Steer-by-wire power-on synchronization control method and device, controller, vehicle and medium

Abstract

The embodiment of the invention provides a steering-by-wire power-on synchronization control method and device, a controller, a vehicle and a medium. The method comprises the following steps: after a vehicle is powered on, determining an angle error according to a steering wheel angle of the vehicle and a steering wheel synchronization target angle; according to the angle error, a target rotating speed corresponding to the angle error is determined from a preset angle rotating speed mapping table, and steering wheel rotating speeds corresponding to different angle errors are stored in the angle rotating speed mapping table; according to the target rotating speed, controlling a steering wheel of the vehicle to rotate to synchronize the steering wheel with the wheel angle. The method is used for achieving the effect of improving the safety performance of the vehicle in the process of electrifying and synchronizing the angles of the steering wheel and the wheels.

Description

Technical Field

[0001] The present application relates to a vehicle steer-by-wire technology, and more particularly to a steer-by-wire power-on synchronous control method, device, controller, vehicle and medium. Background Art

[0002] To meet the development needs of intelligent driving, the automotive steering system uses full wire control technology to replace the traditional steering system. The mechanical connection between the steering systems is eliminated, reducing the spatial layout restrictions between the steering system mechanics, providing a good foundation for the design of intelligent driving cockpits; however, after the vehicle is powered off, if the steering wheel is turned, the wheels cannot receive the steering request of the steering wheel, so the wheels will not turn with the steering wheel, causing the steering wheel and wheels to be out of sync, posing a safety hazard.

[0003] In the prior art power-on synchronization mechanism, when synchronizing the steering wheel angle with the wheel angle, the steering wheel is directly controlled according to the target angle. However, the prior art method has a potential safety hazard caused by excessive steering wheel rotation speed during the steering wheel angle synchronization process. Summary of the invention

[0004] The embodiments of the present application provide a method, device, controller, vehicle and medium for controlling power-on synchronization of steer-by-wire, so as to improve the safety performance of the vehicle during the process of synchronizing the steering wheel and wheel angles when powered on.

[0005] In a first aspect, an embodiment of the present application provides a method for controlling power-on synchronization of a steer-by-wire system, comprising:

[0006] After the vehicle is powered on, determining an angle error according to a steering wheel angle of the vehicle and a steering wheel synchronization target angle;

[0007] According to the angle error, determining a target speed corresponding to the angle error from a preset angle-speed mapping table, wherein the angle-speed mapping table stores steering wheel speeds corresponding to different angle errors;

[0008] According to the target rotation speed, the steering wheel of the vehicle is controlled to rotate so as to synchronize the steering wheel with the wheel angle.

[0009] In a possible implementation manner, controlling the steering wheel rotation of the vehicle to synchronize the steering wheel with the wheel angle according to the target rotation speed includes:

[0010] According to the target rotation speed, controlling the steering wheel rotation of the vehicle, and obtaining a new angle error between a real-time steering wheel angle and the steering wheel synchronization target angle;

[0011] Obtaining a new target speed corresponding to the new angle error from the angle-speed mapping table, and continuing to control the rotation of the steering wheel according to the new target speed;

[0012] Repeat the above steps until the steering wheel reaches the steering wheel synchronization target angle.

[0013] In a possible implementation manner, controlling the rotation of the steering wheel of the vehicle according to the target speed includes:

[0014] Acquiring a speed error signal according to the target speed and the current speed of the steering wheel;

[0015] The speed error signal is input into a PID controller, and the steering wheel is driven to rotate according to the output response of the PID controller.

[0016] In a possible implementation, the method further includes:

[0017] During the steering wheel rotation process, if it is detected that the angle error between the real-time steering wheel angle and the steering wheel synchronization target angle reaches a preset angle error dead zone, the PID controller is controlled to reduce the output response or stop the output response.

[0018] In a possible implementation manner, inputting the speed error signal into a PID controller, and driving the steering wheel to rotate according to an output response of the PID controller, comprises:

[0019] The speed error signal is input into the PID controller so that the PID controller controls the output response to drive the steering wheel to rotate according to the speed error signal and preset control parameters; wherein the control parameters include preset speed error dead zone and integral anti-saturation upper and lower limits.

[0020] In a possible implementation manner, determining, according to the angle error, a target speed corresponding to the angle error from a preset angle-speed mapping table includes:

[0021] If the angle error is greater than or equal to a preset angle error threshold, a target speed corresponding to the angle error is determined from a preset angle-speed mapping table according to the angle error.

[0022] In a possible implementation manner, determining the angle error according to the steering wheel angle of the vehicle and the steering wheel synchronization target angle includes:

[0023] Determining whether the vehicle is in a synchronizable state according to a vehicle state of the vehicle and a controller state;

[0024] When the vehicle is in a synchronizable state, the angle error is determined according to a steering wheel angle of the vehicle and a steering wheel synchronization target angle.

[0025] In a possible implementation, the method further includes:

[0026] If the angle error is less than the angle error threshold and the duration is greater than a preset duration threshold, it is determined that the steering wheel and the wheel angle of the vehicle are synchronized.

[0027] In a second aspect, an embodiment of the present application provides a steer-by-wire power-on synchronization control device, comprising:

[0028] A first determination module is used to determine an angle error according to a steering wheel angle of the vehicle and a steering wheel synchronization target angle after the vehicle is powered on;

[0029] a second determination module, configured to determine, according to the angle error, a target speed corresponding to the angle error from a preset angle-speed mapping table, wherein the angle-speed mapping table stores steering wheel speeds corresponding to different angle errors;

[0030] The control module is used to control the steering wheel rotation of the vehicle to synchronize the steering wheel with the wheel angle according to the target rotation speed.

[0031] In a possible implementation manner, the control module is specifically used to:

[0032] According to the target rotation speed, controlling the steering wheel rotation of the vehicle, and obtaining a new angle error between a real-time steering wheel angle and the steering wheel synchronization target angle;

[0033] Obtaining a new target speed corresponding to the new angle error from the angle-speed mapping table, and continuing to control the rotation of the steering wheel according to the new target speed;

[0034] Repeat the above steps until the steering wheel reaches the steering wheel synchronization target angle.

[0035] In a possible implementation manner, the control module is specifically used to:

[0036] During the steering wheel rotation process, if it is detected that the angle error between the real-time steering wheel angle and the steering wheel synchronization target angle reaches a preset angle error dead zone, the PID controller is controlled to reduce the output response or stop the output response.

[0037] In a possible implementation manner, the control module is specifically used to:

[0038] The speed error signal is input into the PID controller so that the PID controller controls the output response to drive the steering wheel to rotate according to the speed error signal and preset control parameters; wherein the control parameters include preset speed error dead zone and integral anti-saturation upper and lower limits.

[0039] In a possible implementation manner, the second determining module is specifically configured to:

[0040] If the angle error is greater than or equal to a preset angle error threshold, a target speed corresponding to the angle error is determined from a preset angle-speed mapping table according to the angle error.

[0041] In a specific implementation, the first determining module is specifically configured to:

[0042] Determining whether the vehicle is in a synchronizable state according to a vehicle state of the vehicle and a controller state;

[0043] When the vehicle is in a synchronizable state, the angle error is determined according to a steering wheel angle of the vehicle and a steering wheel synchronization target angle.

[0044] In a specific implementation, the first determining module is specifically configured to:

[0045] If the angle error is less than the angle error threshold and the duration is greater than a preset duration threshold, it is determined that the steering wheel and the wheel angle of the vehicle are synchronized.

[0046] In a third aspect, an embodiment of the present application provides a controller, including: a processor, a memory, and a communication interface;

[0047] The memory stores computer-executable instructions;

[0048] The processor executes the computer-executable instructions stored in the memory to implement the power-on synchronization control method for wire-controlled steering as described in any one of the first aspects.

[0049] In a fourth aspect, the present application provides a vehicle, comprising: a vehicle body, and a controller as described in the third aspect.

[0050] In a fifth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the first aspect above and / or various possible implementations of the first aspect.

[0051] In a sixth aspect, an embodiment of the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the above first aspect and / or various possible implementation methods of the first aspect.

[0052] The embodiments of the present application provide a method, device, controller, vehicle and medium for power-on synchronization control of steer-by-wire. After the vehicle is powered on, the method first determines the angle error based on the steering wheel angle of the vehicle and the steering wheel synchronization target angle, then determines the target speed corresponding to the angle error from a preset angle-speed mapping table, and finally controls the steering wheel rotation of the vehicle based on the target speed to synchronize the steering wheel and wheel angles. During the process of synchronizing the steering wheel and wheel angles when the vehicle is powered on, the steering wheel rotation is controlled by the target speed to achieve the effect of improving the safety performance of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0054] Figure 1 A schematic flow chart of an embodiment of a method for controlling power-on synchronization of steer-by-wire provided in the present application;

[0055] Figure 2 A flowchart of a specific synchronization state judgment method of the wire-controlled steering power-on synchronization control method provided by the present application;

[0056] Figure 3 A flow chart of a specific speed closed-loop PID control method of the wire-controlled steer-on power-on synchronization control method provided in the present application;

[0057] Figure 4 A flowchart of a specific embodiment of the power-on synchronous control method for steer-by-wire provided in the present application;

[0058] Figure 5 A schematic diagram of the structure of a power-on synchronous control device for steer-by-wire provided in an embodiment of the present application;

[0059] Figure 6 A schematic diagram of the structure of a controller provided in an embodiment of the present application.

[0060] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0061] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0062] First, the concepts involved in this application are explained:

[0063] Full-wire control technology: Full-wire control technology is a technology that uses electronic signals to replace traditional mechanical connections to achieve device or system control. It uses sensors to monitor the status of the device or system in real time, converts the monitored data into electrical signals, and transmits them to the Electronic Control Unit (ECU) through wires or wires. After receiving the signal, the ECU performs necessary processing and calculations, then generates control instructions, and then transmits the instructions to the actuator through wires or wires to achieve control of the device or system.

[0064] PID controller: Proportional-Integral-Derivative Controller (PID) controller is a classic control algorithm widely used in automotive electronic control systems. It calculates and adjusts the control quantity of the system so that the parameters of each system of the vehicle can accurately and stably reach the desired state.

[0065] In order to clearly understand the technical solution of the present application, the solution of the prior art is introduced in detail below.

[0066] To meet the development needs of intelligent driving, the automotive steering system uses full-wire control technology to replace the traditional steering system. This full-wire control technology eliminates the mechanical connection between the steering systems, reduces the spatial layout restrictions between the steering system machinery, provides a good foundation for the design of intelligent driving cockpits, and also increases the possibility of coordination between the steering system and other chassis systems.

[0067] However, since the mechanical connection between the steering wheel and the steering gear is eliminated in the steer-by-wire technology, the control algorithm of the steering feeling fed back to the driver has undergone a huge change. Especially after the vehicle is parked and powered off, when the driver turns the steering wheel, the wheels cannot execute the steering request of the steering wheel, so the wheels will not turn accordingly, resulting in the phenomenon that the steering wheel angle and the wheel steering angle are out of sync, which will undoubtedly pose a challenge to the safety of the steering system, is not conducive to the promotion of steer-by-wire technology, and affects the driving experience of the steer-by-wire chassis.

[0068] The existing related technologies will directly perform strong angle control on the steering wheel angle when the vehicle is powered on for the first time, so that the steering wheel angle is synchronized with the wheel angle. However, the power-on synchronization control method of the existing technology ignores the speed problem when the steering wheel is synchronized, which will undoubtedly lead to the high-speed steering wheel burying hidden dangers to the driver's safety in the actual functional experience. In addition, the power-on synchronization control method of the existing technology has the problems of overshoot and small-angle jitter of the steering wheel angle synchronization, which will lead to a very poor driving experience for the driver.

[0069] In view of the technical problems in the above technical background, the inventors consider obtaining the angle error between the steering wheel angle of the vehicle and the steering wheel synchronization target angle (the steering wheel synchronization target angle comes from the wheel angle at power-on) after the vehicle is powered on, and then finding the target speed corresponding to the angle error from the preset angle speed mapping table, and using the target angle as the control factor in the steering wheel rotation process to control the steering wheel to rotate to the target angle at a suitable speed that meets the safety index. This method enables the wire-controlled steering wheel to have the property of actively synchronizing the wheel angle when it is first powered on, so as to improve the safety of the wire-controlled steering system in multiple usage scenarios, and solves the technical problem that the steering wheel speed is too fast during the power-on synchronization process, which poses a safety hazard to the driver.

[0070] The power-on synchronization control method for wire-controlled steering provided in the present application is mainly used in control systems, for example, in the steering ECU of a vehicle's wire-controlled steering system, and the present application does not impose any restrictions on this.

[0071] In a specific application scenario, when the vehicle is powered off, the steering wheel angle of the vehicle is not synchronized with the wheel angle. Therefore, when the vehicle is powered on for the first time, the steering ECU of the vehicle first determines the angle error based on the steering wheel angle collected by the angle sensor with the target synchronization angle of the steering wheel, where the target synchronization angle of the steering wheel is the wheel angle at power-on; then, the target speed corresponding to the error angle is determined in the pre-set angle speed mapping table; and then the PID controller is controlled according to the target speed to output a synchronization signal to the drive motor or actuator. Finally, the drive motor or actuator drives the steering wheel to rotate to the target synchronization angle in response to the synchronization signal.

[0072] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0073] Figure 1 The flowchart of the embodiment of the wire-controlled steering power-on synchronous control method provided by the present application is as follows Figure 1 As shown, the method includes:

[0074] S101. After the vehicle is powered on, determine an angle error according to a steering wheel angle of the vehicle and a steering wheel synchronization target angle.

[0075] This solution is applied to the scenario where the vehicle is powered on for the first time.

[0076] In this step, the steering wheel angle is determined based on the steering wheel angle signal captured by the vehicle's steering angle sensor; the steering wheel synchronization target angle is determined based on the wheel angle signal captured by the vehicle's steering angle sensor when the wheel is initially powered on, wherein the wheel angle signal at the initial power-on is also called the steering wheel synchronization target angle signal. The angle error can be determined by subtracting the steering wheel angle from the steering wheel synchronization target angle. The obtained angle error is used to determine the deviation of the steering wheel angle from the wheel angle.

[0077] In a possible implementation, the collected vehicle steering wheel angle signal and steering wheel synchronization target angle signal may first be input into a low pass filter (LPF) for filtering to obtain a steering wheel angle signal from which high-frequency noise is filtered out and a steering wheel synchronization target angle signal from which high-frequency noise is filtered out; then, the steering wheel angle and the steering wheel synchronization target angle are determined based on the steering wheel angle signal from which high-frequency noise is filtered out and the steering wheel synchronization target angle signal from which high-frequency noise is filtered out; and then, based on the determined steering wheel angle and the steering wheel synchronization target angle, the angle error is determined.

[0078] In this embodiment, it should be understood that this method filters out signal noise in the signal by inputting the steering wheel angle signal and the steering wheel synchronization target angle signal into the LPF for low-pass filtering, thereby effectively avoiding the influence of sensor noise on the angle error. It is worth noting that the cutoff frequency of the low-pass filter needs to be set according to the inherent properties of the input signal and the expected signal accuracy.

[0079] In a possible implementation manner, the angle error may be calculated by taking the absolute value of the difference between the steering wheel angle and the steering wheel synchronization target angle.

[0080] In this embodiment, it should be understood that the steering wheel angle may deviate from the synchronization target angle to the left or to the right. The steering wheel deviates in different directions, and the angle error obtained by direct difference will have a sign difference problem. This method effectively solves the problem of angle error sign difference by taking the absolute value of the value after difference, eliminating its influence on the subsequent data processing process.

[0081] In one possible implementation, after the vehicle is powered on, it is first determined whether the vehicle is in a synchronizable state based on the vehicle state and the controller state; when the vehicle is in a synchronizable state, the angle error is determined based on the vehicle's steering wheel angle and the steering wheel synchronization target angle.

[0082] The vehicle status includes: vehicle powered on and vehicle powered off; the controller status includes: initialization completed and incomplete initialization. Specifically, when the vehicle status is vehicle powered on and the controller status is initialization completed, the vehicle is considered to be in a synchronizable state; otherwise, the vehicle is considered to be in an unsynchronizable state.

[0083] In this embodiment, it should be understood that when the vehicle is in a non-synchronizable state, executing the synchronization action will cause problems with the steering function of the vehicle, thereby causing driving safety problems. Therefore, before determining the angle error, judging the synchronizable state of the vehicle can improve the overall safety of the vehicle.

[0084] S102. Determine, according to the angle error, a target speed corresponding to the angle error from a preset angle-speed mapping table, wherein the angle-speed mapping table stores steering wheel speeds corresponding to different angle errors.

[0085] In this step, in order to realize the control of the steering wheel speed during the power-on synchronization of the steering wheel, an angle-speed mapping table needs to be pre-configured. The angle-speed mapping table stores the steering wheel speeds corresponding to different angle errors, wherein the steering wheel speed corresponding to each angle error is obtained based on experimental tests. In a specific application, according to the obtained angle error, the speed corresponding to the angle error in the pre-set angle-speed mapping table is queried, and the speed is used as the target speed of the steering wheel.

[0086] In one possible implementation, the determined angle error can be first compared with a preset angle error threshold, and then a determination is made based on the comparison result whether a steering wheel synchronization action is required, that is, whether a target speed corresponding to the angle error is determined from a preset angle-speed mapping table based on the angle error.

[0087] In a specific application, if the angle error is greater than or equal to a preset angle error threshold, the target speed corresponding to the angle error is determined from a preset angle speed mapping table according to the angle error. The preset angle error threshold is based on the specific implementation situation. For example, the angle error threshold may be 0.1 rad. This application does not limit the size of the angle error threshold.

[0088] In a more specific implementation, after the vehicle is powered on, the angle error at the current moment is obtained in real time, and the angle error at the current moment is compared with the preset angle error threshold in real time to obtain the synchronization state of the vehicle steering wheel in real time. When the synchronization state of the vehicle steering wheel is an asynchronous state, the steering wheel synchronization action in step S102 is performed again, that is, according to the angle error, a target speed corresponding to the angle error is determined from a preset angle speed mapping table.

[0089] In this embodiment, it should be understood that the threshold value of the angle error is determined in advance, which not only takes into account the need to ensure the uniformity of the angle between the steering wheel and the tire, but also avoids the problem of frequent jumps in synchronization status caused by small deviations. By setting a reasonable angle error threshold, this method can effectively avoid misjudgments caused by factors such as environmental noise or sensor drift while ensuring steering accuracy, thereby improving the stability and reliability of the wire control steering system.

[0090] S103: According to the target rotation speed, control the steering wheel rotation of the vehicle to synchronize the steering wheel with the wheel angle.

[0091] In this step, in order to synchronize the steering wheel angle with the wheel angle and control the steering wheel speed during the steering wheel synchronization process, it is necessary to control the steering wheel rotation according to the target speed corresponding to the angle error obtained by the query, until the steering wheel angle rotates to the synchronization target angle to achieve synchronization with the wheel angle.

[0092] In a possible implementation, the steering ECU controls the PID controller to output a synchronizing torque to the drive motor or the actuator in real time, and the drive motor or the actuator drives the steering wheel to rotate according to the synchronizing torque received in real time so as to synchronize the steering wheel with the wheel angle. The synchronizing torque output by the PID controller in real time is determined according to the target speed. It should be understood that in this process, the drive motor or the actuator regulates the actual speed of the steering wheel according to the received synchronizing torque, so as to control the steering wheel speed during the synchronizing action of the steering wheel.

[0093] In the specific implementation of this solution, it should be understood that according to the target speed, controlling the steering wheel rotation of the vehicle to synchronize the steering wheel with the wheel angle may include two implementations:

[0094] Embodiment 1: The target speed corresponding to the angle error at the initial moment is used as the target speed in the whole process of the steering wheel rotating to the synchronization target angle, and the steering wheel rotation of the vehicle is controlled according to the target speed to synchronize the steering wheel with the wheel angle.

[0095] Implementation method 2: acquiring the angular error between the steering wheel angle and the steering wheel synchronization target angle in real time, and querying and acquiring the target speed corresponding to the angular error at the current moment from the angle-speed mapping table in real time. According to the target speed acquired in real time, the steering wheel rotation of the vehicle is controlled to synchronize the steering wheel with the wheel angle. Specifically, according to the target speed, the steering wheel rotation of the vehicle is controlled, and a new angular error between the real-time steering wheel angle and the steering wheel synchronization target angle is acquired; a new target speed corresponding to the new angular error is acquired from the angle-speed mapping table, and the steering wheel rotation is continued to be controlled according to the new target speed; and the aforementioned steps are repeated until the steering wheel reaches the steering wheel synchronization target angle.

[0096] In a possible implementation, controlling the steering wheel rotation of the vehicle according to the target speed in the above two implementations includes: obtaining a speed error signal according to the target speed and the current speed of the steering wheel; inputting the speed error signal into a PID controller, and driving the steering wheel rotation through the output response of the PID controller.

[0097] In this embodiment, it should be understood that the target speed is subtracted from the current speed of the steering wheel obtained in real time to obtain a real-time changing speed error signal, and then the real-time changing speed error signal is input into the PID controller as a synchronous feedback control; the PID controller outputs a real-time changing synchronization torque that drives the steering wheel to rotate according to the input real-time changing speed error signal, and the real-time changing synchronization torque can regulate the speed of the steering wheel during the steering wheel rotation process. Therefore, the real-time monitoring and adjustment of the steering wheel speed is achieved, ensuring that the steering wheel can be rotated smoothly and accurately to the synchronous target angle.

[0098] In a possible implementation, during the steering wheel rotation process, if it is detected that the angle error between the real-time steering wheel angle and the steering wheel synchronization target angle reaches a preset angle error dead zone, the PID controller is controlled to reduce the output response or stop the output response.

[0099] In this embodiment, during the steering wheel rotation process, it is detected in real time whether the angle error between the actual steering wheel angle and the steering wheel synchronization target angle falls into the preset angle error dead zone, and when the real-time angle error falls into the preset angle error dead zone, the steering ECU controls the PID controller to temporarily stop the action or reduce its output response. That is, when the actual steering wheel angle is close to the steering wheel synchronization target angle, the steering ECU controls the PID controller to temporarily stop the action or reduce its output response.

[0100] Exemplarily, when it is detected that the angle error between the real-time steering wheel angle and the steering wheel synchronization target angle reaches a preset angle error dead zone, the steering ECU sets the integral term in the PID controller to zero.

[0101] It should be understood that this embodiment can effectively suppress the slight shaking of the steering wheel caused by excessive accumulation of integral terms in the PID control strategy by setting a reasonable dead zone range, significantly reduce the small vibration of the steering wheel near the target angle, and improve driving comfort and system stability.

[0102] On the basis of the above implementation, further, the speed error signal is input into a PID controller, and the steering wheel is driven to rotate according to the output response of the PID controller, including:

[0103] The speed error signal is input into the PID controller so that the PID controller controls the output response to drive the steering wheel to rotate according to the speed error signal and preset control parameters; wherein the control parameters include preset speed error dead zone and integral anti-saturation upper and lower limits.

[0104] In this embodiment, it should be understood that the control parameters include not only the restriction conditions (such as the speed error dead zone, the upper and lower limits of the integral anti-saturation), but also the key parameters of the PID controller. The key parameters of the PID controller are, for example, proportional gain, integral gain, differential gain, etc. Among them, the setting of restriction conditions improves the response speed and robustness of the wire control steering system, reduces unnecessary energy consumption and mechanical wear caused by over-adjustment or under-adjustment, and effectively suppresses the slight shaking of the steering wheel caused by excessive accumulation of integral terms, thereby improving the driving experience of the driver.

[0105] In a possible implementation, after the vehicle is powered on, if the angle error is less than an angle error threshold and the duration is greater than a preset duration threshold, it is determined that the steering wheel and the vehicle's wheel angles are synchronized.

[0106] In this embodiment, it should be understood that in order to effectively avoid the phenomenon that the real-time angle error detected passes the synchronization target angle due to accidental factors such as instantaneous interference or measurement noise during the process of the steering wheel rotating to the target synchronization angle, and the synchronization mechanism is turned off. This method ensures the accuracy and stability of the synchronization state judgment, improves the robustness of the overall control strategy, and reduces unnecessary control actions.

[0107] The wire-controlled steer-by-wire synchronization control method provided in the present embodiment determines the angle error based on the steering wheel angle of the vehicle and the steering wheel synchronization target angle after the vehicle is powered on, then determines the target speed corresponding to the angle error from a preset angle-speed mapping table, and finally controls the steering wheel rotation of the vehicle based on the target speed to synchronize the steering wheel and wheel angles. In the process of synchronizing the steering wheel and wheel angles when the vehicle is powered on, the present embodiment uses the angle error as a feedback control for synchronization, effectively regulating the steering wheel speed, so as to achieve the effect of improving the safety performance of the vehicle.

[0108] Based on the above embodiments, Figure 2 The present application provides a flowchart of a specific synchronization state judgment method of the wire control steering power-on synchronization control method. After the vehicle is powered on for the first time, the following method can be used: Figure 2 The method shown detects the synchronization state of the steering wheel in real time and adjusts the synchronization strategy in time according to the synchronization state of the steering wheel.

[0109] S201. Input the steering wheel angle signal and the steering wheel synchronization target angle signal into a low-pass filter for low-pass filtering.

[0110] S202, determine the synchronizable state of the vehicle. When the vehicle is powered on and the controller is initialized, it is considered to be in a synchronizable state and meets the synchronizable condition; otherwise, it is considered to be in a non-synchronizable state and does not meet the synchronizable condition.

[0111] S203. When the vehicle meets the synchronization conditions, determine the steering wheel angle and the steering wheel synchronization target angle according to the filtered vehicle steering wheel angle signal and the filtered steering wheel synchronization target angle signal, and subtract the steering wheel angle from the steering wheel synchronization target angle and take the absolute value to obtain the angle error.

[0112] S204. Compare the angle error with a preset angle error threshold. When the angle error is less than the preset angle error threshold, it is considered that the angle condition is met; when the angle error is greater than or equal to the preset angle error threshold, it is considered that the angle condition is not met.

[0113] S205 and S206, when the vehicle meets the angle condition, determine the duration of meeting the angle condition. When the duration of meeting the angle condition is greater than or equal to the preset time threshold, it is considered that the time condition is met; when the duration of meeting the angle condition is less than the preset time threshold, it is considered that the time condition is not met;

[0114] S207: For the case where the synchronizable condition is not met in step S202, the angle condition is not met in step S204, or the time condition is not met in step S206, it is considered that the synchronization state of the vehicle steering wheel is not synchronized;

[0115] S208. For the case where the synchronizable condition in step S202, the angle condition in step S204, and the time condition in step S206 are satisfied at the same time, it is considered that the synchronization state of the vehicle steering wheel is synchronized.

[0116] It should be understood that after the vehicle is powered on, the steering ECU can use the method for judging the synchronization state of the steering wheel provided in this embodiment in real time to judge the synchronization state of the vehicle steering wheel. And according to the change of the synchronization state of the vehicle steering wheel, adjust the synchronization control strategy of the steering wheel in real time. This mechanism not only simplifies the design and implementation of the subsequent control logic, but also facilitates fault diagnosis and maintenance. At the same time, it ensures that the system can respond to changes in steering operations in a timely manner, improving driving experience and safety. The methods in the above steps correspond to the methods used in various possible implementations in the previous embodiment, and their implementation principles and technical effects are similar, so this embodiment will not be repeated here.

[0117] Figure 3 The flowchart of a specific speed closed-loop PID control method of the wire-controlled steering power-on synchronous control method provided in this application is as follows. Figure 3 As shown in the figure, when the vehicle steering wheel is in an unsynchronized state, the steering ECU controls the vehicle's steering wheel rotation in the following manner to synchronize the steering wheel with the wheel angle:

[0118] S301, when the steering wheel state is not synchronized, determining an angle error according to the steering wheel angle of the vehicle and a steering wheel synchronization target angle;

[0119] S302, determining whether the angle error reaches a preset angle error dead zone;

[0120] S303, determining a target speed corresponding to the angle error from a preset angle-speed mapping table according to the acquired angle error;

[0121] S304: Input the target speed corresponding to the angle error and the current speed of the steering wheel into the PID controller. The PID controller adjusts its output signal according to the speed error signal determined by the target speed and the current speed of the steering wheel, the key parameters of the PID controller, the speed error dead zone, and the upper and lower limits of the integral anti-saturation; if it is determined in step S302 that the angle error reaches the preset angle error dead zone, the PID controller is controlled to reduce the output response or stop the output response.

[0122] It should be understood that the output signal of the PID controller is used to drive the steering wheel to rotate to the synchronization target angle, and its size is used to control the speed of the steering wheel. This method can not only accurately control the synchronization speed of the steering wheel at different synchronization angles, but also effectively reduce the overshoot and small angle jitter at the synchronization target angle.

[0123] Figure 4 This is a flow chart of a specific embodiment of the wire-controlled steering power-on synchronization control method provided in this application. Figure 4 As shown, the wire-controlled steering power-on synchronous control method includes:

[0124] S401, after the vehicle is powered on, use Figure 2 The steering wheel synchronization state judgment method shown judges the synchronization state of the steering wheel;

[0125] S402, when the synchronization state of the steering wheel is synchronization, the synchronization torque is equal to zero;

[0126] S403, when the synchronous state of the steering wheel is not synchronous, the synchronous torque is equal to the following Figure 3 The output signal of the PID controller obtained by the speed closed-loop PID control method shown;

[0127] S404: Output the synchronous torque to the drive motor or the actuator.

[0128] It is worth noting that in the specific implementation of this solution, it is not only necessary to determine whether to execute step S403 based on the synchronization status bit, but also to consider whether other status bits of the vehicle meet the synchronization conditions. For example, in the case where the synchronization condition is not met in step S202, although the synchronization status of the steering wheel is not synchronized, since the status bit of its controller is not initialized, step S403 will not be executed at this time. Step S403 will not be executed until the vehicle is in a synchronized state.

[0129] For example, setting Figure 2 The preset time threshold in is 3, and the initial time i=0. If the angle error is greater than the preset angle error threshold after the vehicle is powered on, the synchronization state bit of the steering wheel is 0. Since the synchronization state bit of the steering wheel is 0, the output signal of the PID controller is used as the synchronization torque in real time and output to the drive motor or actuator; the drive motor or actuator drives the steering wheel to rotate in real time according to the synchronization torque obtained in real time. Before the steering wheel rotates to the synchronization target angle, at a certain moment, it is detected that the angle error obtained in real time is less than the preset angle error threshold (caused by accidental factors). At this time, i=1, and the time condition is not met. Therefore, the synchronization state bit of the steering wheel is still 0, and the output signal of the PID controller needs to continue to be used as the synchronization torque and output to the drive motor or actuator; the drive motor or actuator continues to drive the steering wheel to rotate according to the synchronization torque obtained in real time. Until after multiple synchronization bit judgments and i≥3, the synchronization bit of the steering wheel is set to 1, and the synchronization torque is set to zero and output to the drive motor or actuator. At this point, the power-on synchronization of the steering wheel angle is completed.

[0130] The specific power-on synchronization control method for steer-by-wire provided in this embodiment uses angle error as feedback control for synchronization. After the vehicle is powered on, the synchronization state of the steering wheel is judged in real time, and the steering wheel angle is adjusted according to the synchronization state of the steering wheel. When the steering wheel is out of sync, the target speed corresponding to the angle error is determined by obtaining the angle error and from a preset angle-speed mapping table, and the steering wheel rotation of the vehicle is controlled according to the target speed to synchronize the steering wheel with the wheel angle. Using this method, not only can the synchronization speed of the steering wheel at different synchronization angles be accurately controlled to improve the safety performance of the vehicle, but also the overshoot and small-angle jitter at the synchronization target angle can be effectively weakened, thereby improving the driving experience of the driver.

[0131] Figure 5 A schematic diagram of the structure of the power-on synchronous control device for wire-controlled steering provided in an embodiment of the present application is shown in FIG. Figure 5 As shown, the power-on synchronous control device 50 provided by the present embodiment includes:

[0132] A first determination module 501 is used to determine an angle error according to a steering wheel angle and a steering wheel synchronization target angle of the vehicle after the vehicle is powered on;

[0133] A second determination module 502 is used to determine a target speed corresponding to the angle error from a preset angle-speed mapping table according to the angle error, wherein the angle-speed mapping table stores steering wheel speeds corresponding to different angle errors;

[0134] The control module 503 is used to control the rotation of the steering wheel of the vehicle to synchronize the steering wheel with the wheel angle according to the target rotation speed.

[0135] In a possible implementation manner, the control module 503 is specifically configured to:

[0136] According to the target rotation speed, controlling the steering wheel rotation of the vehicle, and obtaining a new angle error between a real-time steering wheel angle and the steering wheel synchronization target angle;

[0137] Obtaining a new target speed corresponding to the new angle error from the angle-speed mapping table, and continuing to control the rotation of the steering wheel according to the new target speed;

[0138] Repeat the above steps until the steering wheel reaches the steering wheel synchronization target angle.

[0139] In a possible implementation manner, the control module 503 is specifically configured to:

[0140] During the steering wheel rotation process, if it is detected that the angle error between the real-time steering wheel angle and the steering wheel synchronization target angle reaches a preset angle error dead zone, the PID controller is controlled to reduce the output response or stop the output response.

[0141] In a possible implementation manner, the control module 503 is specifically configured to:

[0142] The speed error signal is input into the PID controller so that the PID controller controls the output response to drive the steering wheel to rotate according to the speed error signal and preset control parameters; wherein the control parameters include preset speed error dead zone and integral anti-saturation upper and lower limits.

[0143] In a possible implementation manner, the second determining module 502 is specifically configured to:

[0144] If the angle error is greater than or equal to a preset angle error threshold, a target speed corresponding to the angle error is determined from a preset angle-speed mapping table according to the angle error.

[0145] In a specific implementation, the first determining module 501 is specifically configured to:

[0146] Determining whether the vehicle is in a synchronizable state according to a vehicle state of the vehicle and a controller state;

[0147] When the vehicle is in a synchronizable state, the angle error is determined according to a steering wheel angle of the vehicle and a steering wheel synchronization target angle.

[0148] In a specific implementation, the first determining module 501 is specifically configured to:

[0149] If the angle error is less than the angle error threshold and the duration is greater than a preset duration threshold, it is determined that the steering wheel and the wheel angle of the vehicle are synchronized.

[0150] The steer-by-wire power-on synchronization control device 50 provided in this embodiment can execute the method provided in the above method embodiment, and its implementation principle and technical effect are similar, so this embodiment will not be described in detail here.

[0151] Figure 6 This is a schematic diagram of the structure of the controller provided in the embodiment of the present application. Figure 6 , the controller 60 may include a processor 601 , a memory 602 and a communication interface 603 . Exemplarily, the processor 601 , the memory 602 and the communication interface 603 are interconnected via a bus 604 .

[0152] The memory 602 stores computer-executable instructions;

[0153] The processor 601 executes the computer-executable instructions stored in the memory 602 , so that the processor 601 performs the power-on synchronization control method for steer-by-wire provided in the above method embodiment.

[0154] Accordingly, an embodiment of the present application provides a vehicle, wherein the vehicle includes a vehicle body and a controller 60 .

[0155] Accordingly, an embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the power-on synchronous control method for wire-controlled steering described in the above method embodiment.

[0156] Accordingly, an embodiment of the present application may also provide a computer program product, including a computer program. When the computer program is executed by a processor, the power-on synchronization control method for wire-controlled steering described in the above method embodiment can be implemented.

[0157] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0158] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A method for controlling power-on synchronization of a steer-by-wire system, characterized in that: include: After the vehicle is powered on, determining an angle error according to a steering wheel angle of the vehicle and a steering wheel synchronization target angle; According to the angle error, determining a target speed corresponding to the angle error from a preset angle-speed mapping table, wherein the angle-speed mapping table stores steering wheel speeds corresponding to different angle errors; According to the target rotation speed, the steering wheel of the vehicle is controlled to rotate so as to synchronize the steering wheel with the wheel angle.

2. The method according to claim 1, characterized in that The step of controlling the steering wheel rotation of the vehicle to synchronize the steering wheel with the wheel angle according to the target rotation speed comprises: According to the target rotation speed, controlling the steering wheel rotation of the vehicle, and obtaining a new angle error between a real-time steering wheel angle and the steering wheel synchronization target angle; Obtaining a new target speed corresponding to the new angle error from the angle-speed mapping table, and continuing to control the rotation of the steering wheel according to the new target speed; Repeat the above steps until the steering wheel reaches the steering wheel synchronization target angle.

3. The method according to claim 1 or 2, characterized in that: The step of controlling the rotation of the steering wheel of the vehicle according to the target rotation speed comprises: Acquiring a speed error signal according to the target speed and the current speed of the steering wheel; The speed error signal is input into a PID controller, and the steering wheel is driven to rotate according to the output response of the PID controller.

4. The method according to claim 3, characterized in that The method further comprises: During the steering wheel rotation process, if it is detected that the angle error between the real-time steering wheel angle and the steering wheel synchronization target angle reaches a preset angle error dead zone, the PID controller is controlled to reduce the output response or stop the output response.

5. The method according to claim 3, characterized in that: The step of inputting the speed error signal into a PID controller and driving the steering wheel to rotate according to an output response of the PID controller comprises: The speed error signal is input into the PID controller so that the PID controller controls the output response to drive the steering wheel to rotate according to the speed error signal and preset control parameters; wherein the control parameters include preset speed error dead zone and integral anti-saturation upper and lower limits.

6. The method according to any one of claims 1, 2, 4 or 5, characterized in that: Determining a target speed corresponding to the angle error from a preset angle-speed mapping table according to the angle error includes: If the angle error is greater than or equal to a preset angle error threshold, a target speed corresponding to the angle error is determined from a preset angle-speed mapping table according to the angle error.

7. The method according to any one of claims 1, 2, 4 or 5, characterized in that: The determining the angle error according to the steering wheel angle of the vehicle and the steering wheel synchronization target angle includes: Determining whether the vehicle is in a synchronizable state according to a vehicle state of the vehicle and a controller state; When the vehicle is in a synchronizable state, the angle error is determined according to a steering wheel angle of the vehicle and a steering wheel synchronization target angle.

8. The method according to claim 6, characterized in that The method further comprises: If the angle error is less than the angle error threshold and the duration is greater than a preset duration threshold, it is determined that the steering wheel and the wheel angle of the vehicle are synchronized.

9. A power-on synchronous control device for steer-by-wire, characterized in that: include: A first determination module is used to determine an angle error according to a steering wheel angle of the vehicle and a steering wheel synchronization target angle after the vehicle is powered on; a second determination module, configured to determine, according to the angle error, a target speed corresponding to the angle error from a preset angle-speed mapping table, wherein the angle-speed mapping table stores steering wheel speeds corresponding to different angle errors; The control module is used to control the steering wheel rotation of the vehicle to synchronize the steering wheel with the wheel angle according to the target rotation speed.

10. A controller, characterized in that: include: Processor, memory and communication interface; The memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory to implement the power-on synchronous control method for steer-by-wire according to any one of claims 1 to 8.

11. A vehicle, characterized in that: include: A vehicle body, and a controller as claimed in claim 10.

12. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 1 to 8 when executed by a processor.

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