Transverse control method, device and equipment for real vehicle driving assistance and storage medium

Abstract

The embodiment of the invention relates to the technical field of intelligent driving, and discloses an auxiliary transverse control method, device and equipment for real vehicle driving and a storage medium, and the method comprises the steps: obtaining a specified curve radius, and a test steering wheel rotation angle and an initial feed-forward rotation angle under a specified vehicle speed; calculating a feed-forward rotation angle according to the initial feed-forward rotation angle and the test steering wheel rotation angle; the maximum steering wheel angle constraint and the maximum steering wheel angle change rate of the MPC are obtained; establishing an MPC lateral solver according to the MPC maximum steering wheel angle constraint and the maximum steering wheel angle change rate to calculate a feedback angle; according to the feed-forward rotation angle and the feedback rotation angle, the current curve radius and the current steering wheel rotation angle under the current vehicle speed are calculated; and obtaining a steering wheel turning angle instruction of the next control period according to the current steering wheel turning angle. The method is simple in step and clear in process, the real vehicle driving auxiliary transverse control can be rapidly established and implemented, the riding comfort of passengers is considered when the transverse control is established, and the feasibility is high.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of intelligent driving technology, and specifically to a method, device, equipment and storage medium for real vehicle driving assistance lateral control. Background Art

[0002] The control of driving assistance relies on control methods such as MPC, LQR, and PID. The steering wheel angle calculated by these control methods usually includes a feedforward angle and a feedback angle. The feedforward angle is mainly used to adapt to driving on different curves, and the feedback angle is mainly used to reduce the lateral deviation and heading deviation between the driving process and the expected path.

[0003] For a curve of a certain radius, if the feedforward angle is too small, it will cause understeer. If the feedforward angle is too large, it will cause oversteer. In both cases, the driving assistance lateral control will have difficulty in controlling the vehicle to drive along the desired path.

[0004] The inaccuracy of the feedforward steering angle requires the feedback control to have a higher sensitivity to compensate. However, the higher feedback control sensitivity can easily lead to control oscillations and steering jitter, which in turn causes the vehicle to shake during driving, bringing an uncomfortable driving experience.

[0005] In the prior art, for a certain new model, the existing method for determining the parameters of the existing vehicle driving assistance lateral control is that the driving assistance developer sets preliminary parameters based on experience, debugs the parameters on the HIL platform, and then calibrates the actual vehicle for the test scenarios specified by the regulations. However, there are differences between the vehicle model of the HIL platform and the dynamic response of the actual vehicle, which is particularly obvious at high speeds. The calibration from the HIL platform to the actual vehicle is seriously affected by the experience of the developers, which will lead to a significant extension of the development cycle and a huge consumption of manpower and time resources. In addition, the test scenarios specified by the regulations cannot cover all the actual road scenarios of the actual vehicle on the road. Some uncovered scenarios may have obvious defects or even safety hazards. Therefore, the robustness of the data calibrated under the test scenarios specified by the regulations for new scenarios is difficult to guarantee. Summary of the invention

[0006] The embodiments of the present invention aim to solve the problems of the prior art method for determining parameters of vehicle driving assistance lateral control, which is seriously affected by the experience of developers, has a long development cycle, consumes a lot of manpower and time resources, and the robustness of the data calibrated under the scenes specified by the test regulations for new scenes is difficult to ensure. A method, device, equipment and storage medium for real vehicle driving assistance lateral control are provided.

[0007] According to an object of an embodiment of the present invention, a method for lateral control of real vehicle driving assistance is provided, comprising the following steps:

[0008] Get the test steering wheel angle at the specified curve radius and vehicle speed;

[0009] Obtain vehicle parameters, and calculate the current curve radius and the initial feedforward turning angle at the current vehicle speed based on the vehicle parameters;

[0010] Obtaining a feedforward gain coefficient according to an initial feedforward steering angle and a test steering wheel steering angle, and calculating a feedforward steering angle according to the feedforward gain coefficient;

[0011] Get the MPC maximum steering wheel angle constraint and maximum steering wheel angle change rate;

[0012] A vehicle dynamics MPC lateral solver is established according to the MPC maximum steering wheel angle constraint and the maximum steering wheel angle change rate to calculate the feedback angle;

[0013] Calculate the current steering wheel angle at the current curve radius and the current vehicle speed based on the feedforward angle and the feedback angle;

[0014] A steering wheel angle command for the next control cycle is obtained according to the current steering wheel angle.

[0015] In some optional implementations, the MPC maximum steering wheel angle constraint is obtained by:

[0016] According to the maximum centripetal acceleration of the vehicle, the maximum steering wheel angle limit at the current vehicle speed is calculated through the vehicle kinematic model;

[0017] Get the current curve radius and the feedforward turning angle at the current vehicle speed;

[0018] The MPC maximum steering wheel angle constraint is obtained according to the maximum steering wheel angle limit and the feedforward angle.

[0019] In some optional implementations, the MPC maximum steering wheel angle constraint is:

[0020] The difference between the feedforward angle and the maximum steering wheel angle limit is equal to the difference between the maximum steering wheel angle limit and the feedforward angle.

[0021] In some optional implementations, the maximum steering wheel angle change rate is obtained by:

[0022] According to the maximum centripetal acceleration of the vehicle, the maximum steering wheel angle change rate at the current vehicle speed is calculated through the vehicle kinematic model.

[0023] In some optional implementations, obtaining the steering wheel angle command specifically includes:

[0024] Obtaining a feasible range of the steering wheel angle for the next control cycle according to the current steering wheel angle and the maximum steering wheel angle change rate;

[0025] The steering wheel angle command for the next control cycle is limited by the steering wheel angle feasible range.

[0026] In some optional implementations, the feasible range of the steering wheel angle is:

[0027] The difference between the current steering wheel angle and the maximum steering wheel angle change rate to the sum of the current steering wheel angle and the maximum steering wheel angle change rate;

[0028] The steering wheel angle command is specifically:

[0029] When the steering wheel angle command is within the feasible steering wheel angle range, the steering wheel angle command remains unchanged;

[0030] When the steering wheel angle command is greater than the maximum value of the steering wheel angle feasible interval, the steering wheel angle command is the maximum value of the steering wheel angle feasible interval;

[0031] When the steering wheel angle command is less than the minimum value of the steering wheel angle feasible interval, the steering wheel angle command is the minimum value of the steering wheel angle feasible interval.

[0032] In some optional implementations, the vehicle parameters include: distance from the center of mass to the front axle, distance from the center of mass to the rear axle, mass, front wheel cornering stiffness, rear wheel cornering stiffness, heading feedback coefficient, and steering gear ratio.

[0033] According to another object of an embodiment of the present invention, a lateral control device for assisting driving of a real vehicle is provided, comprising:

[0034] A data acquisition module is used to obtain the test steering wheel angles under different specified curve radii and different specified vehicle speeds, and record the corresponding relationship between the different specified curve radii, different specified vehicle speeds and the corresponding test steering wheel angles;

[0035] The first calculation module is used to calculate and determine vehicle parameters, and calculate the initial feedforward angle at the current curve radius and the current vehicle speed according to the vehicle parameters, and calculate the feedforward angle in combination with the test steering wheel angle;

[0036] A second calculation module is used to obtain an MPC maximum steering wheel angle constraint and a maximum steering wheel angle change rate, and establish a vehicle dynamics MPC lateral solver according to the MPC maximum steering wheel angle constraint and the maximum steering wheel angle change rate to calculate a feedback angle;

[0037] and a third calculation module, for calculating a current steering wheel angle according to the feedforward angle and the feedback angle, and obtaining a steering wheel angle command for a next control cycle according to the current steering wheel angle.

[0038] According to another object of an embodiment of the present invention, there is provided a device for real vehicle driving assistance lateral control, comprising: a processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other through the communication bus;

[0039] The memory is used to store at least one executable instruction, and the executable instruction enables the processor to perform the operations of the real vehicle driving assistance lateral control method as described above.

[0040] According to another object of an embodiment of the present invention, a computer-readable storage medium is provided, wherein instructions are stored on the computer-readable storage medium, and when the instructions are executed by a processor, the steps of the method for lateral control of real vehicle driving assistance as described above are implemented.

[0041] Compared with the prior art, the present invention has the following advantages:

[0042] The method for lateral control for actual vehicle driving assistance provided by the present invention collects test steering wheel angles at different curve radii and different vehicle speeds through an actual vehicle, performs reverse fitting under fixed vehicle parameters, calculates a feedforward gain coefficient, and thus calculates a feedforward angle, reduces sensitivity for feedback, reduces control oscillation, and simultaneously considers driving experience, limits the maximum steering wheel angle constraint and the maximum steering wheel angle change rate of the vehicle under different conditions, and outputs a steering wheel angle command for the next control cycle; the method of the present invention has simple steps and clear processes, can realize rapid establishment and implementation of lateral control for actual vehicle driving assistance, and considers the riding comfort of passengers when constructing lateral control, has strong feasibility, can be quickly deployed in various types of passenger vehicles, and reduces time and human resource consumption.

[0043] The above description is only an overview of the technical solution of the embodiment of the present invention. In order to more clearly understand the technical means of the embodiment of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiment of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawings are only used to illustrate the embodiments and are not to be considered as limiting the present invention. In addition, the same reference symbols are used to represent the same components throughout the accompanying drawings. In the accompanying drawings:

[0045] Figure 1 A schematic diagram of a flow chart of a method for lateral control of real vehicle driving assistance provided by an embodiment of the present invention is shown;

[0046] Figure 2 A schematic structural diagram of a driving assistance lateral control device for a real vehicle provided by an embodiment of the present invention is shown;

[0047] Figure 3 A schematic structural diagram of a lateral control device for assisting driving of a real vehicle provided by an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0048] Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0049] This embodiment aims to solve the problems of the existing method for determining parameters of vehicle driving assistance lateral control, which is seriously affected by the experience of developers, has a long development cycle, consumes a lot of manpower and time resources, and the data calibrated under the scenes specified by the test regulations is difficult to ensure the robustness of the new scenes. A method for real vehicle driving assistance lateral control is provided.

[0050] Figure 1 A schematic diagram of a process flow for real vehicle driving assisted lateral control provided by an embodiment of the present invention is shown.

[0051] This embodiment provides a method for lateral control of real vehicle driving assistance, such as Figure 1 As shown, the following steps are included:

[0052] S10. Obtain a test steering wheel angle at a specified curve radius and a specified vehicle speed.

[0053] In this step, the actual steering wheel angles under different curve radii and specified vehicle speeds are collected from the real vehicle, which is the test steering wheel angle described in this step.

[0054] S20. Obtain vehicle parameters, and calculate the current curve radius and the initial feedforward turning angle at the current vehicle speed based on the vehicle parameters.

[0055] In this step, vehicle parameters are calculated based on vehicle calibration parameters, and the vehicle parameters include: distance from center of mass to front axle, distance from center of mass to rear axle, mass, front wheel cornering stiffness, rear wheel cornering stiffness, heading feedback coefficient, and steering transmission ratio.

[0056] Then the current curve radius and the initial feedforward turning angle at the current vehicle speed are calculated based on the vehicle parameters.

[0057] In this step, the current curve radius and the current vehicle speed are the same as or similar to the designated curve radius and the designated vehicle speed in step S10.

[0058] S30. Obtain a feedforward gain coefficient according to the initial feedforward angle and the test steering wheel angle, and calculate the feedforward angle according to the feedforward gain coefficient.

[0059] In this step, the proportionality coefficient between the test steering wheel angle and the initial feedforward angle is calculated to obtain the feedforward gain coefficient;

[0060] The feedforward angle is calculated by multiplying the feedforward gain coefficient by the feedforward angle formula.

[0061] In this step, the feedforward gain coefficients under different curve radii and different vehicle speeds can be obtained, and a feedforward gain coefficient table can be made. Then, the feedforward gain coefficient table corresponding to the current curve radius and the current vehicle speed can be extracted from the feedforward gain coefficient table to improve the accuracy of feedforward control.

[0062] S40. Obtain the MPC maximum steering wheel angle constraint and the maximum steering wheel angle change rate.

[0063] In this step, the maximum steering wheel angle limit at different vehicle speeds is calculated through the vehicle kinematic model according to the vehicle's maximum centripetal acceleration; the maximum steering wheel angle limit at the current vehicle speed is extracted, and the MPC maximum steering wheel angle constraint is obtained based on the maximum steering wheel angle limit and the feedforward angle calculated above.

[0064] At the same time, according to the maximum centripetal acceleration of the vehicle, the maximum steering wheel angle change rate at the current vehicle speed is calculated through the vehicle kinematic model.

[0065] In this step, the influence of wheel slip is ignored when calculating the MPC maximum steering wheel angle constraint and the maximum steering wheel angle change rate; and the vehicle speed is constant when calculating the maximum steering wheel angle change rate.

[0066] S50. Establish a vehicle dynamics MPC lateral solver according to the MPC maximum steering wheel angle constraint and the maximum steering wheel angle change rate to calculate the feedback angle.

[0067] In this step, the MPC maximum steering wheel angle constraint is obtained based on the feedforward angle calculated in the previous step and the maximum steering wheel angle limit.

[0068] The MPC maximum steering wheel angle constraint is the interval between the difference between the feedforward angle and the maximum steering wheel angle limit and the difference between the maximum steering wheel angle limit and the feedforward angle.

[0069] Then, a vehicle dynamics MPC lateral solver is established according to the maximum steering wheel angle change rate, and the feedback angle is solved by the vehicle dynamics MPC lateral solver.

[0070] S60. Calculate the current steering wheel angle at the current curve radius and the current vehicle speed according to the feedforward angle and the feedback angle.

[0071] In this step, based on the feedforward angle and feedback angle calculated in the above steps, the feedforward angle and feedback angle are summed to obtain the current steering wheel angle at the current curve radius and the current vehicle speed.

[0072] S70. Obtain a steering wheel angle command for the next control cycle according to the current steering wheel angle.

[0073] In this step, the steering wheel angle command for the next control cycle is obtained based on the current steering wheel angle, so that the steering wheel angle command is given to the EPS to achieve lateral control of real vehicle driving assistance.

[0074] In this step, specifically: obtaining a feasible range of the steering wheel angle for the next control cycle according to the current steering wheel angle and the maximum steering wheel angle change rate.

[0075] The steering wheel angle command for the next control cycle is limited by the steering wheel angle feasible range.

[0076] Among them, the feasible range of steering wheel angle is:

[0077] The difference between the current steering wheel angle and the maximum steering wheel angle change rate is equal to the sum of the current steering wheel angle and the maximum steering wheel angle change rate.

[0078] The steering wheel angle command is as follows:

[0079] When the steering wheel angle command is within the feasible steering wheel angle range, the steering wheel angle command remains unchanged, that is, the steering wheel angle command of the next control cycle is the same as the current steering wheel angle.

[0080] When the steering wheel angle command is greater than the maximum value of the steering wheel angle feasible interval, the steering wheel angle command of the next control cycle is the maximum value of the steering wheel angle feasible interval.

[0081] When the steering wheel angle command is smaller than the minimum value of the steering wheel angle feasible interval, the steering wheel angle command of the next control cycle is the minimum value of the steering wheel angle feasible interval.

[0082] According to the above steps, the steering wheel angle instructions under different curve radii and different vehicle speeds can be calculated, so that the lateral control of driving assistance can be quickly established and implemented in the actual vehicle.

[0083] Therefore, the lateral control method for actual vehicle driving assistance provided by the embodiment of the present invention collects test steering wheel angles at different curve radii and different vehicle speeds through the actual vehicle, performs reverse fitting under fixed vehicle parameters, calculates the feedforward gain coefficient, and thus calculates the feedforward angle, so as to reduce the sensitivity of feedback and reduce the control oscillation. At the same time, the driving experience is considered, the maximum steering wheel angle constraint and the maximum steering wheel angle change rate of the vehicle under different conditions are limited, and the steering wheel angle command for the next control cycle is output. The method of the present invention has simple steps and clear processes, and can be quickly established and implemented in actual vehicle driving assistance lateral control. The passenger comfort is considered when constructing lateral control, and it has strong feasibility and can be quickly deployed in various types of passenger vehicles to reduce time and human resource consumption.

[0084] In some optional embodiments, the process of acquiring the test steering wheel angle is optimized.

[0085] For example, in the process of real vehicle data collection, different curve radii and different vehicle speeds are specified, the corresponding test steering wheel angles are collected, and the correspondence between the curve radius, vehicle speed, and test steering wheel angle is recorded.

[0086] The corresponding relationship can be seen in the following table:

[0087]

[0088] In the above table, × indicates that the vehicle cannot accelerate to this speed under the turning radius. The above relationship table is only used as an example for data collection. The specific correspondence between the turning radius, vehicle speed and steering wheel angle shall be subject to actual measurement.

[0089] Through the above data collection, the test steering wheel angles under different curve radii and different vehicle speeds can be known. When the actual vehicle is controlled laterally, the corresponding test steering wheel angle can be directly extracted according to the current curve radius and current vehicle speed.

[0090] In some optional embodiments, the calculation scheme of the feedforward angle is optimized.

[0091] In this process, the vehicle parameters are first calculated based on the vehicle calibration parameters, and the vehicle parameters include: distance from the center of mass to the front axle, distance from the center of mass to the rear axle, mass, front wheel cornering stiffness, rear wheel cornering stiffness, heading feedback coefficient, and steering transmission ratio.

[0092] Then, based on the vehicle parameters, the initial feedforward turning angle at different curve radii and vehicle speeds is calculated.

[0093] The initial feedforward angle is calculated using a feedforward angle formula.

[0094] Specifically: initial feedforward angle = 1 / radius*(lf+lr-lr*k3+(mass*vx*vx / (lf+lr))*((lr / Cɑf)-(lf / Cɑr)+(lf / Cɑr)*k3))*180 / pi*steer_ratio.

[0095] Among them, radius represents the radius of the curve, lf represents the distance from the center of mass to the front axle, lr represents the distance from the center of mass to the rear axle, k3 represents the heading feedback coefficient, mass represents the mass, vx represents the vehicle speed, Cɑf represents the front wheel cornering stiffness, Cɑr represents the rear wheel cornering stiffness, and steer_ratio represents the steering gear ratio.

[0096] Then calculate the proportional coefficient between the test steering wheel angle and the initial feedforward angle to obtain the feedforward gain coefficient.

[0097] Therefore, different vehicle speeds, different curve radii and the corresponding feedforward gain coefficients are obtained through this embodiment, and then the feedforward gain coefficients and the corresponding vehicle speeds and curve radii are stored in the following table.

[0098]

[0099] Through the calculation of the above data, we can know the initial feedforward angle under different curve radii and different vehicle speeds. Combined with the curve radius and the corresponding vehicle speed, we can calculate the corresponding feedforward gain coefficient under different curve radii and different vehicle speeds. When performing lateral control of the actual vehicle, we can directly extract the corresponding feedforward gain coefficient according to the current curve radius and current vehicle speed.

[0100] Through the feedforward gain coefficient calculated above, during the lateral control of the actual vehicle, the current feedforward angle can be calculated according to the product of the feedforward gain coefficient and the feedforward angle formula. The feedforward angle formula refers to the calculation formula of the initial feedforward angle mentioned above. Therefore, the calculation formula of the current feedforward angle is as follows:

[0101] Feedforward angle = 1 / radius*(lf+lr-lr*k3+(mass*vx*vx / (lf+lr))*((lr / Cɑf)-(lf / Cɑr)+(lf / Cɑr)*k3))*180 / pi*steer_ratio*feedforward gain coefficient.

[0102] Among them, radius represents the radius of the curve, lf represents the distance from the center of mass to the front axle, lr represents the distance from the center of mass to the rear axle, k3 represents the heading feedback coefficient, mass represents the mass, vx represents the vehicle speed, Cɑf represents the front wheel cornering stiffness, Cɑr represents the rear wheel cornering stiffness, and steer_ratio represents the steering gear ratio.

[0103] In some optional embodiments, the specific calculation process of the MPC maximum steering wheel angle constraint is optimized.

[0104] In this embodiment, the acquisition of the MPC maximum steering wheel angle constraint includes:

[0105] According to the vehicle's maximum centripetal acceleration, the maximum steering wheel angle limit at the current vehicle speed is calculated through the vehicle kinematic model.

[0106] In this embodiment, when calculating the maximum steering wheel angle limit through the vehicle kinematic model, the influence of wheel side slip is ignored and calculated through the following formula:

[0107] yitamax=atan2(anmax*(lf+lr) / vx / vx)*180 / pi*steer_ratio

[0108] Among them, yitamax represents the maximum steering wheel angle limit, anmax represents the maximum centripetal acceleration of the vehicle, lf represents the distance from the center of mass to the front axle, lr represents the distance from the center of mass to the rear axle, vx represents the vehicle speed, and steer_ratio represents the steering gear ratio.

[0109] After the maximum steering wheel angle limit is calculated by the above formula, the feedforward angle at the current curve radius and current vehicle speed is extracted.

[0110] Then, the MPC maximum steering wheel angle constraint is obtained according to the maximum steering wheel angle limit and the feedforward angle.

[0111] Specifically, the MPC maximum steering wheel angle constraint is an interval from the difference between the feedforward angle and the maximum steering wheel angle limit to the difference between the maximum steering wheel angle limit and the feedforward angle, so as to obtain the MPC maximum steering wheel angle constraint.

[0112] In addition, in this embodiment, after obtaining the MPC maximum steering wheel angle constraint, the maximum steering wheel angle change rate is also required to establish a vehicle dynamics MPC lateral solver.

[0113] Among them, when calculating the maximum steering wheel angle change rate, the influence of wheel side slip is ignored, and the vehicle kinematics is used, assuming that the vehicle speed is constant in a short period of time, and the maximum steering wheel angle change rate at different speeds is obtained by limiting the vehicle's maximum centripetal acceleration.

[0114] In this embodiment, when calculating the maximum steering wheel angle change rate limit through the vehicle kinematic model, the wheel side slip effect is ignored and calculated through the following formula:

[0115] yitadotmax≈Jnmax*L / vx / vx*180 / pi*steer_ratio

[0116] Among them, yitadotmax represents the maximum steering wheel angle change rate, Jnmax represents the maximum centripetal acceleration of the vehicle, vx represents the vehicle speed, and steer_ratio represents the steering gear ratio.

[0117] In this embodiment, a vehicle dynamics MPC lateral solver is established by using the MPC maximum steering wheel angle constraint and the maximum steering wheel angle change rate calculated above, and the feedback angle is solved by using the vehicle dynamics MPC lateral solver.

[0118] Among them, it should be clarified that the vehicle kinematic model is an existing technology, which uses the vehicle's lateral position, lateral position change rate, yaw angle, and yaw angle change rate as state quantities to construct the vehicle's lateral dynamics model state space equation.

[0119] According to the state equation, the response of the vehicle's lateral displacement, lateral velocity, yaw angle, and yaw angular velocity under a given front wheel steering angle input can be analyzed to achieve lateral tracking to reduce lateral tracking deviation.

[0120] In the present embodiment, on the basis of the constructed state-space equation of the vehicle lateral dynamics model, the influence of wheel side slip and road curvature is ignored, and the vehicle's lateral position error, lateral position error change rate, yaw angle error, and yaw angle error change rate are used as state quantities to construct the vehicle lateral dynamics model tracking error state-space equation, that is, the vehicle dynamics MPC lateral solver described in the present embodiment, thereby solving and obtaining the feedback angle.

[0121] For example:

[0122] The vehicle dynamics MPC lateral solver constructed is as follows:

[0123]

[0124] in, is the error state variable; Iz is the vehicle moment of inertia, e1 is the lateral deviation, and e2 is the heading deviation;

[0125]

[0126]

[0127] Bd=b*T

[0128] X(k+1)=AdX(k)+Bdδ(k)

[0129] After the feedback angle is calculated by the vehicle dynamics MPC lateral solver, the feedforward angle corresponding to the curve radius and the corresponding vehicle speed is extracted, and the feedforward angle and the feedback angle are summed to obtain the current steering wheel angle at the current curve radius and the current vehicle speed.

[0130] Then, based on the current steering wheel angle, the steering wheel angle command for the next control cycle is obtained, and the steering wheel angle command is given to the EPS to realize lateral control of real vehicle driving assistance.

[0131] In some optional embodiments, an LQR controller or a PID controller may be used to calculate the feedback angle.

[0132] In the present embodiment, the method for lateral control for driving assistance of a real vehicle collects test steering wheel angles at different curve radii and different vehicle speeds through a real vehicle, performs reverse fitting under fixed vehicle parameters, calculates a feedforward gain coefficient, and thus calculates a feedforward angle, so as to reduce sensitivity for feedback and reduce control oscillation. Meanwhile, the driving experience is considered, the maximum steering wheel angle constraint and the maximum steering wheel angle change rate of the vehicle are limited under different conditions, and a steering wheel angle command for the next control cycle is output. The method of the present invention has simple steps and clear processes, and can realize rapid establishment and implementation of lateral control for driving assistance of a real vehicle, and takes into account the riding comfort of the passengers when constructing the lateral control. It has strong feasibility and can be quickly deployed in various types of passenger vehicles, thereby reducing time and human resource consumption.

[0133] In some optional embodiments, the embodiments of the present invention further disclose a lateral control device for assisting driving of a real vehicle.

[0134] like Figure 2 As shown, the lateral control device for assisting driving of a real vehicle includes: a data acquisition module 100 , a first calculation module 200 , a second calculation module 300 , and a third calculation module 400 .

[0135] The data acquisition module 100 is used to obtain the test steering wheel angles under different specified curve radii and different specified vehicle speeds, and to record the corresponding relationship between the different specified curve radii, different specified vehicle speeds and the corresponding test steering wheel angles.

[0136] The data acquisition module 100 realizes the actual vehicle collection of the actual steering wheel angles at different curve radii and specified vehicle speeds, which is the test steering wheel angle described in this step, and stores it so that the test steering wheel angle at the specified curve radius and specified vehicle speed can be directly extracted later.

[0137] The first calculation module 200 is used to calculate and determine vehicle parameters, and calculate the current curve radius and the initial feedforward angle at the current vehicle speed based on the vehicle parameters, and calculate the feedforward angle in combination with the test steering wheel angle.

[0138] When calculating the feedforward angle, the first calculation module 200 first extracts and calculates the vehicle parameters, then calculates the initial feedforward angle at the current curve radius and the current vehicle speed based on the vehicle parameters, and calculates the proportional coefficient between the test steering wheel angle and the initial feedforward angle based on the initial feedforward angle to obtain the feedforward gain coefficient, and finally calculates the feedforward angle by multiplying the feedforward gain coefficient by the feedforward angle formula.

[0139] The first calculation module 200 can be used to obtain feedforward gain coefficients under different curve radii and different vehicle speeds, and to create a feedforward gain coefficient table. Then, the feedforward gain coefficient table corresponding to the current curve radius and the current vehicle speed is extracted from the feedforward gain coefficient table to improve the accuracy of feedforward control.

[0140] The second calculation module 300 is used to obtain the MPC maximum steering wheel angle constraint and the maximum steering wheel angle change rate, and establish a vehicle dynamics MPC lateral solver according to the MPC maximum steering wheel angle constraint and the maximum steering wheel angle change rate to calculate the feedback angle.

[0141] When calculating the feedback angle, the second calculation module 300 first calculates the maximum steering wheel angle limit through the maximum centripetal acceleration of the vehicle to obtain the MPC maximum steering wheel angle constraint, and then establishes a vehicle dynamics MPC lateral solver in combination with the maximum steering wheel angle change rate calculated through the maximum centripetal acceleration of the vehicle, thereby calculating the feedback angle.

[0142] The third calculation module 400 is used to calculate the current steering wheel angle according to the feedforward angle and the feedback angle, and obtain the steering wheel angle command of the next control cycle according to the current steering wheel angle.

[0143] When calculating the steering wheel angle command for the next control cycle, the third calculation module 400 first extracts the feedforward angle calculated by the first calculation module 200 and the feedback angle calculated by the second calculation module 300, calculates the current steering wheel angle, and then obtains the feasible range of the steering wheel angle for the next control cycle according to the current steering wheel angle and the maximum steering wheel angle change rate. Finally, the steering wheel angle command for the next control cycle is limited by the feasible range of the steering wheel angle, and the steering wheel angle command is given to the EPS to realize lateral control of real vehicle driving assistance.

[0144] In this embodiment, the specific implementation process of calculating the feedforward angle through the first calculation module 200, calculating the feedback angle through the second calculation module 300, and calculating the current steering wheel angle and the steering wheel angle command of the next control cycle through the third calculation module 400 refers to the calculation process in the above-mentioned actual vehicle driving assistance lateral control method, which will not be repeated in this embodiment.

[0145] In some optional embodiments, the embodiments of the present invention further disclose a lateral control device for assisting driving of a real vehicle.

[0146] Figure 3 A schematic structural diagram of a lateral control device for assisting driving of a real vehicle provided by an embodiment of the present invention is shown.

[0147] like Figure 3 As shown, the abnormal vehicle detection and safety reminder device includes: a processor 510, a memory 520, a communication interface 530 and a communication bus 540. The processor 510, the memory 520 and the communication interface 530 communicate with each other through the communication bus 540.

[0148] In this embodiment, the memory 520 is used to store at least one executable instruction, and the executable instruction enables the processor 520 to perform the operation of the real vehicle driving assistance lateral control method as described in any of the above embodiments; the communication interface 530 is used to communicate with network elements of other devices such as clients or other servers. The processor 510 is used to execute the program 550, and specifically can execute the relevant steps in the above embodiment of the real vehicle driving assistance lateral control method.

[0149] Specifically, the program 550 may include program code including computer-executable instructions.

[0150] The processor 510 may be a central processing unit (CPU), or an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiment of the present invention. The one or more processors included in the real vehicle driving assistance lateral control device may be processors of the same type, such as one or more CPUs; or processors of different types, such as one or more CPUs and one or more ASICs.

[0151] The memory 520 is used to store the program 550. The memory 520 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0152] The program 550 may be specifically called by the processor 510 to enable the real vehicle driving assistance lateral control device to execute the operations of the real vehicle driving assistance lateral control method described in any of the above embodiments.

[0153] In some optional embodiments, the embodiments of the present invention further disclose a computer-readable storage medium, wherein at least one executable instruction is stored in the storage medium. When the executable instruction is run on the device / apparatus for assisting lateral control of real vehicle driving, the device / apparatus for assisting lateral control of real vehicle driving enables the device / apparatus for assisting lateral control of real vehicle driving to execute the steps of the method for assisting lateral control of real vehicle driving in any of the above-mentioned method embodiments.

[0154] The specific implementation process of the real vehicle driving assistance lateral control method described in this embodiment can be found in any of the above method embodiments, and will not be repeated in this embodiment.

[0155] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. Similarly, in order to simplify the present invention and help understand one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, the various features of the embodiments of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. Wherein, the claims that follow the specific embodiment are hereby expressly incorporated into the specific embodiment, wherein each claim itself is a separate embodiment of the present invention.

[0156] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments may be combined into one module or unit or component, and further may be divided into a plurality of submodules or subunits or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive.

[0157] It should be noted that the above embodiments illustrate the present invention rather than limit it, and that those skilled in the art may devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets shall not be construed as a limitation on the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present invention may be implemented by means of hardware comprising a number of different elements and by means of a suitably programmed computer. In a unit claim enumerating a number of devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third, etc. does not indicate any order. These words may be interpreted as names. The steps in the above embodiments, unless otherwise specified, should not be understood as limitations on the order of execution.

Claims

1. A lateral control method for real vehicle driving assistance, characterized in that: The following steps are involved: Get the test steering wheel angle at the specified curve radius and vehicle speed; Obtain vehicle parameters, and calculate the current curve radius and the initial feedforward turning angle at the current vehicle speed based on the vehicle parameters; Obtaining a feedforward gain coefficient according to an initial feedforward steering angle and a test steering wheel steering angle, and calculating a feedforward steering angle according to the feedforward gain coefficient; Get the MPC maximum steering wheel angle constraint and maximum steering wheel angle change rate; A vehicle dynamics MPC lateral solver is established according to the MPC maximum steering wheel angle constraint and the maximum steering wheel angle change rate to calculate the feedback angle; Calculate the current steering wheel angle at the current curve radius and the current vehicle speed based on the feedforward angle and the feedback angle; A steering wheel angle command for the next control cycle is obtained according to the current steering wheel angle.

2. The method for lateral control of real vehicle driving assistance according to claim 1, characterized in that: The acquisition of the MPC maximum steering wheel angle constraint is specifically as follows: According to the maximum centripetal acceleration of the vehicle, the maximum steering wheel angle limit at the current vehicle speed is calculated through the vehicle kinematic model; Get the current curve radius and the feedforward turning angle at the current vehicle speed; The MPC maximum steering wheel angle constraint is obtained according to the maximum steering wheel angle limit and the feedforward angle.

3. The method for lateral control of real vehicle driving assistance according to claim 2, characterized in that: The MPC maximum steering wheel angle constraint is: The difference between the feedforward angle and the maximum steering wheel angle limit is equal to the difference between the maximum steering wheel angle limit and the feedforward angle.

4. The method for lateral control of real vehicle driving assistance according to claim 1, characterized in that: The maximum steering wheel angle change rate is obtained as follows: According to the maximum centripetal acceleration of the vehicle, the maximum steering wheel angle change rate at the current vehicle speed is calculated through the vehicle kinematic model.

5. The method for lateral control of real vehicle driving assistance according to claim 1, characterized in that: The acquisition of steering wheel angle command includes: Obtaining a feasible range of the steering wheel angle for the next control cycle according to the current steering wheel angle and the maximum steering wheel angle change rate; The steering wheel angle command for the next control cycle is limited by the steering wheel angle feasible range.

6. The method for lateral control of real vehicle driving assistance according to claim 5, characterized in that: The feasible range of the steering wheel angle is: The difference between the current steering wheel angle and the maximum steering wheel angle change rate to the sum of the current steering wheel angle and the maximum steering wheel angle change rate; The steering wheel angle command is specifically: When the steering wheel angle command is within the feasible steering wheel angle range, the steering wheel angle command remains unchanged; When the steering wheel angle command is greater than the maximum value of the steering wheel angle feasible interval, the steering wheel angle command is the maximum value of the steering wheel angle feasible interval; When the steering wheel angle command is less than the minimum value of the steering wheel angle feasible interval, the steering wheel angle command is the minimum value of the steering wheel angle feasible interval.

7. The method for lateral control of real vehicle driving assistance according to claim 1, characterized in that: The vehicle parameters include: distance from the center of mass to the front axle, distance from the center of mass to the rear axle, mass, front wheel cornering stiffness, rear wheel cornering stiffness, heading feedback coefficient, and steering transmission ratio.

8. A lateral control device for driving assistance of a real vehicle, characterized in that: include: A data acquisition module is used to obtain the test steering wheel angles under different specified curve radii and different specified vehicle speeds, and record the corresponding relationship between the different specified curve radii, different specified vehicle speeds and the corresponding test steering wheel angles; The first calculation module is used to calculate and determine vehicle parameters, and calculate the initial feedforward angle at the current curve radius and the current vehicle speed according to the vehicle parameters, and calculate the feedforward angle in combination with the test steering wheel angle; A second calculation module is used to obtain an MPC maximum steering wheel angle constraint and a maximum steering wheel angle change rate, and establish a vehicle dynamics MPC lateral solver according to the MPC maximum steering wheel angle constraint and the maximum steering wheel angle change rate to calculate a feedback angle; and a third calculation module, for calculating a current steering wheel angle according to the feedforward angle and the feedback angle, and obtaining a steering wheel angle command for a next control cycle according to the current steering wheel angle.

9. A lateral control device for real vehicle driving assistance, characterized in that: include: A processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other via the communication bus; The memory is used to store at least one executable instruction, and the executable instruction enables the processor to perform the operation of the real vehicle driving assistance lateral control method as described in any one of claims 1-7.

10. A computer-readable storage medium having instructions stored thereon, characterized in that: When the instructions are executed by the processor, the steps of the method for lateral control of real vehicle driving assistance as described in any one of claim 17 are implemented.

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