Vehicle yaw stability control method and device, vehicle and medium

Abstract

The invention discloses a vehicle yaw stability control method and device, a vehicle and a medium, and the method comprises the steps: obtaining an actual vehicle state parameter and an ideal vehicle state parameter of the vehicle, and calculating a vehicle body stability factor according to the actual vehicle state parameter and the ideal vehicle state parameter, and whether the vehicle body stability factor is in a preset stability state interval or not is judged, the preset stability state interval comprises a plurality of different stability state intervals, and if the vehicle body stability factor is in the preset stability state interval, the vehicle yaw stability is adjusted according to an actuator corresponding to the interval where the vehicle body stability factor is located. According to the method, the vehicle body stability factors are compared with the multiple different stability state intervals by presetting the multiple different stability state intervals, accurate control over the vehicle yaw stability according to the actuators corresponding to the intervals is achieved, the control target of the whole vehicle level is met, and the stability of the vehicle is improved.

Description

Technical Field

[0001] The present invention relates to the field of vehicle control technology, and in particular to a vehicle yaw stability control method, device, vehicle and medium. Background Art

[0002] Vehicle yaw stability is an important performance that affects the safety of high-speed driving. When the vehicle encounters interference from external factors (such as side wind), driving on separated roads, high-speed emergency obstacle avoidance, etc., the vehicle will deviate from the ideal vehicle handling characteristics. In serious cases, the driver will lose control of the vehicle and be in a very dangerous situation. Therefore, the vehicle yaw stability control method has become one of the key research contents.

[0003] At present, the existing technical solutions usually use the yaw rate sensor, wheel speed sensor, Ax, Ay, etc. of the vehicle stability control system to obtain the current vehicle stability state, calculate the target yaw rate according to the steering wheel angle and vehicle speed information, and judge whether the vehicle is in understeering, oversteering or stable state according to the deviation between the current yaw rate and the target rate. If the vehicle is in an understeering or oversteering state, the state of the vehicle is improved by hydraulic braking or torque intervention feedback control. In the above scheme, only the needs of the system itself are considered for control, which makes the overall control target unclear, thereby affecting the stability of the vehicle and causing the vehicle to become yaw-instable. Summary of the invention

[0004] Based on this, it is necessary to provide a vehicle yaw stability control method, device, vehicle and medium to address the above technical problems, so as to solve the problem that the existing technical solutions cannot meet the control objectives at the vehicle level, resulting in poor stability of vehicle body control.

[0005] A first aspect of an embodiment of the present application provides a vehicle yaw stability control method, the vehicle yaw stability control method comprising:

[0006] Obtaining actual vehicle state parameters and ideal vehicle state parameters of the vehicle;

[0007] Calculating a vehicle body stability factor according to the actual vehicle state parameter and the ideal vehicle state parameter;

[0008] determining whether the vehicle body stability factor is in a preset stability state interval, wherein the preset stability state interval includes a plurality of different stability state intervals;

[0009] If the vehicle body stability factor is in the preset stability state interval, the vehicle yaw stability is adjusted by using an actuator corresponding to the interval.

[0010] The second aspect of the embodiments of the present application provides a vehicle yaw stability control device, which includes:

[0011] An acquisition module, configured to acquire the actual vehicle state parameters and the ideal vehicle state parameters of the vehicle;

[0012] A calculation module, configured to calculate a vehicle body stability factor according to the actual vehicle state parameters and the ideal vehicle state parameters;

[0013] A judgment module, configured to judge whether the vehicle body stability factor is within a preset stability state interval, and the preset stability state interval includes multiple different stability state intervals;

[0014] An adjustment module, configured to, if the vehicle body stability factor is within the preset stability state interval, adjust the vehicle yaw stability by using the actuator corresponding to the interval where it is located.

[0015] In a third aspect, an embodiment of the present invention provides a vehicle, which includes a controller and multiple actuators of different types. Among them, the multiple actuators are used to adjust the vehicle yaw stability, and when the controller executes a computer program, it implements the vehicle yaw stability control method described in the first aspect above.

[0016] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, which stores a computer program, and is characterized in that when the computer program is executed by a processor, it implements the vehicle yaw stability control method described in the first aspect above.

[0017] In summary, the present invention provides a vehicle yaw stability control method, device, vehicle and medium. By acquiring the actual vehicle state parameters and the ideal vehicle state parameters of the vehicle, and then calculating a vehicle body stability factor according to the actual vehicle state parameters and the ideal vehicle state parameters, it is judged whether the vehicle body stability factor is within a preset stability state interval, and the preset stability state interval includes multiple different stability state intervals. If the vehicle body stability factor is within the preset stability state interval, the vehicle yaw stability is adjusted by using the actuator corresponding to the interval where it is located. By presetting multiple different stability state intervals in the present invention, each stability state interval performs different functions, and then the vehicle body stability factor is compared with multiple different stability state intervals, realizing precise control of the vehicle yaw stability by using the actuator corresponding to the interval where it is located, meeting the control objectives at the vehicle level, and improving the stability of the vehicle. Description of the Drawings

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for the description of the embodiments of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0019] Figure 1 It is a schematic flowchart of a vehicle yaw stability control method provided by an embodiment of the present invention;

[0020] Figure 2 It is a schematic structural diagram of a vehicle yaw stability control device provided by an embodiment of the present invention;

[0021] Figure 3 It is a schematic structural diagram of a vehicle provided by an embodiment of the present invention. Detailed implementation manners

[0022] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0023] It should be understood that when used in the specification and claims of the present invention, the term "comprising" indicates the presence of the described features, wholes, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0024] It should also be understood that the term "and / or" as used in the specification and claims of the present invention refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0025] As used in the specification and claims of the present invention, the term "if" can be interpreted as "when", "once", "in response to determining", or "in response to detecting" according to the context. Similarly, the phrase "if determined" or "if detected [the described condition or event]" can be interpreted as meaning "once determined", "in response to determining", "once detected [the described condition or event]", or "in response to detecting [the described condition or event]" according to the context.

[0026] In addition, in the description of the specification and the appended claims of the present invention, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and should not be construed as indicating or implying relative importance.

[0027] The reference to "one embodiment" or "some embodiments" etc. described in the specification of the present invention means that a specific feature, structure or characteristic described in connection with that embodiment is included in one or more embodiments of the present invention. Thus, the statements "in one embodiment", "in some embodiments", "in other some embodiments", "in still other embodiments", etc. that appear in different places in this specification do not necessarily all refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in another way. The terms "comprising", "including", "having" and their variants all mean "including but not limited to", unless otherwise specifically emphasized in another way.

[0028] It should be understood that the magnitudes of the sequence numbers of the steps in the following embodiments do not mean the order of execution is prior or subsequent, and the execution order of each process should be determined according to its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present invention.

[0029] As Figure 1 shown, it is a schematic flow chart of a vehicle yaw stability control method provided by an embodiment of the present invention. The vehicle yaw stability control method may include the following steps:

[0030] S101: Obtain the actual vehicle state parameters and the ideal vehicle state parameters of the vehicle.

[0031] In step S101, the actual vehicle state parameters are the parameters of the vehicle affected by various factors during driving, and the ideal vehicle state parameters are the parameters of the vehicle not affected by various factors during driving.

[0032] As an optional embodiment, obtaining the actual vehicle state parameters and the ideal vehicle state parameters of the vehicle includes:

[0033] Obtain the sensor parameter information of the vehicle;

[0034] Input the sensor parameter information into a pre-established vehicle dynamics model and a target calculation vehicle model to obtain the actual vehicle state parameters output by the vehicle dynamics model and the ideal vehicle state parameters output by the target calculation vehicle model.

[0035] In this embodiment, since the vehicle is equipped with multiple sensors, such as lidar sensors, vision sensors, speed sensors, acceleration sensors, position sensors, radars, etc., and the sensor parameter information can be shared through the vehicle's controller, such as sharing the parameter information measured by the lidar sensor, the image parameter information detected by the vision sensor, the speed parameter information detected by the speed sensor, the acceleration parameter information detected by the acceleration sensor, the position parameter information detected by the position sensor, the detection parameter information of the radar, etc., therefore, this application obtains the sensor parameter information of the vehicle through the controller. Among them, the sensor parameter information can be one or more of wheel speed, yaw angular velocity, steering wheel angle, lateral acceleration, master cylinder pressure, and longitudinal acceleration. The controller can receive all the sensor parameter information reported by the vehicle. For example, the vehicle terminal reports its own sensor parameter information to the controller through the communication network.

[0036] It should be noted that the controller in the embodiment of this application can be an edge controller or a central controller. As the name implies, the edge controller is a controller closer to the edge end, such as being set beside the sensor to provide services nearby and improve the data response speed; relative to the edge vehicle, the central controller is set in the center and can provide services in a larger range and more.

[0037] It should be noted that in this embodiment, the vehicle includes family cars (such as small cars, compact cars, medium-sized cars, mid-large cars) and trucks, etc., and no specific limitations are made in this embodiment.

[0038] In the embodiment of this application, a vehicle dynamics model and a target calculation vehicle model need to be established in advance. Among them, the vehicle dynamics model is constructed according to the vehicle's external dimensions, model, various power parameters, etc. After obtaining the sensor parameter information, the sensor parameter information is input into the vehicle dynamics model and the target calculation vehicle model to obtain the actual vehicle state parameters output by the vehicle dynamics model and the ideal vehicle state parameters output by the target calculation vehicle model. It should be noted that the vehicle state parameters can be parameters characterizing the current driving condition of the vehicle, and the vehicle state parameters can include one or more of yaw angular velocity, vehicle center of mass sideslip angle, tire lateral force, and tire sideslip angle.

[0039] In this embodiment, when constructing the vehicle's overall vehicle dynamics model, it is necessary to ensure that the actual vehicle state parameters calculated in real time by the overall vehicle dynamics model are as consistent as possible with the ideal vehicle state parameters calculated by the target calculation vehicle model, so as to ensure that the error is within an acceptable range. If the calculation deviation of the overall vehicle dynamics model is too large, it may lead to deviation in the accuracy of the calculated stability factor, resulting in inaccurate subsequent control of vehicle stability. To ensure this, the present invention fully and comprehensively considers the driving factors affecting vehicle operation in the real scenario, including: traction force, braking force, vehicle weight, vehicle length, friction damping, wind resistance, slope, etc. influencing factors, in order to construct an overall vehicle dynamics model that meets the requirements of calculation accuracy. For example, a 15-degree-of-freedom dynamics model can be used for solution. Among them, the 15-degree-of-freedom dynamics model is a mathematical model used to describe the motion of a multi-body system. It contains 15 degrees of freedom, that is, 15 independent coordinate and velocity variables. This model can be used to study various physical systems, such as molecules, atoms, solids, liquids, etc. In this model, each degree of freedom corresponds to an energy term and a momentum term, and their changes vary with time, thus describing the motion state of the system. The establishment of this model needs to consider various factors, such as mass, potential energy, kinetic energy, inertia, etc. Therefore, it is a relatively complex model.

[0040] It should be noted that the above methods for establishing the overall vehicle dynamics model and the target calculation vehicle model are only one possible implementation method. In other embodiments, different methods can be used, and the present application does not limit this.

[0041] As an alternative embodiment, the target calculation vehicle model outputs the ideal vehicle state parameters in the following manner:

[0042] Obtain the vehicle speed information, steering angle information, and characteristic vehicle speed information of the vehicle;

[0043] According to the vehicle speed information, steering angle information, and characteristic vehicle speed information, calculate the reference value of the Ackermann yaw rate of the vehicle;

[0044] Perform weighted processing on the reference value of the Ackermann yaw rate of the vehicle to obtain the target value of the Ackermann yaw rate of the vehicle;

[0045] Preset the yaw rate limit value and yaw rate increment value of the vehicle in advance;

[0046] According to the yaw rate limit value and yaw rate increment value, correct the target value of the Ackermann yaw rate of the vehicle to obtain the target yaw rate, and use the target yaw rate as the ideal vehicle state parameter.

[0047] In an embodiment of the present application, the characteristic vehicle speed information can be calculated by obtaining the cornering stiffness information, the distance information from the center of mass to the front and rear axles, and the mass information in the vehicle sensor parameter information. Then, based on the vehicle speed information, the steering angle information, and the characteristic vehicle speed information in the vehicle sensor parameter information, the reference value of the Ackermann yaw angular velocity of the vehicle is calculated through the Ackermann equation. The Ackermann equation is a formula for calculating the steering angle of a vehicle, and the dimensional parameters of the steering mechanism can be obtained through an analytical solution method. The characteristic vehicle speed information and the reference value of the Ackermann yaw angular velocity are calculated by the following formula:

[0048]

[0049]

[0050] Wherein, vch represents the characteristic vehicle speed information; C V represents the cornering stiffness information of the front axle of the vehicle; C H represents the cornering stiffness information of the rear axle of the vehicle; l V represents the distance information from the center of mass of the vehicle to the front axle; l H represents the distance information from the center of mass of the vehicle to the rear axle; m represents the center of mass of the vehicle; l represents the wheelbase information of the vehicle; evGiSo represents the reference value of the Ackermann yaw angular velocity of the vehicle; v represents the vehicle speed information; δ represents the steering wheel steering angle information of the vehicle.

[0051] In an embodiment of the present application, after calculating the reference value of the Ackermann yaw angular velocity of the vehicle, considering the actual road surface gradient, the reference value of the Ackermann yaw angular velocity of the vehicle is weighted to obtain the target value of the Ackermann yaw angular velocity of the vehicle. Then, to ensure the stability of the vehicle, the yaw angular velocity of the vehicle should not be too large. The upper limit value of the yaw angular velocity of the whole vehicle takes the road transverse gradient as the input and considers the actual force condition of the vehicle, and then obtains the yaw angular velocity limit value of the vehicle determined by the maximum external force. During actual turning driving, the driver operates the steering wheel in real time. Considering the influence of the increase in the steering angle, the yaw angular velocity increment value of the vehicle is obtained. Considering that the different tire adhesions on the left and right wheels will affect the calculation of the target yaw angular velocity, the target value of the Ackermann yaw angular velocity of the vehicle is corrected according to the obtained yaw angular velocity limit value and the yaw angular velocity increment value, and finally the target yaw angular velocity is obtained. The target yaw angular velocity is used as the ideal vehicle state parameter and compared with the yaw angular velocity obtained from the subsequent actual vehicle state parameters.

[0052] In this embodiment, after the vehicle obtains the sensor parameter information of the vehicle in real time, a vehicle dynamics model and a target calculation vehicle model are established in advance, and the sensor parameter information is input into the models, so as to output the actual vehicle state parameters and the ideal vehicle state parameters, which lays a foundation for the accuracy of calculating the vehicle stability factor later. By improving the efficiency of obtaining the sensor parameter information in this way, the vehicle yaw stability is accurately controlled, ensuring the reliability of vehicle driving and extending the service life of the vehicle.

[0053] S102: Calculate the vehicle body stability factor according to the actual vehicle state parameters and the ideal vehicle state parameters.

[0054] In step S102, after obtaining the actual vehicle state parameters and the ideal vehicle state parameters, the difference between the actual vehicle state parameters and the ideal vehicle state parameters is calculated to obtain the vehicle body stability factor of the actual vehicle state parameters compared with the ideal vehicle state parameters.

[0055] As an alternative embodiment, obtaining the vehicle body stability factor includes:

[0056] Compare the difference between the actual vehicle state parameters and the ideal vehicle state parameters;

[0057] According to the difference between the actual vehicle state parameters and the ideal vehicle state parameters, calculate the oversteer stability factor, the understeer stability factor and the large sideslip angle stability factor respectively;

[0058] According to the oversteer stability factor, the understeer stability factor, the large sideslip angle stability factor and the weight coefficient corresponding to each stability factor respectively, calculate the vehicle body stability factor, where the weight coefficient is obtained by analyzing the influence degree of each stability factor on the vehicle yaw stability.

[0059] In the embodiment of the present application, the actual vehicle state parameters and the ideal vehicle state parameters are compared in advance, the difference between the two is compared, and then according to the difference between the actual vehicle state parameters and the ideal vehicle state parameters, the oversteer stability factor, the understeer stability factor and the large sideslip angle stability factor are calculated respectively, and they are calculated by the following formulas respectively:

[0060] Koslsoueb 1 = min(1, A(abs(evGi)+0.5Δ)

[0061]

[0062] Koslsoβ = min(1, C(xβ + ydβ))

[0063] Among them, Koslsoueb 1 is expressed as the oversteer stability factor; A is expressed as a coefficient related to the vehicle speed, which needs to be calibrated through actual vehicle tests; abs(evGi) is expressed as the absolute value of the yaw rate deviation; Δ is expressed as the control deviation dead zone, which needs to be calibrated through actual vehicle tests; Koslsoueb 2 is expressed as the understeer stability factor; vGiSo is expressed as the target yaw rate; B is expressed as a coefficient related to the vehicle speed, which needs to be calibrated through actual vehicle tests; Koslsoβ is expressed as the large sideslip angle stability factor; C is expressed as a coefficient related to the vehicle speed, which needs to be calibrated through actual vehicle tests; β is expressed as the actual sideslip angle of the center of mass, obtained through model observation; x is expressed as a coefficient related to the sideslip angle of the center of mass; dβ is expressed as a coefficient related to the change rate of the sideslip angle of the center of mass.

[0064] In the embodiment of the present application, after calculating the oversteer stability factor, understeer stability factor, and large sideslip angle stability factor of the center of mass, then according to the weight coefficients corresponding to the oversteer stability factor, understeer stability factor, and large sideslip angle stability factor of the center of mass respectively, the vehicle body stability factor is further calculated, where the vehicle body stability factor is calculated by the following formula:

[0065] Koslso = min(1, abs(k1 * Koslsoueb 1 + k2 * Koslsoueb 2 + k3 * Koslsoβ))

[0066] Among them, Koslso is expressed as the vehicle body stability factor; Koslsoueb 1 is expressed as the oversteer stability factor; Koslsoueb 2 is expressed as the understeer stability factor; Koslsoβ is expressed as the large sideslip angle stability factor of the center of mass; k1 is expressed as the weight coefficient corresponding to the oversteer stability factor; k2 is expressed as the weight coefficient corresponding to the understeer stability factor; k3 is expressed as the weight coefficient corresponding to the large sideslip angle stability factor of the center of mass; among them, the weight coefficients are obtained through an analysis of the influence degree of each stability factor on the yaw stability of the vehicle.

[0067] In the embodiments of the present application, since different stability factors have different degrees of influence on vehicle yaw stability, different weight coefficients are assigned to different stability factors in this embodiment to represent the influence degrees of various stability factors on vehicle yaw stability. As an implementation manner, the variation relationship between vehicle yaw stability and road conditions can be separately statistically analyzed for each stability factor under continuous abnormal conditions, and the weight coefficient corresponding to each stability factor can be obtained through big data analysis of this variation relationship. In actual application scenarios, since the influence degree of each stability factor on vehicle yaw stability may change in different driving environments, and the variation relationship between vehicle yaw stability and road conditions may be a non-linear relationship, the corresponding weight coefficients of various stability factors may change.

[0068] In this embodiment, by using different stability factors and their corresponding weight coefficients, the body stability factor of the actual vehicle state parameters compared with the ideal vehicle state parameters can be accurately calculated, so as to accurately control the vehicle yaw stability according to the body stability factor in the subsequent steps.

[0069] S103: Determine whether the body stability factor is within a preset stability state interval, and the preset stability state interval includes multiple different stability state intervals.

[0070] In step S103, after obtaining the actual vehicle state parameters and the ideal vehicle state parameters, multiple stability state intervals can be set according to the difference degree between the actual vehicle state parameters and the ideal vehicle state parameters. Among them, each stability state interval includes entry and exit conditions, and then it is determined whether the body stability factor is within the stability state interval. If the body stability factor is within the stability state interval, step S104 is executed, that is, the vehicle yaw stability is adjusted by using the actuator corresponding to the interval where it is located. If the body stability factor is not within the stability state interval, the process ends, that is, the subsequent steps of the vehicle yaw stability control method will no longer be executed. Among them, the stability state intervals are as follows

[0071] as shown in Table 1:

[0072]

[0073] Table 1

[0074] In the embodiments of the present application, after calculating the vehicle body stability factor of the actual vehicle state parameters relative to the ideal vehicle state parameters as the basis for yaw stability control, the vehicle steering characteristics are determined by comparing the vehicle body stability factor with the upper limit values and threshold values of multiple pre-set stability state intervals, that is, in which stability state interval, so as to determine the yaw stability control intervention scheme. For example, if α1 < vehicle body stability factor < α2, it is determined that the vehicle is in the first stability state interval at this time, and then step S104 is entered; if σ1 < vehicle body stability factor < σ2, it is determined that the vehicle is in the second stability state interval at this time, and then step S104 is entered; if θ1 < vehicle body stability factor < θ2, it is determined that the vehicle is in the third stability state interval at this time, and then step S104 is entered; if ∈1 < vehicle body stability factor < ∈2, it is determined that the vehicle is in the fourth stability state interval at this time, and then step S104 is entered.

[0075] In this embodiment, by pre-setting multiple stability state intervals and comparing the vehicle body stability factor with the multiple stability state intervals, it is used as the basis for yaw stability control, which can adapt to different road surfaces, make the control instructions of the control system more accurate, and the stability control effect better.

[0076] S104: If the vehicle body stability factor is within the preset stability state interval, the yaw stability of the vehicle is adjusted by using the actuator corresponding to the interval.

[0077] In step S104, when the vehicle body stability factor is within the stability state interval, the yaw stability of the vehicle is adjusted by using the actuator corresponding to the interval. The actuators corresponding to each stability state interval are shown in Table 2 below:

[0078]

[0079] Table 2

[0080] As an alternative embodiment, adjusting the yaw stability of the vehicle by using the actuator corresponding to the interval includes:

[0081] If the vehicle body stability factor is within the first stability state interval, the suspension system is used to adjust the suspension damping and stiffness of the vehicle;

[0082] If the vehicle body stability factor is within the second stability state interval, the drive motor is used to adjust the drive torque of the vehicle;

[0083] If the vehicle body stability factor is within the third stability state interval, the yaw control system is used to perform yaw moment feedforward adjustment on the vehicle;

[0084] If the vehicle body stability factor is in the fourth stability state interval, a yaw control system is used to perform yaw moment feedback adjustment on the vehicle.

[0085] In the embodiment of the present application, when the vehicle body stability factor is in the stability state interval and meets the entry and exit conditions of the first stability state interval, that is, α1 < vehicle body stability factor < α2, at this time, it is determined that the vehicle is in the first stability state interval, and the suspension system is used to adjust the suspension damping and stiffness of the vehicle. That is, when it is necessary to reduce the understeer of the vehicle, the roll stiffness ratio of the rear axle is increased, and the yaw stability of the vehicle can be adjusted by simultaneously increasing the CDC damping force of the rear axle and the air suspension stiffness. When it is necessary to reduce the oversteer of the vehicle, the roll stiffness ratio of the front axle is increased, and the yaw stability of the vehicle can be adjusted by simultaneously increasing the CDC damping force of the front axle and the air suspension stiffness. When the vehicle body stability factor is in the stability state interval and meets the entry and exit conditions of the second stability state interval, that is, σ1 < vehicle body stability factor < σ2, at this time, it is determined that the vehicle is in the second stability state interval, and the drive motor is used to adjust the drive torque of the vehicle. That is, when it is necessary to reduce the under-torque steer of the vehicle, through active torque steer control, a yaw moment is generated to cancel or weaken the under-torque steer; when it is necessary to reduce the over-torque steer of the vehicle, through active torque steer control, a yaw moment is generated to cancel or weaken the over-torque steer. When the vehicle body stability factor is in the stability state interval and meets the entry and exit conditions of the third stability state interval, that is, θ1 < vehicle body stability factor < θ2, at this time, it is determined that the vehicle is in the third stability state interval, and the yaw control system is used to perform yaw moment feedforward adjustment on the vehicle. The deviation between the actual yaw angular velocity calculated by the comparison model and the target yaw angular velocity is compared, and the additional yaw moment is determined by using the PID algorithm or the LQR algorithm, and the yaw angular velocity is actively controlled and corrected by applying it to the corresponding wheels through differential braking. When the vehicle body stability factor is in the stability state interval and meets the entry and exit conditions of the fourth stability state interval, that is, ∈1 < vehicle body stability factor < ∈2, at this time, it is determined that the vehicle is in the fourth stability state interval, and the yaw control system is used to perform yaw moment feedback adjustment on the vehicle. The deviation between the actual yaw angular velocity calculated by the comparison model and the target yaw angular velocity is compared, and the additional yaw moment is determined by using the PID algorithm or the LQR algorithm, and the yaw angular velocity is actively controlled and corrected by applying it to the corresponding wheels through differential braking. It should be noted that the algorithms used are not limited to one type, and other algorithms can also be used. The present application makes no limitation on this.

[0086] In this embodiment, after determining whether the vehicle body stability factor is within the stability state interval, it is also necessary to determine whether the vehicle body stability factor meets the entry and exit conditions of each stability state interval. If the vehicle body stability factor meets the entry conditions of each stability state interval, the corresponding actuators are used for control and adjustment respectively. If the vehicle body stability factor meets the exit conditions of each stability state interval, the corresponding actuator control is executed to exit respectively. The present application proposes a specific method for hierarchical control according to stability, which ingeniously solves the problem of execution control coordination, can reduce the degree of complex coupling of the vehicle system, enables each interval to perform different functions, and makes the structural logic relationship clearer, facilitating the implementation of the functions of the vehicle control system and the expansion of later functions, and further realizing the precise control of the vehicle yaw stability.

[0087] In summary, the present invention provides a vehicle yaw stability control method, device, vehicle and medium. By obtaining the actual vehicle state parameters and ideal vehicle state parameters of the vehicle, and then calculating the vehicle body stability factor according to the actual vehicle state parameters and ideal vehicle state parameters, it is determined whether the vehicle body stability factor is within a preset stability state interval. The preset stability state interval includes a plurality of different stability state intervals. If the vehicle body stability factor is within the preset stability state interval, the vehicle yaw stability is adjusted by using the corresponding actuator in the interval where it is located. By presetting a plurality of different stability state intervals, the present invention enables each stability state interval to perform different functions, and then compares the vehicle body stability factor with a plurality of different stability state intervals, realizing the precise control of the vehicle yaw stability by using the corresponding actuator in the interval where it is located, meeting the control objectives at the vehicle level, and improving the stability of the vehicle.

[0088] Please refer to Figure 2 , Figure 2 which is a schematic structural diagram of a vehicle yaw stability control device provided by an embodiment of the present invention. In this embodiment, each module included in the device is used to execute Figure 1 the corresponding steps in the corresponding embodiment. Specifically, please refer to Figure 1 and Figure 1 the relevant descriptions in the corresponding embodiments. For the sake of convenience of description, only the parts related to this embodiment are shown. Refer to Figure 2 , the vehicle yaw stability control device 20 includes: an acquisition module 21, a calculation module 22, a judgment module 23, and an adjustment module 24.

[0089] The acquisition module 21 is used to acquire the actual vehicle state parameters and ideal vehicle state parameters of the vehicle;

[0090] The calculation module 22 is used to calculate the vehicle body stability factor according to the actual vehicle state parameters and the ideal vehicle state parameters;

[0091] A judgment module 23, configured to judge whether the vehicle body stability factor is within a preset stability state interval, and the preset stability state interval includes a plurality of different stability state intervals;

[0092] An adjustment module 24, configured to adjust the yaw stability of the vehicle by using an actuator corresponding to the interval where it is located if the vehicle body stability factor is within the preset stability state interval.

[0093] Optionally, the above-mentioned acquisition module 21 is specifically configured to:

[0094] Obtain sensor parameter information of the vehicle, where the sensor parameter information includes one or more of wheel speed, yaw angular velocity, steering wheel angle, lateral acceleration, master cylinder pressure, and longitudinal acceleration;

[0095] Input the sensor parameter information into a pre-established vehicle dynamics model and a target calculation vehicle model to obtain the actual vehicle state parameters output by the vehicle dynamics model and the ideal vehicle state parameters output by the target calculation vehicle model.

[0096] Optionally, the above-mentioned acquisition module 21 is further configured to:

[0097] Obtain the vehicle speed information, steering angle information, and characteristic vehicle speed information of the vehicle;

[0098] Calculate a reference value of the Ackermann yaw angular velocity of the vehicle according to the vehicle speed information, steering angle information, and characteristic vehicle speed information;

[0099] Perform a weighting process on the reference value of the Ackermann yaw angular velocity of the vehicle to obtain a target value of the Ackermann yaw angular velocity of the vehicle;

[0100] Preset a yaw angular velocity limit value and a yaw angular velocity increment value of the vehicle;

[0101] Correct the target value of the Ackermann yaw angular velocity of the vehicle according to the yaw angular velocity limit value and the yaw angular velocity increment value to obtain a target yaw angular velocity, and use the target yaw angular velocity as the ideal vehicle state parameter.

[0102] Optionally, the above-mentioned calculation module 22 is specifically configured to:

[0103] Compare the differences between the actual vehicle state parameters and the ideal vehicle state parameters;

[0104] Calculate an oversteer stability factor, an understeer stability factor, and a large sideslip angle stability factor respectively according to the differences between the actual vehicle state parameters and the ideal vehicle state parameters;

[0105] Based on the oversteer stability factor, understeer stability factor, and large sideslip angle stability factor of the vehicle and the weight coefficients corresponding to each stability factor respectively, a vehicle body stability factor is calculated, wherein the weight coefficients are obtained through an analysis of the influence degree of each stability factor on the yaw stability of the vehicle.

[0106] Optionally, the above-mentioned determination module 23 is specifically configured to:

[0107] Set a plurality of different stability state intervals according to the difference degree between the actual vehicle state parameters and the ideal vehicle state parameters.

[0108] Optionally, the above-mentioned adjustment module 24 is specifically configured to:

[0109] If the vehicle body stability factor is in the first stability state interval, the suspension system is used to adjust the suspension damping and stiffness of the vehicle;

[0110] If the vehicle body stability factor is in the second stability state interval, the drive motor is used to adjust the drive torque of the vehicle;

[0111] If the vehicle body stability factor is in the third stability state interval, the yaw control system is used to perform yaw moment feedforward adjustment on the vehicle;

[0112] If the vehicle body stability factor is in the fourth stability state interval, the yaw control system is used to perform yaw moment feedback adjustment on the vehicle.

[0113] It should be noted that for the information interaction, execution process, etc. between the above-mentioned modules, since they are based on the same concept as the method embodiment of the present invention, their specific functions and the technical effects brought thereby can be specifically referred to in the method embodiment part, and will not be elaborated here.

[0114] Figure 3 is a schematic structural diagram of a vehicle provided by an embodiment of the present invention. As Figure 3 shown, the vehicle of this embodiment includes a controller and a plurality of actuators of different types. Among them, the plurality of actuators are used to adjust the yaw stability of the vehicle. The controller includes a processor, a memory, and a computer program stored in the memory and executable on the processor. The processor of the vehicle is used to provide computing and control capabilities. The memory of the vehicle includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. When the computer program is executed by the processor, the steps in any of the above-mentioned vehicle yaw stability control method embodiments are implemented. When the processor of the vehicle executes the computer program, the following steps are implemented:

[0115] Obtain the actual vehicle state parameters and the ideal vehicle state parameters of the vehicle;

[0116] Calculate a vehicle body stability factor according to the actual vehicle state parameters and the ideal vehicle state parameters;

[0117] Determine whether the vehicle body stability factor is within a preset stability state interval, and the preset stability state interval includes a plurality of different stability state intervals;

[0118] If the vehicle body stability factor is within the preset stability state interval, adjust the vehicle yaw stability according to the actuator corresponding to the interval where it is located.

[0119] In one embodiment, a computer-readable storage medium is provided. When the instructions in the computer-readable storage medium are executed by a processor in the vehicle, the vehicle can execute each step of any embodiment of a vehicle yaw stability control method disclosed in the present invention, which will not be repeated here. The computer-readable storage medium may be non-volatile or volatile.

[0120] Those of ordinary skill in the art can understand that all or part of the processes of implementing the methods in the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, storage, database or other medium used in the embodiments provided in the present application can include non-volatile and / or volatile memories. Non-volatile memories can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memories can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0121] The so-called processor may be a CPU, and the processor may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc.

[0122] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the above division of each functional unit and module is used as an example. In actual applications, the above functions can be assigned to different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiments can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above integrated units can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of each functional unit and module are only for the convenience of mutual distinction and do not limit the protection scope of the present invention. The specific working processes of the units and modules in the above device can refer to the corresponding processes in the foregoing method embodiments and will not be repeated here. If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium.

[0123] The above-described embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention and should all be included in the protection scope of the present invention.

Claims

1. A vehicle yaw stability control method, characterized in that, it includes: Obtain the actual vehicle state parameters and ideal vehicle state parameters of the vehicle; Calculate a vehicle body stability factor based on the actual vehicle state parameters and the ideal vehicle state parameters; Determine whether the vehicle body stability factor is within a preset stability state interval, and the preset stability state interval includes multiple different stability state intervals; If the vehicle body stability factor is within the preset stability state interval, adjust the vehicle yaw stability by using the actuator corresponding to the interval where it is located.

2. The vehicle yaw stability control method according to claim 1, characterized in that, The preset stability state interval is determined by the following method: Set multiple different stability state intervals according to the degree of difference between the actual vehicle state parameters and the ideal vehicle state parameters.

3. The vehicle yaw stability control method according to claim 1, characterized in that, The step of if the vehicle body stability factor is within the preset stability state interval, then adjust the vehicle yaw stability by using the actuator corresponding to the interval where it is located, includes: If the vehicle body stability factor is within the first stability state interval, use the suspension system to adjust the suspension damping and stiffness of the vehicle; If the vehicle body stability factor is within the second stability state interval, use the drive motor to adjust the drive torque of the vehicle; If the vehicle body stability factor is within the third stability state interval, use the yaw control system to perform yaw moment feedforward adjustment on the vehicle; If the vehicle body stability factor is within the fourth stability state interval, use the yaw control system to perform yaw moment feedback adjustment on the vehicle.

4. The vehicle yaw stability control method according to claim 1, characterized in that, The step of calculating the vehicle body stability factor based on the actual vehicle state parameters and the ideal vehicle state parameters, includes: Compare the differences between the actual vehicle state parameters and the ideal vehicle state parameters; Calculate the oversteer stability factor, understeer stability factor, and large sideslip angle stability factor respectively according to the differences between the actual vehicle state parameters and the ideal vehicle state parameters; Calculate the vehicle body stability factor according to the oversteer stability factor, understeer stability factor, and large sideslip angle stability factor and the weight coefficients corresponding to each stability factor respectively, where the weight coefficients are obtained by analyzing the influence degree of each stability factor on the vehicle yaw stability.

5. The vehicle yaw stability control method according to claim 1, characterized in that, The step of obtaining the actual vehicle state parameters and ideal vehicle state parameters of the vehicle, includes: Obtain the sensor parameter information of the vehicle; Input the sensor parameter information into a pre-established vehicle dynamics model and a target calculation vehicle model to obtain the actual vehicle state parameters output by the vehicle dynamics model and the ideal vehicle state parameters output by the target calculation vehicle model.

6. The vehicle yaw stability control method according to claim 5, characterized in that, The target calculation vehicle model outputs ideal vehicle state parameters in the following manner: Obtain the vehicle speed information, steering angle information, and characteristic vehicle speed information of the vehicle; Calculate a reference value of the Ackermann yaw rate of the vehicle based on the vehicle speed information, steering angle information, and characteristic vehicle speed information; Perform a weighting process on the reference value of the Ackermann yaw rate of the vehicle to obtain a target value of the Ackermann yaw rate of the vehicle; Preset a yaw rate limit value and a yaw rate increment value of the vehicle in advance; Correct the target value of the Ackermann yaw rate of the vehicle according to the yaw rate limit value and the yaw rate increment value to obtain a target yaw rate, and use the target yaw rate as an ideal vehicle state parameter.

7. The vehicle yaw stability control method according to claim 5, wherein, the sensor parameter information includes one or more of wheel speed, yaw rate, steering wheel angle, lateral acceleration, master cylinder pressure, and longitudinal acceleration.

8. A vehicle yaw stability control device, wherein, it includes: an acquisition module for acquiring the actual vehicle state parameters and the ideal vehicle state parameters of the vehicle; a calculation module for calculating a vehicle body stability factor according to the actual vehicle state parameters and the ideal vehicle state parameters; a judgment module for judging whether the vehicle body stability factor is within a preset stability state interval, and the preset stability state interval includes a plurality of different stability state intervals; an adjustment module for, if the vehicle body stability factor is within the preset stability state interval, adjusting the vehicle yaw stability according to the actuator corresponding to the interval where it is located.

9. A vehicle, the vehicle includes a controller and a plurality of actuators of different types, wherein, the plurality of actuators are used to adjust the vehicle yaw stability, and when the controller executes a computer program, it implements the vehicle yaw stability control method according to any one of claims 1 to 7.

10. A computer-readable storage medium, the computer-readable storage medium stores a computer program, wherein, when the computer program is executed by a processor, it implements the vehicle yaw stability control method according to any one of claims 1 to 7.

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