A distributed steering system and an electric vehicle

Abstract

This application provides a distributed steering system and an electric vehicle, applicable to the field of electric vehicle technology. The distributed steering system includes two actuators and two controllers. Each controller includes a controller housing and a control circuit board fixed within the controller housing. Each controller housing is used to fix a communication interface, which includes a public CAN communication terminal and a private CAN communication terminal. The public CAN communication terminal is used to connect the control circuit board and to connect to a domain controller via a public CAN line. The private CAN communication terminal is used to connect the control circuit board and to connect to another controller housing via a private CAN line. This establishes dual communication channels between the domain controller and the controller, as well as between the two controllers, providing physical-level communication redundancy for the steering system and significantly improving the communication reliability and safety of the steering system.

Description

Technical Field

[0001] This application relates to the field of electric vehicle technology, and more particularly to a distributed steering system and an electric vehicle. Background Technology

[0002] Distributed steering systems have been extensively researched and applied in recent years, particularly in rear-wheel steering or four-wheel independent steering for electric vehicles. In a distributed steering system, each controller independently receives steering angle commands from the upper-level domain controller and controls the steering of the corresponding wheels. When communication between the controller and the domain controller fails, it can lead to loss of control of the steering system or a single wheel, posing a significant safety hazard. Summary of the Invention

[0003] This application provides a distributed steering system and an electric vehicle. By integrating a public CAN terminal and a private CAN terminal on each controller housing, a dual communication channel is constructed between domain controllers and between two controllers, thereby improving the communication reliability and safety of the steering system.

[0004] In a first aspect, embodiments of this application provide a distributed steering system, which includes two actuators and two controllers. The two controllers are used to control the two actuators to drive the two coaxial wheels of an electric vehicle to turn according to the turning angle command of the domain controller. Each controller includes a controller housing and a control circuit board fixed in the controller housing. Each controller is used to receive the turning angle command of the domain controller through the control circuit board and control the actuator.

[0005] Each controller housing is fixed to the actuator housing. Each controller housing is used to fix the communication interface, which includes a public CAN communication terminal and a private CAN communication terminal. One end of the public CAN communication terminal is used to connect to the control circuit board, and the other end of the public CAN communication terminal is used to connect to the domain controller through the public CAN line. One end of the private CAN communication terminal is used to connect to the control circuit board, and the other end of the private CAN communication terminal is used to connect to the communication interface of another controller housing through the private CAN line.

[0006] In this embodiment, by integrating a public CAN terminal and a private CAN terminal on each controller housing, dual communication channels are constructed between domain controllers and between two controllers. The public CAN line between domain controllers enables centralized command issuance of steering instructions for each wheel, achieving distributed high-precision control of two coaxial wheels. The private CAN line between controllers establishes a direct, low-latency physical communication channel between them. The two controllers can exchange their real-time status at a higher frequency and with lower latency through the private CAN line, enhancing the synchronization of the two coaxial wheels. Simultaneously, the dual communication channels provide physical-level communication redundancy for the steering system. When communication between any controller and the domain controller's public CAN line fails, the other controller can act as a communication bridge, maintaining command reception and signal reporting for the failed controller via the private CAN line, thereby significantly improving the communication reliability and safety of the steering system.

[0007] In one embodiment of the first aspect, two controller housings are fixed to opposite sides of the housings of two actuators so that the proprietary CAN communication terminals on the two controller housings are directly connected to each other via proprietary CAN lines.

[0008] In this embodiment, by fixing the two controller housings to the opposite side of the two actuator housings, the two private CAN communication terminals can be directly connected to each other through a shorter private CAN line, which greatly shortens the physical distance of the private communication link between the two controllers. This not only reduces wiring costs and complexity, but also reduces the risk of communication failures caused by vibration and wear of the wiring harness, enabling more stable and reliable transmission of information between the two controllers.

[0009] In one embodiment of the first aspect, when the domain controller communicates with both controllers via the public CAN line without failure, each controller receives the corresponding turning command from the domain controller and sends the actual turning signal to the domain controller via the public CAN line.

[0010] In this embodiment, when the domain controller communicates with both controllers via the public CAN line without failure, each controller independently receives commands and reports signals to the domain controller via the public CAN bus. This direct communication fully utilizes the advantages of the distributed architecture, minimizes the path for command reception and signal reporting, reduces information transmission latency, avoids introducing unnecessary private CAN communication load when there is no fault, and ensures the efficient operation of the steering system under normal conditions.

[0011] In one embodiment of the first aspect, the two controllers include a first controller and a second controller; when the domain controller communicates with both controllers via a public CAN line without failure, the first controller simultaneously receives a first turning command from the domain controller via a public CAN line and a first turning command from the second controller via a private CAN line; the second controller simultaneously receives a second turning command from the domain controller via a public CAN line and a second turning command from the first controller via a private CAN line.

[0012] In this embodiment, when the domain controller communicates with both controllers via the public CAN line without failure, each controller obtains the same steering command through two independent channels: directly receiving via the public CAN and forwarding via the private CAN through another controller. This provides communication redundancy for the steering system under normal conditions. Furthermore, by comparing the two steering commands obtained from the two independent channels, errors on any communication line (such as bit flips or data packet loss) or errors in the controller itself can be detected instantly. This enables real-time and seamless monitoring of the steering system's communication, improving the communication security and reliability of the steering system.

[0013] In one embodiment of the first aspect, when the domain controller communicates with both controllers via the public CAN line without failure, the first controller simultaneously sends a first actual angle signal to the domain controller via the public CAN line and to the second controller via the private CAN line, and the second controller sends the received first actual angle signal to the domain controller via the public CAN line.

[0014] In this embodiment, when the domain controller communicates with both controllers via the public CAN line without failure, each controller sends the same actual steering angle signal to the domain controller through two independent channels: one via the public CAN line and the other via the private CAN line forwarded by the other controller. This provides communication redundancy for the steering system under normal conditions. Furthermore, by comparing the two actual steering angle signals obtained from the two independent channels, errors on any communication line (such as bit flips or data packet loss) or errors in the controller itself can be detected instantly. This enables real-time and imperceptible monitoring of the steering system's communication, improving the communication safety and reliability of the steering system.

[0015] In one embodiment of the first aspect, when the domain controller fails to communicate with the first controller via the public CAN line but does not fail to communicate with the second controller via the public CAN line, the second controller receives the turning command sent by the domain controller via the public CAN line and sends the turning command received from the domain controller to the first controller via the private CAN line.

[0016] In this embodiment, when the domain controller fails to communicate with one controller via the public CAN line but communicates normally with the other controller, the steering system can directly activate the redundancy mode. The controller with normal communication acts as a proxy, forwarding the steering commands of the domain controller to the controller on the faulty side via the private CAN line. This ensures that the steering function of both wheels is not lost when a communication failure occurs, guaranteeing the continuous working capability of the steering system under fault conditions. It avoids the loss of control of the entire steering system or a single wheel due to a single point of communication failure, thus improving the safety and reliability of the steering system.

[0017] In one embodiment of the first aspect, the second controller receives a first steering angle command and a second steering angle command sent by the domain controller via a public CAN line, controls the steering of the corresponding wheel according to the second steering angle command, and sends the first steering angle command to the first controller via a private CAN line; after receiving the first steering angle command, the first controller controls the corresponding actuator to drive the corresponding wheel steering according to the first steering angle command.

[0018] In this embodiment, when the domain controller fails to communicate with one controller via the public CAN line but communicates normally with the other controller, the domain controller sends the steering angle commands (first steering angle command and second steering angle command) of both wheels to the controller with normal communication. This controller, while executing its own steering commands, can accurately forward the steering commands of the faulty controller to the faulty controller via its private CAN, ensuring that the steering function of the faulty controller is not interrupted, thus achieving redundant control of the steering system. Simultaneously, this centralized receiving and distributing execution mode allows the faulty controller to receive steering angle commands as it would during normal operation without changing any logic, reducing operational complexity and ensuring the synchronization of steering commands for the two coaxial wheels, avoiding abnormal vehicle operation due to command reception delays.

[0019] In one embodiment of the first aspect, before the second controller sends a turn command from the domain controller to the first controller via a private CAN line, the second controller receives an enable signal from the first controller via a private CAN line.

[0020] In this embodiment, if the domain controller fails to communicate with one controller via the public CAN line but communicates normally with another controller, the normally communicating controller must first receive an enable signal from the faulty controller via its private CAN link before forwarding the turning command to the faulty controller. This signal indicates that the faulty controller itself has no verification faults (such as internal short circuits or power failures) and is ready to receive turning commands via its private CAN line. This avoids the second controller sending turning commands to the faulty controller even when the faulty controller itself has a serious fault, preventing potential safety risks or invalid operations and improving the reliability and safety of the steering system.

[0021] In one embodiment of the first aspect, when the domain controller fails to communicate with the first controller via the public CAN line but does not fail to communicate with the second controller via the public CAN line, the first controller sends an actual turning angle signal to the second controller via a private CAN line, and the second controller sends the actual turning angle signal received from the first controller to the domain controller via the public CAN line.

[0022] In this embodiment, when the domain controller fails to communicate with one controller via the public CAN line but communicates normally with the other controller, the steering system can directly activate the redundancy mode. The controller with normal communication acts as a proxy, reporting the actual steering angle signal that the faulty controller cannot directly send to the domain controller to the domain controller via the private CAN line. This ensures that the actual steering angle of both wheels can be fed back to the domain controller when a communication failure occurs, avoiding control errors in the domain controller due to missing information caused by a single point of communication failure, and improving the safety and reliability of the steering system.

[0023] In one embodiment of the first aspect, when the communication failure between the domain controller and the first controller via the public CAN line is recovered within the target period, each controller receives a turning command from the domain controller and sends an actual turning signal to the domain controller via the public CAN line.

[0024] In this embodiment, once the communication failure between the domain controller and the fault-side controller via the public CAN line is repaired and stably restored within a target period (i.e., a preset, securely authenticated recovery confirmation time), the steering system can automatically switch from redundant mode back to normal independent communication mode. This ensures that the steering system does not remain in a fault-handling state for an extended period; once the fault disappears, it resumes normal, efficient operation, avoiding continuous resource consumption in redundant mode. Simultaneously, setting a target period prevents frequent switching of communication channels, ensuring the stability of the steering system's communication.

[0025] Secondly, embodiments of this application provide an electric vehicle, which includes a distributed steering system and two coaxial wheels. The distributed steering system includes two actuators and two controllers. The two controllers are used to control the two actuators to drive the two coaxial wheels of the electric vehicle to turn according to the steering angle command of the domain controller. Each controller includes a controller housing and a control circuit board fixed in the controller housing. Each controller is used to receive the steering angle command of the domain controller through the control circuit board and control the actuators, wherein: Each controller housing is fixed to the actuator housing. Each controller housing is used to fix the communication interface, which includes a public CAN communication terminal and a private CAN communication terminal. One end of the public CAN communication terminal is used to connect to the control circuit board, and the other end of the public CAN communication terminal is used to connect to the domain controller through the public CAN line. One end of the private CAN communication terminal is used to connect to the control circuit board, and the other end of the private CAN communication terminal is used to connect to the communication interface of another controller housing through the private CAN line.

[0026] In one embodiment of the second aspect, the two controllers include a first controller and a second controller; when the domain controller fails to communicate with the first controller via the public CAN line but does not fail to communicate with the second controller via the public CAN line, the second controller receives the turning command sent by the domain controller via the public CAN line and sends the turning command received from the domain controller to the first controller via the private CAN line.

[0027] In one embodiment of the second aspect, when the domain controller fails to communicate with the first controller via the public CAN line but does not fail to communicate with the second controller via the public CAN line, the first controller sends the actual turning angle signal to the second controller via the private CAN line, and the second controller sends the actual turning angle signal received from the first controller to the domain controller via the public CAN line.

[0028] The supplementary information and technical effects of the solution provided in the second aspect above can be found in the corresponding explanation in the first aspect, and will not be repeated here. Attached Figure Description

[0029] Figure 1 A schematic diagram of an electric vehicle provided in an embodiment of this application is shown; Figure 2 A schematic diagram of a distributed steering system provided in an embodiment of this application is shown; Figure 3 This paper shows a schematic diagram of the structure of a distributed steering system provided in an embodiment of the present application; Figure 4 A schematic diagram of the communication architecture of a distributed steering system provided in an embodiment of this application is shown; Figure 5 This paper shows a schematic diagram of another distributed steering system provided in an embodiment of the present application; Figure 6 A schematic diagram illustrating the communication process of a distributed steering system provided in an embodiment of this application is shown; Figure 7 A schematic diagram illustrating the communication process of another distributed steering system provided in an embodiment of this application is shown; Figure 8 A schematic diagram illustrating the communication process of another distributed steering system provided in an embodiment of this application is shown; Figure 9 A schematic diagram illustrating the communication process of another distributed steering system provided in an embodiment of this application is shown; Figure 10 A schematic diagram of the communication process of another distributed steering system provided in an embodiment of this application is shown. Detailed Implementation

[0030] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0031] The use of prefixes such as "first" and "second" in this application embodiment is solely for distinguishing different descriptive objects and does not limit the position, order, priority, quantity, or content of the described objects. The use of ordinal numbers and other prefixes to distinguish descriptive objects in this application embodiment does not constitute a limitation on the described objects. The description of the described objects is found in the claims or the context of the embodiments, and the use of such prefixes should not constitute unnecessary restrictions.

[0032] In a distributed steering system, each controller independently receives steering commands from the upper-level domain controller and controls the steering of the corresponding wheels. When communication between the controller and the domain controller fails, the controller on the faulty side will not be able to receive steering commands from the domain controller, which may lead to loss of control of the steering system or one side of the wheels, posing a significant safety hazard.

[0033] In view of this, embodiments of this application provide a distributed steering system and an electric vehicle. The distributed steering system includes two actuators and two controllers. Each controller includes a controller housing and a control circuit board fixed in the controller housing. Each controller housing is used to fix a communication interface. The communication interface includes a public CAN communication terminal and a private CAN communication terminal. One end of the public CAN communication terminal is used to connect to the control circuit board, and the other end of the public CAN communication terminal is used to connect to a domain controller through a public CAN line. One end of the private CAN communication terminal is used to connect to the control circuit board, and the other end of the private CAN communication terminal is used to connect to the communication interface of the other controller housing through a private CAN line. This establishes a dual communication channel between the domain controller and the controller, as well as between the two controllers, providing physical-level communication redundancy for the steering system and significantly improving the communication reliability and safety of the steering system.

[0034] See Figure 1 , Figure 1 A schematic diagram of an electric vehicle provided in an embodiment of this application is shown. (As shown) Figure 1 As shown, the electric vehicle 100 includes a rear-wheel steering system 110, a front-wheel steering system 120, a domain controller 130, and a power battery 140.

[0035] The rear-wheel steering system 110 is used to drive the rear wheels of the electric vehicle 100. The front-wheel steering system 120 is used to drive the front wheels of the electric vehicle 100. The domain controller 130 is used to control the rear-wheel steering system 110 and the front-wheel steering system 120 of the electric vehicle 100. The power battery 140 is used to provide electrical energy to the rear-wheel steering system 110 and the front-wheel steering system 120.

[0036] See Figure 2 , Figure 2 A schematic diagram of a distributed steering system provided in an embodiment of this application is shown. Figure 2 The distributed steering system shown can be either a front-wheel steering system or a rear-wheel steering system.

[0037] like Figure 2 As shown, the distributed steering system 200 includes a controller 211 and actuator 212 for a left wheel on the same axle, and a controller 221 and actuator 222 for a right wheel on the same axle.

[0038] One controller is used to control an actuator to drive a wheel to steer. For example, controller 211 is used to control actuator 212 to drive a left wheel on the same axle to steer.

[0039] During the steering process of the electric vehicle, controllers 212 and 222 receive steering angle commands from domain controller 130 and from the power battery 140 (e.g., Figure 1 The electrical energy (as shown) is used to control actuators 211 and 212 to drive the corresponding wheels to turn according to the direction and angle indicated by the turning command.

[0040] In one embodiment, each actuator includes a steering motor, a reduction mechanism, a lead screw, and a tie rod. The motor shaft of the steering motor is connected to a transmission mechanism. The steering motor drives the lead screw and tie rod to steer the wheels of the electric vehicle after the speed is reduced by the reduction mechanism. The lead screw is, for example, a trapezoidal lead screw, a planetary roller lead screw, or a ball screw. One end of the lead screw is hinged to a tie rod, and the other end of the tie rod is connected to the wheel of the electric vehicle via a steering knuckle.

[0041] During the steering process of the distributed steering system, after the controller receives the steering angle command, it controls the steering motor to output torque. This torque is converted into a suitable steering torque through the transmission mechanism. Then, the converted torque is transmitted to the lead screw, which converts the rotational motion of the steering motor 21 into linear motion axial displacement, which drives the tie rod to axial displacement. Finally, the tie rod drives the wheels to steer.

[0042] The architecture of the embodiments of this application has been described above. The distributed steering system provided by this application will be introduced below with reference to specific embodiments.

[0043] The distributed steering system provided in this application embodiment is described in [reference]. Figure 3 , Figure 3 A schematic diagram of a distributed steering system provided in an embodiment of this application is shown.

[0044] like Figure 3 As shown, the distributed steering system 200 includes two actuators (212 and 222) and two controllers (211 and 221). The two controllers (211 and 221) are used to control the two actuators (212 and 222) to drive the two coaxial wheels of the electric vehicle to turn according to the steering command of the domain controller 130.

[0045] See also Figure 3 Controller 211 includes a controller housing 310 and a control circuit board 320 fixed in the controller housing 310. Controller 211 is used to receive cornering commands from domain controller 130 via the control circuit board 320 and control actuator 212. Controller 221 includes a controller housing 311 and a control circuit board 321 fixed in the controller housing 311. Controller 221 is used to receive cornering commands from domain controller 130 via the control circuit board 321 and control actuator 222.

[0046] in, Figure 3The controller housing shown is lid-shaped. In another embodiment, the controller housing may also be box-shaped. The controller housing may be made of an alloy (e.g., aluminum alloy, magnesium-aluminum alloy), plastic (e.g., reinforced thermoplastic), or a composite material of metal and plastic.

[0047] In one embodiment, each controller housing is fixed to the actuator housing, and each controller housing is used to fix a communication interface, which includes a public CAN communication terminal and a private CAN communication terminal. The public CAN communication terminal is used to connect the control circuit board and the domain controller, and the private CAN communication terminal is used to connect the control circuit board and the communication interface of another controller housing.

[0048] In this way, each controller can communicate with the domain controller as well as with another controller.

[0049] See also Figure 3 Taking the controller 211 that controls one left wheel on the same axle as an example for structural description, in one embodiment, the controller housing 310 is fixed to the actuator housing 330. The controller housing 310 is used to fix the communication interface, which includes a public CAN communication terminal 340 and a private CAN communication terminal 350. One end of the public CAN communication terminal 340 is used to connect to the control circuit board 320, and the other end of the public CAN communication terminal 340 is used to connect to the domain controller 130 through the public CAN line 360. One end of the private CAN communication terminal 350 is used to connect to the control circuit board 320, and the other end of the private CAN communication terminal 350 is used to connect to the communication interface (private CAN communication terminal 351) of another controller housing through the private CAN line 370.

[0050] The actuator housing is primarily used to house and protect the mechanical moving parts of the distributed steering system, including the aforementioned steering motor, transmission mechanism, lead screw, and tie rod. The controller housing is used to protect the control circuit board. The controller housing 310 can be fixed to the actuator housing 330 by a fixed connection (e.g., welding) or a detachable connection (e.g., bolt fastening, snap-fit ​​connection).

[0051] In one embodiment, a direct-plug structure can be used between the private CAN communication terminal 350 and the private CAN communication terminal 351, as well as between the public CAN communication terminal 340 and the domain controller 130. That is, the public CAN line 360 ​​and the private CAN line 370 can be a twisted pair cable bundle. The two ends of the private CAN line 370 are respectively plugged into the two private CAN communication terminals, and the two ends of the public CAN line 360 ​​are respectively plugged into the CAN communication terminal and the communication interface on the domain controller.

[0052] Inside the actuator housing, the control circuit board is connected to the steering motor to transmit power to drive the steering motor to rotate and to transmit signals to sense the rotor position of the steering motor. The two can be connected by directly plugging or soldering the control circuit board to the motor's terminals (PIN pins), or by connecting them through wire harnesses and connectors.

[0053] In one embodiment, the communication interface further includes a sensor terminal, one end of which is used to connect to the control circuit board, and the other end is used to connect to a position detection sensor that detects the displacement of the lead screw.

[0054] In another embodiment, each controller housing is also used to secure a power interface for connecting a power battery to power the control circuit board and the steering motor.

[0055] Correspondingly, the structure related to the controller 212 that controls one right wheel on the same axle is the same as the structure related to the controller 211 that controls one left wheel on the same axle. For example... Figure 3 As shown, the controller housing 311 is fixed to the actuator housing 331. The controller housing 311 is used to fix the communication interface, which includes a public CAN communication terminal 341 and a private CAN communication terminal 351. One end of the public CAN communication terminal 341 is used to connect to the control circuit board 321, and the other end of the public CAN communication terminal 341 is used to connect to the domain controller 130 through the public CAN line 360. One end of the private CAN communication terminal 351 is used to connect to the control circuit board 321, and the other end of the private CAN communication terminal 351 is used to connect to the communication interface (private CAN communication terminal 350) of another controller housing through the private CAN line 370.

[0056] in, Figure 3 The relative positions of the public CAN communication terminal 340 and private CAN communication terminal 350, public CAN communication terminal 341 and private CAN communication terminal 351 shown are merely exemplary.

[0057] This enables public CAN communication between each controller and the domain controller, as well as private CAN communication with another controller.

[0058] For ease of understanding, see Figure 4 , Figure 4 A schematic diagram of the communication architecture of a distributed steering system provided in an embodiment of this application is shown.

[0059] like Figure 4 As shown, the domain controller communicates with the two controllers via a public CAN, and the two controllers communicate with each other via a private CAN.

[0060] In this embodiment, by integrating a public CAN terminal and a private CAN terminal on each controller housing, dual communication channels are constructed between domain controllers and between two controllers. The public CAN line between domain controllers enables centralized command issuance of steering instructions for each wheel, achieving distributed high-precision control of two coaxial wheels. The private CAN line between controllers establishes a direct, low-latency physical communication channel between them. The two controllers can exchange their real-time status at a higher frequency and with lower latency through the private CAN line, enhancing the synchronization of the two coaxial wheels. Simultaneously, the dual communication channels provide physical-level communication redundancy for the steering system. When communication between any controller and the domain controller's public CAN line fails, the other controller can act as a communication bridge, maintaining command reception and signal reporting for the failed controller via the private CAN line, thereby significantly improving the communication reliability and safety of the steering system.

[0061] In one embodiment, two controller housings are fixed to opposite sides of the housings of two actuators so that the proprietary CAN communication terminals on the two controller housings are directly connected to each other via proprietary CAN lines.

[0062] In this way, the two private CAN communication terminals can be connected through a private CAN line, and the wiring does not need to go around the two steering motors and two controllers, which greatly reduces the length of the private CAN line.

[0063] For ease of understanding, see Figure 5 , Figure 5 A schematic diagram of another distributed steering system provided in an embodiment of this application is shown.

[0064] like Figure 5 As shown, the controller housing 310 is fixed to the actuator housing 330 on the side facing the actuator housing 331 (i.e., the opposing side). The controller housing 311 is fixed to the actuator housing 331 on the side facing the actuator housing 330 (i.e., the opposing side). In other words, the two controller housings are respectively mounted on the inner sides of the two actuator housings facing each other.

[0065] Based on the aforementioned opposing arrangement, the proprietary CAN communication terminal 350 on the controller housing 310 and the proprietary CAN communication terminal 351 on the controller housing 311 are spatially close to each other, and their interfaces face each other. The proprietary CAN communication terminal 350 and the proprietary CAN communication terminal 351 can be directly connected to each other via a very short proprietary CAN line 370.

[0066] In one embodiment, the length of the private CAN line 370 can be designed to be the minimum physical distance between two private CAN communication terminals.

[0067] In one embodiment, the two private CAN communication terminals can adopt a matching male and female connector structure. When the two controller housings are installed in place, the two private CAN communication terminals automatically plug and match to achieve direct physical connection. At this time, the private CAN line 370 is integrated inside the connector, and no external independent wiring harness is required.

[0068] In this embodiment, by fixing the two controller housings to the opposite side of the two actuator housings, the two private CAN communication terminals can be directly connected to each other through a shorter private CAN line, which greatly shortens the physical distance of the private communication link between the two controllers. This not only reduces wiring costs and complexity, but also reduces the risk of communication failures caused by vibration and wear of the wiring harness, enabling more stable and reliable transmission of information between the two controllers.

[0069] The following provides a detailed description of the communication process between the two controllers and between the controller and the domain controller.

[0070] In one embodiment, when the domain controller communicates with both controllers via the public CAN line without failure, each controller receives the corresponding turning command from the domain controller and sends the actual turning signal to the domain controller via the public CAN line.

[0071] In one embodiment, the controller also receives upper-layer system information from the domain controller via a public CAN line, intended to inform the controller of the current control mode, such as manual takeover or intelligent driving; the current functional mode, such as automatic parking or highway navigation; and the current coordination and safety mode, such as whether the system is healthy or in a degraded state.

[0072] After receiving information from the upper-level system, the controller can determine whether to trust and execute the received steering command based on the specific information indicated by the upper-level system. If execution is allowed, the controller controls the corresponding actuator to steer the wheels according to the direction and angle indicated by the steering command; if execution is not allowed, the steering command is ignored and the system switches back to the default safe posture, such as controlling the wheels to return to center.

[0073] In one embodiment, each controller also sends controller status information to the domain controller via a public CAN line. The controller status information includes controller mode information, such as initialization mode, calibration mode, or fault mode; execution status and limit information, such as whether it is moving towards the angle indicated by the cornering command, whether it has reached the target, whether it is out of tolerance, and whether it has reached the mechanical or software limit; system health and safety status, such as whether it is ready to respond to the cornering command, whether it is in a safe state (such as locked, return to center, or closed), and internal error codes.

[0074] After receiving signals from each controller, the domain controller can replan the control of the corresponding wheel based on the information indicated by the received signals.

[0075] For ease of understanding, see Figure 6 , Figure 6 A schematic diagram of the communication process of a distributed steering system provided in an embodiment of this application is shown.

[0076] like Figure 6 As shown, both controllers receive cornering commands and upper-level system information from the domain controller, as well as send actual cornering signals and controller status information to the domain controller.

[0077] In this embodiment, when the domain controller communicates with both controllers via the public CAN line without failure, each controller independently receives commands and reports signals to the domain controller via the public CAN bus. This direct communication fully utilizes the advantages of the distributed architecture, minimizes the path for command reception and signal reporting, reduces information transmission latency, avoids introducing unnecessary private CAN communication load when there is no fault, and ensures the efficient operation of the steering system under normal conditions.

[0078] For ease of description, the two controllers will be referred to as the first controller (e.g., the aforementioned controller 211) and the second controller (e.g., the aforementioned controller 221).

[0079] In one embodiment, assuming that the domain controller communicates with both controllers via the public CAN line without failure, the first controller simultaneously receives a first turning command from the domain controller via the public CAN line and from the second controller via the private CAN line; the second controller simultaneously receives a second turning command from the domain controller via the public CAN line and from the first controller via the private CAN line.

[0080] The first controller receives a first steering angle command and controls the steering of the corresponding wheel according to the first steering angle command, while the second controller receives a second steering angle command and controls the steering of the corresponding wheel according to the second steering angle command.

[0081] The first controller receives the first turning command through two channels. In one embodiment, after receiving the first turning command from both channels, the first controller compares and verifies the two received first turning commands. If they match, the first controller executes the first turning command. If they do not match, the first controller determines that a data transmission error has occurred in one channel and triggers a security protection mechanism.

[0082] The security protection mechanisms here include, but are not limited to: ignoring the current turning instruction, maintaining the previous valid instruction, requesting the domain controller to resend the instruction, or controlling the distributed turning system to enter a safe state (such as locking the center).

[0083] Similarly, after the domain controller sends the second turning command to the second controller, the second controller will receive the second turning command through two channels and compare and verify the two second turning commands.

[0084] For ease of understanding, see Figure 7 , Figure 7 A schematic diagram of the communication process of another distributed steering system provided in an embodiment of this application is shown.

[0085] like Figure 7 As shown, the domain controller sends a first turning command and a second turning command to both controller 211 and controller 221. Controller 211 sends the second turning command to controller 221, and controller 221 sends the first turning command to controller 211.

[0086] In this embodiment, when the domain controller communicates with both controllers via the public CAN line without failure, each controller obtains the same steering command through two independent channels: directly receiving via the public CAN and forwarding via the private CAN through another controller. This provides communication redundancy for the steering system under normal conditions. Furthermore, by comparing the two steering commands obtained from the two independent channels, errors on any communication line (such as bit flips or data packet loss) or errors in the controller itself can be detected instantly. This enables real-time and seamless monitoring of the steering system's communication, improving the communication security and reliability of the steering system.

[0087] In one embodiment, when the domain controller communicates with both controllers via the public CAN line without failure, the first controller simultaneously sends a first actual turning angle signal to the domain controller via the public CAN line and to the second controller via the private CAN line. The second controller then sends the received first actual turning angle signal to the domain controller via the public CAN line.

[0088] Wherein, the first actual turning angle signal is the actual turning angle signal of the wheel controlled by the first controller, and the second actual turning angle signal is the actual turning angle signal of the wheel controlled by the second controller.

[0089] The first controller sends a first actual turn signal to the domain controller through two channels. In one embodiment, after the domain controller receives the first actual turn signals from the two channels, it compares and verifies the two received first actual turn signals. If they match, the domain controller issues a new first turn command to the first controller based on the received first actual turn signal. If they do not match, the domain controller determines that a data transmission error has occurred on one channel and triggers a security protection mechanism. This security protection mechanism could be a request for the first controller to resend the first actual turn signal through both channels.

[0090] Similarly, the second controller simultaneously sends the second actual turning angle signal to the domain controller via the public CAN line and to the first controller via the private CAN line. The first controller then sends the received second actual turning angle signal to the domain controller via the public CAN line.

[0091] For ease of understanding, see Figure 8 , Figure 8 A schematic diagram of the communication process of another distributed steering system provided in an embodiment of this application is shown.

[0092] like Figure 8 As shown, controller 211 sends a first actual turning angle signal to both the domain controller and controller 221, and controller 221 sends the received first actual turning angle signal and second actual turning angle signal to the domain controller; controller 221 sends a second actual turning angle signal to both the domain controller and controller 211, and controller 211 sends the received second actual turning angle signal and first actual turning angle signal to the domain controller.

[0093] In this embodiment, when the domain controller communicates with both controllers via the public CAN line without failure, each controller sends the same actual steering angle signal to the domain controller through two independent channels: one via the public CAN line and the other via the private CAN line forwarded by the other controller. This provides communication redundancy for the steering system under normal conditions. Furthermore, by comparing the two actual steering angle signals obtained from the two independent channels, errors on any communication line (such as bit flips or data packet loss) or errors in the controller itself can be detected instantly. This enables real-time and imperceptible monitoring of the steering system's communication, improving the communication safety and reliability of the steering system.

[0094] In one embodiment, when the domain controller fails to communicate with the first controller via the public CAN line but does not fail to communicate with the second controller via the public CAN line, the second controller receives the turning command sent by the domain controller via the public CAN line and sends the turning command received from the domain controller to the first controller via the private CAN line.

[0095] Among them, communication failures between the domain controller and the controller via the CAN line can be data verification failure (E2E failure), communication timeout failure (TimeOut failure), line shutdown failure (BusOff failure), etc.

[0096] E2E faults refer to data transmission failures between the signal sender and receiver, including data tampering, data loss, sequence errors, and excessive delays, which do not directly affect CAN bus communication.

[0097] Timeout failure refers to the receiver not receiving a signal within a preset time, including situations such as the sender crashing or configuration errors.

[0098] BusOff faults refer to internal errors in the CAN line node, which automatically disconnects from the CAN line. These faults can include hardware failures, electromagnetic interference, etc., affecting CAN line communication.

[0099] After ruling out physical layer faults in the CAN line (such as power problems, line breaks, bus short circuits, electromagnetic interference, etc.), you can determine in sequence whether the CAN line has BusOff faults, TimeOut faults, and E2E faults.

[0100] In the event of a communication failure between the domain controller and the first controller via the public CAN line, the second controller can act as a relay station for the cornering command. The domain controller sends the cornering command (i.e., the first cornering command) that needs to be sent to the first controller to the second controller, which then forwards it to the first controller via its private CAN line. In addition, the information forwarded by the second controller also includes the aforementioned upper-layer system information.

[0101] In one embodiment, to ensure that the cornering command received by the first controller via the private CAN line is consistent with the original cornering command issued by the domain controller, the private CAN line can adopt the same communication protocol as the public CAN line and employ a verification mechanism. The verification mechanism could be as follows: the command message sent by the first controller includes an original checksum and a counter; the first controller verifies the consistency upon receipt; the second controller does not modify the data field of the first cornering command before forwarding, only performing message ID conversion or direct routing forwarding; the second controller appends a forwarding timestamp during forwarding, which the first controller uses to determine the timeliness of the command.

[0102] For ease of understanding, see Figure 9 , Figure 9 A schematic diagram of the communication process of another distributed steering system provided in an embodiment of this application is shown.

[0103] like Figure 9 As shown, when the domain controller fails to communicate with controller 211, the domain controller sends a first turning command and a second turning command to controller 221, and then controller 221 forwards the first turning command to controller 211.

[0104] Similarly, in one embodiment, when the domain controller fails to communicate with the second controller via the public CAN line but does not fail to communicate with the first controller via the public CAN line, the first controller receives the turning command sent by the domain controller via the public CAN line and sends the turning command received from the domain controller to the second controller via the private CAN line.

[0105] That is, the two controllers can send each other cornering commands received from the domain controller via a private CAN.

[0106] In this embodiment, when the domain controller fails to communicate with one controller via the public CAN line but communicates normally with the other controller, the steering system can directly activate the redundancy mode. The controller with normal communication acts as a proxy, forwarding the steering commands of the domain controller to the controller on the faulty side via the private CAN line. This ensures that the steering function of both wheels is not lost when a communication failure occurs, guaranteeing the continuous working capability of the steering system under fault conditions. It avoids the loss of control of the entire steering system or a single wheel due to a single point of communication failure, thus improving the safety and reliability of the steering system.

[0107] In one embodiment, if the domain controller fails to communicate with the first controller via the public CAN line but does not fail to communicate with the second controller via the public CAN line, the second controller receives a first steering angle command and a second steering angle command sent by the domain controller via the public CAN line, controls the steering of the corresponding wheels according to the second steering angle command, and sends the first steering angle command to the first controller via the private CAN line. After receiving the first steering angle command, the first controller controls the corresponding actuator to drive the steering of the corresponding wheels according to the first steering angle command.

[0108] Correspondingly, the two actuators include a first actuator and a second actuator. The first controller receives a first turning command and controls the first actuator to execute the first turning command, while the second controller receives a second turning command and controls the second actuator to execute the second turning command accordingly.

[0109] Even if the domain controller fails to communicate with the first controller via the public CAN line, the first controller can still receive the first steering angle command and control the first actuator to drive the corresponding wheel steering according to the first steering angle command.

[0110] Similarly, when the domain controller fails to communicate with the second controller via the public CAN line but does not fail to communicate with the first controller via the public CAN line, the first controller receives the first and second steering angle commands sent by the domain controller via the public CAN line, controls the steering of the corresponding wheels according to the first steering angle command, and sends the second steering angle command to the second controller via the private CAN line; after receiving the second steering angle command, the second controller controls the corresponding actuator to drive the steering of the corresponding wheels according to the second steering angle command.

[0111] In other words, even if the domain controller fails to communicate with any controller via the public CAN line, the controller on the faulty side can still receive the turning command and control the actuator to drive the corresponding wheel to turn according to the turning command.

[0112] In this embodiment, when the domain controller fails to communicate with one controller via the public CAN line but communicates normally with the other controller, the domain controller sends the steering angle commands (first steering angle command and second steering angle command) of both wheels to the controller with normal communication. This controller, while executing its own steering commands, can accurately forward the steering commands of the faulty controller to the faulty controller via its private CAN, ensuring that the steering function of the faulty controller is not interrupted, thus achieving redundant control of the steering system. Simultaneously, this centralized receiving and distributing execution mode allows the faulty controller to receive steering angle commands as it would during normal operation without changing any logic, reducing operational complexity and ensuring the synchronization of steering commands for the two coaxial wheels, avoiding abnormal vehicle operation due to command reception delays.

[0113] In another embodiment, the second controller also sends a second steering angle command to the first controller via a private CAN line to avoid errors in the forwarding of the first steering angle command. The first controller can control the corresponding actuator to drive the corresponding wheel to turn according to the second steering angle command, that is, control the two wheels on the same axle to have the same steering angle and turn together.

[0114] In one embodiment, before the second controller sends a turn command from the domain controller to the first controller via a private CAN line, the second controller receives an enable signal from the first controller via a private CAN line.

[0115] That is, by activating the relevant algorithm inside the second controller through the enable signal, the second controller receives the turning command sent by the domain controller through the public CAN.

[0116] In one scenario, the second controller can receive the first turn command from the domain controller, but will only forward it to the first controller after receiving an enable signal. In another scenario, the second controller can only receive the first turn command from the domain controller after receiving an enable signal.

[0117] In this embodiment, if the domain controller fails to communicate with one controller via the public CAN line but communicates normally with another controller, the normally communicating controller must first receive an enable signal from the faulty controller via its private CAN link before forwarding the turning command to the faulty controller. This signal indicates that the faulty controller itself has no verification faults (such as internal short circuits or power failures) and is ready to receive turning commands via its private CAN line. This avoids the second controller sending turning commands to the faulty controller even when the faulty controller itself has a serious fault, preventing potential safety risks or invalid operations and improving the reliability and safety of the steering system.

[0118] In one embodiment, when the domain controller fails to communicate with the first controller via the public CAN line but does not fail to communicate with the second controller via the public CAN line, the first controller sends the actual turning angle signal to the second controller via the private CAN line, and the second controller sends the actual turning angle signal received from the first controller to the domain controller via the public CAN line.

[0119] The first controller needs to send the actual turning angle signal and the controller status information of the first controller to the domain controller. In the event of a communication failure between the domain controller and the first controller via the public CAN line, the second controller will act as a relay station. The second controller will receive the actual turning angle signal and the controller status information sent by the first controller and forward them to the domain controller.

[0120] Similarly, when the domain controller fails to communicate with the second controller via the public CAN line but does not fail to communicate with the first controller via the public CAN line, the second controller sends the actual turning angle signal to the first controller via the private CAN line, and the first controller sends the actual turning angle signal received from the second controller to the domain controller via the public CAN line.

[0121] For ease of understanding, see Figure 10 , Figure 10 A schematic diagram of the communication process of another distributed steering system provided in an embodiment of this application is shown.

[0122] like Figure 10As shown, when the domain controller fails to communicate with controller 211, controller 211 sends a first actual turning angle signal to controller 221, controller 221 forwards the first actual turning angle signal to the domain controller, and at the same time controller 221 sends a second actual turning angle signal to the domain controller.

[0123] In this embodiment, when the domain controller fails to communicate with one controller via the public CAN line but communicates normally with the other controller, the steering system can directly activate the redundancy mode. The controller with normal communication acts as a proxy, reporting the actual steering angle signal that the faulty controller cannot directly send to the domain controller to the domain controller via the private CAN line. This ensures that the actual steering angle of both wheels can be fed back to the domain controller when a communication failure occurs, avoiding control errors in the domain controller due to missing information caused by a single point of communication failure, and improving the safety and reliability of the steering system.

[0124] In one embodiment, when the communication failure between the domain controller and the first controller via the public CAN line is recovered within the target period, each controller receives the turning command from the domain controller and sends the actual turning signal to the domain controller via the public CAN line.

[0125] The target period refers to the time limit within which the system allows communication to recover after a failure in public CAN communication (such as an interruption in communication between the first controller and the domain controller) so that it can continue to operate normally according to the original control logic without triggering security degradation or fault handling. The target period can be between 50ms and 100ms, or between 20ms and 50ms, etc.

[0126] In one embodiment, when the communication failure between the domain controller and the first controller via the public CAN line is recovered within the target period, the communication status of the two can be changed from "fault" to "running" or "pending verification". After verification is successful, communication between the two via the public CAN line is restored.

[0127] In this embodiment, once the communication failure between the domain controller and the fault-side controller via the public CAN line is repaired and stably restored within a target period (i.e., a preset, securely authenticated recovery confirmation time), the steering system can automatically switch from redundant mode back to normal independent communication mode. This ensures that the steering system does not remain in a fault-handling state for an extended period; once the fault disappears, it resumes normal, efficient operation, avoiding continuous resource consumption in redundant mode. Simultaneously, setting a target period prevents frequent switching of communication channels, ensuring the stability of the steering system's communication.

[0128] This application embodiment also provides an electric vehicle, which includes a distributed steering system and two coaxial wheels. The distributed steering system includes two actuators and two controllers. The two controllers are used to control the two actuators to drive the two coaxial wheels of the electric vehicle to turn according to the steering angle command of the domain controller. Each controller includes a controller housing and a control circuit board fixed in the controller housing. Each controller is used to receive the steering angle command of the domain controller through the control circuit board and control the actuator, wherein: Each controller housing is fixed to the actuator housing. Each controller housing is used to fix the communication interface, which includes a public CAN communication terminal and a private CAN communication terminal. One end of the public CAN communication terminal is used to connect to the control circuit board, and the other end of the public CAN communication terminal is used to connect to the domain controller through the public CAN line. One end of the private CAN communication terminal is used to connect to the control circuit board, and the other end of the private CAN communication terminal is used to connect to the communication interface of another controller housing through the private CAN line.

[0129] In one embodiment, the two controllers include a first controller and a second controller; when the domain controller fails to communicate with the first controller via the public CAN line but does not fail to communicate with the second controller via the public CAN line, the second controller receives the turning command sent by the domain controller via the public CAN line and sends the turning command received from the domain controller to the first controller via the private CAN line.

[0130] In one embodiment, when the domain controller fails to communicate with the first controller via the public CAN line but does not fail to communicate with the second controller via the public CAN line, the first controller sends the actual turning angle signal to the second controller via the private CAN line, and the second controller sends the actual turning angle signal received from the first controller to the domain controller via the public CAN line.

[0131] It is understood that all relevant content involved in the above-described embodiments of the distributed steering system can be referenced in the embodiments of the electric vehicle, and will not be repeated here.

[0132] Finally, it should be noted that the above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A distributed steering system for implementing redundant control, characterized in that, The distributed steering system includes two actuators and two controllers. The two controllers are used to control the two actuators to steer the two coaxial wheels of the electric vehicle according to the steering angle command from the domain controller. Each controller includes a controller housing and a control circuit board fixed within the controller housing. Each controller is used to receive the steering angle command from the domain controller via the control circuit board and control the actuator, wherein: Each controller housing is fixed to the actuator housing. Each controller housing is used to fix a communication interface, which includes a public CAN communication terminal and a private CAN communication terminal. One end of the public CAN communication terminal is used to connect to the control circuit board, and the other end of the public CAN communication terminal is used to connect to the domain controller via a public CAN line. One end of the private CAN communication terminal is used to connect to the control circuit board, and the other end of the private CAN communication terminal is used to connect to the communication interface of another controller housing via a private CAN line.

2. The distributed steering system according to claim 1, characterized in that, The two controller housings are fixed to opposite sides of the housings of the two actuators so that the private CAN communication terminals on the two controller housings are directly connected to each other through the private CAN line.

3. The distributed steering system according to claim 1, characterized in that, The two controllers include a first controller and a second controller; When the domain controller fails to communicate with the first controller via the public CAN line but does not fail to communicate with the second controller via the public CAN line, the second controller receives the turning command sent by the domain controller via the public CAN line and sends the turning command received from the domain controller to the first controller via the private CAN line.

4. The distributed steering system according to claim 3, characterized in that, The second controller receives the first steering angle command and the second steering angle command sent by the domain controller through the public CAN line, controls the steering of the corresponding wheels according to the second steering angle command, and sends the first steering angle command to the first controller through the private CAN line; After receiving the first steering angle command, the first controller controls the corresponding actuator to drive the corresponding wheel to steer according to the first steering angle command.

5. The distributed steering system according to claim 3, characterized in that, Before the second controller sends the cornering command from the domain controller to the first controller via the private CAN line, the second controller receives an enable signal from the first controller via the private CAN line.

6. The distributed steering system according to claim 1, characterized in that, The two controllers include a first controller and a second controller; When the domain controller fails to communicate with the first controller via the public CAN line but does not fail to communicate with the second controller via the public CAN line, the first controller sends the actual turning angle signal to the second controller via the private CAN line, and the second controller sends the actual turning angle signal received from the first controller to the domain controller via the public CAN line.

7. The distributed steering system according to claim 1, characterized in that, When the domain controller communicates with the two controllers via the public CAN line without failure, each controller receives the corresponding turning command from the domain controller and sends the actual turning signal to the domain controller via the public CAN line.

8. The distributed steering system according to claim 1, characterized in that, The two controllers include a first controller and a second controller; When the domain controller communicates with both controllers via the public CAN line without failure, the first controller simultaneously receives the first turning command from the domain controller via the public CAN line and from the second controller via the private CAN line. The second controller simultaneously receives a second turning command from the domain controller via the public CAN line and from the first controller via the private CAN line.

9. The distributed steering system according to claim 1, characterized in that, The two controllers include a first controller and a second controller; When the domain controller communicates with both controllers via the public CAN line without failure, the first controller simultaneously sends a first actual turning angle signal to the domain controller via the public CAN line and to the second controller via the private CAN line. The second controller then sends the received first actual turning angle signal to the domain controller via the public CAN line.

10. The distributed steering system according to any one of claims 3-6, characterized in that, When the communication failure between the domain controller and the first controller via the public CAN line is recovered within the target period, each controller receives the turning command from the domain controller and sends the actual turning signal to the domain controller via the public CAN line.

11. An electric vehicle, characterized in that, The electric vehicle includes a distributed steering system and two coaxial wheels. The distributed steering system includes two actuators and two controllers. The two controllers are used to control the two actuators to drive the two coaxial wheels of the electric vehicle to turn according to the steering angle command of the domain controller. Each controller includes a controller housing and a control circuit board fixed in the controller housing. Each controller is used to receive the steering angle command of the domain controller through the control circuit board and control the actuator, wherein: Each controller housing is fixed to the actuator housing. Each controller housing is used to fix a communication interface, which includes a public CAN communication terminal and a private CAN communication terminal. One end of the public CAN communication terminal is used to connect to the control circuit board, and the other end of the public CAN communication terminal is used to connect to the domain controller via a public CAN line. One end of the private CAN communication terminal is used to connect to the control circuit board, and the other end of the private CAN communication terminal is used to connect to the communication interface of another controller housing via a private CAN line.

12. The electric vehicle according to claim 11, characterized in that, The two controllers include a first controller and a second controller; When the domain controller fails to communicate with the first controller via the public CAN line but does not fail to communicate with the second controller via the public CAN line, the second controller receives the turning command sent by the domain controller via the public CAN line and sends the turning command received from the domain controller to the first controller via the private CAN line.

13. The electric vehicle according to claim 11, characterized in that, The two controllers include a first controller and a second controller; When the domain controller fails to communicate with the first controller via the public CAN line but does not fail to communicate with the second controller via the public CAN line, the first controller sends the actual turning angle signal to the second controller via the private CAN line, and the second controller sends the actual turning angle signal received from the first controller to the domain controller via the public CAN line.

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