Step 4: Calculate the required active support force:

[0099] Where B is the wheelbase and B / 2 is the lever arm. The active support force is the upward active support force that the hydraulic pump on the outer side of the tilting mechanism needs to provide, and it is also the downward active pressure that the solenoid valve on the inner side of the tilting mechanism needs to release.

[0100] The fifth step involves retrieving the target values ​​for the motor speed and solenoid valve current at the next moment using a pre-defined two-dimensional mapping table of active support force and actuator target values. This mapping table, obtained through hydraulic system characteristic calibration, reflects the optimal combination of hydraulic pump motor speed and solenoid valve current under different active support force requirements.

[0101] In this embodiment, the target lateral acceleration is calculated in real time through a vehicle dynamics calculation model. The required active support force can be accurately calculated based on the actual dynamic parameters of the vehicle, adapting to dynamic changes under different load conditions, such as full load and no load. There is no need to calibrate the mapping table separately for each load condition, making it more accurate.

[0102] Furthermore, the target value of the instruction to be issued is obtained, and the target instruction is issued to the executor.

[0103] The target values ​​for motor speed and solenoid valve current output from the mapping table are used as the basic target values, and then corrected by combining the feedforward calculation results.

[0104] Step S203: Compare the actual height difference between the left and right sides of the vehicle with the preset target height difference; when the actual height difference exceeds the preset range of the target height difference, correct the target value of the motor speed and the target value of the solenoid valve current in real time.

[0105] Step S2031: Obtain the actual height difference between the left and right sides of the vehicle body using a height sensor, and compare it with the preset target height difference.

[0106] The left-side height sensor measures the left-side vehicle height H. L The right-side height sensor measures the right-side vehicle height H. R Calculate the actual vehicle body height difference:

[0107] in, This represents the actual vehicle height difference. When... When the left side of the vehicle is higher than the right side, it indicates that the vehicle is tilting to the right; when This indicates that the right side of the vehicle is higher than the left, causing the vehicle to tilt to the left. The actual difference in vehicle height... Difference from the preset target vehicle height Compare the measurements and calculate the height deviation:

[0108] in, For height deviation; This parameter is typically set to a constant value close to 0mm, with 0mm being optimal, indicating that the vehicle body maintains a level posture. The height deviation is then compared to a preset deviation range of ±5mm: when | When | ≤ 5mm, the vehicle height difference is within the allowable range and no correction is needed; when | If the height difference is greater than 5mm, the vehicle height difference exceeds the allowable range, and a correction will be performed.

[0109] Step S2032: When the actual vehicle height difference exceeds the preset deviation range, the current target values ​​of motor speed and solenoid valve current are corrected according to the target values ​​of motor speed and solenoid valve current at the next moment.

[0110] The correction of target commands during actual vehicle movement includes functional safety verification to prevent the direction of the main force from reversing, which could lead to safety issues; and target value verification and correction. To address the discrepancy between the calculation model and reality, a closed-loop correction of the target value is required.

[0111] First, the functional safety verification includes: calculating the height difference between the left and right sides (distinguishing between positive and negative) based on the height sensor signal of the current vehicle status, comparing the target active force direction based on the set target active force direction, and executing the action when the upward target active force and the lower posture side are on the same side, or the downward target active force and the higher posture side are on the same side, and stopping the action execution first when they are not on the same side for safety reasons.

[0112] Furthermore, the target value verification and correction are specifically as follows: Based on the vehicle height sensor signal, the height difference between the left and right vehicles is obtained, and the current height difference is compared with the target height difference. When the actual height difference is greater than the target height difference range, the system corrects the current motor target speed to improve accuracy. That is, the target is corrected in real time through height closed loop, resulting in a more precise control effect.

[0113] When the actual vehicle height difference exceeds the preset deviation range, according to the height deviation amount The current motor speed correction is performed by looking up a table: By establishing the calibrated correspondence between height deviation and motor speed, the correction amount for motor speed under the current height deviation is obtained. The correction amount is then added to the target value to obtain the current motor speed value.

[0114] For example, when the height deviation is 5mm, the speed is increased by 200rpm; when the height deviation is 10mm, the speed is increased by 400rpm.

[0115] Preferably, when the motor speed exceeds a certain threshold, a new solenoid valve current is obtained through a mapping table between the motor speed and the solenoid valve current. This embodiment considers that the solenoid valve may leak pressure; therefore, when a large main power is required, the solenoid valve needs to be adjusted to reduce throttling, decrease leakage, and increase main power.

[0116] In this step, the target values ​​for motor speed and solenoid valve current are initially set as the current motor speed and solenoid valve current. When the above height difference judgment is met, the current motor speed and solenoid valve current are corrected. The corrected motor speed and solenoid valve current are then used as the current motor speed and solenoid valve current for execution. This process is repeated until the height difference is no greater than the target height difference range, and then the process returns to step S202.

[0117] Because there is a certain delay in the execution of the actuator, in order to improve the functional effect, this embodiment selects vehicle speed, steering wheel angle, and steering wheel angle acceleration as the judgment conditions for triggering the function, instead of selecting the IMU's lateral acceleration signal as the input signal for calculation. Moreover, the IMU's lateral acceleration signal has a large delay. When the signal is input, the vehicle's tilt has already occurred. When the actuator is executed, the effect is already significantly delayed, which is not conducive to the overall vehicle handling stability.

[0118] Step S204: Based on the corrected target values ​​for motor speed and solenoid valve current, control the vehicle tilt within the target range in real time, and repeat the above process.

[0119] When the roll suppression function is activated, steps S202 and S203 are repeated at a preset frequency to implement closed-loop control until S201 no longer provides a function activation signal.

[0120] The actual state of the vehicle may change suddenly (such as emergency avoidance). This embodiment can continuously correct the target through closed-loop feedback to ensure the driving stability of the vehicle.

[0121] As an example, the steps to implement the above technical solution are as follows: A car traveling on a highway notices a vehicle ahead braking suddenly in its lane. Due to the short following distance, braking may not be enough to avoid a collision, necessitating an emergency turn and lane change to avoid the collision. At this point, the vehicle faces a significant risk of tilting and overturning. The system determines an initial threshold based on real-time road conditions (vehicle speed, steering wheel angle), and then activates the roll suppression function based on the determination result.

[0122] Once activated, the motor speed and solenoid valve current required to maintain the vehicle's tilt within the target range are calculated, and commands are sent to the actuators. The actuators then perform actions, generating active support force on the outer side of the tilt and providing a pulling force on the inner side to suppress unilateral rise, thus keeping the vehicle within the target tilt range.

[0123] During a turn, the system repeatedly executes the signal, calculates it, corrects it in a closed loop, and then executes it, adjusting the target in real time to keep the vehicle in a stable state and safely perform emergency turns to avoid obstacles.

[0124] Finally, the vehicle completed the lane change and resumed straight driving. The steering wheel angle signal did not meet the function activation threshold, so the function execution ended.

[0125] Example 3 In one or more embodiments, a control system 300 based on hydraulic active suspension for vehicle roll suppression is disclosed, such as... Figure 4 As shown, it specifically includes: The data acquisition module 301 is used to acquire vehicle speed, steering wheel angle and angular acceleration signals. When the vehicle speed signal reaches a preset vehicle speed threshold and the steering wheel angle signal reaches a preset angle threshold, roll suppression is performed. The feedforward judgment module 302 is used to make feedforward judgments for roll suppression based on the steering wheel angle acceleration signal, and to obtain the target values ​​of motor speed and solenoid valve current by combining the vehicle speed and steering wheel angle signals, and then execute the target values. The target correction module 303 is used to compare the actual height difference between the left and right sides of the vehicle with the preset target height difference; when the actual height difference exceeds the preset range of the target height difference, the target value of the motor speed and the target value of the solenoid valve current are corrected in real time. The loop optimization module 304 is used to control the vehicle tilt within the target range in real time based on the corrected target values ​​of motor speed and solenoid valve current, and repeat the above process in a loop.

[0126] Specifically, the data acquisition module 301 acquires vehicle speed, steering wheel angle and steering acceleration signals. When the vehicle speed signal reaches a preset vehicle speed threshold and the steering wheel angle signal reaches a preset steering angle threshold, roll suppression is performed.

[0127] In one implementation, the controller reads signals from the vehicle speed sensor, steering wheel angle sensor, steering wheel angle acceleration sensor, and height sensor in real time via the CAN bus.

[0128] The vehicle speed sensor outputs a vehicle speed signal V that is an analog or digital signal in the range of 0 to 250 km / h. The controller converts the analog signal into a digital signal through the ADC module, or directly reads the digital signal through the CAN bus. The sampling frequency is 100 Hz.

[0129] The steering wheel angle sensor outputs a steering angle signal α, which is a digital signal in the range of -720° to +720°. The controller reads this signal through the CAN bus, with a sampling frequency of 100Hz and a resolution of 0.1°.

[0130] The steering wheel angle acceleration sensor outputs a steering angle acceleration signal β, which is a digital signal in the range of -500° / s² to +500° / s². The controller reads this signal through the CAN bus or calculates it by differentiating the steering angle signal α. The sampling frequency is 100Hz.

[0131] Height sensors are located on the left and right sides of the vehicle, respectively, and output the height H of the left side of the vehicle. L and the height H of the right side of the vehicle R The signal range is -100mm to +100mm, the resolution is 0.5mm, and the controller reads the signal through the CAN bus at a sampling frequency of 100Hz.

[0132] The controller verifies the validity of the read signals: each signal is filtered using a first-order low-pass filter (cutoff frequency 10Hz) to remove high-frequency noise; over-limit signals are protected, and when a signal exceeds the range, it is determined to be an invalid signal, and the valid value of the previous cycle or the corresponding default value is used. The default values ​​are: vehicle speed 0km / h, turning angle 0°, turning acceleration 0° / s², and height 0mm.

[0133] Furthermore, a dual-condition and logical approach is used to determine the roll condition: When the vehicle speed signal V ≥ preset vehicle speed threshold V0 and the steering wheel angle signal |α| ≥ preset steering angle threshold α0, the vehicle is determined to be in a roll condition, and the roll suppression function is activated. The controller sends an enable command to the hydraulic pump motor and solenoid valve via the CAN bus. The enable command includes a function activation flag, a target execution timestamp, and a security check code. After receiving the enable command, the hydraulic pump motor and solenoid valve enter a standby state. In this embodiment, V0 = 40 km / h, and α0 = 30°.

[0134] Feedforward judgment module 302: performs feedforward judgment on roll suppression based on steering wheel angle acceleration signal, and obtains target values ​​for motor speed and solenoid valve current by combining vehicle speed and steering wheel angle signals.

[0135] Based on the steering wheel angle acceleration signal β, a feedforward judgment is made to generate the changing trend of the roll suppression target: When β > 0, it indicates that the steering wheel is accelerating to the right, and the vehicle is predicted to tilt to the right; when β < 0, it indicates that the steering wheel is accelerating to the left, and the vehicle is predicted to tilt to the left.

[0136] As one implementation method, based on the current vehicle speed signal, steering wheel angle and angular acceleration signal, the pre-stored Mapping table in the memory is queried to obtain the target value of motor speed and target value of solenoid valve current under the current operating conditions.

[0137] Specifically, the angular acceleration signal, along with the vehicle speed and steering wheel angle, are used as input parameters. The pre-stored multi-dimensional mapping table in the memory is queried to directly obtain the target values ​​of the motor speed and solenoid valve current for the next moment.

[0138] The multidimensional mapping table is obtained through real vehicle calibration. Its input parameters include vehicle speed, steering wheel angle and steering wheel angle acceleration, and the output is the actuator's action target (motor speed target value and solenoid valve current target value).

[0139] It should be understood that the solenoid valve is a throttle valve responsible for adjusting the damping force. It primarily works in conjunction with the shock absorber. During compression or recovery, it generates different damping forces by adjusting the size of the throttle orifice (i.e., the current magnitude) (the larger the orifice, the smaller the damping force). The motor speed is responsible for stiffness adjustment, providing the main force. The oil pump provides different pressures to the upper and lower chambers of the shock absorber by adjusting the oil supply; the pressure magnitude also determines the magnitude of the main force. Preferably, the solenoid valve always operates during roll suppression, while the motor provides the main force during greater roll. The mapping table presets target values ​​for various operating conditions calibrated on the actual vehicle.

[0140] Since the steering acceleration signal β reflects the changing trend of the steering wheel angle, incorporating it into the input dimension of the mapping table allows the lookup results to reflect the actuator requirements at the next moment in advance. Compared with the lookup method that only uses vehicle speed and steering angle as input, the response speed is faster and the roll suppression effect is better.

[0141] Another implementation method uses a vehicle dynamics calculation model, with vehicle speed, steering wheel angle and steering wheel angle acceleration signals as inputs, to obtain the target values ​​of motor speed and solenoid valve current.

[0142] By calculating vehicle dynamics parameters in real time, including vehicle speed, steering wheel angle, and steering wheel angle acceleration, the target lateral acceleration is obtained, and the target lateral acceleration is converted into the actuator target value as an intermediate quantity.

[0143] Specifically, the current vehicle speed, steering wheel angle, and angular acceleration are read, and the actuator target value for the next moment is obtained through the following dynamic calculation process: The first step is to predict the steering wheel angle for the next control cycle. :

[0144] in, The current steering wheel angle; The current angular velocity is obtained by differentiating the angular signal; Δt represents the current steering wheel angle acceleration; Δt is the control period, which in this embodiment is Δt=10ms.

[0145] The second step is to calculate the target's lateral acceleration at the next moment:

[0146] in, Let be the turning radius, and Where g is the acceleration due to gravity, L is the wheelbase, and i is the steering ratio. The target lateral acceleration at the next moment reflects the theoretically expected level of lateral acceleration of the vehicle at the current speed and predicted steering angle, and is the core intermediate output of the dynamics calculation model.

[0147] The third step is to calculate the roll moment:

[0148] Where m is the vehicle's curb weight and h is the height of the center of gravity. The roll moment reflects the rollover moment generated by lateral acceleration on the vehicle body.

[0149] Step 4: Calculate the required active support force:

[0150] Where B is the wheelbase and B / 2 is the lever arm. The active support force is the upward active support force that the hydraulic pump on the outer side of the tilting mechanism needs to provide, and it is also the downward active pressure that the solenoid valve on the inner side of the tilting mechanism needs to release.

[0151] The fifth step involves retrieving the target values ​​for the motor speed and solenoid valve current at the next moment using a pre-defined two-dimensional mapping table of active support force and actuator target values. This mapping table, obtained through hydraulic system characteristic calibration, reflects the optimal combination of hydraulic pump motor speed and solenoid valve current under different active support force requirements.

[0152] In this embodiment, the target lateral acceleration is calculated in real time through a vehicle dynamics calculation model. The required active support force can be accurately calculated based on the actual dynamic parameters of the vehicle, adapting to dynamic changes under different load conditions, such as full load and no load. There is no need to calibrate the mapping table separately for each load condition, making it more accurate.

[0153] Furthermore, the target value of the instruction to be issued is obtained, and the target instruction is issued to the executor.

[0154] The target values ​​for motor speed and solenoid valve current output from the mapping table are used as the basic target values, and then corrected by combining the feedforward calculation results.

[0155] Target correction module 303: compares the actual height difference between the left and right sides of the vehicle with the preset target height difference; when the actual height difference exceeds the preset range of the target height difference, it corrects the target value of the motor speed and the target value of the solenoid valve current in real time.

[0156] The actual height difference between the left and right sides of the vehicle is obtained by a height sensor and compared with the preset target height difference.

[0157] The left-side height sensor measures the left-side vehicle height H. L The right-side height sensor measures the right-side vehicle height H. R Calculate the actual vehicle body height difference:

[0158] in, This represents the actual vehicle height difference. When... When the left side of the vehicle is higher than the right side, it indicates that the vehicle is tilting to the right; when This indicates that the right side of the vehicle is higher than the left, causing the vehicle to tilt to the left. The actual difference in vehicle height... Difference from the preset target vehicle height Compare the measurements and calculate the height deviation:

[0159] in, For height deviation; This parameter is typically set to a constant value close to 0mm, with 0mm being optimal, indicating that the vehicle body maintains a level posture. The height deviation is then compared to a preset deviation range of ±5mm: when | When | ≤ 5mm, the vehicle height difference is within the allowable range and no correction is needed; when | If the height difference is greater than 5mm, the vehicle height difference exceeds the allowable range, and a correction will be performed.

[0160] Furthermore, when the actual vehicle height difference exceeds the preset deviation range, the current target values ​​of motor speed and solenoid valve current are corrected based on the target values ​​of motor speed and solenoid valve current at the next moment.

[0161] The correction of target commands during actual vehicle movement includes functional safety verification to prevent the direction of the main force from reversing, which could lead to safety issues; and target value verification and correction. To overcome the limitations of multidimensional table calibration in mapping, closed-loop correction of the target values ​​is required.

[0162] First, the functional safety verification includes: calculating the height difference between the left and right sides (distinguishing between positive and negative) based on the height sensor signal of the current vehicle status, comparing the target active force direction based on the set target active force direction, and executing the action when the upward target active force and the lower posture side are on the same side, or the downward target active force and the higher posture side are on the same side, and stopping the action execution first when they are not on the same side for safety reasons.

[0163] Furthermore, the target value verification and correction are specifically as follows: Based on the vehicle height sensor signal, the height difference between the left and right vehicles is obtained, and the current height difference is compared with the target height difference. When the actual height difference is greater than the target height difference range, the system corrects the current motor target speed to improve accuracy. That is, the target is corrected in real time through height closed loop, resulting in a more precise control effect.

[0164] When the actual vehicle height difference exceeds the preset deviation range, according to the height deviation amount The current motor speed correction is performed by looking up a table: By establishing the calibrated correspondence between height deviation and motor speed, the correction amount for motor speed under the current height deviation is obtained. The correction amount is then added to the target value to obtain the current motor speed value.

[0165] For example, when the height deviation is 5mm, the speed is increased by 200rpm; when the height deviation is 10mm, the speed is increased by 400rpm.

[0166] Preferably, when the motor speed exceeds a certain threshold, a new solenoid valve current is obtained through a mapping table between the motor speed and the solenoid valve current. This embodiment considers that the solenoid valve may leak pressure; therefore, when a large main power is required, the solenoid valve needs to be adjusted to reduce throttling, decrease leakage, and increase main power.

[0167] In this module, the target values ​​for motor speed and solenoid valve current are initially set as the current motor speed and solenoid valve current. When the above height difference judgment is satisfied, the current motor speed and solenoid valve current are corrected. The corrected motor speed and solenoid valve current are then used as the current motor speed and solenoid valve current for execution. This process is repeated until the height difference is no greater than the target height difference range, and then the module returns to the feedforward judgment module 302.

[0168] Because there is a certain delay in the execution of the actuator, in order to improve the functional effect, this embodiment selects vehicle speed, steering wheel angle, and steering wheel angle acceleration as the judgment conditions for triggering the function, instead of selecting the IMU's lateral acceleration signal as the input signal for calculation. Moreover, the IMU's lateral acceleration signal has a large delay. When the signal is input, the vehicle's tilt has already occurred. When the actuator is executed, the effect is already significantly delayed, which is not conducive to the overall vehicle handling stability.

[0169] Loop optimization module 304: Based on the corrected target values ​​of motor speed and solenoid valve current, control the vehicle tilt within the target range in real time, and repeat the above process cyclically.

[0170] When the roll suppression function is activated, the feedforward judgment module 302 and the target correction module 303 are executed repeatedly at a preset frequency to implement closed-loop control until the data acquisition module 301 no longer feeds back the function activation signal.

[0171] The actual state of the vehicle may change suddenly (such as emergency avoidance). This embodiment can continuously correct the target through closed-loop feedback to ensure the driving stability of the vehicle.

[0172] Example 4 This embodiment provides a vehicle, including a memory and a processor, as well as computer instructions stored in the memory and running on the processor. When the computer instructions are executed by the processor, they complete the steps of the above-described control method for suppressing vehicle roll based on hydraulic active suspension.

[0173] Example 5 This embodiment provides a computer-readable storage medium for storing computer instructions, which, when executed by a processor, complete the steps of the above-described control method for suppressing vehicle roll based on hydraulic active suspension.

[0174] Example 6 This embodiment provides a computer program product including executable instructions, which are computer instructions; the executable instructions are stored in a computer-readable storage medium. When the vehicle's processor reads the executable instructions from the computer-readable storage medium and executes the executable instructions, the steps of the aforementioned control method for suppressing vehicle roll based on hydraulic active suspension are completed.

[0175] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0176] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0177] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment, whereby a series of operational steps are performed to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0178] The steps and methods involved in Embodiments 2 to 5 above correspond to those in Embodiment 1. For detailed implementation methods, please refer to the relevant description section of Embodiment 1. The descriptions of each embodiment in the above embodiments have different emphases. Parts not described in detail in a certain embodiment can be referred to the relevant descriptions of other embodiments.

[0179] Those skilled in the art will understand that the modules or steps of the present invention described above can be implemented using general-purpose computer devices. Optionally, they can be implemented using computer-executable program code, thereby allowing them to be stored in a storage device for execution by a computer device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. The present invention is not limited to any particular combination of hardware and software.

[0180] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A control method for suppressing vehicle roll based on hydraulic active suspension, characterized in that, include: The vehicle speed, steering wheel angle, and steering acceleration signals are acquired. When the vehicle speed signal reaches a preset vehicle speed threshold and the steering wheel angle signal reaches a preset angle threshold, roll suppression is performed. The system performs a feedforward judgment for roll suppression based on the steering wheel angle acceleration signal, combines the vehicle speed and steering wheel angle signals to obtain the target values ​​for motor speed and solenoid valve current, and then executes the target values. The actual height difference between the left and right sides of the vehicle is compared with the preset target height difference; when the actual height difference exceeds the preset range of the target height difference, the target values ​​of the motor speed and the solenoid valve current are corrected in real time. Based on the corrected target values ​​for motor speed and solenoid valve current, the vehicle tilt is controlled in real time within the target range, and the above process is repeated cyclically.

2. The control method for suppressing vehicle roll based on hydraulic active suspension as described in claim 1, characterized in that, Based on the steering wheel angle acceleration signal, a feedforward judgment is made to generate the changing trend of the roll suppression target: When the steering wheel angle acceleration signal is greater than zero, it indicates that the steering wheel is accelerating to the right, and it is predicted that the vehicle will tilt to the right. When the steering wheel angle acceleration signal is less than zero, it indicates that the steering wheel is accelerating to the left, and it is predicted that the vehicle will tilt to the left.

3. The control method for suppressing vehicle roll based on hydraulic active suspension as described in claim 1, characterized in that, Based on the steering wheel angle acceleration signal, a feedforward judgment for roll suppression is performed. Combined with vehicle speed and steering wheel angle signals, target values ​​for motor speed and solenoid valve current are obtained, including: The target value is obtained by looking up a multidimensional mapping table. or, The target value is obtained by using a vehicle dynamics calculation model with vehicle speed, steering wheel angle and steering wheel angle acceleration signals as input.

4. The control method for suppressing vehicle roll based on hydraulic active suspension as described in claim 3, characterized in that, The method of obtaining the target value by looking up a multidimensional mapping table is as follows: The angular acceleration signal, along with the vehicle speed and steering wheel angle, are used as input parameters. A pre-stored multidimensional mapping table is consulted to directly obtain the target values ​​of the motor speed and solenoid valve current for the next moment. The multidimensional mapping table is obtained through actual vehicle calibration.

5. The control method for suppressing vehicle roll based on hydraulic active suspension as described in claim 1, characterized in that, The target values ​​for motor speed and solenoid valve current are corrected in real time, including functional safety verification and target value verification and correction. The functional safety verification is performed by calculating the height difference between the left and right sides based on the height sensor signal of the current vehicle status, and comparing the calculated target active force direction. When the upward target active force and the lower side are on the same side, or the downward target active force and the higher side are on the same side, the action is executed. When they are not on the same side, the action is stopped.

6. The control method for suppressing vehicle roll based on hydraulic active suspension as described in claim 5, characterized in that, The target value verification and correction is as follows: when the actual vehicle height difference exceeds the preset deviation range, the correction amount of the motor speed under the current height deviation is obtained through the calibration correspondence between the height deviation and the motor speed, and the correction amount is added to the target value to obtain the current motor speed value.

7. A control system for vehicle roll suppression based on hydraulic active suspension, characterized in that, include: The data acquisition module is used to acquire vehicle speed, steering wheel angle and angular acceleration signals. When the vehicle speed signal reaches a preset vehicle speed threshold and the steering wheel angle signal reaches a preset angle threshold, roll suppression is performed. The feedforward judgment module is used to make feedforward judgments for roll suppression based on the steering wheel angle acceleration signal. It combines the vehicle speed and steering wheel angle signals to obtain the target values ​​of motor speed and solenoid valve current, and then executes the target values. The target correction module is used to compare the actual height difference between the left and right sides of the vehicle with the preset target height difference; when the actual height difference exceeds the preset range of the target height difference, the target values ​​of the motor speed and the solenoid valve current are corrected in real time. The loop optimization module is used to control the vehicle tilt within the target range in real time based on the corrected target values ​​of motor speed and solenoid valve current, and repeat the above process in a loop.

8. A vehicle, characterized in that, It includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, perform the control method for vehicle roll suppression based on any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, Used to store computer instructions, which, when executed by a processor, complete the control method for suppressing vehicle roll based on hydraulic active suspension as described in any one of claims 1-6.

10. A computer program product comprising executable instructions stored in a computer-readable storage medium; wherein, When the vehicle's processor reads executable instructions from a computer-readable storage medium and executes the executable instructions, it performs the control method for suppressing vehicle roll based on hydraulic active suspension as described in any one of claims 1-6.

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