A method for controlling stability of a split road surface vehicle, a storage medium and an electronic device

Abstract

This invention discloses a method, storage medium, and electronic device for vehicle stability control on split-road surfaces, belonging to the field of vehicle dynamics control. This scheme acquires wheel speeds, yaw rates, longitudinal accelerations, driving signals, and vehicle speeds; identifies the split-road surface and determines the high-adhesion side based on wheel and vehicle speeds; determines the ideal yaw rate based on driving signals and vehicle speeds; calculates a feedforward compensation torque based on torque balance; calculates a feedback compensation torque based on the deviation between the ideal and actual yaw rates; and then calculates a target compensation torque; determines the theoretical rear wheel steering angle based on the target compensation torque, longitudinal acceleration, wheel speed, and vehicle speed; if the theoretical steering angle exceeds a steering angle threshold, determines the remaining torque based on the difference between the two; and uses the remaining torque to adjust the rear wheel on the high-adhesion side. This invention achieves smooth compensation of yaw torque on split-road surfaces and maintains vehicle yaw stability through a two-layer synergy of rear-wheel steering priority and torque adjustment supplementation.

Description

Technical Field

[0001] This application relates to the field of vehicle chassis control technology, specifically to a method for controlling the stability of vehicles on split-road surfaces, a storage medium, and an electronic device. Background Technology

[0002] When braking or driving on split-surface surfaces (i.e., surfaces with significantly different coefficients of adhesion on the left and right sides of a vehicle), current technologies generally employ a "lower selection" principle for ABS (Anti-lock Braking System) and TCS (Traction Control System) to ensure longitudinal braking / driving efficiency and yaw stability. This approach sacrifices the vehicle's longitudinal performance. The significant adhesion of the high-adhesion side is wasted, leading to increased braking distance or insufficient acceleration, posing a safety hazard. Summary of the Invention

[0003] The technical problem to be solved by this application is the poor longitudinal braking / driving performance caused by the use of low selection strategy in existing split-road vehicle control technology, and thus provides a split-road vehicle stability control method, storage medium and electronic device.

[0004] Firstly, the technical solution of this application provides a method for controlling the stability of vehicles on split-road surfaces, including: Obtain vehicle status information, including wheel speed, yaw rate, longitudinal acceleration, driving signals, and vehicle speed; The road surface is identified based on the wheel speeds and vehicle speed, and the side with high adhesion is determined; the ideal yaw rate is determined based on the driving signals and vehicle speed. The feedforward compensation torque is calculated based on the torque balance model, the feedback compensation torque is calculated based on the deviation between the ideal yaw rate and the actual yaw rate, and the target compensation torque is calculated based on the feedforward compensation torque and the feedback compensation torque. The theoretical steering angle of the rear wheels is determined based on the target compensation torque, the longitudinal acceleration, the wheel speeds of each wheel, and the vehicle speed. If the theoretical rear wheel steering angle exceeds the steering angle threshold, the remaining torque is determined based on the difference between the theoretical rear wheel steering angle and the steering angle threshold. The remaining torque is used to adjust the rear wheel on the high-adhesion side.

[0005] Some solutions describe vehicle stability control methods for split-road surfaces, where identifying the split-road surface and determining the high-adhesion side based on the wheel speeds of each wheel and the vehicle speed includes: Calculate the slip ratio of each wheel based on the wheel speed and the vehicle speed; When the difference in slip ratio between the wheels on both sides of the same axle exceeds a preset threshold, the road surface on which the vehicle is traveling is determined to be a split road surface. The high-adhesion side and low-adhesion side are determined based on the slip ratio of the wheels on both sides of the same axle.

[0006] In some solutions for vehicle stability control on split-road surfaces, the driving signal includes a steering wheel angle signal, and the step of determining the ideal yaw rate based on the driving signal and vehicle speed includes: Based on the steering wheel angle signal and the vehicle speed, the ideal yaw rate is calculated using a pre-stored two-degree-of-freedom vehicle reference model.

[0007] Some solutions describe vehicle stability control methods for split-road surfaces, including the calculation of feedforward compensation torque based on a torque balance model, which includes: Obtain the driving torque and braking torque fed back by the actuators of each wheel; Based on the driving torque, braking torque, wheel speed, preset wheel moment of inertia, and wheel radius of rotation of each wheel, calculate the longitudinal force of each wheel respectively; The feedforward compensation torque is calculated based on the longitudinal force of each wheel and the preset wheel track.

[0008] Some solutions describe vehicle stability control methods for split-plane roads, including calculating a feedback compensation torque based on the deviation between the ideal yaw rate and the actual yaw rate, and calculating a target compensation torque based on the feedforward compensation torque and the feedback compensation torque, comprising: Obtain the pre-calibrated scaling factor Integral coefficient and differential gain coefficient ; Calculate feedback compensation torque : ; in, This indicates the deviation between the ideal yaw rate and the actual yaw rate; The sum of the feedforward compensation torque and the feedback compensation torque is taken as the target compensation torque.

[0009] Some solutions describe vehicle stability control methods for split-road surfaces, including determining the theoretical rear wheel steering angle based on the target compensation torque, the longitudinal acceleration, the wheel speeds of each wheel, and the vehicle speed. The target lateral force is calculated based on the target compensation torque and the distance from the vehicle's center of gravity to the rear axle; The rear axle lateral stiffness is determined based on the longitudinal acceleration, the wheel speeds of each wheel, and the vehicle speed. The theoretical steering angle of the rear wheel is obtained by dividing the target lateral force by the rear axle lateral stiffness.

[0010] Some solutions describe vehicle stability control methods for split-road surfaces, including determining the rear axle lateral stiffness based on the longitudinal acceleration, the wheel speeds of each wheel, and the vehicle speed. Calculate the rear axle load based on the longitudinal acceleration; The average slip ratio is calculated based on the wheel speeds of each wheel and the vehicle speed. The rear axle lateral stiffness is determined by looking up the data in a pre-stored data table based on the rear axle load and the average slip ratio.

[0011] Some solutions describe vehicle stability control methods for split-road surfaces, including determining the rear axle lateral stiffness by looking up a pre-stored data table based on the rear axle load and the average slip ratio. The pre-calibrated and stored data table of lateral stiffness corresponding to rear axle load and average slip ratio is used as the pre-stored data table. Using the calculated rear axle load and average slip ratio as indexes, the corresponding rear axle lateral stiffness is retrieved from the pre-stored data table.

[0012] In some solutions for vehicle stability control on split-road surfaces, the method for determining the remaining torque based on the difference between the theoretical rear wheel steering angle and the steering angle threshold if the theoretical rear wheel steering angle exceeds a steering angle threshold further includes: The smaller of the theoretical rear wheel steering angle and the steering angle threshold is used as the final target rear wheel steering angle output.

[0013] Some solutions describe vehicle stability control methods for split-plane roads, where, if the theoretical rear wheel steering angle exceeds a steering angle threshold, the remaining torque is determined based on the difference between the theoretical rear wheel steering angle and the steering angle threshold. This includes: The residual torque is the product of the difference, the rear axle lateral stiffness, and the distance from the vehicle's center of gravity to the rear axle.

[0014] Some solutions describe vehicle stability control methods for split-plane roads, where the residual torque is used to adjust the rear wheel on the high-adhesion side, including: The remaining torque is converted into a reduction in the driving or braking torque of the rear wheel on the high-adhesion side; The torque reduction is applied to decrease the torque of the rear wheel on the high-adhesion side.

[0015] In some solutions, the vehicle stability control method for split-road surfaces includes driving signals such as accelerator pedal position signals and brake pedal position signals; after the step of converting the residual torque into a reduction in the driving or braking torque of the high-adhesion side rear wheel, it further includes: Calculate the driving force request gradient or braking force request gradient based on the vehicle speed and the accelerator pedal position signal / brake pedal position signal; The gain coefficient is determined based on the vehicle speed and the driving force request gradient or the braking force request gradient. The torque reduction is corrected based on the gain coefficient.

[0016] Secondly, the present application provides a computer-readable storage medium storing program information, wherein a computer reads the program information and executes the steps of the vehicle stability control method for split-road surfaces as described in any one of the technical solutions of the first aspect.

[0017] Thirdly, the present application provides a computer program product, including a computer program / instruction, which, when executed by a processor, implements the steps of the split-road vehicle stability control method described in any one of the technical solutions of the first aspect.

[0018] Fourthly, the present application provides an electronic device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the split-road vehicle stability control method described in any one of the first aspects.

[0019] Fifthly, the present application provides a vehicle that includes the computer-readable storage medium described in the second aspect, the computer program product described in the third aspect, or the electronic device described in the fourth aspect.

[0020] The technical solution provided in this application has the following technical effects compared with the prior art: The vehicle stability control method, storage medium, and electronic equipment provided in this application acquire vehicle state information such as wheel speeds, yaw rates, longitudinal accelerations, driving signals, and vehicle speed. Based on wheel speeds and vehicle speed, it identifies the split road surface and determines the high-adhesion side, accurately determining whether the vehicle is in a split road surface condition with inconsistent left and right adhesion coefficients and identifying the high-adhesion side as the target side. Furthermore, it determines the ideal yaw rate based on driving signals and vehicle speed, calculates the feedforward compensation torque using a torque balance model, and calculates the feedback compensation torque based on the deviation between the ideal and actual yaw rates. Finally, it calculates the target compensation torque using both the feedforward and feedback compensation torques. This approach allows for rapid compensation of yaw torque disturbances caused by the split road surface through the feedforward stage and correction of residual deviations through the feedback stage, thereby improving steady-state control accuracy while ensuring response speed. Based on the target compensation torque, longitudinal acceleration, wheel speeds, and vehicle speed, the theoretical rear wheel steering angle is determined. Active rear wheel steering is prioritized to compensate for yaw moment, maximizing vehicle driving and braking performance under low-adhesion conditions such as split-plane roads. When the theoretical rear wheel steering angle exceeds a threshold, the remaining torque is determined based on the difference between the theoretical angle and the threshold. This remaining torque is then used to adjust the rear wheel on the high-adhesion side, reducing its driving or braking torque to weaken the yaw effect and supplement the compensation torque required by the rear wheel steering. Therefore, this application's solution, through a synergistic strategy of prioritizing rear wheel steering and supplementing with driving and braking torque adjustment, achieves excellent braking performance while maintaining good yaw stability during driving or braking on split-plane roads. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall architecture of the vehicle control system; Figure 2 This is a flowchart of a vehicle stability control method for split-road surfaces according to one embodiment of this application; Figure 3 This is a flowchart illustrating the steps of identifying split road surfaces and determining the high-adhesion side according to one embodiment of this application; Figure 4 This is a flowchart illustrating the steps for calculating the feedforward compensation torque according to one embodiment of this application; Figure 5 This is a flowchart illustrating the basic principle of calculating the compensated yaw moment according to one embodiment of this application; Figure 6 This is a flowchart illustrating the steps for calculating the theoretical rear wheel steering angle according to one embodiment of this application; Figure 7 This is a flowchart illustrating the adjustment of the rear wheel on the high-adhesion side using the residual torque according to one embodiment of this application; Figure 8This is a schematic diagram of the hardware connections of an electronic device that performs a vehicle stability control method on a split-road surface according to an embodiment of this application. Detailed Implementation

[0022] The specific embodiments of this application will be further described below with reference to the accompanying drawings.

[0023] It is readily understood that, based on the technical solution of this application, various structural and implementation methods can be interchanged by those skilled in the art without altering the essential spirit of this application. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solution of this application and should not be considered as the entirety of this application or as limitations or restrictions on the technical solution of the application.

[0024] The vehicle stability control method for split-road surfaces provided in this application is applied to, for example, Figure 1 The vehicle chassis integrated control system shown below. Figure 1 This application describes the system configuration and the signal relationships between its components. (Refer to...) Figure 1 The system mainly includes a sensor group, a controller, an active rear-wheel steering actuator, and a four-wheel drive braking actuator.

[0025] The sensor array is used to collect vehicle status signals in real time and transmit them to the controller. Specifically, it includes: The steering wheel angle sensor is used to collect the driver's steering wheel angle signal and transmit the signal to the controller; An inertial measurement unit (IMU) is used to acquire the vehicle's yaw rate and longitudinal acceleration signals and transmit these signals to the controller. Brake pedal position sensor is used to collect the driver's brake pedal position signal and transmit the signal to the controller; The drive pedal position sensor is used to collect the driver's drive pedal position signal and transmit the signal to the controller; The left front wheel speed sensor, right front wheel speed sensor, left rear wheel speed sensor, and right rear wheel speed sensor are respectively installed at the four wheels to collect the wheel speed signal of each wheel and transmit the signal to the controller.

[0026] All the signals collected by the aforementioned sensors together constitute the vehicle status signal, which serves as the input to the controller.

[0027] The controller is connected to the sensor array, the active rear-wheel steering actuator, and the four-wheel drive brake actuator. The controller receives vehicle status signals from the sensor array, and simultaneously receives braking and driving feedback signals (i.e., actual driving and braking torques) from the four-wheel drive brake actuator. Internally, it runs the rule-based control algorithm proposed in this application, and after calculation, outputs target braking and driving signals to the four-wheel drive brake actuator, and a target steering angle signal to the active rear-wheel steering actuator. The controller can be an independent control unit or a functional module integrated into the vehicle chassis domain controller.

[0028] The four-wheel drive brake actuators are respectively installed on the left front wheel, right front wheel, left rear wheel, and right rear wheel. Each wheel has an independent drive actuator and brake actuator to receive target drive signals and target braking signals from the controller, and to perform corresponding drive torque and braking torque adjustments. The drive actuator is used to achieve independent drive torque adjustment for each wheel, and its implementation includes, but is not limited to, wheel-side motors or wheel hub motors. The brake actuator is used to achieve independent braking torque adjustment for each wheel, and its implementation includes, but is not limited to, ESP hydraulic units, electromechanical brakes (EMB), or motor kinetic energy recovery brake controllers. While executing controller commands, each actuator simultaneously feeds back the current actual braking feedback signal and drive feedback signal (i.e., actual drive torque and braking torque) to the controller in real time.

[0029] The active rear wheel steering actuator is connected to the controller signal to receive the target steering angle signal output by the controller and perform the corresponding rear wheel steering action.

[0030] Based on the above system, this embodiment provides a vehicle stability control method for split-road surfaces, applied to... Figure 1 In the controller shown, such as Figure 2 As shown, the method includes: S100: Obtain vehicle status information, including wheel speed, yaw rate, longitudinal acceleration, driving signal, and vehicle speed.

[0031] In this step, the controller acquires vehicle status information, including wheel speeds, yaw rate, longitudinal acceleration, driving signals, and vehicle speed. Specifically, wheel speeds are acquired in real-time by four wheel speed sensors located on the left front wheel, right front left rear wheel, and right rear wheel; yaw rate and longitudinal acceleration are acquired in real-time by an inertial measurement unit (IMU); driving signals include steering wheel angle signals, brake pedal position signals, and drive pedal position signals, acquired in real-time by steering wheel angle sensors, brake pedal position sensors, and drive pedal position sensors, respectively; vehicle speed is calculated by the controller based on a combination of wheel speeds and longitudinal acceleration. Each sensor transmits the acquired signals to the controller in real-time as input for subsequent control calculations.

[0032] S200: Identify the opposing road surface and determine the high-adhesion side based on the wheel speeds of each wheel and the vehicle speed; determine the ideal yaw rate based on the driving signals and vehicle speed.

[0033] In this step, the controller identifies whether the vehicle is currently in a split-road condition based on the wheel speeds and vehicle speed obtained in S100. If the identification result is yes, the controller further determines the high-adhesion side of the split-road surface to clarify the target object for subsequent torque adjustment. At the same time, the controller determines the ideal yaw rate that the vehicle should achieve under the current driving input based on the driving signal and vehicle speed, providing a target benchmark for the calculation of subsequent feedback compensation torque.

[0034] S300: Calculate the feedforward compensation torque based on the torque balance model, calculate the feedback compensation torque based on the deviation between the ideal yaw rate and the actual yaw rate, and calculate the target compensation torque based on the feedforward compensation torque and the feedback compensation torque.

[0035] In this step, the controller calculates the feedforward compensation torque based on the torque balance model. This torque balance model is a physical model pre-stored in the controller for calculating the feedforward compensation torque, based on the yaw moment balance principle in vehicle dynamics. This feedforward compensation torque is used to quickly compensate for yaw moment disturbances caused by differences in driving or braking forces on the left and right sides of the split road surface. Simultaneously, the controller reads the actual yaw rate collected by the IMU, calculates the deviation between the ideal yaw rate determined in S200 and the actual yaw rate, and calculates the feedback compensation torque based on this deviation according to feedback control logic. This feedback compensation torque is used to correct any residual yaw rate deviation that may exist after feedforward compensation. Finally, the controller superimposes the feedforward compensation torque and the feedback compensation torque to obtain the target compensation torque.

[0036] S400: Determine the theoretical steering angle of the rear wheels based on the target compensation torque, the longitudinal acceleration, the wheel speeds of each wheel, and the vehicle speed.

[0037] In this step, the controller determines the rear wheel lateral force required to achieve the target compensation torque based on the target compensation torque calculated in S300. Simultaneously, the controller estimates the current rear axle load based on the longitudinal acceleration obtained in S100 and calculates the average slip ratio based on the wheel speeds and vehicle speed. Based on this, the controller determines the current rear axle lateral stiffness from a pre-stored data table using the estimated rear axle load and average slip ratio, and then determines the theoretical rear wheel steering angle based on the required rear wheel lateral force and this lateral stiffness. This theoretical steering angle characterizes the rear wheel steering angle required to generate the target compensation torque.

[0038] S500: If the theoretical rear wheel angle exceeds the angle threshold, the remaining torque is determined based on the difference between the theoretical rear wheel angle and the angle threshold.

[0039] In this step, the controller obtains the steering angle threshold (i.e., the maximum allowable steering angle of the rear axle) determined based on the current vehicle speed. The controller compares the theoretical rear wheel steering angle calculated in S400 with this steering angle threshold. If the theoretical rear wheel steering angle does not exceed the steering angle threshold, it indicates that the active rear wheel steering system can independently achieve the entire target compensation torque without additional adjustment; if the theoretical rear wheel steering angle exceeds the steering angle threshold, it indicates that the adjustment capability of the active rear wheel steering system has reached saturation and cannot fully achieve the target compensation torque. In this case, the controller determines the portion of the compensation torque that the active rear wheel steering failed to achieve, i.e., the remaining torque, based on the difference between the theoretical rear wheel steering angle and the steering angle threshold.

[0040] S600: Adjust the rear wheel on the high-adhesion side using the remaining torque.

[0041] In this step, the controller converts the residual torque determined in S500 into an adjustment to the driving or braking torque of the high-adhesion rear wheel. Specifically, by reducing the driving torque output from the high-adhesion rear wheel (driving condition) or reducing the braking torque output from the high-adhesion rear wheel (braking condition), the excessive longitudinal force generated by the high-adhesion wheel due to the high road surface adhesion is weakened, thereby reducing the yaw effect of that wheel on the vehicle. Since this reduction is applied to the high-adhesion rear wheel, it effectively compensates for the remaining torque demand after the active rear wheel steering capability saturates, and maximizes the maintenance of the vehicle's longitudinal dynamics and braking performance under extreme conditions on split-road surfaces, ensuring the vehicle maintains a stable driving posture.

[0042] The solution provided in this embodiment acquires vehicle state information such as wheel speeds, yaw rates, longitudinal acceleration, driving signals, and vehicle speed. Based on wheel speeds and vehicle speed, it identifies the split-road surface and determines the high-adhesion side. This accurately determines whether the vehicle is in a split-road surface condition with inconsistent left and right adhesion coefficients and identifies the high-adhesion side as the target side. Furthermore, it determines the ideal yaw rate based on driving signals and vehicle speed, calculates the feedforward compensation torque using a torque balance model, and calculates the feedback compensation torque based on the deviation between the ideal and actual yaw rates. Finally, it calculates the target compensation torque using the feedforward and feedback compensation torques. This allows for rapid compensation of yaw torque disturbances caused by the split-road surface through the feedforward stage and correction of residual deviations through the feedback stage, thereby improving steady-state control accuracy while maintaining response speed. The theoretical rear wheel steering angle is determined based on the target compensation torque, longitudinal acceleration, wheel speeds, and vehicle speed. Active rear-wheel steering is prioritized for yaw torque compensation, maximizing the vehicle's driving or braking performance in low-adhesion conditions like split-road surfaces. When the theoretical rear wheel steering angle exceeds the steering angle threshold, the remaining torque is determined based on the difference between the theoretical rear wheel steering angle and the steering angle threshold. This remaining torque is then used to adjust the rear wheel on the high-adhesion side, reducing the driving or braking torque of the wheel on the high-adhesion side to weaken its yaw effect on the vehicle, thus compensating for the insufficient compensation torque required by the rear wheel steering. Therefore, this application's solution, through a synergistic strategy of prioritizing rear wheel steering and supplementing with driving and braking torque adjustment, achieves excellent braking performance while maintaining good yaw stability during driving or braking on split-road surfaces.

[0043] Preferably, the vehicle stability control method for split-road surfaces provided in this application, such as... Figure 3 As shown, step S200, which involves identifying the split road surface and determining the high-adhesion side based on the wheel speeds of each wheel and the vehicle speed, includes: S201: Calculate the slip ratio of each wheel based on the wheel speed and the vehicle speed.

[0044] In this step, the controller receives real-time wheel speed signals from four wheel speed sensors, as well as the vehicle speed signal calculated from the combined wheel speed and longitudinal acceleration. For each wheel, the controller calculates its current slip ratio based on its wheel speed and the vehicle speed. The slip ratio characterizes the degree of slippage of a wheel relative to its pure rolling state during driving or braking. The slip ratio of each wheel is calculated independently to obtain its individual slip ratio, allowing for comparison of the slip ratios on the left and right sides of the same axle. The formula for calculating the slip ratio in this step is common knowledge in the field and is expressed as: ;in, For vehicle speed, This refers to the wheel speed.

[0045] S202: When the difference in slip ratio between the wheels on both sides of the same axle exceeds a preset threshold, the road surface on which the vehicle is traveling is determined to be a split road surface.

[0046] On a split-type road surface, the wheels on the left and right sides of the same axle are on surfaces with drastically different coefficients of adhesion. The wheel on the side with lower adhesion will slip or tend to lock up due to insufficient traction, resulting in a significantly increased slip ratio. In contrast, the wheel on the side with higher adhesion will maintain normal rolling, with its slip ratio remaining at a lower level. The significant difference in slip ratio between the two sides is the core criterion for judgment. This preset threshold is usually determined through calibration tests to exclude minor differences in slip ratio caused by factors such as load transfer and slight road surface unevenness under normal driving conditions, thus avoiding false triggering.

[0047] In this step, the controller compares the slip ratios of the left front wheel and the right front wheel, and calculates the difference between their slip ratios; simultaneously, it compares the slip ratios of the left rear wheel and the right rear wheel, and calculates the difference between their slip ratios. For any axle, when the difference in slip ratio between its left and right wheels exceeds a pre-calibrated threshold stored in the controller, the controller determines that the road surface the vehicle is currently traveling on is a split road surface.

[0048] S203: Determine the high-adhesion side and low-adhesion side based on the slip ratio of the wheels on both sides of the same axle.

[0049] In this step, after determining that the vehicle is on a split-road surface, the controller further determines which side is the high-adhesion side and which side is the low-adhesion side based on the relative magnitude of the slip ratio. Under driving conditions, the low-adhesion side wheel slips due to insufficient traction, its wheel speed is higher than the actual vehicle speed, and its slip ratio is positive and relatively large; the high-adhesion side wheel has sufficient traction, and its slip ratio is small or close to zero. Therefore, on the same axle, the side with the larger slip ratio is the low-adhesion side, and the side with the smaller slip ratio is the high-adhesion side. Under braking conditions, the low-adhesion side wheel tends to lock up due to insufficient traction, its wheel speed decreases faster than the vehicle speed decreases, and its slip ratio is negative and relatively large; the high-adhesion side wheel can decelerate normally. Similarly, on the same axle, the side with the larger absolute value of the slip ratio is the low-adhesion side, and the side with the smaller absolute value of the slip ratio is the high-adhesion side. In this step, the controller completes the identification of the split-road surface and the distinction between the high-adhesion and low-adhesion sides, providing a clear target for subsequent steps to adjust the high-adhesion rear wheel using residual torque.

[0050] Further, the driving signal includes a steering wheel angle signal. Step S200, determining the ideal yaw rate based on the driving signal and vehicle speed, includes: calculating the ideal yaw rate using a pre-stored two-degree-of-freedom vehicle reference model based on the steering wheel angle signal and the vehicle speed. In this step, the controller receives the steering wheel angle signal collected and transmitted in real time by the steering wheel angle sensor. This signal reflects the driver's current steering intention, i.e., the steering angle the driver wants the vehicle to turn. The controller uses the acquired steering wheel angle signal and current vehicle speed as inputs, calls the pre-stored two-degree-of-freedom vehicle reference model in the controller, and calculates the ideal yaw rate the vehicle should achieve under the current driver steering input. The two-degree-of-freedom vehicle reference model is a linear model established based on vehicle dynamics principles; its "two degrees of freedom" refers to the vehicle considering only lateral and yaw motion in the horizontal plane. This model simplifies the vehicle as a rigid body with lateral velocity and yaw rate, using the front wheel angle (calculated from the steering wheel angle and steering system transmission ratio) and vehicle speed as inputs, and the ideal yaw rate as the output. The mathematical expression for the two-degree-of-freedom vehicle reference model can be written as: ; in, Represents the ideal yaw rate. Indicates vehicle speed. Indicates wheelbase. Indicates the overall vehicle weight. and These represent the distances from the center of mass to the front and rear axles, respectively. and These are the equivalent lateral stiffnesses of the front and rear axles, respectively. The front wheel steering angle (which can be calculated from the steering wheel angle) is a parameter. All vehicle parameters mentioned above are pre-stored in the controller. The two-degree-of-freedom vehicle reference model describes the ideal yaw rate under a given vehicle speed and front wheel steering angle input. The controller calculates the ideal yaw rate using the two-degree-of-freedom vehicle reference model, which serves as the target value for subsequent feedback control. In actual vehicle operation, this target value represents the driver's desired yaw motion state—when the actual yaw rate equals this ideal value, the vehicle travels stably according to the driver's steering intention; when there is a deviation, it indicates that the vehicle has a tendency to understeer or oversteer, or is disturbed by external disturbances such as road surface disturbances, requiring correction.

[0051] Furthermore, such as Figure 4 As shown, in step S300, the feedforward compensation torque is calculated through the following steps: S301: Obtain the driving torque and braking torque fed back by the actuators of each wheel.

[0052] Combination Figure 1As shown, the controller receives real-time feedback of the actual driving torque from each drive actuator located on the left front wheel, right front wheel, left rear wheel, and right rear wheel, as well as the real-time feedback of the actual braking torque from each brake actuator. These torque feedback signals reflect the actual driving torque and braking torque output by each wheel at the current moment.

[0053] S302: Calculate the longitudinal force of each wheel based on the driving torque, braking torque, wheel speed, preset wheel moment of inertia, and wheel radius of rotation of each wheel.

[0054] For each wheel, after the driving or braking torque is applied, a portion is used to overcome the wheel's rotational inertia (the product of moment of inertia and angular acceleration), and the remaining portion is transmitted to the vehicle body as a longitudinal force through the contact between the tire and the road surface. Therefore, in this step, the controller calculates the current longitudinal force of each wheel using its actual driving torque, actual braking torque, wheel speed, and the wheel's moment of inertia and radius of rotation pre-stored in the controller as inputs.

[0055] in, For driving torque, For braking torque, For the moment of inertia of the wheel, The angular velocity of the wheel. The radius of the wheel's rotation.

[0056] Since each wheel is calculated independently, this step can accurately reflect the difference in longitudinal force between the left and right wheels of the same axle under the condition of a split road surface: the wheel on the high-adhesion side can generate a larger longitudinal force due to sufficient adhesion, while the wheel on the low-adhesion side generates a smaller longitudinal force due to insufficient adhesion. The difference between the two is the root cause of the vehicle generating an undesirable yaw moment.

[0057] S303: The feedforward compensation torque is calculated based on the longitudinal force of each wheel and the preset wheel track.

[0058] The yaw disturbance caused by the split road surface is directly determined by the actual longitudinal force of each wheel at the current moment. Step S302 can calculate the longitudinal force. In this step, before it fully affects the vehicle's yaw motion, a compensating torque in the opposite direction can be actively applied through active rear wheel steering or drive braking adjustment to cancel it out. The controller output is a torque value, which will be preferentially converted into rear wheel angle by the active rear wheel steering actuator in subsequent steps; when the rear wheel steering capability is saturated, the remaining part of the torque will be reduced by the drive braking actuator by reducing the torque of the wheel on the high-adhesion side. Therefore, in this step, the controller subtracts the longitudinal forces of the left front wheel from the right front wheel, and subtracts the longitudinal forces of the left rear wheel from the right rear wheel, adds the differences, and multiplies them by half of the wheelbase pre-stored in the controller to obtain the actual yaw disturbance torque caused by the split road surface at the current moment. The controller outputs a feedforward compensating torque that is opposite in direction and equal in magnitude to this yaw disturbance torque. The specific formula is expressed as: ; in, Indicates the feedforward compensation torque. These are the longitudinal forces of the four wheels. This refers to the wheel track.

[0059] Further, in step S300, the step of calculating the feedback compensation torque based on the deviation between the ideal yaw rate and the actual yaw rate, and calculating the target compensation torque based on the feedforward compensation torque and the feedback compensation torque, includes: obtaining a pre-calibrated proportional coefficient. Integral coefficient and differential gain coefficient The feedback compensation torque is calculated according to the following formula. : ;in, This represents the deviation between the ideal yaw rate and the actual yaw rate; finally, the sum of the feedforward compensation torque and the feedback compensation torque is taken as the target compensation torque. ,Right now: .

[0060] In this scheme, the controller reads the pre-calibrated and stored proportional gain, integral gain, and derivative gain coefficients. The proportional gain is used to respond instantly to the deviation at the current moment; the larger the deviation, the greater the compensation torque output by the proportional term, enabling the vehicle to quickly return to center. The integral gain is used to eliminate steady-state residual deviations, continuously accumulating compensation even when the vehicle has small deviations over a long period until the deviation reaches zero. The derivative gain is used to predict the trend of deviation changes, applying a reverse force in advance before the deviation increases significantly, thus suppressing oscillations and improving system damping. These three coefficients are the control parameters of the feedback controller, and their values ​​are pre-calibrated through vehicle platform simulation and real-vehicle testing. The basic principle of calibration is to enable the feedback controller to respond quickly and accurately to yaw rate deviations while ensuring system stability, and to suppress the influence of measurement noise and external disturbances. The three calibrated coefficients are stored in the controller and are available for real-time use by the control algorithm during vehicle operation. The controller calculates the deviation between the ideal yaw rate and the actual yaw rate, which reflects the difference between the current actual yaw motion of the vehicle and the driver's desired yaw motion. Compared to feedforward compensation torque, feedback compensation torque does not directly depend on the measured value of the split-road disturbance. Instead, it indirectly determines whether there is uncompensated residual yaw torque based on the deviation between the vehicle's actual yaw response and the ideal target. Therefore, the feedforward part is responsible for quickly and directly compensating for measurable split-road disturbances, while the feedback part is responsible for correcting any residual errors that may exist after feedforward compensation and dealing with other unmodeled disturbances. The two complement each other. The controller's feedforward compensation torque and feedback compensation torque are added together, and the sum of the two is used as the final target compensation torque.

[0061] Further, determining the theoretical rear wheel steering angle based on the target compensation torque, the longitudinal acceleration, the wheel speeds of each wheel, and the vehicle speed includes: calculating the target lateral force based on the target compensation torque and the distance from the vehicle's center of gravity to the rear axle; determining the rear axle lateral stiffness based on the longitudinal acceleration, the wheel speeds of each wheel, and the vehicle speed; and obtaining the theoretical rear wheel steering angle by dividing the target lateral force by the rear axle lateral stiffness. Specifically, the controller first calculates the target lateral force based on the target compensation torque and the distance from the vehicle's center of gravity to the rear axle, according to the physical relationship between yaw moment and lateral force. Simultaneously, the controller estimates the current rear axle load based on the longitudinal acceleration, calculates the average slip ratio based on the wheel speeds of each wheel and the vehicle speed, and uses the rear axle load and average slip ratio as an index to look up the current rear axle lateral stiffness from a pre-stored data table. Finally, the controller divides the target lateral force by the rear axle lateral stiffness to obtain the theoretical rear wheel steering angle, which characterizes the rear wheel steering angle required to generate the target lateral force.

[0062] Preferably, such as Figure 6 As shown, the theoretical rear wheel steering angle in S400 is obtained through the following steps: S401: Calculate the target lateral force based on the target compensation torque and the distance from the vehicle's center of gravity to the rear axle: ; This is the distance from the vehicle's center of gravity to the rear axle. The target lateral force represents the magnitude of the lateral force that the rear axle tires need to exert on the road surface to generate the target compensating torque, and is an intermediate variable for subsequent calculations of the theoretical rear wheel steering angle.

[0063] S402: Calculate the rear axle load based on the longitudinal acceleration.

[0064] During vehicle acceleration or braking, the load on the front and rear axles dynamically transfers due to inertial forces: during acceleration, the load shifts rearward, increasing the rear axle load; during deceleration, the load shifts forward, decreasing the rear axle load. This load transfer is determined by parameters such as longitudinal acceleration, vehicle mass, center of gravity height, and wheelbase. Superimposing the static axle load with the dynamic transfer yields the current actual rear axle load. This rear axle load is a crucial factor affecting the rear axle lateral stiffness; a larger load results in stronger lateral force generation by the tires, leading to a corresponding change in lateral stiffness. In the field of vehicle dynamics control, estimating axle load using longitudinal acceleration is a mature technique, which will not be elaborated upon here. In this step, the controller acquires the longitudinal acceleration signal collected by the IMU in step S100 and, combined with pre-stored vehicle parameters (including vehicle mass, wheelbase, center of gravity height, and distance from the center of gravity to the front axle), calculates the current rear axle vertical load according to the load transfer principle in vehicle dynamics.

[0065] S403: The average slip ratio is calculated based on the wheel speeds of each wheel and the vehicle speed.

[0066] The controller acquires the wheel speed and vehicle speed of each wheel in step S100, calculates the slip ratio of the left and right rear wheels respectively, and then averages the slip ratios of the two rear wheels to obtain the average slip ratio of the rear axle. This average slip ratio reflects the overall slip level of the rear axle tires. Changes in the slip ratio will change the adhesion state between the tire and the road surface, thus affecting the tire's lateral characteristics. Taking the average slip ratio instead of the slip ratio of a single wheel is to characterize the overall adhesion state of the rear axle, so that the lateral stiffness obtained from the lookup table can represent the equivalent lateral stiffness of the entire rear axle.

[0067] S404: Determine the rear axle lateral stiffness by looking up the data in the pre-stored data table based on the rear axle load and the average slip ratio.

[0068] Using the rear axle load calculated in step S402 and the average slip ratio calculated in step S403 as indexes, the corresponding rear axle lateral stiffness is retrieved from a data table pre-stored in the controller. This data table is pre-calibrated through simulation and real vehicle testing, and records the corresponding values ​​of rear axle lateral stiffness under different combinations of rear axle loads and average slip ratios. The calibration method for this data table is as follows: for the target vehicle platform, under different rear axle load conditions (simulating different loading states such as no load, half load, and full load), and under different rear wheel slip ratio conditions (simulating different driving or braking intensities), the lateral stiffness values ​​of the rear axle tires are measured or simulated and calculated respectively, forming a two-dimensional data table with load and slip ratio as two-dimensional indexes and lateral stiffness as the query result. This data table reflects the nonlinear characteristics of tire lateral stiffness changing with load and slip ratio, and is the basic data source for subsequent table lookup operations. In actual operation, the controller obtains the corresponding lateral stiffness by looking up a table based on the real-time calculated rear axle load and average slip ratio. This ensures calculation accuracy, avoids complex online parameter identification, and has high calculation efficiency, meeting the requirements of real-time control.

[0069] S405: The theoretical steering angle of the rear wheel is obtained by dividing the target lateral force by the rear axle lateral stiffness.

[0070] In this step, the controller will use the target lateral force calculated in step S401. Divide by the rear axle lateral stiffness obtained from the table in step S404 The theoretical steering angle of the rear wheel is obtained. : This theoretical steering angle characterizes the rear wheel steering angle required to generate the target lateral force.

[0071] Furthermore, such as Figure 6 As shown, after step S405 above, the following is also included: S406: Determine whether the theoretical rear wheel steering angle is greater than the steering angle threshold. If so, update the theoretical rear wheel steering angle to the steering angle threshold and then output it; otherwise, output the theoretical rear wheel steering angle directly. That is, use the smaller value between the theoretical rear wheel steering angle and the steering angle threshold as the final target rear wheel steering angle output.

[0072] like ≤ This indicates that the adjustment capability of the active rear-wheel steering system is sufficient to independently achieve the target compensation torque. At this time, the controller directly uses the theoretical rear wheel steering angle. The final target rear wheel steering angle is output to the active rear wheel steering actuator, and the rear wheel steering system can independently complete all compensation tasks without triggering the drive and brake torque adjustment.

[0073] like > This indicates that the adjustment capability of the active rear-wheel steering system has reached saturation and cannot fully achieve the target compensation torque. In this case, the controller will adjust the steering angle threshold. The final target rear wheel steering angle is output to the active rear wheel steering actuator, enabling the rear wheel steering system to achieve as much compensation torque as possible within its capabilities, while simultaneously reducing the difference between the theoretical rear wheel steering angle and the steering angle threshold. - This serves as the basis for calculating the remaining torque, triggering subsequent drive and braking torque adjustment steps.

[0074] The above logic can be uniformly expressed as: based on the theoretical rear wheel steering angle With corner threshold The smaller value in the range is used as the final target rear wheel steering angle output, i.e. =min( , This limiting operation ensures that the commands output to the active rear wheel steering actuator are always within the safe range allowed by the physical actuator and stability boundaries, while reserving the excess torque for subsequent steps.

[0075] Further preferably, if the theoretical rear wheel steering angle exceeds a steering angle threshold, determining the remaining torque based on the difference between the theoretical rear wheel steering angle and the steering angle threshold includes: using the product of the difference, the rear axle lateral stiffness, and the distance from the vehicle's center of gravity to the rear axle as the remaining torque. Specifically, when it is determined in step S406 that the theoretical rear wheel steering angle exceeds the steering angle threshold, the controller first calculates the difference Δδ = - This difference characterizes the magnitude of the rear wheel steering capability gap; the larger the difference, the more compensating torque the rear wheel steering cannot achieve. The controller further uses this difference Δδ and the rear axle lateral stiffness determined by looking up the table in step S404. and the distance from the vehicle's center of gravity to the rear axle pre-stored in the controller The product of these is used as the residual torque. : This calculation method illustrates the rear wheel steering angle notch. Corresponding to the unachieved target lateral force gap = Multiply by the distance from the center of mass to the rear axle This converts the lateral force gap into a yaw moment gap, i.e., the residual moment. This residual moment is the part that has not been compensated after the active rear wheel steering capability has been saturated. In subsequent steps, the drive and brake actuators supplement it by reducing the drive or braking torque of the rear wheel on the high-adhesion side.

[0076] Furthermore, such as Figure 7 As shown, S600 includes: S601: Convert the remaining torque into a reduction in the driving or braking torque of the rear wheel on the high-adhesion side; The controller will handle the remaining torque. Based on the conversion relationship between torque and force, divide by half the wheelbase ( The desired reduction in longitudinal force on the high-adhesion side is obtained by multiplying it by the wheel rolling radius. This translates into a reduction in the driving torque or braking torque of the rear wheel on the side with high adhesion. : This reduction represents the amount of torque that the high-adhesion rear wheel needs to reduce from the current actual driving torque or braking torque in order to compensate for the remaining torque. For driving conditions, this reduction is reflected in a decrease in driving torque; for braking conditions, this reduction is reflected in a decrease in braking torque.

[0077] S602: Perform the torque reduction to reduce the torque of the high-adhesion side rear wheel.

[0078] The controller will calculate the torque reduction amount in step S601. As a correction command, the output is sent to the drive actuator or brake actuator of the rear wheel on the side with high adhesion. Upon receiving the command, the actuator reduces the torque based on the current actual output torque. This reduces the driving or braking torque of the rear wheel on the side with high adhesion. By reducing the torque applied to the rear wheel on the side with high adhesion, the longitudinal force generated by that wheel is reduced, thereby weakening the impact of the excessive longitudinal force generated by the high road adhesion coefficient on the vehicle's yaw motion. This adjustment, together with the output of active rear-wheel steering, ensures that the sum of the yaw moments generated by both equals the target compensation torque, thus achieving yaw stability control of the vehicle during driving or braking on open road surfaces.

[0079] Furthermore, such as Figure 7 As shown, the process of correcting the reduction in torque is also included between step S601 and step S602: S6011: Calculate the driving force request gradient or braking force request gradient based on the vehicle speed and the accelerator pedal position signal / brake pedal position signal.

[0080] Specifically, the controller acquires the current vehicle speed and the accelerator pedal position signal from the accelerator pedal position sensor or the brake pedal position signal from the brake pedal position sensor. Based on these signals, the controller calculates the driver's current driving force request gradient or braking force request gradient. The driving force request gradient characterizes the driver's urgency for acceleration: the faster and deeper the accelerator pedal is depressed, the larger the driving force request gradient, indicating an urgent need for acceleration. Similarly, the braking force request gradient characterizes the driver's urgency for braking: the faster and deeper the brake pedal is depressed, the larger the braking force request gradient, indicating an urgent need for braking. The request gradient can be quantified by the rate of change of the pedal position signal over time (i.e., the amount of change in pedal position per unit time).

[0081] S6012: Determine the gain coefficient based on the vehicle speed and the driving force request gradient or the braking force request gradient; in specific implementation, calculate the gain for different operating conditions. : For braking conditions: Braking gain is obtained by looking up a table based on the gradient of vehicle speed and driver braking request. The principle is that the more urgent the braking request, the lower the gain, so as to sacrifice some yaw stability to ensure braking performance when the driver needs to brake urgently; the faster the vehicle speed, the greater the gain, so as to ensure yaw stability more when braking at high speeds.

[0082] For driving conditions: Drive gain is obtained by looking up a table based on vehicle speed and driver drive request gradient. The principle is that the more urgent the drive request, the lower the gain, the purpose being to sacrifice some yaw stability to ensure power output when the driver has an urgent need for acceleration (such as accelerating to escape a dangerous area); the lower the vehicle speed, the lower the gain, the purpose being to allow some yaw at low speeds or during start-up to ensure sufficient vehicle power to support the vehicle's start-up on open roads. The final amount of wheel torque reduction to be corrected is: ; S6013: Correct the torque reduction amount according to the gain coefficient.

[0083] In this scheme, the torque reduction is corrected by a gain coefficient, enabling the vehicle's control strategy to adaptively adjust according to vehicle speed and driver intent under extreme road conditions, achieving a reasonable balance between yaw stability and longitudinal dynamics / braking efficiency. When the driver has an emergency obstacle avoidance need (rapid acceleration or braking), the system appropriately reduces the priority of yaw stability to ensure longitudinal dynamics; when the vehicle is traveling at high speed, the system increases the priority of yaw stability to ensure driving safety.

[0084] Furthermore, such as Figure 7 As shown, step S602 may include: S6021: Determine whether the longitudinal force of the rear wheel on the high-adhesion side is greater than the longitudinal force of the rear wheel on the low-adhesion side of the same axle.

[0085] Specifically, the controller compares the longitudinal force of the rear wheel on the high-adhesion side with the longitudinal force of the rear wheel on the same axle on the low-adhesion side. If the longitudinal force of the rear wheel on the high-adhesion side is greater than that of the rear wheel on the low-adhesion side (the judgment result is yes), it indicates that there is excess longitudinal force on the rear wheel on the high-adhesion side, and reducing its torque can effectively weaken the yaw effect of the wheel on the high-adhesion side on the vehicle, then step S6022 is executed. If the judgment result is no, it indicates that the longitudinal force of the rear wheel on the high-adhesion side has been reduced to be equal to that of the rear wheel on the low-adhesion side, and adjusting the rear wheels alone can no longer provide the required compensation torque, then step S6023 is executed.

[0086] S6023: Reduces the driving force or braking force of the rear wheel on the side with high adhesion.

[0087] Specifically, the controller outputs a command to the drive actuator or brake actuator of the high-adhesion-side rear wheel to reduce the driving torque or braking torque of that wheel by the torque reduction amount corrected in step S6012, thereby reducing the longitudinal force of the high-adhesion-side rear wheel until it is equal to the longitudinal force of the coaxial low-adhesion-side rear wheel.

[0088] S6023: Determine whether the longitudinal force of the front wheel on the high-adhesion side is greater than the longitudinal force of the front wheel on the low-adhesion side of the same axle.

[0089] Specifically, when the judgment result of step S6021 is negative, the controller further compares the longitudinal force of the current high-adhesion-side front wheel with the longitudinal force of the coaxial low-adhesion-side front wheel. If the longitudinal force of the high-adhesion-side front wheel is greater than the longitudinal force of the low-adhesion-side front wheel (judgment result is positive), it indicates that there is excess longitudinal force on the high-adhesion-side front wheel, and step S6024 is executed. If the judgment result is negative, it indicates that the longitudinal force of the high-adhesion-side front wheel is also equal to that of the low-adhesion-side front wheel, that is, the longitudinal forces of both the front and rear wheels on the high-adhesion side have been sufficiently suppressed, and the controller no longer performs further torque adjustment and directly outputs a command.

[0090] S6024: Reduce the driving force or braking force of the front wheel on the side with high adhesion.

[0091] Specifically, when step S6022 determines that the longitudinal force of the front wheel on the high-adhesion side is greater than the longitudinal force of the front wheel on the coaxial low-adhesion side, the controller outputs a command to the drive actuator or brake actuator of the front wheel on the high-adhesion side to reduce the driving torque or braking torque of the wheel by the torque reduction amount corrected in step S6012, thereby reducing the longitudinal force of the front wheel on the high-adhesion side until it is equal to the longitudinal force of the front wheel on the coaxial low-adhesion side.

[0092] It should be noted that if the judgment result of step S6021 is negative (the longitudinal force of the rear wheel on the high-adhesion side is equal to the longitudinal force of the rear wheel on the low-adhesion side), and the judgment result of step S6023 is also negative (the longitudinal force of the front wheel on the high-adhesion side is also equal to the longitudinal force of the front wheel on the low-adhesion side), it indicates that the longitudinal forces of both the front and rear wheels on the high-adhesion side have been sufficiently suppressed, the longitudinal forces of the left and right wheels have reached a balance, and there is no further room for adjustment in the drive and braking system. At this time, the controller no longer performs any torque reduction operation on any wheel and directly outputs the current control state.

[0093] This implementation employs a rule-based front-to-rear wheel distribution method. Considering that reducing the longitudinal force on the rear axle enhances vehicle yaw stability, insufficient yaw torque is preferentially provided by reducing the braking / driving torque of the high-attachment-side rear wheel. If the torque of the high-attachment-side rear wheel is already equal to that of the low-attachment-side coaxial wheel, the torque of the high-attachment-side front wheel is reduced until it is equal to that of the low-attachment-side coaxial wheel. This scheme adaptively corrects the torque reduction amount through a gain coefficient and executes the torque reduction step-by-step according to the order of "rear wheel priority, front wheel supplementation," enabling the coordinated action of the active rear-wheel steering and the drive / brake actuators to jointly achieve the target compensation torque, effectively maintaining the vehicle's yaw stability during driving or braking on split-road surfaces.

[0094] This application also provides a computer-readable storage medium storing program information. After reading the program information, the computer executes the steps of the split-road vehicle stability control method described in any of the embodiments of the method.

[0095] This application also provides a computer program product, including a computer program / instructions, which, when executed by a processor, implement the steps of the split-road vehicle stability control method described in any of the embodiments of the method.

[0096] This application also provides an electronic device, such as... Figure 8As shown, the electronic device includes at least one processor 81 and at least one memory 82. The at least one memory 82 stores program information. After reading the program information, the at least one processor 81 executes the vehicle stability control method for split-road vehicles described in any of the above method embodiments. The device may further include an input device 83 and an output device 84. The processor 81, memory 82, input device 83, and output device 84 can be communicatively connected. The memory 82, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules. The processor 81 executes various functional applications and data processing by running the non-volatile software programs, instructions, and modules stored in the memory 82, thereby implementing the vehicle stability control method for split-road vehicles provided in any of the above embodiments. The memory 82 may include a program storage area and a data storage area. The program storage area may store the operating system and at least one application program required for a function; the data storage area may store data created based on the use of the vehicle stability control method for split-road vehicles, etc. Furthermore, memory 82 may include high-speed random access memory and non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state memory device. In some embodiments, memory 82 may optionally include memory remotely located relative to processor 81, and these remote memories may be connected via a network to the apparatus performing the split-road vehicle stability control method. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof. Input device 83 may receive user clicks and generate signal inputs related to user settings and function controls of the split-road vehicle stability control method. Output device 84 may include a display device such as a display screen. When the one or more modules are stored in memory 82 and are run by the one or more processors 81, the split-road vehicle stability control method in any of the above method embodiments is executed.

[0097] This application also provides a vehicle that includes the computer-readable storage medium, computer program product, or electronic device described in the foregoing embodiments.

[0098] As needed, the above technical solutions can be combined to achieve the best technical effect.

[0099] The above are merely the principles and preferred embodiments of this application. It should be noted that, for those skilled in the art, several other modifications can be made based on the principles of this application, and these modifications should also be considered within the scope of protection of this application.

Claims

1. A method for controlling vehicle stability on split-road surfaces, characterized in that, include: Obtain vehicle status information, including wheel speed, yaw rate, longitudinal acceleration, driving signals, and vehicle speed; The road surface is identified based on the wheel speeds and vehicle speed, and the side with high adhesion is determined; the ideal yaw rate is determined based on the driving signals and vehicle speed. The feedforward compensation torque is calculated based on the torque balance model, the feedback compensation torque is calculated based on the deviation between the ideal yaw rate and the actual yaw rate, and the target compensation torque is calculated based on the feedforward compensation torque and the feedback compensation torque. The theoretical steering angle of the rear wheels is determined based on the target compensation torque, the longitudinal acceleration, the wheel speeds of each wheel, and the vehicle speed. If the theoretical rear wheel steering angle exceeds the steering angle threshold, the remaining torque is determined based on the difference between the theoretical rear wheel steering angle and the steering angle threshold. The remaining torque is used to adjust the rear wheel on the high-adhesion side.

2. The vehicle stability control method for split-road surfaces according to claim 1, characterized in that, The step of identifying the split road surface and determining the high-adhesion side based on the wheel speeds of each wheel and the vehicle speed includes: Calculate the slip ratio of each wheel based on the wheel speed and the vehicle speed; When the difference in slip ratio between the wheels on both sides of the same axle exceeds a preset threshold, the road surface on which the vehicle is traveling is determined to be a split road surface. The high-adhesion side and low-adhesion side are determined based on the slip ratio of the wheels on both sides of the same axle.

3. The vehicle stability control method for split-road surfaces according to claim 1, characterized in that, The driving signal includes a steering wheel angle signal, and determining the ideal yaw rate based on the driving signal and vehicle speed includes: Based on the steering wheel angle signal and the vehicle speed, the ideal yaw rate is calculated using a pre-stored two-degree-of-freedom vehicle reference model.

4. The vehicle stability control method for split-road surfaces according to claim 1, characterized in that, The calculation of the feedforward compensation torque based on the torque balance model includes: Obtain the driving torque and braking torque fed back by the actuators of each wheel; Based on the driving torque, braking torque, wheel speed, preset wheel moment of inertia, and wheel radius of rotation of each wheel, calculate the longitudinal force of each wheel respectively; The feedforward compensation torque is calculated based on the longitudinal force of each wheel and the preset wheel track.

5. The method for controlling vehicle stability on split-road surfaces according to claim 1, characterized in that, The step of calculating the feedback compensation torque based on the deviation between the ideal yaw rate and the actual yaw rate, and calculating the target compensation torque based on the feedforward compensation torque and the feedback compensation torque, includes: Obtain the pre-calibrated scaling factor Integral coefficient and differential gain coefficient ; Calculate feedback compensation torque : ； in, This indicates the deviation between the ideal yaw rate and the actual yaw rate; The sum of the feedforward compensation torque and the feedback compensation torque is taken as the target compensation torque.

6. The vehicle stability control method for split-road surfaces according to claim 1, characterized in that, The step of determining the theoretical rear wheel steering angle based on the target compensation torque, the longitudinal acceleration, the wheel speeds of each wheel, and the vehicle speed includes: The target lateral force is calculated based on the target compensation torque and the distance from the vehicle's center of gravity to the rear axle; The rear axle lateral stiffness is determined based on the longitudinal acceleration, the wheel speeds of each wheel, and the vehicle speed. The theoretical steering angle of the rear wheel is obtained by dividing the target lateral force by the rear axle lateral stiffness.

7. The method for controlling vehicle stability on split-road surfaces according to claim 6, characterized in that, The determination of the rear axle lateral stiffness based on the longitudinal acceleration, the wheel speeds of each wheel, and the vehicle speed includes: Calculate the rear axle load based on the longitudinal acceleration; The average slip ratio is calculated based on the wheel speeds of each wheel and the vehicle speed. The rear axle lateral stiffness is determined by looking up the data in a pre-stored data table based on the rear axle load and the average slip ratio.

8. The method for controlling vehicle stability on split-road surfaces according to claim 7, characterized in that, The step of determining the rear axle lateral stiffness by looking up a table in a pre-stored data table based on the rear axle load and the average slip ratio includes: The pre-calibrated and stored data table of lateral stiffness corresponding to rear axle load and average slip ratio is used as the pre-stored data table. Using the calculated rear axle load and average slip ratio as indexes, the corresponding rear axle lateral stiffness is retrieved from the pre-stored data table.

9. The method for controlling vehicle stability on split-road surfaces according to claim 1, characterized in that, The step of determining the remaining torque based on the difference between the theoretical rear wheel steering angle and the steering angle threshold if the theoretical rear wheel steering angle exceeds the steering angle threshold also includes: The smaller of the theoretical rear wheel steering angle and the steering angle threshold is used as the final target rear wheel steering angle output.

10. The method for controlling vehicle stability on split-road surfaces according to claim 9, characterized in that, If the theoretical rear wheel steering angle exceeds a steering angle threshold, the remaining torque is determined based on the difference between the theoretical rear wheel steering angle and the steering angle threshold, including: The residual torque is the product of the difference, the rear axle lateral stiffness, and the distance from the vehicle's center of gravity to the rear axle.

11. The method for controlling vehicle stability on split-road surfaces according to claim 1, characterized in that, The method of adjusting the rear wheel on the high-adhesion side using the residual torque includes: The remaining torque is converted into a reduction in the driving or braking torque of the rear wheel on the high-adhesion side; The torque reduction is applied to decrease the torque of the rear wheel on the high-adhesion side.

12. The method for controlling vehicle stability on split-road surfaces according to claim 10, characterized in that, The driving signals include accelerator pedal position signals and brake pedal position signals; after the step of converting the remaining torque into a reduction in the driving or braking torque of the high-adhesion side rear wheel, the method further includes: Calculate the driving force request gradient or braking force request gradient based on the vehicle speed and the accelerator pedal position signal / brake pedal position signal; The gain coefficient is determined based on the vehicle speed and the driving force request gradient or the braking force request gradient. The torque reduction is corrected based on the gain coefficient.

13. A computer-readable storage medium, characterized in that, The storage medium stores program information, and after the computer reads the program information, it executes the steps of the vehicle stability control method for split-road surfaces as described in any one of claims 1-12.

14. A computer program product comprising a computer program / instructions, characterized in that, When the computer program / instructions are executed by the processor, they implement the steps of the vehicle stability control method for split-road surfaces as described in any one of claims 1-12.

15. An electronic device comprising a memory, a processor, and a computer program stored in the memory, characterized in that, The processor executes the computer program to implement the steps of the vehicle stability control method for split-road surfaces as described in any one of claims 1-12.

16. A vehicle, characterized in that, This includes the computer-readable storage medium of claim 13, the computer program product of claim 14, or the electronic device of claim 15.

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