Vehicle corner module steering fault redundancy control method, corner module and vehicle

Abstract

The invention relates to the technical field of steer-by-wire, in particular to a vehicle angle module steering fault redundancy control method, an angle module and a vehicle. S2, judging whether the angle module has an electronic fault or not; s3, when it is detected that the angle module has the electronic fault, the steering angle deviation of the wheel of the fault angle module is determined; s4, the feedforward driving torque compensation amount and the feedback driving torque compensation amount of the driving motor are generated, and the total driving torque compensation amount of the driving motor is obtained; s5, according to the total driving torque compensation amount, the wheels of the fault angle module generate longitudinal tire force, and equivalent steering torque around a main pin is formed at the position of the main pin; and meanwhile, the fault angle module is controlled to be switched to a steering angle following mode or a steering angle keeping mode, so that steering redundancy control is achieved. The method has the advantages that under the condition that the kingpin steering executing mechanism fails, steering redundancy can be achieved without adding an additional mechanical steering executing mechanism, and the system safety is improved.

Description

Vehicle corner module steering fault redundancy control method, corner module and vehicle Technical Field

[0001] This invention relates to the field of steer-by-wire technology, and in particular to a method for redundancy control of steering faults in a vehicle's corner module, a corner module, and a vehicle. Background Technology

[0002] With the development of intelligent driving and autonomous driving technologies, steer-by-wire systems are gradually replacing traditional mechanical steering systems. However, existing steer-by-wire systems generally suffer from single-point failure risks. When the kingpin steering motor, reduction gear, or its power supply system fails, the vehicle will lose its steering ability, seriously affecting driving safety. To address this issue, existing technologies typically employ the following solutions: first, setting up dual steering motors or a dual mechanical redundancy structure; second, restoring manual steering through a mechanical emergency connection; and third, restricting the vehicle to a low-speed safety mode after a fault is detected. While these solutions improve system safety to some extent, they still suffer from problems such as complex structure, high cost, increased size and weight, difficult layout, and discontinuous control switching, making it difficult to meet the requirements of small steer-by-wire chassis and autonomous vehicles for high reliability, low cost, and compact design.

[0003] Chinese patent publication number CN119840712A, published on April 18, 2025, entitled "A Steering Control Method and Device for a Four-Wheel Independent Drive and Steering Electric Vehicle," achieves redundant control by coordinating the steering actuators and wheel hub motors through a central controller. However, this method relies on a high-performance central controller and a high-speed communication network, resulting in drawbacks such as complex architecture, single-point failure risk, and difficulty in coordination. Furthermore, for chassis with integrated corner modules, this solution does not fully utilize their core characteristic of independent control, and the control strategy lacks specificity and refinement. Therefore, there is an urgent need to propose a new steering redundancy control scheme that is fast-responding, has a simple architecture, high reliability, and is adaptable to vehicles with corner modules. Summary of the Invention

[0004] Based on this, the present invention aims to provide a vehicle corner module steering fault redundancy control method, corner module and vehicle. When the kingpin steering actuator fails, the longitudinal tire force generated by the drive motor forms an equivalent steering torque at the kingpin, thereby maintaining the basic steering ability of the vehicle, improving the safety and controllability of the vehicle under fault conditions, and avoiding the addition of complex mechanical redundancy structures.

[0005] To achieve the above objectives, the invention provides a vehicle corner module steering fault redundancy control method, comprising the following steps:

[0006] S1: Obtain vehicle driving status information;

[0007] S2: Based on driving status information, determine whether there is an electronic fault in the corner module;

[0008] S3: According to step S2, when an electronic fault is detected in the corner module, the steering angle deviation of the wheel of the faulty corner module is determined based on the driving status information;

[0009] S4: Based on the steering angle deviation, generate the feedforward drive torque compensation amount and feedback drive torque compensation amount of the drive motor of the wheel, and then obtain the total drive torque compensation amount of the drive motor.

[0010] S5: Control the output torque of the drive motor according to the total drive torque compensation amount, so that the wheels of the fault angle module generate longitudinal tire force and form an equivalent steering torque around the kingpin at the kingpin of the angle module; at the same time, control the fault angle module to switch to steering angle following mode or steering angle holding mode to achieve steering redundancy control.

[0011] Furthermore, the driving status information includes: the communication status of the steering mechanism of the angle module, the power supply status of the steering mechanism, the actual steering angle feedback value of the angle module, and the target steering angle command of the angle module.

[0012] Furthermore, in step S5, in the steering angle holding mode, the output torque of the drive motor is controlled to make the longitudinal tire force form an equivalent steering torque at the kingpin, so as to keep the current steering angle unchanged; in the steering angle following mode, the magnitude and direction of the output torque of the drive motor are adjusted according to the deviation between the target steering angle and the actual steering angle, so that the longitudinal tire force forms the target steering torque at the kingpin, thereby realizing steering angle change control.

[0013] Furthermore, in step S5, the brake mechanism of the steering mechanism is triggered to lock the steering mechanism when any of the following conditions are detected: the steering mechanism suffers an irreversible mechanical failure; more than half of the steering mechanisms of all corner modules in the vehicle fail; or the drive motor is unable to make the actual steering angle follow the target steering angle at its maximum output capacity.

[0014] Furthermore, when a steering mechanism failure is detected, the steering angle holding mode is switched first; when the vehicle is in stable driving conditions, the steering angle following mode is activated.

[0015] A kingpin steering fault redundancy corner module includes: a wheel, which includes a tire and a drive motor; when an electronic fault occurs in the corner module, the drive motor outputs a total drive torque compensation amount to form an equivalent steering torque at the kingpin through the longitudinal tire force of the wheel, thereby achieving steering redundancy; a steering mechanism, which includes a steering component and a steering knuckle, the steering component being connected to the wheel through the steering knuckle, the steering component driving the steering knuckle to steer, and thus driving the wheel to steer; a steering angle detection unit, which is used to collect the steering angle information of the wheel and is powered independently from the steering mechanism; and a steering controller, which is communicatively connected to the steering mechanism, the steering angle detection unit, and the drive motor, and is used for fault detection, switching between steering angle following mode and steering angle holding mode, and torque calculation of the drive motor.

[0016] Furthermore, the steering angle detection unit includes a first encoder and a second encoder; the first encoder and the second encoder are respectively arranged along the axial direction of the steering mechanism and are used to collect the steering angle information of the steering mechanism.

[0017] Furthermore, the drive motor is either a hub motor or a centralized drive motor.

[0018] A vehicle includes multiple angle modules with kingpin steering failure redundancy as described above, and a control unit;

[0019] The control unit is configured to: when no more than half of the corner modules in the vehicle experience an electronic fault, control the output of the total drive torque compensation amount of the drive motor of the faulty corner module to generate longitudinal tire force for compensating for the fault in the wheel of the faulty corner module, so as to form an equivalent steering torque around the kingpin at the kingpin, and control the faulty corner module to switch to steering angle following mode or steering angle holding mode to achieve redundant steering control of the vehicle.

[0020] Furthermore, the control unit is configured to perform the vehicle angle module steering fault redundancy control method as described in any one of claims 1 to 5.

[0021] Compared with existing technologies, inventions and creations can achieve the following beneficial effects:

[0022] In the event of kingpin steering actuator failure, steering redundancy can be achieved without the need for an additional mechanical steering actuator, thus improving system safety. It fully utilizes existing drive motors to achieve steering redundancy control, resulting in a compact structure, low cost, and ease of engineering implementation. The control mode switching is smooth, and the vehicle still maintains good controllability and stability under fault conditions. It is suitable for drive-by-wire chassis, small unmanned vehicles, and distributed drive platforms, demonstrating good versatility and application prospects. Attached Figure Description

[0023] The accompanying drawings, which form part of the invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0024] Figure 1 is a schematic diagram of the corner module provided according to an embodiment of the present invention;

[0025] Figure 2 is a flowchart of a vehicle corner module steering fault redundancy control method provided according to an embodiment of the present invention.

[0026] The reference numerals in the attached drawings include: 1, wheel; 2, steering mechanism; 21, steering assembly; 22, steering knuckle; 3, steering angle detection unit. Detailed Implementation

[0027] To make the purpose, technical solution, and advantages of the invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and do not constitute a limitation on the invention.

[0028] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of the invention can be combined with each other.

[0029] In the description of an invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature specified with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of an invention, unless otherwise stated, "a plurality of" means two or more.

[0030] In the description of the invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the invention based on the specific circumstances.

[0031] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0032] As shown in Figure 1, an embodiment of the present invention provides a redundancy angle module for kingpin steering failure, including: wheel 1, steering mechanism 2, steering angle detection unit 3 and steering controller (not shown in the figure).

[0033] Wheel 1 includes a tire and a drive motor. The drive motor is used to output the total drive torque compensation amount and is configured to output the total drive torque compensation amount according to the instructions of the steering controller in the event of an electronic failure of the corner module, thereby forming an equivalent steering torque at the kingpin through the longitudinal force of wheel 1. The kingpin is the axis of rotation of wheel 1 when it is steering, and the dashed line in Figure 1 is the kingpin.

[0034] The total drive torque output of the drive motor is compensated and redundantly configured with the steering mechanism 2. When an electronic fault occurs in the steering mechanism 2, the steering control of the wheels 1 can be achieved through the drive motor.

[0035] The drive motor can be a hub motor or a centralized drive motor; both types can achieve the steering redundancy control function of this invention.

[0036] Hub motor: The torque is directly output to wheel 1, with fast response and high control precision. No additional transmission mechanism is required. It is suitable for distributed drive chassis and can independently control the torque output of each wheel 1.

[0037] Centralized drive motor: It transmits driving force through the half-shaft to the wheel 1. It has a mature structure and high reliability. It is suitable for traditional centralized drive chassis. It can achieve longitudinal force control by adjusting the half-shaft torque distribution, thereby achieving steering redundancy.

[0038] The steering mechanism 2 includes a steering assembly 21 and a steering knuckle 22. The steering assembly 21 includes a steering motor and a reducer. The output shaft of the steering motor is connected to the input end of the reducer, and the output shaft of the reducer (i.e., the output end of the steering mechanism 2) is connected to the steering knuckle 22. The steering motor drives the steering knuckle 22 to rotate through the reducer, thereby driving the wheel 1 to rotate. In this embodiment, the steering motor is a steering motor with a brake mechanism, which is used to lock the steering mechanism 2 in case of a fault.

[0039] The steering angle detection unit 3 is used to collect the steering angle information of the wheel 1 and is powered independently from the steering mechanism 2. The independent power supply is used to block the chain reaction of power supply failure, ensure the continuous collection of steering angle information under fault conditions, and avoid the dual failure of steering drive and steering angle collection.

[0040] The steering angle detection unit 3 includes a first encoder and a second encoder. The first and second encoders are respectively arranged along the axial direction of the steering mechanism 2, providing real-time feedback of the actual steering angle information of the wheel 1 for closed-loop control. The first encoder is connected to the tail end (non-output shaft end) of the steering motor, providing real-time feedback of the motor's rotation angle and speed. The second encoder is connected to the output shaft of the reducer, directly measuring the output angle of the steering mechanism 2. The second encoder can also be replaced by a steering angle sensor.

[0041] The angle module of this application uses a steering angle detection unit 3 and a steering mechanism 2 with independent power supply, which has the following advantages: it avoids the steering mechanism 2 and the steering angle sensor from failing synchronously due to a single point failure in the power supply circuit, and ensures that even if the power supply to the steering mechanism 2 is abnormal, the steering angle detection unit 3 can still continuously output steering angle data, providing a basis for redundant control of drive motor torque compensation and steering mode switching.

[0042] The independent power supply design, together with the "dual encoder (or sensor + encoder)" that works with the steering angle detection unit 3, forms a double guarantee of "acquisition redundancy", which adapts to the high reliability and compactness requirements of small drive-by-wire chassis without adding complex mechanical structures.

[0043] The steering controller is communicatively connected to the steering mechanism 2, the steering angle detection unit 3, and the drive motor, and is used for fault detection, switching between steering angle following mode and steering angle holding mode, and calculation of the torque of the drive motor.

[0044] When the steering controller detects an electronic fault such as a failed steering motor, it immediately calculates the required compensation torque (i.e., the total drive torque compensation amount) based on the real-time steering angle information provided by the steering angle detection unit 3, and drives the drive motor of the corresponding angle module to output the total drive torque compensation amount. The total drive torque compensation amount is converted into a longitudinal force through tire-ground contact, and this longitudinal force forms a compensating steering torque around the kingpin. At the same time, the steering controller controls the angle module to switch to steering angle following mode or steering angle holding mode according to a preset safety strategy. This achieves modular redundancy steering control that does not rely on a failed steering motor.

[0045] As shown in Figure 2, an embodiment of the present invention provides a vehicle corner module steering fault redundancy control method, which includes the following steps:

[0046] S1: Acquire vehicle driving status information; driving status information includes: steering motor communication status, steering motor power supply status, actual steering angle feedback value of the angle module, and target steering angle command of the angle module. The actual steering angle feedback value of the angle module is provided by the first encoder and / or the second encoder (steering angle sensor).

[0047] S2: Based on driving status information, determine whether there is an electronic fault in the corner module.

[0048] Fault diagnosis is based on driving status information. By judging whether the steering mechanism 2 is malfunctioning (such as whether the steering motor communication exists, whether the steering motor power supply is normal, whether the actual steering angle feedback value of the angle module can follow the target steering angle command, whether the steering motor current is short-circuited or open-circuited, or whether the steering motor is overheated, etc.), it is determined whether there is an electronic fault in the angle module. Among them, steering motor communication interruption, abnormal power supply, and failure of the actual steering angle to follow the target steering angle are all judged as steering motor failure.

[0049] In this embodiment, the fault points include the first encoder, the second encoder (steering angle sensor), and the steering motor. Based on the fault combination, different failure modes are identified, and corresponding redundant control and safety strategies are activated. The specific mode definitions are as follows:

[0050] Normal operating conditions: First encoder is normal, second encoder is normal, steering motor is normal, dual encoders are working, steering motor is working normally, no redundant triggering, normal steering, steering motor does not trigger the brake mechanism.

[0051] Failure Mode 1: One of the first encoder, the second encoder (or the steering angle sensor), fails, while the other is normal, and the steering motor is normal. The normal encoder maintains normal operating status, the steering motor drives normally, the redundancy layer operates normally, and the steering motor does not trigger the brake mechanism.

[0052] Failure Mode 2: Both the first encoder and the second encoder (or steering angle sensor) fail. The steering motor drives normally, but there is no effective steering angle feedback. This triggers the steering motor's brake mechanism and executes speed limiting.

[0053] Failure Mode 3: First encoder normal, second encoder normal, steering motor failure, dual encoder feedback of steering angle, no active steering force. If the number of faulty angle modules in the vehicle is two or less, steering mechanism 2 will not trigger the brake mechanism, and will enter steering angle following mode or steering angle holding mode to maintain the basic steering function of the vehicle, or to put the vehicle into a deceleration safety stop mode. When the drive motor of the faulty angle module cannot make the actual steering angle follow the target steering angle at its maximum output capacity (such as a single angle module being completely stuck) or when there are extreme situations such as three or more angle module steering motor failures, the steering motor brake mechanism will be triggered (in this case, steering angle holding mode) to ensure the static safety of the vehicle.

[0054] Failure Mode 4: One of the first and second encoders fails, while the other is functioning normally. The steering motor fails, and the functioning encoder (either the first or second encoder) provides feedback on the steering angle, resulting in no active steering force. If the number of faulty angle modules in the vehicle is two or less, steering mechanism 2 will not trigger the brake mechanism and will enter steering angle following mode or steering angle holding mode to maintain the basic steering function of the vehicle or to put the vehicle into a deceleration safety stop mode. When the drive motor of the faulty angle module is unable to make the actual steering angle follow the target steering angle at its maximum output capacity (e.g., a single module is completely stuck) or in extreme cases such as three or more angle module steering motor failures, the steering motor brake mechanism will be triggered (in this case, steering angle holding mode) to ensure the static safety of the vehicle.

[0055] Failure Mode 5: If the steering angle module suffers an irreversible mechanical failure (such as kingpin jamming or steering motor burnout), or if both the first and second encoders fail and the steering motor fails, the front and rear wheels of the vehicle can trigger the brake mechanism (in this case, the steering angle holding mode) to lock the steering system to prevent loss of control.

[0056] It should be noted that in this embodiment, the vehicle is a four-wheeled vehicle including four corner modules.

[0057] S3: According to step S2, when an electronic fault is detected in the corner module, the steering angle deviation of wheel 1 of the faulty corner module is determined based on the driving status information.

[0058] When an electronic fault is detected in the corner module, the fault type is steering motor failure (mainly failure mode 3 and failure mode 4), and the number of faulty corner modules in the vehicle is two or less, the steering angle deviation of wheel 1 of the faulty corner module is determined based on the driving status information.

[0059] ;

[0060] in, This indicates the steering angle deviation of wheel 1 in the fault angle module. Indicates the target steering angle command. This represents the actual steering angle feedback value.

[0061] In steering angle hold mode, the target steering angle command is the fixed steering angle at the time of the fault. In steering angle follow mode, the target steering angle command is a dynamically updated target steering angle.

[0062] S4: Based on the steering angle deviation, generate the feedforward drive torque compensation amount and the feedback drive torque compensation amount of the drive motor of wheel 1, and then obtain the total drive torque compensation amount of the drive motor.

[0063] Specifically, based on steering angle deviation An algorithm combining feedforward and feedback control is used to generate the total drive torque compensation for the drive motor for redundancy control. .

[0064] Feedforward of the rate of change of rotation:

[0065] ;

[0066] ;

[0067] in, The desired rate of change of the angle is represented by t; the time of change is represented by t. K1 represents the control variable of the feedforward speed change element; K1 represents the feedforward proportional coefficient. In steering angle holding mode, = ,but =0, =0.

[0068] When the steering module is in a steady-state steering condition, the self-aligning torque, tire lateral force, and longitudinal force generated by the kingpin inclination angle and caster angle are... The torques generated around the kingpin are balanced. To counteract the inherent resistance torque in this balanced state, a steady-state feedforward control quantity based on bench calibration needs to be introduced, which is calculated as follows:

[0069] ;in, K1 represents the calculated steady-state feedforward torque; K2 represents the steady-state feedforward coefficient.

[0070] During bench calibration, adjust the value of K2 until the specified target steering angle command can be maintained under open-loop control.

[0071] The steady-state feedforward torque needs to be calculated and output in both steering angle holding mode and steering angle following mode to provide the basic balancing force to overcome the static friction and geometric self-aligning torque of the system.

[0072] Feedback control (dual closed-loop PID): used to accurately compensate for control deviations and ensure steering angle control accuracy. It adopts a "steering angle loop (outer layer) + force loop (inner layer)" structure.

[0073] Calculate the expected tire longitudinal force based on the steering angle deviation:

[0074] ;

[0075] ;

[0076] ;

[0077] ;

[0078] in, This represents the expected longitudinal force of the tire. This indicates the longitudinal force proportional term. Represents the longitudinal force integral term. K3 represents the longitudinal force differential term; K4 represents the corner ring proportional coefficient; K5 represents the corner ring integral coefficient; and K5 represents the corner ring differential coefficient.

[0079] Based on the desired tire longitudinal force The deviation from the actual longitudinal force (which can be estimated using information such as tire models or wheel speed). Calculate the feedback torque .

[0080] ;

[0081] ;

[0082] ;

[0083] ;

[0084] To prevent wheel 1 from slipping and failing to provide sufficient longitudinal force to generate a restoring torque, thus preventing wheel 1 from straightening and causing the steering angle error to accumulate and exacerbate the slippage, thus creating a vicious cycle, a coefficient for the slip ratio λ is introduced. The feedback torque is dynamically limited to prevent control failure due to wheel slippage.

[0085] ;

[0086] ;

[0087] ;

[0088] in, Indicates the torque ratio term. Represents the integral term of torque. K6 represents the torque differential term; K7 represents the force ring proportional coefficient; K8 represents the force ring integral coefficient; and K8 represents the force ring differential coefficient. This indicates the proportional term of torque after slippage. K9 represents the total drive torque compensation of the drive motor, K9 represents the dynamic adjustment coefficient to prevent excessive torque from causing wheel slippage, miu represents road surface adhesion, and Fz represents the tire vertical load.

[0089] S5: Control the output torque of the drive motor according to the total drive torque compensation amount, so that the wheel 1 of the fault angle module generates longitudinal tire force and forms an equivalent steering torque around the kingpin at the kingpin of the angle module; at the same time, control the fault angle module to switch to steering angle following mode or steering angle holding mode to achieve steering redundancy control.

[0090] In steering angle holding mode, by controlling the output torque of the drive motor, the longitudinal tire force forms an equivalent steering torque at the kingpin to keep the current steering angle unchanged.

[0091] In steering angle following mode, the magnitude and direction of the drive motor output torque are adjusted according to the deviation between the target steering angle and the actual steering angle, so that the longitudinal tire force forms the target steering torque at the kingpin, thereby realizing steering angle change control.

[0092] Preferably, in step S5, when an irreversible fault is detected in the steering mechanism 2, or a steering motor fault is detected in three or more corner modules, or the drive motor is unable to make the actual steering angle follow the target steering angle at its maximum output capacity, the brake mechanism of the steering mechanism 2 is triggered to lock the steering mechanism 2.

[0093] Preferably, when a failure of the steering mechanism 2 is detected, the steering angle holding mode is switched first; when the vehicle is in a stable driving condition, the steering angle following mode is activated.

[0094] Specifically, the total drive torque compensation output by the drive motor and the longitudinal force of the tire satisfy the following relationship:

[0095] ;but ;

[0096] in: This indicates the longitudinal force of the tire; This indicates the total drive torque compensation amount output by the drive motor; Indicates the effective radius of the tire; represents the moment of inertia of the tire; w represents the derivative of the angular velocity. 'a' represents the vertical load on the tire; 'a' represents the horizontal distance from the dynamic vertical load to the center of wheel 1.

[0097] The longitudinal force of the tire forms a steering torque around the kingpin at the tire contact point, and its magnitude is equal to the product of the longitudinal force and the lever arm distance between the tire contact point and the kingpin axis.

[0098] ;

[0099] in, It is the steering torque around the kingpin, and L is the vertical distance from the tire contact point to the extension of the kingpin.

[0100] By properly controlling the magnitude and direction of the output torque of the drive motor, the steering torque can meet the target steering control requirements, thereby achieving vehicle steering control and preventing vehicle yaw and loss of control in the event of failure of the kingpin steering actuator.

[0101] Steering angle holding mode and steering angle following mode are two mutually exclusive core modes of the software redundancy control layer. Only one mode can be executed at any given time for the same wheel 1. The mode selection is based on a dynamic decision made according to the real-time vehicle status (vehicle speed, yaw rate) and the severity of the fault. The core principle is that "if the number of faulty angle modules is two or less, the steering mechanism 2 will not trigger the mechanical brake and will enter either steering angle following mode or steering angle holding mode to maintain the basic steering function of the vehicle or to put the vehicle into a deceleration safety stop mode. When the longitudinal force provided by the drive motor of the faulty angle module cannot meet the minimum steering requirements (such as a single module being completely stuck) or in extreme cases such as three or more angle module steering motor failures, the steering motor brake mechanism is triggered (in which case the steering angle holding mode is activated) to ensure the static safety of the vehicle." The specific execution logic is as follows:

[0102] When steering mechanism 2 malfunctions and corresponds to failure modes 3 and 4 (steering motor failure), and the number of faulty angle modules in the vehicle is two or less, the vehicle selects either steering angle holding mode or steering angle following mode based on the vehicle's driving state. Steering redundancy is achieved through drive motor torque compensation. This design avoids the risk of wheel 1 locking due to direct braking of the steering motor, which could easily lead to skidding and loss of control during vehicle operation. The dynamic redundancy mode allows the vehicle to remain controllable, ensuring safe deceleration and stopping. Details are as follows:

[0103] Steering Angle Holding Mode: Using the steering angle at the moment of failure as a fixed target, the drive motor is controlled to generate an equivalent steering torque to resist changes in the steering angle and maintain the current steering angle unchanged. This mode is activated first when the vehicle detects a sudden failure of the steering motor, and is especially suitable for high-risk scenarios such as high speeds (e.g., vehicle speed > 60 km / h). It can quickly stabilize the vehicle's driving posture and prevent the vehicle from veering due to sudden changes in the front wheel steering angle.

[0104] Steering Angle Following Mode: This mode takes a dynamic target steering angle as input and adjusts the magnitude and direction of the drive motor's output torque based on the deviation between the target and actual steering angles. This causes the longitudinal tire force to generate the target steering torque at the kingpin, thereby achieving steering angle variation control. This mode is activated when the vehicle has stable driving conditions and is suitable for low-speed (e.g., vehicle speed ≤ 30 km / h) and parking scenarios to restore the vehicle's basic steering function, facilitating obstacle avoidance and parking.

[0105] For failure mode 1 (only one encoder fails): the steering motor is normal, the system degrades to use the remaining encoder, the above torque compensation algorithm based on the drive motor is not activated, and the vehicle maintains basic steering function.

[0106] For failure modes 2 and 5: due to lack of necessary feedback or complete loss of power, the above-mentioned software redundancy control is not executed, and the brake mechanism is triggered.

[0107] Steering motor brake trigger judgment logic

[0108] The steering motor brake mechanism is triggered when the longitudinal force provided by the drive motor of the faulty corner module cannot meet the minimum steering requirements (such as when a single corner module is completely stuck) or when there are extreme situations such as steering motor failures of three or more corner modules. Steering mechanism 2 triggers the brake mechanism without waiting for the steering angle deviation threshold judgment or distinguishing the fault level. The rear wheels immediately trigger the brake lock and simultaneously select the angle holding mode (the two are executed synchronously, and the mode and the brake are not mutually exclusive). This is the highest priority triggering logic, which takes precedence over all other judgment conditions. The brake lock state continues until the vehicle comes to a complete stop. After stopping, it is automatically released and switched to the following mode.

[0109] In the event of a non-steering motor failure (such as failure mode 2: both encoders fail, but the steering motor is normal), or an irreversible mechanical failure is detected in the steering mechanism 2 (such as mechanical jamming, motor burnout, etc. leading to complete loss of steering function), or the failure mode corresponding to failure mode 5 (both encoders fail, and the steering motor fails), the front and rear wheels of the vehicle will trigger the brake mechanism to lock the steering mechanism 2 to prevent the risk of loss of control.

[0110] A vehicle includes multiple angle modules as described above for implementing redundancy in kingpin steering failure, and a control unit;

[0111] The control unit is configured to: when no more than half of the corner modules in the vehicle experience an electronic failure, control the output of the total drive torque compensation amount of the drive motor of the faulty corner module to generate longitudinal tire force on the wheel 1 of the faulty corner module to compensate for the failure, so as to form an equivalent steering torque around the kingpin at the kingpin, and control the faulty corner module to switch to steering angle following mode or steering angle holding mode; thereby achieving redundant steering control of the vehicle without the need for the steering motor of the faulty corner module to participate.

[0112] The control unit is configured to execute the aforementioned vehicle angle module steering fault redundancy control method.

[0113] In summary, the vehicle corner module steering fault redundancy control method, corner module, and vehicle of the present invention have the following advantages:

[0114] In the event of steering mechanism 2 failure, steering redundancy can be achieved without adding an extra mechanical steering actuator, effectively improving system safety. Redundancy control is achieved by fully utilizing existing drive motors, resulting in a compact structure, controllable cost, and ease of engineering implementation. Smooth control mode switching ensures the vehicle maintains good controllability and stability even under fault conditions. It is applicable to drive-by-wire chassis, small unmanned vehicles, and distributed drive platforms, demonstrating strong versatility and broad application prospects.

[0115] This invention forms a tight and seamless "perception-decision-control" technology chain, from vehicle state perception, multi-dimensional fault diagnosis, and refined failure mode classification, to steering angle deviation calculation, feedforward-feedback composite torque compensation algorithm generation, and multi-strategy collaborative execution and safety control, achieving full-process coverage from fault identification to safety response. The core redundant control principle of "generating equivalent steering torque at the kingpin using the longitudinal force of the drive motor," combined with a dual-mode strategy of "holding mode" and "following mode" specifically designed for steering redundancy, and a dual-closed-loop feedforward-feedback compensation algorithm incorporating slip ratio anti-slip processing, provides a new technical path to solve the single-point failure safety problem of traditional steer-by-wire systems. Simultaneously, it sets clear safety baseline strategies for extreme scenarios such as complete encoder failure, further enhancing system reliability.

[0116] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A method for redundant control of steering faults in a vehicle corner module, characterized in that, The process includes the following steps: S1: Obtain vehicle driving status information; S2: Based on the driving status information, determine whether there is an electronic fault in the corner module; S3: According to step S2, when an electronic fault is detected in the corner module, determine the steering angle deviation of the wheel of the faulty corner module based on the driving status information. S4: Based on the steering angle deviation, generate the feedforward drive torque compensation amount and the feedback drive torque compensation amount of the drive motor of the wheel, and then obtain the total drive torque compensation amount of the drive motor. S5: Control the output torque of the drive motor according to the total drive torque compensation amount, so that the wheel of the fault angle module generates longitudinal tire force and forms an equivalent steering torque around the kingpin at the kingpin of the angle module; at the same time, control the fault angle module to switch to steering angle following mode or steering angle holding mode to achieve steering redundancy control.

2. The vehicle corner module steering fault redundancy control method according to claim 1, characterized in that, The driving status information includes: the communication status of the steering mechanism of the angle module, the power supply status of the steering mechanism, the actual steering angle feedback value of the angle module, and the target steering angle command of the angle module.

3. The vehicle corner module steering fault redundancy control method according to claim 1, characterized in that, In step S5, in the steering angle holding mode, the output torque of the drive motor is controlled to make the longitudinal tire force form an equivalent steering torque at the kingpin so as to keep the current steering angle unchanged. In steering angle following mode, the magnitude and direction of the drive motor output torque are adjusted according to the deviation between the target steering angle and the actual steering angle, so that the longitudinal tire force forms the target steering torque at the kingpin, thereby realizing steering angle change control.

4. The vehicle corner module steering fault redundancy control method according to claim 1, characterized in that, In step S5, the brake mechanism of the steering mechanism is triggered to lock the steering mechanism when any of the following conditions are detected: the steering mechanism suffers an irreversible mechanical failure; more than half of the steering mechanisms of all corner modules in the vehicle fail; or the drive motor is unable to make the actual steering angle follow the target steering angle at its maximum output capacity.

5. The vehicle corner module steering fault redundancy control method according to claim 1 or 3, characterized in that, When a steering mechanism failure is detected, the steering angle holding mode is switched first; when the vehicle is under stable driving conditions, the steering angle following mode is activated.

6. A corner module for redundancy in kingpin steering failure, characterized in that, include: A wheel, the wheel including a tire and a drive motor; When an electronic fault occurs in the corner module, the drive motor outputs a total drive torque compensation amount to form an equivalent steering torque at the kingpin through the longitudinal tire force of the wheel, thereby achieving steering redundancy. A steering mechanism, comprising a steering assembly and a steering knuckle, wherein the steering assembly is connected to the wheel via the steering knuckle, and the steering assembly drives the steering knuckle to turn, thereby driving the wheel to turn; A steering angle detection unit is used to collect the steering angle information of the wheels and is powered independently from the steering mechanism. The steering controller is communicatively connected to the steering mechanism, the steering angle detection unit, and the drive motor, and is used for fault detection, switching between steering angle following mode and steering angle holding mode, and calculating the torque of the drive motor.

7. The angle module for redundancy in kingpin steering failure according to claim 6, characterized in that, The steering angle detection unit includes a first encoder and a second encoder; the first encoder and the second encoder are respectively arranged along the axial direction of the steering mechanism and are used to collect the steering angle information of the steering mechanism.

8. The angle module for redundancy in kingpin steering failure according to claim 6, characterized in that, The drive motor is either a hub motor or a centralized drive motor.

9. A vehicle, characterized in that, The system includes multiple corner modules with kingpin steering fault redundancy as described in any one of claims 6 to 8, and a control unit; the control unit is configured to: when no more than half of the corner modules in the vehicle experience an electronic fault, control the drive motor of the faulty corner module to output a total drive torque compensation amount, so that the wheels of the faulty corner module generate a longitudinal tire force to compensate for the fault, thereby forming an equivalent steering torque around the kingpin at the kingpin, and control the faulty corner module to switch to a steering angle following mode or a steering angle holding mode, thereby realizing the vehicle's steering redundancy control.

10. The vehicle according to claim 9, characterized in that, The control unit is configured to perform the vehicle corner module steering fault redundancy control method as described in any one of claims 1 to 5.

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