Vehicle pivot steering control method and related device

Abstract

The invention discloses a vehicle in-situ steering control method and a related device. The method comprises the steps that the in-situ rotation direction and the target rotation angle set by a user are obtained; and an opening value applied to the accelerator pedal by the user is obtained, and the target yaw velocity is determined according to the opening value. The actual yaw velocity of the vehicle is obtained, the yaw velocity difference value is obtained according to the actual yaw velocity and the target yaw velocity, the total yaw torque of the whole vehicle is obtained with the yaw velocity difference value as the proportional-integral-differential control target, and the total yaw torque is equally divided to all wheels. And the distributed torque is corrected according to the rotation resistance of each wheel, and the actual torque of each wheel is obtained. The yaw velocity difference value serves as a control target for adjusting the driving force of the whole vehicle, precise control over the driving force of the vehicle is achieved, and then stable in-situ steering of the vehicle is assisted. And the vehicle is controlled to rotate to the target rotating angle in situ according to the actual torque and the in-situ rotating direction, so that the safety and comfort in the in-situ steering process can be improved.

Description

Technical Field

[0001] The present application relates to the field of computers, and in particular, to a method and related device for controlling in-situ steering of a vehicle. Background Art

[0002] With the rapid development of the automotive industry, vehicle-related control algorithms are also developing rapidly, such as in-situ steering control algorithms. In-situ steering control of a vehicle is an important scenario for vehicle applications. In-situ steering of a vehicle requires providing sufficient driving force to the vehicle to make the vehicle turn in the direction required by the user. However, there is a problem of insufficient driving force control in current in-situ steering of vehicles, which cannot achieve smooth steering of the vehicle, reducing the safety and comfort of the vehicle during in-situ steering.

[0003] Therefore, there is an urgent need for a method for controlling in-situ steering of a vehicle. Summary of the Invention

[0004] The present application provides a method and related device for controlling in-situ steering of a vehicle, which can achieve precise control of the driving force of the vehicle, realize smooth in-situ steering of the vehicle, and improve the safety and comfort during in-situ steering.

[0005] The present application provides a method for controlling in-situ steering of a vehicle, the method comprising:

[0006] Obtaining the in-situ rotation direction and the target rotation angle set by the user;

[0007] Obtaining the opening value applied by the user to the accelerator pedal, and determining the target yaw rate according to the opening value;

[0008] Obtaining the actual yaw rate of the vehicle, and obtaining a yaw rate difference according to the actual yaw rate and the target yaw rate;

[0009] Taking the yaw rate difference as a proportional-integral-derivative (PID) control target to obtain the total yaw torque of the vehicle, and equally dividing the total yaw torque according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel;

[0010] Controlling the vehicle to rotate in-situ to the target rotation angle according to the actual torque and the in-situ rotation direction.

[0011] Optionally, the taking the yaw rate difference as a proportional-integral-derivative (PID) control target to obtain the total yaw torque of the vehicle, and equally dividing the total yaw torque according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel includes:

[0012] After performing proportional processing, differential processing, and integral processing on the yaw rate difference respectively, add the results of the proportional processing, the results of the differential processing, and the results of the integral processing to obtain the motor closed-loop control torque vector;

[0013] Obtain the total yaw torque of the vehicle according to the motor closed-loop control torque vector, and evenly divide the total yaw torque according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel.

[0014] Optionally, the method further includes:

[0015] Obtain the in-situ steering feedforward torque;

[0016] The obtaining the total yaw torque of the vehicle according to the motor closed-loop control torque vector, and evenly dividing the total yaw torque according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel includes:

[0017] Perform an addition process on the motor closed-loop control torque vector and the in-situ steering feedforward torque to obtain the total yaw torque of the vehicle;

[0018] Evenly divide the total yaw torque according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel.

[0019] Optionally, the vehicle includes 4 wheels, and the torque of the motor corresponding to each wheel is the same;

[0020] The evenly dividing the total yaw torque according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel includes:

[0021] Evenly divide the total yaw torque to determine the actual torque provided by the motor corresponding to each of the 4 wheels.

[0022] Optionally, the obtaining the in-situ steering feedforward torque includes:

[0023] The in-situ steering feedforward torque is equal to the sum of the slip resistance torque and the rolling resistance torque.

[0024] Optionally, the method further includes:

[0025] Determine the direction of the torque provided by the motor corresponding to each wheel according to the in-situ rotation direction.

[0026] Optionally, before obtaining the opening change value applied by the user to the accelerator pedal, the method further includes:

[0027] Judge whether the distance of the obstacle around the vehicle is greater than the distance threshold;

[0028] If it is greater, lock the steering wheel and lock the steering angle of the wheel parallel to the front direction of the vehicle.

[0029] Optionally, before obtaining the opening change value applied by the user to the accelerator pedal, the method further includes:

[0030] Obtaining the current torque provided by the motor corresponding to each wheel;

[0031] Judging whether the current torque is greater than the static friction resistance torque threshold or judging whether the wheel speed of the wheel is greater than 0. If it is greater, execute the step of obtaining the opening change value applied by the user to the accelerator pedal.

[0032] The present application provides a vehicle in-situ steering control device, and the device includes:

[0033] A first obtaining unit, configured to obtain the in-situ rotation direction and the target rotation angle set by the user;

[0034] A second obtaining unit, configured to obtain the opening value applied by the user to the accelerator pedal, and determine the target yaw angular velocity according to the opening value;

[0035] A third obtaining unit, configured to obtain the actual yaw angular velocity of the vehicle, and obtain a yaw angular velocity difference according to the actual yaw angular velocity and the target yaw angular velocity;

[0036] A control unit, configured to use the yaw angular velocity difference as a proportional-integral-derivative (PID) control target to obtain the total yaw torque of the vehicle, and evenly divide the total yaw torque according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel;

[0037] A rotation unit, configured to control the vehicle to rotate in-situ to the target rotation angle according to the actual torque and the in-situ rotation direction.

[0038] The present application provides a computer-readable storage medium, including instructions, which when running on a computer, cause the computer to execute the method described in any one of the above.

[0039] The present application provides a method for controlling in-situ steering of a vehicle. The method includes: obtaining the in-situ rotation direction and the target rotation angle set by the user, so that the vehicle can be driven to perform in-situ steering according to the in-situ rotation direction and the target rotation angle. Obtaining the opening value applied by the user to the accelerator pedal, and determining the target yaw rate according to the opening value. Obtaining the actual yaw rate of the vehicle, and obtaining the yaw rate difference according to the actual yaw rate and the target yaw rate. In this way, subsequently, the yaw rate difference can be used as the proportional-integral-derivative (PID) control target to obtain the total yaw torque of the vehicle. The total yaw torque is evenly divided according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel. That is, by using the yaw rate difference as the control target for adjusting the driving force of the whole vehicle, the precise control of the driving force of the vehicle is realized, and then the smooth in-situ steering of the vehicle is assisted. Controlling the vehicle to rotate in-situ to the target rotation angle according to the actual torque and the in-situ rotation direction can improve the safety and comfort during the in-situ steering process. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0041] Figure 1 It is a flowchart of a method for controlling in-situ steering of a vehicle provided by an embodiment of the present application;

[0042] Figure 2 It is a schematic diagram of the forces acting on a vehicle during in-situ steering provided by an embodiment of the present application;

[0043] Figure 3 It is a logic diagram of in-situ steering of a vehicle provided by an embodiment of the present application;

[0044] Figure 4 It is a structural block diagram of a device for controlling in-situ steering of a vehicle provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] In order to enable those skilled in the art to better understand the solution of the present application, the following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0046] With the rapid development of the automotive industry, vehicle-related control algorithms are also developing rapidly, such as in-place steering control algorithms. In-place steering control of a vehicle is an important scenario for vehicle applications. In-place steering of a vehicle requires providing sufficient driving force to the vehicle to turn the vehicle in the direction demanded by the user. However, there is currently a problem of insufficient driving force control in vehicle in-place steering, which cannot achieve smooth steering of the vehicle and reduces the safety and comfort of the vehicle during in-place steering.

[0047] Especially when an electric vehicle steers in place, it requires the motors corresponding to each wheel of the vehicle to provide driving torque. However, currently, the torque cannot be accurately controlled, and thus the driving force of the vehicle cannot be accurately controlled.

[0048] Therefore, there is an urgent need for a vehicle in-place steering control method now.

[0049] Based on this, the present application provides a vehicle in-place steering control method. The method includes: obtaining the in-place rotation direction and the target rotation angle set by the user, so that the vehicle can be driven to steer in place according to the in-place rotation direction and the target rotation angle. Obtaining the opening value applied by the user to the accelerator pedal, and determining the target yaw rate according to the opening value. Obtaining the actual yaw rate of the vehicle, and obtaining the yaw rate difference according to the actual yaw rate and the target yaw rate. In this way, subsequently, the yaw rate difference can be used as the proportional-integral-derivative (PID) control target, and the actual torque provided by the motor corresponding to each wheel can be obtained respectively. That is, by using the yaw rate difference as the adjustment target for the vehicle's driving force control, the accurate control of the vehicle's driving force can be achieved, and then the smooth in-place steering of the vehicle can be assisted. Controlling the vehicle to rotate in place to the target rotation angle according to the actual torque and the in-place rotation direction can improve the safety and comfort during in-place steering.

[0050] To better understand the technical solution and technical effect of the present application, specific embodiments will be described in detail below with reference to the accompanying drawings.

[0051] See Figure 1 , which is a flowchart of a vehicle in-place steering control method provided by an embodiment of the present application.

[0052] The vehicle in-place steering control method provided by this embodiment includes the following steps:

[0053] S101, obtaining the in-place rotation direction and the target rotation angle set by the user.

[0054] In the embodiment of the present application, when the user wants the vehicle to steer in place, the user can click on the screen of the vehicle intelligent driving system to trigger and activate the in-place steering mode, so that the vehicle enters the preparation process for in-place steering.

[0055] The user can set the in-place turning direction and the target turning angle through the screen of the intelligent driving system. The in-place turning direction includes the clockwise direction and the counterclockwise direction. The target turning angle is the angle that the vehicle rotates around the center of the vehicle during in-place turning.

[0056] In the embodiments of the present application, for different in-place turning directions of the vehicle, the directions of the torques provided to the motors corresponding to each wheel are different. That is, the direction of the torque provided to the motor corresponding to each wheel can be determined according to the in-place turning direction, so that in-place turning can be carried out smoothly.

[0057] As an example, when the in-place turning direction is the counterclockwise direction, refer to Figure 2 As shown, the vehicle includes 4 wheels. Figure 2 The upper part represents the head direction of the vehicle. Figure 2 The 2 wheels above are the front-side wheels. Figure 2 The lower part represents the tail direction of the vehicle. Figure 2 The 2 wheels below are the rear-side wheels. Then, when the vehicle turns in place in the counterclockwise direction, the center of the vehicle is used as the in-place turning center. When the in-place turning direction of the vehicle is the counterclockwise direction, Figure 2 The 2 wheels on the left are the inner wheels. Figure 2 The 2 wheels on the right are the outer wheels. At this time, a positive torque can be provided to the front outer wheels and the rear outer wheels of the vehicle, and a reverse torque can be provided to the front inner wheels and the rear inner wheels of the vehicle. Among them, the positive torque is the direction in which the tail of the vehicle faces the head, that is, the forward torque. Thus, when the in-place turning direction of the vehicle is the counterclockwise direction, Figure 2 The 2 wheels on the left have a forward torque. Figure 2 The 2 wheels on the right have a backward torque.

[0058] As another example, when the in-place turning direction is the clockwise direction, still a positive torque is provided to the front outer wheels and the rear outer wheels of the vehicle, and a reverse torque is provided to the front inner wheels and the rear inner wheels of the vehicle. Among them, the positive torque is the direction in which the tail of the vehicle faces the head, that is, the forward torque. However, at this time, the front outer wheels and the rear outer wheels of the vehicle are Figure 2 The 2 wheels on the right, and the front inner wheels and the rear inner wheels of the vehicle are Figure 2 The 2 wheels on the left.

[0059] It can be seen that when the torque directions on both sides of the vehicle are different, the speed directions of the wheels on both sides of the vehicle are opposite. If the speed magnitudes on both sides of the vehicle are equal, in-place turning of the vehicle can be achieved.

[0060] In the embodiments of the present application, before the vehicle turns in place, it can be determined whether the vehicle meets the in-place turning conditions. The following is a specific introduction:

[0061] It is possible to determine whether the distance to the obstacle around the vehicle is greater than the distance threshold, that is, to determine whether the distance between the obstacle around the vehicle and the vehicle meets the requirement. If the distance to the obstacle around the vehicle is not greater than the distance threshold, it means that the distance between the vehicle and the obstacle is too close and the vehicle may not be able to perform in-place steering. If the distance to the obstacle around the vehicle is greater than the distance threshold, it means that the obstacle does not affect the in-place steering of the vehicle.

[0062] It is possible to determine whether the vehicle speed is 0, that is, to determine whether the vehicle is stationary. If the vehicle speed is not 0, the vehicle cannot perform in-place steering. If the vehicle speed is 0, it means that the vehicle speed meets the requirement for in-place steering.

[0063] It is possible to determine whether the ground is flat, that is, to judge the ground condition for the vehicle to perform in-place steering. If the ground is not flat, the vehicle cannot perform in-place steering. If the ground is flat, it means that the ground condition meets the requirement for in-place steering.

[0064] It is possible to determine whether the current accelerator pedal and the current brake pedal are at an opening of 0. If the opening is not 0, the vehicle cannot perform in-place steering. If the opening is 0, it meets the requirement for in-place steering.

[0065] After the above conditions are met, the steering wheel can be locked and the steering angle of the wheels can be locked parallel to the front direction of the vehicle, that is, the steering angle of the steering wheel is set to 0 and the steering angle of the wheels is set to 0. Then, according to the in-place rotation direction and the target steering angle, the vehicle starts to perform in-place steering.

[0066] S102. Obtain the opening value applied by the user to the accelerator pedal, and determine the target yaw rate according to the opening value.

[0067] In the embodiment of the present application, after the vehicle starts in-place steering, the user can apply a certain opening to the accelerator pedal, that is, the opening of the accelerator pedal is greater than the threshold, so as to drive the vehicle to start in-place rotation. The vehicle in-place steering control can be divided into two stages: the static friction overcoming stage and the dynamic friction overcoming stage, as shown in Figure 3 As shown. The vehicle does not rotate in the static friction overcoming stage, and the vehicle rotates to the target steering angle in the dynamic friction overcoming stage.

[0068] In the stage of overcoming static friction, a static friction resistance torque threshold can be preset. When the torque provided by the motor corresponding to each wheel is greater than the static friction resistance torque threshold, it means that the driving force of the vehicle is greater than the static friction force, and the vehicle has a vehicle speed and can turn to the target angle. Therefore, when the vehicle enters the in-situ steering mode, the user can apply a certain opening degree to the accelerator pedal to utilize the torque provided by the motor. At this time, the opening degree of the brake pedal is 0. The torque provided by the motor corresponding to each wheel is theoretically the same and gradually linearly increases with time to utilize the torque provided by the motor to overcome the static friction force of the vehicle. Then, the current torque provided by the motor corresponding to each wheel is obtained, and it is judged whether the current torque is greater than the static friction resistance torque threshold or whether the wheel speed of the wheel is greater than 0. If the current torque is greater than the static friction resistance torque threshold or the wheel speed of the wheel is greater than 0, it means that the vehicle already has a vehicle speed and has entered the stage of overcoming dynamic friction, and then the vehicle control steps in the stage of overcoming dynamic friction are executed.

[0069] In practical applications, the static friction force received by the vehicle is greater than the dynamic friction force received by the vehicle. Therefore, when the current torque is greater than the static friction resistance torque threshold, it means that the stage of overcoming dynamic friction has been entered. To achieve smooth in-situ steering of the vehicle, the torque of the motor can be reduced at this time. Specifically, it can be linearly reduced to a fixed value according to time, so as to control the in-situ steering of the vehicle based on this fixed value in the stage of overcoming dynamic friction. Among them, the fixed value can be the in-situ steering feedforward torque. Therefore, the in-situ steering feedforward torque can be obtained to achieve the control of in-situ steering.

[0070] As a possible implementation method, assume that the vehicle includes 4 wheels, and the loads of the 4 wheels are equal, all being G / 4, where G is the vehicle weight. Refer to Figure 2 As shown, the maximum adhesion force of each wheel is equal, that is is the adhesion coefficient. The rolling resistance of each wheel is equal, that is Ff1 = Ff2 = Ff3 = Ff4 = 1 / 4Gf, where f is the rolling resistance coefficient. The lateral sliding resistance of each wheel is equal, Fμ1 = Fμ2 = Fμ3 = Fμ4 = 1 / 4Gμ, where μ is the sliding coefficient. The driving torque of the vehicle during in-situ steering ΣMt = 4Mt1 = 2BFt1. The maximum adhesion torque received by the vehicle B is the wheelbase. The sliding resistance torque received by the vehicle ΣMμ = 4Mμ1 = 2LFμ1, where L is the wheelbase. The rolling resistance torque received by the vehicle ΣMf = 4Mf1 = 2BFf1. To achieve in-situ steering, it must be satisfied that the maximum adhesion torque of the vehicle is greater than or equal to the driving torque of the vehicle ΣMt, and the driving torque of the vehicle ΣMt is equal to the sum of the sliding resistance torque ΣMμ and the rolling resistance torque ΣMf, that is Among them, assuming that the driving torque received by each wheel is Ft when the yaw rate ω during in-place turning remains stable, and the torques provided by the motors corresponding to each wheel are the same, ΣMt = ΣMμ + ΣMf can be expressed as 2BFt1 = 2LFμ1 + 2BFf1 = 2×(L×1 / 4×Gμ + B×1 / 4×Gf), and further expressed as Ft1 = 2×(L×1 / 4×Gμ + B×1 / 4×Gf) / (2B). It should be noted that the vehicle driving torque ΣMt during in-place turning is equal to the in-place turning feedforward torque MzFF, that is, the in-place turning feedforward torque MzFF is equal to the sum of the slip resistance torque ΣMμ and the rolling resistance torque ΣMf.

[0071] In the embodiments of the present application, simply using the in-place turning feedforward torque is not sufficient to achieve stable control of in-place turning. The torque of the motor can be controlled in a closed loop to achieve precise control of in-place turning. To implement closed-loop control of the motor torque, the opening value applied by the user to the accelerator pedal can be obtained, and then the target yaw rate can be determined according to the opening value, that is, the opening degree of the accelerator pedal is obtained to obtain the target yaw rate Target yaw rate. That is, the target yaw rate changes with the opening degree of the accelerator pedal within a certain limit.

[0072] S103, obtain the actual yaw rate of the vehicle, and obtain the yaw rate difference according to the actual yaw rate and the target yaw rate.

[0073] In the embodiments of the present application, the actual yaw rate Yaw rate of the vehicle can be obtained through the sensors provided on the vehicle, and then the yaw rate difference YRerror is obtained according to the actual yaw rate and the target yaw rate.

[0074] Specifically, the yaw rate difference YRerror is the value obtained by subtracting the target yaw rate from the actual yaw rate, that is, YRerror = Yaw rate - Target yaw rate.

[0075] S104, use the yaw rate difference as the proportional-integral-differential (PID) control target to obtain the total yaw torque of the vehicle, and evenly divide the total yaw torque according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel.

[0076] In the embodiments of the present application, on the basis of the in-place turning feedforward torque, using the yaw rate difference as the proportional-integral-differential (PID) control target to obtain the total yaw torque of the vehicle, and evenly dividing the total yaw torque according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel, so that the closed-loop control of the motor torque can be realized, and then the precise control of the yaw rate of the vehicle during in-place turning can be realized, thereby realizing the precise control of in-place turning and achieving stable and safe in-place turning.

[0077] Specifically, after performing proportional processing, differential processing, and integral processing on the yaw rate difference respectively, the results of proportional processing, differential processing, and integral processing are added together to obtain the motor closed-loop control torque vector MzFB of multiple motors. That is, MzFB = Kp(YReror) + Kd(YRerror) / dt + Ki×∫(YRerror)dt, where Kp is the proportional feedback gain, Kd is the differential gain, and Ki is the integral gain.

[0078] After obtaining the motor closed-loop control torque vector of multiple motors, the total yaw torque of the vehicle can be obtained according to the motor closed-loop control torque vector, and the total yaw torque is evenly divided according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel. For example, the motor closed-loop control torque vector and the in-situ steering feedforward torque can be added together to obtain the total yaw torque of the vehicle, and then the actual torque provided by the motor corresponding to each wheel is determined according to the total yaw torque of the vehicle. Specifically, the total yaw torque can be evenly divided according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel.

[0079] As a possible implementation, the vehicle includes 4 wheels, and the torque of the motor corresponding to each wheel is the same. In this way, by evenly dividing the total yaw torque of the vehicle, the actual torque provided by the motor corresponding to each of the 4 wheels and the actual driving force provided by the motor can be determined.

[0080] As an example, the total yaw torque or the total driving force of the vehicle is Mz = MzFF + MzFB = B / 2(Ffi + Fri + Ffo + Fro), where Ffi is the driving force of the front inner wheel, Fri is the driving force of the rear inner wheel, Ffo is the driving force of the front outer wheel, and Fro is the driving force of the rear outer wheel.

[0081] In practical applications, after evenly dividing the total yaw torque to each wheel, the distributed torque can be adjusted according to the rotational resistance of each wheel, and then the actual torque of each wheel can be obtained. This can improve the accuracy of the actual torque, thereby further improving the safety and comfort of in-situ steering.

[0082] S105, Control the vehicle to rotate in place to the target angle according to the actual torque and the in-situ rotation direction.

[0083] In the embodiments of the present application, after obtaining the actual torque of each motor, the vehicle can be controlled to rotate in place at a certain yaw rate to the target angle according to the actual torque and the in-situ rotation direction.

[0084] Specifically, refer to Figure 3As shown, the actual rotation angle Yaw can be obtained by integrating the actual yaw rate. It is determined whether the actual rotation angle Yaw is greater than the target rotation angle. If the actual rotation angle Yaw is not greater than the target rotation angle, the process of continuously executing the closed-loop control of the motor torque to control the yaw rate is continued. If the actual rotation angle Yaw is greater than the target rotation angle, the torque of the motor is set to 0, indicating that the in-place steering is completed.

[0085] In practical applications, during the process of closed-loop controlling the motor torque, it can also be determined whether the opening value of the brake pedal is greater than the threshold value. If it is greater, the torque of the motor is set to 0, indicating exiting the in-place steering.

[0086] This application provides a vehicle in-place steering control method. The method includes: obtaining the in-place rotation direction and the target rotation angle set by the user, so that the vehicle can be driven to perform in-place steering according to the in-place rotation direction and the target rotation angle. Obtaining the opening value applied by the user to the accelerator pedal, and determining the target yaw rate according to the opening value. Obtaining the actual yaw rate of the vehicle, and obtaining the yaw rate difference according to the actual yaw rate and the target yaw rate. In this way, subsequently, the yaw rate difference can be used as the proportional-integral-derivative PID control target to obtain the total yaw torque of the vehicle, and the total yaw torque is evenly divided according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel, that is, by using the yaw rate difference as the adjustment target of the vehicle driving force control, the precise control of the vehicle driving force is realized, and then the smooth in-place steering of the vehicle is assisted. Controlling the vehicle to rotate in place to the target rotation angle according to the actual torque and the in-place rotation direction can improve the safety and comfort during the in-place steering process.

[0087] Based on the vehicle in-place steering control method provided in the above embodiments, the embodiments of this application also provide a vehicle in-place steering control device. The working principle will be described in detail below with reference to the drawings.

[0088] See Figure 4 , this figure is a structural block diagram of a vehicle in-place steering control device provided by an embodiment of this application.

[0089] The vehicle in-place steering control device 200 provided in this embodiment includes:

[0090] A first acquisition unit 210, configured to acquire the in-place rotation direction and the target rotation angle set by the user;

[0091] A second acquisition unit 220, configured to acquire the opening value applied by the user to the accelerator pedal, and determine the target yaw rate according to the opening value;

[0092] A third acquisition unit 230, configured to acquire the actual yaw rate of the vehicle, and obtain the yaw rate difference according to the actual yaw rate and the target yaw rate;

[0093] A control unit 240, configured to use the yaw rate difference as a proportional-integral-derivative (PID) control target to obtain the total yaw torque of the vehicle, and evenly divide the total yaw torque according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel;

[0094] A rotation unit 250, configured to control the vehicle to rotate in place to the target angle according to the actual torque and the in-place rotation direction.

[0095] Optionally, the third acquisition unit 230 is configured to:

[0096] Perform proportional processing, derivative processing, and integral processing on the yaw rate difference respectively, and then add the results of the proportional processing, the results of the derivative processing, and the results of the integral processing to obtain a motor closed-loop control torque vector;

[0097] Obtain the total yaw torque of the vehicle according to the motor closed-loop control torque vector, and evenly divide the total yaw torque according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel.

[0098] Optionally, the device further includes a fourth acquisition unit, configured to:

[0099] Obtain an in-place rotation feedforward torque;

[0100] The third acquisition unit 230 is configured to:

[0101] Perform an addition process on the motor closed-loop control torque vector and the in-place rotation feedforward torque to obtain the total yaw torque of the vehicle;

[0102] Evenly divide the total yaw torque according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel.

[0103] Optionally, the vehicle includes 4 wheels, and the torques of the motors corresponding to each wheel are the same;

[0104] The third acquisition unit 230 is configured to:

[0105] Evenly divide the total yaw torque to determine the actual torque provided by the motor corresponding to each of the 4 wheels.

[0106] Optionally, the fourth acquisition unit is configured to:

[0107] The in-place rotation feedforward torque is equal to the sum of the slip resistance torque and the rolling resistance torque.

[0108] Optionally, the device further includes a determination unit, configured to:

[0109] Determine the direction of the torque provided by the motor corresponding to each wheel according to the in-situ rotation direction.

[0110] Optionally, before obtaining the opening change value applied by the user to the accelerator pedal, the device further includes a judgment unit for:

[0111] Judge whether the distance of the obstacle around the vehicle is greater than the distance threshold;

[0112] If it is greater, lock the steering wheel and lock the steering angle of the wheel parallel to the front direction of the vehicle.

[0113] Optionally, before obtaining the opening change value applied by the user to the accelerator pedal, the device further includes a fifth acquisition unit for:

[0114] Obtain the current torque provided by the motor corresponding to each wheel;

[0115] Judge whether the current torque is greater than the static friction resistance torque threshold or judge whether the wheel speed of the wheel is greater than 0. If it is greater, execute the step of obtaining the opening change value applied by the user to the accelerator pedal.

[0116] The embodiment of the present application also provides a computer-readable storage medium for storing program codes, and the program codes are used to execute any one of the methods in the foregoing various embodiments.

[0117] In the context of the present application, a machine-readable medium may be a tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatuses, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media would include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0118] It should be noted that the computer-readable medium described above in this application can be a computer-readable signal medium, a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples of a computer-readable storage medium can include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this application, a computer-readable storage medium can be any tangible medium that contains or stores a program, and this program can be used by or in combination with an instruction execution system, apparatus, or device. And in this application, a computer-readable signal medium can include a data signal propagated in a baseband or as part of a carrier wave, which carries computer-readable program code. Such a propagated data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, and this computer-readable signal medium can send, propagate, or transmit a program for use by or in combination with an instruction execution system, apparatus, or device. The program code contained on a computer-readable medium can be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (radio frequency), etc., or any suitable combination of the above.

[0119] It should be noted that those of ordinary skill in the art can understand that to implement all or part of the processes in the above method embodiments, it can be completed by instructing relevant hardware through a computer program. The program can be stored in a computer-readable storage medium, and when the program is executed, it can include the processes of the above method embodiments. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), etc.

[0120] Computer program code for performing the operations of this application can be written in one or more programming languages or combinations thereof. The above-mentioned programming languages include, but are not limited to, object-oriented programming languages such as Java, Smalltalk, C++, and also include conventional procedural programming languages such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, executed as an independent software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computer (for example, by using an Internet service provider to connect through the Internet).

[0121] Each embodiment in this specification is described in a progressive manner. For the same or similar parts among the embodiments, reference can be made to each other. The key point of each embodiment is to illustrate the differences from other embodiments. In particular, for the device embodiments, since they are basically similar to the method embodiments, the description is relatively simple. For the relevant parts, reference can be made to the partial description of the method embodiments. The device embodiments described above are only illustrative. The units and modules described as separate components may or may not be physically separated. In addition, some or all of the units and modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. Those of ordinary skill in the art can understand and implement it without creative efforts.

[0122] The above is only the preferred embodiment of this application. Although this application has been disclosed above with preferred embodiments, it is not intended to limit this application. Any person skilled in the art can make many possible changes and modifications to the technical solution of this application by using the methods and technical contents disclosed above, or modify it into equivalent embodiments with equivalent changes. Therefore, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of this application without departing from the technical solution of this application still fall within the scope of the protection of the technical solution of this application.

Claims

1. A vehicle on-site steering control method, characterized in that: The method comprises: Get the in-situ rotation direction and target angle set by the user; Acquiring an opening value of an accelerator pedal applied by a user, and determining a target yaw angular velocity according to the opening value; Acquiring an actual yaw rate of the vehicle, and obtaining a yaw rate difference according to the actual yaw rate and the target yaw rate; The yaw rate difference is used as a proportional-integral-differential PID control target to obtain a total yaw torque of the vehicle, and the total yaw torque is evenly divided according to the number of wheels to obtain an actual torque provided by a motor corresponding to each wheel; The vehicle is controlled to rotate in situ to the target rotation angle according to the actual torque and the in situ rotation direction.

2. The method according to claim 1, characterized in that The yaw rate difference is used as the proportional-integral-differential PID control target to obtain the total yaw torque of the vehicle, and the total yaw torque is evenly divided according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel, including: After respectively performing proportional processing, differential processing and integral processing on the yaw angular velocity difference, the results of the proportional processing, the results of the differential processing and the results of the integral processing are added together to obtain a motor closed-loop control torque vector; The total yaw torque of the vehicle is obtained according to the motor closed-loop control torque vector, and the total yaw torque is evenly divided according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel.

3. The method according to claim 2, characterized in that The method further comprises: Get the in-situ steering feedforward torque; The total yaw torque of the vehicle is obtained according to the motor closed-loop control torque vector, and the total yaw torque is evenly divided according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel, which includes: Adding the motor closed-loop control torque vector and the in-situ steering feedforward torque to obtain a total yaw torque of the vehicle; The total yaw torque is evenly divided according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel.

4. The method according to claim 3, characterized in that The vehicle includes four wheels, and the torque of the motor corresponding to each wheel is the same; The step of equally dividing the total yaw torque according to the number of wheels to obtain the actual torque provided by the motor corresponding to each wheel comprises: The total yaw torque is evenly divided to determine the actual torque provided by the motor corresponding to each of the four wheels.

5. The method according to claim 3, characterized in that: The obtaining of the in-situ steering feedforward torque comprises: The in-situ steering feed-forward torque is equal to the sum of the slip resistance torque and the rolling resistance torque.

6. The method according to claim 5, characterized in that The method further comprises: The direction of the torque provided by the motor corresponding to each wheel is determined according to the in-situ rotation direction.

7. The method according to claim 1, characterized in that Before obtaining the opening change value applied by the user to the accelerator pedal, the method further includes: Determining whether the distance of obstacles around the vehicle is greater than a distance threshold; If it is greater than, the steering wheel is locked and the steering angle of the wheel is locked parallel to the front direction of the vehicle.

8. The method according to claim 1, characterized in that Before obtaining the opening change value applied by the user to the accelerator pedal, the method further includes: Get the current torque provided by the motor corresponding to each wheel; Determine whether the current torque is greater than the static friction resistance torque threshold or determine whether the wheel speed is greater than 0. If so, execute the step of obtaining the opening change value applied by the user to the accelerator pedal.

9. A vehicle in-situ steering control device, characterized in that: The device comprises: A first acquisition unit is used to acquire the in-situ rotation direction and target rotation angle set by the user; a second acquisition unit, configured to acquire an opening value applied by a user to the accelerator pedal, and determine a target yaw angular velocity according to the opening value; a third acquisition unit, configured to acquire an actual yaw rate of the vehicle, and obtain a yaw rate difference according to the actual yaw rate and the target yaw rate; a control unit, configured to use the yaw rate difference as a proportional-integral-differential PID control target to obtain a total yaw torque of the vehicle, and evenly divide the total yaw torque according to the number of wheels to obtain an actual torque provided by a motor corresponding to each wheel; The rotation unit is used to control the vehicle to rotate in situ to the target angle according to the actual torque and the in situ rotation direction.

10. A computer-readable storage medium, characterized in that: The method comprises instructions which, when executed on a computer, cause the computer to execute the method according to any one of claims 1 to 9.

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