Vehicle body stability control method, device, equipment and computer readable storage medium

Abstract

The application discloses a vehicle body stability control method, device and equipment and a computer readable storage medium, relates to the technical field of automobile control, and the method comprises the following steps: based on a driving state parameter, calculating a mass center side slip angle and a mass center side slip angle change rate of a vehicle; determining a stability state in which the vehicle currently locates; when the vehicle is in a first instability state or a second instability state, controlling a torque vector control system and / or an electronic stability control system to intervene in adjusting the vehicle state until the vehicle returns to a stable driving state. The application adopts a hierarchical intervention mechanism, preferentially starts the torque vector control system to adjust, and only when the torque vector control system reaches an adjustment limit, the electronic stability control system is intervened. The torque vector control system is used as a buffer link, the intervention probability of the electronic stability control system is effectively reduced, the driving experience is improved, and vehicle speed loss is reduced.

Description

Technical Field

[0001] This invention relates to the field of automotive control technology, specifically to a vehicle stability control method, device, equipment, and computer-readable storage medium. Background Technology

[0002] When vehicles are driven under complex conditions, they are prone to instability phenomena such as trajectory deviation, understeer, or oversteer due to factors such as changes in the road surface adhesion coefficient and sudden changes in driver operation. Currently, most mainstream vehicles are equipped with Electronic Stability Control (ESC), which is an extension of the anti-lock braking system and traction control system. It monitors the vehicle's status in real time through wheel speed sensors, yaw rate sensors, and lateral acceleration sensors. When the deviation between the vehicle's actual trajectory and the driver's intention exceeds a threshold, the Electronic Stability Control (ESC) applies independent braking force to specific wheels to generate a corrective yaw moment and reduces engine torque output in coordination to maintain the vehicle's lateral stability.

[0003] However, the Electronic Stability Control (ESC) system only intervenes when the vehicle becomes severely unstable. The intervention process is abrupt, affecting the driving experience and easily causing a loss of vehicle speed. Summary of the Invention

[0004] This invention provides a vehicle stability control method, device, equipment, and computer-readable storage medium, which can solve the technical problem that the intervention process of the electronic stability control system (ESC) in the prior art is abrupt, affecting the driving experience and easily causing vehicle speed loss.

[0005] In a first aspect, embodiments of the present invention provide a vehicle stability control method, comprising the following steps: Collect vehicle driving status parameters, which include at least vehicle speed, vehicle acceleration, steering wheel angle, and actual yaw rate; Based on the driving state parameters, calculate the vehicle's sideslip angle and the rate of change of sideslip angle; The vehicle's current stability state is determined based on the sideslip angle and the rate of change of the sideslip angle. The stability state is divided into: stable driving state, first unstable state and second unstable state. When the vehicle is in the first unstable state or the second unstable state, the torque vector control system and / or electronic stability control system intervene to adjust the vehicle state until the vehicle returns to the stable driving state.

[0006] In conjunction with the first aspect, in one embodiment, determining the current stability state of the vehicle based on the sideslip angle and the rate of change of the sideslip angle includes the following steps: The magnitudes of the centroid sideslip angle and the preset sideslip angle threshold, and the magnitudes of the centroid sideslip angle change rate and the preset sideslip angle change rate threshold are compared respectively. If the sideslip angle of the center of gravity is less than the preset sideslip angle threshold, and the rate of change of the sideslip angle of the center of gravity is less than the preset rate of change of the sideslip angle threshold, then the vehicle is determined to be in the stable driving state. If the sideslip angle of the center of gravity is less than the preset sideslip angle threshold, and the rate of change of the sideslip angle of the center of gravity is greater than or equal to the preset rate of change of the sideslip angle threshold, then the vehicle is determined to be in the first unstable state. If the centroid sideslip angle is greater than or equal to the preset sideslip angle threshold, the vehicle is determined to be in the second instability state.

[0007] In conjunction with the first aspect, in one embodiment, the control torque vector control system and / or electronic stability control system intervene to adjust the vehicle state, including the following steps: Detect the operating status of the torque vector control system and the electronic stability control system; If only the torque vector control system or only the electronic stability control system is working normally, then the torque vector control system or the electronic stability control system that is working normally will intervene to adjust the vehicle state. If both the torque vector control system and the electronic stability control system are working normally, the torque vector control system will be controlled to intervene and adjust the vehicle state first. When the adjustment capability of the torque vector control system reaches the preset limit, the electronic stability control system will then be controlled to intervene and adjust the vehicle state.

[0008] In conjunction with the first aspect, in one embodiment, the torque vector control system, which controls normal operation, intervenes to adjust the vehicle state, including the following steps: The torque vector control system distributes driving torque to the vehicle wheels to adjust the vehicle's state.

[0009] In conjunction with the first aspect, in one implementation, the electronic stability control system, which controls normal operation, intervenes to adjust the vehicle state, including the following steps: The electronic stability control system applies braking force to some of the vehicle's wheels to adjust the vehicle's state.

[0010] In conjunction with the first aspect, in one embodiment, calculating the vehicle's sideslip angle and the rate of change of sideslip angle based on the driving state parameters includes the following steps: The center of gravity sideslip angle is calculated based on the vehicle speed and the steering wheel angle.

[0011] In conjunction with the first aspect, in one embodiment, the step of calculating the vehicle's sideslip angle and sideslip angle change rate based on the driving state parameters further includes the following steps: The longitudinal speed and lateral acceleration are calculated based on the vehicle speed and the vehicle acceleration, respectively. The rate of change of the center of mass sideslip angle is calculated based on the longitudinal vehicle speed, the lateral acceleration, and the actual yaw rate.

[0012] In conjunction with the first aspect, in one implementation, the following steps are also included: When the vehicle is in a stable driving state, the desired yaw rate of the vehicle is calculated based on the vehicle speed and the steering wheel angle. The steer-by-wire system adjusts the steering angle of the vehicle's front wheels so that the actual yaw rate approaches the desired yaw rate.

[0013] In conjunction with the first aspect, in one embodiment, the control steer-by-wire system adjusts the steering angle of the vehicle's front wheels, including the following steps: The steer-by-wire system is controlled to generate a target steering angle for the vehicle's front wheels. The front wheels are driven to rotate based on the target steering angle to adjust the vehicle's actual yaw rate.

[0014] In conjunction with the first aspect, in one implementation, the following steps are also included: The operating status information of the torque vector control system, the electronic stability control system, and the steer-by-wire system is displayed on the vehicle's central control screen.

[0015] In conjunction with the first aspect, in one embodiment, displaying the operating status information of the torque vector control system, the electronic stability control system, and the steer-by-wire system via the vehicle's central control screen includes the following steps: When the torque vector control system, the electronic stability control system, and the steer-by-wire system are all malfunctioning, a malfunction indicator light will be used to warn of the abnormal vehicle stability control function.

[0016] In conjunction with the first aspect, in one embodiment, the acquisition of vehicle driving state parameters, which include at least vehicle speed, vehicle acceleration, steering wheel angle, and actual yaw rate, includes the following steps: The actual yaw rate is measured using a gyroscope or inertial measurement unit.

[0017] Secondly, embodiments of the present invention provide a vehicle stability control device, the vehicle stability control device comprising: The data acquisition unit is used to acquire the vehicle's driving status parameters, which include at least vehicle speed, vehicle acceleration, steering wheel angle, and actual yaw rate. The calculation unit is used to calculate the vehicle's sideslip angle and sideslip angle change rate based on the driving state parameters. The judgment unit is used to determine the current stability state of the vehicle based on the sideslip angle and the rate of change of the sideslip angle. The stability state is divided into: stable driving state, first unstable state and second unstable state. An execution unit is configured to, when the vehicle is in the first unstable state or the second unstable state, control the torque vector control system and / or the electronic stability control system to intervene and adjust the vehicle state until the vehicle returns to the stable driving state.

[0018] Thirdly, embodiments of the present invention provide a vehicle stability control device, the vehicle stability control device including a processor, a memory, and a vehicle stability control program stored in the memory and executable by the processor, wherein when the vehicle stability control program is executed by the processor, it implements the steps of the vehicle stability control method.

[0019] Fourthly, embodiments of the present invention provide a computer-readable storage medium storing a vehicle stability control program, wherein when the vehicle stability control program is executed by a processor, it implements the steps of the vehicle stability control method.

[0020] The beneficial effects of the technical solutions provided by the embodiments of the present invention include: This invention discloses a vehicle stability control method, device, equipment, and computer-readable storage medium. The vehicle stability control method includes the following steps: collecting vehicle driving state parameters, including at least vehicle speed, vehicle acceleration, steering wheel angle, and actual yaw rate; calculating the vehicle's sideslip angle and sideslip angle change rate based on the driving state parameters; determining the vehicle's current stability state based on the sideslip angle and sideslip angle change rate, the stability state being divided into: stable driving state, first instability state, and second instability state; when the vehicle is in the first instability state or the second instability state, intervening in the torque vector control system and / or electronic stability control system to adjust the vehicle state until the vehicle returns to the stable driving state. This invention determines the vehicle's current stability state by calculating the sideslip angle and sideslip angle change rate. A tiered intervention mechanism is adopted, prioritizing the activation of the torque vector control system for adjustment; the electronic stability control system only intervenes when the torque vector control system reaches its adjustment limit. By using a torque vector control system as a buffer, the probability of intervention by the electronic stability control system is effectively reduced, improving the driving experience while reducing vehicle speed loss. Attached Figure Description

[0021] Figure 1 This is a flowchart illustrating the first embodiment of the vehicle stability control method of the present invention; Figure 2 For the present invention Figure 1 A detailed flowchart of step S30; Figure 3 For the present invention Figure 1 A detailed flowchart of step S40; Figure 4 This is a functional module diagram of an embodiment of the vehicle stability control device of the present invention; Figure 5 This is a schematic diagram of the hardware structure of the vehicle stability control device involved in the embodiment of the present invention. Detailed Implementation

[0022] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] like Figure 1 As shown in the figure, an embodiment of the present invention discloses a vehicle stability control method, including the following steps: Step S10: Collect vehicle driving status parameters, which include at least vehicle speed, vehicle acceleration, steering wheel angle and actual yaw rate. Step S20: Based on the driving state parameters, calculate the vehicle's sideslip angle and sideslip angle change rate; Step S30: Determine the current stability state of the vehicle based on the sideslip angle and the rate of change of the sideslip angle. The stability state is divided into: stable driving state, first unstable state and second unstable state. Step S40: When the vehicle is in the first unstable state or the second unstable state, the torque vector control system and / or electronic stability control system intervene to adjust the vehicle state until the vehicle returns to the stable driving state.

[0024] The sideslip angle is a direct indicator of vehicle attitude stability. The size of the sideslip angle directly determines whether the vehicle will experience loss of control such as "drifting" or "spinning".

[0025] The sideslip angle is difficult to measure directly on the entire vehicle. In the linear region of the tire, it is usually calculated using vehicle dynamics models and software algorithms based on the vehicle's steering wheel angle and speed. For the nonlinear region of the tire, the accuracy of the sideslip angle can be improved by using Kalman filtering and observing the transient state of vehicle kinematics. When calculating the sideslip angle, the weights of the dynamics and kinematics model calculations can be dynamically adjusted according to the vehicle's driving conditions. The weight of kinematics is increased at high speeds / sharp turns, while the weight of dynamics is increased during stable cruising conditions.

[0026] Calculate the rate of change of the centroid sideslip angle based on Formula 1: (Formula 1) In the formula, This represents the rate of change of the centroid's sideslip angle. This represents the lateral acceleration of the vehicle, obtained by decomposing the vehicle's acceleration laterally. This represents the vehicle's longitudinal speed, obtained by decomposing the vehicle speed longitudinally. This represents the actual yaw rate.

[0027] The sideslip angle and its rate of change can be used to determine whether the vehicle is currently in a stable driving state, a first instability state, or a second instability state. When the vehicle is in either the first or second instability state, the vehicle stability control scheme is selected based on the current operating status of the Torque Vectoring Control (TVC) and Electronic Stability Control (ESC) systems. When only the TVC or ESC is operating normally, vehicle stability control is prioritized, and the operating TVC or ESC system is used for stability control. When both the TVC and ESC are operating normally, the TVC is activated first for adjustment. Only when the TVC reaches its adjustment limit is the ESC activated to achieve vehicle stability control.

[0028] When both the Torque Vectoring Control (TVC) and Electronic Stability Control (ESC) systems are functioning normally, the TVC is prioritized to adjust the driving torque of the four wheels and actively generate corrective yaw torque. This allows for the suppression of understeer / oversteer without relying on braking deceleration, improving cornering stability at the limits and resistance to loss of control on low-friction surfaces. The TVC reduces the abruptness of the vehicle's dynamics during cornering and bumpy conditions, enhancing cornering comfort and simultaneously ensuring both handling and ride smoothness.

[0029] When the demand for vehicle stability control exceeds the adjustment limits of the torque vectoring control system (TVC), vehicle stability control cannot be achieved solely through adjustments to the TVC. In this case, the electronic stability control system (ESC) needs to intervene to achieve vehicle stability control.

[0030] Furthermore, the adjustment limit of the torque vector control system (TVC) corresponds to the maximum yaw moment that the corresponding TVC can provide. The maximum yaw moment is calculated as follows: the maximum driving torque of the vehicle's single motor is converted into the maximum driving force of the wheel (the driving force of the wheel is related to the adhesion coefficient between the wheel and the road surface), and then the yaw moment around the vehicle's center of gravity is calculated based on the maximum driving force of the four wheels and recorded as the maximum yaw moment.

[0031] While Electronic Stability Control (ESC) offers strong vehicle stability control, its abrupt intervention can negatively impact the driving experience and cause vehicle speed loss. Using ESC as a fallback solution, it only intervenes to maintain vehicle stability when the Torque Vectoring Control (TVC) system reaches its adjustment limits or malfunctions. This effectively reduces the probability of ESC intervention, improving the driving experience while minimizing vehicle speed loss.

[0032] This invention determines the vehicle's current stability state by calculating the sideslip angle and its rate of change. It employs a tiered intervention mechanism, prioritizing the activation of the torque vector control system for adjustment; only when the torque vector control system reaches its adjustment limit does the electronic stability control system intervene. By using the torque vector control system as a buffer, the probability of electronic stability control system intervention is effectively reduced, improving the driving experience while minimizing vehicle speed loss.

[0033] like Figure 2 As shown, in one embodiment, determining the current stability state of the vehicle based on the sideslip angle and the rate of change of the sideslip angle includes the following steps: Step S31: Compare the magnitude of the centroid sideslip angle with the preset sideslip angle threshold, and the magnitude of the centroid sideslip angle change rate with the preset sideslip angle change rate threshold. Step S32: If the center of gravity sideslip angle is less than the preset sideslip angle threshold and the center of gravity sideslip angle change rate is less than the preset sideslip angle change rate threshold, then the vehicle is determined to be in the stable driving state. Step S33: If the center of gravity sideslip angle is less than the preset sideslip angle threshold, and the rate of change of the center of gravity sideslip angle is greater than or equal to the preset sideslip angle rate of change threshold, then the vehicle is determined to be in the first unstable state (belonging to a slight unstable state). Step S34: If the center of gravity sideslip angle is greater than or equal to the preset sideslip angle threshold, the vehicle is determined to be in the second instability state (belonging to a severe instability state).

[0034] The preset sideslip angle threshold is set according to the road surface conditions. The preset sideslip angle threshold is 12° for dry roads and 2° for icy and snowy roads. Furthermore, the preset sideslip angle threshold is an absolute value, corresponding to the sideslip angle in two cases: when the center of gravity velocity direction deflects to one side of the vehicle's longitudinal axis and when the center of gravity velocity direction deflects to the other side of the vehicle's longitudinal axis.

[0035] The preset sideslip angle change rate threshold is set based on the centroid sideslip angle, vehicle speed, and road surface adhesion coefficient. The preset sideslip angle change rate threshold value is within... arrive Between. Furthermore, the preset threshold for the rate of change of the sideslip angle is an absolute value. The corresponding value of the sideslip angle at the center of gravity is continuously increasing in the positive direction, the magnitude of the vehicle's lateral slip is constantly expanding, and the trend of vehicle sideslip is intensifying; the value of the sideslip angle at the center of gravity is continuously increasing in the negative direction.

[0036] The vehicle's current stability state is determined by comparing the center-of-gravity sideslip angle with a preset sideslip angle threshold, and the rate of change of the center-of-gravity sideslip angle with a preset rate of change threshold. When the vehicle is in a stable driving state, the actual yaw rate is corrected through the steer-by-wire (SBW) system, accurately correcting the vehicle's attitude without relying on braking deceleration, thus significantly improving the vehicle's driving stability and trajectory maintenance capability. When the vehicle is in the first or second instability state, the vehicle stability is adjusted through the torque vector control system (TVC) and / or the electronic stability control system (ESC).

[0037] This invention uses the sideslip angle and the rate of change of the sideslip angle as the basis for judging the current stability state of the vehicle, which can accurately obtain the current stability state of the vehicle and provide an accurate basis for judging the vehicle stability control method.

[0038] like Figure 3 As shown, in one embodiment, the control torque vector control system and / or electronic stability control system intervene to adjust the vehicle state, including the following steps: Step S41: Detect the operating status of the torque vector control system and the electronic stability control system; Step S42: If only the torque vector control system or only the electronic stability control system is working normally, then the normally working torque vector control system or the electronic stability control system intervenes to adjust the vehicle state. Step S43: If both the torque vector control system and the electronic stability control system are working normally, the torque vector control system is controlled to intervene and adjust the vehicle state first. When the adjustment capability of the torque vector control system reaches the preset limit, the electronic stability control system is then controlled to intervene and adjust the vehicle state.

[0039] Both the Torque Vectoring Control (TVC) system and the Electronic Stability Control (ESC) system can control vehicle stability. When only the TVC or ESC system is working normally, the TVC or ESC system intervenes to adjust the vehicle state with the aim of achieving vehicle stability control. When both the TVC and ESC systems are working normally, the vehicle stability control objectives are handling comfort and fuel economy. The TVC system first adjusts the vehicle state, and when the TVC system reaches its adjustment limit, the ESC system then intervenes to adjust the vehicle state to achieve vehicle stability control.

[0040] Furthermore, when vehicle stability is controlled through torque vectoring control (TVC) and / or electronic stability control (ESC), steer-by-wire (SBW) also intervenes to control vehicle stability. For example, in high-speed emergency avoidance scenarios (steering wheel angular velocity exceeding a threshold), the vehicle steers sharply, approaching its physical limits. SBW and TVC need to work together simultaneously. SBW actively adjusts the front wheel angle to try and keep the vehicle following a preset avoidance path. Simultaneously, TVC generates yaw moment by distributing torque to counteract the fishtailing tendency caused by sharp steering. By coordinating the intervention of SBW and TVC, and considering the path-following target of SBW, the stability target of TVC, and vehicle energy consumption, an optimal solution is calculated (e.g., reducing SBW steering by 3 degrees while reducing the torque output of TVC by 10%). To achieve optimal vehicle balance, acceleration and steering on icy or snowy roads, and on low-traction surfaces where tires are prone to slippage, the Torque Vectoring Control (TVC) system monitors the slip ratio of each wheel in real time and quickly transfers torque from slipping wheels to wheels with traction, ensuring effective traction. Simultaneously, the Steer-by-Wheel (SBW) system actively adjusts the front wheel angle based on road conditions and vehicle posture to compensate for the steering effects caused by torque distribution.

[0041] In actual vehicle stability control, consider a scenario where a vehicle enters a sharp left-hand bend at approximately 100 km / h on a slippery road surface. The driver, due to excessive speed, sharply steers the vehicle. At this point, the front wheels exceed their traction limits, causing a sideslip, and the front of the vehicle is pushed towards the outside of the bend (towards the guardrail) by centrifugal force. The vehicle's sideslip angle increases dramatically, and the actual yaw rate is lower than the driver's expected value. The driver's action at this moment is to instinctively continue increasing the steering wheel angle (an incorrect action that exacerbates front wheel saturation).

[0042] If insufficient actual yaw rate is detected, the torque vector control system (TVC) is immediately instructed to distribute more torque (e.g., 80%) to the left outer rear wheel (outer side of the bend).

[0043] The left rear wheel receives additional driving force, generating a direct yaw moment pointing inwards into the corner, attempting to "pull" the front of the car back into the corner. Simultaneously, torque vectoring control actively reduces the torque on the right inner rear wheel to prevent it from spinning due to reduced load. Due to the high speed (100 km / h) and slippery road surface, simply increasing driving force has already pushed the left rear wheel close to its traction limit (friction ellipse). The yaw moment provided by the torque vectoring control system (TVC) is insufficient to counteract the enormous inertia, and the vehicle continues to slide outwards.

[0044] When the torque vectoring control system (TVC) fails to pull the yaw rate - sideslip angle state point back to the stable region, the electronic stability control system (ESC) decisively executes asymmetric braking—applying strong braking (lock-up threshold) only to the right rear wheel (the inner rear wheel in the corner). This strong braking of the right rear wheel produces two beneficial effects: the drag resistance of the right rear wheel creates a stronger counter-clockwise yaw moment (left turn of the front of the car) than the TVC, forcibly "bending" the vehicle sliding towards the outside into the corner; and the longitudinal deceleration (negative acceleration) from braking rapidly reduces the vehicle speed, allowing the tires to regain some lateral traction.

[0045] Under the combined action of the torque vector control system (TVC) and the electronic stability control system (ESC), the vehicle's state point is forcibly "pulled" across the safety boundary of the phase plane of the center of gravity sideslip angle and the actual yaw rate, and instantly returns to the inside of the stable region. At this point, the vehicle no longer slides towards the outer guardrail.

[0046] This invention selects the corresponding vehicle stability control strategy based on the operating status of the torque vector control system (TVC) and the electronic stability control system (ESC), which can achieve vehicle stability control while taking into account the needs of handling comfort and energy saving.

[0047] In one embodiment, the torque vector control system, which controls normal operation, intervenes to adjust the vehicle state, including the following steps: controlling the torque vector control system to distribute driving torque to the vehicle wheels to adjust the vehicle state.

[0048] Specifically, the torque vectoring control system (TVC) is used to independently control the output torque of the left and right drive motors. When the vehicle is cornering, the TVC generates an additional yaw moment pointing towards the inside or outside of the curve by differentially distributing drive torque to the inner and outer wheels (e.g., increasing torque on the outer wheels or decreasing torque on the inner wheels). This torque acts directly on the vehicle body to suppress understeer or oversteer tendencies, thereby achieving precise adjustment of the vehicle's stability without relying on the braking system.

[0049] In one embodiment, the electronic stability control system, which controls normal operation, intervenes to adjust the vehicle state, including the following steps: controlling the electronic stability control system to apply braking force to some wheels of the vehicle to adjust the vehicle state.

[0050] Specifically, when the vehicle's stability is determined to be outside the adjustment range of the Torque Vectoring Control (TVC) system or in an emergency situation, the Electronic Stability Control (ESC) system intervenes. Based on the vehicle's current steering characteristics (understeer or oversteer), a target wheel is selected (e.g., braking the outer front wheel in understeer, braking the inner rear wheel in oversteer), and braking torque is applied to the selected target wheel. The braking action on this single wheel generates a yaw moment around the vehicle's center of gravity, forcing the vehicle's actual trajectory back to the ideal path, thereby effectively regulating the vehicle's stability and preventing instability.

[0051] In one embodiment, calculating the vehicle's sideslip angle and sideslip angle change rate based on the driving state parameters includes the following steps: calculating the sideslip angle based on the vehicle speed and the steering wheel angle.

[0052] The sideslip angle is difficult to measure directly on a vehicle. It is usually calculated using vehicle dynamics models and software algorithms based on the vehicle's steering wheel angle and speed. This algorithm has limitations; it is accurate in the linear region of the tires but prone to errors in the nonlinear region. For the nonlinear region of the tires, the accuracy of the sideslip angle can be improved by using Kalman filtering and observing the transient state of vehicle kinematics. When calculating the sideslip angle, the weights of the dynamics and kinematics model calculations can be dynamically adjusted according to the vehicle's driving conditions. At high speeds or during sharp turns, the weight of kinematics is increased; conversely, during stable cruising conditions, the weight of dynamics is increased.

[0053] In one embodiment, the step of calculating the vehicle's sideslip angle and sideslip angle change rate based on the driving state parameters further includes the following steps: calculating the longitudinal vehicle speed and lateral acceleration based on the vehicle speed and the vehicle acceleration, respectively; and calculating the sideslip angle change rate based on the longitudinal vehicle speed, the lateral acceleration, and the actual yaw rate.

[0054] Calculate the rate of change of the centroid sideslip angle based on Formula 1: (Formula 1) In the formula, This represents the rate of change of the centroid's sideslip angle. This represents the lateral acceleration of the vehicle, obtained by decomposing the vehicle's acceleration laterally. This represents the vehicle's longitudinal speed, obtained by decomposing the vehicle speed longitudinally. This represents the actual yaw rate.

[0055] In one embodiment, the method further includes the following steps: when the vehicle is in a stable driving state, calculating the desired yaw rate of the vehicle based on the vehicle speed and the steering wheel angle; controlling the steer-by-wire system to adjust the steering angle of the front wheels of the vehicle so that the actual yaw rate approaches the desired yaw rate.

[0056] In stable driving conditions, such as lane changes and overtaking on the highway, the driver turns the steering wheel, and the steer-by-wire (SBW) system actively adjusts the front wheel angle to allow the vehicle to complete the lane change smoothly and precisely. In this situation, torque vectoring control (TVC) intervention is not required, ensuring smooth driving and improving energy efficiency.

[0057] The desired yaw rate of a vehicle is related to the steering wheel angle and vehicle speed. The desired yaw rate is obtained based on the vehicle dynamics model. The actual yaw rate of the vehicle can be measured by an inertial measurement unit or a gyroscope.

[0058] With a target yaw rate as the objective, when the vehicle is in a stable driving state, the steer-by-wire (SBW) system corrects the actual yaw rate to make it approach the target yaw rate (even if the difference between the actual and target yaw rates is close to zero). Without relying on braking deceleration, it accurately corrects the vehicle's attitude, improving the vehicle's stability and trajectory maintenance capabilities.

[0059] Furthermore, in addition to the steer-by-wire (SBW) system correcting the vehicle's actual yaw rate under normal stable driving conditions, it also corrects the vehicle's actual yaw rate after the vehicle transitions from a first or second instability state to a stable driving state, as the vehicle's state is adjusted through the torque vector control (TVC) and / or electronic stability control (ESC) systems. At this point, although the vehicle is stable, its trajectory is completely erratic. For example, after stabilization, if the vehicle is too close to the inner curb of the curve, without correction, it will run over the curb or crash into an obstacle on the inner curve. At this time, the torque vector control (TVC) and electronic stability control (ESC) systems withdraw high-intensity intervention (retaining only basic damping), and the steer-by-wire (SBW) system takes over trajectory control. The specific control process is as follows: The steer-by-wire (SBW) system calculates a safe, ideal driving trajectory (typically past the apex and pointing towards the exit point) in real time based on the driver's intended steering wheel angle, combined with an onboard high-precision map, a front-facing camera, and an inertial measurement unit. It compares the vehicle's current position with the ideal trajectory; for example, if a lateral deviation of up to 0.8 meters (vehicle leaning inwards) is detected, along with a deviation in the heading angle from the trajectory tangent, the driver's hands may still be tense and stiff on the steering wheel. However, the SBW eliminates this mechanical rigid connection. The steering actuator actively adds a precise "reverse correction angle" (a slight rightward turn) to the angle input by the driver, independent of the driver's feel. The SBW continuously adjusts the front wheel angle hundreds of times per second based on deviations from the pre-aimed distance (50 meters ahead). When the vehicle deviates from the ideal trajectory, it induces a slight understeer tendency through steering adjustment, gently "pushing" the vehicle from the inside curve towards the ideal arc; when approaching the exit point, it automatically straightens the steering wheel, allowing the vehicle to smoothly conform to the exit line.

[0060] This invention improves vehicle stability and trajectory maintenance by using a steer-by-wire (SBW) system to correct the actual yaw rate with the desired yaw rate when the vehicle is in a stable driving state.

[0061] In one embodiment, controlling the steer-by-wire system to adjust the steering angle of the vehicle's front wheels includes the following steps: controlling the steer-by-wire system (SBW) to generate a target steering angle for the vehicle's front wheels; and driving the front wheels to rotate based on the target steering angle to adjust the vehicle's actual yaw rate.

[0062] Real-time monitoring of the vehicle's actual yaw rate. When the difference between the actual yaw rate and the expected yaw rate exceeds a preset threshold (the preset threshold is typically within a certain range), the system will detect the yaw rate. arrive Within the range, it can be set to When a preset threshold is reached (which can be calibrated based on different vehicle models), the steer-by-wire (SBW) intervention logic is activated. Based on the magnitude and direction of the deviation, the required steering angle compensation is calculated, and combined with the driver's basic steering needs, a target steering angle for the vehicle's front wheels is synthesized. The SBW drives the steering motor to rotate, causing the front wheels to precisely turn to the target steering angle. As the front wheel angle changes, the vehicle's motion posture changes. The trend of the difference between the actual yaw rate and the desired yaw rate is continuously monitored. If it is less than the preset threshold, the intervention is maintained or gradually withdrawn; if the deviation is not eliminated, the target steering angle is dynamically updated, forming a closed-loop feedback control.

[0063] In one embodiment, the method further includes the following step: displaying the operating status information of the torque vector control system, the electronic stability control system, and the steer-by-wire system on the vehicle's central control screen.

[0064] In one embodiment, displaying the operating status information of the torque vector control system, the electronic stability control system, and the steer-by-wire system on the vehicle's central control screen includes the following steps: when the torque vector control system, the electronic stability control system, and the steer-by-wire system are all abnormal, a malfunction indicator light is used to warn of the abnormal vehicle stability control function.

[0065] This invention displays the operating status of the Electronic Stability Control (ESC), Torque Vectoring Control (TVC), and Steer-by-Wire (SBW) systems on the vehicle's central control screen, providing timely reminders to the driver. If any of these systems malfunction, a warning light will illuminate indicating that vehicle stability control is unavailable.

[0066] In one embodiment, the driving state parameters include at least vehicle speed, vehicle acceleration, steering wheel angle, and actual yaw rate, including the following steps: measuring the actual yaw rate using a gyroscope or inertial measurement unit.

[0067] like Figure 4 As shown in the figure, an embodiment of the present invention also discloses a vehicle stability control device, the vehicle stability control device comprising: The data acquisition unit is used to acquire the vehicle's driving status parameters, which include at least vehicle speed, vehicle acceleration, steering wheel angle, and actual yaw rate. The calculation unit is used to calculate the vehicle's sideslip angle and sideslip angle change rate based on the driving state parameters. The judgment unit is used to determine the current stability state of the vehicle based on the sideslip angle and the rate of change of the sideslip angle. The stability state is divided into: stable driving state, first unstable state and second unstable state. An execution unit is configured to, when the vehicle is in the first unstable state or the second unstable state, control the torque vector control system and / or the electronic stability control system to intervene and adjust the vehicle state until the vehicle returns to the stable driving state.

[0068] The functions of each module in the above-mentioned vehicle stability control device correspond to the steps in the above-mentioned vehicle stability control method embodiment, and their functions and implementation processes will not be described in detail here.

[0069] like Figure 5 As shown in the figure, the present invention also discloses a vehicle stability control device, which can be a personal computer (PC), a laptop computer, a server or other device with data processing capabilities.

[0070] Reference Figure 5 , Figure 5 This is a schematic diagram of the hardware structure of the vehicle stability control device involved in an embodiment of the present invention. In this embodiment, the vehicle stability control device may include a processor, a memory, a communication interface, and a communication bus.

[0071] The communication bus can be of any type and is used to interconnect the processor, memory, and communication interface.

[0072] Communication interfaces include input / output (I / O) interfaces, physical interfaces, and logical interfaces used for interconnecting components within the vehicle stability control system, as well as interfaces used for interconnecting the vehicle stability control system with other devices (such as other computing devices or user equipment). Physical interfaces can be Ethernet interfaces, fiber optic interfaces, ATM interfaces, etc.; user equipment can be displays, keyboards, etc.

[0073] Memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0074] The processor can be a general-purpose processor, which can call the vehicle stability control program stored in the memory and execute the vehicle stability control method provided in the embodiments of the present invention. For example, the general-purpose processor can be a central processing unit (CPU). The method executed when the vehicle stability control program is called can be referred to in various embodiments of the vehicle stability control method of the present invention, and will not be repeated here.

[0075] Those skilled in the art will understand that Figure 5The hardware structure shown does not constitute a limitation of the invention and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0076] This invention also discloses a computer-readable storage medium.

[0077] The present invention provides a computer-readable storage medium storing a vehicle stability control program, wherein when the vehicle stability control program is executed by a processor, it implements the steps of the vehicle stability control method described above.

[0078] The method implemented when the vehicle stability control program is executed can be referred to in various embodiments of the vehicle stability control method of the present invention, and will not be repeated here.

[0079] It should be noted that the sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0080] The terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such processes, methods, products, or apparatus. The terms "first," "second," and "third," etc., are used to distinguish different objects, etc., and do not indicate a sequence, nor do they limit "first," "second," and "third" to different types.

[0081] In the description of the embodiments of the present invention, terms such as "exemplary," "for example," or "for instance" are used to indicate that they are examples, illustrations, or descriptions. Any embodiment or design that is described as "exemplary," "for example," or "for instance" in the embodiments of the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary," "for example," or "for instance" is intended to present the relevant concepts in a specific manner.

[0082] In the description of the embodiments of the present invention, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. "And / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of the present invention, "multiple" means two or more.

[0083] In some processes described in the embodiments of the present invention, multiple operations or steps are included in a specific order. However, it should be understood that these operations or steps may not be executed in the order they appear in the embodiments of the present invention, or may be executed in parallel. The sequence number of the operation is only used to distinguish different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed sequentially or in parallel, and these operations or steps may be combined.

[0084] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device to execute the methods described in the various embodiments of the present invention.

[0085] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A vehicle stability control method, characterized in that, Includes the following steps: Collect vehicle driving status parameters, which include at least vehicle speed, vehicle acceleration, steering wheel angle, and actual yaw rate; Based on the driving state parameters, calculate the vehicle's sideslip angle and the rate of change of sideslip angle; The vehicle's current stability state is determined based on the sideslip angle and the rate of change of the sideslip angle. The stability state is divided into: stable driving state, first unstable state and second unstable state. When the vehicle is in the first unstable state or the second unstable state, the torque vector control system and / or electronic stability control system intervene to adjust the vehicle state until the vehicle returns to the stable driving state.

2. The vehicle stability control method according to claim 1, characterized in that, The method of determining the current stability state of the vehicle based on the sideslip angle and the rate of change of the sideslip angle includes the following steps: The magnitudes of the centroid sideslip angle and the preset sideslip angle threshold, and the magnitudes of the centroid sideslip angle change rate and the preset sideslip angle change rate threshold are compared respectively. If the sideslip angle is less than the preset sideslip angle threshold and the sideslip angle change rate is less than the preset sideslip angle change rate threshold, then the vehicle is determined to be in the stable driving state. If the sideslip angle is less than the preset sideslip angle threshold, and the sideslip angle change rate is greater than or equal to the preset sideslip angle change rate threshold, then the vehicle is determined to be in the first unstable state. If the centroid sideslip angle is greater than or equal to the preset sideslip angle threshold, the vehicle is determined to be in the second instability state.

3. The vehicle stability control method according to claim 1, characterized in that, The torque vector control system and / or electronic stability control system intervene to adjust the vehicle state, including the following steps: Detect the operating status of the torque vector control system and the electronic stability control system; If only the torque vector control system or only the electronic stability control system is working normally, then the torque vector control system or the electronic stability control system that is working normally will intervene to adjust the vehicle state. If both the torque vector control system and the electronic stability control system are working normally, the torque vector control system will be controlled to intervene and adjust the vehicle state first. When the adjustment capability of the torque vector control system reaches the preset limit, the electronic stability control system will then be controlled to intervene and adjust the vehicle state.

4. The vehicle stability control method according to claim 3, characterized in that, The torque vector control system, which controls normal operation, intervenes to adjust the vehicle state, including the following steps: The torque vector control system distributes driving torque to the vehicle wheels to adjust the vehicle's state.

5. The vehicle stability control method according to claim 3, characterized in that, The electronic stability control system, which controls normal operation, intervenes to adjust the vehicle state, including the following steps: The electronic stability control system applies braking force to some of the vehicle's wheels to adjust the vehicle's state.

6. The vehicle stability control method according to claim 1, characterized in that, The calculation of the vehicle's sideslip angle and sideslip angle change rate based on the driving state parameters includes the following steps: The center of gravity sideslip angle is calculated based on the vehicle speed and the steering wheel angle.

7. The vehicle stability control method according to claim 1, characterized in that, The calculation of the vehicle's sideslip angle and sideslip angle change rate based on the driving state parameters further includes the following steps: The longitudinal speed and lateral acceleration are calculated based on the vehicle speed and the vehicle acceleration, respectively. The rate of change of the center of mass sideslip angle is calculated based on the longitudinal vehicle speed, the lateral acceleration, and the actual yaw rate.

8. The vehicle stability control method according to claim 1, characterized in that, It also includes the following steps: When the vehicle is in a stable driving state, the desired yaw rate of the vehicle is calculated based on the vehicle speed and the steering wheel angle. The steer-by-wire system adjusts the steering angle of the vehicle's front wheels so that the actual yaw rate approaches the desired yaw rate.

9. The vehicle stability control method according to claim 8, characterized in that, The control steer-by-wire system adjusts the steering angle of the vehicle's front wheels, including the following steps: The steer-by-wire system is controlled to generate a target steering angle for the vehicle's front wheels. The front wheels are driven to rotate based on the target steering angle to adjust the vehicle's actual yaw rate.

10. The vehicle stability control method according to claim 8, characterized in that, It also includes the following steps: The operating status information of the torque vector control system, the electronic stability control system, and the steer-by-wire system is displayed on the vehicle's central control screen.

11. The vehicle stability control method according to claim 10, characterized in that, The process of displaying the operating status information of the torque vector control system, the electronic stability control system, and the steer-by-wire system on the vehicle's central control screen includes the following steps: When the torque vector control system, the electronic stability control system, and the steer-by-wire system are all malfunctioning, a malfunction indicator light will be used to warn of the abnormal vehicle stability control function.

12. The vehicle stability control method according to claim 1, characterized in that, The process of collecting vehicle driving status parameters, including at least vehicle speed, vehicle acceleration, steering wheel angle, and actual yaw rate, includes the following steps: The actual yaw rate is measured using a gyroscope or inertial measurement unit.

13. A vehicle stability control device, characterized in that, The vehicle stability control device includes: The data acquisition unit is used to acquire the vehicle's driving status parameters, which include at least vehicle speed, vehicle acceleration, steering wheel angle, and actual yaw rate. The calculation unit is used to calculate the vehicle's sideslip angle and sideslip angle change rate based on the driving state parameters. The judgment unit is used to determine the current stability state of the vehicle based on the sideslip angle and the rate of change of the sideslip angle. The stability state is divided into: stable driving state, first unstable state and second unstable state. An execution unit is configured to, when the vehicle is in the first unstable state or the second unstable state, control the torque vector control system and / or the electronic stability control system to intervene and adjust the vehicle state until the vehicle returns to the stable driving state.

14. A vehicle stability control device, characterized in that, The vehicle stability control device includes a processor, a memory, and a vehicle stability control program stored in the memory and executable by the processor, wherein when the vehicle stability control program is executed by the processor, it implements the steps of the vehicle stability control method as described in any one of claims 1 to 12.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a vehicle stability control program, wherein when the vehicle stability control program is executed by a processor, it implements the steps of the vehicle stability control method as described in any one of claims 1 to 12.

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