An automatic steering control method and device

Abstract

The application provides an automatic steering control method and device, comprising the following steps: constructing a target function considering a lane changing path tracking error, an actuator energy consumption and an additional fuel consumption increase amount of steering; bringing a constraint condition into the target function to obtain an optimal steering control sequence for steering control of a vehicle; and obtaining the additional fuel consumption increase amount of steering based on a steering wheel angle and a vehicle speed. The fuel consumption factor is introduced into the target function, so that the steering control sequence with reduced driving resistance, fuel consumption, energy consumption and high path tracking precision is obtained.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automatic driving, in particular to an automatic steering control method and device. BACKGROUND

[0002] With the maturity of automatic driving technology, automatic driving vehicles are gradually applied in civilian fields. Commercial vehicles urgently need the promotion and application of automatic driving technology to reduce the burden on drivers and improve the driving quality of commercial vehicles.

[0003] Currently, the automatic steering control method for commercial vehicles generally only considers the tracking effect of the reference path and the energy consumption of the steering actuator during the design process. Specifically, during the design process of the lane-changing steering controller of the commercial vehicle, the expected vehicle lane-changing path is mainly considered, and a predictive optimal feedback control problem is constructed, the goal of which is to reduce the deviation between the actual driving path of the commercial vehicle and the expected driving path of the vehicle, and to achieve smooth lane-changing driving.

[0004] Currently, the lane-changing steering controller for commercial vehicles mainly uses methods such as PID control, linear quadratic programming, and model predictive control during the design process. With the increasing automation and intelligence of commercial vehicles, their oil-saving potential is further developed. During long-distance transportation, the number of lane changes is related to the surrounding traffic flow density, and the number of lane changes for a single trip is usually as many as several thousand times. Optimizing the driving resistance change during the lane-changing steering process is of great significance to further improve the oil-saving potential of commercial vehicles. SUMMARY

[0005] The present application provides an automatic steering control method and device to solve the above problems.

[0006] The present application provides an automatic steering control method, comprising: constructing a target function that takes into account the lane-changing path tracking error, actuator energy consumption, and additional steering oil consumption increase;

[0007] The constraint condition is brought into the target function, and the optimal steering control sequence is obtained by solving, which is used for steering control of the vehicle.

[0008] The additional steering oil consumption increase is obtained based on the steering wheel angle and the vehicle speed.

[0009] According to the automatic steering control method provided by the present application, the additional steering oil consumption increase is obtained based on the steering wheel angle and the vehicle speed, comprising: obtaining the weight corresponding to the steering wheel angle and the vehicle speed based on the vehicle dynamics model and the vehicle acceleration, respectively.

[0010] The vehicle steering wheel angle, the weight corresponding to the vehicle steering wheel angle, the vehicle speed, and the weight corresponding to the vehicle speed are weighted to obtain a steering additional fuel consumption increase.

[0011] According to the automatic steering control method, the target function is constructed by considering the lane-changing path tracking error, the actuator energy consumption, and the steering additional fuel consumption increase.

[0012] The lane-changing path tracking error is determined based on a difference between the actual position of the vehicle and the reference path position.

[0013] The sum of squares of the lane-changing path tracking error, the actuator energy consumption, and the steering additional fuel consumption increase is taken as the first target function.

[0014] According to the automatic steering control method, the target function is constructed by considering the lane-changing path tracking error, the actuator energy consumption, and the steering additional fuel consumption increase.

[0015] The lane-changing path tracking error is determined based on a difference between the actual position of the vehicle and the reference path position.

[0016] The sum of absolute values of the lane-changing path tracking error, the actuator energy consumption, and the steering additional fuel consumption increase is taken as the second target function.

[0017] According to the automatic steering control method, the target function is a target function corresponding to a lane-changing steering control problem.

[0018] Correspondingly, the constraint condition is brought into the target function, and an optimal steering control sequence is obtained by solving, which is used for steering control of the vehicle.

[0019] Based on the linearized steering dynamics constraint of the vehicle and the safety distance constraint of the vehicle, the target function corresponding to the lane-changing steering control problem is constructed as a target function corresponding to a constrained optimal control problem in a finite prediction time domain.

[0020] The first constraint condition and the second constraint condition are introduced; the first constraint condition is a vehicle dynamics state relationship; and the second constraint condition is that the steering wheel angle cannot exceed a preset maximum steering angle δb.

[0021] Based on the target function corresponding to the constrained optimal control problem, the first constraint condition, and the second constraint condition, a Lagrange target function considering the constraint condition is constructed.

[0022] The gradient descent method is used to iteratively update the Lagrange target function, and the optimal dynamics vehicle state and the optimal steering wheel control amount are calculated as the optimal steering control sequence.

[0023] According to the automatic steering control method provided by the application, after the gradient descent method is used to iteratively update the Lagrange objective function, the method further comprises:

[0024] The iteratively updated dynamic vehicle state and steering wheel control amount are constrained and protected by using a predetermined emergency collision avoidance control algorithm, so as to obtain the optimal dynamic vehicle state and the optimal steering wheel control amount as the optimal steering control sequence.

[0025] The application also provides an automatic steering control device, comprising: an objective function construction module, configured to construct an objective function considering the lane-changing path tracking error, actuator energy consumption and steering additional fuel consumption increase;

[0026] An optimal steering control sequence solving module is configured to bring the constraint condition into the objective function, and solve the optimal steering control sequence for steering control of the vehicle.

[0027] The steering additional fuel consumption increase is obtained based on the vehicle steering wheel angle and vehicle speed.

[0028] The application also provides an electronic device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements any of the above automatic steering control methods when executing the program.

[0029] The application also provides a non-transitory computer readable storage medium having a computer program stored thereon, wherein the computer program is executable by a processor to implement any of the above automatic steering control methods.

[0030] The automatic steering control method and device provided by the application can optimize the steering wheel angle control during the lane-changing steering control of the commercial vehicle, and can obtain the effects of reduced driving resistance, reduced fuel consumption, reduced energy consumption and high path tracking accuracy. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0032] Figure 1 is a flowchart of the automatic steering control method provided by the embodiments of the application.

[0033] Figure 2 is a structural block diagram of an automatic steering control device provided by an embodiment of the present application;

[0034] Figure 3 is a physical structure schematic diagram of an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0035] To make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described below in connection with the drawings in the present application. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0036] The existing automatic steering control method for commercial vehicles generally only considers the tracking effect on the reference path and the energy consumption of the steering actuator, and rarely considers the problem of increased fuel consumption caused by increased driving resistance in the steering process. The present application determines the automatic steering control scheme by taking into account the fuel consumption and energy consumption in the steering process, which is specifically described as follows.

[0037] Figure 1 is a flowchart of an automatic steering control method provided by an embodiment of the present application; as shown in Figure 1 , an automatic steering control method comprises the following steps:

[0038] S101, a target function is constructed by taking into account the lane changing path tracking error, actuator energy consumption and steering additional fuel consumption increase.

[0039] Among them, the steering additional fuel consumption increase is obtained based on the vehicle steering wheel angle and the vehicle speed.

[0040] In this step, first, the current steering wheel angle and vehicle speed information of the vehicle are obtained, and then according to the vehicle dynamics principle, the weighted combination of the steering wheel angle and the vehicle speed is combined into a polynomial of different orders or a linear superposition series of different terms to characterize the steering additional fuel consumption increase. For example, the weighted combination of the steering wheel angle and the vehicle speed is combined into a quadratic function In the formula, δ is the steering wheel angle, v x is the vehicle speed, and w1 and w2 are weighting coefficients.

[0041] The weighting coefficients in the above weighted combination process can be obtained according to the piecewise linear function of the vehicle speed and the steering wheel angle, or can be obtained by polynomial fitting of the actual measurement data.

[0042] After obtaining the steering additional fuel consumption increase amount characterized by the vehicle steering wheel angle and the vehicle speed, a target function is constructed by taking into account the lane-changing path tracking error, the actuator energy consumption and the steering additional fuel consumption increase amount, and the steering additional fuel consumption increase amount in the target function can be quadratic (i.e. In the formula, J is the target function, Pref is the reference path position, Q s is the steering additional fuel consumption increase amount, P s is the actuator energy consumption); or can be in the form of absolute value (i.e. J = |P-Pref| + |P s |+|Q s |, in which J is the target function, Pref is the reference path position, Q s is the steering additional fuel consumption increase amount, P s is the actuator energy consumption). Through different forms of target functions, the purpose of constructing a target function taking into account the lane-changing path tracking error, the actuator energy consumption and the steering additional fuel consumption increase amount can be achieved.

[0043] It should be noted that in the above steering additional fuel consumption increase amount characterization process, since the longitudinal component of the tire lateral force is opposite to the vehicle forward direction during steering, and the longitudinal component of the front axle lateral force is large during steering, the longitudinal component of the front axle tire lateral force is used to approximate the increase in fuel consumption. In addition, according to the principle of vehicle dynamics, the fuel consumption increase is closely related to the current steering wheel angle and vehicle speed, so the combination of the steering wheel angle and the vehicle speed into different order polynomials or different term linear superposition series is used as the characterization of the steering additional fuel consumption increase amount.

[0044] In addition, the commonly used target function only considers the tracking effect of the reference path and the energy consumption factor of the steering actuator, and the target function in the present application adds the above-mentioned steering additional fuel consumption increase amount factor, thereby constructing a target function mainly based on the lane-changing path tracking error, the actuator energy consumption and the fuel consumption increase, and further taking into account the energy consumption, stability and fuel consumption factors to achieve optimal automatic steering control.

[0045] S102, the constraint condition is brought into the target function, and an optimal steering control sequence is obtained by solving, which is used for steering control of the vehicle.

[0046] In this step, since the linearization steering dynamics constraint of the commercial vehicle and the safety distance constraint of the front and rear vehicles on the adjacent lane need to be considered, the fuel-saving lane-changing steering control problem is constructed as a constrained optimal control problem in a limited prediction time domain, i.e. the above-mentioned target function J is constructed as the sum of the target functions at each time in the limited prediction time domain J 总, specifically, set the prediction time domain T [1, 2, 3, …, k], then the target function at T1 is J1, the target function at T2 is J2, and so on, the target function at Tk is J k At this time, J 总 = J1+J2+J3+…+J k Correspondingly, the constraint condition becomes the vehicle dynamics state relationship and the steering wheel angle cannot exceed the preset maximum steering angle δb.

[0047] According to the above vehicle dynamics state relationship and the constraint condition related to the steering wheel angle, the sum of the target functions J 总 can be directly optimized and solved, or can be solved by simplifying the control problem, see the description below. By the above method, a series of optimal dynamic vehicle states and corresponding optimal steering wheel control amounts are obtained, thereby forming an optimal steering control sequence, and realizing automatic steering control of the vehicle.

[0048] The automatic steering control method provided by the embodiment of the present application characterizes the steering additional fuel consumption increase by the vehicle steering wheel angle and the vehicle speed, and constructs a target function considering the lane changing path tracking error, the actuator energy consumption and the steering additional fuel consumption increase, and then solves the optimal steering control sequence, so that the steering wheel angle control can be optimized in the commercial vehicle lane changing steering control process, and the effects of reduced driving resistance, reduced fuel consumption, reduced energy consumption and high path tracking accuracy are obtained.

[0049] In another embodiment provided by the present application, the steering additional fuel consumption increase is obtained based on the vehicle steering wheel angle and the vehicle speed, and includes: obtaining the weight corresponding to the vehicle steering wheel angle and the vehicle speed based on the vehicle dynamics model and the vehicle acceleration.

[0050] The steering additional fuel consumption increase is obtained by weighted calculation based on the vehicle steering wheel angle, the weight corresponding to the vehicle steering wheel angle, the vehicle speed and the weight corresponding to the vehicle speed.

[0051] In this embodiment, based on the above analysis of the relationship between the tire lateral force and the fuel consumption increase during the steering process of the commercial vehicle, the steering additional fuel consumption increase Q s is represented by combining the steering wheel angle and the vehicle speed into a quadratic function (i.e. the steering additional fuel consumption increase representation formula), which is:

[0052]

[0053] In the formula, δ is the vehicle steering wheel angle, v xV is the vehicle speed, w1 and w2 are weighting coefficients, and w1 and w2 are based on a vehicle dynamics model and a current vehicle acceleration value.

[0054] The automatic steering control method provided by the embodiment of the application combines the steering wheel angle and the vehicle speed into a quadratic function, thereby realizing representation of the steering additional fuel consumption increase, and introducing the steering additional fuel consumption increase into a target function, so that the optimal steering control sequence obtained can have the effects of saving fuel consumption, reducing energy consumption, and high path tracking accuracy.

[0055] In addition, the steering additional fuel consumption increase representation formula can also be a polynomial of different orders or a linear superposition series of different terms corresponding to the vehicle steering wheel angle and the vehicle speed, and the steering additional fuel consumption can be obtained through different representation forms, which is convenient for subsequent optimization and solution.

[0056] In another embodiment provided by the application, the target function considering the lane-changing path tracking error, the actuator energy consumption, and the steering additional fuel consumption increase includes:

[0057] The lane-changing path tracking error is determined based on a difference between the actual vehicle position and the reference path position.

[0058] The sum of squares of the lane-changing path tracking error, the actuator energy consumption, and the steering additional fuel consumption increase is taken as the first target function.

[0059] In the embodiment, the target function of the steering additional fuel consumption increase is:

[0060]

[0061] In the formula, P is the actual vehicle position, Pref is the reference path position, Q s is the steering additional fuel consumption increase, P s is the actuator energy consumption.

[0062] P-Pref is the deviation between the actual vehicle position and the reference path position, that is, represents the path tracking; the steering additional fuel consumption increase Q s is related to the fuel consumption and the actuator energy consumption P s After comprehensively considering the above three factors, the optimal solution is obtained, and the optimal steering control sequence obtained has the effects of saving fuel consumption, reducing energy consumption, and high path tracking accuracy.

[0063] In another embodiment provided by the application, the target function considering the lane-changing path tracking error, the actuator energy consumption, and the steering additional fuel consumption increase includes:

[0064] The lane-changing path tracking error is determined based on a difference between the actual vehicle position and the reference path position.

[0065] The sum of the lane-changing path tracking error, the actuator energy consumption, and the absolute value of the steering additional fuel consumption increase is taken as the second objective function.

[0066] In addition to constructing the objective function by a quadratic function, it can also be characterized in the form of absolute value, that is, J' = |P-Pref| + |P s |+|Q s | is smaller. Compared with the quadratic objective function, the second objective function J' in the embodiment is better for describing the actuator energy consumption and has a wider range of application. s or P s is smaller. Compared with the quadratic objective function, the second objective function J' in the embodiment is better for describing the actuator energy consumption and has a wider range of application.

[0067] In another embodiment provided by the application, the objective function is the objective function corresponding to the lane-changing steering control problem.

[0068] Correspondingly, the constraint condition is brought into the objective function, and an optimal steering control sequence is obtained by solving, which is used for steering control of the vehicle, including:

[0069] Based on the linearized steering dynamics constraint of the vehicle and the safety distance constraint of the vehicle, the objective function corresponding to the lane-changing steering control problem is constructed as an objective function corresponding to a constrained optimal control problem in a finite prediction time domain.

[0070] The first constraint condition and the second constraint condition are introduced; the first constraint condition is a vehicle dynamics state relationship; and the second constraint condition is that the steering wheel angle cannot exceed a preset maximum angle δb.

[0071] Based on the objective function corresponding to the constrained optimal control problem, the first constraint condition, and the second constraint condition, a Lagrange objective function considering the constraint condition is constructed.

[0072] The gradient descent method is used to iteratively update the Lagrange objective function, and the optimal dynamics vehicle state and the optimal steering wheel control amount are calculated as the optimal steering control sequence.

[0073] In the embodiment, the first objective function J is calculated, and specifically, after the objective function mainly based on the lane-changing path tracking error, the actuator energy consumption, and the steering additional fuel consumption increase is constructed, the fuel-saving lane-changing steering control problem is constructed as a constrained optimal control problem in a finite prediction time domain (i.e., T[1, 2, 3,..., k]) considering the linearized steering dynamics constraint of the commercial vehicle and the safety distance constraint of the front and rear vehicles on the adjacent lane, that is, the objective function is constructed as J 总 = J1+ J2+ J3+…+J k .

[0074] Further, a corresponding constraint condition 1 (i.e. a first constraint condition) and a constraint condition 2 (a second constraint condition) are introduced, wherein the constraint condition 1 is a vehicle dynamics state relationship In the formula, x is a vehicle state, and u is a steering wheel control amount; the constraint condition 2 is that a steering wheel rotation angle cannot exceed a preset maximum rotation angle δb.

[0075] Then, the target function J is simplified by using a target function piecewise linearization and a probability safety constraint method. 总 = J1+J2+J3+…+J k Specifically, the dynamic vehicle state x [1, 2, 3, …, k] and the steering wheel control amount u [1, 2, 3, …, k] are selected as variables, and a Lagrange target function considering the constraint condition is constructed as Wherein, λ1 and λ2 are Lagrange multipliers. And by using a gradient descent method, the Lagrange target function J_L is iteratively calculated, so that the optimal dynamic vehicle state sequence and the corresponding steering wheel control amount sequence are obtained, that is, the solution of the fuel-saving lane-changing optimal steering control problem.

[0076] In another embodiment provided by the application, the calculation is performed based on a second target function J', and the specific process is similar to the above-mentioned calculation process based on the first target function J, and the difference lies in that the fuel-saving lane-changing steering control problem is constructed as a constrained optimal control problem in a limited prediction time domain (i.e. T [1, 2, 3, …, k]), that is, the target function is constructed as 总 = J'1+J'2+J'3+…+J' k .

[0077] The Lagrange target function considering the constraint condition is Wherein, λ1 and λ2 are Lagrange multipliers. And by using a gradient descent method, the Lagrange target function J_L is iteratively calculated, so that the optimal dynamic vehicle state sequence and the corresponding steering wheel control amount sequence are obtained, that is, the solution of the fuel-saving lane-changing optimal steering control problem.

[0078] The automatic steering control method provided by the embodiment of the application simplifies the target function by using a target function piecewise linearization and a probability safety constraint method, thereby reducing the complexity of the fuel-saving lane-changing optimal steering control problem, facilitating the rolling horizon optimization solution, saving time, and thereby meeting the real-time requirement of the steering control.

[0079] In another embodiment provided by the application, after the Lagrange target function is iteratively updated by using the gradient descent method, the method further includes:

[0080] The iteratively updated dynamic vehicle state and the steering wheel control amount are constrained and protected by using a predetermined emergency collision avoidance control algorithm, so that the optimal and safe dynamic vehicle state and steering wheel control amount are obtained as the optimal steering control sequence for automatic steering control.

[0081] The emergency collision avoidance control algorithm of the automobile refers to an algorithm for actively intervening in the actuator to assist the driver in adjusting the motion trajectory of the automobile to achieve collision avoidance.

[0082] The automatic steering control method provided by the embodiment of the application guarantees the safety in the lane-changing steering control process by nesting the emergency collision avoidance control algorithm.

[0083] It should be noted that the target function in the above embodiment takes into account the lane-changing path tracking error, actuator energy consumption and steering additional fuel consumption increase.

[0084] Specifically, in addition to the additional fuel consumption term, energy consumption and path tracking accuracy, other steering control factors such as control amplitude, control speed and wear degree of the steering actuator are also considered.

[0085] The automatic steering control device provided by the application is described below, and the automatic steering control device described below can be referred to in conjunction with the automatic steering control method described above.

[0086] Figure 2 The structure block diagram of the automatic steering control device provided by the embodiment of the application is shown in FIG. Figure 2 The automatic steering control device includes a target function construction module 201 and an optimal steering control sequence solving module 202.

[0087] The target function construction module 201 is configured to construct a target function that takes into account the lane-changing path tracking error, actuator energy consumption and steering additional fuel consumption increase.

[0088] The steering additional fuel consumption increase is obtained based on the vehicle steering wheel angle and the vehicle speed.

[0089] In the module, firstly, the current steering wheel angle and vehicle speed information of the vehicle are acquired, and then the weighted combination of the steering wheel angle and the vehicle speed is formed into a polynomial of different orders or a linear superposition series of different terms according to the vehicle dynamics principle to represent the additional fuel consumption increase of steering, for example, the weighted combination of the steering wheel angle and the vehicle speed is formed into a quadratic function In the formula, δ is the steering wheel angle, v x is the vehicle speed, and w1 and w2 are weighting coefficients. The weighting coefficients in the above weighted combination process can be obtained according to the segmented linear function of the vehicle speed and the steering wheel angle, or can be obtained by polynomial fitting on the actual measurement data.

[0090] After the additional fuel consumption increase of steering represented by the vehicle steering wheel angle and the vehicle speed is obtained, a target function considering the lane changing path tracking error, the actuator energy consumption and the additional fuel consumption increase of steering is constructed. The additional fuel consumption increase of steering in the target function can be in the form of a quadratic function (i.e. In the formula, J is the target function, Pref is the reference path position, Q s is the additional fuel consumption increase of steering, and P s is the actuator energy consumption), or can be in the form of an absolute value (i.e. J = |P-Pref| + |P s | + |Q s |, in which J is the target function, Pref is the reference path position, Q s is the additional fuel consumption increase of steering, and P s is the actuator energy consumption). The target function considering the lane changing path tracking error, the actuator energy consumption and the additional fuel consumption increase of steering can be constructed through different forms of target functions.

[0091] It should be noted that, in the representation of the additional fuel consumption increase of steering, the longitudinal component of the front axle tire lateral force is used to approximate the increase of fuel consumption because the longitudinal component of the front axle tire lateral force is large during steering and is opposite to the direction of vehicle advancement. In addition, according to the vehicle dynamics principle, the increase of fuel consumption is closely related to the current steering wheel angle and the vehicle speed, so the combination of the steering wheel angle and the vehicle speed into a polynomial of different orders or a linear superposition series of different terms is used as the representation of the additional fuel consumption increase of steering.

[0092] In addition, the commonly used target function only considers the tracking effect of the reference path and the energy consumption factor of the steering actuator, and the target function in the present application adds the above-mentioned additional fuel consumption increase of steering factor, so as to construct a target function mainly considering the lane changing path tracking error, the actuator energy consumption and the increase of fuel consumption, and then the automatic steering control can be realized by considering the energy consumption, stability and fuel consumption.

[0093] The optimal steering control sequence solving module 202 is used to bring the constraint condition into the target function, and solve the optimal steering control sequence for steering control of the vehicle.

[0094] In the module, since the linearized steering dynamics constraint of the commercial vehicle and the safety distance constraint of the front and rear vehicles on the adjacent lane need to be considered, the fuel-saving lane-changing steering control problem is constructed as a constrained optimal control problem in a limited prediction time domain, that is, the above target function is constructed as the sum of the target functions at each time in the limited prediction time domain J 总 . Specifically, the prediction time domain T [1, 2, 3, …, k] is set, the target function at T1 is J1, the target function at T2 is J2, and so on, and the target function at Tk is J k . At this time, J 总 = J1+ J2+ J3+ …+ J k . Correspondingly, the constraint condition becomes the vehicle dynamics state relationship and the steering wheel angle cannot exceed the preset maximum steering angle δb.

[0095] According to the above vehicle dynamics state relationship and the constraint condition related to the steering wheel angle, the sum of the target functions J 总 can be directly optimized to obtain the optimal steering control sequence, or can be solved by simplifying the control problem to obtain the optimal steering control sequence. A series of optimal dynamic vehicle states and corresponding optimal steering control amounts are obtained by the above solving method, thereby forming the optimal steering control sequence and realizing automatic steering control of the vehicle.

[0096] The automatic steering control device provided by the embodiment of the application characterizes the steering additional fuel consumption increase by the steering wheel angle and the vehicle speed, constructs a target function considering the lane-changing path tracking error, actuator energy consumption and steering additional fuel consumption increase, and further solves the optimal steering control sequence, so that the steering wheel angle control can be optimized in the lane-changing steering control process of the commercial vehicle, and the effects of reduced driving resistance, reduced fuel consumption, reduced energy consumption and high path tracking accuracy are obtained.

[0097] Figure 3 is a schematic diagram of an entity structure of an electronic device provided by the embodiment of the application, as Figure 3As shown, the electronic device can include a processor 310, a communications interface 320, a memory 330, and a communications bus 340, wherein the processor 310, the communications interface 320, and the memory 330 complete mutual communication through the communications bus 340. The processor 310 can invoke a logical instruction in the memory 330 to execute an automatic steering control method, the automatic steering control method including: constructing a target function taking into account a lane-changing path tracking error, actuator energy consumption, and a steering additional fuel consumption increase; bringing a constraint condition into the target function to obtain an optimal steering control sequence for steering control of a vehicle; and wherein the steering additional fuel consumption increase is obtained based on a vehicle steering wheel angle and a vehicle speed.

[0098] In addition, the logical instruction in the memory 330 described above can be implemented in the form of a software functional unit and sold or used as an independent product, and can be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or part of the technical solutions can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a plurality of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the embodiments of the present application. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various program code storage media.

[0099] On the other hand, the present application also provides a computer program product, the computer program product including a computer program, the computer program being stored on a non-transitory computer-readable storage medium, and the computer program being executed by a processor, the computer being capable of executing an automatic steering control method provided by each of the methods, the automatic steering control method including: constructing a target function taking into account a lane-changing path tracking error, actuator energy consumption, and a steering additional fuel consumption increase; bringing a constraint condition into the target function to obtain an optimal steering control sequence for steering control of a vehicle; and wherein the steering additional fuel consumption increase is obtained based on a vehicle steering wheel angle and a vehicle speed.

[0100] In yet another aspect, the present application also provides a non-transitory computer readable storage medium having stored thereon a computer program, which, when executed by a processor, implements the automatic steering control method provided by the above method, the automatic steering control method comprising: constructing a target function taking into account a lane-changing path tracking error, actuator energy consumption, and an additional steering oil consumption increase; bringing a constraint condition into the target function to obtain an optimal steering control sequence for steering control of the vehicle; and wherein the additional steering oil consumption increase is obtained based on a vehicle steering wheel angle and a vehicle speed.

[0101] The device embodiments described above are merely illustrative, wherein the units shown as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, i.e., they can be located in one place, or distributed on multiple network units. Part or all of the modules can be selected to achieve the purpose of the embodiment according to actual needs. Those skilled in the art can understand and implement it without creative labor.

[0102] From the above description of the embodiments, those skilled in the art can clearly understand that the embodiments can be realized by means of software plus necessary universal hardware platforms, and of course, can also be realized by hardware. Based on such understanding, the above technical solutions, essentially or in other words, the part that contributes to the prior art, can be embodied in the form of a software product, which can be stored in a computer readable storage medium, such as a ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute the methods of the various embodiments or some parts of the embodiments.

[0103] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the above-mentioned embodiments of the present application have been described in detail, those skilled in the art should understand that they can still modify the technical solutions recorded in the above-mentioned embodiments, or make equivalent replacement for some technical features; and these modifications or replacements do not make the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. An automatic steering control method, characterized in that, include: Construct an objective function that takes into account lane change path tracking error, actuator energy consumption, and the increase in steering-related fuel consumption. Substituting the constraints into the objective function, the optimal steering control sequence is obtained and used for vehicle steering control. The increase in steering-related fuel consumption is obtained based on the vehicle's steering wheel angle and vehicle speed. The objective function is the objective function corresponding to the lane change steering control problem; Accordingly, substituting the constraints into the objective function to obtain the optimal steering control sequence for steering control of the vehicle includes: Based on the linearized steering dynamics constraints and the vehicle's safe distance constraints, the objective function corresponding to the lane-changing steering control problem is constructed as the objective function corresponding to the constrained optimal control problem in the finite prediction time domain. A first constraint and a second constraint are introduced; the first constraint is the vehicle dynamics state relationship; the second constraint is that the steering wheel angle cannot exceed the preset maximum angle δb. Based on the objective function, first constraint, and second constraint corresponding to the constrained optimal control problem, a Lagrange objective function considering the constraints is constructed. The Lagrange objective function is iteratively updated using the gradient descent method to calculate the optimal dynamic vehicle state and the optimal steering wheel control quantity, which are then used as the optimal steering control sequence.

2. The automatic steering control method according to claim 1, characterized in that, The increase in steering-related fuel consumption is derived from the vehicle's steering wheel angle and vehicle speed, and includes: The weights corresponding to the vehicle steering wheel angle and vehicle speed are obtained based on the vehicle dynamics model and vehicle acceleration, respectively. The additional fuel consumption due to steering is obtained by weighting the vehicle steering wheel angle, the weight corresponding to the vehicle steering wheel angle, the vehicle speed, and the weight corresponding to the vehicle speed.

3. The automatic steering control method according to claim 1, characterized in that, The objective function for constructing a system that considers lane-changing path tracking error, actuator energy consumption, and the increase in fuel consumption due to steering includes: The lane-change path tracking error is determined based on the difference between the vehicle's actual position and the reference path position. The sum of the squares of the lane change path tracking error, actuator energy consumption, and the increase in steering-related fuel consumption is used as the first objective function.

4. The automatic steering control method according to claim 1, characterized in that, The objective function for constructing a system that considers lane-changing path tracking error, actuator energy consumption, and the increase in fuel consumption due to steering includes: The lane-change path tracking error is determined based on the difference between the vehicle's actual position and the reference path position. The sum of the absolute values ​​of lane change path tracking error, actuator energy consumption, and the increase in steering-related fuel consumption is used as the second objective function.

5. The automatic steering control method according to claim 1, characterized in that, The objective function is constructed primarily based on lane change path tracking error, actuator energy consumption, and the increase in steering-related fuel consumption, supplemented by the control amplitude, control speed, and wear degree of the steering actuator.

6. The automatic steering control method according to claim 1, characterized in that, After iteratively updating the Lagrange objective function using gradient descent, the method further includes: The predetermined emergency collision avoidance control algorithm is used to constrain and protect the iteratively updated dynamic vehicle state and steering wheel control quantity, thereby obtaining the optimal dynamic vehicle state and the optimal steering wheel control quantity, which serve as the optimal steering control sequence.

7. An automatic steering control device, characterized in that, include: The objective function construction module is used to construct an objective function that takes into account lane change path tracking error, actuator energy consumption, and the increase in steering-related fuel consumption. The optimal steering control sequence solving module is used to input the constraints into the objective function and solve for the optimal steering control sequence, which is used to control the vehicle's steering. The increase in steering-related fuel consumption is obtained based on the vehicle's steering wheel angle and vehicle speed. The objective function is the objective function corresponding to the lane change steering control problem; Accordingly, the optimal steering control sequence solving module is used for: Based on the linearized steering dynamics constraints and the vehicle's safe distance constraints, the objective function corresponding to the lane-changing steering control problem is constructed as the objective function corresponding to the constrained optimal control problem in the finite prediction time domain. A first constraint and a second constraint are introduced; the first constraint is the vehicle dynamics state relationship; the second constraint is that the steering wheel angle cannot exceed the preset maximum angle δb. Based on the objective function, first constraint, and second constraint corresponding to the constrained optimal control problem, a Lagrange objective function considering the constraints is constructed. The Lagrange objective function is iteratively updated using the gradient descent method to calculate the optimal dynamic vehicle state and the optimal steering wheel control quantity, which are then used as the optimal steering control sequence.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the automatic steering control method as described in any one of claims 1 to 6.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the automatic steering control method as described in any one of claims 1 to 6.

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