Control method and device for a vehicle steering system

Abstract

The application provides a control method and device of a vehicle steering system, the method comprising: determining a vehicle state according to operation data of the vehicle; when it is determined that the vehicle state is a steering obstacle state, setting a preset safety protection angle as a target angle of a steering execution mechanism, and controlling the steering execution mechanism to rotate to the target angle at a first angle change speed, the safety protection angle being determined according to a current protection threshold of an execution motor, the first angle change speed being a change speed of an actual angle of a pinion gear of the steering execution mechanism, and the first angle change speed being not greater than a preset change speed threshold; and when it is determined that the vehicle state is an out-of-steering-obstacle state, controlling the target angle to change from the safety protection angle to an instruction steering angle according to a duration, the instruction steering angle being related to a target steering angle of the vehicle, and the duration being a duration for which the vehicle is in the out-of-steering-obstacle state.

Description

Technical Field

[0001] This invention relates to the field of vehicle control technology, and in particular to a control method and apparatus for a vehicle steering system. Background Technology

[0002] Steer-by-wire is a new type of automotive steering system. In this system, the rotation of the vehicle's steering wheels is controlled by an actuator motor. The controller only needs to provide steering commands to the actuator motor via a bus to control the vehicle's steering.

[0003] When a vehicle is turning, it may encounter a steering obstacle. When a vehicle with a steer-by-wire system is in this situation, the actuator motor may experience significant current fluctuations due to the steering wheel getting stuck, which can negatively impact the stability of the steer-by-wire system.

[0004] Therefore, ensuring the stability of the steer-by-wire system under obstacle-prone steering conditions has become an urgent problem to be solved in the field of steer-by-wire systems. Summary of the Invention

[0005] To address the shortcomings of the prior art, the present invention provides a control method and apparatus for a vehicle steering system to improve the stability and smoothness of the steer-by-wire system under obstacle-prone steering conditions.

[0006] The first aspect of this application provides a control method for a vehicle steering system, comprising:

[0007] Determine the vehicle status based on the vehicle's operating data;

[0008] When the vehicle is determined to be in a steering obstacle encounter state, a preset safety protection angle is set as the target angle of the steering actuator, and the steering actuator is controlled to rotate to the target angle at a first angle change speed. The safety protection angle is determined according to the current protection threshold of the actuator motor. The first angle change speed is the actual angle change speed of the pinion gear of the steering actuator, and the first angle change speed is not greater than the preset change speed threshold.

[0009] When the vehicle is determined to be in an obstacle-encountering state, the target angle is controlled to change from the safety protection angle to the commanded steering angle according to the duration. The commanded steering angle is related to the vehicle's target steering angle, and the duration is the length of time the vehicle is in the obstacle-encountering state.

[0010] Optionally, determining the vehicle status based on the vehicle's operating data includes:

[0011] The vehicle status is determined based on the real-time current and speed data of the actuator motor, as well as the vehicle's obstacle warning signal.

[0012] Optionally, determining the vehicle status based on the real-time current data and real-time speed data of the actuator motor, as well as the vehicle's obstacle detection signal, includes:

[0013] If, within a preset first time period, the current value corresponding to the real-time current data is greater than the first current threshold and the speed value corresponding to the real-time speed data is less than the first speed threshold, the vehicle state is determined to be a steering obstacle encounter state, and the vehicle obstacle encounter signal is set to a high bit.

[0014] When the obstacle encounter signal switches from a high position to a low position, the vehicle status is determined to be an obstacle encounter state when turning out.

[0015] Optional, also includes:

[0016] When the vehicle is determined to be in a turning obstacle encounter state, the obstacle encounter direction is determined based on the current direction corresponding to the real-time current data.

[0017] Optionally, the step of controlling the target angle to change from the safety protection angle to the command steering angle based on the duration includes:

[0018] Determine a first coefficient and a second coefficient that are linearly related to the duration, wherein the first coefficient decreases from 1 to 0 as the duration increases, and the second coefficient increases from 0 to 1 as the duration increases;

[0019] The target angle is obtained by summing the product of the first coefficient and the safety protection angle, and the product of the second coefficient and the command steering angle.

[0020] Optional, also includes:

[0021] When the vehicle is determined to be in an obstacle-free state, the command steering angle is set to the target angle of the steering actuator, and the steering actuator is controlled to rotate to the target angle.

[0022] A second aspect of this application provides a control device for a vehicle steering system, comprising:

[0023] The determination unit is used to determine the vehicle status based on the vehicle's operating data;

[0024] Control unit, used for:

[0025] When the vehicle is determined to be in a steering obstacle encounter state, a preset safety protection angle is set as the target angle of the steering actuator, and the steering actuator is controlled to rotate to the target angle at a first angle change speed. The safety protection angle is determined according to the current protection threshold of the actuator motor. The first angle change speed is the actual angle change speed of the pinion gear of the steering actuator, and the first angle change speed is not greater than the preset change speed threshold.

[0026] When the vehicle is determined to be in an obstacle-encountering state, the target angle is controlled to change from the safety protection angle to the commanded steering angle according to the duration. The commanded steering angle is related to the vehicle's target steering angle, and the duration is the length of time the vehicle is in the obstacle-encountering state.

[0027] Optionally, when the determining unit determines the vehicle status based on the vehicle's operating data, it is specifically used for:

[0028] The vehicle status is determined based on the real-time current and speed data of the actuator motor, as well as the vehicle's obstacle warning signal.

[0029] Optionally, the determining unit determines the vehicle status based on the real-time current data and real-time speed data of the actuator motor, as well as the vehicle's obstacle detection signal, including:

[0030] If, within a preset first time period, the current value corresponding to the real-time current data is greater than the first current threshold and the speed value corresponding to the real-time speed data is less than the first speed threshold, the vehicle state is determined to be a steering obstacle encounter state, and the vehicle obstacle encounter signal is set to a high bit.

[0031] When the obstacle encounter signal switches from a high position to a low position, the vehicle status is determined to be an obstacle encounter state when turning out.

[0032] Optionally, the determining unit is further configured to:

[0033] When the vehicle is determined to be in a turning obstacle encounter state, the obstacle encounter direction is determined based on the current direction corresponding to the real-time current data.

[0034] The beneficial effects of this application are as follows:

[0035] When the vehicle is in a steering obstacle encounter state, the steering actuator is controlled to rotate to a safe protection angle at a low angle change rate. This not only protects the actuator motor, ensuring that the current of the actuator motor does not exceed the current protection threshold, but also controls the rate at which the current of the actuator motor decreases by controlling the angle change rate, thus avoiding large current fluctuations and improving the stability of the steer-by-wire system. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0037] Figure 1 This is a functional schematic diagram of a steering obstacle detection motor controller provided in an embodiment of this application;

[0038] Figure 2 A flowchart of a control method for a vehicle steering system provided in an embodiment of this application;

[0039] Figure 3 A schematic diagram of an obstacle detection signal provided in an embodiment of this application;

[0040] Figure 4 A schematic diagram illustrating the variation pattern of the first and second coefficients provided in this application embodiment;

[0041] Figure 5 This is a schematic diagram of the structure of a control device for a vehicle steering system provided in an embodiment of this application. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] Obstacle encounter during steering refers to a situation where, when a vehicle is turning, the steering wheels cannot turn to the corresponding angle as instructed by an obstacle next to them. Obstacle encounter during steering can occur in various situations. For example, a vehicle parked on the side of the road may be unable to turn its steering wheels to the required angle due to an obstruction from a curb when attempting to turn.

[0044] To address the issue of significant current fluctuations that may occur in steer-by-wire systems under obstacle-encroachment conditions, this application provides a control method for a vehicle steering system. This method can be implemented by… Figure 1 The steering obstacle encounter action shown is executed by the motor controller (hereinafter referred to as the controller).

[0045] like Figure 1As shown, the controller can obtain real-time current data, real-time speed data, obstacle detection signal and command steering angle. It processes these input data through obstacle detection execution status judgment, steering angle following mode, obstacle detection slow descent and obstacle exit slow descent control logic, and finally outputs the target angle of the road wheel actuator (RWA) to control the RWA to rotate to the target angle.

[0046] In this embodiment, the target angle of RWA can be the target angle of the pinion gear of RWA. When RWA rotates to the target angle, it can be understood that the pinion gear of RWA rotates to the target angle.

[0047] Please see Figure 2 The following is a flowchart of a control method for a vehicle steering system provided in an embodiment of this application. The method may include the following steps.

[0048] S201 determines the vehicle status based on the vehicle's operating data.

[0049] When the vehicle status is determined to be a steering obstacle encounter, step S202 is executed.

[0050] When the vehicle status is determined to be an obstacle encountering a turning point, step S203 is executed.

[0051] When the vehicle status is determined to be non-obstacle-prone, step S204 is executed.

[0052] Optionally, the method provided in this embodiment can be executed only when it is determined that the vehicle is in a steering state. The way to determine that the vehicle is in a steering state can be by recognizing a steering command or by recognizing that the steering angle of the vehicle body has deflected.

[0053] Vehicle operating data can include real-time current data, real-time speed data, and obstacle warning signals.

[0054] When acquiring operational data, the steering obstacle detection motor controller can also acquire the commanded steering angle, or it can acquire the commanded steering angle when executing step S203 or S204.

[0055] The implementation of S201 can be as follows:

[0056] The vehicle status is determined based on the real-time current and speed data of the actuator motor, as well as the vehicle's obstacle warning signal.

[0057] Real-time current data refers to the real-time current data of the actuator motor of the RWA. Real-time current data can characterize the current value and direction passing through the actuator motor in real time, where the current direction can be represented by the positive or negative sign of the current value.

[0058] The controller can acquire real-time current data from the actuator motor via a current sensor. This real-time current data can also be used to calculate the actual output torque of the actuator motor. In this embodiment, to ensure the accuracy of the vehicle status detected in S201, the accuracy requirement for the real-time current data is an error of less than or equal to 0.01A.

[0059] Real-time speed data refers to the real-time speed data of the actuator motor in the RWA (Real-Time Wiring System). Real-time speed data characterizes the real-time speed value and direction of rotation of the actuator motor; the direction of rotation can be represented by the positive or negative sign of the speed value. The controller can detect the actuator motor's angle signal in real time using the rotor position sensor. The real-time speed data is obtained by differentiating the real-time angle signal over time. The accuracy requirement for the motor's angle signal is an error of less than or equal to 0.1 degrees.

[0060] The obstacle encounter signal can be identified by the obstacle encounter recognition module. In this embodiment, the state of the obstacle encounter signal can be divided into a high bit and a low bit, where the low bit is represented by 0. When the obstacle encounter signal is 0, it means that the vehicle is turning without encountering an obstacle. The high bit can be represented by 1 or 2. 1 indicates a left-facing obstacle encounter, that is, the obstacle encountered is on the left, and 2 indicates a right-facing obstacle encounter, that is, the obstacle encountered is on the right.

[0061] In this embodiment, the controller can determine the target angle of RWA based on the commanded steering angle. The commanded steering angle can be understood as the steering angle specified by the steering command obtained by the vehicle. This steering command can be generated by the vehicle controller based on the target steering angle of the vehicle, or it can be obtained by the driver performing corresponding operations (such as turning the steering wheel) based on the target steering angle.

[0062] After obtaining the above operational data, the controller can determine the vehicle status in the following manner:

[0063] When the current value corresponding to the real-time current data is greater than the first current threshold and the speed value corresponding to the real-time speed data is less than the first speed threshold within the preset first time period, the vehicle status is determined to be a steering obstacle encounter state, and the vehicle obstacle encounter sign signal is set to high bit.

[0064] For example, the first duration can be 20 milliseconds (ms), the first current threshold can be 82A, and the first speed threshold can be 6 degrees per second (degps). In this case, if the controller finds that the current value is greater than 82A, the speed value is less than 6 degps, and this situation lasts for more than 20ms, the controller determines that the vehicle is in a steering obstacle encounter state.

[0065] Optionally, the method provided in this embodiment further includes:

[0066] When the vehicle is determined to be in a turning obstacle encounter state, the obstacle encounter direction is determined based on the current direction corresponding to the real-time current data.

[0067] In the obstacle encounter state, the controller can further determine whether the obstacle is to the left or right based on the current direction in the real-time current data. If it is to the left, the obstacle encounter flag signal can be set to 1; if it is to the right, the obstacle encounter flag signal can be set to 2.

[0068] When the obstacle warning signal switches from a high position to a low position, the vehicle status is determined to be an obstacle encountering state before turning.

[0069] The obstacle detection signal can switch from a high bit to a low bit, which may include decreasing from 1 to 0 or from 2 to 0.

[0070] When the obstacle encounter signal is detected as 0, the vehicle status is determined to be non-obstacle encounter.

[0071] The status of the obstacle warning signal for different vehicle conditions can be found in [reference]. Figure 3 .

[0072] S202, set the preset safety protection angle as the target angle of the steering actuator, and control the steering actuator to rotate to the target angle at a first angle change speed. The safety protection angle is determined according to the current protection threshold of the actuator motor. The first angle change speed is the change speed of the actual angle of the pinion of the steering actuator. The first angle change speed is not greater than the preset change speed threshold.

[0073] The first angle change rate refers to the rate at which the actual angle of the pinion gear in the steering actuator changes during its rotation. Correspondingly, controlling the steering actuator to rotate to the target angle at the first angle change rate essentially means controlling the actual angle of the pinion gear in the steering actuator to change according to the first change rate until the steering actuator rotates from its original angle to the target angle.

[0074] When the vehicle is determined to be in a steering obstacle encounter state, the actuator motor enters a current output safety limit state. Once in this state, the controller can smoothly reduce the actuator motor's current output to the current protection threshold by controlling the target angle the actuator motor is following. The current protection threshold can be set according to actual conditions and is not limited; for example, it can be set to 60A.

[0075] The aforementioned safety protection angles can be the preset safety protection angles of the obstacle detection soft-lock motor controller.

[0076] In step S202, the controller can obtain the safety protection angle from the obstacle detection soft lock motor controller, and then set the safety protection angle θ3 as the target angle θ2 of RWA. That is, at this time, the safety protection angle and the target angle satisfy the following relationship.

[0077] RWA's target angle θ2 = safety protection angle θ3

[0078] Then, based on the target angle, the actuator motor is controlled to follow the rotation angle, so that the actual angle of the RWA pinion gradually coincides with the target angle.

[0079] In the process of angle following by the actuator motor based on the safety protection angle control, the current of the actuator motor can be controlled to gradually decrease by limiting the rate of change of the target angle, thereby achieving the effect of synchronous gradual decrease control of the target angle θ2 and the current of RWA.

[0080] Specifically, the control method could be that the controller limits the first angle change rate of the RWA pinion during the angle following process to a range less than or equal to a given change rate threshold.

[0081] The above control strategy can be called the motor current output slow-down strategy, which is the aforementioned obstacle encounter slow-down strategy.

[0082] S203 controls the target angle to change from a safety protection angle to a command steering angle based on the duration. The command steering angle is related to the vehicle's target steering angle, and the duration is the length of time the vehicle is in the obstacle-encountering state.

[0083] In this embodiment, the controller can determine the vehicle state as out of obstacle state when it detects that the target steering direction of the RWA is opposite to the obstacle direction, and then reduce the obstacle encounter signal from a high bit of 1 or 2 to 0. The target steering direction can be determined based on the current direction of the actuator motor.

[0084] Once the vehicle status is determined to be out of obstacle state, the controller can perform target angle transition control on the RWA in the following manner:

[0085] The first and second coefficients are determined to be linearly related to the duration. The first coefficient decreases from 1 to 0 as the duration increases, and the second coefficient increases from 0 to 1 as the duration increases.

[0086] The target angle is obtained by summing the product of the first coefficient and the safety protection angle, and the product of the second coefficient and the command steering angle.

[0087] When the target angle is determined in the above manner, the target angle, the command steering angle, and the safety protection angle satisfy the following relationship.

[0088] RWA target angle θ2 = command turning angle θ1 × A2 + safety protection angle θ3 × A1

[0089] A1 is the first coefficient, and A2 is the second coefficient. The values ​​of the first and second coefficients are both between 0 and 1, and their sum is always 1, i.e., A1 + A2 = 1.

[0090] In this embodiment, A1 and A2 can change over time according to the RWA pinion target angle transition control rule.

[0091] The RWA pinion target angle transition control rule refers to the coefficient A2 gradually increasing from 0 and the coefficient A1 gradually decreasing from 1, until the coefficients A2 = 1 and A1 = 0. When A1 = 1 and A2 = 0, the target angle of RWA is the safety protection angle; when A1 = 0 and A2 = 1, the target angle of RWA is equal to the angle given by the steering command, that is, the command steering angle.

[0092] Furthermore, when A1=0 and A2=1, the controller can terminate the steering obstacle encounter state and exit the control logic of the target angle transition control.

[0093] The first coefficient can gradually decrease to 0 within a second period of time after the controller detects the steering obstacle encounter state, and the second coefficient can gradually increase to 1 within the second period of time. The second period of time can be set according to the actual situation and is not limited.

[0094] For example, the second duration can be set to 100 milliseconds (ms), in which case the changes of the first and second coefficients over time are as follows: Figure 4 As shown, in this case, the first coefficient can change according to the rule A1 = 1 - t / 100ms, and the second coefficient can change according to the rule A2 = t / 100ms, until the second duration ends and the controller exits the target angle transition control.

[0095] After determining the target angle in the above manner, the controller can control the RWA pinion to rotate following the target angle by executing the motor, so that the target angle becomes the commanded steering angle, and at the same time, the actual angle of the RWA pinion coincides with the commanded steering angle.

[0096] The above control method can be called RWA pinion target angle transition control, which is the aforementioned obstacle exit descent strategy.

[0097] S204 sets the command steering angle to the target angle of the steering actuator and controls the steering actuator to rotate to the target angle.

[0098] When the obstacle encounter flag A signal is detected as 0, the obstacle encounter execution status module determines that the current vehicle is in an obstacle-free state. In this case, the controller can directly set the commanded steering angle given by the steering command to the target angle of RWA, and then perform angle following control on the execution motor based on the target angle, so that the actual angle of the pinion of RWA coincides with the commanded steering angle.

[0099] In this case, the target angle and the command steering angle of RWA satisfy the following relationship.

[0100] RWA target angle θ2 = command turning angle θ1

[0101] The beneficial effects of this embodiment are as follows:

[0102] Firstly, the control method of this embodiment provides a control method for a steer-by-wire system in the event of a steering obstacle, enabling a vehicle with steer-by-wire to perform appropriate operations when encountering a steering obstacle.

[0103] Secondly, the control method of this embodiment judges the vehicle state when turning based on the vehicle's operating data, thereby accurately identifying whether the vehicle encounters an obstacle when turning, as well as the direction of the obstacle, and providing a basis for subsequent control.

[0104] Thirdly, when the vehicle is in a steering obstacle encounter state, the angle of the steering actuator is related to the current of the actuator motor. The control scheme of this embodiment can control the steering actuator to rotate to a safe protection angle, thereby controlling the current of the actuator motor to not exceed the current protection threshold, avoiding damage to the actuator motor. Furthermore, this scheme controls the rate of decrease of the current of the actuator motor by limiting the speed of the first angle change during rotation, thereby avoiding large current jitter in the actuator motor and improving the stability of the steer-by-wire system under steering obstacle encounter conditions.

[0105] Fourthly, when the vehicle is in a state of encountering obstacles while turning, this solution can control the target angle to gradually transition from the safety protection angle to the steering angle specified by the steering command, thereby improving the smoothness of the transition process and enhancing the driving experience.

[0106] Through the above-described control method for the steer-by-wire system under obstacle-encounter conditions, this embodiment can perform smooth angle following control of the target angle of the RWA, thereby achieving smooth control of the actuator motor, which is beneficial to improving the stability and smoothness of the vehicle system, and thus helps to improve the driving experience.

[0107] According to the vehicle steering system control method provided in the embodiments of this application, the embodiments of this application also provide a vehicle steering system control device. Please refer to [link to relevant documentation]. Figure 5 This is a schematic diagram of the structure of the device, which may include the following units.

[0108] The determining unit 501 is used to determine the vehicle status based on the vehicle's operating data;

[0109] Control unit 502 is used for:

[0110] When the vehicle status is determined to be a steering obstacle encounter state, the preset safety protection angle is set as the target angle of the steering actuator, and the steering actuator is controlled to rotate to the target angle at a first angle change speed. The safety protection angle is determined according to the current protection threshold of the actuator motor. The first angle change speed is the actual angle change speed of the steering actuator pinion, and the first angle change speed is not greater than the preset change speed threshold.

[0111] When the vehicle is determined to be in an obstacle-crossing state, the target angle is changed from a safety protection angle to a commanded steering angle based on the duration. The commanded steering angle is related to the vehicle's target steering angle, and the duration is the length of time the vehicle is in the obstacle-crossing state.

[0112] Optionally, when determining the vehicle status based on the vehicle's operating data, the determining unit 501 is specifically used for:

[0113] The vehicle status is determined based on the real-time current and speed data of the actuator motor, as well as the vehicle's obstacle warning signal.

[0114] Optionally, when determining the vehicle status based on the real-time current data and real-time speed data of the actuator motor, and the vehicle's obstacle warning signal, the determining unit 501 is specifically used for:

[0115] When the current value corresponding to the real-time current data is greater than the first current threshold and the speed value corresponding to the real-time speed data is less than the first speed threshold within the preset first time period, the vehicle status is determined to be a steering obstacle encounter state, and the vehicle obstacle encounter sign signal is set to high bit.

[0116] When the obstacle warning signal switches from a high position to a low position, the vehicle status is determined to be an obstacle encountering state before turning.

[0117] Optionally, the determining unit 501 is also used for:

[0118] When the vehicle is determined to be in a turning obstacle encounter state, the obstacle encounter direction is determined based on the current direction corresponding to the real-time current data.

[0119] Optionally, when the control unit 502 controls the target angle to change from a safety protection angle to a command steering angle based on the duration, it is specifically used for:

[0120] The first and second coefficients are determined to be linearly related to the duration. The first coefficient decreases from 1 to 0 as the duration increases, and the second coefficient increases from 0 to 1 as the duration increases.

[0121] The target angle is obtained by summing the product of the first coefficient and the safety protection angle, and the product of the second coefficient and the command steering angle.

[0122] Optionally, the control unit 502 is also used for:

[0123] When the vehicle is determined to be in an obstacle-free state, the commanded steering angle is set to the target angle of the steering actuator, and the steering actuator is controlled to rotate to the target angle.

[0124] The specific working principle and beneficial effects of the vehicle steering system device provided in this embodiment can be found in the relevant steps and beneficial effects of the vehicle steering system control method provided in any embodiment of this application, and will not be repeated here.

[0125] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0126] It should be noted that the concepts of "first" and "second" mentioned in this invention are only used to distinguish different devices, modules or units, and are not used to limit the order of functions performed by these devices, modules or units or their interdependencies.

[0127] Those skilled in the art will be able to implement or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for a vehicle steering system, characterized in that, include: Determine the vehicle status based on the vehicle's operating data; When the vehicle is determined to be in a steering obstacle encounter state, a preset safety protection angle is set as the target angle of the steering actuator, and the steering actuator is controlled to rotate to the target angle at a first angle change speed. The safety protection angle is determined according to the current protection threshold of the actuator motor. The first angle change speed is the actual angle change speed of the pinion gear of the steering actuator, and the first angle change speed is not greater than the preset change speed threshold. When the vehicle is determined to be in an obstacle-encountering state, the target angle is controlled to change from the safety protection angle to the commanded steering angle according to the duration. The commanded steering angle is related to the vehicle's target steering angle, and the duration is the length of time the vehicle is in the obstacle-encountering state. The step of controlling the target angle to change from the safety protection angle to the command steering angle based on the duration includes: A first coefficient and a second coefficient are determined that are linearly related to the duration, wherein the first coefficient decreases from 1 to 0 as the duration increases, and the second coefficient increases from 0 to 1 as the duration increases; The target angle is obtained by summing the product of the first coefficient and the safety protection angle, and the product of the second coefficient and the command steering angle.

2. The method according to claim 1, characterized in that, Determining the vehicle status based on the vehicle's operating data includes: The vehicle status is determined based on the real-time current and speed data of the actuator motor, as well as the vehicle's obstacle warning signal.

3. The method according to claim 2, characterized in that, The step of determining the vehicle status based on the real-time current data and real-time speed data of the actuator motor, as well as the vehicle's obstacle detection signal, includes: If, within a preset first time period, the current value corresponding to the real-time current data is greater than the first current threshold and the speed value corresponding to the real-time speed data is less than the first speed threshold, the vehicle state is determined to be a steering obstacle encounter state, and the vehicle obstacle encounter signal is set to a high bit. When the obstacle encounter signal switches from a high position to a low position, the vehicle status is determined to be an obstacle encounter state when turning out.

4. The method according to claim 3, characterized in that, Also includes: When the vehicle is determined to be in a turning obstacle encounter state, the obstacle encounter direction is determined based on the current direction corresponding to the real-time current data.

5. The method according to claim 1, characterized in that, Also includes: When the vehicle is determined to be in an obstacle-free state, the command steering angle is set to the target angle of the steering actuator, and the steering actuator is controlled to rotate to the target angle.

6. A control device for a vehicle steering system, characterized in that, include: The determination unit is used to determine the vehicle status based on the vehicle's operating data; Control unit, used for: When the vehicle is determined to be in a steering obstacle encounter state, a preset safety protection angle is set as the target angle of the steering actuator, and the steering actuator is controlled to rotate to the target angle at a first angle change speed. The safety protection angle is determined according to the current protection threshold of the actuator motor. The first angle change speed is the actual angle change speed of the pinion gear of the steering actuator, and the first angle change speed is not greater than the preset change speed threshold. When the vehicle is determined to be in an obstacle-encountering state, the target angle is controlled to change from the safety protection angle to the commanded steering angle according to the duration. The commanded steering angle is related to the vehicle's target steering angle, and the duration is the length of time the vehicle is in the obstacle-encountering state. When the control unit controls the target angle to change from a safety protection angle to a command steering angle according to the duration, it is specifically used for: A first coefficient and a second coefficient are determined that are linearly related to the duration, wherein the first coefficient decreases from 1 to 0 as the duration increases, and the second coefficient increases from 0 to 1 as the duration increases; The target angle is obtained by summing the product of the first coefficient and the safety protection angle, and the product of the second coefficient and the command steering angle.

7. The apparatus according to claim 6, characterized in that, When the determining unit determines the vehicle status based on the vehicle's operating data, it is specifically used for: The vehicle status is determined based on the real-time current and speed data of the actuator motor, as well as the vehicle's obstacle warning signal.

8. The apparatus according to claim 7, characterized in that, The determining unit determines the vehicle status based on the real-time current data and real-time speed data of the actuator motor, as well as the vehicle's obstacle detection signal, including: If, within a preset first time period, the current value corresponding to the real-time current data is greater than the first current threshold and the speed value corresponding to the real-time speed data is less than the first speed threshold, the vehicle state is determined to be a steering obstacle encounter state, and the vehicle obstacle encounter signal is set to a high bit. When the obstacle encounter signal switches from a high position to a low position, the vehicle status is determined to be an obstacle encounter state when turning out.

9. The apparatus according to claim 8, characterized in that, The determining unit is further configured to: When the vehicle is determined to be in a turning obstacle encounter state, the obstacle encounter direction is determined based on the current direction corresponding to the real-time current data.

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