Steering control method and device for vehicle active suspension

Abstract

The invention provides a vehicle active suspension steering control method and device.The steering control method comprises the steps that in the steering running process of a target vehicle, the expected yaw rate of the target vehicle is determined based on running speed data and a front wheel steering angle value; determining a yaw rate deviation value of the target vehicle based on a difference value between the actual yaw rate and the expected yaw rate and a yaw rate deviation value dead zone corresponding to the driving speed data so as to determine a steering state; determining a yaw control coefficient of the target vehicle based on the yaw rate deviation value and a control parameter corresponding to the steering state, and determining a preset numerical interval to which the yaw control coefficient belongs; and based on the yaw control coefficient and the transverse acceleration value, a control force output value of the active suspension in a preset numerical value interval is determined, and the active suspension is controlled to adjust the yaw motion state of the target vehicle. By means of the method, the control effect on the steering stability of the vehicle is improved, and then the safety and controllability of the vehicle during steering are improved.

Description

Technical Field

[0001] The present application relates to the technical field of vehicle vibration reduction, and in particular to a steering control method and device for a vehicle active suspension. Background Art

[0002] When a vehicle performs chassis control, it generally focuses on the roll and yaw motion during steering. The vehicle's active suspension system can suppress the torque generated by the roll angle by actively generating opposite vertical forces on the left and right. It can also control the yaw motion by adjusting the distribution of this torque between the front and rear axles. For example, when the vehicle understeers, the roll torque can be distributed more to the rear axle, and when the vehicle oversteers, the roll torque can be distributed more to the front axle, so that the vehicle is in a stable and safe state of neutral steering as much as possible.

[0003] At present, since the steering requirements of a vehicle may be different at different speeds, the traditional steering control system relies more on the steering system, differential braking system or distributed drive system to control the vehicle's steering, which has poor control effect on vehicle stability, thereby reducing the safety and controllability of the vehicle during steering. Summary of the Invention

[0004] In view of this, the purpose of the present application is to provide a steering control method and device for a vehicle active suspension, which obtains vehicle data during turning and determines the deviation between the current yaw rate of the vehicle and the expected yaw rate corresponding to neutral steering to determine the steering state of the vehicle, and replaces the fixed controller gain parameters and yaw rate deviation dead zone in traditional yaw control with parameters that change with vehicle speed. Further, by calculating the yaw control coefficient, the control force required by the active suspension is calculated in combination with the passive roll moment distribution coefficient and the roll moment, and outputs it to the active suspension to implement yaw control, thereby improving the control effect on the vehicle's steering stability, and thereby improving the safety and controllability of the vehicle during steering.

[0005] An embodiment of the present application provides a steering control method for a vehicle active suspension, the steering control method comprising:

[0006] During the turning process of the target vehicle, obtaining the target vehicle's driving speed data, front wheel steering angle value, actual yaw rate and lateral acceleration value, and determining the target vehicle's corresponding expected yaw rate based on the driving speed data and the front wheel steering angle value;

[0007] determining a yaw rate deviation value of the target vehicle based on a difference between an absolute value corresponding to the actual yaw rate and an absolute value corresponding to the desired yaw rate and a yaw rate deviation value dead band corresponding to the driving speed data to determine a steering state of the target vehicle;

[0008] determining a yaw control coefficient of the target vehicle in each of the steering states based on the yaw rate deviation value and a control parameter corresponding to the steering state, and determining a preset value range to which the yaw control coefficient belongs;

[0009] For each of the preset numerical intervals, based on the yaw control coefficient and the lateral acceleration value, a control force output value of the active suspension of the target vehicle within the preset numerical interval is determined, and the active suspension is controlled to adjust the yaw motion state of the target vehicle according to the control force output value.

[0010] Furthermore, determining the expected yaw rate corresponding to the target vehicle based on the driving speed data and the front wheel steering angle value includes:

[0011] Determining a longitudinal speed value of the target vehicle from the driving speed data, and respectively determining a wheelbase value and an understeer parameter of the target vehicle from preset parameters of the target vehicle;

[0012] An expected yaw rate corresponding to the target vehicle is calculated and determined based on the longitudinal speed value, the front wheel steering angle value, the wheelbase value, and the understeer parameter.

[0013] Furthermore, determining the yaw rate deviation value of the target vehicle based on the difference between the absolute value corresponding to the actual yaw rate and the absolute value corresponding to the expected yaw rate and a yaw rate deviation value dead band corresponding to the driving speed data to determine the steering state of the target vehicle includes:

[0014] subtracting an absolute value corresponding to the actual yaw rate from an absolute value corresponding to the expected yaw rate to determine a difference between the actual yaw rate and the expected yaw rate;

[0015] comparing the difference with a yaw rate deviation dead zone corresponding to the driving speed data to obtain a comparison result;

[0016] For each comparison result, determining a yaw rate deviation value of the target vehicle under the comparison result based on the difference and a boundary parameter corresponding to the yaw rate deviation dead zone;

[0017] The steering state of the target vehicle is determined based on the positive and negative performances corresponding to the yaw rate deviation values.

[0018] Furthermore, for each comparison result, determining the yaw rate deviation value of the target vehicle under the comparison result based on the difference and a boundary parameter corresponding to the yaw rate deviation dead zone includes:

[0019] When the comparison result shows that the difference is greater than a first boundary parameter corresponding to the yaw rate deviation dead zone, determining the difference between the difference and the first boundary parameter as the yaw rate deviation value of the target vehicle under the comparison result;

[0020] When the comparison result shows that the difference is less than or equal to a first boundary parameter corresponding to the yaw rate deviation value dead zone and the difference is greater than or equal to a second boundary parameter corresponding to the yaw rate deviation value dead zone, determining a first preset value as the yaw rate deviation value of the target vehicle under the comparison result;

[0021] When the comparison result is that the difference is smaller than the second boundary parameter corresponding to the yaw rate deviation dead zone, the difference between the difference and the second boundary parameter is determined as the yaw rate deviation value of the target vehicle under the comparison result.

[0022] Furthermore, determining the steering state of the target vehicle based on the positive and negative performance corresponding to the yaw rate deviation value includes:

[0023] When the yaw rate deviation value is equal to a first preset value, determining that the steering state of the target vehicle is a neutral steering state;

[0024] When the yaw rate deviation value is positive, determining that the steering state of the target vehicle is an oversteering state;

[0025] When the yaw rate deviation value is negative, it is determined that the steering state of the target vehicle is an understeering state.

[0026] Furthermore, determining a yaw control coefficient of the target vehicle in each of the steering states based on the yaw rate deviation value and the control parameter corresponding to the steering state, and determining a preset value range to which the yaw control coefficient belongs, includes:

[0027] When the steering state is an understeering state, determining a yaw control coefficient of the target vehicle in the understeering state based on the yaw rate deviation value and a first control parameter corresponding to the understeering state;

[0028] When the steering state is a neutral steering state or an oversteering state, determining a yaw control coefficient of the target vehicle in the neutral steering state or the oversteering state based on the yaw rate deviation value and a second control parameter corresponding to the oversteering state;

[0029] The yaw control coefficient is compared with a first preset value and a second preset value respectively, and based on the comparison results, a preset value range to which the yaw control coefficient belongs is determined.

[0030] Furthermore, for each of the preset numerical intervals, determining a control force output value of the active suspension of the target vehicle within the preset numerical interval based on the yaw control coefficient and the lateral acceleration value includes:

[0031] determining an active suspension roll moment value and a passive roll moment distribution coefficient of the target vehicle based on the lateral acceleration value and preset parameters of the target vehicle;

[0032] When the preset numerical interval to which the yaw control coefficient belongs is a first preset numerical interval, determining control force output values of a left front active suspension, a right front active suspension, a left rear active suspension, and a right rear active suspension of the target vehicle, respectively, within the first preset numerical interval based on the wheelbase value of the target vehicle, the yaw control coefficient, the active suspension roll moment value, and the passive roll moment distribution coefficient;

[0033] When the preset numerical interval to which the yaw control coefficient belongs is the second preset numerical interval or the third preset numerical interval, based on the wheelbase value of the target vehicle, the active suspension roll moment value and the passive roll moment distribution coefficient, the control force output values of the left front active suspension, the right front active suspension, the left rear active suspension and the right rear active suspension of the target vehicle are determined in the second preset numerical interval or the third preset numerical interval respectively.

[0034] Furthermore, the determining of the active suspension roll moment value and the passive roll moment distribution coefficient of the target vehicle based on the lateral acceleration value and the preset parameters of the target vehicle includes:

[0035] Determining the target vehicle's vehicle mass, sprung mass, front axle roll center height, rear axle roll center height, sprung mass center height, target roll angle, front axle suspension roll stiffness, rear axle suspension roll stiffness, front axle mass ratio, and rear axle mass ratio from the preset parameters of the target vehicle;

[0036] Calculating and determining a center-of-mass roll moment value of the target vehicle based on the lateral acceleration value, the gravitational acceleration at the location of the target vehicle, the sprung mass, the vehicle front axle roll center height value, the vehicle rear axle roll center height value, the sprung mass center-of-mass height value, and the target roll angle value;

[0037] Calculating and determining an active suspension roll moment value of the target vehicle based on the center of mass roll moment value, the target roll angle value, the front axle suspension roll stiffness, and the rear axle suspension roll stiffness;

[0038] The passive roll moment distribution coefficient of the target vehicle is calculated and determined based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, the front axle mass ratio and the rear axle mass ratio.

[0039] Furthermore, the calculating and determining the passive roll moment distribution coefficient of the target vehicle based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, the front axle mass ratio, and the rear axle mass ratio includes:

[0040] Calculating and determining a front axle distributed torque value corresponding to the active suspension of the target vehicle when not actively generating an output force based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, and the front axle mass ratio;

[0041] Calculating and determining a rear axle distributed torque value corresponding to the active suspension of the target vehicle when not actively generating an output force based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, and the rear axle mass ratio;

[0042] The front axle distributed torque value and the rear axle distributed torque value are added to obtain an addition result, and the ratio between the front axle distributed torque value and the addition result is determined as the passive roll torque distribution coefficient of the target vehicle.

[0043] The present application also provides a steering control device for an active suspension of a vehicle, the steering control device comprising:

[0044] an expected calculation module, configured to obtain a driving speed data, a front wheel steering angle value, an actual yaw rate, and a lateral acceleration value of the target vehicle during the target vehicle's turning process, and determine an expected yaw rate corresponding to the target vehicle based on the driving speed data and the front wheel steering angle value;

[0045] a deviation calculation module, configured to determine a yaw rate deviation value of the target vehicle based on a difference between an absolute value corresponding to the actual yaw rate and an absolute value corresponding to the desired yaw rate and a yaw rate deviation value dead band corresponding to the driving speed data, so as to determine a steering state of the target vehicle;

[0046] a yaw control module, configured to determine a yaw control coefficient of the target vehicle in each of the steering states based on the yaw rate deviation value and a control parameter corresponding to the steering state, and to determine a preset value range to which the yaw control coefficient belongs;

[0047] an output control module for determining, for each of the preset numerical intervals, a control force output value of the active suspension of the target vehicle within the preset numerical interval based on the yaw control coefficient and the lateral acceleration value, and controlling the active suspension to adjust the yaw motion state of the target vehicle according to the control force output value.

[0048] Furthermore, when the expectation calculation module is used to determine the expected yaw rate corresponding to the target vehicle based on the driving speed data and the front wheel steering angle value, the expectation calculation module is used to:

[0049] Determining a longitudinal speed value of the target vehicle from the driving speed data, and respectively determining a wheelbase value and an understeer parameter of the target vehicle from preset parameters of the target vehicle;

[0050] An expected yaw rate corresponding to the target vehicle is calculated and determined based on the longitudinal speed value, the front wheel steering angle value, the wheelbase value, and the understeer parameter.

[0051] Furthermore, when the deviation calculation module is configured to determine the yaw rate deviation value of the target vehicle based on the difference between the absolute value corresponding to the actual yaw rate and the absolute value corresponding to the expected yaw rate and the yaw rate deviation value dead band corresponding to the driving speed data, so as to determine the turning state of the target vehicle, the deviation calculation module is configured to:

[0052] subtracting an absolute value corresponding to the actual yaw rate from an absolute value corresponding to the expected yaw rate to determine a difference between the actual yaw rate and the expected yaw rate;

[0053] comparing the difference with a yaw rate deviation dead zone corresponding to the driving speed data to obtain a comparison result;

[0054] For each comparison result, determining a yaw rate deviation value of the target vehicle under the comparison result based on the difference and a boundary parameter corresponding to the yaw rate deviation dead zone;

[0055] The steering state of the target vehicle is determined based on the positive and negative performances corresponding to the yaw rate deviation values.

[0056] Furthermore, when the deviation calculation module is used to determine, for each comparison result, the yaw rate deviation value of the target vehicle based on the difference and the boundary parameter corresponding to the yaw rate deviation dead zone, the deviation calculation module is used to:

[0057] When the comparison result shows that the difference is greater than a first boundary parameter corresponding to the yaw rate deviation dead zone, determining the difference between the difference and the first boundary parameter as the yaw rate deviation value of the target vehicle under the comparison result;

[0058] When the comparison result shows that the difference is less than or equal to a first boundary parameter corresponding to the yaw rate deviation value dead zone and the difference is greater than or equal to a second boundary parameter corresponding to the yaw rate deviation value dead zone, determining a first preset value as the yaw rate deviation value of the target vehicle under the comparison result;

[0059] When the comparison result is that the difference is smaller than the second boundary parameter corresponding to the yaw rate deviation dead zone, the difference between the difference and the second boundary parameter is determined as the yaw rate deviation value of the target vehicle under the comparison result.

[0060] Furthermore, when the deviation calculation module is used to determine the steering state of the target vehicle based on the positive and negative performance corresponding to the yaw rate deviation value, the deviation calculation module is used to:

[0061] When the yaw rate deviation value is equal to a first preset value, determining that the steering state of the target vehicle is a neutral steering state;

[0062] When the yaw rate deviation value is positive, determining that the steering state of the target vehicle is an oversteering state;

[0063] When the yaw rate deviation value is negative, it is determined that the steering state of the target vehicle is an understeering state.

[0064] Furthermore, when the yaw control module is configured to determine a yaw control coefficient of the target vehicle in each of the steering states based on the yaw rate deviation value and the control parameter corresponding to the steering state, and to determine a preset value range to which the yaw control coefficient belongs, the yaw control module is configured to:

[0065] When the steering state is an understeering state, determining a yaw control coefficient of the target vehicle in the understeering state based on the yaw rate deviation value and a first control parameter corresponding to the understeering state;

[0066] When the steering state is a neutral steering state or an oversteering state, determining a yaw control coefficient of the target vehicle in the neutral steering state or the oversteering state based on the yaw rate deviation value and a second control parameter corresponding to the oversteering state;

[0067] The yaw control coefficient is compared with a first preset value and a second preset value respectively, and based on the comparison results, a preset value range to which the yaw control coefficient belongs is determined.

[0068] Furthermore, when the output control module is used to determine, for each preset numerical interval, based on the yaw control coefficient and the lateral acceleration value, the control force output value of the active suspension of the target vehicle within the preset numerical interval, the output control module is used to:

[0069] determining an active suspension roll moment value and a passive roll moment distribution coefficient of the target vehicle based on the lateral acceleration value and preset parameters of the target vehicle;

[0070] When the preset numerical interval to which the yaw control coefficient belongs is a first preset numerical interval, determining control force output values of a left front active suspension, a right front active suspension, a left rear active suspension, and a right rear active suspension of the target vehicle, respectively, within the first preset numerical interval based on the wheelbase value of the target vehicle, the yaw control coefficient, the active suspension roll moment value, and the passive roll moment distribution coefficient;

[0071] When the preset numerical interval to which the yaw control coefficient belongs is the second preset numerical interval or the third preset numerical interval, based on the wheelbase value of the target vehicle, the active suspension roll moment value and the passive roll moment distribution coefficient, the control force output values of the left front active suspension, the right front active suspension, the left rear active suspension and the right rear active suspension of the target vehicle are determined in the second preset numerical interval or the third preset numerical interval respectively.

[0072] Furthermore, when the output control module is used to determine the active suspension roll moment value and the passive roll moment distribution coefficient of the target vehicle based on the lateral acceleration value and the preset parameters of the target vehicle, the output control module is used to:

[0073] Determining the target vehicle's vehicle mass, sprung mass, front axle roll center height, rear axle roll center height, sprung mass center height, target roll angle, front axle suspension roll stiffness, rear axle suspension roll stiffness, front axle mass ratio, and rear axle mass ratio from the preset parameters of the target vehicle;

[0074] Calculating and determining a center-of-mass roll moment value of the target vehicle based on the lateral acceleration value, the gravitational acceleration at the location of the target vehicle, the sprung mass, the vehicle front axle roll center height value, the vehicle rear axle roll center height value, the sprung mass center-of-mass height value, and the target roll angle value;

[0075] Calculating and determining an active suspension roll moment value of the target vehicle based on the center of mass roll moment value, the target roll angle value, the front axle suspension roll stiffness, and the rear axle suspension roll stiffness;

[0076] The passive roll moment distribution coefficient of the target vehicle is calculated and determined based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, the front axle mass ratio and the rear axle mass ratio.

[0077] Furthermore, when the output control module is used to calculate and determine the passive roll moment distribution coefficient of the target vehicle based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, the front axle mass ratio, and the rear axle mass ratio, the output control module is used to:

[0078] Calculating and determining a front axle distributed torque value corresponding to the active suspension of the target vehicle when not actively generating an output force based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, and the front axle mass ratio;

[0079] Calculating and determining a rear axle distributed torque value corresponding to the active suspension of the target vehicle when not actively generating an output force based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, and the rear axle mass ratio;

[0080] The front axle distributed torque value and the rear axle distributed torque value are added to obtain an addition result, and the ratio between the front axle distributed torque value and the addition result is determined as the passive roll torque distribution coefficient of the target vehicle.

[0081] An embodiment of the present application also provides an electronic device, comprising: a processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor and the memory communicate through the bus, and when the machine-readable instructions are executed by the processor, the steps of the steering control method of the vehicle active suspension as described above are performed.

[0082] An embodiment of the present application further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the steering control method for the vehicle active suspension as described above are executed.

[0083] Embodiments of the present application provide a steering control method and device for a vehicle active suspension. The steering control method includes: obtaining driving speed data, a front wheel steering angle value, an actual yaw rate, and a lateral acceleration value of a target vehicle during steering, and determining a desired yaw rate corresponding to the target vehicle based on the driving speed data and the front wheel steering angle value; determining a yaw rate deviation value of the target vehicle based on a difference between an absolute value corresponding to the actual yaw rate and an absolute value corresponding to the desired yaw rate and a dead band of a yaw rate deviation value corresponding to the driving speed data, so as to determine a steering state of the target vehicle; determining a yaw control coefficient of the target vehicle in each steering state based on the yaw rate deviation value and a control parameter corresponding to the steering state, and determining a preset value range to which the yaw control coefficient belongs; and determining, for each preset value range, a control force output value of the active suspension of the target vehicle in the preset value range based on the yaw control coefficient and the lateral acceleration value, and controlling the active suspension to adjust the yaw motion state of the target vehicle according to the control force output value.

[0084] Compared with the steering method in the prior art that relies on a steering system, a differential braking system or a distributed drive system to control the vehicle, the vehicle data of the vehicle during turning is obtained to determine the deviation between the current yaw rate of the vehicle and the expected yaw rate corresponding to neutral steering, so as to determine the steering state of the vehicle, and replace the fixed controller gain parameters and yaw rate deviation dead zone in traditional yaw control with parameters that change with vehicle speed. Furthermore, by calculating the yaw control coefficient, the control force required by the active suspension is calculated in combination with the passive roll moment distribution coefficient and the roll moment, and the control force is output to the active suspension to implement yaw control, thereby improving the control effect of the vehicle's steering stability, thereby improving the safety and handling of the vehicle during steering.

[0085] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0086] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0087] Figure 1 A flowchart of a steering control method for a vehicle active suspension provided in an embodiment of the present application;

[0088] Figure 2 A schematic structural diagram of a vehicle active suspension system provided in an embodiment of the present application;

[0089] Figure 3 A schematic diagram of a driving trajectory of a vehicle steering control provided in an embodiment of the present application;

[0090] Figure 4 A schematic structural diagram of a steering control device for a vehicle active suspension provided in an embodiment of the present application;

[0091] Figure 5 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0092] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application for which protection is claimed, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, each other embodiment obtained by those skilled in the art without making creative work falls within the scope of protection of the present application.

[0093] Research has found that with the development of automobile technology, active suspension that can adjust vertical support force and damping has become a new trend in chassis intelligence development. Compared with traditional passive suspension, active suspension systems can use hydraulic mechanisms, electromechanical mechanisms or electro-hydraulic hybrid mechanisms that can adjust or output active force, combined with electronic control units, sensors and on-board network information to control suspension motion, thereby improving vehicle chassis performance and enhancing vehicle ride comfort and driving controllability.

[0094] At present, since the steering requirements of a vehicle may be different at different speeds, for example, at low speeds, appropriate oversteering can reduce the turning radius and make the vehicle more flexible, while at high speeds, suppressing oversteering can improve safety.

[0095] The goal of traditional steering control systems is to rely more on steering systems, differential braking systems or distributed drive systems to control the steering of the vehicle, which has poor control effect on vehicle stability, thereby reducing the safety and controllability of the vehicle during steering.

[0096] Based on this, an embodiment of the present application provides a steering control method for a vehicle active suspension. By acquiring vehicle data of the vehicle during turning driving, the deviation between the current yaw rate of the vehicle and the expected yaw rate corresponding to neutral steering is determined to determine the steering state of the vehicle, and the fixed controller gain parameters and yaw rate deviation dead zone in traditional yaw control are replaced with parameters that change with vehicle speed. Further, by calculating the yaw control coefficient, the control force required by the active suspension is calculated in combination with the passive roll moment distribution coefficient and the roll moment, and the control force is output to the active suspension to implement yaw control, thereby improving the control effect on the vehicle's steering stability, and thereby improving the safety and controllability of the vehicle during steering.

[0097] See also Figure 1 , Figure 1 This is a flow chart of a steering control method for a vehicle active suspension provided in an embodiment of the present application. Figure 1 As shown in , the steering control method of the vehicle active suspension provided by the embodiment of the present application includes:

[0098] S100. During the turning process of the target vehicle, obtain the driving speed data, front wheel steering angle value, actual yaw rate and lateral acceleration value of the target vehicle, and determine the expected yaw rate corresponding to the target vehicle based on the driving speed data and the front wheel steering angle value.

[0099] In this step, the target vehicle's driving speed data, front wheel steering angle value, actual yaw rate, and lateral acceleration value are obtained using the CAN network set in the target vehicle; then, the preset parameters of the target vehicle are determined; and based on the driving speed data, front wheel steering angle value, and specified parameters in the preset parameters, the expected yaw rate corresponding to the target vehicle is determined.

[0100] Here, the desired yaw rate refers to the ideal vehicle rotation speed around the vertical axis calculated based on the driver's operating input and the vehicle's current driving state during vehicle dynamic control. The desired yaw rate is an important parameter in the vehicle stability control system, used to evaluate and adjust the vehicle's actual behavior to match the driver's intention.

[0101] The driving speed data may include but is not limited to a longitudinal speed value, a lateral speed value, and a comprehensive speed value; and the front wheel steering angle value may be obtained by proportional conversion based on the steering angle of the driver's steering wheel.

[0102] In one embodiment of the present application, in a specific implementation, the step of determining the expected yaw rate corresponding to the target vehicle based on the driving speed data and the front wheel steering angle value in step S100 may include:

[0103] S110 , determining a longitudinal speed value of the target vehicle from the driving speed data, and respectively determining a wheelbase value and an understeer parameter of the target vehicle from preset parameters of the target vehicle.

[0104] In an embodiment of the present application, the wheelbase value of the target vehicle represents the distance between the centers of the left and right tires of the target vehicle; the understeer parameter can be calibrated in advance by analyzing the vehicle's geometric layout and tire characteristics when the target vehicle is in a neutral steering state, and is used to describe the parameters of the vehicle's understeer characteristics in a stable state.

[0105] S120: Calculate and determine an expected yaw rate corresponding to the target vehicle based on the longitudinal speed value, the front wheel steering angle value, the wheelbase value, and the understeer parameter.

[0106] In the embodiment of the present application, the formula for calculating the expected yaw rate corresponding to the target vehicle is as follows.

[0107]

[0108] Among them, γ tar is the expected yaw rate corresponding to the target vehicle; δ is the front wheel steering angle; v x is the longitudinal speed value; L is the wheelbase value; K us is the understeering parameter.

[0109] S200. Determine a yaw rate deviation value of the target vehicle based on a difference between an absolute value corresponding to the actual yaw rate and an absolute value corresponding to the desired yaw rate and a yaw rate deviation value dead zone corresponding to the driving speed data to determine a steering state of the target vehicle.

[0110] In one embodiment of the present application, during specific implementation, step S200 may include:

[0111] S210 : Subtract an absolute value corresponding to the actual yaw rate from an absolute value corresponding to the expected yaw rate to determine a difference between the actual yaw rate and the expected yaw rate.

[0112] In the embodiment of the present application, the positive and negative expressions of the actual yaw rate and the expected yaw rate are used to indicate whether the target vehicle is turning left or turning right. Specifically, when the target vehicle is turning left, the actual yaw rate and the expected yaw rate are both positive; when the target vehicle is turning right, the actual yaw rate and the expected yaw rate are both negative.

[0113] In this step, the absolute value corresponding to the desired yaw rate is subtracted from the absolute value corresponding to the actual yaw rate to obtain the difference between the actual yaw rate and the desired yaw rate.

[0114] S220 : Compare the difference with the yaw rate deviation dead zone corresponding to the driving speed data to obtain a comparison result.

[0115] In the embodiment of the present application, the yaw rate deviation deadband generally refers to a range of yaw rate deviation allowed by the vehicle. Within this range, the vehicle dynamic control system will not intervene because the deviation is considered to be within an acceptable range and may be a minor change caused by normal operation of the driver.

[0116] In this step, based on the driving speed data, a preset one-dimensional comparison table of speed and yaw rate deviation value dead zone is used to determine the boundary parameters of the yaw rate deviation value dead zone, that is, the first boundary parameter and the second boundary parameter of the yaw rate deviation value dead zone. Then, the difference is compared with the boundary parameters of the yaw rate deviation value dead zone to determine the comparison result.

[0117] Here, the comparison result may include that the difference is less than or equal to the first boundary parameter corresponding to the yaw rate deviation value dead zone and the difference is greater than or equal to the second boundary parameter corresponding to the yaw rate deviation value dead zone; the difference is greater than the first boundary parameter corresponding to the yaw rate deviation value dead zone; the difference is less than the second boundary parameter corresponding to the yaw rate deviation value dead zone.

[0118] The first boundary parameter of the yaw rate deviation dead zone represents the upper limit of the yaw rate deviation dead zone; and the second boundary parameter of the yaw rate deviation dead zone represents the lower limit of the yaw rate deviation dead zone.

[0119] In this way, when calculating the yaw rate deviation value, the dynamic dead zone link is applied. The range of the yaw rate deviation value dead zone that changes with vehicle speed can be used to change the allowable degree of understeer or oversteer at different vehicle speeds, thereby improving the safety and controllability of the vehicle during steering.

[0120] S230 : For each comparison result, determine the yaw rate deviation value of the target vehicle under the comparison result based on the difference and a boundary parameter corresponding to the yaw rate deviation dead zone.

[0121] In one embodiment of the present application, during specific implementation, step S230 may include:

[0122] S231. When the comparison result shows that the difference is greater than a first boundary parameter corresponding to the yaw rate deviation dead zone, determine the difference between the difference and the first boundary parameter as the yaw rate deviation value of the target vehicle under this comparison result.

[0123] In the embodiment of the present application, when the difference is greater than the first boundary parameter corresponding to the yaw rate deviation dead zone, the expression for calculating the yaw rate deviation is as follows.

[0124] γ e =|γ|-|γ tar |-γ db1 ,|γ|-|γ tar |>γ db1 .

[0125] Among them, γ e represents the yaw rate deviation value; |γ| represents the absolute value corresponding to the actual yaw rate; |γ tar | represents the absolute value corresponding to the desired yaw rate; γ db1 Indicates the first boundary parameter corresponding to the yaw rate deviation dead zone.

[0126] S232. When the comparison result is that the difference is less than or equal to the first boundary parameter corresponding to the yaw rate deviation value dead zone and the difference is greater than or equal to the second boundary parameter corresponding to the yaw rate deviation value dead zone, determine the first preset value as the yaw rate deviation value of the target vehicle under this comparison result.

[0127] In an embodiment of the present application, the first preset value is generally set to 0; when the difference is less than or equal to the first boundary parameter corresponding to the yaw rate deviation value dead zone and the difference is greater than or equal to the second boundary parameter corresponding to the yaw rate deviation value dead zone, the expression for calculating the yaw rate deviation value is as follows.

[0128] γ e =0,γ db0 ≤|γ|-|γ tar |≤γ db1 .

[0129] Among them, γ e represents the yaw rate deviation value; |γ| represents the absolute value corresponding to the actual yaw rate; |γ tar | represents the absolute value corresponding to the desired yaw rate; γ db1 represents the first boundary parameter corresponding to the dead zone of yaw rate deviation value; γ db0 Indicates the second boundary parameter corresponding to the yaw rate deviation dead zone.

[0130] S233: When the comparison result shows that the difference is smaller than a second boundary parameter corresponding to the yaw rate deviation dead zone, determine the difference between the difference and the second boundary parameter as the yaw rate deviation value of the target vehicle under this comparison result.

[0131] In the embodiment of the present application, when the difference is less than the second boundary parameter corresponding to the yaw rate deviation dead zone, the expression for calculating the yaw rate deviation is as follows.

[0132] γ e =γ|-|γ tar |-γ db0 ,|γ|-|γ tar |<γ db0 .

[0133] Among them, γ e represents the yaw rate deviation value; |γ| represents the absolute value corresponding to the actual yaw rate; |γ tar | represents the absolute value corresponding to the desired yaw rate; γ db0 Indicates the second boundary parameter corresponding to the yaw rate deviation dead zone.

[0134] S234 : Determine the steering state of the target vehicle based on the positive and negative performances corresponding to the yaw rate deviation value.

[0135] In one embodiment of the present application, during specific implementation, step S234 may include:

[0136] S2341. When the yaw rate deviation value is equal to a first preset value, determine that the steering state of the target vehicle is a neutral steering state.

[0137] In this step, when the yaw rate deviation value is equal to 0, the steering state of the target vehicle is determined to be a neutral steering state. That is, the vehicle turns accurately according to the driver's intention and the input steering wheel angle, and no additional direction correction is required. At this time, the front and rear wheel slip angles of the vehicle enable the vehicle to maintain an ideal turning trajectory, providing optimal handling stability and driving experience.

[0138] S2342: When the yaw rate deviation value is positive, determine that the steering state of the target vehicle is an oversteering state.

[0139] In this step, when the yaw rate deviation value is greater than 0, the steering state of the target vehicle is determined to be an oversteering state, that is, the vehicle will turn along a smaller arc than expected, which may cause the rear end of the vehicle to slide outward, increasing the risk of loss of control.

[0140] S2343: When the yaw rate deviation value is negative, determine that the steering state of the target vehicle is an understeering state.

[0141] In this step, when the yaw rate deviation value is less than 0, the steering state of the target vehicle is determined to be an understeer state, that is, the vehicle will turn along a larger arc than expected, the vehicle's turning radius is greater than the ideal value, and a larger steering wheel angle is usually required to achieve the desired turning path.

[0142] S300 , determining a yaw control coefficient of the target vehicle in each of the steering states based on the yaw rate deviation value and the control parameter corresponding to the steering state, and determining a preset value range to which the yaw control coefficient belongs.

[0143] In the embodiment of the present application, the control parameter corresponding to the steering state represents a PID control parameter. The control parameter corresponding to the steering state can change with the vehicle speed. In engineering, the value change is generally achieved through a one-dimensional lookup table with the vehicle speed as the reference point, and the value of this table is modified through calibration during the actual vehicle test.

[0144] The control parameters corresponding to the steering state may include a first control parameter corresponding to an understeering state and a second control parameter corresponding to an oversteering state.

[0145] In this way, applying different control parameters for different steering states and different vehicle speeds can effectively solve the problem that fixed yaw control parameters cannot change the yaw control target with vehicle speed, so as to better meet the yaw stability control requirements at different vehicle speeds and further improve the vehicle's controllability during steering.

[0146] In one embodiment of the present application, during specific implementation, step S300 may include:

[0147] S310: When the steering state is an understeering state, determine a yaw control coefficient of the target vehicle in the understeering state based on the yaw rate deviation value and a first control parameter corresponding to the understeering state.

[0148] In the embodiment of the present application, the expression for calculating the yaw control coefficient of the target vehicle in the understeering state is as follows.

[0149]

[0150] Among them, λ actv Indicates the yaw control coefficient; K pu , K iu and K du represents the first control parameter corresponding to the understeering state; γ e Indicates the yaw rate deviation value.

[0151] S320. When the steering state is a neutral steering state or an oversteering state, determine the yaw control coefficient of the target vehicle in the neutral steering state or the oversteering state based on the yaw rate deviation value and a second control parameter corresponding to the oversteering state.

[0152] In an embodiment of the present application, an expression for calculating the yaw control coefficient of the target vehicle in a neutral steering state or an oversteering state is as follows.

[0153]

[0154] Among them, λ actv Indicates the yaw control coefficient; K po , K io and K do represents the second control parameter corresponding to the oversteering state; γ e Indicates the yaw rate deviation value.

[0155] S330: Compare the yaw control coefficient with a first preset value and a second preset value respectively, and determine the preset value range to which the yaw control coefficient belongs based on the comparison results.

[0156] Here, the preset numerical interval may include a first preset numerical interval, a second preset numerical interval, and a third preset numerical interval.

[0157] In the embodiment of the present application, the first preset value is generally set to 0, and the second preset value is generally set to 1, that is, the first preset numerical interval is (0,1); the second preset numerical interval is (-∞,0]; and the third preset numerical interval is [1,+∞).

[0158] In this step, the yaw control coefficient is compared with 1 and 0 respectively to determine whether the comparison result of the yaw control coefficient is greater than or equal to 1, less than or equal to 0, or between 0 and 1, that is, to determine the preset numerical range to which the yaw control coefficient belongs.

[0159] S400. For each of the preset numerical intervals, based on the yaw control coefficient and the lateral acceleration value, determine a control force output value of the active suspension of the target vehicle within the preset numerical interval, and control the active suspension to adjust the yaw motion state of the target vehicle according to the control force output value.

[0160] In this step, after determining the control force output value of the active suspension of the target vehicle in each preset numerical range, the control force output value can be added to the output values of other control strategies to obtain the target output value, and the target output value is sent as an instruction to the active suspension actuator to control the vehicle's yaw motion state and improve steering stability.

[0161] For example, see Figure 2 , Figure 2 This is a schematic diagram of the structure of a vehicle active suspension system provided in an embodiment of the present application. Figure 2As shown in , the steering control device of the vehicle active suspension provided in the embodiment of the present application receives vehicle network information, executes the steering control method of the vehicle active suspension provided in the embodiment of the present application, and obtains a target output value; then, the target output value is sent to the active suspension actuator as an instruction, and the actuator generates an active control force that is not affected by the passive spring force and the passive damping force according to the control instruction, thereby changing the vehicle chassis motion dynamics.

[0162] In one embodiment of the present application, in specific implementation, the step of determining, for each of the preset numerical intervals, based on the yaw control coefficient and the lateral acceleration value, the control force output value of the active suspension of the target vehicle within the preset numerical interval in step S400 may include:

[0163] S410: Based on the lateral acceleration value and preset parameters of the target vehicle, determine the active suspension roll moment value and the passive roll moment distribution coefficient of the target vehicle respectively.

[0164] In one embodiment of the present application, during specific implementation, step S410 may include:

[0165] S411. Determine the vehicle mass, sprung mass, front axle roll center height value, rear axle roll center height value, sprung mass center height value, target roll angle value, front axle suspension roll stiffness, rear axle suspension roll stiffness, front axle mass ratio, and rear axle mass ratio of the target vehicle from the preset parameters of the target vehicle.

[0166] In the embodiment of the present application, the vehicle front axle roll center height value and the vehicle rear axle roll center height value represent the heights of the roll centers of the front and rear axles of the vehicle relative to the ground; the sprung mass center of mass height value represents the height of the sprung mass center of mass of the vehicle relative to the ground; the front axle mass ratio and the rear axle mass ratio are the distribution ratios of the vehicle weight on the front and rear axles, respectively, and the sum of the front axle mass ratio and the rear axle mass ratio must be 1.

[0167] Among them, the target roll angle value is the target roll angle in the roll angle control. Generally, roll angle control and yaw control are applied simultaneously in engineering to adjust the lateral movement of the vehicle. Compared with using the estimated actual vehicle body roll angle, using the target roll angle is more conducive to maintaining the stability of the control output and avoiding the disturbance caused by the actuator being amplified by the estimator and destroying the stability of the roll.

[0168] S412. Calculate and determine a center-of-mass roll moment value of the target vehicle based on the lateral acceleration value, the gravitational acceleration at the location of the target vehicle, the sprung mass, the vehicle front axle roll center height value, the vehicle rear axle roll center height value, the sprung mass center-of-mass height value, and the target roll angle value.

[0169] In the embodiment of the present application, the center-of-mass roll moment value represents the roll moment acting at the center of mass of the vehicle body when the vehicle turns, and the formula for calculating the center-of-mass roll moment value of the target vehicle is as follows.

[0170]

[0171] Among them, M cog Indicates the center of mass roll moment value; m s Indicates sprung mass; h f and h r Respectively represent the vehicle's front axle roll center height value and the vehicle's rear axle roll center height value; h cog Indicates the height of the center of mass of the sprung mass; a y Indicates the lateral acceleration value; g indicates the acceleration of gravity at the location of the target vehicle; Indicates the target roll angle value.

[0172] S413 . Calculate and determine an active suspension roll moment value of the target vehicle based on the center-of-mass roll moment value, the target roll angle value, the front axle suspension roll stiffness, and the rear axle suspension roll stiffness.

[0173] In this step, when calculating the active suspension roll moment value of the target vehicle, an open-loop roll angle control strategy is applied. The application of this roll angle control strategy is not limited to a specific method, that is, any change in the vehicle's roll angle control strategy does not affect the control effect of calculating the active suspension yaw control force based on the active suspension roll moment value given in the present invention.

[0174] In an embodiment of the present application, the formula for calculating the active suspension roll moment value of the target vehicle is as follows.

[0175]

[0176] in, Indicates the active suspension roll moment value; M cog Indicates the center of mass rolling moment value; Indicates the target roll angle value; and They represent the front axle suspension roll stiffness and the rear axle suspension roll stiffness respectively.

[0177] S414. Calculate and determine the passive roll moment distribution coefficient of the target vehicle based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, the front axle mass ratio, and the rear axle mass ratio.

[0178] Here, the passive rolling moment distribution coefficient of the target vehicle is used to describe the rolling moment distribution state at this time.

[0179] In one embodiment of the present application, during specific implementation, step S414 may include:

[0180] S4141. Based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness and the front axle mass ratio, calculate and determine the front axle distribution torque value corresponding to the active suspension of the target vehicle when it does not actively generate output force.

[0181] In an embodiment of the present application, the formula for calculating the front axle distribution torque value corresponding to the active suspension of the target vehicle when not actively generating output force is as follows.

[0182]

[0183] Among them, M f Indicates the front axle distribution torque value; and Respectively represent the front axle suspension roll stiffness and the rear axle suspension roll stiffness; m represents the vehicle mass; M cog Indicates the center of mass roll moment value; a y Indicates the lateral acceleration value; W f Indicates the front axle mass ratio.

[0184] S4142. Based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness and the rear axle mass ratio, calculate and determine the rear axle distribution torque value corresponding to the active suspension of the target vehicle when it does not actively generate output force.

[0185] In an embodiment of the present application, the formula for calculating the rear axle distribution torque value corresponding to the active suspension of the target vehicle when not actively generating output force is as follows.

[0186]

[0187] Among them, M r Indicates the rear axle distribution torque value; and Respectively represent the front axle suspension roll stiffness and the rear axle suspension roll stiffness; m represents the vehicle mass; M cog Indicates the mass center rolling moment value; a y Indicates the lateral acceleration value; W r Indicates the rear axle mass ratio.

[0188] S4143. Add the front axle distributed torque value and the rear axle distributed torque value to obtain an addition result, and determine the ratio between the front axle distributed torque value and the addition result as the passive roll torque distribution coefficient of the target vehicle.

[0189] In an embodiment of the present application, an expression for calculating the passive roll moment distribution coefficient of the target vehicle is as follows.

[0190]

[0191] Among them, λ pas represents the passive roll moment distribution coefficient; M f and M r They respectively represent the front axle distribution torque value and the rear axle distribution torque value corresponding to the active suspension of the target vehicle when it does not actively generate output force.

[0192] S420. When the preset numerical interval to which the yaw control coefficient belongs is the first preset numerical interval, based on the wheelbase value of the target vehicle, the yaw control coefficient, the active suspension roll moment value and the passive roll moment distribution coefficient, determine the control force output values of the left front active suspension, the right front active suspension, the left rear active suspension and the right rear active suspension of the target vehicle respectively in the first preset numerical interval.

[0193] In this step, when the yaw control coefficient belongs to the first preset numerical range, that is, the yaw control coefficient is greater than 0 and less than 1, the formulas for calculating the control force output values of the left front active suspension, right front active suspension, left rear active suspension and right rear active suspension of the target vehicle in the first preset numerical range are as follows.

[0194]

[0195] Wherein, F1, F2, F3 and F4 represent the control force output values of the left front active suspension, right front active suspension, left rear active suspension and right rear active suspension of the target vehicle respectively; λ pas represents the passive roll moment distribution coefficient; Indicates the active suspension roll moment value; λ actv represents the yaw control coefficient; L represents the wheelbase value of the target vehicle.

[0196] S430. When the preset numerical interval to which the yaw control coefficient belongs is the second preset numerical interval or the third preset numerical interval, based on the wheelbase value of the target vehicle, the active suspension roll moment value and the passive roll moment distribution coefficient, determine the control force output values of the left front active suspension, the right front active suspension, the left rear active suspension and the right rear active suspension of the target vehicle in the second preset numerical interval or the third preset numerical interval respectively.

[0197] In this step, when the yaw control coefficient belongs to the second preset numerical range, that is, the yaw control coefficient is less than or equal to 0, the formulas for calculating the control force output values of the left front active suspension, right front active suspension, left rear active suspension and right rear active suspension of the target vehicle in the second preset numerical range are as follows.

[0198]

[0199] Furthermore, when the yaw control coefficient belongs to the third preset numerical range, that is, the yaw control coefficient is greater than or equal to 1, the formulas for calculating the control force output values of the left front active suspension, right front active suspension, left rear active suspension and right rear active suspension of the target vehicle in the third preset numerical range are as follows.

[0200]

[0201] Wherein, F1, F2, F3 and F4 represent the control force output values of the left front active suspension, right front active suspension, left rear active suspension and right rear active suspension of the target vehicle respectively; λ pas represents the passive roll moment distribution coefficient; represents the roll moment value of the active suspension; L represents the wheelbase value of the target vehicle.

[0202] For example, see Figure 3 , Figure 3 A schematic diagram of a vehicle steering control trajectory provided by an embodiment of the present application. The trajectory of a target vehicle in a steering condition with a fixed 60° steering wheel angle and uniform acceleration is shown in FIG. Figure 3 As shown in the figure, the dotted line is the driving trajectory of the vehicle with the active suspension control turned off; the dashed line is the driving trajectory of the vehicle using the traditional fixed-parameter active suspension yaw control strategy, which can also be regarded as the ideal trajectory of neutral steering; the solid line is the driving trajectory of the vehicle after applying the active suspension control method for improving the vehicle yaw stability provided by the present invention.

[0203] like Figure 3 As shown in , under the control of the steering control method provided in the embodiment of the present application, the target vehicle's ability to track the desired yaw rate at low speed is consistent with that of fixed parameter yaw control, and can well maintain a neutral steering state without obvious overshoot or delay; near the marked point, the yaw rate tracking control overshoots due to the increase in gain, indicating that the control effect of the yaw motion can change with the vehicle speed, which can better meet the yaw stability control requirements at different vehicle speeds and further improve the vehicle's controllability during steering.

[0204] Further, from Figure 3It can be seen that when the vehicle is at low speed (before reaching the marked data point), the driving trajectory tends to oversteer. When the vehicle speed increases to a certain level (after reaching the marked data point), the driving trajectory tends to understeer. By changing the dead zone range that changes with the vehicle speed, the allowable degree of understeer and oversteer at different speeds is changed, thereby improving the safety and controllability of the vehicle during steering.

[0205] The steering control method for a vehicle active suspension provided in an embodiment of the present application obtains vehicle data during turning travel, determines the deviation between the vehicle's current yaw rate and the expected yaw rate corresponding to neutral steering, and thereby determines the vehicle's steering state. The method also replaces the fixed controller gain parameter and yaw rate deviation dead zone in traditional yaw control with parameters that vary with vehicle speed. Furthermore, the method calculates the yaw control coefficient and, in combination with the passive roll moment distribution coefficient and the roll moment, calculates the control force required by the active suspension and outputs it to the active suspension to implement yaw control. This improves the control effect on the vehicle's steering stability, thereby enhancing the vehicle's safety and handling during steering.

[0206] See also Figure 4 , Figure 4 This is a schematic diagram of the structure of a steering control device for a vehicle active suspension provided in an embodiment of the present application. Figure 4 As shown in , the steering control device 400 includes:

[0207] an expected calculation module 410 for obtaining, during a turning process of a target vehicle, driving speed data, a front wheel steering angle value, an actual yaw rate, and a lateral acceleration value of the target vehicle, and determining an expected yaw rate corresponding to the target vehicle based on the driving speed data and the front wheel steering angle value;

[0208] a deviation calculation module 420 for determining a yaw rate deviation value of the target vehicle based on a difference between an absolute value corresponding to the actual yaw rate and an absolute value corresponding to the desired yaw rate and a yaw rate deviation value dead band corresponding to the driving speed data, so as to determine a steering state of the target vehicle;

[0209] a yaw control module 430 for determining a yaw control coefficient of the target vehicle in each of the steering states based on the yaw rate deviation value and a control parameter corresponding to the steering state, and determining a preset value range to which the yaw control coefficient belongs;

[0210] The output control module 440 is used to determine, for each of the preset numerical intervals, a control force output value of the active suspension of the target vehicle within the preset numerical interval based on the yaw control coefficient and the lateral acceleration value, and control the active suspension to adjust the yaw motion state of the target vehicle according to the control force output value.

[0211] Furthermore, when the expectation calculation module 410 is used to determine the expected yaw rate corresponding to the target vehicle based on the driving speed data and the front wheel steering angle value, the expectation calculation module 410 is used to:

[0212] Determining a longitudinal speed value of the target vehicle from the driving speed data, and respectively determining a wheelbase value and an understeer parameter of the target vehicle from preset parameters of the target vehicle;

[0213] An expected yaw rate corresponding to the target vehicle is calculated and determined based on the longitudinal speed value, the front wheel steering angle value, the wheelbase value, and the understeer parameter.

[0214] Furthermore, when the deviation calculation module 420 is configured to determine the yaw rate deviation value of the target vehicle based on the difference between the absolute value corresponding to the actual yaw rate and the absolute value corresponding to the expected yaw rate and the yaw rate deviation value dead band corresponding to the driving speed data to determine the turning state of the target vehicle, the deviation calculation module 420 is configured to:

[0215] subtracting an absolute value corresponding to the actual yaw rate from an absolute value corresponding to the expected yaw rate to determine a difference between the actual yaw rate and the expected yaw rate;

[0216] comparing the difference with a yaw rate deviation dead zone corresponding to the driving speed data to obtain a comparison result;

[0217] For each comparison result, determining a yaw rate deviation value of the target vehicle under the comparison result based on the difference and a boundary parameter corresponding to the yaw rate deviation dead zone;

[0218] The steering state of the target vehicle is determined based on the positive and negative performances corresponding to the yaw rate deviation values.

[0219] Furthermore, when the deviation calculation module 420 is configured to determine, for each comparison result, the yaw rate deviation value of the target vehicle based on the difference value and the boundary parameter corresponding to the yaw rate deviation dead zone, the deviation calculation module 420 is configured to:

[0220] When the comparison result shows that the difference is greater than a first boundary parameter corresponding to the yaw rate deviation dead zone, determining the difference between the difference and the first boundary parameter as the yaw rate deviation value of the target vehicle under the comparison result;

[0221] When the comparison result shows that the difference is less than or equal to a first boundary parameter corresponding to the yaw rate deviation value dead zone and the difference is greater than or equal to a second boundary parameter corresponding to the yaw rate deviation value dead zone, determining a first preset value as the yaw rate deviation value of the target vehicle under the comparison result;

[0222] When the comparison result is that the difference is smaller than the second boundary parameter corresponding to the yaw rate deviation dead zone, the difference between the difference and the second boundary parameter is determined as the yaw rate deviation value of the target vehicle under the comparison result.

[0223] Furthermore, when the deviation calculation module 420 is used to determine the steering state of the target vehicle based on the positive and negative performance corresponding to the yaw rate deviation value, the deviation calculation module 420 is used to:

[0224] When the yaw rate deviation value is equal to a first preset value, determining that the steering state of the target vehicle is a neutral steering state;

[0225] When the yaw rate deviation value is positive, determining that the steering state of the target vehicle is an oversteering state;

[0226] When the yaw rate deviation value is negative, it is determined that the steering state of the target vehicle is an understeering state.

[0227] Furthermore, when the yaw control module 430 is configured to determine a yaw control coefficient of the target vehicle in each steering state based on the yaw rate deviation value and the control parameter corresponding to the steering state, and to determine a preset value range to which the yaw control coefficient belongs, the yaw control module 430 is configured to:

[0228] When the steering state is an understeering state, determining a yaw control coefficient of the target vehicle in the understeering state based on the yaw rate deviation value and a first control parameter corresponding to the understeering state;

[0229] When the steering state is a neutral steering state or an oversteering state, determining a yaw control coefficient of the target vehicle in the neutral steering state or the oversteering state based on the yaw rate deviation value and a second control parameter corresponding to the oversteering state;

[0230] The yaw control coefficient is compared with a first preset value and a second preset value respectively, and based on the comparison results, a preset value range to which the yaw control coefficient belongs is determined.

[0231] Furthermore, when the output control module 440 is configured to determine, for each preset numerical range, based on the yaw control coefficient and the lateral acceleration value, the control force output value of the active suspension of the target vehicle within the preset numerical range, the output control module 440 is configured to:

[0232] determining an active suspension roll moment value and a passive roll moment distribution coefficient of the target vehicle based on the lateral acceleration value and preset parameters of the target vehicle;

[0233] When the preset numerical interval to which the yaw control coefficient belongs is a first preset numerical interval, determining control force output values of a left front active suspension, a right front active suspension, a left rear active suspension, and a right rear active suspension of the target vehicle, respectively, within the first preset numerical interval based on the wheelbase value of the target vehicle, the yaw control coefficient, the active suspension roll moment value, and the passive roll moment distribution coefficient;

[0234] When the preset numerical interval to which the yaw control coefficient belongs is the second preset numerical interval or the third preset numerical interval, based on the wheelbase value of the target vehicle, the active suspension roll moment value and the passive roll moment distribution coefficient, the control force output values of the left front active suspension, the right front active suspension, the left rear active suspension and the right rear active suspension of the target vehicle are determined in the second preset numerical interval or the third preset numerical interval respectively.

[0235] Furthermore, when the output control module 440 is used to determine the active suspension roll moment value and the passive roll moment distribution coefficient of the target vehicle based on the lateral acceleration value and the preset parameters of the target vehicle, the output control module 440 is used to:

[0236] Determining the target vehicle's vehicle mass, sprung mass, front axle roll center height, rear axle roll center height, sprung mass center height, target roll angle, front axle suspension roll stiffness, rear axle suspension roll stiffness, front axle mass ratio, and rear axle mass ratio from the preset parameters of the target vehicle;

[0237] Calculating and determining a center-of-mass roll moment value of the target vehicle based on the lateral acceleration value, the gravitational acceleration at the location of the target vehicle, the sprung mass, the vehicle front axle roll center height value, the vehicle rear axle roll center height value, the sprung mass center-of-mass height value, and the target roll angle value;

[0238] Calculating and determining an active suspension roll moment value of the target vehicle based on the center of mass roll moment value, the target roll angle value, the front axle suspension roll stiffness, and the rear axle suspension roll stiffness;

[0239] The passive roll moment distribution coefficient of the target vehicle is calculated and determined based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, the front axle mass ratio and the rear axle mass ratio.

[0240] Furthermore, when the output control module 440 is used to calculate and determine the passive roll moment distribution coefficient of the target vehicle based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, the front axle mass ratio, and the rear axle mass ratio, the output control module 440 is used to:

[0241] Calculating and determining a front axle distributed torque value corresponding to the active suspension of the target vehicle when not actively generating an output force based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, and the front axle mass ratio;

[0242] Calculating and determining a rear axle distributed torque value corresponding to the active suspension of the target vehicle when not actively generating an output force based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, and the rear axle mass ratio;

[0243] The front axle distributed torque value and the rear axle distributed torque value are added to obtain an addition result, and the ratio between the front axle distributed torque value and the addition result is determined as the passive roll torque distribution coefficient of the target vehicle.

[0244] The steering control device for a vehicle active suspension provided in an embodiment of the present application obtains vehicle data during turning travel, determines the deviation between the vehicle's current yaw rate and the expected yaw rate corresponding to neutral steering, and thereby determines the vehicle's steering state. The device replaces the fixed controller gain parameter and yaw rate deviation dead zone in traditional yaw control with parameters that vary with vehicle speed. Furthermore, the device calculates the yaw control coefficient and, in combination with the passive roll moment distribution coefficient and the roll moment, calculates the control force required by the active suspension. The control force is then output to the active suspension to implement yaw control, thereby improving the control effect on the vehicle's steering stability and thereby enhancing the vehicle's safety and handling during steering.

[0245] See also Figure 5 , Figure 5 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Figure 5 As shown in FIG, the electronic device 500 includes a processor 510, a memory 520 and a bus 530.

[0246] The memory 520 stores machine-readable instructions executable by the processor 510. When the electronic device 500 is running, the processor 510 communicates with the memory 520 via the bus 530. When the machine-readable instructions are executed by the processor 510, the above-mentioned Figure 1 The steps of the steering control method for the vehicle active suspension in the method embodiment shown are specifically implemented in accordance with the method embodiment and will not be described in detail here.

[0247] The embodiment of the present application also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the computer program can execute the above-mentioned Figure 1 The steps of the steering control method for the vehicle active suspension in the method embodiment shown are specifically implemented in accordance with the method embodiment and will not be described in detail here.

[0248] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0249] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. There may be other division methods in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed may be through some communication interface, indirect coupling or communication connection of devices or units, which may be electrical, mechanical or other forms.

[0250] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0251] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0252] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0253] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The scope of protection of the present application is not limited thereto. Although the present application has been described in detail with reference to the above-mentioned embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the above-mentioned embodiments within the technical scope disclosed in the present application, or perform equivalent replacements for some of the technical features thereof. These modifications, changes, or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A steering control method for a vehicle active suspension, characterized in that: The steering control method comprises: During the turning process of the target vehicle, obtaining the target vehicle's driving speed data, front wheel steering angle value, actual yaw rate and lateral acceleration value, and determining the target vehicle's corresponding expected yaw rate based on the driving speed data and the front wheel steering angle value; determining a yaw rate deviation value of the target vehicle based on a difference between an absolute value corresponding to the actual yaw rate and an absolute value corresponding to the desired yaw rate and a yaw rate deviation value dead band corresponding to the driving speed data to determine a steering state of the target vehicle; determining a yaw control coefficient of the target vehicle in each of the steering states based on the yaw rate deviation value and a control parameter corresponding to the steering state, and determining a preset value range to which the yaw control coefficient belongs; For each of the preset numerical intervals, based on the yaw control coefficient and the lateral acceleration value, a control force output value of the active suspension of the target vehicle within the preset numerical interval is determined, and the active suspension is controlled to adjust the yaw motion state of the target vehicle according to the control force output value.

2. The method according to claim 1, characterized in that The determining, based on the driving speed data and the front wheel steering angle value, an expected yaw rate corresponding to the target vehicle includes: Determining a longitudinal speed value of the target vehicle from the driving speed data, and respectively determining a wheelbase value and an understeer parameter of the target vehicle from preset parameters of the target vehicle; An expected yaw rate corresponding to the target vehicle is calculated and determined based on the longitudinal speed value, the front wheel steering angle value, the wheelbase value, and the understeer parameter.

3. The method according to claim 1, characterized in that The determining of the yaw rate deviation value of the target vehicle based on the difference between the absolute value corresponding to the actual yaw rate and the absolute value corresponding to the expected yaw rate and a yaw rate deviation value dead zone corresponding to the driving speed data to determine the steering state of the target vehicle includes: subtracting an absolute value corresponding to the actual yaw rate from an absolute value corresponding to the expected yaw rate to determine a difference between the actual yaw rate and the expected yaw rate; comparing the difference with a yaw rate deviation dead zone corresponding to the driving speed data to obtain a comparison result; For each comparison result, determining a yaw rate deviation value of the target vehicle under the comparison result based on the difference and a boundary parameter corresponding to the yaw rate deviation dead zone; The steering state of the target vehicle is determined based on the positive and negative performances corresponding to the yaw rate deviation values.

4. The method according to claim 3, characterized in that The step of determining, for each comparison result, a yaw rate deviation value of the target vehicle based on the difference and a boundary parameter corresponding to the yaw rate deviation dead zone comprises: When the comparison result shows that the difference is greater than a first boundary parameter corresponding to the yaw rate deviation dead zone, determining the difference between the difference and the first boundary parameter as the yaw rate deviation value of the target vehicle under the comparison result; When the comparison result shows that the difference is less than or equal to a first boundary parameter corresponding to the yaw rate deviation value dead zone and the difference is greater than or equal to a second boundary parameter corresponding to the yaw rate deviation value dead zone, determining a first preset value as the yaw rate deviation value of the target vehicle under the comparison result; When the comparison result is that the difference is smaller than the second boundary parameter corresponding to the yaw rate deviation dead zone, the difference between the difference and the second boundary parameter is determined as the yaw rate deviation value of the target vehicle under the comparison result.

5. The method according to claim 3, characterized in that The determining the steering state of the target vehicle based on the positive and negative performance corresponding to the yaw rate deviation value includes: When the yaw rate deviation value is equal to a first preset value, determining that the steering state of the target vehicle is a neutral steering state; When the yaw rate deviation value is positive, determining that the steering state of the target vehicle is an oversteering state; When the yaw rate deviation value is negative, it is determined that the steering state of the target vehicle is an understeering state.

6. The method according to claim 1, characterized in that Determining a yaw control coefficient of the target vehicle in each of the steering states based on the yaw rate deviation value and the control parameter corresponding to the steering state, and determining a preset value range to which the yaw control coefficient belongs, includes: When the steering state is an understeering state, determining a yaw control coefficient of the target vehicle in the understeering state based on the yaw rate deviation value and a first control parameter corresponding to the understeering state; When the steering state is a neutral steering state or an oversteering state, determining a yaw control coefficient of the target vehicle in the neutral steering state or the oversteering state based on the yaw rate deviation value and a second control parameter corresponding to the oversteering state; The yaw control coefficient is compared with a first preset value and a second preset value respectively, and based on the comparison results, a preset value range to which the yaw control coefficient belongs is determined.

7. The method according to claim 1, characterized in that The step of determining, for each of the preset numerical intervals, a control force output value of the active suspension of the target vehicle within the preset numerical interval based on the yaw control coefficient and the lateral acceleration value, includes: determining an active suspension roll moment value and a passive roll moment distribution coefficient of the target vehicle based on the lateral acceleration value and preset parameters of the target vehicle; When the preset numerical interval to which the yaw control coefficient belongs is a first preset numerical interval, determining control force output values of a left front active suspension, a right front active suspension, a left rear active suspension, and a right rear active suspension of the target vehicle, respectively, within the first preset numerical interval based on the wheelbase value of the target vehicle, the yaw control coefficient, the active suspension roll moment value, and the passive roll moment distribution coefficient; When the preset numerical interval to which the yaw control coefficient belongs is the second preset numerical interval or the third preset numerical interval, based on the wheelbase value of the target vehicle, the active suspension roll moment value and the passive roll moment distribution coefficient, the control force output values of the left front active suspension, the right front active suspension, the left rear active suspension and the right rear active suspension of the target vehicle are determined in the second preset numerical interval or the third preset numerical interval respectively.

8. The method according to claim 7, characterized in that The determining, based on the lateral acceleration value and the preset parameters of the target vehicle, respectively, the active suspension roll moment value and the passive roll moment distribution coefficient of the target vehicle includes: Determining the target vehicle's vehicle mass, sprung mass, front axle roll center height, rear axle roll center height, sprung mass center height, target roll angle, front axle suspension roll stiffness, rear axle suspension roll stiffness, front axle mass ratio, and rear axle mass ratio from the preset parameters of the target vehicle; Calculating and determining a center-of-mass roll moment value of the target vehicle based on the lateral acceleration value, the gravitational acceleration at the location of the target vehicle, the sprung mass, the vehicle front axle roll center height value, the vehicle rear axle roll center height value, the sprung mass center-of-mass height value, and the target roll angle value; Calculating and determining an active suspension roll moment value of the target vehicle based on the center of mass roll moment value, the target roll angle value, the front axle suspension roll stiffness, and the rear axle suspension roll stiffness; The passive roll moment distribution coefficient of the target vehicle is calculated and determined based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, the front axle mass ratio and the rear axle mass ratio.

9. The method according to claim 8, characterized in that The calculating and determining the passive roll moment distribution coefficient of the target vehicle based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, the front axle mass ratio, and the rear axle mass ratio includes: Calculating and determining a front axle distributed torque value corresponding to the active suspension of the target vehicle when not actively generating an output force based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, and the front axle mass ratio; Calculating and determining a rear axle distributed torque value corresponding to the active suspension of the target vehicle when not actively generating an output force based on the lateral acceleration value, the vehicle mass, the center of mass roll moment value, the front axle suspension roll stiffness, the rear axle suspension roll stiffness, and the rear axle mass ratio; The front axle distributed torque value and the rear axle distributed torque value are added to obtain an addition result, and the ratio between the front axle distributed torque value and the addition result is determined as the passive roll torque distribution coefficient of the target vehicle.

10. A steering control device for a vehicle active suspension, characterized in that: The steering control device comprises: an expected calculation module, configured to obtain a driving speed data, a front wheel steering angle value, an actual yaw rate, and a lateral acceleration value of the target vehicle during the target vehicle's turning process, and determine an expected yaw rate corresponding to the target vehicle based on the driving speed data and the front wheel steering angle value; a deviation calculation module, configured to determine a yaw rate deviation value of the target vehicle based on a difference between an absolute value corresponding to the actual yaw rate and an absolute value corresponding to the desired yaw rate and a yaw rate deviation value dead band corresponding to the driving speed data, so as to determine a steering state of the target vehicle; a yaw control module, configured to determine a yaw control coefficient of the target vehicle in each of the steering states based on the yaw rate deviation value and a control parameter corresponding to the steering state, and to determine a preset value range to which the yaw control coefficient belongs; an output control module for determining, for each of the preset numerical intervals, a control force output value of the active suspension of the target vehicle within the preset numerical interval based on the yaw control coefficient and the lateral acceleration value, and controlling the active suspension to adjust the yaw motion state of the target vehicle according to the control force output value.

11. An electronic device, characterized in that: include: A processor, a memory and a bus, wherein the memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor and the memory communicate via the bus. When the processor is running, the machine-readable instructions execute the steps of the steering control method for the active suspension of a vehicle as described in any one of claims 1 to 9.

12. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the steering control method for a vehicle active suspension according to any one of claims 1 to 9 are executed.

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