Steer-by-wire system function control method and device, vehicle and medium

Abstract

The embodiment of the application provides a kind of drive-by-wire steering system function control method, device, vehicle and medium.The method is applied to road feel simulator, the rotation angle data of steering wheel is collected in real time, and the rotation of the steering wheel of vehicle is controlled in combination with the maximum rotation angle of steering wheel.The maximum rotation angle of steering wheel is determined according to the maximum rotation angle of vehicle wheel and transmission ratio parameter.Transmission ratio parameter refers to the proportional relationship between steering wheel rotation and wheel rotation.Through the above method, the accurate control of steering wheel rotation is realized, which makes it rotate within a reasonable range, simplifies the rotation range of steering wheel in drive-by-wire steering system, improves the controllability and safety of vehicle, and is suitable for the development and application of modern intelligent driving system.

Description

Technical Field

[0001] This application relates to the field of automotive electronics technology, and in particular to a method, device, vehicle, and medium for controlling the function of a steer-by-wire system. Background Technology

[0002] To meet the demands of intelligent driving development, automotive steering systems employ full steer-by-wire technology, eliminating the mechanical connection between the steering wheel and wheels and overcoming the spatial limitations of steering system mechanisms. However, because the steering wheel is decoupled from the tires, the driver cannot feel the resistance generated by the steering system or the friction between the tires and the ground through the steering wheel. This creates a safety hazard due to a mismatch between the steering wheel's rotation and the capability of the steering actuator motor.

[0003] The common approach to limiting the steering wheel's rotation range to ensure it matches the capability of the steering actuator motor is the torque curve calibration scheme. The torque curve describes the amount of torque the motor should apply under different steering wheel angles, vehicle speeds, and road conditions. Sensors acquire parameters such as the current steering wheel angle, rotation speed, and vehicle speed to determine the current driving state. The system then searches for the corresponding torque value in a predefined torque curve. However, due to the large number and complexity of parameters, the torque curve calibration scheme is not conducive to engineering implementation.

[0004] In summary, providing a technical solution that can effectively address the complexities of implementing a steering wheel rotation range limitation scheme in a steer-by-wire system is an urgent technical problem to be solved. Summary of the Invention

[0005] This application provides a method, device, vehicle, and medium for controlling the function of a steer-by-wire system, which simplifies the complexity of the steering wheel rotation range limitation scheme in the steer-by-wire system.

[0006] In a first aspect, embodiments of this application provide a method for controlling the function of a steer-by-wire system, applied to a vehicle's road feel simulator, the method comprising:

[0007] Real-time acquisition of steering wheel angle data of the vehicle;

[0008] The steering wheel rotation is controlled based on the steering wheel angle and the maximum steering wheel rotation angle; wherein the maximum steering wheel rotation angle is determined based on the maximum wheel rotation angle and transmission ratio parameters of the vehicle.

[0009] In one possible implementation, controlling the rotation of the steering wheel based on the steering wheel's angle and its maximum rotation angle includes:

[0010] If the angle difference between the turning angle and the maximum turning angle of the steering wheel is less than a first preset value, resistance is applied in the direction of steering wheel rotation, and the magnitude of the resistance is proportional to the size of the turning angle.

[0011] In one possible implementation, the method further includes:

[0012] If the turning angle reaches the maximum turning angle of the steering wheel, then the rotation of the steering wheel is locked.

[0013] In one possible implementation, the locking of the steering wheel rotation includes:

[0014] By applying a preset maximum resistance to the direction of steering wheel rotation, the rotation of the steering wheel is locked.

[0015] In one possible implementation, the method further includes:

[0016] If the steering wheel center position is detected, the resistance applied to the steering wheel will be reduced to zero.

[0017] In one possible implementation, the method further includes:

[0018] The maximum steering wheel rotation angle is obtained by calculating the product of the maximum wheel rotation angle and the transmission ratio parameter.

[0019] In one possible implementation, the method further includes:

[0020] When the difference between the current tire rotation angle and the maximum tire rotation angle of the vehicle is detected to be less than a second preset value, the tire response steering speed of the vehicle is reduced.

[0021] The tire response steering speed is inversely proportional to the current tire steering angle of the vehicle.

[0022] Secondly, embodiments of this application provide a steer-by-wire system function control device, applied to a vehicle road feel simulator, comprising:

[0023] The first processing module is used to collect the steering wheel angle data of the vehicle in real time;

[0024] The second processing module is used to control the rotation of the steering wheel based on the steering wheel angle and the maximum steering wheel rotation angle; wherein the maximum steering wheel rotation angle is determined based on the maximum wheel rotation angle and transmission ratio parameters of the vehicle.

[0025] Thirdly, embodiments of this application provide a road feel simulator, including:

[0026] Memory, processor;

[0027] The memory stores computer-executed instructions;

[0028] The processor executes computer execution instructions stored in the memory, causing the processor to perform the first aspect and / or various possible implementations of the first aspect as described above.

[0029] Fourthly, embodiments of this application provide a vehicle, including: the main structure of the vehicle and a road feel simulator as described in the third aspect.

[0030] Fifthly, embodiments of this application provide a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the first aspect and / or various possible implementations of the first aspect.

[0031] Fifthly, embodiments of this application provide a computer program product, including a computer program that, when executed by a processor, implements the first aspect and / or various possible implementations of the first aspect.

[0032] The steer-by-wire system control method, device, vehicle, and medium provided in this application control the steering wheel rotation by real-time acquisition of steering wheel angle data and combining it with the maximum steering wheel rotation angle. The maximum steering wheel rotation angle is determined based on the maximum wheel rotation angle and the transmission ratio parameter. The transmission ratio parameter refers to the proportional relationship between steering wheel rotation and wheel rotation. Through this method, precise parameter calculation and real-time data acquisition achieve precise control of steering wheel rotation, ensuring it rotates within a reasonable range. This simplifies the structure limiting the steering wheel rotation range in steer-by-wire systems, thereby improving vehicle handling and safety. Attached Figure Description

[0033] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0034] Figure 1 A schematic diagram of a scenario for a steer-by-wire system function control method provided in this application;

[0035] Figure 2 A flowchart illustrating a functional control method for a steer-by-wire system provided in this application. Figure 1 ;

[0036] Figure 3 A schematic diagram of a specific implementation of the steer-by-wire system function control method provided in this application. Figure 1 ;

[0037] Figure 4 A schematic diagram of a specific implementation of the steer-by-wire system function control method provided in this application. Figure 2 ;

[0038] Figure 5 A schematic diagram of a specific implementation of the steer-by-wire system function control method provided in this application. Figure 3 ;

[0039] Figure 6 A schematic diagram of a specific implementation of the steer-by-wire system function control method provided in this application. Figure 4 ;

[0040] Figure 7 A schematic diagram of a specific implementation of the steer-by-wire system function control method provided in this application. Figure 5 ;

[0041] Figure 8 A schematic diagram of the overall flow of a steer-by-wire system function control method provided in this application;

[0042] Figure 9 A schematic diagram of the structure of a functional control device for a steer-by-wire system provided in this application;

[0043] Figure 10 This is a schematic diagram of the structure of a road feel simulator provided in this application.

[0044] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0045] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0046] First, let me explain the terms used in this application:

[0047] Permanent Magnet Synchronous Motor (PMSM): A PMSM is a high-efficiency motor widely used in industry, automotive, and household appliances. Its key feature is that permanent magnets are embedded in the rotor, eliminating the need for external excitation to generate a magnetic field. When the stator windings are energized, a rotating magnetic field is generated, and the rotor rotates synchronously with the stator magnetic field under the influence of the permanent magnets, hence the name synchronous motor. No current flows through the rotor of a PMSM, reducing energy loss and improving overall efficiency. Furthermore, PMSMs exhibit good dynamic response and speed regulation performance, maintaining high efficiency across a wide speed range. Their simple structure, small size, and light weight make them ideal for electric vehicles, wind turbines, and high-performance industrial drive systems.

[0048] Rotor: The rotating part of an electric motor or generator, typically composed of conductive and magnetic materials. In an electric motor, the rotor achieves rotational motion through interaction with the magnetic field generated by the stator, thereby converting electrical energy into mechanical energy.

[0049] The stator is the stationary part of a motor or generator, typically composed of an iron core and winding coils. Its primary function is to generate a magnetic field or induced current. In a motor, the stator generates a rotating magnetic field by passing an electric current through it, which interacts with the rotor to drive its rotation. In a generator, the stator is the component that induces current; as the rotor rotates, an electromotive force is generated in the stator windings. The rotor and stator together constitute the core working components of a motor or generator, and their interaction is crucial for energy conversion.

[0050] H-bridge circuit: A circuit topology used to control the direction and speed of a DC motor, its shape resembling the letter "H". An H-bridge circuit consists of four switching elements, typically transistors or metal-oxide-semiconductor field-effect transistors (MOSFETs), connected in a bridge configuration across the motor. By controlling the on and off states of the switches, the polarity of the voltage across the motor can be changed, thus controlling the motor's forward, reverse, and stop movements. Specifically, when two diagonal switches are on, current flows through the motor in one direction, causing it to rotate; when the other two diagonal switches are on, the current flows in the opposite direction, causing the motor to rotate in the opposite direction. The H-bridge circuit can not only control the motor's rotation direction but also precisely control the average voltage and current of the motor through the duty cycle of a pulse-width modulation (PWM) signal, thereby achieving speed control.

[0051] The application background of this application is explained below:

[0052] With the rapid development of automotive electronics technology, in order to meet the needs of intelligent driving development, the automotive steering system adopts full-drive technology to replace the traditional steering system, eliminating the mechanical connection between the steering wheel and the wheels, breaking through the spatial layout limitations of the steering system's mechanical components, providing a good foundation for the design of intelligent driving cockpits, and increasing the possibility of cooperation between the steering system and other chassis systems.

[0053] In traditional steering systems, the steering wheel is mechanically connected to the wheels, and its angle of motion depends on the length of the steering motor rack. This inherent physical limitation ensures a limited range of motion. In steer-by-wire systems, the steering wheel is decoupled from the wheels, allowing for unlimited rotation due to the lack of mechanical connection. However, the steering motor rack still has a length limitation. Therefore, in some situations, the steering wheel's rotation angle may exceed the motor's achievable angle, resulting in a difference between the perceived steering wheel rotation and the actual wheel rotation. At high speeds or in extreme conditions, if the steering wheel's rotation exceeds the motor's physical limit, the rack inside the motor may move to its limit position and impact the motor's end, causing wear and damage, and compromising driving safety.

[0054] The commonly used method for limiting steering wheel rotation range is the torque curve calibration scheme. This involves simulating the steering wheel's reverse torque to discourage the driver from turning it too far, ensuring the steering wheel's rotation matches the capability of the steering actuator motor. The curve describes the magnitude of the torque the motor should apply under different steering wheel angles, vehicle speeds, and road conditions. Sensors acquire parameters such as the current steering wheel angle, rotation speed, and vehicle speed to determine the current driving state. The system then searches for the corresponding torque value in a predefined torque curve. However, due to the large number and complexity of parameters, improper torque application or an unsatisfactory steering actuator motor response can lead to steering wheel vibration or rebound. The torque curve calibration scheme for limiting steering wheel rotation range is complex to implement and not conducive to engineering practice.

[0055] In summary, providing a technical solution that can effectively address the complexities of implementing a steering wheel rotation range limitation scheme in a steer-by-wire system is an urgent technical problem to be solved.

[0056] Figure 1 This application provides a schematic diagram of a scenario for a steer-by-wire system function control method, such as... Figure 1As shown, the specific application scenarios of this application include road feel simulators, steering actuator motors, and steering wheels. The road feel simulator communicates with the control unit of the steering actuator motor via the vehicle's communication bus, such as the Controller Area Network (CAN) bus. The control unit can send the rack position information of the steering actuator motor, i.e., the wheel's rotation angle and angular velocity, to the road feel simulator in real time. The road feel simulator can obtain the steering wheel's rotation angle and angular velocity, as well as the magnitude of its simulated resistance. Based on the wheel's rotation angle and angular velocity, the steering wheel's rotation angle and angular velocity, and the magnitude of its simulated resistance, the road feel simulator employs a series of measures to control the vehicle, including a speed reduction response strategy before the steering actuator motor's end position, hand force prompts, and entering or exiting the motor phase lock-up mode, to ensure that the steering wheel's rotation matches the steering actuator motor's capabilities.

[0057] The physical devices mentioned above are illustrative and not unique. This application does not specifically limit the specific form or type of the physical devices involved. It should be noted that the steer-by-wire system function control method provided in this application can be used in the field of automotive electronics technology, as well as in fields other than automotive electronics technology. This application does not specifically limit its application field.

[0058] Based on the above scenario, it is evident that in existing technologies, the method of simulating the application of reverse torque to the steering wheel through torque curve calibration to prevent the driver from turning the wheel and ensuring that the steering wheel rotation matches the capability of the steering actuator motor suffers from numerous and complex parameters, making the limitation of the steering wheel rotation range difficult to implement and hindering engineering feasibility. In the process of researching steer-by-wire systems and limiting the steering wheel rotation range to ensure that the steering wheel rotation matches the capability of the steering actuator motor, the inventors discovered that simulating the steering wheel end effect using a road feel simulator and employing a motor phase lock-up method to simulate end effect limitation can solve the aforementioned problems. This provides a technical solution that effectively addresses the complexity of implementing steering wheel rotation range limitation schemes in steer-by-wire systems. Specifically, the road feel simulator, based on the wheel's turning angle and angular velocity, the steering wheel's turning angle and angular velocity, and the magnitude of its simulated resistance, employs a deceleration response strategy before the steering actuator motor's end position, hand force prompts, and a series of measures including entering or exiting the motor phase lock-up mode to control the vehicle accordingly, achieving the technical effect of matching the steering wheel rotation with the capability of the steering actuator motor. Based on this, this application provides a steer-by-wire system function control method, device, vehicle, and medium.

[0059] The technical solution of this application and how it solves the above-mentioned technical problems will be described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will be described below with reference to the accompanying drawings.

[0060] Figure 2 A flowchart illustrating a functional control method for a steer-by-wire system provided in this application. Figure 1 ,like Figure 2 As shown, the method includes:

[0061] S201. Real-time acquisition of steering wheel angle data of the vehicle.

[0062] The steer-by-wire system in an automobile consists of three main parts: the steering wheel assembly, the steering actuator assembly, and the main controller (Electronic Control Unit, ECU), as well as auxiliary systems such as automatic fault prevention systems and power supplies. The steering wheel assembly includes the steering wheel, a steering wheel angle sensor, a torque sensor, and a steering wheel return torque motor. The steering wheel assembly converts the driver's steering intentions, i.e., the steering wheel angle data, into electrical signals and transmits them to the main controller. This steering wheel angle data includes the steering wheel's rotation angle and angular velocity, reflecting not only the driver's behavioral characteristics and reaction speed but also providing crucial support for the vehicle's safety systems. Through this data, the steer-by-wire system can better understand and predict the driver's intentions, thereby optimizing the vehicle's dynamic response and ensuring safety and stability under various driving conditions.

[0063] Specifically, the steering wheel angle sensor monitors the steering wheel's rotational position and angular velocity in real time and converts them into electrical signals. These signals are transmitted to the road feel simulator via the vehicle network. In different driving scenarios, the steering wheel angle data can be used to analyze driving behavior, such as maneuvering characteristics during turning, lane changing, or emergency avoidance. For example, when encountering an obstacle or a sudden situation, the driver may quickly turn the steering wheel to avoid it. The system can determine the driver's emergency avoidance intention by analyzing the steering wheel's rotation angle and angular velocity in real time, and coordinate with other safety systems, such as automatic emergency braking, to respond in order to minimize the risk of collision.

[0064] S202. Control the rotation of the steering wheel according to the steering wheel angle and the maximum steering wheel rotation angle; wherein, the maximum steering wheel rotation angle is determined according to the maximum wheel rotation angle and transmission ratio parameters of the vehicle.

[0065] Steering wheel rotation is the primary means by which a driver controls the vehicle's direction. In a steer-by-wire system, because the steering wheel is decoupled from the wheels, there is no mechanical connection between them, and without inherent physical limitations, the steering wheel can rotate indefinitely. In this step, by presetting the maximum steering wheel rotation angle, the maximum rotation angle that the vehicle's wheels can achieve is limited, ensuring that under any circumstances, the driver's operation will not exceed the vehicle's physical steering capability, avoiding loss of control or mechanical damage due to oversteering. The gear ratio parameter SteerRation plays a crucial role in ensuring that the maximum steering wheel rotation angle matches the maximum wheel rotation angle. This parameter defines the proportional relationship between steering wheel rotation and wheel rotation, ensuring that every degree of steering wheel rotation is accurately reflected in wheel rotation.

[0066] In one specific implementation, the vehicle steering system achieves wheel movement through the movement of the rack of the steering actuator motor. The TireMap, a core vehicle parameter, describes the mapping relationship between wheel angles and the position of the steering actuator motor's rack, ensuring the vehicle's response accuracy under different steering requirements. Another core parameter, SteerRation, describes the mapping relationship between wheel angles and steering wheel angles; that is, when the steering wheel rotates a certain angle, the corresponding wheel rotation angle can be calculated using SteerRation.

[0067] Specifically, by querying the wheel-rack relationship table TireMap, the maximum wheel rotation angle of the vehicle is obtained when the rack of the steering actuator motor is at the end position LE. ,Right now Next, the maximum steering wheel rotation angle is determined based on the vehicle's maximum wheel rotation angle and SteerRation. Optionally, the maximum steering wheel rotation angle is obtained by calculating the product of the vehicle's maximum wheel rotation angle and the transmission ratio parameter. ,Right now .

[0068] In this step, after calculating the maximum steering wheel rotation angle based on the vehicle's maximum wheel rotation angle and transmission ratio parameters, the road feel simulator controls the steering wheel rotation based on this maximum steering wheel rotation angle and the current steering wheel angle. This prevents the steering wheel from rotating beyond the maximum steering wheel rotation angle, which not only improves the vehicle's handling precision and safety but also ensures the steering wheel's accurate response under different steering requirements, thus enhancing the stability and reliability of the driving experience.

[0069] Figure 3 A schematic diagram of a specific implementation of the steer-by-wire system function control method provided in this application. Figure 1 , Figure 4A schematic diagram of a specific implementation of the steer-by-wire system function control method provided in this application. Figure 2 Based on the above embodiments, controlling the rotation of the steering wheel according to the steering wheel angle and the maximum steering wheel rotation angle can be specifically implemented as follows:

[0070] In the first case, if the angle difference between the turning angle and the maximum turning angle of the steering wheel is less than the first preset value, resistance is applied in the direction of steering wheel rotation, and the magnitude of the resistance is proportional to the size of the turning angle.

[0071] The first preset value determines when the road feel simulator begins to apply resistance to the steering wheel. This preset value is set based on several factors. Firstly, it must ensure that the driver does not suddenly lose control of the vehicle when the steering wheel approaches its maximum turning angle. Secondly, to provide a smooth and natural driving experience, the first preset value must provide adequate feedback without affecting normal driving operations. A first preset value that is too small may result in premature resistance, affecting driving comfort; a first preset value that is too large may fail to provide sufficient feedback in a timely manner. Furthermore, the setting of the first preset value must also consider vehicle characteristics. Different vehicles have different steering system designs and dynamic characteristics, therefore the first preset value needs to be adjusted according to the specific vehicle's characteristics. For example, a smaller first preset value is suitable for sports vehicles to provide more responsive steering feedback, while a larger first preset value is suitable for family sedans to maintain comfort.

[0072] Therefore, the setting of the first preset value needs to take into account factors such as safe driving, driving experience and vehicle characteristics, so as to provide appropriate resistance feedback when approaching the maximum steering wheel rotation angle, gradually reminding the driver to pay attention to the steering limit, ensuring driving safety, and not affecting normal driving operation.

[0073] Optionally, the range of the first preset value can be set to: Specifically, the values ​​can be 30, 50, 60, 70, 90, etc., meaning when the current steering wheel angle reaches... , , , or At that time, the road feel simulator begins to apply resistance in the direction of steering wheel rotation.

[0074] In a specific implementation, such as Figure 3 As shown, the road feel simulator collects the current steering wheel angle in real time. Maximum steering wheel rotation angle The angle difference between them is less than 60 degrees (that is, the first preset value is 60 degrees). At that time, determine the current angular velocity of the steering wheel. Rotation angle of the steering wheel Is the product greater than zero? This indicates that the driver is continuously turning the steering wheel in one direction. The road feel simulator then applies resistance in the direction of steering wheel turning, gradually increasing the hand force to provide a prompt. This simulates greater steering resistance or alerts the driver that the steering wheel is approaching its steering limit. It should be noted that the first preset value of 60 degrees here is merely illustrative and not a specific limitation; in actual implementation, the first preset value needs to be adjusted appropriately according to the actual situation. Figure 4 As shown, the magnitude of the resistance applied by the road feel simulator in the direction of steering wheel rotation is directly proportional to the current rotation angle of the steering wheel. That is, the larger the current rotation angle of the steering wheel, the greater the resistance applied by the road feel simulator in the direction of steering wheel rotation, until the steering wheel rotation angle reaches its maximum rotation angle. The road feel simulator applies resistance in the direction of steering wheel rotation to reach the preset maximum resistance. .

[0075] In the above method, by controlling the steering wheel rotation based on the steering wheel angle and the maximum steering wheel rotation angle, resistance is applied in the direction of steering wheel rotation. The driver can gradually feel the increase in steering resistance, prompting them to pay attention to the steering limits. This provides timely resistance feedback to the driver's steering operation, avoiding oversteering and loss of vehicle control, thereby improving driving safety and experience. Simultaneously, the setting of the first preset value comprehensively considers safe driving, driving experience, and vehicle characteristics, ensuring sufficient feedback without affecting normal driving operations, ultimately achieving a balance between safety and comfort.

[0076] In one specific implementation, in order to control the amount of rebound of the steering wheel after the hand is released, if the steering wheel is detected to be at the center of the steering wheel, the resistance applied to the steering wheel is reduced to zero, thereby reducing the resistance when the steering wheel returns to center and avoiding excessive rebound.

[0077] When the angle difference between the steering wheel's turning angle and its maximum rotation angle is less than a first preset value, the road feel simulator applies resistance in the direction of steering wheel rotation to provide appropriate feedback. At this point, even a slight loosening of the driver's hand will cause the steering wheel to rebound to some extent. Excessive rebound can lead to vehicle instability, especially at high speeds or in emergencies, increasing the driver's workload and causing the vehicle to deviate from its intended trajectory. Therefore, to control the amount of steering wheel rebound after the driver releases their hand, the resistance applied to the steering wheel by the road feel simulator is reduced to zero. This not only effectively ensures a smooth return of the steering wheel to center, providing a more natural driving experience, but also reduces mechanical wear on the steering system, extending its service life.

[0078] In the second scenario, if the steering angle reaches the maximum steering wheel rotation angle, the steering wheel rotation is locked by applying a preset maximum resistance to the steering wheel rotation direction.

[0079] Since the maximum steering wheel rotation angle is the angle at which the steering actuator's rack is at its end position LE, and the wheel's movement is achieved through the movement of the steering actuator's rack, it means that when the steering wheel reaches its maximum rotation angle, the wheel has already rotated to its physical limit. Therefore, a preset maximum resistance must be applied to the steering wheel's rotation direction to lock the steering wheel's rotation and further restrict the wheel's rotation.

[0080] Specifically, the road feel simulator collects the current steering wheel angle in real time. When the steering wheel angle reaches its maximum, that is... At this time, the steering wheel rotation is locked. The road feel simulator then enters motor phase lock-up mode.

[0081] In normal operation, the permanent magnet synchronous motor in the road simulator continuously rotates its rotor under the influence of a rotating magnetic field by constantly changing the phase of the current in the stator windings. In the motor phase-locked mode, a specific current is supplied to the stator windings. This generates a fixed magnetic field, under which the rotor tends to align with or remain in a position consistent with the magnetic field, thereby applying a preset maximum resistance to the direction of steering wheel rotation. The road feel simulator locks the steering wheel's rotation. When the steering wheel reaches its maximum rotation angle, the phase lock effectively locks the steering wheel, preventing the wheels from exceeding their physical limits and ensuring the system's stability and reliability when providing maximum resistance. This not only protects the mechanical components of the steering system from damage but also improves vehicle safety, preventing loss of control due to oversteering.

[0082] Figure 5 A schematic diagram of a specific implementation of the steer-by-wire system function control method provided in this application. Figure 3 Specifically, the road feel simulator uses an H-bridge circuit to control a permanent magnet synchronous motor to achieve phase locking, such as... Figure 5 As shown, the H-bridge circuit is set to fixed switching mode, and a specific current is applied to the three-phase circuit. This keeps the motor in any one of phases A, B, or C. The preset lock-in phase is phase A, so the upper transistor D1 for phase A is off, the lower transistor D5 for phase B is off, and the lower transistor D6 for phase C is off, allowing current to flow. This achieves the locking phase being open (phase A) and the balancing phases (phases B and C) grounded. Maximum resistance is applied to the steering wheel's rotation direction. Lock the steering wheel at its maximum rotation angle. .

[0083] Figure 6 A schematic diagram of a specific implementation of the steer-by-wire system function control method provided in this application. Figure 4 In another specific implementation, such as Figure 6 As shown, the road feel simulator collects the resistance applied to the steering wheel in real time. ,when When the steering wheel's rotation angle is less than its maximum rotation angle, the road feel simulator exits the motor phase lock-up mode. This ensures that the motor lock-up mode works properly.

[0084] Figure 7 A schematic diagram of a specific implementation of the steer-by-wire system function control method provided in this application. Figure 5 In one specific embodiment, the steer-by-wire system function control method provided in this application further includes: if the difference between the current tire turning angle and the maximum tire turning angle is detected to be less than a second preset value, controlling the tire response steering speed of the vehicle to decrease; wherein the magnitude of the tire response steering speed is inversely proportional to the magnitude of the current tire turning angle of the vehicle.

[0085] The determination of the second preset value needs to provide sufficient buffer when the vehicle's current tire steering angle is close to its maximum turning angle, to prevent oversteer or sudden steering changes and avoid potential loss of control risks. By setting an appropriate second preset value, the road feel simulator can adopt a speed reduction response strategy before the end position of the steering actuator motor when the tire steering angle approaches its limit, gradually reducing the tire's response steering speed, making the vehicle's steering more controllable and smooth. Therefore, the setting of the second preset value needs to comprehensively consider the vehicle's dynamic characteristics, the driver's operating habits, and safety requirements, striving to be set as a value that can effectively reduce steering speed when approaching the tire's maximum turning angle, thereby achieving optimal vehicle handling and safety performance.

[0086] Optionally, the range of the second preset value can be set to: Specifically, the value can be 5, 10, 20, 25, 30, etc., which means the current tire rotation angle reaches... , , , or At that time, the road feel simulator controls the vehicle's tire response steering speed to begin to decrease.

[0087] Specifically, such as Figure 7 As shown, the road feel simulator obtains the position information of the rack of the steering actuator motor in real time through the vehicle's communication bus, that is, based on the real-time obtained wheel rotation angle. ,when Reaching the deceleration point hour, (That is, the second preset value is 10), meaning that the vehicle's current tire angle is close to the maximum wheel rotation angle. The road feel simulator employs a speed reduction response strategy before the end position of the steering actuator motor, controlling the tire response steering speed to decrease, thereby reducing the impact of the rack on the steering gear end when the rack rapidly reaches its end. It should be noted that the second preset value of 10 degrees here is merely an example and is not specifically limited in this application. In actual implementation, the second preset value needs to be adjusted appropriately according to the actual situation. The magnitude of the tire response steering speed is inversely proportional to the magnitude of the vehicle's current tire turning angle; that is, the larger the current tire turning angle, the smaller the tire response steering speed, until the vehicle's current tire turning angle reaches its maximum rotation angle. The tire response steering speed decreased to 0, and the vehicle came to a smooth stop.

[0088] In the above method, by setting a second preset value, the system can effectively control the reduction of tire response steering speed when the vehicle's current tire steering angle approaches its maximum turning angle. This method provides sufficient buffering to prevent oversteering or sudden steering changes, thereby avoiding potential loss of control risks.

[0089] The steer-by-wire system control method provided in this application involves a road feel simulator applying resistance to the direction of steering wheel rotation based on real-time data of the steering wheel's rotation angle and a set maximum steering wheel rotation angle. This resistance controls the steering wheel's rotation and alerts the driver that the steering wheel is approaching its limits. Simultaneously, an H-bridge control circuit locks the phase of the road feel simulator motor, ensuring the steering wheel is locked when it reaches its maximum rotation angle, preventing over-rotation. When the vehicle's tires approach their maximum rotation angle, the system reduces the tire's steering response speed to minimize the impact of the rack on the steering gear end. This method achieves precise control of the steering wheel's rotation, keeping it within a reasonable range. It simplifies the steering wheel rotation range limitation scheme in steer-by-wire systems and is suitable for the development and application of modern intelligent driving systems.

[0090] Figure 8 This application provides an overall flowchart of a functional control method for a steer-by-wire system, as shown in the following diagram. Figure 8 As shown, the main functional control methods of this steer-by-wire system include:

[0091] S801. Collect the core parameters of the current vehicle and calculate the maximum rotation angle of the steering wheel and the maximum rotation angle of the wheel corresponding to the rack end position of the vehicle steering actuator motor.

[0092] S802: Real-time acquisition of the current wheel rotation angle. When the rotation angle approaches the maximum wheel rotation angle, the road feel simulator adopts a speed reduction response strategy at the end position of the steering actuator motor to control the tire response steering speed of the vehicle to decrease.

[0093] S803: Real-time acquisition of the current steering wheel rotation angle. When the rotation angle reaches the maximum steering wheel rotation angle, it enters the motor phase lock-up mode.

[0094] S804: Real-time acquisition of the resistance applied to the steering wheel; when the steering wheel rotation angle is less than the set rotation angle, exit the motor phase lock-up mode.

[0095] Specifically, in response to user input, the system collects the vehicle's core parameters and calculates the maximum steering wheel rotation angle corresponding to the rack end position LE of the vehicle's steering actuator motor. and the maximum rotation angle of the wheel The road feel simulator collects the current wheel rotation angle in real time. ,when near At this time, the road feel simulator employs a speed reduction response strategy before the steering actuator motor reaches its end position, controlling the vehicle's tire response steering speed to decrease and prevent the rack from impacting the steering actuator motor's end. The road feel simulator also collects the current steering wheel rotation angle in real time. ,when At this time, the road feel simulator enters motor phase lock mode, locking the steering wheel's rotation angle at its maximum position. The road feel simulator collects the resistance applied to the steering wheel in real time. ,when When the steering wheel rotation angle is less than the set rotation angle, the road feel simulator exits the motor phase lock-up mode.

[0096] The steer-by-wire system function control method of this application embodiment collects and analyzes the vehicle's core parameters in real time using a road feel simulator. Based on the wheel rotation angle, steering wheel rotation angle, and the resistance applied to the steering wheel, the road feel simulator adopts a corresponding forward deceleration response strategy at the end of the steering actuator motor, applies resistance in the direction of steering wheel rotation, and uses a motor phase lock-up mode. This method not only improves the safety and reliability of the vehicle steering system but also enhances the driver's road feel experience, providing smoother and more controllable steering operation. By precisely controlling the steering wheel to rotate within a reasonable range, the limitation on the steering wheel's rotation range in the steer-by-wire system is simplified, effectively reducing mechanical wear and energy loss, and improving the overall system efficiency and response speed.

[0097] Figure 9 A schematic diagram of the structure of a steer-by-wire system functional control device provided in this application is shown below. Figure 9As shown, the steer-by-wire system function control device 90 provided in this embodiment includes:

[0098] The first processing module 901 is used to collect the steering wheel angle data of the vehicle in real time;

[0099] The second processing module 902 is used to control the rotation of the steering wheel based on the steering wheel angle and the maximum steering wheel rotation angle; wherein, the maximum steering wheel rotation angle is determined based on the maximum wheel rotation angle and transmission ratio parameters of the vehicle.

[0100] In one possible implementation, the second processing module 902 is specifically used for:

[0101] If the angle difference between the turning angle and the maximum turning angle of the steering wheel is less than the first preset value, resistance is applied in the direction of steering wheel rotation, and the magnitude of the resistance is proportional to the turning angle.

[0102] In another possible implementation, the steer-by-wire system function control device 90 further includes:

[0103] The third processing module 903 is used to lock the rotation of the steering wheel if the turning angle reaches the maximum rotation angle of the steering wheel;

[0104] The fourth processing module 904 is used to reduce the resistance applied to the steering wheel to zero if the steering wheel center position is detected;

[0105] The fifth processing module 905 is used to calculate the product of the maximum wheel rotation angle and the transmission ratio parameter to obtain the maximum steering wheel rotation angle.

[0106] The sixth processing module 906 is used to control the tire response steering speed of the vehicle to decrease when the difference between the current tire turning angle and the maximum tire turning angle is less than a second preset value; wherein the magnitude of the tire response steering speed is inversely proportional to the magnitude of the current tire turning angle of the vehicle.

[0107] In one possible implementation, the third processing module 903 is specifically used for:

[0108] By applying a preset maximum resistance to the direction of steering wheel rotation, the rotation of the steering wheel can be locked.

[0109] The steer-by-wire system function control device provided in this embodiment can execute the method provided in the above method embodiment. Its implementation principle and technical effect are similar, and will not be described in detail here.

[0110] Figure 10 This is a schematic diagram of the structure of a road feel simulator provided in this application. Figure 10As shown, the road feel simulator 100 provided in this embodiment includes at least one processor 1001 and a memory 1002. Optionally, the road feel simulator 100 further includes a communication component 1003. The processor 1001, memory 1002, and communication component 1003 are connected via a bus 1004.

[0111] In a specific implementation, at least one processor 1001 executes computer execution instructions stored in memory 1002, causing at least one processor 1001 to perform the above-described method.

[0112] The specific implementation process of processor 1001 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0113] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0114] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage device.

[0115] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0116] This application also provides a vehicle, including the main structure of the vehicle and the aforementioned road feel simulator, which implements the above-described method when executed by a processor.

[0117] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the above-described method.

[0118] The aforementioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random-Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read-Only Memory (EPROM), Programmable Read-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0119] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an application-specific integrated circuit (ASIC). Alternatively, the processor and the readable storage medium can exist as discrete components in the device.

[0120] The division of units is merely a logical functional division; in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0121] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0122] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0123] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0124] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0125] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A method for controlling the function of a steer-by-wire system, characterized in that, A road feel simulator applied to vehicles, the method comprising: Real-time acquisition of steering wheel angle data of the vehicle; The steering wheel rotation is controlled based on the steering wheel angle and the maximum steering wheel rotation angle. The maximum steering wheel rotation angle is determined by calculating the product of the maximum wheel rotation angle and the transmission ratio parameter. The maximum wheel rotation angle is obtained by consulting the wheel-rack relationship table, which describes the mapping relationship between the wheel angle and the rack position of the steering actuator motor. The maximum wheel rotation angle corresponds to the wheel angle when the rack of the steering actuator motor is at its end position. The step of controlling the rotation of the steering wheel based on the steering wheel's turning angle and maximum steering wheel rotation angle includes: If the angle difference between the turning angle and the maximum turning angle of the steering wheel is less than a first preset value, resistance is applied in the direction of steering wheel rotation, and the magnitude of the resistance is proportional to the size of the turning angle. If the turning angle reaches the maximum turning angle of the steering wheel, the road feel simulator is controlled to enter the motor phase lock mode. By applying a preset maximum resistance to the steering wheel rotation direction, the rotation of the steering wheel is locked. The motor phase lock mode controls the H-bridge circuit of the road feel simulator to supply a specific current to the stator winding of the permanent magnet synchronous motor, so that the rotor is kept in a position consistent with the magnetic field under the action of a fixed magnetic field, thereby achieving the application of the preset maximum resistance to the steering wheel rotation direction. The method further includes: When the difference between the current tire rotation angle and the maximum tire rotation angle of the vehicle is detected to be less than a second preset value, the tire response steering speed of the vehicle is reduced. The tire response steering speed is inversely proportional to the current tire steering angle of the vehicle.

2. The method according to claim 1, characterized in that, The method further includes: If the steering wheel center position is detected, the resistance applied to the steering wheel will be reduced to zero.

3. A function control device for a steer-by-wire system, characterized in that, Road feel simulators for vehicles include: The first processing module is used to collect the steering wheel angle data of the vehicle in real time; The second processing module is used to control the rotation of the steering wheel based on the steering wheel angle and the maximum steering wheel rotation angle; wherein, the maximum steering wheel rotation angle is determined by calculating the product of the maximum wheel rotation angle and the transmission ratio parameter, and the maximum wheel rotation angle is obtained by querying the wheel-rack relationship table, which describes the mapping relationship between the wheel angle and the rack position of the steering actuator motor, and the maximum wheel rotation angle corresponds to the wheel angle when the rack of the steering actuator motor is at the end position; The second processing module is specifically used to apply resistance to the steering wheel rotation direction if the angle difference between the turning angle and the maximum steering wheel rotation angle is less than a first preset value, wherein the magnitude of the resistance is proportional to the size of the turning angle; If the turning angle reaches the maximum turning angle of the steering wheel, the road feel simulator is controlled to enter the motor phase lock mode. By applying a preset maximum resistance to the steering wheel rotation direction, the rotation of the steering wheel is locked. The motor phase lock mode controls the H-bridge circuit of the road feel simulator to supply a specific current to the stator winding of the permanent magnet synchronous motor, so that the rotor is kept in a position consistent with the magnetic field under the action of a fixed magnetic field, thereby achieving the application of the preset maximum resistance to the steering wheel rotation direction. The sixth processing module is used to control the tire response steering speed of the vehicle to decrease when the difference between the current tire turning angle and the maximum tire turning angle of the vehicle is less than a second preset value; wherein the magnitude of the tire response steering speed is inversely proportional to the magnitude of the current tire turning angle of the vehicle.

4. A road feel simulator, characterized in that, include: Memory, processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory, causing the processor to perform the method as described in any one of claims 1-2.

5. A vehicle, characterized in that, include: The main structure of the vehicle and the road feel simulator as described in claim 4.

6. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method as described in any one of claims 1-2.

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