Vehicle control method, vehicle control device, vehicle control system and storage medium

Abstract

The invention discloses a vehicle control method, a vehicle control device, a vehicle control system and a computer readable storage medium. The embodiment of the invention discloses a vehicle control method. The current yaw velocity and the current side slip angle of the vehicle are obtained; acquiring a target yaw velocity and a target side slip angle of the vehicle; and independently controlling a plurality of front wheels and / or a plurality of rear wheels in the vehicle according to the current yaw velocity, the current side slip angle, the target yaw velocity and the target side slip angle. Therefore, the yaw velocity and the side slip angle of the vehicle can be controlled at the same time, the yaw amplitude and the course angle offset of the vehicle are reduced, and the running stability of the vehicle is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a vehicle control method, a vehicle control device, a vehicle control system and a computer-readable storage medium. Background Art

[0002] When a vehicle is driving on an unstable road (such as a split road), the longitudinal forces on each side of the vehicle will be different, causing the vehicle to become unstable during driving, which can easily lead to traffic accidents during emergency acceleration or emergency braking, endangering the safety of the driver. The instability of the vehicle is mainly related to the yaw rate and the sideslip angle of the center of mass. The current vehicle control method only controls the stability of the vehicle by controlling the sideslip angle of the center of mass or the yaw rate, which has very limited effect on improving the vehicle's handling stability. Summary of the invention

[0003] The embodiments of the present application provide a vehicle control method, a vehicle control device, a vehicle control system and a computer-readable storage medium to solve at least one of the above-mentioned technical problems.

[0004] The vehicle control method of the embodiment of the present application includes:

[0005] Obtaining a current yaw rate and a current sideslip angle of the vehicle;

[0006] Obtaining a target yaw rate and a target center-of-mass sideslip angle of the vehicle;

[0007] A plurality of front wheels and / or a plurality of rear wheels in the vehicle are independently controlled according to the current yaw rate, the current sideslip angle of the center of mass, the target yaw rate and the target sideslip angle of the center of mass.

[0008] In some embodiments, the vehicle control method further includes:

[0009] Acquiring a current sensor signal of the vehicle, wherein the current sensor signal includes a current yaw angular acceleration and a current vehicle speed;

[0010] The obtaining of the current yaw rate and the current sideslip angle of the center of mass of the vehicle comprises:

[0011] Calculating the current yaw angular velocity according to the current yaw angular acceleration;

[0012] The current center of mass sideslip angle is calculated according to the current vehicle speed.

[0013] In some embodiments, the vehicle control method further includes:

[0014] Acquiring a current sensor signal of the vehicle, wherein the current sensor signal includes a current front wheel steering angle signal;

[0015] The obtaining of a target yaw rate and a target center-of-mass sideslip angle of the vehicle comprises:

[0016] Calculating a desired yaw rate and a desired sideslip angle of the center of mass according to the current front wheel steering angle signal;

[0017] The target yaw rate and the target sideslip angle of the center of mass are determined according to the desired yaw rate and the desired sideslip angle of the center of mass.

[0018] In some embodiments, independently controlling a plurality of front wheels and / or a plurality of rear wheels in the vehicle according to the current yaw rate, the current sideslip angle of the center of mass, the target yaw rate, and the target sideslip angle of the center of mass includes:

[0019] Calculating a first steering angle and a second steering angle respectively corresponding to two rear wheels of the vehicle according to the current yaw rate, the current sideslip angle of the center of mass, the target yaw rate and the target sideslip angle of the center of mass;

[0020] The steering of the two rear wheels is controlled according to the first steering angle and the second steering angle.

[0021] In some embodiments, the calculating the first steering angle and the second steering angle respectively corresponding to the two rear wheels of the vehicle according to the current yaw rate, the current center of mass sideslip angle, the target yaw rate and the target center of mass sideslip angle comprises:

[0022] A first steering angle and a second steering angle respectively corresponding to two rear wheels in the vehicle are determined according to the current yaw angular velocity, the current sideslip angle of the center of mass, the target yaw angular velocity and the target sideslip angle of the center of mass, so as to minimize the tracking error between the current yaw angular velocity and the target yaw angular velocity, and between the current sideslip angle and the target sideslip angle of the center of mass.

[0023] In some embodiments, controlling the steering of the two rear wheels according to the first steering angle and the second steering angle includes:

[0024] determining whether the first steering angle and the second steering angle are within a predetermined angle control range;

[0025] When the first steering angle and the second steering angle are within the predetermined angle control range, controlling the current steering angles of the two rear wheels according to the first steering angle and the second steering angle;

[0026] When the first steering angle and the second steering angle are not within the predetermined angle control range, the current steering angles of the two rear wheels are controlled to decrease to zero at a preset rate.

[0027] In some embodiments, the predetermined angle control range corresponding to the first steering angle is [-10°, +10°]; and / or

[0028] The predetermined angle control range corresponding to the second steering angle is [-10°, +10°].

[0029] In certain embodiments, after controlling the current steering angles of the two rear wheels according to the first steering angle and the second steering angle, and / or before obtaining the current yaw rate and the current sideslip angle of the vehicle, the vehicle control method further includes:

[0030] Determining whether the vehicle is currently on an unstable road surface;

[0031] When the vehicle is currently on the unstable road surface, the step of obtaining the current yaw rate and the current sideslip angle of the center of mass of the vehicle is performed.

[0032] In certain embodiments, the unstable road surface includes a split road surface, a butt-jointed road surface, a checkerboard road surface, or an icy and snowy slope road surface.

[0033] The vehicle control device according to the embodiment of the present application includes:

[0034] A state estimation module, used to obtain a current yaw rate and a current sideslip angle of the center of mass of the vehicle;

[0035] A calculation control module is used to obtain a target yaw rate and a target sideslip angle of the center of mass of the vehicle, and independently control a plurality of front wheels and / or a plurality of rear wheels in the vehicle according to the current yaw rate, the current sideslip angle of the center of mass, the target yaw rate and the target sideslip angle of the center of mass.

[0036] The vehicle control system of the implementation mode of the present application includes one or more processors and a memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, the vehicle control method of any of the above implementation modes is implemented.

[0037] The computer-readable storage medium of the embodiment of the present application stores a computer program thereon, and is characterized in that when the program is executed by a processor, the vehicle control method of any of the above-mentioned embodiments is implemented.

[0038] The vehicle control method, vehicle control device, vehicle control system and computer-readable storage medium of the embodiment of the present application acquire the current yaw rate and current center of mass sideslip angle of the vehicle, as well as the target yaw rate and target center of mass sideslip angle of the vehicle, and independently control multiple front wheels and / or multiple rear wheels according to the current yaw rate, current center of mass sideslip angle, target yaw rate and target center of mass sideslip angle. In this way, the yaw rate and center of mass sideslip angle of the vehicle can be controlled simultaneously, the yaw amplitude and heading angle deviation of the vehicle can be reduced, and the driving stability of the vehicle can be improved.

[0039] Additional aspects and advantages of the embodiments of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0041] Figure 1 is a flow chart of a vehicle control method according to certain embodiments of the present application;

[0042] Figure 2 is a flow chart of a vehicle control method according to certain embodiments of the present application;

[0043] Figure 3 is a schematic diagram of a vehicle in an unstable state according to certain embodiments of the present application;

[0044] Figure 4 is a schematic diagram of the relationship between the rear wheel turning angle, yaw moment and center of mass sideslip angle on a low-adhesion road surface in certain embodiments of the present application;

[0045] Figure 5 is a schematic diagram of the relationship between the rear wheel turning angle, yaw moment and center of mass sideslip angle on a high-adhesion road surface in certain embodiments of the present application;

[0046] Figure 6 is a flow chart of a vehicle control method according to certain embodiments of the present application;

[0047] Figure 7 is a flow chart of a vehicle control method according to certain embodiments of the present application;

[0048] Figure 8 is a flow chart of a vehicle control method according to certain embodiments of the present application;

[0049] Fig. 9 is a flow chart of a vehicle control method according to certain embodiments of the present application;

[0050] Fig.10is a flow chart of a vehicle control method according to certain embodiments of the present application;

[0051] Fig.11 is a flow chart of a vehicle control method according to certain embodiments of the present application;

[0052] Fig.12 is a module schematic diagram of a vehicle control device according to certain embodiments of the present application;

[0053] Fig.13 is a module schematic diagram of a vehicle control device according to certain embodiments of the present application;

[0054] Fig.14 is a schematic diagram of a module of a vehicle control system according to certain embodiments of the present application;

[0055] Fig.15 It is a schematic diagram of the connection status between a computer-readable storage medium and a processor in certain embodiments of the present application. DETAILED DESCRIPTION

[0056] The following is a further description of the embodiments of the present application in conjunction with the accompanying drawings. The same or similar reference numerals in the accompanying drawings represent the same or similar elements or elements with the same or similar functions from beginning to end. In addition, the embodiments of the present application described below in conjunction with the accompanying drawings are exemplary and are only used to explain the embodiments of the present application, and cannot be understood as limiting the present application.

[0057] See also Figure 1 and Figure 2 , the embodiment of the present application provides a vehicle control method, including:

[0058] 010: Get the current yaw rate and sideslip angle of the vehicle;

[0059] 020: Get the target yaw rate and target sideslip angle of the vehicle;

[0060] 030: Independently control multiple front wheels and / or multiple rear wheels in the vehicle according to the current yaw rate, the current center of mass sideslip angle, the target yaw rate and the target center of mass sideslip angle.

[0061] The vehicle control method of the embodiment of the present application obtains the current yaw rate and the current center of mass sideslip angle of the vehicle, as well as the target yaw rate and the target center of mass sideslip angle of the vehicle, and independently controls multiple front wheels and / or multiple rear wheels according to the current yaw rate, the current center of mass sideslip angle, the target yaw rate and the target center of mass sideslip angle. In this way, the yaw rate and the center of mass sideslip angle of the vehicle can be controlled simultaneously, the yaw amplitude and the heading angle deviation of the vehicle can be reduced, and the driving stability of the vehicle can be improved.

[0062] When a vehicle is driving on an unstable road, during the acceleration or braking process, due to the inconsistency of the road adhesion coefficients of each wheel, an additional yaw force will be generated to cause the vehicle to rotate around the center of mass, and the vehicle will become unstable. Figure 3 As shown, the left side is a low-adhesion road, the right side is a high-adhesion road, and the vehicle is driven by four-wheel drive. Figure 4 and Figure 5 When a vehicle is traveling on a high-adhesion road surface, at the same wheel rotation angle, a larger yaw moment will be generated compared to a low-adhesion road surface. Therefore, when a vehicle is traveling on an unstable road surface, the yaw angular velocity of each wheel may be different. When the vehicle starts and accelerates on the above-mentioned split road surface, the driving wheel on the left road surface will slip, and the vehicle will generate a yaw moment rotating counterclockwise, causing yaw.

[0063] The instability state is mainly related to the yaw rate and the sideslip angle of the center of mass. The greater the yaw rate, the faster the vehicle rotates laterally around the center of mass. The sideslip angle of the center of mass is characterized by the lateral driving speed and the longitudinal driving speed. The greater the sideslip angle of the center of mass, the greater the deviation of the vehicle from the target driving trajectory. Therefore, it is necessary to control the yaw rate and the sideslip angle of the center of mass to stabilize the vehicle's driving trajectory.

[0064] Specifically, the current yaw rate and the current sideslip angle of the center of mass of the vehicle can be obtained, and the target yaw rate and the target sideslip angle of the center of mass of the vehicle can be obtained, wherein the order of obtaining the two is not limited. Multiple front wheels and / or multiple rear wheels in the vehicle are independently controlled according to the current yaw rate, the current sideslip angle of the center of mass, the target yaw rate and the target sideslip angle of the center of mass. For example, multiple front wheels in the vehicle can be independently controlled according to the above parameters; or multiple rear wheels in the vehicle can be independently controlled; or multiple front wheels and multiple rear wheels in the vehicle can be independently controlled. Multiple refers to two or more.

[0065] It should be noted that, according to the current yaw rate, the current sideslip angle of the center of mass, the target yaw rate and the target sideslip angle of the center of mass, the multiple front wheels and / or the multiple rear wheels in the vehicle can be independently controlled for steering, and the driving of the multiple front wheels and / or the multiple rear wheels in the vehicle can also be independently controlled. Independently controlling the multiple front wheels and / or the multiple rear wheels in the vehicle for steering means: for the wheels on the road surface with different adhesion coefficients, the steering motor applies different steering torques to control the multiple front wheels and / or the multiple rear wheels to rotate to different angles to stabilize the vehicle. Independently controlling the driving of the multiple front wheels and / or the multiple rear wheels in the vehicle means: for the wheels on the road surface with different adhesion coefficients, the drive motor applies different sizes of driving force to drive the multiple front wheels and / or the multiple rear wheels to prevent the vehicle from swaying.

[0066] In the related technology, an active rear-wheel steering system is used to reduce the additional yaw rate or center of mass slip angle generated during the vehicle instability process, thereby stabilizing the vehicle's driving trajectory. The active rear-wheel steering system has only one control variable, the rear wheel angle, and can only select one of the yaw rate and the center of mass slip angle as the control target. It controls multiple rear wheels together, and multiple rear wheels can only turn in the same direction. Both the yaw rate and the center of mass slip angle will have a significant impact on the stability of the vehicle's driving, and the two have a mutual influence. Figure 4 As shown in the figure, when the yaw moment of the vehicle is zero, the center of mass slip angle may be large, and the vehicle is still in an unstable state. If only the yaw rate is controlled, the center of mass slip angle is large, and vice versa, if only the center of mass slip angle is controlled, the yaw angle is large. Therefore, using the yaw rate or the center of mass slip angle as a single control target will have a very limited effect on improving the vehicle's handling stability.

[0067] In the implementation manner of the present application, taking the independent control of steering of multiple front wheels and / or multiple rear wheels in a vehicle as an example, when the center of mass sideslip angle is fixed at zero, the yaw moment can be effectively improved by adjusting the steering angle of the wheel, thereby improving the yaw rate. Therefore, the control characteristics of independent wheel steering can be utilized to achieve simultaneous control of the center of mass sideslip angle and yaw rate by independently steering multiple wheels. Specifically, multiple front wheels and / or multiple rear wheels can be independently controlled according to the current yaw rate, the current center of mass sideslip angle, the target yaw rate and the target center of mass sideslip angle. In this way, when the vehicle is traveling on an unstable road surface, it is possible to achieve simultaneous control of the vehicle's yaw rate and center of mass sideslip angle, reduce the vehicle's yaw amplitude and heading angle offset, and improve the vehicle's driving stability.

[0068] In certain embodiments, the unstable road surface includes a split road surface, a butt-jointed road surface, a checkerboard road surface, or an ice and snow slope road surface.

[0069] Specifically, a road surface where the adhesion coefficients of the road surface where the left and right wheels of a vehicle are located are inconsistent is a split road surface, such as an asphalt road surface with water accumulation. When a vehicle is traveling on a split road surface, the left wheel is traveling on a dry asphalt road surface, and the right wheel is traveling on a water-logged road surface. The adhesion coefficients of the road surfaces where the wheels on both sides are located are different, and the vehicle is prone to instability. A road surface where the adhesion coefficients of the road surface where the front and rear wheels of a vehicle are located are inconsistent is a butt-jointed road surface. When a vehicle is traveling on a butt-jointed road surface, the adhesion coefficients of the road surfaces where the front and rear wheels of a vehicle are located are different, and the vehicle is prone to instability. A road surface where the road surfaces with different adhesion coefficients are distributed in a chessboard shape is a chessboard road surface, such as an asphalt road surface with water accumulation. When a vehicle is traveling on a chessboard road surface, the left front wheel and the right rear wheel are traveling on a dry asphalt road surface, and the right front wheel and the left rear wheel are traveling on a water-logged road surface. The adhesion coefficients of the road surfaces where the wheels are located may be inconsistent, and the vehicle is prone to instability. The road surface conditions of an ice and snow slope are relatively complex, such as different bumps or ice protrusions. When a vehicle is traveling on an ice and snow slope, the adhesion coefficients of the road surfaces where the wheels are located may be inconsistent, and the vehicle is prone to instability.

[0070] The following describes in detail the process of independently controlling the steering of multiple front wheels and / or multiple rear wheels in the vehicle according to the current yaw rate, the current sideslip angle of the center of mass, the target yaw rate and the target sideslip angle of the center of mass by taking the independent control of the steering of two rear wheels as an example.

[0071] See also Figure 2 and Figure 6 In some embodiments, the vehicle control method further includes:

[0072] 040: Acquire a current sensor signal of the vehicle, wherein the current sensor signal includes a current yaw angular acceleration and a current vehicle speed;

[0073] At this time, the current yaw rate and the current sideslip angle of the center of mass of the vehicle (ie 010) are obtained, including:

[0074] 011: Calculate the current yaw rate based on the current yaw acceleration;

[0075] 012: Calculate the current sideslip angle of the center of mass based on the current vehicle speed.

[0076] Among them, the current sensor signal may include the current vehicle speed, wheel speed, electronic parking brake (EPB) system activation state, accelerator pedal signal, brake pedal signal, front wheel / rear wheel steering angle signal, suspension height, yaw angular acceleration and lateral acceleration, etc. The current yaw angular velocity can be calculated based on the current yaw acceleration, and the calculation formula is as follows:

[0077]

[0078] Among them, ω r is the yaw angular velocity, is the yaw angular acceleration.

[0079] In addition, the current vehicle speed includes lateral (such as Figure 3 Y axis direction) vehicle speed and longitudinal direction (such as Figure 3 The vehicle speed in the X-axis direction can be calculated based on the lateral speed and longitudinal speed to obtain the current center of mass sideslip angle. The calculation formula is as follows:

[0080]

[0081] Where β is the sideslip angle of the center of mass, V y is the lateral speed, V x is the longitudinal speed.

[0082] See also Figure 3 and Figure 7 In some embodiments, the vehicle control method further includes:

[0083] 050: Acquire a current sensor signal of the vehicle, wherein the current sensor signal includes a current front wheel steering angle signal;

[0084] At this time, the target yaw rate and target center of mass sideslip angle (ie 020) of the vehicle are obtained, including:

[0085] 021: Calculate the expected yaw rate and the expected sideslip angle of the center of mass according to the current front wheel steering angle signal;

[0086] 022: Determine a target yaw rate and a target sideslip angle according to a desired yaw rate and a desired sideslip angle.

[0087] Specifically, when the vehicle is in an unstable state, Figure 3 For example, the driver will control the front wheel steering system through the steering wheel to turn the front wheel to the right, so that the target yaw rate and target center of mass sideslip angle can be determined by the current front wheel turning angle to calculate the angles that the two rear wheels need to turn, that is, the first steering angle and the second steering angle. The left rear wheel and right rear wheel steering motors apply steering torque to make the steering angle reach the preset state until the vehicle is no longer in an unexpected yaw and driving deviation state, and reaches a safe and stable driving state.

[0088] The current sensor signal includes the current front wheel steering angle signal. It can be understood that the steering angle of the front wheels of the vehicle can be controlled by the steering wheel angle controlled by the driver, and the current front wheel steering angle signal can represent the current steering wheel angle. The expected yaw angular velocity and the expected center of mass sideslip angle can be calculated based on the current front wheel steering angle signal, and the expected yaw angular velocity and the expected center of mass sideslip angle are the expected values ​​of the driver. Expected yaw angular velocity ω ref The calculation formula is as follows:

[0089] ωref =G ω ·δ f (3)

[0090] Among them, G ω is the transfer function of the yaw rate change caused by the front wheel turning angle, δ f is the current front wheel turning angle. According to the linear two-degree-of-freedom (2-DOF) vehicle dynamics model, G ω The expression can be as follows:

[0091]

[0092] Where a is the distance from the center of mass of the vehicle to the front axle of the vehicle, b is the distance from the center of mass of the vehicle to the rear axle of the vehicle; K represents the steering characteristic stability factor of the vehicle, and its expression is:

[0093]

[0094] Among them, m is the vehicle mass, K r and K f Represent the equivalent cornering stiffness of the front and rear wheels of the vehicle respectively.

[0095] Expected sideslip angle β ref The calculation formula can be ref =G β ·δ f Among them, G β is the transfer function of the change in the sideslip angle of the center of mass caused by the front wheel turning angle. In one example, G β =0, therefore, β ref =0.

[0096] Afterwards, the target yaw rate and the target center-of-mass sideslip angle can be determined according to the expected yaw rate and the expected center-of-mass sideslip angle. For example, the expected yaw rate can be used as the target yaw rate, and the expected center-of-mass sideslip angle can be used as the target center-of-mass sideslip angle. Alternatively, the expected yaw rate and the expected center-of-mass sideslip angle can be correlated and the calculated yaw rate and center-of-mass sideslip angle can be used as the target yaw rate and the target center-of-mass sideslip angle.

[0097] See also Figure 2 and Figure 8 In some embodiments, independently controlling a plurality of front wheels and / or a plurality of rear wheels in the vehicle according to a current yaw rate, a current sideslip angle of the center of mass, a target yaw rate, and a target sideslip angle of the center of mass (i.e., 030) includes:

[0098] 031: Calculate the first steering angle and the second steering angle corresponding to the two rear wheels of the vehicle respectively according to the current yaw rate, the current sideslip angle of the center of mass, the target yaw rate and the target sideslip angle of the center of mass;

[0099] 032: Control the steering of the two rear wheels according to the first steering angle and the second steering angle.

[0100] Specifically, the first steering angle and the second steering angle corresponding to the two rear wheels of the vehicle can be calculated according to the current yaw rate, the current center of mass sideslip angle, the target yaw rate and the target center of mass sideslip angle. According to the linear two-degree of freedom (2-DOF) vehicle dynamics model, the target yaw rate and the target center of mass sideslip angle, the vehicle steady-state state equation is as follows:

[0101]

[0102] Among them, x d =[β ref ω ref ] T ;u d =[δ f ]; τ ω and τ β are the inertial link time constants representing the yaw rate and the sideslip angle of the center of mass, respectively.

[0103] In one example, the left rear wheel can be controlled according to the first steering angle, and the right rear wheel can be controlled according to the second steering angle. Let the first steering angle be δ rl , let the second steering angle be δ rr The state equation of the vehicle can be described as:

[0104]

[0105] Where x = [βω r ] T ; u=[δ rl δ rr ] T ;

[0106]

[0107] I z is the vehicle's moment of inertia.

[0108] See also Figure 2 and Fig. 9In some embodiments, the first steering angle and the second steering angle (i.e., 031) corresponding to two rear wheels of the vehicle are calculated according to the current yaw rate, the current center of mass sideslip angle, the target yaw rate, and the target center of mass sideslip angle, including:

[0109] 0311: Determine the first steering angle and the second steering angle corresponding to the two rear wheels of the vehicle according to the current yaw angular velocity, the current center of mass sideslip angle, the target yaw angular velocity and the target center of mass sideslip angle, so as to minimize the tracking error between the current yaw angular velocity and the target yaw angular velocity, and between the current center of mass sideslip angle and the target center of mass sideslip angle.

[0110] Specifically, the classical linear quadratic regulator (LQR) control method is used for control, and the tracking error is defined as:

[0111]

[0112] According to equations (6) and (7), we have:

[0113]

[0114] It can be seen that the problem of controlling the vehicle to minimize the yaw rate when the sideslip angle of the center of mass is zero is to find the optimal solution that minimizes the tracking error. Therefore, equation (9) is an optimal quadratic control problem, and its optimal solution can be described as:

[0115]

[0116] Among them, Q and R are weighted matrices, i.e., LQR controller parameters; Q is a symmetric semi-positive definite matrix with a dimension of 2×2; R is a symmetric positive definite matrix with a dimension of 4×4. The control parameters Q and R can be adjusted based on experience or simulation test results, and remain unchanged after the adjustment process. Therefore, solving equation (10) to obtain u can determine the first steering angle and the second steering angle, so that the steering of the two rear wheels can be controlled according to the first steering angle and the second steering angle. It should be noted that equation (10) can be solved by the Hamiltonian function method or any other solution method, which is not limited here.

[0117] See also Figure 2 and Fig.10 In some embodiments, controlling the steering of the two rear wheels according to the first steering angle and the second steering angle (ie, 032) includes:

[0118] 0321: Determine whether the first steering angle and the second steering angle are within a predetermined angle control range;

[0119] 0322: When the first steering angle and the second steering angle are within a predetermined angle control range, controlling the current steering angles of the two rear wheels according to the first steering angle and the second steering angle;

[0120] 0323: When the first steering angle and the second steering angle are not within the predetermined angle control range, the current steering angles of the two rear wheels are controlled to decrease to zero at a preset rate.

[0121] The predetermined angle control range may be set according to actual conditions. In some embodiments, the predetermined angle control range corresponding to the first steering angle is [-10°, +10°]; and / or the predetermined angle control range corresponding to the second steering angle is [-10°, +10°]. That is to say, the predetermined angle control range corresponding to the first steering angle may be set to [-10°, +10°], and the predetermined angle control range corresponding to the second steering angle may be set to other intervals; or, the predetermined angle control range corresponding to the second steering angle may be set to [-10°, +10°], and the predetermined angle control range corresponding to the first steering angle may be set to other intervals; or, the predetermined angle control range corresponding to the first steering angle and the predetermined angle control range corresponding to the second steering angle may both be set to [-10°, +10°].

[0122] Specifically, first determine whether the first steering angle and the second steering angle are within the predetermined angle control range. When the first steering angle and the second steering angle are within the predetermined angle control range, the angle that the rear wheels need to steer is small. The current steering angles of the two rear wheels are controlled according to the first steering angle and the second steering angle, and the two rear wheels can steer directly. For example, the first steering angle is used to control the steering of the left rear wheel. The current steering angle of the left rear wheel is m°. When the first steering angle is 10° and the predetermined angle control range corresponding to the first steering angle is [-10°, +10°], the first steering angle is within the predetermined angle control range; therefore, the steering motor of the left rear wheel can be controlled to apply a torque to the left rear wheel to control the left rear wheel to turn from m° to 10°.

[0123] When the first steering angle and the second steering angle are not within the predetermined angle control range, the angle that the rear wheels need to steer is relatively large, and the current steering angles of the two rear wheels are directly controlled to decrease to zero at a preset rate, which is equivalent to returning the rear wheels to the straight position. For example, the second steering angle is used to control the steering of the right rear wheel, and the current steering angle of the right rear wheel is m°. When the second steering angle is 30° and the predetermined angle control range corresponding to the second steering angle is [-10°, +10°], the second steering angle is not within the predetermined angle control range; therefore, the steering motor of the right rear wheel can be controlled to apply a torque to the right rear wheel to control the right rear wheel to decrease from m° to zero at a preset rate.

[0124] In this way, the first steering angle and the second steering angle are calculated according to the current yaw angular velocity, the current sideslip angle of the center of mass, the target yaw angular velocity and the target sideslip angle of the center of mass, and the steering of the two rear wheels is controlled by the first steering angle and the second steering angle, so that the current yaw angular velocity and the current sideslip angle of the center of mass of the two rear wheels of the vehicle are close to or equal to the target yaw angular velocity and the target sideslip angle of the center of mass.

[0125] See also Figure 2 and Fig.11 In some embodiments, after controlling the current steering angles of the two rear wheels according to the first steering angle and the second steering angle (ie, 0322), and / or before acquiring the current yaw rate and the current sideslip angle of the center of mass of the vehicle (ie, 010), the vehicle control method further includes:

[0126] 060: Determine whether the vehicle is currently on an unstable road;

[0127] 070: When the vehicle is currently on an unstable road surface, the step of obtaining the current yaw angular velocity and the current sideslip angle of the center of mass of the vehicle is executed.

[0128] Specifically, during the driving process of the vehicle, it can be determined whether the vehicle is currently on an unstable road surface. When it is determined that the vehicle is on an unstable road surface, the above-mentioned steps of obtaining the current yaw rate and the current sideslip angle of the center of mass of the vehicle are performed. When it is determined that the vehicle is not on an unstable road surface, the vehicle moves forward normally. In addition, after controlling the current steering angles of the two rear wheels according to the first steering angle and the second steering angle, it can also be determined whether the vehicle is currently on an unstable road surface. When it is determined that the vehicle is on an unstable road surface, it means that it is still necessary to control the multiple front wheels and / or the multiple rear wheels in the vehicle, and therefore, it is necessary to return to the step of obtaining the current yaw rate and the current sideslip angle of the center of mass of the vehicle. When it is determined that the vehicle is not on an unstable road surface, it means that it is not necessary to control the multiple front wheels and / or the multiple rear wheels in the vehicle, and the control of the multiple front wheels and / or the multiple rear wheels in the vehicle can be terminated.

[0129] It should be noted that whether the vehicle is on an unstable road surface can be determined based on one or more of the current wheel speed, vehicle speed, yaw rate, and road surface visual signals. For example, whether the vehicle is on an unstable road surface can be determined based on the current wheel speed and vehicle speed. When the current wheel speed of the vehicle is equal to the current vehicle speed, it means that the wheels have not produced slippage and rolling, and the vehicle is not on an unstable road surface. When the current wheel speed of the vehicle is greater than the current vehicle speed, it means that the wheels have produced slippage and rolling, and the vehicle is on an unstable road surface. Alternatively, whether the vehicle is on an unstable road surface can be determined based on road surface visual signals. The current road surface can be detected based on computer vision to obtain road surface visual signals. The road surface visual signals can include the current road surface state, the probability of being on an unstable road surface, etc. Of course, a combination of multiple judgment methods can also be used for comprehensive judgment to obtain a more accurate judgment result, which will not be explained one by one here.

[0130] See also Fig.12 The embodiment of the present application also provides a vehicle control device 100, which includes a state estimation module 10 and a calculation control module 20. The state estimation module 10 is used to obtain the current yaw rate and the current center of mass sideslip angle of the vehicle. The calculation control module 20 is used to obtain the target yaw rate and the target center of mass sideslip angle of the vehicle, and independently control the steering of multiple front wheels and / or multiple rear wheels in the vehicle according to the current yaw rate, the current center of mass sideslip angle, the target yaw rate and the target center of mass sideslip angle.

[0131] Please combine Fig.13 The calculation control module 20 may include a central calculation module 21, a first turning angle control module 22 and a second turning angle control module 23. The central calculation module 21 is used to obtain a target yaw rate and a target center of mass sideslip angle of the vehicle. The central calculation module 21, the first turning angle control module 22 and the second turning angle control module 23 are used to independently control the steering of multiple front wheels and / or multiple rear wheels in the vehicle according to the current yaw rate, the current center of mass sideslip angle, the target yaw rate and the target center of mass sideslip angle.

[0132] See also Fig.13 In some embodiments, the vehicle control device 100 further includes a signal acquisition module 30. The signal acquisition module 30 is used to acquire the current sensor signal of the vehicle, wherein the current sensor signal includes the current yaw angular acceleration and the current vehicle speed. At this time, the state estimation module 10 is specifically used to calculate the current yaw angular velocity according to the current yaw angular acceleration; and calculate the current center of mass sideslip angle according to the current vehicle speed.

[0133] In some embodiments, the signal acquisition module 30 is further used to acquire the current sensor signal of the vehicle, wherein the current sensor signal includes the current front wheel steering angle signal. At this time, the calculation control module 20 is specifically used to calculate the expected yaw rate and the expected center of mass sideslip angle according to the current front wheel steering angle signal; and determine the target yaw rate and the target center of mass sideslip angle according to the expected yaw rate and the expected center of mass sideslip angle.

[0134] Among them, the central calculation module 21 of the calculation control module 20 is used to calculate the expected yaw rate and the expected center of mass sideslip angle according to the current front wheel steering angle signal; and determine the target yaw rate and the target center of mass sideslip angle according to the expected yaw rate and the expected center of mass sideslip angle.

[0135] In some embodiments, the calculation control module 20 is specifically used to calculate the first steering angle and the second steering angle corresponding to the two rear wheels in the vehicle according to the current yaw angular velocity, the current sideslip angle of the center of mass, the target yaw angular velocity and the target sideslip angle of the center of mass; and control the steering of the two rear wheels according to the first steering angle and the second steering angle.

[0136] The central calculation module 21 of the calculation control module 20 is used to calculate the first steering angle and the second steering angle corresponding to the two rear wheels of the vehicle according to the current yaw rate, the current center of mass sideslip angle, the target yaw rate and the target center of mass sideslip angle. The first steering angle control module 22 and the second steering angle control module 23 of the calculation control module 20 are used to control the steering of the two rear wheels according to the first steering angle and the second steering angle.

[0137] In some embodiments, the calculation control module 20 is specifically used to determine the first steering angle and the second steering angle corresponding to the two rear wheels of the vehicle respectively according to the current yaw rate, the current center of mass sideslip angle, the target yaw rate and the target center of mass sideslip angle, so as to minimize the tracking error between the current yaw rate and the target yaw rate, and between the current center of mass sideslip angle and the target center of mass sideslip angle. Specifically, it can be performed by the central calculation module 21 of the calculation control module 20.

[0138] In certain embodiments, the computing control module 20 is specifically used to determine whether the first steering angle and the second steering angle are within a predetermined angle control range; when the first steering angle and the second steering angle are within the predetermined angle control range, the current steering angles of the two rear wheels are controlled according to the first steering angle and the second steering angle; when the first steering angle and the second steering angle are not within the predetermined angle control range, the current steering angles of the two rear wheels are controlled to be reduced to zero at a preset rate.

[0139] The central calculation module 21 of the calculation control module 20 is used to determine whether the first steering angle and the second steering angle are within the predetermined angle control range. The first steering angle control module 22 and the second steering angle control module 23 of the calculation control module 20 are used to: when the first steering angle and the second steering angle are within the predetermined angle control range, control the current steering angles of the two rear wheels according to the first steering angle and the second steering angle; when the first steering angle and the second steering angle are not within the predetermined angle control range, control the current steering angles of the two rear wheels to decrease to zero at a preset rate.

[0140] In certain embodiments, after controlling the current steering angle of the two rear wheels according to the first steering angle and the second steering angle, and / or before obtaining the current yaw rate and the current sideslip angle of the center of mass of the vehicle, the calculation control module 20 is further used to determine whether the vehicle is currently on an unstable road surface; when the vehicle is currently on an unstable road surface, the state estimation module 10 is further used to execute the step of obtaining the current yaw rate and the current sideslip angle of the center of mass of the vehicle.

[0141] The central computing module 21 of the computing control module 20 is used to determine whether the vehicle is currently on an unstable road surface.

[0142] It should be pointed out that the explanation of the vehicle control method in the aforementioned embodiment is also applicable to the vehicle control device 100 of the embodiment of the present application, and will not be elaborated here.

[0143] See also Fig.14 The embodiment of the present application also provides a vehicle control system 200, which includes one or more processors 210 and a memory 220. The memory 220 stores a computer program. When the computer program is executed by the processor 210, the vehicle control method of any of the above embodiments is implemented.

[0144] For example, when the computer program is executed by the processor 210, the following vehicle control method is implemented:

[0145] 010: Get the current yaw rate and sideslip angle of the vehicle;

[0146] 020: Get the target yaw rate and target sideslip angle of the vehicle;

[0147] 030: Independently control multiple front wheels and / or multiple rear wheels in the vehicle according to the current yaw rate, the current center of mass sideslip angle, the target yaw rate and the target center of mass sideslip angle.

[0148] For another example, when the computer program is executed by the processor 210, the following vehicle control method is implemented:

[0149] 040: Acquire a current sensor signal of the vehicle, wherein the current sensor signal includes a current yaw angular acceleration and a current vehicle speed;

[0150] At this time, the current yaw rate and the current sideslip angle of the center of mass of the vehicle (ie 010) are obtained, including:

[0151] 011: Calculate the current yaw rate based on the current yaw acceleration;

[0152] 012: Calculate the current sideslip angle of the center of mass based on the current vehicle speed.

[0153] It should be pointed out that the explanations and descriptions of the vehicle control method and the vehicle control device 100 in the aforementioned embodiments are also applicable to the vehicle control system 200 of the embodiments of the present application, and will not be elaborated here.

[0154] See also Fig.15 The embodiment of the present application also provides a computer-readable storage medium 300 on which a computer program 310 is stored, characterized in that when the program is executed by a processor 320, the vehicle control method of any of the above embodiments is implemented.

[0155] For example, when the program is executed by the processor 320, the following vehicle control method is implemented:

[0156] 010: Get the current yaw rate and sideslip angle of the vehicle;

[0157] 020: Get the target yaw rate and target sideslip angle of the vehicle;

[0158] 030: Independently control multiple front wheels and / or multiple rear wheels in the vehicle according to the current yaw rate, the current center of mass sideslip angle, the target yaw rate and the target center of mass sideslip angle.

[0159] For another example, when the program is executed by the processor 320, the following vehicle control method is implemented:

[0160] 040: Acquire a current sensor signal of the vehicle, wherein the current sensor signal includes a current yaw angular acceleration and a current vehicle speed;

[0161] At this time, the current yaw rate and the current sideslip angle of the center of mass of the vehicle (ie 010) are obtained, including:

[0162] 011: Calculate the current yaw rate based on the current yaw acceleration;

[0163] 012: Calculate the current sideslip angle of the center of mass based on the current vehicle speed.

[0164] It should be noted that the explanations and descriptions of the vehicle control method and the vehicle control device 100 in the aforementioned embodiments are also applicable to the computer-readable storage medium 300 in the embodiments of the present application, and will not be elaborated here.

[0165] In summary, the vehicle control method, vehicle control device 100, vehicle control system 200 and computer-readable storage medium 300 of the embodiment of the present application acquire the current yaw rate and current center of mass sideslip angle of the vehicle, as well as the target yaw rate and target center of mass sideslip angle of the vehicle, and independently control multiple front wheels and / or multiple rear wheels according to the current yaw rate, current center of mass sideslip angle, target yaw rate and target center of mass sideslip angle. In this way, the yaw rate and center of mass sideslip angle of the vehicle can be controlled simultaneously, the yaw amplitude and heading angle deviation of the vehicle can be reduced, and the driving stability of the vehicle can be improved.

[0166] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0167] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0168] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable storage medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, a computer-readable storage medium can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples (non-exhaustive list) of computer-readable storage media include the following: an electrical connection with one or more wires (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable storage medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0169] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0170] A person of ordinary skill in the art will appreciate that all or part of the steps carried by the method for implementing the above-mentioned embodiment can be completed by instructing the relevant hardware through a program, and the program can be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment. In addition, each functional unit in each embodiment of the present application can be integrated into a processing module, or each unit can exist physically alone, or two or more units can be integrated into one module. The above-mentioned integrated module can be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. The above-mentioned storage medium can be a read-only memory, a disk or an optical disk, etc.

[0171] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application. The scope of the present application is defined by the claims and their equivalents.

Claims

1. A vehicle control method, characterized in that: include: Obtaining a current yaw rate and a current sideslip angle of the vehicle; Obtaining a target yaw rate and a target center-of-mass sideslip angle of the vehicle; A plurality of front wheels and / or a plurality of rear wheels in the vehicle are independently controlled according to the current yaw rate, the current sideslip angle of the center of mass, the target yaw rate and the target sideslip angle of the center of mass.

2. The vehicle control method according to claim 1, characterized in that: The vehicle control method further includes: Acquiring a current sensor signal of the vehicle, wherein the current sensor signal includes a current yaw angular acceleration and a current vehicle speed; The obtaining of the current yaw rate and the current sideslip angle of the center of mass of the vehicle comprises: Calculating the current yaw angular velocity according to the current yaw angular acceleration; The current center of mass sideslip angle is calculated according to the current vehicle speed.

3. The vehicle control method according to claim 1, characterized in that: The vehicle control method further includes: Acquiring a current sensor signal of the vehicle, wherein the current sensor signal includes a current front wheel steering angle signal; The obtaining of a target yaw rate and a target center-of-mass sideslip angle of the vehicle comprises: Calculating a desired yaw rate and a desired sideslip angle of the center of mass according to the current front wheel steering angle signal; The target yaw rate and the target sideslip angle of the center of mass are determined according to the desired yaw rate and the desired sideslip angle of the center of mass.

4. The vehicle control method according to claim 1, characterized in that: The method of independently controlling a plurality of front wheels and / or a plurality of rear wheels in the vehicle according to the current yaw rate, the current center-of-mass sideslip angle, the target yaw rate, and the target center-of-mass sideslip angle comprises: Calculating a first steering angle and a second steering angle respectively corresponding to two rear wheels of the vehicle according to the current yaw rate, the current sideslip angle of the center of mass, the target yaw rate and the target sideslip angle of the center of mass; The steering of the two rear wheels is controlled according to the first steering angle and the second steering angle.

5. The vehicle control method according to claim 4, characterized in that: The calculating, according to the current yaw rate, the current center-of-mass sideslip angle, the target yaw rate and the target center-of-mass sideslip angle, respectively corresponding to the first steering angle and the second steering angle of the two rear wheels of the vehicle comprises: A first steering angle and a second steering angle respectively corresponding to two rear wheels in the vehicle are determined according to the current yaw angular velocity, the current sideslip angle of the center of mass, the target yaw angular velocity and the target sideslip angle of the center of mass, so as to minimize the tracking error between the current yaw angular velocity and the target yaw angular velocity, and between the current sideslip angle and the target sideslip angle of the center of mass.

6. The vehicle control method according to claim 4, characterized in that: The controlling the steering of the two rear wheels according to the first steering angle and the second steering angle comprises: determining whether the first steering angle and the second steering angle are within a predetermined angle control range; When the first steering angle and the second steering angle are within the predetermined angle control range, controlling the current steering angles of the two rear wheels according to the first steering angle and the second steering angle; When the first steering angle and the second steering angle are not within the predetermined angle control range, the current steering angles of the two rear wheels are controlled to decrease to zero at a preset rate.

7. The vehicle control method according to claim 6, characterized in that: The predetermined angle control range corresponding to the first steering angle is [-10°, +10°]; and / or The predetermined angle control range corresponding to the second steering angle is [-10°, +10°].

8. The vehicle control method according to claim 6, characterized in that: After controlling the current steering angles of the two rear wheels according to the first steering angle and the second steering angle, and / or before acquiring the current yaw rate and the current sideslip angle of the vehicle, the vehicle control method further includes: Determining whether the vehicle is currently on an unstable road surface; When the vehicle is currently on the unstable road surface, the step of obtaining the current yaw rate and the current sideslip angle of the center of mass of the vehicle is performed.

9. The vehicle control method according to claim 8, characterized in that: The unstable road surface includes a split road surface, a butt-jointed road surface, a checkerboard road surface or an icy and snowy slope road surface.

10. A vehicle control device, characterized in that: include: A state estimation module, used to obtain a current yaw rate and a current sideslip angle of the center of mass of the vehicle; A calculation control module is used to obtain a target yaw rate and a target sideslip angle of the center of mass of the vehicle, and independently control a plurality of front wheels and / or a plurality of rear wheels in the vehicle according to the current yaw rate, the current sideslip angle of the center of mass, the target yaw rate and the target sideslip angle of the center of mass.

11. A vehicle control system, characterized in that: The vehicle control system includes one or more processors and a memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, the vehicle control method according to any one of claims 1 to 9 is implemented.

12. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the vehicle control method described in any one of claims 1 to 9 is implemented.

Images