Wheel state determination method and device, electronic equipment, storage medium and vehicle

Abstract

The invention provides a wheel state determination method and device, electronic equipment, a storage medium and a vehicle, and the method comprises the steps: obtaining an initial lateral deviation angle value of a wheel at a first moment; according to the ratio of the first difference value to the elastic lag time of the wheel, the slip angle change rate of the wheel at the first moment is determined; the first difference value is the difference value of the initial lateral deviation angle value relative to the lateral deviation angle value of the wheel at the second moment; the second moment is earlier than the first moment; and determining a target lateral deviation angle value of the wheel at the first moment according to the lateral deviation angle value of the wheel at the second moment and the slip angle change rate of the wheel at the first moment. According to the method, the influence of the elastic lag effect of the wheel on the wheel side slip angle is considered, the change rate of the wheel side slip angle is determined based on the initial side slip angle value and the elastic lag time of the wheel, and the target side slip angle value of the wheel is determined according to the change rate of the side slip angle, so that the accuracy of determining the wheel side slip angle can be improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a method, device, electronic device, storage medium and vehicle for determining a wheel state. Background Art

[0002] The wheel slip angle is an important parameter when the wheel contacts the ground. It can directly reflect the lateral movement state of the wheel. The accuracy of the wheel slip angle has an important influence on analyzing the vehicle's handling stability, optimizing the vehicle's suspension system, and improving the vehicle's driving safety.

[0003] However, currently most of them only consider the influence of the vehicle's lateral speed and the vehicle's longitudinal speed on the wheel slip angle, and directly determine the wheel slip angle based on the ratio of the vehicle's lateral speed to the vehicle's longitudinal speed. The accuracy of the wheel slip angle obtained by this method is poor. Summary of the invention

[0004] The main purpose of the embodiments of the present application is to propose a wheel state determination method, device, electronic device, storage medium and vehicle, aiming to improve the accuracy of determining the wheel slip angle.

[0005] The present application provides a method for determining a wheel state, comprising: obtaining an initial slip angle value of the wheel at a first moment; determining a slip angle change rate of the wheel at the first moment based on a ratio of a first difference value to an elastic lag time of the wheel; the first difference value is a difference between the initial slip angle value and a slip angle value of the wheel at a second moment; the second moment is earlier than the first moment; and determining a target slip angle value of the wheel at the first moment based on the slip angle value of the wheel at the second moment and the slip angle change rate.

[0006] In one embodiment, before determining the sideslip angle change rate of the wheel at the first moment based on the ratio of the first difference to the elastic lag time of the wheel, the wheel state determination method further includes: acquiring the lateral relaxation length of the wheel; and determining the elastic lag time based on the ratio of the lateral relaxation length to the value of the longitudinal speed of the vehicle at the first moment.

[0007] In one embodiment, obtaining the initial slip angle value of the wheel at the first moment includes: determining a first angle value between the pointing direction of the wheel at the first moment and the longitudinal direction of the vehicle at the first moment according to the product of the steering roll coefficient corresponding to the wheel and the target value of the roll angle of the vehicle at the first moment; determining a second angle value between the center of mass velocity direction of the wheel at the first moment and the longitudinal direction of the vehicle at the first moment according to the value of the longitudinal velocity of the vehicle at the first moment and the target values ​​of the lateral velocity and yaw velocity of the vehicle at the first moment using a kinematic formula; and determining a second difference between the first angle value and the second angle value as the initial slip angle value.

[0008] In one embodiment, the wheel state determination method also includes: obtaining the target motion condition of the vehicle at the first moment; obtaining the target motion condition of the vehicle at the first moment; obtaining a target method corresponding to the target motion condition and a value of a first state parameter at the first moment; wherein the target method includes at least one of a kinematic method and a dynamic method; when the target method includes the kinematic method, the first state parameter includes the longitudinal speed and front wheel angle of the vehicle; when the target method includes the dynamic method, the first state parameter includes the torque and lateral force of the vehicle; using the target method, according to the value of the first state parameter at the first moment, determining the initial value of the target state parameter of the vehicle at the first moment; wherein the target state parameters include yaw angular velocity, roll angle and lateral velocity; according to the initial value of the target state parameter at the first moment, determining the target value of the target state parameter at the first moment.

[0009] In one embodiment, when the target motion condition is a high-speed motion condition, the target method is the dynamic method; the use of the target method to determine the initial value of the target state parameter of the vehicle at the first moment according to the value of the first state parameter at the first moment includes: using the dynamic equilibrium equation corresponding to the first state parameter to determine the value of the second state parameter of the vehicle at the first moment according to the value of the first state parameter at the first moment; the second state parameter includes yaw angular acceleration, roll angular acceleration and lateral acceleration; determining the initial value of the target state parameter at the first moment according to the value of the target state parameter at the second moment and the value of the second state parameter at the first moment.

[0010] In one embodiment, after determining the target slip angle value of the wheel at the first moment, the wheel state determination method further includes: obtaining a brush tire model corresponding to the target slip angle value; and determining the lateral force value of the wheel at the first moment according to the target slip angle value using the brush tire model.

[0011] The present application also provides a wheel state determination device, comprising an acquisition module, a first determination module and a second determination module; the acquisition module is used to acquire an initial slip angle value of the wheel at a first moment; the first determination module is used to determine the slip angle change rate of the wheel at the first moment according to the ratio of a first difference to the elastic lag time of the wheel; the first difference is the difference between the initial slip angle value and the slip angle value of the wheel at a second moment; the second moment is earlier than the first moment; the second determination module is used to determine the target slip angle value of the wheel at the first moment according to the slip angle value of the wheel at the second moment and the slip angle change rate.

[0012] The present application also provides an electronic device, which includes a memory and a processor, wherein the memory stores a computer program, and the processor implements the above-mentioned wheel state determination method when executing the computer program.

[0013] The present application also provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the above-mentioned wheel state determination method is implemented.

[0014] The present application also provides a vehicle, which includes the above-mentioned electronic device.

[0015] The present application provides a wheel state determination method, device, electronic device, storage medium and vehicle, which take into account the influence of the elastic hysteresis effect of the wheel on the wheel slip angle, and on the basis of obtaining the initial slip angle value of the wheel, further determine the slip angle change rate of the wheel based on the initial slip angle value of the wheel and the elastic hysteresis time, and determine the target slip angle value of the wheel based on the slip angle change rate, which can improve the accuracy of determining the wheel slip angle. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The following is a flow chart of the wheel status determination method provided in the embodiment of the present application. Figure 1 ;

[0017] Figure 2 It is a schematic diagram of directions provided in an embodiment of the present application;

[0018] Figure 3 The following is a flow chart of the wheel status determination method provided in the embodiment of the present application. Figure 2 ;

[0019] Figure 4 is a schematic diagram of the structure of a wheel state determination device provided in an embodiment of the present application;

[0020] Figure 5 This is a schematic diagram of the structure of the electronic device provided in the embodiment of the present application. Figure 1 ;

[0021] Figure 6 This is a schematic diagram of the structure of the electronic device provided in the embodiment of the present application. Figure 2 . DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0023] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0024] The wheel state determination method provided in the embodiment of the present application can be applied to electronic devices, and can also be applied to the software of electronic devices. Among them, the electronic device can be a terminal or a server. In some embodiments, the terminal can be a smart phone, a tablet computer, a laptop computer, a desktop computer, etc.; the server can be configured as an independent physical server, or a server cluster or distributed system composed of multiple physical servers, and can also be configured as a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, CDN, and big data and artificial intelligence platforms. The software can be an application that implements the wheel state determination method, etc., but is not limited to the above forms.

[0025] The wheel state determination method provided in the embodiment of the present application is described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0026] See also Figure 1 , a wheel state determination method provided by an embodiment of the present application may include:

[0027] Step S101: obtaining an initial slip angle value of the wheel at a first moment;

[0028] Step S102: determining the slip angle change rate of the wheel at the first moment according to the ratio of the first difference to the elastic hysteresis time of the wheel; the first difference is the difference between the initial slip angle value and the slip angle value of the wheel at the second moment; the second moment is earlier than the first moment;

[0029] Step S103: determining a target slip angle value of the wheel at the first moment according to the slip angle value of the wheel at the second moment and the slip angle change rate of the wheel at the first moment.

[0030] The embodiment of the present application takes into account the influence of the elastic hysteresis effect of the wheel on the wheel slip angle. On the basis of obtaining the initial slip angle value of the wheel, the slip angle change rate of the wheel is further determined based on the initial slip angle value of the wheel and the elastic hysteresis time, and the target slip angle value of the wheel is determined based on the slip angle change rate, which can improve the accuracy of determining the wheel slip angle.

[0031] The first moment mentioned above can be the current moment or a historical moment. When the first moment mentioned above is the current moment, the wheel state determination method provided in the embodiment of the present application can determine the target slip angle value of the wheel at the current moment based on the relevant data acquired in real time; when the first moment mentioned above is a historical moment, the wheel state determination method provided in the embodiment of the present application can also determine the target slip angle value of the wheel at the historical moment based on the relevant historical data stored in advance.

[0032] The initial slip angle value in the above step S101 may be a calculated value or a sensor collected value. When the initial slip angle value is a calculated value, the initial slip angle value may be determined based on the ratio of the vehicle lateral speed to the vehicle longitudinal speed, or may be determined based on the product of the steering roll coefficient corresponding to the wheel and the vehicle roll angle. The present application does not limit the method for obtaining the initial slip angle value, as long as the determination principle of the wheel slip angle is met.

[0033] In one embodiment, the step S101 of obtaining the initial slip angle value of the wheel at the first moment includes:

[0034] Determine a first angle value between the pointing direction of the wheel at the first moment and the longitudinal direction of the vehicle at the first moment according to the product of the steering roll coefficient corresponding to the wheel and the target value of the roll angle of the vehicle at the first moment;

[0035] Determine, by using a kinematic formula, a second angle value between a center of mass velocity direction of the wheel at the first moment and a longitudinal direction of the vehicle at the first moment according to a value of the longitudinal velocity of the vehicle at the first moment and target values ​​of the lateral velocity and yaw velocity of the vehicle at the first moment;

[0036] A second difference between the first angle value and the second angle value is determined as an initial slip angle value.

[0037] See also Figure 2 , the direction of the wheel at the first moment represents the orientation of the wheel at the first moment, Figure 2 Medium Direction: The longitudinal direction of the vehicle at the first moment represents the orientation of the vehicle at the first moment. Figure 2 Medium Direction indicates that the wheel's center of mass velocity direction at the first moment represents the direction of the wheel's center of mass velocity at the first moment. Figure 2 Medium Direction indication.

[0038] Specifically, for the front wheels of the vehicle, the steering roll coefficient corresponding to the front wheels of the vehicle is the front steering roll coefficient of the vehicle. Formula (1) can be used to determine the first angle value between the pointing direction of the front wheels of the vehicle at the first moment and the longitudinal direction of the vehicle at the first moment:

[0039] δ f =C gamf *θ″ x +θ f (1)

[0040] Among them, δ f is the first angle between the pointing direction of the front wheel of the vehicle at the first moment and the longitudinal direction of the vehicle at the first moment, C gamf is the front steering roll coefficient of the vehicle, θ″ x is the target value of the vehicle's roll angle at the first moment, θ f is the value of the vehicle's front wheel angle at the first moment.

[0041] Formula (2) can be used to determine the second angle value between the center of mass velocity direction of the front wheel of the vehicle at the first moment and the longitudinal direction of the vehicle at the first moment:

[0042]

[0043] Among them, β f is the second angle value between the center of mass velocity direction of the front wheel of the vehicle at the first moment and the longitudinal direction of the vehicle at the first moment, V″ y is the target value of the vehicle’s lateral velocity at the first moment, V xis the longitudinal velocity of the vehicle at the first moment, W″ z is the target value of the vehicle’s yaw rate at the first moment, L f is the distance from the vehicle's center of mass to the vehicle's front axle.

[0044] Furthermore, formula (3) can be used to determine the initial slip angle value of the front wheel of the vehicle at the first moment:

[0045]

[0046] Among them, α f1 is the initial slip angle value of the vehicle's front wheel at the first moment.

[0047] Specifically, for the rear wheels of the vehicle, the steering roll coefficient corresponding to the rear wheels of the vehicle is the rear steering roll coefficient of the vehicle. Formula (4) can be used to determine the first angle value between the pointing direction of the rear wheels of the vehicle at the first moment and the longitudinal direction of the vehicle at the first moment:

[0048] δ r =C gamr *θ″ x (4)

[0049] Among them, δ r is the first angle between the pointing direction of the rear wheel of the vehicle at the first moment and the longitudinal direction of the vehicle at the first moment, C gamr is the rear steering roll coefficient of the vehicle.

[0050] Formula (5) can be used to determine the second angle value between the center of mass velocity direction of the rear wheel of the vehicle at the first moment and the longitudinal direction of the vehicle at the first moment:

[0051]

[0052] Among them, β r is the second angle between the center-of-mass velocity direction of the rear wheel of the vehicle at the first moment and the longitudinal direction of the vehicle at the first moment, L r is the distance from the vehicle's center of mass to the vehicle's rear axle.

[0053] Furthermore, formula (6) can be used to determine the initial slip angle value of the rear wheel of the vehicle at the first moment:

[0054]

[0055] Among them, α r1 is the initial slip angle value of the vehicle's rear wheel at the first moment.

[0056] Optionally, the target values ​​of the vehicle's roll angle, lateral velocity and yaw angular velocity at the first moment may be sensor collected values, or may be values ​​calculated based on a kinematic method and / or a dynamic method corresponding to the target motion condition of the vehicle at the first moment.

[0057] The embodiment of the present application takes into account the influence of the lateral force generated by the vehicle's rolling state on the wheel slip angle. Based on the target values ​​of the vehicle's lateral velocity, longitudinal velocity and yaw angular velocity at the first moment, the second angle value between the center of mass velocity direction of the wheel at the first moment and the longitudinal direction of the vehicle at the first moment is determined by using the kinematic formula. The first angle value between the pointing direction of the wheel at the first moment and the longitudinal direction of the vehicle at the first moment is determined by multiplying the steering roll coefficient corresponding to the wheel by the target value of the vehicle's roll angle at the first moment. The second difference between the first angle value and the second angle value is determined as the initial slip angle value of the wheel at the first moment, which can improve the accuracy of determining the wheel slip angle.

[0058] Optionally, the elastic hysteresis time of the wheel in the above step S102 can be obtained through experimental calibration, or can be calculated in real time based on the value of the longitudinal speed of the vehicle at the first moment.

[0059] In one embodiment, before determining the side slip angle change rate of the wheel at the first moment according to the ratio of the first difference to the elastic hysteresis time of the wheel in the above step S102, the wheel state determination method provided in the embodiment of the present application further includes:

[0060] Get the lateral slack length of the wheel;

[0061] The elastic hysteresis time is determined from the ratio of the lateral relaxation length to the value of the longitudinal speed of the vehicle at a first instant.

[0062] Optionally, the lateral slack length of the wheel is obtained by experimental calibration.

[0063] Specifically, the elastic hysteresis time of the wheel can be determined by using formula (7):

[0064]

[0065] Where ΔT is the elastic hysteresis time of the wheel, σ y is the lateral slack length of the wheel, V x is the value of the vehicle's longitudinal velocity at the first moment.

[0066] In actual implementation, the longitudinal velocity of the vehicle at the first moment V x and the lateral relaxation length σ of the vehicle's front wheels yf Substituting into formula (7), we can get the elastic hysteresis time ΔT of the front wheel of the vehicle:f ; You can also use the value of the vehicle's longitudinal velocity at the first moment V x and the lateral relaxation length σ of the vehicle's rear wheel yr Substituting into formula (7), we can get the elastic hysteresis time ΔT of the rear wheel of the vehicle: r .

[0067] It is worth mentioning that formula (7) is only an example of determining the elastic lag time based on the ratio of the lateral relaxation length to the longitudinal speed of the vehicle at the first moment. In actual implementation, coefficients can be multiplied on the basis of formula (7) to further improve the accuracy of determining the elastic lag time.

[0068] The embodiment of the present application can accurately determine the elastic lag time of the wheel based on the ratio of the lateral relaxation length of the wheel to the longitudinal speed of the vehicle at the first moment, thereby improving the accuracy of determining the target sideslip angle value of the wheel at the first moment based on the elastic lag time of the wheel.

[0069] Optionally, when the second moment in the above step S102 is the initial moment when the vehicle is powered on, the slip angle value of the above wheel at the second moment is 0.

[0070] Specifically, for the front wheel of the vehicle, formula (8) can be used to determine the difference between the initial slip angle value of the front wheel of the vehicle at the first moment and the slip angle value of the front wheel of the vehicle at the second moment:

[0071]

[0072] Among them, Δα f is the difference between the initial slip angle value of the front wheel of the vehicle at the first moment and the slip angle value of the front wheel of the vehicle at the second moment; α f ' 1 is the side slip angle value of the vehicle's front wheel at the second moment.

[0073] Furthermore, formula (9) can be used to determine the rate of change of the sideslip angle of the front wheel of the vehicle at the first moment:

[0074]

[0075] in, is the rate of change of the sideslip angle of the vehicle's front wheel at the first moment.

[0076] Specifically, for the rear wheel of the vehicle, formula (10) can be used to determine the difference between the initial slip angle value of the rear wheel of the vehicle at the first moment and the slip angle value of the rear wheel of the vehicle at the second moment:

[0077]

[0078] Among them, Δα r is the difference between the initial slip angle value of the rear wheel of the vehicle at the first moment and the slip angle value of the rear wheel of the vehicle at the second moment; α′ r1 is the slip angle value of the rear wheel of the vehicle at the second moment.

[0079] Furthermore, formula (11) can be used to determine the rate of change of the sideslip angle of the rear wheel of the vehicle at the first moment:

[0080]

[0081] in, is the rate of change of the sideslip angle of the rear wheel of the vehicle at the first moment.

[0082] It is worth mentioning that the above formulas (9) and (11) are only examples of determining the rate of change of the sideslip angle of the wheel at the first moment based on the ratio of the first difference to the elastic lag time of the wheel. In actual implementation, coefficients can be multiplied on the basis of formulas (9) and (11) to further improve the accuracy of determining the rate of change of the sideslip angle of the wheel at the first moment.

[0083] In one embodiment, step S103: determining a target slip angle value of the wheel at the first moment according to the slip angle value of the wheel at the second moment and the slip angle change rate, comprises:

[0084] The target slip angle value of the wheel at the first moment is determined by using the integration method according to the slip angle value of the wheel at the second moment and the slip angle change rate.

[0085] Specifically, for the front wheel of the vehicle, formula (12) can be used to determine the target slip angle value of the front wheel of the vehicle at the first moment:

[0086]

[0087] Among them, α″ f1 is the target slip angle value of the front wheel of the vehicle at the first moment, and Ts is a preset time interval, which is equal to the interval between the first moment and the second moment.

[0088] For the rear wheels of the vehicle, formula (13) can be used to determine the target slip angle value of the rear wheels of the vehicle at the first moment:

[0089]

[0090] Among them, α″ r1 is the target slip angle value of the vehicle's rear wheels at the first moment.

[0091] The embodiment of the present application uses the integration method to determine the target slip angle value of the wheel at the first moment based on the slip angle value of the wheel at the second moment and the slip angle change rate, which can reduce the influence of the input instantaneous value on the calculation result of the wheel slip angle, and thus can improve the accuracy of determining the wheel slip angle.

[0092] See also Figure 3 , a wheel state determination method provided by an embodiment of the present application may further include:

[0093] Step S201: obtaining an initial slip angle value of the wheel at the first moment;

[0094] Step S202: determining the slip angle change rate of the wheel at the first moment according to the ratio of the first difference to the elastic hysteresis time of the wheel; the first difference is the difference between the initial slip angle value and the slip angle value of the wheel at the second moment; the second moment is earlier than the first moment;

[0095] Step S203: determining a target slip angle value of the wheel at the first moment according to the slip angle value of the wheel at the second moment and the slip angle change rate of the wheel at the first moment;

[0096] Step S204: determining the lateral force value of the wheel at the first moment according to the target slip angle value of the wheel at the first moment.

[0097] The implementation process of step S201 to step S203 is the same as the implementation process of step S101 to step S103, which will not be repeated here.

[0098] The above step S204: determining the lateral force value of the wheel at the first moment according to the target slip angle value of the wheel at the first moment may include:

[0099] Get the brush tire model corresponding to the target slip angle value;

[0100] The brush tire model is used to determine the lateral force value of the wheel at the first moment according to the target slip angle value.

[0101] Specifically, for the front wheels of the vehicle, In the case of , the lateral force value of the front wheel of the vehicle at the first moment can be determined based on the brush tire model shown in formula (14):

[0102]

[0103] exist In the case of , the lateral force value of the wheel at the first moment can be determined based on the brush tire model shown in formula (15):

[0104] F yf1 =F zf1*μ*sign(α″ f1 ) (15)

[0105] Among them, F yf1 is the lateral force value of the front wheel of the vehicle at the first moment, F zf1 is the target value of the vertical force on the front wheels of the vehicle at the first moment, g is the acceleration due to gravity, μ is the road adhesion coefficient, ms is the sprung mass of the vehicle, mu is the unsprung mass of the vehicle, and sign is the sign function.

[0106] For the rear wheels of the vehicle, In the case of , the lateral force value of the rear wheel of the vehicle at the first moment can be determined based on the brush tire model shown in formula (16):

[0107]

[0108] exist In the case of , the target slip angle value of the rear wheel of the vehicle at the first moment can be determined based on the brush tire model shown in formula (17):

[0109] F yr1 =F zr1 *μ*sign(α″ r1 ) (17)

[0110] Among them, F yr1 is the lateral force value of the rear wheel of the vehicle at the first moment, F zr1 is the target value of the vertical force on the rear wheels of the vehicle at the first moment.

[0111] The embodiment of the present application takes into account the influence of the elastic hysteresis effect of the wheel on the slip angle of the wheel. By obtaining the initial slip angle value of the wheel, and determining the slip angle change rate of the wheel based on the initial slip angle value of the wheel and the elastic hysteresis time, and accurately determining the target slip angle value of the wheel based on the slip angle change rate, the brush tire model corresponding to the target slip angle value is further used to accurately determine the lateral force value of the wheel based on the target slip angle value of the wheel.

[0112] In one implementation, the wheel state determination method provided in the embodiment of the present application further includes:

[0113] Obtain the target motion condition of the vehicle at the first moment;

[0114] Obtaining a target motion condition of the vehicle at a first moment; obtaining a target method and a value of a first state parameter at the first moment corresponding to the target motion condition; wherein the target method includes at least one of a kinematic method and a dynamic method; when the target method includes a kinematic method, the first state parameter includes a longitudinal speed and a front wheel angle of the vehicle; when the target method includes a dynamic method, the first state parameter includes a torque and a lateral force of the vehicle;

[0115] Using a target method, according to the value of the first state parameter at the first moment, an initial value of a target state parameter of the vehicle at the first moment is determined; wherein the target state parameter includes a yaw angular velocity, a roll angle, and a lateral velocity;

[0116] According to the initial value of the target state parameter at the first moment, a target value of the target state parameter at the first moment is determined.

[0117] The embodiment of the present application obtains the target motion condition of the vehicle at the first moment, and adopts the target method corresponding to the target motion condition to determine the target value of the target state parameter of the vehicle at the first moment based on the value of the first state parameter corresponding to the target motion condition at the first moment. The target value of the target state parameter of the vehicle at the first moment can be accurately determined for different motion conditions of the vehicle, thereby improving the accuracy of determining the target sideslip angle value and lateral force value of the wheel at the first moment based on the target value of the target state parameter of the vehicle at the first moment.

[0118] The target motion condition can be a target motion condition related to vehicle speed or a target motion condition related to road surface flatness. It is worth mentioning that the present application does not limit the motion condition to which the target motion condition belongs, and the motion condition to which the target motion condition belongs only needs to conform to the actual motion condition of the vehicle. The motion condition related to vehicle speed can include high-speed motion condition, medium-speed motion condition and low-speed motion condition. Furthermore, the target motion condition of the vehicle at the first moment can be determined based on the relationship between the value of the longitudinal speed of the vehicle at the first moment and the preset speed value, or based on the relationship between the value of the motor speed or engine speed of the vehicle at the first moment and the preset speed value. The target motion condition of the vehicle at the first moment can also be determined based on the driving position of the vehicle at the first moment. If the driving position of the vehicle at the first moment is on a high-speed section, then the target motion condition of the vehicle at the first moment can be determined to be a high-speed motion condition. If the driving position of the vehicle at the first moment is on a non-high-speed section and the congestion level of the driving position is higher than the preset level, then the target motion condition of the vehicle at the first moment can be determined to be a low-speed motion condition. If the driving position of the vehicle at the first moment is on a non-high-speed section and the congestion level of the driving position is less than or equal to the preset level, then the target motion condition of the vehicle at the first moment can be determined to be a medium-speed motion condition.

[0119] The above-mentioned first moment can be the current moment or a historical moment. In the case where the above-mentioned first moment is the current moment, the wheel state determination method provided in the embodiment of the present application can determine the target value of the target state parameter of the vehicle at the current moment, as well as the target slip angle value and lateral force value of the wheel at the current moment based on the relevant data acquired in real time; in the case where the above-mentioned first moment is a historical moment, the wheel state determination method provided in the embodiment of the present application can also determine the target value of the target state parameter of the vehicle at a historical moment, as well as the target slip angle value and lateral force value of the wheel at a historical moment based on the relevant historical data stored in advance.

[0120] Optionally, when the target motion condition is a high-speed motion condition, the target method is a dynamic method. When the target motion condition is a low-speed motion condition, the target motion method is a kinematic method. When the target motion condition is a medium-speed motion condition, the target motion method is a kinematic method and a dynamic method.

[0121] Specifically, when the target motion condition is a low-speed motion condition, the overall dynamic characteristics of the vehicle are not obvious, but it can satisfy the assumption that the front wheel speed of the vehicle only exists in the direction of the front wheel turning angle, so the kinematic method can be used to accurately determine the value of the target state parameter at the first moment; when the target motion condition is a high-speed motion condition, the overall dynamic characteristics of the vehicle are obvious, and it no longer satisfies the assumption that the front wheel speed of the vehicle only exists in the direction of the front wheel turning angle, and the error of using the kinematic method to determine the value of the target state parameter at the first moment is large, so the dynamic method can be used to accurately determine the value of the target state parameter at the first moment; when the target motion condition is a medium-speed motion condition, the overall dynamic characteristics of the vehicle are obvious, and it can satisfy the assumption that the front wheel speed of the vehicle only exists in the direction of the front wheel turning angle, so the method of combining the kinematic method and the dynamic method can be used to accurately determine the value of the target state parameter at the first moment.

[0122] Optionally, the preset speed value includes a first preset speed value and a second preset speed value, and the second preset speed value is greater than the first preset speed value.

[0123] In one embodiment, the obtaining of the target motion condition of the vehicle at the first moment includes:

[0124] Get the value of the longitudinal velocity of the vehicle at the first moment;

[0125] When the longitudinal speed at the first moment is less than the first preset speed value, the target motion condition is a low-speed motion condition; and the target method is a kinematic method;

[0126] When the longitudinal speed at the first moment is greater than the second preset speed value, the target motion condition is a high-speed motion condition; and the target method is a dynamic method;

[0127] When the value of the longitudinal speed at the first moment is within the first target interval, the target motion condition is a medium-speed motion condition; the target method is a kinematic method and a dynamic method; and the first target interval is a closed interval consisting of a first preset speed value and a second preset speed value.

[0128] The first preset speed value and the second preset speed value can be obtained by calibration according to actual needs. Optionally, the first preset speed value is 10 kph and the second preset speed value is 15 kph.

[0129] The embodiment of the present application compares the value of the longitudinal speed at the first moment with the first preset speed value and the second preset speed value, and determines the target motion condition of the vehicle at the first moment based on the comparison result, thereby improving the accuracy of determining the target motion condition of the vehicle at the first moment, and further improving the accuracy of determining the values ​​of the target state parameters of the vehicle for the target motion condition, thereby improving the accuracy of determining the target sideslip angle value and lateral force value of the wheel based on the target state parameter values ​​of the vehicle.

[0130] Optionally, the torque of the vehicle mentioned above includes the yaw torque of the vehicle and the roll torque of the vehicle.

[0131] In one embodiment, when the target method includes a dynamic method, the target method corresponding to the target motion condition and the value of the first state parameter at the first moment are obtained, including:

[0132] Based on the generation principle of the vehicle lateral force, the value of the lateral force at the first moment is determined according to the value of the third state parameter of the vehicle at the first moment and the value of the yaw angular velocity at the second moment; the third state parameter includes the longitudinal velocity, the front axle lateral force, the rear axle lateral force, the front axle longitudinal force and the front wheel turning angle;

[0133] Determine the value of the yaw torque at the first moment according to the values ​​of the longitudinal force of the wheels and the front wheel angle of the vehicle at the first moment by using the mechanical relationship of the vehicle in the first plane;

[0134] The value of the roll torque at the first moment is determined by utilizing the mechanical relationship of the vehicle in the second plane, according to the values ​​of the yaw angular velocity, the roll angular velocity and the roll angle at the second moment, and the value of the longitudinal velocity at the first moment; wherein the first plane is parallel to the road surface on which the vehicle is traveling at the first moment; and the second plane is perpendicular to the road surface on which the vehicle is traveling at the first moment.

[0135] Specifically, based on the generation principle of the vehicle lateral force, the value of the vehicle lateral force at the first moment can be determined using formula (18):

[0136] F y =F yf *cosθ f +F yr +m*V x *W z '+F xf *sinθ f (18)

[0137] Among them, F y is the value of the vehicle's lateral force at the first moment, F yf is the value of the lateral force on the front axle of the vehicle at the first moment, F yr is the value of the rear axle lateral force of the vehicle at the first moment, F xf is the value of the front axle longitudinal force of the vehicle at the first moment, m is the total mass of the vehicle, V x is the longitudinal velocity of the vehicle at the first moment, W z ' is the value of the vehicle's yaw rate at the second moment, θ f is the value of the vehicle's front wheel angle at the first moment.

[0138] Among them, F xf It is equal to the sum of the longitudinal forces of the left front wheel and the right front wheel at the first moment; F yf 、F yr Can be determined using the brush tire model.

[0139] Specifically, in In the case of yf :

[0140]

[0141] exist In the case of yf :

[0142] F yf =F zf *μ*sign(α f ) (20)

[0143] exist In the case of yr :

[0144]

[0145] exist In the case of yr :

[0146] F yr =F zr *μ*sign(α r ) (twenty two)

[0147] Among them, α f , α r are the values ​​of the front and rear axle slip angles of the vehicle at the first moment, F zf 、F zr are the values ​​of the vertical forces on the front and rear axles of the vehicle at the first moment, C f , C r are the front and rear axle cornering stiffness of the vehicle, L f , L r are the distances from the center of mass of the vehicle to the front and rear axles respectively, g is the acceleration of gravity, μ is the road adhesion coefficient, ms is the sprung mass of the vehicle, mu is the unsprung mass of the vehicle, and sign is the sign function.

[0148] Specifically, the mechanical relationship of the vehicle in the first plane can be used to determine the value of the yaw torque of the vehicle at the first moment using formula (23):

[0149]

[0150] Among them, M z is the value of the vehicle's yaw torque at the first moment, F xFL 、F xFR 、F xRL 、F xRR are the values ​​of the left front wheel longitudinal force, right front wheel longitudinal force, left rear wheel longitudinal force, and right rear wheel longitudinal force of the vehicle at the first moment, respectively, f , W r are the lengths of the front and rear axles of the vehicle respectively.

[0151] Specifically, the mechanical relationship of the vehicle in the second plane can be used to determine the value of the vehicle's roll torque at the first moment using formula (24):

[0152] M x =ms*V x *W z '*hs+ms*g*sinθ′ x *hs-K d *θ x2 -D d *W x ' (twenty four)

[0153] Among them, M x is the value of the vehicle's roll torque at the first moment, θ′ x is the value of the vehicle's roll angle at the second moment, W x' is the value of the vehicle's roll angular velocity at the second moment, hs is the height of the vehicle's center of mass relative to the X-axis of the vehicle body coordinate system, K d is the vehicle's roll stiffness coefficient, D d is the roll damping coefficient of the vehicle. Optionally, the X-axis of the vehicle body coordinate system is located on the plane where the wheels contact the ground, and the X-axis direction is the longitudinal direction of the vehicle.

[0154] The embodiment of the present application is based on the principle of generating the lateral force of the vehicle. According to the value of the third state parameter of the vehicle at the first moment and the value of the yaw angular velocity at the second moment, the value of the lateral force of the vehicle at the first moment can be accurately determined. By utilizing the mechanical relationship of the vehicle in the first plane, according to the values ​​of the longitudinal force of the vehicle wheels and the front wheel angle at the first moment, the value of the yaw torque of the vehicle at the first moment can be accurately determined. By utilizing the mechanical relationship of the vehicle in the second plane, according to the values ​​of the yaw angular velocity, the roll angular velocity and the roll angle at the second moment, and the value of the longitudinal velocity at the first moment, the value of the roll torque of the vehicle at the first moment can be accurately determined. This can improve the accuracy of determining the value of the target state parameter of the vehicle at the first moment according to the value of the first state parameter at the first moment by using the target method when the above-mentioned target method includes a dynamic method, thereby improving the accuracy of determining the target sideslip angle value and lateral force value of the wheel at the first moment based on the value of the target state parameter at the first moment.

[0155] Optionally, when the target motion condition is a high-speed motion condition, the target method is a dynamic method; the target method is used to determine the initial value of the target state parameter of the vehicle at the first moment according to the value of the first state parameter at the first moment, and may include:

[0156] Using the dynamic equilibrium equation corresponding to the first state parameter, according to the value of the first state parameter at the first moment, the value of the second state parameter of the vehicle at the first moment is determined; the second state parameter includes yaw angular acceleration, roll angular acceleration and lateral acceleration;

[0157] An initial value of the target state parameter at the first moment is determined according to the value of the target state parameter at the second moment and the value of the second state parameter at the first moment.

[0158] Optionally, the dynamic balance equation corresponding to the first state parameter includes a vehicle torque dynamic balance equation and a vehicle lateral force dynamic balance equation. The vehicle torque dynamic balance equation may include a vehicle yaw torque dynamic balance equation and a vehicle roll torque dynamic balance equation.

[0159] Optionally, the vehicle yaw torque dynamic balance equation is formula (25):

[0160]

[0161] Optionally, the vehicle roll torque dynamic balance equation is formula (26):

[0162]

[0163] Optionally, the vehicle lateral force dynamics equilibrium equation is formula (27):

[0164] F y =m*a y (27)

[0165] Among them, α z is the value of the vehicle's yaw angular acceleration at the first moment, α x is the value of the vehicle's roll angular acceleration at the first moment, a y is the value of the vehicle's lateral acceleration at the first moment, I zz is the moment of inertia of the vehicle around the Z axis of the body coordinate system, I xz is the inertia product of the vehicle corresponding to the XZ axis of the body coordinate system, I x is the moment of inertia of the vehicle around the X-axis of the vehicle body coordinate system. Optionally, the contact plane between the wheel and the ground is perpendicular to the Z-axis of the vehicle body coordinate system.

[0166] In the embodiment of the present application, when the target motion condition is a high-speed motion condition, the dynamic equilibrium equation corresponding to the first state parameter can accurately determine the value of the second state parameter of the vehicle at the first moment according to the value of the first state parameter at the first moment, so that the initial value of the target state parameter of the vehicle at the first moment can be accurately determined according to the value of the target state parameter at the second moment and the value of the second state parameter at the first moment, thereby improving the accuracy of determining the target value of the target state parameter of the vehicle at the first moment when the target motion condition is a high-speed motion condition, thereby improving the accuracy of determining the target slip angle value and lateral force value of the wheel at the first moment based on the target value of the target state parameter at the first moment.

[0167] Optionally, the torque of the vehicle mentioned above includes the yaw torque of the vehicle and the roll torque of the vehicle.

[0168] In one embodiment, the above-mentioned use of the dynamic equilibrium equation corresponding to the first state parameter to determine the value of the second state parameter of the vehicle at the first moment according to the value of the first state parameter at the first moment includes:

[0169] Determine the value of at least one of the yaw angular acceleration and the roll angular acceleration at the first moment according to the values ​​of the yaw torque and the roll torque at the first moment by using the vehicle yaw torque dynamic balance equation and the vehicle roll torque dynamic balance equation;

[0170] The vehicle lateral force dynamics equilibrium equation is used to determine the value of the lateral acceleration at the first moment according to the value of the lateral force at the first moment.

[0171] Specifically, the value α of the vehicle's yaw angular acceleration at the first moment can be determined by using formulas (23) to (26): z and the value of the vehicle's roll angular acceleration at the first moment α x The value a of the lateral acceleration at the first moment can be determined by using formulas (18), (19) or (20), (21) or (22), and (27). y .

[0172] Specifically, (25) to (27) can be written in matrix form to obtain formula (28):

[0173]

[0174] Furthermore, formula (28) can be converted into an inverse matrix to obtain formula (29):

[0175]

[0176] Furthermore, the lateral force of the vehicle at the first moment determined based on formulas (18) to (24) can be expressed as y , the value of the vehicle's yaw torque at the first moment M z and the value M of the vehicle's roll torque at the first moment x Substituting into formula (29), we can obtain the value of the vehicle's yaw angular acceleration at the first moment α z , the value of the vehicle's roll angular acceleration at the first moment α x and the lateral acceleration of the vehicle at the first moment a y .

[0177] The embodiment of the present application utilizes the vehicle yaw torque dynamic balance equation and the vehicle roll torque dynamic balance equation. According to the values ​​of the yaw torque and the roll torque at the first moment, the values ​​of the yaw angular acceleration and the roll angular acceleration at the first moment can be accurately determined. By utilizing the vehicle lateral force dynamic balance equation, according to the value of the lateral force at the first moment, the value of the lateral acceleration at the first moment can be accurately determined. This can improve the accuracy of determining the values ​​of the target state parameters of the vehicle at the first moment when the target motion condition is a high-speed motion condition, thereby improving the accuracy of determining the target sideslip angle value and lateral force value of the wheel at the first moment based on the values ​​of the target state parameters at the first moment.

[0178] Determining the initial value of the target state parameter of the vehicle at the first moment according to the value of the target state parameter at the second moment and the value of the second state parameter at the first moment may include:

[0179] Determine an initial value of the lateral speed of the vehicle at the first moment according to the value of the lateral speed of the vehicle at the second moment, the value of the lateral acceleration of the vehicle at the first moment, and a preset time interval; the preset time interval is equal to the interval between the first moment and the second moment;

[0180] Determining an initial value of the yaw angular velocity of the vehicle at the first moment according to a value of the yaw angular velocity of the vehicle at the second moment, a value of the lateral acceleration of the vehicle at the first moment, and a preset time interval;

[0181] Determining an initial value of the roll angular velocity of the vehicle at the first moment according to the value of the roll angular velocity of the vehicle at the second moment, the value of the lateral acceleration of the vehicle at the first moment, and a preset time interval;

[0182] An initial value of the roll angle of the vehicle at the first moment is determined according to the value of the roll angle of the vehicle at the second moment, the value of the roll angular velocity of the vehicle at the first moment, and a preset time interval.

[0183] Optionally, when the second moment is the initial moment when the vehicle is powered on, the values ​​of the lateral velocity, yaw angular velocity, roll angular velocity and roll angle of the vehicle at the second moment are 0.

[0184] Specifically, when the target motion condition is a high-speed motion condition, formulas (30) to (32) can be used to determine the initial value of the vehicle's yaw angular velocity at the first moment, the initial value of the vehicle's roll angular velocity at the first moment, and the initial value of the vehicle's lateral velocity at the first moment:

[0185] V y =∫a y dt=a y *Ts+V y ' (30)

[0186] W z =∫a z dt=a z *Ts+W z ' (31)

[0187] W x =∫a x dt=a x *Ts+W x ' (32)

[0188] Among them, W z is the initial value of the vehicle's yaw rate at the first moment, W x is the initial value of the vehicle's roll angular velocity at the first moment, V y is the initial value of the vehicle's lateral velocity at the first moment, V y' is the value of the lateral speed of the vehicle at the second moment, and Ts is the preset time interval.

[0189] Furthermore, formula (33) can be used to determine the initial value of the vehicle's roll angle at the first moment:

[0190] θ x =∫W x dt=W x *Ts+θ x ' (33)

[0191] Among them, θ x is the initial value of the vehicle's roll angle at the first moment.

[0192] Specifically, formulas (30), (31), and (33) can be written in matrix form to obtain formula (34):

[0193]

[0194] Among them, Y dyn It represents a matrix composed of the initial values ​​of the target state parameters of the vehicle at the first moment when the target motion condition is a high-speed motion condition.

[0195] Furthermore, when the target motion condition is a high-speed motion condition, the yaw angular acceleration of the vehicle at the first moment α determined based on formulas (18) to (24) and (29) can be z , the value of the vehicle's roll angular acceleration at the first moment α x and the lateral acceleration of the vehicle at the first moment a y Substituting into formula (32) and (34) accordingly, we can obtain the initial value matrix Y of the target state parameters of the vehicle at the first moment when the target motion condition is a high-speed motion condition: dyn .

[0196] The embodiment of the present application adopts an integral method, which can accurately determine the initial value of the target state parameter of the vehicle at the first moment according to the value of the target state parameter at the second moment and the value of the second state parameter at the first moment, thereby improving the accuracy of determining the target value of the target state parameter of the vehicle at the first moment when the target motion condition is a high-speed motion condition, thereby improving the accuracy of determining the target sideslip angle value and lateral force value of the wheel at the first moment based on the target value of the target state parameter at the first moment.

[0197] Optionally, when the target motion condition is a low-speed motion condition, the target method is a kinematic method; the adopting target method; and determining the initial value of the target state parameter of the vehicle at the first moment according to the value of the first state parameter at the first moment may include:

[0198] The Ackerman kinematic model is used to determine the initial values ​​of the yaw rate and the lateral velocity at the first moment according to the value of the first state parameter of the vehicle at the first moment.

[0199] Specifically, when the target motion condition is a low-speed motion condition, the initial value of the vehicle's yaw rate at the first moment and the value of the vehicle's lateral velocity at the first moment can be determined by formulas (35) and (36) respectively:

[0200]

[0201] Among them, W z is the initial value of the vehicle’s yaw rate at the first moment, V y is the initial value of the vehicle's lateral velocity at the first moment, V x is the longitudinal velocity of the vehicle at the first moment, θ f is the value of the vehicle's front wheel angle at the first moment, V y ' is the lateral speed of the vehicle at the second moment, L f , L r are the distances from the center of mass of the vehicle to the front and rear axles, respectively.

[0202] In addition, when the target motion condition is a low-speed motion condition, the initial value of the vehicle's roll angle at the first moment is relatively small, and the initial value θ of the vehicle's roll angle at the first moment can be set to x The value is assigned to 0. It is worth mentioning that, when the above target motion condition is a low-speed motion condition, the value of the vehicle's roll angle at the first moment is not limited thereto, as long as it conforms to the kinematic characteristics of the vehicle.

[0203] Furthermore, formulas (35) and (36) can be written in matrix form to obtain formula (37):

[0204]

[0205] Among them, Y kin It represents a matrix composed of the initial values ​​of the target state parameters of the vehicle at the first moment when the target motion condition is a low-speed motion condition.

[0206] Furthermore, V x ,θ f 、V y ',L f and L r Substituting into formula (37), we can obtain the initial value matrix Y of the target state parameters of the vehicle at the first moment when the target motion condition is a low-speed motion condition: kin .

[0207] In the embodiment of the present application, when the target motion condition is a low-speed motion condition, the Ackerman kinematic model is used to accurately determine the initial values ​​of the yaw angular velocity and the lateral velocity at the first moment according to the value of the first state parameter of the vehicle at the first moment, thereby improving the accuracy of determining the target values ​​of the target state parameters of the vehicle at the first moment when the target motion condition is a low-speed motion condition, thereby improving the accuracy of determining the target sideslip angle value and lateral force value of the wheel at the first moment based on the target values ​​of the target state parameters at the first moment.

[0208] Optionally, when the target motion condition is a medium-speed motion condition, the target method is a kinematic method and a dynamic method; the target method is used to determine the initial value of the target state parameter of the vehicle at the first moment according to the value of the first state parameter at the first moment, and may include:

[0209] Step S301: Based on a kinematic method, according to the value of a first target parameter in a first state parameter of the vehicle at the first moment, determining a first value of the target state parameter at the first moment; the first target parameter includes the longitudinal speed and the front wheel steering angle of the vehicle;

[0210] Step S302: determining a second value of the target state parameter at the first moment based on a dynamic method according to a value of a second target parameter in the first state parameter of the vehicle at the first moment; the second target parameter includes at least one of the torque and lateral force of the vehicle;

[0211] Step S303: According to a preset fusion weight, a first value of the target state parameter at the first moment and a second value of the target state parameter at the first moment are fused to obtain an initial value of the target state parameter at the first moment.

[0212] Optionally, the preset fusion weight is determined based on the first preset speed value and the second preset speed value.

[0213] The specific implementation process of step S301 and step S302 may refer to the above embodiment and will not be described again here.

[0214] For step S303, the initial value of the target state parameter at the first moment can be determined by formulas (38) and (39):

[0215] Y=Y kin +A*(Y dyn -Y kin ) (38)

[0216]

[0217] Among them, Y is a matrix composed of the initial value of the vehicle's yaw angular velocity at the first moment, the initial value of the vehicle's lateral velocity at the first moment, and the initial value of the vehicle's roll angle at the first moment, which are determined when the target motion condition is a medium-speed motion condition; A is the preset fusion weight; B is the first preset speed value; C is the second preset speed value.

[0218] In the embodiment of the present application, when the target motion condition is a medium-speed motion condition, the first value of the target state parameter at the first moment determined based on the kinematic method and the second value of the target state parameter at the first moment determined based on the dynamic method are fused according to a preset fusion weight, so that the initial value of the target state parameter at the first moment can be accurately determined, thereby improving the accuracy of determining the target value of the target state parameter of the vehicle at the first moment when the target motion condition is a medium-speed motion condition, thereby improving the accuracy of determining the target sideslip angle value and lateral force value of the wheel at the first moment based on the target value of the target state parameter at the first moment.

[0219] In one embodiment, determining the target value of the target state parameter at the first moment according to the initial value of the target state parameter at the first moment includes:

[0220] Obtaining the limit value of the target state parameter at the first moment;

[0221] According to the relationship between the initial value of the target state parameter at the first moment and the limited value of the target state parameter at the first moment, the initial value of the target parameter at the first moment or the limited value of the target state parameter at the first moment is determined as the target value of the target state parameter at the first moment.

[0222] Optionally, the limit value of the target state parameter at the first moment includes a first limit value of the target state parameter at the first moment and a second limit value of the target state parameter at the first moment, and the first limit value of the target state parameter at the first moment is less than the second limit value of the target state parameter at the first moment.

[0223] Determining the initial value of the target parameter at the first moment or the limited value of the target state parameter at the first moment as the target value of the target state parameter at the first moment according to the relationship between the initial value of the target state parameter at the first moment and the limited value of the target state parameter at the first moment may include:

[0224] In the case where the initial value of the target state parameter at the first moment is within the second target interval, the initial value of the target state parameter at the first moment is determined as the target value of the target state parameter at the first moment; the second target interval is a closed interval consisting of the first limiting value of the target state parameter at the first moment and the second limiting value of the target state parameter at the first moment;

[0225] In a case where the initial value of the target state parameter at the first moment is greater than the second limiting value of the target state parameter at the first moment, determining the second limiting value of the target state parameter at the first moment as the target value of the target state parameter at the first moment;

[0226] When the initial value of the target state parameter at the first moment is less than the first limit value of the target state parameter at the first moment, the first limit value of the target state parameter at the first moment is determined as the target value of the target state parameter at the first moment.

[0227] The embodiment of the present application determines the initial value of the target state parameter at the first moment or the limited value of the target state parameter at the first moment as the target value of the target state parameter at the first moment based on the relationship between the initial value of the target state parameter at the first moment and the limited value of the target state parameter at the first moment, which can ensure the rationality of the target value of the target state parameter at the first moment, and further improve the reliability of determining the target sideslip angle value and lateral force value of the wheel at the first moment based on the target value of the target state parameter at the first moment, thereby improving the driving safety of the vehicle.

[0228] In one embodiment, the step of obtaining a limit value of a target state parameter at a first moment includes:

[0229] In the case where the target state parameter includes the lateral speed, determining a limit value of the lateral speed at the first moment according to a maximum allowable slip angle value of the vehicle and a value of the longitudinal speed of the vehicle at the first moment;

[0230] In the case where the target state parameter includes the yaw angular velocity, determining a limit value of the yaw angular velocity at the first moment according to a collected value of the yaw angular velocity at the first moment and a third difference; the third difference is a difference between a maximum allowable yaw angular velocity value of the vehicle and a collected value of the yaw angular velocity at the first moment;

[0231] In the case where the target state parameter includes the roll angle, a limit value of the roll angle at the first moment is determined according to a maximum allowable roll angle value of the vehicle.

[0232] Specifically, when the limit value of the target state parameter at the first moment includes the first limit value and the second limit value, the limit value of the lateral speed of the vehicle at the first moment can be determined by formulas (40) and (41), respectively:

[0233]

[0234] in, are the first limit value and the second limit value of the lateral speed of the vehicle at the first moment respectively; V x is the value of the vehicle's longitudinal velocity at the first moment; α maxThe maximum allowable slip angle of the vehicle.

[0235] The limit value of the vehicle's yaw rate at the first moment can be determined by formulas (42) and (43) respectively:

[0236]

[0237] in, are respectively the first limit value and the second limit value of the yaw angular velocity of the vehicle at the first moment; W z_snsr is the collected value of the vehicle's yaw rate at the first moment; W z_Lim is the difference between the maximum allowable yaw rate value of the vehicle and the collected value of the yaw rate at the first moment, that is, the third difference.

[0238] The limit value of the vehicle's roll angle at the first moment can be determined by formulas (44) and (45) respectively:

[0239]

[0240] in, are the first limit value and the second limit value of the roll angle of the vehicle at the first moment respectively; θ x_max The maximum allowable roll angle of the vehicle.

[0241] The embodiment of the present application can accurately determine the limit value of the lateral velocity at the first moment based on the maximum allowable slip angle value of the vehicle and the value of the longitudinal velocity of the vehicle at the first moment; can accurately determine the limit value of the yaw velocity at the first moment based on the collected value of the yaw angular velocity at the first moment and the difference between the maximum allowable yaw angular velocity value of the vehicle and the collected value of the yaw angular velocity at the first moment; can determine the limit value of the roll angle at the first moment based on the maximum allowable roll angle value of the vehicle, and further can ensure the rationality of determining the target value of the target state parameter at the first moment based on the relationship between the initial value and the limit value of the target state parameter at the first moment, thereby improving the reliability of determining the wheel slip angle and the wheel lateral force based on the target value of the target state parameter at the first moment, and can improve the driving safety of the vehicle.

[0242] See also Figure 4 The embodiment of the present application also provides a wheel state determination device 400, which can implement the above-mentioned wheel state determination method. The device includes: an acquisition module 401, a first determination module 402 and a second determination module 403.

[0243] The acquisition module 401 is used to acquire the initial slip angle value of the wheel at the first moment;

[0244] The first determination module 402 is used to determine the slip angle change rate of the wheel at a first moment according to the ratio of the first difference to the elastic hysteresis time of the wheel; the first difference is the difference between the initial slip angle value and the slip angle value of the wheel at a second moment; the second moment is earlier than the first moment;

[0245] The second determination module 403 is used to determine a target slip angle value of the wheel at the first moment according to the slip angle value and the slip angle change rate of the wheel at the second moment.

[0246] The wheel state determination device provided in the embodiment of the present application can implement the various steps of the above-mentioned wheel state determination method embodiment and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0247] See also Figure 5 The embodiment of the present application also provides an electronic device 500, including a processor 501 and a memory 502, the memory 502 stores a program or instruction that can be run on the processor 501, and the program or instruction is executed by the processor 501 to implement the various steps of the above-mentioned wheel state determination method embodiment, and can achieve the same technical effect, to avoid repetition, it is not repeated here. It should be noted that the electronic device in the embodiment of the present application includes a mobile electronic device and a non-mobile electronic device.

[0248] Figure 6 A schematic diagram of the hardware structure of an electronic device for implementing an embodiment of the present application is provided, wherein the electronic device includes:

[0249] The processor 601 may be implemented by a general-purpose central processing unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of the present application;

[0250] The memory 602 can be implemented in the form of a read-only memory (ROM), a static storage device, a dynamic storage device or a random access memory (RAM). The memory 602 can store an operating system and other application programs. When the technical solution provided in the embodiment of this specification is implemented by software or firmware, the relevant program code is stored in the memory 602, and the processor 601 calls and executes the wheel state determination method of the embodiment of this application;

[0251] Input / output interface 603, used to implement information input and output;

[0252] Communication interface 604, used to realize communication interaction between the device and other devices, which can be realized by wired mode (such as USB, network cable, etc.) or wireless mode (such as mobile network, WIFI, Bluetooth, etc.);

[0253] Bus 605 , which transmits information between various components of the device (e.g., processor 601 , memory 602 , input / output interface 603 , and communication interface 604 );

[0254] The processor 601 , the memory 602 , the input / output interface 603 and the communication interface 604 are connected to each other in communication within the device via a bus 605 .

[0255] The electronic device provided in the embodiment of the present application can implement each step of the above-mentioned wheel state determination method embodiment and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0256] An embodiment of the present application also provides a computer-readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, the various steps of the above-mentioned wheel state determination method embodiment are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0257] The processor is the processor in the electronic device described in the above embodiment. The computer-readable storage medium includes a computer-readable storage medium such as a computer read-only memory ROM, a random access memory RAM, a magnetic disk or an optical disk.

[0258] The embodiment of the present application also provides a vehicle, comprising the electronic device described in the above embodiment. The vehicle can implement the various steps of the above wheel state determination method embodiment through the above electronic device, and can achieve the same technical effect, so to avoid repetition, it will not be repeated here.

[0259] The wheel state determination method, device, electronic device, storage medium and vehicle provided by the present application consider the influence of the lateral force generated by the vehicle roll state on the wheel slip angle, and can accurately determine the initial slip angle value of the wheel at the first moment based on the product of the steering roll coefficient corresponding to the wheel and the target value of the vehicle's roll angle at the first moment. Further, the influence of the elastic hysteresis effect of the wheel on the wheel slip angle is also considered. Based on the initial slip angle value of the wheel at the first moment and the elastic hysteresis time, the slip angle change rate of the wheel at the first moment can be accurately determined. Further, by using the integral method, based on the slip angle change rate of the wheel at the first moment, the target slip angle value of the wheel at the first moment can be accurately determined, thereby improving the accuracy of determining the wheel slip angle and the wheel lateral force. In addition, the wheel state determination method, device, electronic device, storage medium and vehicle provided by the present application have low requirements for the instantaneous quality of the signal of the vehicle sensor, can reduce the filtering module, and can improve the real-time performance of the vehicle input signal.

[0260] An embodiment of the present application further provides a chip, which includes a processor and a communication interface, the communication interface and the processor are coupled, and the processor is used to run programs or instructions to implement the various steps of the above-mentioned wheel state determination method embodiment, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0261] It should be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

[0262] An embodiment of the present application provides a computer program product, which is stored in a storage medium. The program product is executed by at least one processor to implement the various steps of the above-mentioned wheel state determination method embodiment, and can achieve the same technical effect. To avoid repetition, it will not be repeated here.

[0263] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not delete the existence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0264] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a computer software product, which is stored in a storage medium (such as ROM / RAM, a disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0265] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A method for determining a wheel state, characterized in that: include: Get the initial slip angle value of the wheel at the first moment; determining a slip angle change rate of the wheel at the first moment according to a ratio of the first difference to the elastic hysteresis time of the wheel; the first difference is a difference between the initial slip angle value and the slip angle value of the wheel at the second moment; the second moment is earlier than the first moment; A target slip angle value of the wheel at the first moment is determined according to the slip angle value of the wheel at the second moment and the slip angle change rate.

2. The wheel state determination method according to claim 1, characterized in that: Before determining the sideslip angle change rate of the wheel at the first moment according to the ratio of the first difference to the elastic hysteresis time of the wheel, the wheel state determination method further includes: Obtaining the lateral slack length of the wheel; The elastic hysteresis time is determined as a function of the ratio of the lateral relaxation length to the value of the longitudinal velocity of the vehicle at the first instant.

3. The wheel state determination method according to claim 1, characterized in that: The obtaining of the initial slip angle value of the wheel at the first moment comprises: Determining a first angle value between the pointing direction of the wheel at the first moment and the longitudinal direction of the vehicle at the first moment according to the product of the steering roll coefficient corresponding to the wheel and the target value of the roll angle of the vehicle at the first moment; Determine, by using a kinematic formula, a second angle value between a center of mass velocity direction of the wheel at the first moment and a longitudinal direction of the vehicle at the first moment according to a value of the longitudinal velocity of the vehicle at the first moment and target values ​​of the lateral velocity and yaw angular velocity of the vehicle at the first moment; A second difference between the first angle value and the second angle value is determined as the initial slip angle value.

4. The wheel state determination method according to claim 3, characterized in that: The wheel state determination method further comprises: Acquire a target motion condition of the vehicle at the first moment; Obtaining a target method and a value of a first state parameter corresponding to the target motion condition at the first moment; wherein the target method includes at least one of a kinematic method and a dynamic method; when the target method includes the kinematic method, the first state parameter includes a longitudinal speed and a front wheel angle of the vehicle; when the target method includes the dynamic method, the first state parameter includes a torque and a lateral force of the vehicle; Adopting the target method, determining the initial value of the target state parameter of the vehicle at the first moment according to the value of the first state parameter at the first moment; wherein the target state parameter includes yaw rate, roll angle and lateral speed; According to the initial value of the target state parameter at the first moment, a target value of the target state parameter at the first moment is determined.

5. The wheel state determination method according to claim 4, characterized in that: In the case where the target motion condition is a high-speed motion condition, the target method is the dynamic method; The adopting the target method to determine the initial value of the target state parameter of the vehicle at the first moment according to the value of the first state parameter at the first moment includes: Determining the value of a second state parameter of the vehicle at the first moment by using the dynamic equilibrium equation corresponding to the first state parameter and according to the value of the first state parameter at the first moment; the second state parameter includes yaw angular acceleration, roll angular acceleration and lateral acceleration; An initial value of the target state parameter at the first moment is determined according to the value of the target state parameter at the second moment and the value of the second state parameter at the first moment.

6. The wheel state determination method according to claim 1, characterized in that: After determining the target slip angle value of the wheel at the first moment, the wheel state determination method further includes: Obtaining a brush tire model corresponding to the target slip angle value; The brush tire model is used to determine the lateral force value of the wheel at the first moment according to the target slip angle value.

7. A wheel state determination device, characterized in that: It includes an acquisition module, a first determination module and a second determination module; The acquisition module is used to acquire the initial slip angle value of the wheel at the first moment; The first determination module is used to determine the slip angle change rate of the wheel at the first moment according to the ratio of the first difference to the elastic hysteresis time of the wheel; the first difference is the difference between the initial slip angle value and the slip angle value of the wheel at the second moment; the second moment is earlier than the first moment; The second determination module is used to determine a target slip angle value of the wheel at the first moment according to the slip angle value of the wheel at the second moment and the slip angle change rate.

8. An electronic device, characterized in that: The electronic device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the wheel state determination method according to any one of claims 1 to 6 when executing the computer program.

9. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the wheel state determination method according to any one of claims 1 to 6 is implemented.

10. A vehicle, characterized in that: The vehicle comprises the electronic device as claimed in claim 8.

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