Methods, devices, equipment and storage media for controlling tire force distribution

Abstract

This application provides a tire force distribution control method, device, equipment, and storage medium, relating to the field of vehicle technology. The method includes determining the vehicle's desired force matrix based on acquired vehicle driving state information and road centerline position information; optimizing the tire force distribution based on the desired force matrix, tire force constraints, and a pseudo-inverse matrix with adaptive parameter function, while ensuring that the error between the distributed tire force matrix and the desired force matrix is ​​minimized; and controlling the vehicle's wheel angle and driving torque based on the distributed tire force matrix. This application can perform optimization solutions based on dynamic operating conditions, providing highly timely and accurate calculation results, avoiding safety hazards caused by slow tire force distribution speed and large tire force distribution errors under extreme operating conditions.

Description

Technical Field

[0001] This application belongs to the field of automotive control technology, specifically relating to a tire force distribution control method, device, equipment, and storage medium. Background Technology

[0002] With the rapid advancement of technology, various technologies in the automotive field, such as manufacturing and control technologies, are constantly developing, including the emergence of intelligent vehicles. Currently, most intelligent vehicle control systems adopt a hierarchical control framework, including path tracking, tire force distribution, and execution control. Among these, fully drive-by-wire intelligent electric vehicles can independently control the steering angle and torque of each wheel, utilizing redundant steering, driving, and braking capabilities to achieve special maneuvers, such as turning on the spot and lateral movement. Tire force distribution, in particular, requires distributing the desired total force and torque of the vehicle's motion, given by path tracking, to each wheel.

[0003] During the distribution of tire forces in a vehicle, it is necessary to optimize the distribution results to minimize the error between the resultant force of each tire and the desired total force, thus ensuring vehicle stability. Furthermore, it is also necessary to optimize the calculation methods to simplify the computation and ensure the real-time performance of the calculation process and results. Current methods for tire force distribution include using controller reconfiguration to ensure the vehicle tracks the path under extreme conditions and using nonlinear programming methods for tire force distribution. However, these methods are computationally complex and therefore difficult to meet real-time requirements. Other methods include using the Lagrange method to calculate the target longitudinal force of each tire and to avoid longitudinal slippage while meeting yaw moment requirements to ensure vehicle yaw and roll stability. However, these methods do not consider the operational requirements under extreme conditions and therefore also fail to meet stability requirements.

[0004] The aforementioned vehicle tire force distribution methods have the following problems: due to the high computational difficulty, they cannot meet the real-time requirements of the calculation process and results; and because they do not consider the situation where tires cannot adapt to parameters under extreme conditions such as tire slippage, they cannot guarantee vehicle stability. Currently, no effective solutions have been proposed. Summary of the Invention

[0005] This application provides a tire force distribution control method, device, and storage medium to solve the problems that existing vehicle tire force distribution methods cannot meet real-time requirements and cannot guarantee vehicle stability.

[0006] In a first aspect, this application provides a method for controlling tire force distribution, including:

[0007] Obtain vehicle driving status information and the centerline position information of the target road;

[0008] Based on the vehicle driving status information and the centerline position information, determine the vehicle's expected force matrix.

[0009] Based on the vehicle desired force matrix, tire force constraints, and pseudo-inverse matrix, tire force is allocated, ensuring that the vehicle force allocation matrix corresponding to the allocated tire force has the smallest error with the vehicle desired force matrix. The pseudo-inverse matrix is ​​a pseudo-inverse matrix implemented based on the tire force weight matrix.

[0010] The wheel angle and driving torque of the vehicle are controlled according to the allocated tire force matrix.

[0011] In one possible design, the tire force constraint conditions include:

[0012] When the rear wheels of the vehicle cannot actively steer, the turning angle of the left and right wheels is 0°, and the tire force of the rear wheels is determined according to the sideslip angle of the vehicle's center of gravity.

[0013] When both the front and rear wheels of a vehicle can steer, the rate of change of the steering angle of the left and right wheels is the same, and the steering angle of the left wheel is equal to that of the right wheel. The tire force constraint condition is achieved through the following formula:

[0014]

[0015]

[0016] The optimal F matrix can be solved using the following formula:

[0017]

[0018] in,

[0019] F = [f x11 f x12 f x21 f x22 f y11 f y12 f y21 f y22 ] T

[0020]

[0021] a ij =cosδ ij ;c ij =(-1) j dcosδ ij +(-1) i+1 l i cosδ ij ;

[0022] b ij=sinδ ij ;d ij =(-1) j+1 dsinδ ij +(-1) i+1 l i cosδ ij

[0023] Where, δ ij For each wheel's turning angle, C f For lateral stiffness, l f d represents the longitudinal velocity, lateral velocity, yaw rate, front wheelbase, and track width, respectively; fxij represents the longitudinal force, and fyij represents the lateral force.

[0024] V is the desired force matrix of the vehicle, and F is the force distribution matrix of the vehicle. x For the longitudinal resultant force, F y For the resultant force in the lateral direction, M z The resultant torque is in the direction of rotation.

[0025] In one possible design, the pseudo-inverse matrix is ​​implemented using the following formula:

[0026] min J=||W(uu d )||

[0027] stv d =Nu

[0028] Where, min J is the minimum error parameter that satisfies the vehicle force distribution matrix and the vehicle desired force matrix, u is the control variable, and u is equal to the vehicle force distribution matrix F. d v is the desired control variable. d For the desired control command, the v d At this point, it equals the vehicle's desired force matrix V; stvd refers to calculating the control quantity u under the condition of satisfying the desired control command, and performing a pseudo-inverse solution with the minimum error between the vehicle's force distribution matrix and the vehicle's desired force matrix. The control quantity u is:

[0029]

[0030] Where # represents the solution for the pseudo-inverse matrix, and N # Represents the pseudo-inverse matrix of N;

[0031] The matrix W is adaptively adjusted using the following formula:

[0032]

[0033] in,

[0034]

[0035] Among them, F z11 F z12 F z21 F z2 These represent the vertical loads on the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. The W... X The W y This is the tire force weight matrix.

[0036] In one possible design, given the physical constraints of a front-wheel steering vehicle, when the rear wheels cannot actively steer and the left and right rear wheel steering angles are 0°,

[0037] The extended matrices of the vehicle's expected force matrix V and matrix N are reconstructed using the following formulas:

[0038]

[0039]

[0040] in, The extended matrix reconstructed from the vehicle's desired force matrix V. δ is an extension matrix of matrix N; ij For each wheel's turning angle, C f For lateral stiffness, l f d represents longitudinal velocity, lateral velocity, yaw rate, front wheelbase, track width, and f, respectively. xij For longitudinal force, f yij It is a lateral force;

[0041] The control quantity of the weighted pseudo-inverse matrix algorithm is implemented through the following formula:

[0042]

[0043] u = F d =[f x11 f x12 f x21 f x22 f y11 f y12 f y21 f y22 ] T ;

[0044] Among them, f xij For longitudinal force, f yij Let u be the lateral force, and u be the control variable, where u is equal to the vehicle force distribution matrix F. d v is the desired control variable. d For the desired control command, the v dAt this point, it equals the vehicle's expected force matrix V.

[0045] In one possible design, if the tire force constraint conditions cannot be met, the tire lateral force is replaced with a corrected lateral force, and the tire longitudinal force is replaced with a corrected longitudinal force, achieved through the following formula:

[0046]

[0047]

[0048] in, These represent the corrected longitudinal and lateral forces, respectively, where μ is the road friction coefficient, and F... zij It is a vertical force.

[0049] In one possible design, controlling the vehicle's wheel angle and driving torque based on the allocated tire force matrix is ​​achieved through the following formula:

[0050]

[0051]

[0052] Where, δ ij For each wheel's turning angle, C f For lateral stiffness, l f d represents longitudinal velocity, lateral velocity, yaw rate, front wheelbase, track width, and T, respectively. ij For driving torque, I w Let ω be the moment of inertia of the tire. ij r is the wheel speed. tire f is the rolling radius of the wheel. roll This refers to the rolling resistance of the wheel.

[0053] Secondly, this application provides a tire force distribution device, comprising:

[0054] The acquisition module is used to acquire vehicle driving status information and the centerline position information of the target road;

[0055] The first processing module is used to determine the vehicle's expected force matrix based on the vehicle driving status information and the centerline position information.

[0056] The second processing module is used to perform tire force allocation based on the vehicle desired force matrix, tire force constraint conditions and pseudo-inverse matrix, and to ensure that the vehicle allocated torque corresponding to the allocated tire force matrix has the smallest error with the vehicle desired torque, wherein the pseudo-inverse matrix is ​​a pseudo-inverse matrix implemented based on the tire force weight matrix;

[0057] An execution module is used to control the wheel angle and driving torque of the vehicle according to the allocated tire force matrix.

[0058] Thirdly, this application provides a tire force distribution device, including: a processor, and a memory communicatively connected to the processor;

[0059] The memory stores computer-executed instructions;

[0060] The processor executes computer execution instructions stored in the memory to implement a method for controlling tire force.

[0061] Fourthly, this application provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement a tire force distribution control method.

[0062] Fifthly, this application provides a program product, wherein the computer program, when executed by a processor, implements a method for controlling tire force.

[0063] This application provides a tire force distribution control method, device, equipment, and storage medium. The method determines the vehicle's desired force matrix based on acquired vehicle driving state information and road centerline position information. Then, based on the vehicle's desired force matrix, tire force constraints, and a pseudo-inverse matrix with parameter adaptive function, it optimizes the distribution of the vehicle's tire forces, ensuring that the error between the distributed tire force matrix and the vehicle's desired force matrix is ​​minimized. The method controls the vehicle's wheel angle and driving torque based on the distributed tire force matrix. It can optimize solutions based on dynamic operating conditions, providing high real-time and high-precision calculation results, avoiding safety hazards caused by slow tire force distribution speed and large tire force distribution errors under extreme operating conditions. Attached Figure Description

[0064] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0065] Figure 1 This is a system schematic diagram of the tire force distribution control method provided in the embodiments of this application;

[0066] Figure 2 A schematic flowchart of the tire force distribution control method provided in the embodiments of this application. Figure 1 ;

[0067] Figure 3A schematic flowchart of the tire force distribution control method provided in the embodiments of this application. Figure 2 ;

[0068] Figure 4 This is a schematic diagram of vehicle tire forces provided in an embodiment of this application;

[0069] Figure 5 This is a schematic diagram of the tire force distribution device provided in the embodiments of this application;

[0070] Figure 6 This is a schematic diagram of the tire force distribution device provided in an embodiment of this application. Detailed Implementation

[0071] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0072] The terms "first," "second," "third," "fourth," etc., used in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented, for example, in orders other than those illustrated or described herein.

[0073] With the rapid advancement of technology, various technologies in the automotive field, such as manufacturing and control technologies, are also constantly developing. Among them, the control systems of intelligent vehicles mostly adopt a hierarchical control framework, including path tracking, tire force distribution, and execution control. Tire force distribution, in particular, involves distributing the expected total force of vehicle motion, given by path tracking, to each wheel.

[0074] In the process of distributing tire forces in a vehicle, it is necessary to optimize the distribution results to minimize the error between the resultant force of each tire and the desired total force, thereby ensuring vehicle stability. Furthermore, it is also necessary to optimize the calculation method to simplify the computational complexity and ensure the real-time nature of the calculation process and results. However, current methods for tire force distribution suffer from limitations due to their high computational complexity, which prevents them from meeting the real-time requirements of the calculation process and results. Additionally, because they do not consider extreme tire conditions such as tire slippage, they also fail to guarantee vehicle stability. Therefore, a more efficient and real-time-sensitive method for distributing and controlling tire forces is needed.

[0075] This application provides a tire force distribution control method. Based on the acquired vehicle driving state information and road centerline position information, the desired vehicle force matrix is ​​determined. Then, based on the desired vehicle force matrix, tire force constraints, and a pseudo-inverse matrix with parameter adaptive function, the tire force of the vehicle is optimized and distributed. At the same time, it is ensured that the error between the distributed tire force matrix and the desired vehicle force matrix is ​​minimized. The wheel angle and driving torque of the vehicle are controlled according to the distributed tire force matrix. It can optimize the solution according to dynamic working conditions, and obtain high real-time and high-precision calculation results, avoiding safety hazards caused by slow tire force distribution speed and large tire force distribution error under extreme working conditions.

[0076] Figure 1 A system schematic diagram of a tire force distribution control method provided in an embodiment of this application is shown below. Figure 1 As shown, it includes an environmental perception unit 101, a path tracking unit 102, a tire force distribution unit 103, an execution control unit 104, and an actuator 105.

[0077] The environmental perception unit 101 transmits the acquired vehicle driving status information and road centerline position information to the path tracking unit 102. The path tracking unit 102 determines the total force and total torque data of the vehicle based on the acquired vehicle driving status information and road centerline position information, and transmits the determined total force and total torque data to the tire force distribution unit 103. The tire force distribution unit 103 optimizes the distribution of the vehicle's tire force based on the obtained total force and total torque data, and transmits the optimized tire force data to the control unit 104. The control unit 104 sends a control signal to the actuator 105 based on the distributed tire force data to achieve the desired tire force.

[0078] The technical solutions of this application and how they solve the aforementioned technical problems are described in detail below using specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0079] Example 1

[0080] Figure 2 A schematic flowchart of the tire force distribution control method provided in the embodiments of this application. Figure 1 .like Figure 2 As shown, the execution subject in this embodiment can be, for example, a... Figure 1 The method includes: (The text appears to be incomplete and contains several grammatical errors. A more accurate translation would require the full context.)

[0081] S201. Obtain vehicle driving status information and centerline position information of the target road;

[0082] Among them, vehicle driving status information refers to information obtained through sensors, including the vehicle's absolute coordinates, speed, yaw angle, etc.; target road refers to the predicted road that the vehicle will travel on in the future; and the centerline position information of the target road refers to the absolute coordinate information of the lane center.

[0083] Specifically, the system obtains vehicle driving status information, including the absolute coordinates, speed, and yaw angle of the controlled vehicle, through sensors, and then predicts the absolute coordinates of the lane center of the controlled vehicle to adapt to its movement.

[0084] S202. Determine the vehicle's expected force matrix based on the vehicle's driving status information and centerline position information.

[0085] Specifically, after receiving the vehicle driving status information and the centerline position information from the environmental perception unit, the path tracking unit determines the vehicle's expected force matrix based on the path tracking error. This expected force matrix includes, for example, data on lateral force, longitudinal force, yaw moment, and total force and total moment.

[0086] The path tracking unit can employ methods such as model predictive control, PID control (Proportional Integral Derivative, PID), and LQR control (linear quadratic regulator, LQR). PID control refers to a control system that controls the error generated by comparing the real-time data of the controlled object with the given value using the proportional, integral, and derivative methods. Based on the target road centerline position obtained by the environmental perception unit and the actual position of the vehicle, the expected total force and torque of the vehicle's motion are obtained.

[0087] S203. Based on the vehicle desired force matrix, tire force constraints and pseudo-inverse matrix, perform tire force allocation, and ensure that the error between the vehicle allocation force matrix corresponding to the allocated tire force and the vehicle desired force matrix is ​​minimized, wherein the pseudo-inverse matrix is ​​a pseudo-inverse matrix implemented based on the tire force weight matrix.

[0088] Among them, tire force constraint conditions refer to the restrictions on vehicle movement based on the vehicle's design structure during vehicle operation, including situations where the rear wheels of the vehicle cannot actively steer and situations where both the front and rear wheels of the vehicle can steer.

[0089] The pseudo-inverse matrix refers to the force distributed to each wheel's tires by calculating the vehicle force distribution matrix based on the obtained vehicle desired force matrix under the condition of satisfying tire force constraints.

[0090] Specifically, based on the obtained vehicle desired force matrix and tire force constraints, the optimal tire force distribution result can be obtained by calculating the pseudo-inverse matrix. Furthermore, the pseudo-inverse matrix also includes a parameter adaptive weight matrix, namely the tire force weight matrix. By varying the load on each wheel, the distribution of vehicle tire forces can be further optimized. At the same time, the parameter adaptive weight matrix ensures that the error between the vehicle force distribution matrix corresponding to the distributed tire forces and the vehicle desired force matrix is ​​minimized. Therefore, compared with ordinary pseudo-inverse matrices, the pseudo-inverse matrix in this application can automatically adjust the distribution target through the parameter adaptive weight matrix, resulting in less computation.

[0091] S204. Control the wheel angle and driving torque of the vehicle according to the allocated tire force;

[0092] Among them, wheel angle refers to the angle formed between the direction the tires point and the direction the vehicle is facing when the car is turning, and driving torque refers to the physical quantity that the driving force of the vehicle produces a rotational effect on the tires.

[0093] Specifically, after the control unit receives the data from the optimized tire force matrix, it sends control signals to the actuators based on the data in the optimized tire force matrix. The control signals include the vehicle's wheel angle data and driving torque data to achieve the desired tire force.

[0094] This application provides a tire force distribution control method. By acquiring vehicle driving state information and road centerline position information, the desired vehicle force matrix is ​​determined. Based on the desired vehicle force matrix, tire force constraints, and a pseudo-inverse matrix, the tire force of the vehicle is optimally distributed, ensuring that the error between the distributed tire force matrix and the desired vehicle force matrix is ​​minimized. The pseudo-inverse matrix is ​​a pseudo-inverse matrix implemented based on the tire force weight matrix. The wheel angle and driving torque of the vehicle are controlled based on the distributed tire force matrix, achieving high real-time and high-precision tire force distribution control and avoiding safety hazards caused by large tire force distribution errors.

[0095] The following specific embodiment will be used to describe in detail the tire force distribution control method of this application.

[0096] Example 2

[0097] Figure 3 A schematic flowchart of the tire force distribution control method provided in the embodiments of this application. Figure 2 . Figure 4 This is a schematic diagram of vehicle tire forces provided for an embodiment of this application. (In conjunction with...) Figure 3 and Figure 4 The method is described in detail below, and includes:

[0098] S301. Obtain vehicle driving status information and centerline position information of the target road;

[0099] Specifically, the environmental perception unit obtains information about the driving status of the controlled moving vehicle through sensors, including absolute coordinates, speed, yaw angle, and lane center absolute coordinates that are adapted to the movement of the moving vehicle.

[0100] S302. Determine the vehicle's expected force matrix based on the vehicle's driving status information and centerline position information.

[0101] Specifically, after receiving the vehicle driving status information and the centerline position information from the environmental perception unit, the path tracking unit determines the expected force matrix data, including lateral force, longitudinal force, yaw moment, and total force and total moment data, based on the path tracking error.

[0102] S303. Determine the tire force constraint conditions, including the situation when the rear wheels of the vehicle cannot actively steer and the situation when both the front and rear wheels of the vehicle can steer.

[0103] In the case where both the front and rear wheels of the vehicle can steer, and the rates of change of the steering angles of the left and right wheels are the same, with the left wheel steering angle equal to the right wheel steering angle, the tire force constraint condition can be expressed by the following formula:

[0104]

[0105]

[0106] Based on the tire force constraint condition that both the front and rear wheels of the vehicle can steer, the optimal vehicle force distribution matrix F is solved using the following formula:

[0107]

[0108] in,

[0109] F = [f x11 f x12 f x21 f x22 f y11f y12 f y21 f y22 ] T

[0110]

[0111] a ij =cosδ ij ;c ij =(-1) j dcosδ ij +(-1) i+1 l i cosδ ij ;

[0112] b ij =sinδ ij ;d ij =(-1) j+1 dsinδ ij +(-1) i+1 l i cosδ ij

[0113] Combination Figure 4 As shown, where δ ij For each wheel's turning angle, C f For lateral stiffness, l f d represents longitudinal velocity, lateral velocity, yaw rate, front wheelbase, track width, and f, respectively. xij For longitudinal force, f yij V is the lateral force; F is the desired force matrix of the vehicle; and F is the force distribution matrix of the vehicle. x For the longitudinal resultant force, F y For the resultant force in the lateral direction, M z The resultant torque is in the direction of rotation;

[0114] Specifically, the longitudinal resultant force F contained in the known vehicle desired force matrix V. x lateral resultant force F y and the resultant torque M in the direction of rotation Z And the known wheel rotation angle δ ij The N matrix formed can be used to initially calculate the vehicle force distribution matrix F.

[0115] Specifically, when the rear wheels of the vehicle cannot actively steer and the turning angle of the left and right wheels is 0°, the extended matrices of the vehicle's desired force matrix V and N are reconstructed using the following formula:

[0116]

[0117]

[0118] in, This is an extended matrix reconstructed from the vehicle's desired torque matrix V. δ is an extension matrix of matrix N; ij For each wheel's turning angle, C f For lateral stiffness, l f d represents the longitudinal velocity, lateral velocity, yaw rate, front wheelbase, and track width, respectively.

[0119] S304. When the vehicle cannot meet the tire force constraint conditions, the tire lateral force is replaced with a corrected lateral force, and the tire longitudinal force is replaced with a corrected longitudinal force, which is achieved through the following formula:

[0120]

[0121]

[0122] Combination Figure 4 As shown, where f xij For longitudinal force, f yij It is a lateral force. These represent the corrected longitudinal and lateral forces, respectively, where μ is the road friction coefficient, and F... zij It is a vertical force.

[0123] S305. Tire force distribution is achieved through a pseudo-inverse matrix;

[0124] Specifically, based on the vehicle's desired torque matrix and tire force constraints, and while ensuring that the error between the vehicle's allocated torque matrix corresponding to the allocated tire force and the vehicle's desired torque matrix is ​​minimized, tire force allocation is achieved through a pseudo-inverse matrix with a tire force weight matrix.

[0125] In the case where both the front and rear wheels of the vehicle can steer, the pseudo-inverse matrix is ​​implemented using the following formula:

[0126] min J=||W(uu d )||

[0127] stv d =Nu

[0128] Where W is the parameter adaptive matrix, min J is the minimum error parameter that satisfies the vehicle force distribution matrix and the vehicle desired force matrix, to ensure that the error between the vehicle force distribution torque matrix corresponding to the distributed tire force and the vehicle desired torque matrix is ​​minimized, and u is the control variable, where u is equal to the vehicle force distribution matrix F. d v is the desired control variable. dFor the desired control command, the v d At this point, it equals the vehicle's expected force matrix V; stv d This refers to finding the control quantity u under the desired control command, using a pseudo-inverse solution with the objective of minimizing the error between the vehicle force distribution matrix and the vehicle desired force matrix. The control quantity u is:

[0129]

[0130] Where # represents the solution for the pseudo-inverse matrix, and N # Let N be the pseudo-inverse matrix. In this case, the control quantity u is equal to the vehicle force distribution matrix F. The matrix W is adaptively adjusted using the following formula:

[0131]

[0132] in,

[0133]

[0134] Combination Figure 4 As shown, F z11 ,F z12 ,F z21 ,F z22 These represent the vertical loads on the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. The W... X The W y This is the tire force weight matrix.

[0135] When the rear wheels of a vehicle cannot actively steer, the pseudo-inverse matrix is ​​achieved using the following formula:

[0136]

[0137] u = F d =[f x11 f x12 f x21 f x22 f y11 f y12 f y21 f y22 ] T ;

[0138] Among them, f xij For longitudinal force, f yij Let u be the lateral force and 'u' be the control variable. In this case, the control variable u is equal to the vehicle force distribution matrix F. d v is the desired control variable. d For the desired control command, the v d At this point, it equals the vehicle's expected force matrix V.

[0139] S306. Based on the allocated tire force matrix, control the vehicle's wheel angle and driving torque to achieve tire force distribution:

[0140] Specifically, after receiving the optimized tire force matrix data, the control unit sends control signals to the actuators based on the allocated tire force matrix data. These control signals include the vehicle's wheel angle data and driving torque data, and the desired tire force is achieved using the following formula:

[0141]

[0142]

[0143] Where, δ ij For each wheel's turning angle, C f For lateral stiffness, l f d represents longitudinal velocity, lateral velocity, yaw rate, front wheelbase, track width, and T, respectively. ij For driving torque, I w Let ω be the moment of inertia of the tire. ij r is the wheel speed. tire f is the rolling radius of the wheel. roll f is the rolling resistance of the wheel. xij For longitudinal force, f yij For lateral force, F zij It is a vertical force.

[0144] This application provides a tire force distribution control method. Based on acquired vehicle driving state information and road centerline position information, a desired vehicle force matrix is ​​determined. The tire force is then optimized and distributed according to the desired force matrix, tire force constraints, and a pseudo-inverse matrix. The tire force constraints include three scenarios: when the rear wheels cannot actively steer, when both front and rear wheels can steer, and when the vehicle cannot meet the tire force constraints. The method ensures that the error between the distributed tire force matrix and the desired vehicle force matrix is ​​minimized. The pseudo-inverse matrix is ​​a pseudo-inverse matrix implemented based on the tire force weight matrix, which has an adaptive function based on load parameters. The method controls the vehicle's wheel angle and driving torque based on the distributed tire force matrix, achieving high real-time and high-precision tire force distribution control. This avoids safety hazards caused by slow tire force distribution speed and large tire force distribution errors under extreme conditions such as wheel slippage.

[0145] In this embodiment of the invention, electronic devices or main control devices can be divided into functional modules according to the above method examples. For example, each function can be divided into its own functional modules, or two or more functions can be integrated into one processing unit. The integrated unit can be implemented in hardware or as a software functional module. It should be noted that the module division in this embodiment of the invention is illustrative and only represents one logical functional division; other division methods may be used in actual implementation.

[0146] Figure 5 This is a schematic diagram of the tire force distribution device provided in an embodiment of this application. Figure 5 As shown, the device 500 includes:

[0147] The acquisition module 501 is used to acquire vehicle driving status information and centerline position information of the target road;

[0148] The first processing module 502 is used to determine the vehicle's expected force matrix based on the vehicle's driving status information and centerline position information.

[0149] The second processing module 503 is used to perform tire force allocation based on the vehicle desired force matrix, tire force constraint conditions and pseudo-inverse matrix, and to ensure that the error between the vehicle allocated torque corresponding to the allocated tire force matrix and the vehicle desired torque is minimized. The pseudo-inverse matrix is ​​a pseudo-inverse matrix implemented based on the tire force weight matrix.

[0150] The execution module 504 is used to control the wheel angle and driving torque of the vehicle according to the allocated tire force matrix.

[0151] Furthermore, the second processing module 503 is specifically used for: when the rear wheels of the vehicle cannot actively steer, the turning angle of the left and right wheels is 0°, and at this time the tire force of the rear wheels is determined according to the sideslip angle of the vehicle's center of gravity; when both the front and rear wheels of the vehicle can steer, the rate of change of the turning angle of the left and right wheels is the same, and the turning angle of the left wheel is equal to the turning angle of the right wheel. The tire force constraint condition is achieved through the following formula:

[0152]

[0153]

[0154] The optimal F matrix can be solved using the following formula:

[0155]

[0156] in,

[0157] F = [f x11 f x12 f x21 fx22 f y11 f y12 f y21 f y22 ] T

[0158]

[0159] a ij =cosδ ij ;c ij =(-1) j dcosδ ij +(-1) i+1 l i cosδ ij ;

[0160] b ij =sinδ ij ;d ij =(-1) j+1 dsinδ ij +(-1) i+1 l i cosδ ij

[0161] Where, δ ij For each wheel's turning angle, C f For lateral stiffness, l f d represents longitudinal velocity, lateral velocity, yaw rate, front wheelbase, track width, and f, respectively. xij For longitudinal force, f yij V is the lateral force; F is the desired force matrix of the vehicle; and F is the force distribution matrix of the vehicle. x For the longitudinal resultant force, F y For the resultant force in the lateral direction, M z The resultant torque is in the direction of rotation.

[0162] Furthermore, the second processing module 503 is specifically used for: implementing the pseudo-inverse matrix using the following formula:

[0163] min J=||W(uu d )||

[0164] stv d =Nu

[0165] Where, min J is the minimum error parameter that satisfies the vehicle force distribution matrix and the vehicle desired force matrix, u is the control variable, and u is equal to the vehicle force distribution matrix F. d v is the desired control variable. d For the desired control command, the v dAt this point, it equals the vehicle's expected force matrix V; stv d Under the condition of satisfying the desired control command, the control quantity u is calculated by performing a pseudo-inverse solution with the minimum error between the vehicle force distribution matrix and the vehicle desired torque. The control quantity u is:

[0166]

[0167] Where # represents the solution for the pseudo-inverse matrix, and N # Represents the pseudo-inverse matrix of N;

[0168] The matrix W is adaptively adjusted using the following formula:

[0169]

[0170] in,

[0171]

[0172] Among them, F z11 ,F z12 ,F z21 ,F z22 These represent the vertical loads on the left front wheel, right front wheel, left rear wheel, and right rear wheel, respectively. The W... X The W y This is the tire force weight matrix.

[0173] Furthermore, the second processing module 503 is specifically used for: under the physical constraints of front-wheel steering, when the rear wheels of the vehicle cannot actively steer and the left and right rear wheel turning angles are 0°, reconstructing the extended matrices of the vehicle's desired force matrix V and N matrix, achieved through the following formula:

[0174]

[0175]

[0176] in, The extended matrix reconstructed from the vehicle's desired force matrix V. Let δ be an extension matrix of N; where δ ij For each wheel's turning angle, C f For lateral stiffness, l f d represents longitudinal velocity, lateral velocity, yaw rate, front wheelbase, track width, and f, respectively. xij For longitudinal force, f yij It is a lateral force;

[0177] The control quantity of the weighted pseudo-inverse matrix algorithm is implemented through the following formula:

[0178]

[0179] u = F d =[f x11 f x12 f x21 f x22 f y11 f y12 f y21 f y22 ] T ;

[0180] Among them, f xij For longitudinal force, f yij Let u be the lateral force, and u be the control variable, where u is equal to the vehicle force distribution matrix F. d v is the desired control variable. d For the desired control command, the v d At this point, it equals the vehicle's expected force matrix V.

[0181] Furthermore, the second processing module 503 is specifically used to: replace the tire lateral force with a corrected lateral force and the tire longitudinal force with a corrected longitudinal force when the tire force constraint conditions cannot be met, through the following formula:

[0182]

[0183]

[0184] in, These represent the corrected longitudinal and lateral forces, respectively, where μ is the road friction coefficient, and F... zij It is a vertical force.

[0185] Furthermore, the execution module 504 is specifically used to: control the wheel angle and driving torque of the vehicle according to the allocated tire force matrix using the following formula:

[0186]

[0187]

[0188] Where, δ ij For each wheel's turning angle, C f For lateral stiffness, l f d represents longitudinal velocity, lateral velocity, yaw rate, front wheelbase, track width, and T, respectively. ij For driving torque, I w Let ω be the moment of inertia of the tire. ij r is the wheel speed. tire f is the rolling radius of the wheel. roll This refers to the rolling resistance of the wheel.

[0189] The tire force distribution device provided in this embodiment can execute a tire force distribution control method of the above embodiment. Its implementation principle and technical effect are similar, and will not be described again here.

[0190] In the specific implementation of the aforementioned tire force distribution control method, each module can be implemented as a processor. The processor can execute computer execution instructions stored in the memory, so that the processor executes the aforementioned gear control method based on heavy-duty vehicles.

[0191] Figure 6 This is a schematic diagram of the tire force distribution device provided in an embodiment of this application. Figure 6 As shown, the electronic device 600 includes at least one processor 601 and a memory 602. The electronic device 600 also includes a communication component 603. The processor 601, memory 602, and communication component 603 are connected via a bus 604.

[0192] In a specific implementation, at least one processor 601 executes computer execution instructions stored in the memory 602, causing at least one processor 601 to execute a tire force distribution control method as executed on the electronic device side.

[0193] The specific implementation process of processor 601 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0194] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0195] The memory may include high-speed RAM, and may also include non-volatile storage (NVM), such as at least one disk storage.

[0196] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0197] The above description of the functions implemented by electronic devices and main control devices has introduced the solutions provided by the embodiments of the present invention. It is understood that, in order to implement the above functions, the electronic device or main control device includes hardware structures and / or software modules corresponding to the execution of each function. By combining the units and algorithm steps of the various examples described in the embodiments of the present invention, the embodiments of the present invention can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed by hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the technical solutions of the embodiments of the present invention.

[0198] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the above-described tire force distribution control method.

[0199] The aforementioned computer-readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0200] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an Application Specific Integrated Circuit (ASIC). Alternatively, the processor and the readable storage medium can exist as discrete components in an electronic device or a host device.

[0201] This application also provides a computer program product, comprising: a computer program stored in a readable storage medium, wherein at least one processor of an electronic device can read the computer program from the readable storage medium, and the at least one processor executes the computer program to cause the electronic device to perform the scheme provided in any of the above embodiments.

[0202] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0203] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A control method of tire force distribution applied to a vehicle, characterized by, The method comprises: acquiring vehicle driving state information and center line position information of a target road; determining a vehicle expected force matrix of vehicle driving according to the vehicle driving state information and the center line position information; performing tire force distribution according to the vehicle expected force matrix, tire force constraint conditions and a pseudo-inverse matrix, and ensuring that a vehicle distribution force matrix corresponding to the distributed tire force matrix is minimum in error with the vehicle expected force matrix, wherein the pseudo-inverse matrix is a pseudo-inverse matrix realized based on a tire force weight matrix; controlling wheel steering angles and driving torques of the vehicle according to the distributed tire force matrix.

2. The method of claim 1, wherein, The tire force constraint conditions comprise: when rear wheels of the vehicle cannot actively steer, left and right wheel steering angles are 0°, and rear wheel tire forces are determined according to a center of mass side slip angle of the vehicle; when front and rear wheels of the vehicle can steer, a left wheel steering angle change rate is the same as a right wheel steering angle change rate, and the left wheel steering angle is equal to the right wheel steering angle, and the tire force constraint conditions are realized through the following formula: an optimal F matrix is solved through the following formula: wherein, wherein, is the individual wheel angle, is the cornering stiffness, are the longitudinal velocity, lateral velocity, yaw rate, front wheel track, wheel base, is the longitudinal force, is the lateral force; wherein, is a left front wheel steering angle, is a right front wheel steering angle, is a left rear wheel steering angle, is a right rear wheel steering angle; wherein, is the left front wheel longitudinal force, is the right front wheel longitudinal force, is the left rear wheel longitudinal force, is the right rear wheel longitudinal force; is the left front wheel lateral force, is the right front wheel lateral force, is the left rear wheel lateral force, is the right rear wheel lateral force; and NF is a vehicle desired force matrix, assigning a force matrix to the vehicle, N is a tire force distribution matrix, is a longitudinal resultant force, is a lateral resultant force, is a rotational direction resultant moment.

3. The method of claim 2, wherein, the pseudo-inverse matrix is realized through the following formula: Wherein, min J is the minimum error parameter meeting the vehicle distribution matrix and the vehicle expected matrix, is the control variable, and the vehicle distribution matrix , is the expected control variable, is the expected control instruction, and the vehicle expected matrix ; is the control variable meeting the expected control instruction, is the pseudo-inverse solution of the error between the vehicle distribution matrix and the vehicle expected matrix, and the control variable is: where # is the pseudo-inverse matrix solution, denotes the pseudo-inverse matrix of N; The matrix The adaptive adjustment is made by the following equation: wherein, wherein, respectively represent the vertical load of the front left wheel, the front right wheel, the rear left wheel, and the rear right wheel, respectively, and , and is a tire force weight matrix.

4. The method of claim 3, wherein, in a front wheel steering automobile physical constraint, when rear wheels of the vehicle cannot actively steer, left and right rear wheel steering angles are 0°, Reconstructing vehicle desired force matrix and the extended matrix of N matrix is realized by the following formula: wherein is the desired torque matrix for the vehicle is the reconstructed extended matrix, is the extended matrix for the N matrix; is the individual wheel angle, is the cornering stiffness, is the longitudinal velocity, lateral velocity, yaw rate, front wheel track, wheel base, is the longitudinal force, is the lateral force; a weighted pseudo-inverse matrix control quantity is realized through the following formula: ; wherein, is a longitudinal force, is a lateral force, is a control variable, said is equal to the vehicle distribution matrix , is a desired control variable, is a desired control command, said is equal to the vehicle desired force matrix .

5. The method of claim 3, wherein, when the tire force constraint conditions cannot be met, tire lateral forces are replaced by corrected lateral forces, and tire longitudinal forces are replaced by corrected longitudinal forces, and this is realized through the following formula: wherein, respectively represent the corrected longitudinal force and lateral force, and μ is a road friction coefficient, is a vertical force.

6. The method of claim 2, wherein, the control of the wheel steering angles and the driving torques of the vehicle according to the distributed tire force matrix is realized through the following formula: wherein, is the individual wheel angle, is the cornering stiffness, are the longitudinal velocity, lateral velocity, yaw rate, front wheel track, wheel base, is the drive torque, is the tire moment of inertia, is the wheel rotational speed, is the wheel rolling radius, is the wheel rolling resistance, is the wheel angular acceleration.

7. A tire force distribution device characterized by, comprise: an acquisition module that acquires vehicle driving state information and center line position information of a target road; a first processing module that determines a vehicle expected force matrix of vehicle driving according to the vehicle driving state information and the center line position information; a second processing module that performs tire force distribution according to the vehicle expected force matrix, tire force constraint conditions and a pseudo-inverse matrix, and ensures that a vehicle distribution force matrix corresponding to the distributed tire force matrix is minimum in error with the vehicle expected force matrix, wherein the pseudo-inverse matrix is a pseudo-inverse matrix realized based on a tire force weight matrix; an execution module that controls wheel steering angles and driving torques of the vehicle according to the distributed tire force matrix.

8. A tire force distribution apparatus characterized by, comprise: a processor and a memory; the memory stores computer execution instructions; the processor executes the computer execution instructions stored in the memory, so that the distribution device executes the method in any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that, The computer readable storage medium stores computer execution instructions, and the computer execution instructions are executed by the processor to realize the tire force distribution method in any one of claims 1 to 7.

10. A program product comprising a computer program, characterized in that The computer program is executed by the processor to realize the method in any one of claims 1 to 6.

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