Vehicle and control method and apparatus therefor, storage medium, and computer program product

Abstract

A vehicle and a control method and apparatus therefor, a storage medium, and a computer program product, relating to the technical field of vehicles. The control method for a vehicle comprises: correcting an ideal yaw rate on the basis of desired steering characteristic information; obtaining an additional yaw moment on the basis of an ideal sideslip angle, the corrected ideal yaw rate, and an actual sideslip angle and an actual yaw rate of a vehicle; and performing torque distribution on the basis of the additional yaw moment. In the method, the ideal yaw rate is corrected on the basis of the desired steering characteristic information, so that, on the basis of the ideal sideslip angle, the corrected ideal yaw rate, and the actual sideslip angle and the actual yaw rate of the vehicle, variable steering characteristics of the vehicle are achieved by means of torque control, thereby enabling the vehicle to obtain higher steering sensitivity.

Description

Vehicle, control method, device, storage medium and computer program product

[0001] Cross-reference to related applications

[0002] The present application claims priority to the Chinese patent application No. 202410866251.1, filed on June 28, 2024, and entitled "Vehicle, control method, device, storage medium and computer program product", the entire content of which is incorporated herein by reference. TECHNICAL FIELD

[0003] The present application relates to the technical field of vehicles, and in particular to a vehicle, a control method, a device, a storage medium and a computer program product. BACKGROUND

[0004] In the related art, the track mode is mainly aimed at improving the power performance of the vehicle. For example, when it is detected that the track mode is turned on, the driving motor is controlled to output the maximum torque, and the battery management system is controlled to output the maximum power. Although this technology can maximize the power performance of the vehicle, it lacks control over the steering characteristics of the vehicle and has certain limitations, which restricts the driving skills of skilled drivers and lacks driving pleasure. SUMMARY

[0005] The present application aims to at least partially solve one of the technical problems in the related art. To this end, the present application aims to provide a vehicle, a control method, a device, a storage medium and a computer program product, so that the vehicle can have higher steering sensitivity.

[0006] In a first aspect, the present application provides a control method of a vehicle, comprising: correcting a desired yaw rate according to desired steering characteristic information; obtaining an additional yaw moment based on a desired center of mass side slip angle, the corrected desired yaw rate, and an actual center of mass side slip angle and an actual yaw rate of the vehicle; and performing torque distribution based on the additional yaw moment.

[0007] In some embodiments of the present application, the correcting the desired yaw rate according to the desired steering characteristic information comprises: obtaining a variable steering characteristic coefficient according to the desired steering characteristic information; and correcting the desired yaw rate according to the variable steering characteristic coefficient.

[0008] In some embodiments of the present application, the desired steering characteristic information comprises a desired steering characteristic value θ, and the obtaining the variable steering characteristic coefficient according to the desired steering characteristic information comprises:

[0009] When θ is greater than 0, the variable steering characteristic coefficient is obtained as θ*K;

[0010] When θ is equal to 0, the variable steering characteristic coefficient is 0;

[0011] When θ is less than 0, the variable steering characteristic coefficient is

[0012] Wherein, K is a stability factor, τ is a preset safety factor, u cr is a critical vehicle speed when the vehicle is in a spin condition in an over-steering state.

[0013] In some embodiments of the present application, before the ideal yaw rate is corrected according to the variable steering characteristic coefficient, the method further comprises limiting the variable steering characteristic coefficient by:

[0014] comparing the variable steering characteristic coefficient with and K respectively;

[0015] if the variable steering characteristic coefficient is less than , the variable steering characteristic coefficient is limited to

[0016] if the variable steering characteristic coefficient is greater than K, the variable steering characteristic coefficient is limited to K;

[0017] if the variable steering characteristic coefficient is greater than or equal to and less than or equal to K, the variable steering characteristic coefficient is kept unchanged.

[0018] In some embodiments of the present application, the correction of the ideal yaw rate according to the variable steering characteristic coefficient comprises: replacing the stability factor used to calculate the ideal yaw rate with the variable steering characteristic coefficient to achieve the correction of the ideal yaw rate.

[0019] In some embodiments of the present application, the additional yaw moment is obtained according to the ideal center of mass side slip angle, the corrected ideal yaw rate, and the actual center of mass side slip angle and the actual yaw rate of the vehicle, comprising: limiting the ideal center of mass side slip angle and the corrected ideal yaw rate by using the road adhesion coefficient of the road on which the vehicle is located to obtain a reference center of mass side slip angle and a reference yaw rate; obtaining the additional yaw moment according to the reference center of mass side slip angle, the reference yaw rate, and the actual center of mass side slip angle and the actual yaw rate.

[0020] In some embodiments of the present application, the limiting the ideal yaw rate by using the road adhesion coefficient to obtain the reference yaw rate comprises: determining a maximum yaw rate according to the road adhesion coefficient; comparing the ideal yaw rate with the maximum yaw rate; if the ideal yaw rate is greater than the maximum yaw rate, taking the maximum yaw rate as the reference yaw rate; and if the ideal yaw rate is less than or equal to the maximum yaw rate, taking the ideal yaw rate as the reference yaw rate.

[0021] In some embodiments of the present application, the correcting the ideal vehicle body side slip angle by using the road adhesion coefficient respectively to obtain the reference vehicle body side slip angle comprises: determining a maximum vehicle body side slip angle according to the road adhesion coefficient; comparing the ideal vehicle body side slip angle with the maximum vehicle body side slip angle; if the ideal vehicle body side slip angle is greater than the maximum vehicle body side slip angle, taking the maximum vehicle body side slip angle as the reference vehicle body side slip angle; and if the ideal vehicle body side slip angle is less than or equal to the maximum vehicle body side slip angle, taking the ideal vehicle body side slip angle as the reference vehicle body side slip angle.

[0022] In some embodiments of the present application, the maximum yaw rate is wherein μ is the road adhesion coefficient, g is the gravity acceleration, u is the vehicle speed of the vehicle, and η is a preset safety coefficient.

[0023] In some embodiments of the present application, the maximum vehicle body side slip angle is tan -1 0.02 μg, wherein μ is the road adhesion coefficient and g is the gravity acceleration.

[0024] In some embodiments of the present application, the obtaining the additional yaw moment according to the reference vehicle body side slip angle, the reference yaw rate, the actual vehicle body side slip angle and the actual yaw rate comprises: calculating a first difference value between the reference yaw rate and the actual yaw rate, and calculating a second difference value between the reference vehicle body side slip angle and the actual vehicle body side slip angle; and obtaining the additional yaw moment according to the first difference value and the second difference value by using a preset closed-loop control algorithm.

[0025] In some embodiments of the present application, the vehicle is a distributed drive vehicle; and the distributing torque based on the additional yaw moment comprises:

[0026] The torque is distributed by the following formula:

[0027] In the formula, T reqL and T reqRrespectively, are the distribution torques of the left and right drive motors of the vehicle, T reqAXLE is the total drive torque of the drive shaft, R w is the rolling radius of the wheel, B is the wheel base of the drive shaft, i L and i R respectively, are the reduction ratios of the left and right drive motors, M z,req is the additional yaw moment.

[0028] In a second aspect, an embodiment of the present application provides a control device of a vehicle, comprising: a correction module configured to correct an ideal yaw rate according to expected steering characteristic information; a processing module configured to obtain an additional yaw moment according to an ideal center side slip angle, the corrected ideal yaw rate, an actual center side slip angle and an actual yaw rate of the vehicle; and a distribution module configured to distribute torque based on the additional yaw moment.

[0029] In a third aspect, an embodiment of the present application provides a vehicle, comprising the control device of the vehicle according to the second aspect.

[0030] In a third aspect, an embodiment of the present application provides a computer readable storage medium, having stored thereon a computer program, which, when executed by a processor, implements the method according to the first aspect.

[0031] In a fourth aspect, an embodiment of the present application provides a computer program product, comprising a computer program, which, when executed by a processor, implements the method according to the first aspect.

[0032] The vehicle and the control method, device, storage medium and computer program product of the embodiments of the present application correct the ideal yaw rate according to the expected steering characteristic information, and then realize the variable steering characteristic of the vehicle through torque control based on the ideal center side slip angle, the corrected ideal yaw rate, the actual center side slip angle and the actual yaw rate of the vehicle, so that the vehicle can obtain higher steering sensitivity. BRIEF DESCRIPTION OF DRAWINGS

[0033] FIG. 1 is a curve of steady-state yaw rate gain and vehicle speed according to an embodiment;

[0034] FIG. 2 is a flowchart of a control method of a vehicle according to an embodiment of the present application;

[0035] FIG. 3 is a flowchart of step S21 according to an embodiment of the present application;

[0036] FIG. 4 is a flowchart of step S22 according to an embodiment of the present application;

[0037] Fig. 5 is a flowchart of a control method of a vehicle according to an embodiment of the present application;

[0038] Fig. 6 is a flowchart of step S53 according to an embodiment of the present application;

[0039] Fig. 7 is a block diagram of a control device of a vehicle according to an embodiment of the present application;

[0040] Fig. 8 is a block diagram of a vehicle according to an embodiment of the present application. DETAILED DESCRIPTION

[0041] Embodiments of the present application will be described in detail below with reference to the drawings, in which like or similar components that have the same or similar functions are denoted by like reference numerals throughout the several drawings. Embodiments described below are exemplary and are intended to serve only for the purpose of explaining the present application and should not be understood as limiting the present application.

[0042] The basis of vehicle torque distribution is vehicle handling stability control, and the vehicle handling stability control first determines a proper ideal reference model, which represents the driving intention of the driver and the ideal response characteristics of the vehicle. Common vehicle models include two-degree-of-freedom, three-degree-of-freedom, seven-degree-of-freedom, etc. models. The linear two-degree-of-freedom model is mainly directed to the handling stability response characteristics of the vehicle in the linear range, which is a predictable and familiar response characteristic of the vehicle for the driver, and thus the linear two-degree-of-freedom model can represent the handling intention of the driver to a large extent.

[0043] According to the linear two-degree-of-freedom model, the ideal vehicle yaw rate is as follows:

[0044] where u is the vehicle speed, L is the wheelbase of the vehicle, and δ is the Ackerman angle of the front wheels (referring to the included angle between the two front wheels when the vehicle is turning, which is related to the steering wheel angle of the vehicle). K is the stability factor, which is an important parameter representing the steering characteristics of the vehicle, and is only related to the mass of the vehicle, the longitudinal position of the mass center, and the tire cornering stiffness, and is an inherent attribute of the vehicle structure.

[0045] The calculation formula of the stability factor K is as follows:

[0046] where m is the mass of the vehicle, a is the distance from the mass center of the vehicle to the front axle, b is the distance from the mass center of the vehicle to the rear axle, and k1 is the cornering stiffness of the front wheels (negative value) and k2 is the cornering stiffness of the rear wheels (negative value). It should be noted that the above calculation formula of K is derived from the linear two-degree-of-freedom model, and the linear two-degree-of-freedom model simplifies the vehicle to the maximum extent, only considering the yaw and lateral motion caused by the lateral force of the wheels, and omitting many factors such as camber, toe-in, and load variation of the wheels.

[0047] The stability factor K is an important parameter for characterizing the steering characteristics of a vehicle, and according to the sign of the stability factor K, the steering characteristics can be divided into three categories (as shown in FIG. 1):

[0048] When K = 0, the vehicle is in a neutral steering state, as shown in FIG. 1, in which the steady-state yaw rate is linearly related to the vehicle speed;

[0049] When K > 0, the vehicle is in an understeering state, as shown in FIG. 1, in which the curve of the vehicle speed and the steady-state yaw rate gain is curved downward, and the steady-state yaw rate gain reaches a maximum value at a characteristic vehicle speed u c□ .

[0050] When K < 0, the vehicle is in an oversteering state, as shown in FIG. 1, in which the curve of the vehicle speed and the steady-state yaw rate gain is curved upward, and the steady-state yaw rate gain becomes infinite at a critical vehicle speed u cr , and at this time, a small angle of the front wheels can cause the vehicle to rotate violently (spin), which is very dangerous and can easily cause the vehicle to slide or even overturn.

[0051] Ideally, a vehicle should have a completely linear response characteristic, i.e., be in a neutral steering state, to meet the steering intention of the driver. However, in actual situations, in order to prevent the vehicle from spinning severely when the vehicle is in an oversteering state, the vehicle is generally designed to have a slight understeering characteristic.

[0052] As can be seen from the above analysis, the stability design of a vehicle is at the expense of the steering performance. Therefore, in the design of racing vehicles that focus on vehicle performance, the vehicle is often designed to have a slight oversteering characteristic to meet the requirements of the driver for high steering sensitivity and improve the steering performance of the vehicle.

[0053] With more and more attention being paid to individualization and driving pleasure of vehicles, and the racing mode in the related art mainly aiming to improve the power performance of the vehicle, the present application provides a control method for a vehicle, which corrects the ideal yaw rate according to expected steering characteristic information, and then realizes variable steering characteristics of the vehicle through torque control, so that the vehicle can obtain higher steering sensitivity, i.e., tends to have an oversteering characteristic, which is helpful for skilled drivers to realize fast cornering and for non-skilled drivers to easily experience the driving pleasure of "spinning" and "pushing the head". Meanwhile, based on the control method for the vehicle, a control device for the vehicle, a vehicle, and a storage medium and a computer program product are provided.

[0054] The vehicle and the control method, device, storage medium, and computer program product thereof according to the embodiments of the present application are described below with reference to the accompanying drawings.

[0055] Fig. 2 is a flow chart of a control method of a vehicle according to an embodiment of the present application. The control method can be executed by an electronic device, which can be a vehicle controller or a device independent of the vehicle controller and used to implement vehicle dynamics control.

[0056] As shown in Fig. 2, the control method of the vehicle includes:

[0057] S21, correcting the ideal yaw rate according to the expected steering characteristic information.

[0058] The expected steering characteristic information can be a value in a preset range (such as a range of [-100%, 100%], [-1, 1], etc.) and can be defined as an expected steering characteristic value. For ease of description, the expected steering characteristic value can be represented by a symbol θ, i.e., θ ∈ [-100%, 100%], θ ∈ [-1, 1], etc. When the symbol θ is positive, it indicates that the expected driving characteristic is understeering, and the greater the absolute value, the greater the understeering amount. When the symbol θ is negative, it indicates that the expected driving characteristic is oversteering, and the greater the absolute value, the greater the oversteering amount.

[0059] As an implementation, the expected steering characteristic information is set by a driver, such as input through an HMI (Human Machine Interface). For example, a track mode start button can be provided in the vehicle, and the driver can start the track mode of the vehicle by pressing the start button. At this time, the vehicle terminal can display a track mode page through the HMI interface, and the page includes an expected steering characteristic information input control, and the driver can input the expected steering characteristic information in the input control.

[0060] As another implementation, the expected steering characteristic information is a default setting. For example, after the driver starts the track mode, the expected steering characteristic information is not set, and the expected steering characteristic information θ can be set as 100% by default, i.e., the steering characteristic of the vehicle remains unchanged and is still understeering.

[0061] Optionally, before step S21, the control method can further include determining that the vehicle starts the track mode.

[0062] In this embodiment, the ideal yaw rate can be obtained through the above-mentioned degree-of-freedom model. Taking a linear two-degree-of-freedom model as an example, the ideal yaw rate As an implementation, a corresponding relationship between the expected steering characteristic information and K (which can be stored in the form of a table, a curve, a function, etc.) can be established in advance, and the corresponding relationship can be obtained through experiments, and the target of the experiments is to improve the steering flexibility of the vehicle. In actual use, the corresponding K value can be obtained according to the expected steering characteristic information, and then the K value in the ideal yaw rate is replaced by the obtained K value, so as to correct the ideal yaw rate. ​

[0063] It should be noted that the vehicle speed u and the front wheel Ackerman angle δ for calculating the ideal yaw rate can be sensed by corresponding sensors. For example, the vehicle speed u can be sensed directly by a vehicle speed sensor or calculated by wheel speed sensed by a wheel speed sensor; the front wheel Ackerman angle δ can be calculated by the steering wheel angle sensed by a steering wheel sensor.

[0064] S22, obtaining an additional yaw moment based on the ideal centroid side slip angle, the corrected ideal yaw rate, and the actual centroid side slip angle and the actual yaw rate of the vehicle.

[0065] In this embodiment, the ideal centroid side slip angle can also be obtained by the above-mentioned two-degree-of-freedom model. Taking a linear two-degree-of-freedom model as an example, the ideal centroid side slip angle where u is the vehicle speed, L is the wheelbase of the vehicle, δ is the front wheel Ackerman angle, m is the mass of the vehicle, a is the distance from the centroid of the vehicle to the front axle, b is the distance from the centroid of the vehicle to the rear axle, k1 is the front wheel cornering stiffness (negative value), and k2 is the rear wheel cornering stiffness (negative value).

[0066] The actual centroid side slip angle β is the angle between the centroid speed direction of the vehicle and the direction of the vehicle head, which can be obtained by an electronic device or a vehicle controller according to the centroid lateral speed u x and the centroid longitudinal speed u y by the following formula: β = arctan(u y / u x )

[0067] The actual yaw rate can be sensed by a yaw rate sensor arranged on the vehicle and sent to the electronic device.

[0068] As an embodiment, after obtaining the ideal centroid side slip angle, the corrected ideal yaw rate, and the actual centroid side slip angle and the actual yaw rate, the difference between the ideal centroid side slip angle and the actual centroid side slip angle can be calculated, and the difference between the corrected ideal yaw rate and the actual yaw rate can be calculated. The two differences are input into a preset controller (such as a PID controller, a fuzzy controller, a fuzzy PID controller, etc.) as a closed-loop feedback, and an additional yaw moment is output. Among them, the two differences can be input into two preset controllers respectively, and the two preset controllers output respective additional yaw moments, and then the two additional yaw moments are weighted to obtain a final additional yaw moment for subsequent torque distribution; the two differences can also be input into a preset controller, and the preset controller outputs an additional yaw moment for subsequent torque distribution.

[0069] S23, performing torque distribution based on the additional yaw moment.

[0070] In particular, the vehicle can be a distributed drive vehicle, and a torque distribution controller can be utilized to distribute torque based on an additional yaw moment with an optimization objective of minimizing the sum of squares of tire load rates. The tire load rate refers to a ratio between an actual load amount of a tire and a rated load amount. This ratio reflects a relationship between a load condition of the tire in actual use and a maximum load capacity specified when the tire is designed. For example, if the rated load amount of the tire is 1000 kg and the actual load amount is 800 kg, the tire load rate is 80%.

[0071] As an embodiment, the distribution torque of each wheel can be obtained by a dynamic load distribution algorithm through the following equation:

[0072] where T req,fl , T req,fr , T req,rl , and T req,rr are the distribution torques of the left front wheel drive motor, the right front wheel drive motor, the left rear wheel drive motor, and the right rear wheel drive motor, respectively, F fl , F fr , F rl , and F rr are the vertical loads received by the left front wheel, the right front wheel, the left rear wheel, and the right rear wheel, respectively, and can be calculated by vehicle speed, vehicle longitudinal acceleration, etc., d is the wheel track, and M z,req is the additional yaw moment, and R w is the wheel rolling radius.

[0073] As another embodiment, the torque distribution can be performed based on the total drive torque of the drive shaft through the following equation:

[0074] where T reqL and T reqR are the distribution torques of the left side drive motor and the right side drive motor, respectively, T reqAXLE is the total drive torque of the drive shaft (which can be obtained according to the accelerator pedal opening degree of the vehicle), R w is the wheel rolling radius, B is the drive shaft wheel track, i L and i R are the reduction ratios of the left side drive motor and the right side drive motor, respectively, and M z,req is the additional yaw moment.

[0075] The control method of the vehicle corrects the ideal yaw rate according to the expected steering characteristic information, and then realizes the variable steering characteristic of the vehicle through torque control based on the ideal mass side slip angle, the corrected ideal yaw rate, and the actual mass side slip angle and actual yaw rate of the vehicle, so that the vehicle can obtain higher steering sensitivity, i.e. tends to over-steer characteristic, which helps skilled drivers to realize fast cornering, and non-skilled drivers can also easily experience the driving pleasure of "slip tail" and "push head".

[0076] In some embodiments of the present application, as shown in FIG. 3, the correction of the ideal yaw rate according to the expected steering characteristic information includes:

[0077] S211, obtaining a variable steering characteristic coefficient according to the expected steering characteristic information.

[0078] Specifically, a corresponding relationship between the expected steering characteristic information and the variable steering characteristic coefficient can be established in advance (which can be stored in the form of a table, a curve, a function, etc.), and in actual use, the variable steering characteristic coefficient can be obtained by looking up the corresponding relationship according to the expected steering characteristic information.

[0079] In some examples, the expected steering characteristic information includes an expected steering characteristic value θ; obtaining the variable steering characteristic coefficient according to the expected steering characteristic information includes:

[0080] When θ is greater than 0, the variable steering characteristic coefficient is obtained as θ*K;

[0081] When θ is equal to 0, the variable steering characteristic coefficient is obtained as 0;

[0082] When θ is less than 0, the variable steering characteristic coefficient is obtained as

[0083] Wherein, K is a stability factor, τ is a preset safety coefficient, and u cr is the critical vehicle speed when the vehicle is in the over-steering state and the critical turning condition occurs.

[0084] In this example, the corresponding relationship between the expected steering characteristic information θ and the variable steering characteristic coefficient K can be represented by the following function:

[0085] It should be noted that K in the above function is a fixed value and is greater than 0, i.e. the vehicle is designed to have a slight under-steer characteristic as mentioned above, so as to maximize the stability of the vehicle in the non-racing mode.

[0086] S212, correcting the ideal yaw rate according to the variable steering characteristic coefficient.

[0087] ​Specifically, the variable steering characteristic coefficient can replace the stability factor K in the ideal reference model adopted by the torque distribution of the distributed drive vehicle to correct the ideal yaw rate. Taking the ideal yaw rate obtained by the two-degree-of-freedom model as an example, the corrected ideal yaw rate is: wherein φ is the variable steering characteristic coefficient, ω rd is the corrected ideal yaw rate.

[0088] By introducing the variable steering characteristic coefficient, the ideal yaw rate is corrected, which can effectively improve the steering sensitivity of the vehicle and change the steering characteristic.

[0089] In some embodiments of the present application, before the ideal yaw rate is corrected according to the variable steering characteristic coefficient, the method further comprises limiting the variable steering characteristic coefficient by the following manner:

[0090] comparing the variable steering characteristic coefficient with and K respectively;

[0091] if the variable steering characteristic coefficient is less than , the variable steering characteristic coefficient is limited to

[0092] if the variable steering characteristic coefficient is greater than K, the variable steering characteristic coefficient is limited to K;

[0093] if the variable steering characteristic coefficient is greater than or equal to and less than or equal to K, the variable steering characteristic coefficient is kept unchanged.

[0094] Specifically, in the race track mode, the vehicle needs to have basic stability to avoid the dangerous working condition of excessive steering caused by insufficient steering of the vehicle at high speed. Therefore, the present application proposes to limit the variable steering characteristic coefficient φ, and uses the critical vehicle speed u cr as the limiting condition. The steering characteristic coefficient of the vehicle when the excessive steering occurs is derived by the critical vehicle speed u cr , and is used as the maximum excessive steering limit condition of the variable steering characteristic coefficient φ, and a safety coefficient τ is designed to reserve a certain safety margin. The maximum insufficient steering limit condition of the variable steering characteristic coefficient φ is the steering characteristic coefficient when the original vehicle has no active control. Therefore, the limiting condition of the variable steering characteristic coefficient φ is as follows:

[0095] By limiting the variable steering characteristic coefficient, the steering sensitivity of the vehicle can be improved while the stability is considered.

[0096] In some embodiments of the present application, as shown in FIG. 4, the additional yaw moment is obtained according to the ideal center of mass side slip angle, the corrected ideal yaw rate, and the actual center of mass side slip angle and the actual yaw rate of the vehicle, and includes:

[0097] S221, limiting the ideal center of mass side slip angle and the corrected ideal yaw rate by using the road adhesion coefficient of the road on which the vehicle is located to obtain a reference center of mass side slip angle and a reference yaw rate.

[0098] The road adhesion coefficient can be estimated by the vehicle controller and obtained by the electronic device from the vehicle controller, or can be estimated by the electronic device itself.

[0099] S222, obtaining the additional yaw moment according to the reference center of mass side slip angle, the reference yaw rate, and the actual center of mass side slip angle and the actual yaw rate.

[0100] In this embodiment, the additional yaw moment is obtained according to the reference center of mass side slip angle, the reference yaw rate, and the actual center of mass side slip angle and the actual yaw rate, and includes: calculating a first difference value between the reference yaw rate and the actual yaw rate, and calculating a second difference value between the reference center of mass side slip angle and the actual center of mass side slip angle; using a preset closed-loop control algorithm (such as a PID control algorithm, a fuzzy control algorithm, a fuzzy PID control algorithm, etc.) to obtain the additional yaw moment according to the first difference value and the second difference value.

[0101] For example, the first difference value and the second difference value can be input into two corresponding controllers, and the two controllers output respective additional yaw moments, and then the two additional yaw moments are weighted to obtain a final additional yaw moment for subsequent torque distribution; the first difference value and the second difference value can also be input into a controller, and the controller outputs an additional yaw moment for subsequent torque distribution.

[0102] In some examples, limiting the ideal yaw rate by using the road adhesion coefficient to obtain the reference yaw rate includes: determining a maximum yaw rate according to the road adhesion coefficient; comparing the ideal yaw rate with the maximum yaw rate; if the ideal yaw rate is greater than the maximum yaw rate, taking the maximum yaw rate as the reference yaw rate; and if the ideal yaw rate is less than or equal to the maximum yaw rate, taking the ideal yaw rate as the reference yaw rate.

[0103] The maximum yaw rate can be wherein μ is the road adhesion coefficient, g is the acceleration of gravity, u is the vehicle speed of the vehicle, and η is a preset safety coefficient, the value of which can be set as needed, and the value range can be [0.8, 1].

[0104] Similarly, the ideal center side slip angle is corrected by the road adhesion coefficient to obtain a reference center side slip angle, including: determining a maximum center side slip angle according to the road adhesion coefficient; comparing the ideal center side slip angle with the maximum center side slip angle; if the ideal center side slip angle is greater than the maximum center side slip angle, taking the maximum center side slip angle as the reference center side slip angle; if the ideal center side slip angle is less than or equal to the maximum center side slip angle, taking the ideal center side slip angle as the reference center side slip angle.

[0105] wherein the maximum center side slip angle is tan -1 0.02μg, wherein μ is the road adhesion coefficient and g is the gravity acceleration.

[0106] In this embodiment, after the ideal center side slip angle and the corrected ideal yaw rate are obtained, the road condition is further corrected, and the longitudinal acceleration a y of the vehicle needs to be calculated. y The longitudinal acceleration a y is represented by the following formula:

[0107] And a rd ≤μg is satisfied.

[0108] Since the actual center side slip angle β of the vehicle is small when the vehicle is running, the last two terms in the formula are small, and are ignored for simple calculation. However, other factors exist in the actual running process, and a certain stability margin, such as 10%, can be reserved according to design experience, so that the corrected ideal yaw rate limit formula is as follows:

[0109] At the same time, the ideal center side slip angle limit formula β rd ≤tan -1 0.02μg can be obtained according to the tire model data and experience of the vehicle.

[0110] The ideal center side slip angle and the corrected ideal yaw rate obtained above are limited by the above limit formula, and the reference center side slip angle and the reference yaw rate are obtained. Then, the deviation between the reference yaw rate and the reference center side slip angle and the actual yaw rate and the center side slip angle of the vehicle is taken as the input of a preset controller (such as a PID controller) to calculate the additional yaw moment M z,req required by the vehicle to follow the reference value.

[0111] By limiting the ideal center side slip angle by the road adhesion coefficient and limiting the corrected ideal yaw rate, the steering sensitivity and stability of the vehicle can be further improved.

[0112] For the convenience of understanding, the control method of the vehicle of the present application is described below by means of a specific embodiment in combination with FIG. 5 and FIG. 6.

[0113] As shown in FIG. 5, the control method of the vehicle comprises:

[0114] S51, determining that the vehicle starts the track mode.

[0115] S52, acquiring the actual yaw rate and obtaining the actual center of mass side slip angle according to the center of mass lateral speed and the center of mass longitudinal speed.

[0116] S53, obtaining the reference yaw rate and the reference center of mass side slip angle based on the ideal reference model according to the expected steering characteristic information, the steering wheel angle, the vehicle speed, the road adhesion coefficient, etc.

[0117] Referring to FIG. 5, the step S52 and the step S53 can be executed in parallel to reduce the control time.

[0118] As shown in FIG. 6, the step S53 can comprise:

[0119] S61, obtaining the variable steering characteristic coefficient according to the expected steering characteristic information;

[0120] S62, limiting the variable steering characteristic coefficient;

[0121] S63, correcting the ideal yaw rate obtained by the ideal reference model according to the limited variable steering characteristic coefficient;

[0122] S64, limiting the ideal center of mass side slip angle and the corrected ideal yaw rate obtained by the ideal reference model respectively by using the road adhesion coefficient to obtain the reference center of mass side slip angle and the reference yaw rate.

[0123] S54, calculating the first difference value between the reference yaw rate and the actual yaw rate and calculating the second difference value between the reference center of mass side slip angle and the actual center of mass side slip angle.

[0124] S55, obtaining the additional yaw moment by using a preset PID controller according to the first difference value and the second difference value.

[0125] S56, distributing the torque of each driving motor of the vehicle according to the additional yaw moment by using a torque distribution controller.

[0126] The distribution mode can adopt the dynamic load distribution algorithm described above or the distribution method based on the total driving torque of the driving shaft described above.

[0127] The control method of the vehicle according to the embodiment of the application obtains a variable steering characteristic coefficient according to the expected steering characteristic information, limits the variable steering characteristic coefficient, and then corrects the ideal yaw rate by using the limited variable steering characteristic coefficient; limits the ideal mass center side slip angle obtained by the ideal reference model and the corrected ideal yaw rate by using the road adhesion coefficient, to obtain a reference mass center side slip angle and a reference yaw rate; and finally, torque distribution is performed based on the reference mass center side slip angle, the reference yaw rate, the actual mass center side slip angle and the actual yaw rate, and the advantage of the distributed drive vehicle that the vehicle motion posture can be controlled with great freedom is utilized in the torque distribution. Thus, the vehicle tends to slightly over-steer, so that the driver can obtain higher steering sensitivity and maneuverability, the higher requirements of the driver on the vehicle maneuverability are met, and the stability can be considered.

[0128] Fig. 7 is a structural block diagram of the control device of the vehicle according to the embodiment of the application.

[0129] As shown in Fig. 7, the control device 700 of the vehicle includes a correction module 710, a processing module 720 and a distribution module 730.

[0130] The correction module 710 is configured to correct the ideal yaw rate according to the expected steering characteristic information; the processing module 720 is configured to obtain an additional yaw moment according to the ideal mass center side slip angle, the corrected ideal yaw rate, the actual mass center side slip angle and the actual yaw rate of the vehicle; and the distribution module 730 is configured to perform torque distribution based on the additional yaw moment.

[0131] In some embodiments of the application, the correction of the ideal yaw rate according to the expected steering characteristic information includes obtaining a variable steering characteristic coefficient according to the expected steering characteristic information, and correcting the ideal yaw rate according to the variable steering characteristic coefficient.

[0132] In some embodiments of the application, the expected steering characteristic information includes an expected steering characteristic value θ, and the obtaining of the variable steering characteristic coefficient according to the expected steering characteristic information includes:

[0133] When θ is greater than 0, the variable steering characteristic coefficient is θ*K;

[0134] When θ is equal to 0, the variable steering characteristic coefficient is 0;

[0135] When θ is less than 0, the variable steering characteristic coefficient is

[0136] K is a stability factor, τ is a preset safety coefficient, u is a vehicle speed, and θ is an expected steering characteristic value. cr is a critical vehicle speed when the vehicle is in an over-steering state and an abrupt turning condition occurs.

[0137] In some embodiments of the present application, before the ideal yaw rate is corrected according to the variable steering characteristic coefficient, the method further comprises limiting the variable steering characteristic coefficient by:

[0138] comparing the variable steering characteristic coefficient with and K respectively;

[0139] if the variable steering characteristic coefficient is less than , the variable steering characteristic coefficient is limited to

[0140] if the variable steering characteristic coefficient is greater than K, the variable steering characteristic coefficient is limited to K;

[0141] if the variable steering characteristic coefficient is greater than or equal to and less than or equal to K, the variable steering characteristic coefficient is kept unchanged.

[0142] In some embodiments of the present application, the ideal yaw rate is corrected according to the variable steering characteristic coefficient, which comprises: replacing the stability factor used for calculating the ideal yaw rate with the variable steering characteristic coefficient to achieve the correction of the ideal yaw rate.

[0143] In some embodiments of the present application, the additional yaw moment is obtained according to the ideal center of mass side slip angle, the corrected ideal yaw rate, and the actual center of mass side slip angle and the actual yaw rate of the vehicle, which comprises: limiting the ideal center of mass side slip angle and the corrected ideal yaw rate by using the road adhesion coefficient of the road on which the vehicle is located to obtain a reference center of mass side slip angle and a reference yaw rate; and obtaining the additional yaw moment according to the reference center of mass side slip angle, the reference yaw rate, and the actual center of mass side slip angle and the actual yaw rate.

[0144] In some embodiments of the present application, the ideal yaw rate is limited by using the road adhesion coefficient to obtain a reference yaw rate, which comprises: determining a maximum yaw rate according to the road adhesion coefficient; comparing the ideal yaw rate with the maximum yaw rate; if the ideal yaw rate is greater than the maximum yaw rate, the maximum yaw rate is taken as the reference yaw rate; and if the ideal yaw rate is less than or equal to the maximum yaw rate, the ideal yaw rate is taken as the reference yaw rate.

[0145] wherein the maximum yaw rate is μ is the road adhesion coefficient, g is the acceleration of gravity, u is the vehicle speed of the vehicle, and η is a preset safety coefficient.

[0146] In some embodiments of the present application, the ideal center side slip angle is respectively corrected by using a road adhesion coefficient to obtain a reference center side slip angle, including: determining a maximum center side slip angle according to the road adhesion coefficient; comparing the ideal center side slip angle with the maximum center side slip angle; if the ideal center side slip angle is greater than the maximum center side slip angle, taking the maximum center side slip angle as the reference center side slip angle; if the ideal center side slip angle is less than or equal to the maximum center side slip angle, taking the ideal center side slip angle as the reference center side slip angle.

[0147] wherein the maximum center side slip angle is tan -1 0.02 μg, μ is the road adhesion coefficient, and g is the acceleration of gravity.

[0148] In some embodiments of the present application, the additional yaw moment is obtained according to the reference center side slip angle, the reference yaw rate, the actual center side slip angle, and the actual yaw rate, including: calculating a first difference between the reference yaw rate and the actual yaw rate, and calculating a second difference between the reference center side slip angle and the actual center side slip angle; obtaining the additional yaw moment according to the first difference and the second difference by using a preset closed-loop control algorithm.

[0149] In some embodiments of the present application, the vehicle is a distributed drive vehicle; and the torque distribution is performed based on the additional yaw moment, including:

[0150] The torque distribution is performed by the following formula:

[0151] wherein T reqL and T reqR are the distributed torque of the left drive motor and the distributed torque of the right drive motor, respectively, T reqAXLE is the total drive torque of the drive shaft, R w is the wheel rolling radius, B is the drive shaft wheelbase, i L and i R are the reduction ratio of the left drive motor and the reduction ratio of the right drive motor, respectively, and M z,req is the additional yaw moment.

[0152] It should be noted that other specific embodiments of the control device of the vehicle of the present application can refer to the specific embodiments of the control method of the vehicle of the present application.

[0153] FIG. 8 is a structural block diagram of the vehicle of the present application.

[0154] As shown in FIG. 8, the vehicle 800 includes the control device 700 of the vehicle of the above embodiments.

[0155] Based on the control method of the vehicle of the above embodiments, the present application proposes a computer readable storage medium.

[0156] In this embodiment, a computer program is stored on a computer-readable storage medium, and the computer program, when executed by a processor, implements the control method of the vehicle of the above embodiment.

[0157] Based on the control method of the vehicle of the above embodiment, the present application further proposes a computer program product.

[0158] In this embodiment, the computer program product includes a computer program, and the computer program, when executed by a processor, implements the control method of the vehicle of the above embodiment.

[0159] It should be noted that the logic and / or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a list of executable instructions for implementing logic functions, and can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor- based system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions, or in conjunction with which the instructions can be executed. For the purposes of this specification, a "computer-readable medium" can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium include the following: an electrical connection having one or more wires (electrical apparatus), a portable computer diskette (magnetic apparatus), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber (optical apparatus), and a portable compact disc read-only memory (CDROM). In addition, the computer-readable medium can even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, for example, by optically scanning the paper or other suitable medium, then electronically converted into a form that is suitable for use by the instruction execution system, apparatus, or device, and then stored in the computer memory.

[0160] It should be understood that parts of the present application can be realized by hardware, software, firmware, or a combination thereof. In the above-described embodiments, a plurality of steps or methods can be realized by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if realized by hardware, and as in another embodiment, any one or a combination of the following technologies known in the art can be used: discrete logic circuitry having logic gates for implementing logic functions on data signals, application specific integrated circuits having appropriate combinational logic gates, programmable gate arrays (PGA), field programmable gate arrays (FPGA), and the like.

[0161] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0162] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like is based on the orientation or positional relationship shown in the drawings, and is only for the purpose of facilitating the description of the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0163] In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0164] In the present application, unless otherwise specifically defined and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixed connection, or detachable connection, or integral; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise specifically limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0165] In the present application, unless otherwise explicitly specified and limited, a first feature is "on" or "under" a second feature can mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature is "over", "above" and "on top of" the second feature can mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature. The first feature is "under", "below" and "underneath" the second feature can mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is horizontally lower than the second feature.

[0166] Although the embodiments of the present application have been shown and described above, it is to be understood that the above-described embodiments are exemplary only, and are not to be construed as limiting the present application, and that changes, modifications, substitutions and variations can be made thereto by those skilled in the art without departing from the scope of the present application.

Claims

1. A control method of a vehicle, characterized by, The method comprises: correcting the ideal yaw rate according to expected steering characteristic information; obtaining an additional yaw moment according to the ideal center of mass side slip angle, the corrected ideal yaw rate, and actual center of mass side slip angle and actual yaw rate of the vehicle; performing torque distribution based on the additional yaw moment.

2. The method of claim 1, wherein, The correction of the ideal yaw rate according to the expected steering characteristic information comprises: obtaining a variable steering characteristic coefficient according to the expected steering characteristic information; correcting the ideal yaw rate according to the variable steering characteristic coefficient.

3. The method of claim 2, wherein, The expected steering characteristic information comprises an expected steering characteristic value θ, and the obtaining of the variable steering characteristic coefficient according to the expected steering characteristic information comprises: when θ is greater than 0, obtaining the variable steering characteristic coefficient as θ*K; when θ is equal to 0, obtaining the variable steering characteristic coefficient as 0. When θ is smaller than 0, the variable steering characteristic coefficient is obtained as Wherein, K is stability factor, τ is preset safety factor, u cr is the critical vehicle speed when the vehicle is in the over-steering state and the sudden turning condition occurs.

4. The method of claim 3, wherein, Before the correction of the ideal yaw rate according to the variable steering characteristic coefficient, the method further comprises limiting the variable steering characteristic coefficient by: the variable steering characteristic coefficients are respectively multiplied by comparing the variable steering characteristic coefficient with K; if the variable steering characteristic coefficient is less than the variable steering characteristic coefficient is limited to if the variable steering characteristic coefficient is greater than K, limiting the variable steering characteristic coefficient to K; if the variable steering characteristic coefficient is greater than or equal to and if the variable steering characteristic coefficient is less than or equal to K, keeping the variable steering characteristic coefficient unchanged.

5. The method according to any one of claims 2-4, characterized in that, The correction of the ideal yaw rate according to the variable steering characteristic coefficient comprises: replacing a stability factor used for calculating the ideal yaw rate with the variable steering characteristic coefficient to correct the ideal yaw rate.

6. The method according to any one of claims 1 to 5, characterized in that, The obtaining of the additional yaw moment according to the ideal center of mass side slip angle, the corrected ideal yaw rate, and actual center of mass side slip angle and actual yaw rate of the vehicle comprises: limiting the ideal center of mass side slip angle and the corrected ideal yaw rate respectively by using a road adhesion coefficient of a road on which the vehicle is located to obtain a reference center of mass side slip angle and a reference yaw rate; obtaining the additional yaw moment according to the reference center of mass side slip angle, the reference yaw rate, and the actual center of mass side slip angle and the actual yaw rate.

7. The method of claim 6, wherein, The limiting of the ideal yaw rate by using the road adhesion coefficient to obtain the reference yaw rate comprises: determining a maximum yaw rate according to the road adhesion coefficient; comparing the ideal yaw rate with the maximum yaw rate; if the ideal yaw rate is greater than the maximum yaw rate, taking the maximum yaw rate as the reference yaw rate; if the ideal yaw rate is less than or equal to the maximum yaw rate, taking the ideal yaw rate as the reference yaw rate.

8. The method according to claim 6 or 7, characterized in that, The correction of the ideal center of mass side slip angle by using the road adhesion coefficient to obtain the reference center of mass side slip angle comprises: determining a maximum center of mass side slip angle according to the road adhesion coefficient; comparing the ideal center of mass side slip angle with the maximum center of mass side slip angle; if the ideal center of mass side slip angle is greater than the maximum center of mass side slip angle, taking the maximum center of mass side slip angle as the reference center of mass side slip angle; if the ideal center of mass side slip angle is less than or equal to the maximum center of mass side slip angle, taking the ideal center of mass side slip angle as the reference center of mass side slip angle.

9. The method according to claim 7 or 8, characterized in that, The maximum yaw angular velocity is wherein μ is the road adhesion coefficient, g is the acceleration of gravity, u is the vehicle speed of the vehicle, and η is a preset safety coefficient.

10. The method according to claim 8 or 9, characterized in that, The maximum centroid side slip angle is tan -1 0.02μg, where μ is the road adhesion coefficient and g is the acceleration due to gravity.

11. The method according to any one of claims 6-10, characterized in that, The additional yaw moment is obtained according to the reference side slip angle, the reference yaw rate, the actual side slip angle and the actual yaw rate, and the method comprises the steps of: calculating a first difference between the reference yaw rate and the actual yaw rate, and calculating a second difference between the reference side slip angle and the actual side slip angle; obtaining the additional yaw moment according to the first difference and the second difference by using a preset closed-loop control algorithm.

12. The method according to any one of claims 1 to 11, characterized in that, The vehicle is a distributed drive vehicle. The torque distribution based on the additional yaw moment comprises the steps of: Torque distribution is performed by the following equation: In the formula, T reqL and T reqR are the distribution torques of the left and right drive motors of the vehicle, respectively, T reqAXLE is the total drive torque of the drive shaft, R w is the rolling radius of the wheel, B is the wheel base of the drive shaft, i L and i R are the reduction ratios of the left and right drive motors, respectively, M z,req is the additional yaw moment.

13. A control device of a vehicle characterized by comprising: comprising: a correction module configured to correct the ideal yaw rate according to expected steering characteristic information; a processing module configured to obtain an additional yaw moment according to an ideal side slip angle, the corrected ideal yaw rate, an actual side slip angle of the vehicle and an actual yaw rate of the vehicle; a distribution module configured to distribute torque based on the additional yaw moment.

14. A vehicle characterized by comprising: comprising: The control device of the vehicle according to claim 13.

15. A computer readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the method according to any one of claims 1-12.

16. A computer program product comprising a computer program, characterized in that, The computer program is executed by the processor to implement the method according to any one of claims 1-12.

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