Method, device, vehicle and storage medium for controlling a vehicle with a tire blowout
By taking over the control strategy and utilizing the vehicle chassis braking system and electronic power steering motor to adjust the speed and direction of the vehicle with a tire blowout, the problem of loss of steering control after a tire blowout is resolved, and stable control and safe deceleration of the vehicle are achieved.
Patent Information
- Application Number
- CN202211590208.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-12-12
- Publication Date
- 2025-09-09
- Estimated Expiration
- 2042-12-12
AI Technical Summary
Existing technologies make it difficult to effectively control the vehicle's trajectory after a tire blows out, leading to loss of control and safety hazards, especially when the driver operates improperly.
By taking over the control strategy, it utilizes the vehicle's chassis braking system and electronic power steering motor or steer-by-wire motor to generate longitudinal and lateral control strategies, automatically adjusting the vehicle's speed and direction to maintain stability.
It effectively avoids potential risks caused by driver misoperation, ensures that the vehicle decelerates quickly and remains in the original lane, and reduces the possibility of traffic accidents.
Smart Images

Figure CN115771502B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a tire blowout vehicle control technology, and in particular to a tire blowout vehicle control method, a vehicle control device, a vehicle, and a computer-readable storage medium. Background Art
[0002] The moment when a tire blows out while the car is driving at high speed is highly uncertain. If the driver fails to operate in a timely or aggressive manner, the vehicle may lose control or even roll over, which will seriously threaten the lives and property of people in the car and other vehicles.
[0003] Currently, some existing technologies use test data to model the dynamics of certain tire brands after a blowout. Simulations are also performed to analyze the vehicle's kinematic response after a blowout under different operating conditions. Simulation results show that a front tire blowout during straight-line driving can cause severe yaw, while a rear tire blowout during curves can cause the vehicle to spin out of control. Aggressive driver maneuvers can also pose an even greater risk. Regarding vehicle stability control after a blowout, some existing technologies employ electronic stability control (ESC) models. These utilize differential braking to adjust the vehicle's yaw torque after a blowout, preventing loss of directional control. While this technology can achieve a deceleration effect, it cannot restrict the vehicle's trajectory beyond its original lane. There is still a risk of a sudden lane change and collision with other vehicles or pedestrians, posing a significant traffic safety hazard. Summary of the Invention
[0004] In order to solve or at least alleviate one or more of the above problems, the present invention proposes a method for controlling a vehicle with a tire blowout, a vehicle control device, a vehicle, and a computer-readable storage medium, which can reduce the vehicle speed as quickly as possible after a tire blowout and maintain the vehicle's directional stability while avoiding potential risks that may be caused by driver misoperation.
[0005] According to a first aspect of the present invention, a method for controlling a vehicle with a tire blowout is provided, characterized in that it includes the following steps: A. receiving vehicle status information, the vehicle status information including real-time tire pressure and vehicle speed; B. determining whether a driver error has occurred based on trajectory planning information generated by an on-board intelligent driving module and a steering wheel input angle input by the driver, when the tire pressure and the vehicle speed meet specific conditions; and C. if it is determined that a driver error has occurred, generating a first instruction based on a longitudinal control strategy for braking and decelerating the vehicle to a safe speed to output to a longitudinal actuator and generating a second instruction based on a lateral control strategy for maintaining lateral stability of the vehicle to output to a lateral actuator, so as to replace the driver in taking over control of the vehicle.
[0006] As an alternative or supplement to the above solution, in a method according to an embodiment of the present invention, the longitudinal actuator is a brake of a vehicle chassis braking system, and the lateral actuator is an electronic power steering motor or a steer-by-wire motor.
[0007] As an alternative or supplement to the above scheme, in a method according to an embodiment of the present invention, in step B, the tire pressure and the vehicle speed meet specific conditions including: the decrease in the tire pressure during the first time period is greater than or equal to a first threshold; and the vehicle speed is greater than or equal to a second threshold.
[0008] As an alternative or supplement to the above scheme, in a method according to an embodiment of the present invention, step B includes performing the following operations when the tire pressure and the vehicle speed meet specific conditions: B1. Determine the ideal steering wheel angle for the vehicle to travel along the planned trajectory based on the trajectory planning information; B2. Determine the difference between the ideal steering wheel angle and the steering wheel input angle; and B3. If the absolute value of the difference is greater than a third threshold, determine that a driver error has occurred.
[0009] As an alternative or supplement to the above scheme, in a method according to an embodiment of the present invention, step C includes performing the following operations when it is determined that a driver error operation has occurred: C1. If the average value of the vehicle's lateral acceleration during the second time period is greater than a fourth threshold and the average value of the yaw angular velocity is greater than a fifth threshold, then it is determined that the vehicle is in a turning state and control is taken over for the vehicle according to a steering lateral control strategy and a steering longitudinal control strategy; and C2. If the average value of the lateral acceleration during the second time period is less than or equal to the fourth threshold and the average value of the yaw angular velocity is less than or equal to the fifth threshold, then it is determined that the vehicle is in a straight state and control is taken over for the vehicle according to a straight lateral control strategy and a straight longitudinal control strategy.
[0010] As an alternative or supplement to the above scheme, in a method according to an embodiment of the present invention, in step C1, taking over control of the vehicle according to the steering lateral control strategy includes: determining a time domain function of an ideal yaw angular velocity for causing the vehicle to perform uniform deceleration curved motion; determining a mathematical expression for the center line of the lane in which the vehicle is located; substituting the time domain function and the mathematical expression into a single-point preview driver model to obtain a preview deviation between a preview point and the center line of the lane; and inputting the preview deviation as a feedback quantity into a closed-loop controller to make the preview deviation zero and outputting the target steering wheel angle under the preview deviation as the second instruction to the lateral actuator.
[0011] As an alternative to or supplement to the above scheme, in a method according to an embodiment of the present invention, in step C1, taking over control of the vehicle according to the steering longitudinal control strategy includes: determining the position information of the flat tire based on the tire pressure collected by the tire pressure sensor; if the outer front wheel in the steering direction of the vehicle has a flat tire, applying a first proportion of its critical braking pressure to the inner front wheel, applying its critical braking pressure to the outer rear wheel, and determining the braking pressure of the inner rear wheel according to the vertical wheel load ratio of the outer rear wheel and the inner rear wheel; if the inner front wheel in the steering direction of the vehicle has a flat tire, applying a second proportion of its critical braking pressure to the outer front wheel, and applying the critical braking pressure of the outer rear wheel to the outer rear wheel and the inner rear wheel. The minimum value of the critical braking pressure of the inner rear wheel and the critical braking pressure of the inner rear wheel is applied; if the outer rear wheel in the steering direction of the vehicle has a tire burst, a third proportion of its critical braking pressure is applied to the inner front wheel, the braking pressure of the outer front wheel is determined according to the vertical wheel load ratio of the inner front wheel and the outer front wheel, and its critical braking pressure is applied to the inner rear wheel; if the inner rear wheel in the steering direction of the vehicle has a tire burst, its critical braking pressure is applied to the outer rear wheel, and the minimum value of the critical braking pressure of the outer front wheel and the critical braking pressure of the inner front wheel is applied to the outer front wheel and the inner front wheel; wherein, if the braking pressure applied to the corresponding wheel exceeds its critical braking pressure, the corresponding wheel enters a locked state.
[0012] As an alternative or supplement to the above scheme, in a method according to an embodiment of the present invention, in step C2, taking over control of the vehicle according to the straight-ahead lateral control strategy includes: calculating a first steering wheel angle for keeping the vehicle on the center line of the lane based on the vehicle speed, the lateral displacement of the vehicle's center of mass from the center line of the lane, the sideslip angle of the center of mass, and the yaw angle using a single-point preview driver model; performing closed-loop control on the deviation between the yaw angular velocity and a preset yaw angular velocity to obtain a second steering wheel angle; calculating the sum of the first steering wheel angle and the second steering wheel angle as a target steering wheel angle; and outputting the target steering wheel angle as the second instruction to the lateral actuator.
[0013] As an alternative to or supplement to the above scheme, in a method according to an embodiment of the present invention, in step C2, taking over control of the vehicle according to the straight longitudinal control strategy includes: determining position information of the tire with a blowout based on the tire pressure collected by the tire pressure sensor; if one of the two rear wheels has a blowout, applying its critical braking pressure to the rear wheel that has not had a blowout, applying its critical braking pressure to the front wheel on the same side as the rear wheel with the blowout, and determining the braking pressure of the front wheel on the same side as the rear wheel with the blowout according to the vertical wheel load ratio of the two front wheels; if one of the two front wheels has a blowout, applying its critical braking pressure to the front wheel that has not had a blowout, applying its critical braking pressure to the rear wheel on the same side as the front wheel with the blowout, and determining the braking pressure of the rear wheel on the same side as the front wheel with the blowout according to the vertical wheel load ratio of the two rear wheels; wherein, if the braking pressure applied to the corresponding wheel exceeds its critical braking pressure, the corresponding wheel enters a locked state.
[0014] As an alternative or supplement to the above solution, the method according to an embodiment of the present invention further includes: D. when the vehicle speed is less than or equal to the safe speed, exiting the takeover control.
[0015] According to a second aspect of the present invention, a vehicle control device is provided, comprising: a memory; a processor; and a computer program stored on the memory and executable on the processor, wherein the execution of the computer program enables the method according to any embodiment of the first aspect of the present invention to be executed.
[0016] According to a third aspect of the present invention, a vehicle is provided, comprising: an on-board sensor for collecting vehicle status information; and a vehicle control device according to any embodiment of the second aspect of the present invention.
[0017] According to a fourth aspect of the present invention, a computer-readable storage medium is provided, on which program instructions executable by a processor are stored, and when the program instructions are executed by the processor, the method according to any embodiment of the first aspect of the present invention is performed.
[0018] The proposed control scheme for a vehicle with a tire blowout takes over control of the vehicle if it determines driver error, thereby avoiding potential risks caused by overzealous driver manipulation when responding to a tire blowout. Furthermore, the proposed control scheme utilizes a longitudinal control strategy to quickly brake and decelerate the vehicle to a safe speed and a lateral control strategy to maintain its lateral stability. This ensures the vehicle's direction of motion remains stable and allows it to stop quickly, preventing the vehicle from losing control and suddenly changing lanes to collide with other vehicles or obstacles. This significantly reduces the threat to life and property posed by accidental tire blowouts. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The above and / or other aspects and advantages of the present invention will become clearer and easier to understand through the following description of various aspects in conjunction with the accompanying drawings, in which the same or similar elements are represented by the same reference numerals. The drawings include:
[0020] Figure 1 A schematic flow chart of a method 10 for controlling a vehicle with a tire burst according to an embodiment of the present invention is shown;
[0021] Figure 2 A schematic flow chart of a method 20 for controlling a vehicle with a tire burst according to an embodiment of the present invention is shown;
[0022] Figure 3 The simulation results of the center of mass motion trajectory under the condition of right front tire blowout when the vehicle is traveling in a straight line are shown;
[0023] Figure 4 shows the simulation results of the yaw rate under the condition of right front tire blowout when the vehicle is traveling in a straight line; and
[0024] Figure 5 The simulation results of the vehicle speed under the condition of right front tire blowout when the vehicle is traveling in a straight line are shown. DETAILED DESCRIPTION
[0025] In this specification, the present invention is described more fully with reference to the accompanying drawings, which illustrate exemplary embodiments of the present invention. However, the present invention may be embodied in various forms and should not be construed as limited to the embodiments set forth herein. These embodiments are provided to make this disclosure thorough and complete, and to more fully convey the scope of the present invention to those skilled in the art.
[0026] It should be noted that the terms "first," "second," etc. herein are used to distinguish similar objects, and are not necessarily used to describe the order of objects in terms of time, space, size, etc. In addition, unless otherwise specified, the terms "including," "having," and similar expressions herein are intended to indicate non-exclusive inclusion.
[0027] The term "vehicle" or other similar terms herein includes general motor vehicles, such as passenger cars (including sport utility vehicles, buses, trucks, etc.), various commercial vehicles, etc., and includes hybrid electric vehicles, electric vehicles, plug-in hybrid electric vehicles, etc. A hybrid electric vehicle is a vehicle that has two or more power sources, such as gasoline-powered and electric vehicles.
[0028] Hereinafter, exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings.
[0029] Now refer to Figure 1 , Figure 1FIG. 1 is a schematic flow chart of a method 10 for controlling a vehicle with a tire burst according to an embodiment of the present invention. Figure 1 As shown, the method 10 includes the following steps.
[0030] In step S110, vehicle status information is received. For example, the vehicle status information may include one or more of tire pressure, vehicle speed, steering wheel input angle input by the driver, lateral acceleration, yaw rate, and lane information of the vehicle. The vehicle status information may come from various onboard sensors in the vehicle (e.g., tire pressure sensor, inertial measurement unit (IMU), millimeter-wave radar, lidar, monocular / binocular camera), a controller in the vehicle (e.g., electronic control unit (ECU)), or a cloud server.
[0031] In step S120, when the tire pressure and vehicle speed meet specific conditions, it is determined whether the driver has made an erroneous operation based on the trajectory planning information generated by the on-board intelligent driving module and the steering wheel input angle input by the driver.
[0032] Exemplarily, tire blowouts are determined based on tire pressure changes detected by tire pressure sensors. In one example, if tire pressure drops dramatically or slowly, for example, if the decrease in tire pressure during a first period is greater than or equal to a first threshold, then a tire blowout is determined for the corresponding vehicle. In another example, if tire pressure at a certain moment is too low, for example, if the tire pressure is less than or equal to a safe tire pressure, then a blowout can also be considered. Furthermore, if a tire blowout is determined based on tire pressure, the system then determines whether the vehicle with the blowout is traveling at high speed. For example, the system determines whether the vehicle's speed detected by the speed sensor is greater than or equal to a second threshold. It is understood that when a vehicle with a blowout is traveling at high speed, driver error poses a greater safety risk, necessitating further monitoring for driver error. Since a vehicle traveling at high speed often tilts its front end in a certain direction after a tire blowout, resulting in a loss of control, a typical driver error is a large steering wheel turn. It is understood that even a normal vehicle can skid, slip, or even roll over if the steering wheel is turned sharply at high speed, let alone a vehicle with a blowout. Therefore, it is possible to determine whether the driver's erroneous operation after the tire blowout occurs based on the driver's steering wheel input angle after the tire blowout.
[0033] Optionally, in step S120, the following operations are performed when the tire pressure and the vehicle speed meet specific conditions: determining the ideal steering wheel angle for making the vehicle travel along the planned trajectory based on the trajectory planning information; determining the difference between the ideal steering wheel angle and the steering wheel input angle; and if the absolute value of the difference is greater than a third threshold, determining that a driver error has occurred.
[0034] For example, if it is determined that the vehicle with a flat tire is in a high-speed driving state, the vehicle receives trajectory planning information generated by the vehicle's intelligent driving module (e.g., advanced driver assistance system (ADAS)) based on the flat tire working condition, and calculates the ideal steering wheel angle for the vehicle with a flat tire to drive along the planned trajectory based on the trajectory planning information. Next, based on the ideal steering wheel angle and the steering wheel input angle input by the driver The relationship between the size of the two determines whether the driver has made an error. It is understandable that if the driver turns the steering wheel at a large angle after a tire blowout, the ideal steering wheel angle to ensure that the vehicle follows a safe trajectory is The actual steering wheel input angle The difference will suddenly become larger. If the driver's steering wheel input angle and ideal steering wheel angle The difference exceeds the third threshold set in advance ,Right now , it is determined that the driver has made an error in operation and the controller will take over the control of the vehicle instead of the driver.
[0035] In step S130, if it is determined that the driver has made an erroneous operation, a first instruction is generated based on the longitudinal control strategy for braking and decelerating the vehicle to a safe speed to output to the longitudinal actuator, and a second instruction is generated based on the lateral control strategy for maintaining the lateral stability of the vehicle to output to the lateral actuator to take over control of the vehicle instead of the driver.
[0036] As described in the background technology section, some existing technologies use differential braking to adjust the vehicle's yaw moment after a tire blowout, utilizing wheel braking force to prevent directional loss of control. While this technology can achieve deceleration, it cannot limit the vehicle's trajectory beyond its original lane. The present invention creatively proposes applying a longitudinal control strategy to enable a high-speed vehicle to stop quickly after an unexpected tire blowout, while also applying a lateral control strategy to limit the vehicle's trajectory beyond the original lane. This maintains the stability of the vehicle's direction of travel after a tire blowout and prevents the possibility of a sudden lane change and collision with other vehicles or pedestrians.
[0037] Optionally, the longitudinal actuator in step S130 is a brake from the vehicle's chassis braking system, and the lateral actuator is an electronic power steering motor or a steer-by-wire motor. Using an electronic power steering motor, which has only recently become widely used, as an actuator can achieve better vehicle trajectory control. The application of steer-by-wire technology can also achieve active steering, further improving steering efficiency and stability, thereby avoiding potential hazards caused by the driver's erroneous operation after a tire blowout.
[0038] Optionally, method 10 according to one or more embodiments of the present invention applies different control strategies to vehicles traveling in a straight line at high speed and vehicles traveling in a turning direction at high speed, that is, a straight-line lateral control strategy and a straight-line longitudinal control strategy are applied to vehicles traveling in a straight line at high speed, and a turning lateral control strategy and a turning longitudinal control strategy are applied to vehicles traveling in a straight line at high speed.
[0039] Alternatively, the vehicle's position in a straight-ahead state or a turning state can be determined based on the vehicle's lateral acceleration and yaw rate collected by the vehicle's inertial measurement unit (IMU). For example, if the average value of the vehicle's lateral acceleration during the second time period is greater than a fourth threshold value and the average value of the yaw rate is greater than a fifth threshold value, the vehicle is determined to be in a turning state and control is taken over according to the steering lateral control strategy and the steering longitudinal control strategy. Furthermore, if the average value of the lateral acceleration during the second time period is less than or equal to the fourth threshold value and the average value of the yaw rate is less than or equal to the fifth threshold value, the vehicle is determined to be in a straight-ahead state and control is taken over according to the straight-ahead lateral control strategy and the straight-ahead longitudinal control strategy. The following describes the steering lateral control strategy, the steering longitudinal control strategy, the straight-ahead lateral control strategy, and the straight-ahead longitudinal control strategy according to one or more embodiments of the present invention.
[0040] Optionally, in step S130, if it is determined that the vehicle is turning at high speed, the vehicle is taken over according to the following steering lateral control strategy: determining a time domain function of an ideal yaw angular velocity for causing the vehicle to perform uniform deceleration curved motion; determining a mathematical expression for the center line of the lane in which the vehicle is located; substituting the time domain function and the mathematical expression into a single-point preview driver model to obtain a preview deviation between the preview point and the center line of the lane; and inputting the preview deviation as a feedback quantity into a closed-loop controller so that the preview deviation is zero and outputting the target steering wheel angle under the preview deviation as a second instruction to the lateral actuator.
[0041] As described above, the lateral control strategies (i.e., the turning lateral control strategy and the straight-ahead lateral control strategy) according to one or more embodiments of the present invention are designed to keep a vehicle, after a tire blowout, within the lane it was in before the blowout. This prevents the vehicle from losing control of its direction and suddenly changing lanes to collide with other vehicles or obstacles. First, after an unexpected tire blowout while turning, it is desirable for the vehicle to decelerate steadily within its current lane. Assuming a constant turning radius, the ideal yaw rate is a function that decreases over time. This function can be used as the target value for the ideal yaw rate, ensuring that the vehicle maintains a uniform deceleration curve. Second, a mathematical expression for calculating the vehicle's three-dimensional lane centerline can be determined based on existing computer vision technology. This expression can be used as an ideal motion trajectory. By applying it to a single-point preview driver model, the preview deviation from the preview point to the trajectory can be calculated. In summary, the time-domain function of the ideal yaw rate and the mathematical expression of the lane centerline can be used to perform closed-loop control of the lane center offset. That is, the preview deviation is input into the closed-loop controller as feedback, and the preview deviation is adjusted to zero through parameter adjustment. The target steering wheel angle under the preview deviation is output as the second command to the lateral actuator (for example, an electronic power steering motor or a steer-by-wire motor) to ensure that the vehicle remains within the lane centerline during steering.
[0042] Alternatively, in step S130, if it is determined that the vehicle is turning at high speed, the vehicle is taken over and controlled according to the following longitudinal steering control strategy: the position information of the tire with a flat tire is determined based on the tire pressure collected by the on-board sensor; if the outer front wheel in the turning direction of the vehicle has a flat tire, a first proportion of its critical braking pressure (for example, 80% of the critical braking pressure of the inner front wheel) is applied to the inner front wheel, and the critical braking pressure is applied to the outer rear wheel, and the braking pressure of the inner rear wheel is determined according to the vertical wheel load ratio between the outer rear wheel and the inner rear wheel; if the inner front wheel in the turning direction of the vehicle has a flat tire, a second proportion of its critical braking pressure (for example, 100% of the critical braking pressure of the outer front wheel) is applied to the outer front wheel. The method comprises the following steps: applying a third proportion of the critical braking pressure of the inner front wheel to the outer rear wheel (for example, 70% of the critical braking pressure of the inner front wheel) to the inner rear wheel and applying the minimum value of the critical braking pressure of the outer rear wheel and the critical braking pressure of the inner rear wheel to the outer rear wheel; if the outer rear wheel in the turning direction of the vehicle has a tire burst, applying a third proportion of its critical braking pressure (for example, 70% of the critical braking pressure of the inner front wheel) to the inner front wheel, determining the braking pressure of the outer front wheel according to the vertical wheel load ratio of the inner front wheel to the outer front wheel, and applying its critical braking pressure to the inner rear wheel; if the inner rear wheel in the turning direction of the vehicle has a tire burst, applying its critical braking pressure to the outer rear wheel, and applying the minimum value of the critical braking pressure of the outer front wheel and the critical braking pressure of the inner front wheel to the outer front wheel and the inner front wheel.
[0043] It should be noted that the first ratio, the second ratio, and the third ratio mentioned herein are the same or different values greater than 0 and less than 100%. Preferably, the first ratio, the second ratio, and the third ratio are the same or different values greater than 0 and less than or equal to 80%.
[0044] It's also important to note that the critical brake pressure mentioned in this article is very close to the maximum brake pressure at which a wheel would lock. That is, if the brake pressure applied to a wheel exceeds its critical brake pressure, the wheel will lock. The critical brake pressure is the applied brake pressure, calculated by the vehicle controller or anti-lock braking system (ABS) based on the road adhesion coefficient and the vertical wheel load of the corresponding wheel.
[0045] In one example, if the vehicle is turning right and the outer front wheel (i.e., the left front wheel) in the turning direction has a tire blowout, according to the above-mentioned steering longitudinal control strategy, the inner front wheel (i.e., the right front wheel) is applied with its critical braking pressure. 80% of the critical braking pressure is applied to the outer rear wheel (i.e., the left rear wheel) , and the braking pressure of the inner rear wheel is determined according to the vertical wheel load ratio of the outer rear wheel to the inner rear wheel (i.e., the right rear wheel). In this example, if the vertical wheel load of the outer rear wheel is , the vertical wheel load of the inner rear wheel is , then the brake pressure of the inner rear wheel is Similarly, in the event that the outer rear wheel in the direction of vehicle steering has a flat tire, the brake pressure of the outer front wheel can be determined in a similar manner based on the vertical wheel load ratio of the two wheels on the front axle.
[0046] Optionally, in step S130, if it is determined that the vehicle is traveling straight at high speed, the vehicle is taken over for control according to the following straight lateral control strategy: based on the vehicle speed, the lateral displacement of the vehicle's center of mass from the lane center line, the center of mass sideslip angle and the yaw angle, a single-point preview driver model is used to calculate a first steering wheel angle for keeping the vehicle on the lane center line; closed-loop control is performed on the deviation of the yaw angular velocity from a preset yaw angular velocity to obtain a second steering wheel angle; the sum of the first steering wheel angle and the second steering wheel angle is calculated as a target steering wheel angle; and the target steering wheel angle is output as a second instruction to the lateral actuator.
[0047] In order to control the vehicle within the lane it was in after the tire blowout, the lateral displacement of the vehicle's center of mass from the lane centerline generated by the on-board intelligent driving is received. The center of mass side slip angle and yaw angle collected by the inertial navigation and the vehicle speed information collected by the speed sensor can also be obtained. Based on the above information, the single-point preview driver model is used to calculate the first steering wheel angle required to control the vehicle within the lane after the tire blowout. In addition, in order to take comfort into consideration, a yaw rate closed-loop control is introduced. That is, the yaw rate collected by the inertial navigation is compared with the preset yaw rate and the deviation is formed. The deviation is then input into a closed-loop controller (for example, a PID controller). The control effect is adjusted based on the lag-lead correction to obtain the second steering wheel angle required to reduce the yaw rate. , thereby avoiding the driver's panic and discomfort caused by excessive yaw angular velocity. Finally, the target steering wheel angle is obtained by adding the first steering wheel angle and the second steering wheel angle. , which is output as a control command to the lateral actuator (e.g., electronic power steering motor or steer-by-wire motor).
[0048] Optionally, in step S130, if it is determined that the vehicle is traveling straight at high speed, the vehicle is taken over and controlled according to the following straight longitudinal control strategy: the position information of the tire with a blowout is determined based on the tire pressure collected by the on-board sensor; if one of the two rear wheels has a blowout, the critical braking pressure is applied to the rear wheel that has not had a blowout, the critical braking pressure is applied to the front wheel on the same side as the rear wheel with the blowout, and the braking pressure of the front wheel on the same side as the rear wheel with the blowout is determined according to the vertical wheel load ratio of the two front wheels; if one of the two front wheels has a blowout, the critical braking pressure is applied to the front wheel that has not had a blowout, the critical braking pressure is applied to the rear wheel on the same side as the front wheel with the blowout, and the braking pressure of the rear wheel on the same side as the front wheel with the blowout is determined according to the vertical wheel load ratio of the two rear wheels.
[0049] When driving straight, after a tire blows out, the wheel becomes suspended due to the lack of air pressure support, unable to provide vertical force. The sum of the loads on the diagonal of the wheel in question will decrease significantly. Since the vehicle's total mass remains unchanged, the sum of the loads on the other diagonal will increase. This is like a table with four supports suddenly breaking, causing it to tip over with the line connecting the ground contact points of the two adjacent supports serving as the rotation axis. The longitudinal control strategy for straight driving, according to one or more embodiments of the present invention, applies brake pressure to the wheels based on the vertical load ratio of the two coaxial wheels to prevent wheel lock while ensuring braking effectiveness. Due to tire characteristics, wheels with higher vertical loads can generate greater longitudinal adhesion. Therefore, wheels with increased vertical loads after a blowout can be fully utilized to generate sufficient braking force, helping the vehicle decelerate faster. On the other hand, for wheels with reduced vertical loads, brake pressure should be appropriately reduced to prevent wheel lock, loss of steering ability, or spin. Braking pressure should not be applied to wheels with blowouts to prevent the tire from detaching from the rim, creating a safety hazard.
[0050] In one example, if the right front wheel blew out while the vehicle was traveling straight, the wheel load in the left front-right rear wheel diagonal would increase after the blew out, so the right rear wheel would be subjected to its critical braking pressure. The ratio of the vertical load of the left rear wheel to that of the right rear wheel is Apply brake pressure Similarly, in other working conditions where the vehicle is traveling straight and has a tire blowout, the braking pressure can be determined in a similar manner based on the vertical wheel load ratio of the two coaxial wheels.
[0051] Optionally, to prevent a sudden change from driver commands to controller commands after a tire blowout, which could pose a potential safety hazard, in step S130, brake pressure and steering wheel angle can be gradually built up over a short period of time, effectively taking control of the vehicle. Furthermore, given the inertia of mechanical systems in practical applications, excessive dynamic loads and inertial forces can be imposed on the steering system if the steering wheel angle changes too quickly, potentially damaging the mechanical structure. Therefore, amplitude and slope limiting can be added to the steering wheel angle control command.
[0052] Optionally, method 10 further includes step S140: if it is determined in step S120 that no driver error has occurred, generating a first instruction based on a longitudinal control strategy for braking and decelerating the vehicle to a safe speed for output to a longitudinal actuator. If a high-speed vehicle experiences a tire blowout and no driver error has occurred, the driver can continue to control the vehicle laterally, i.e., control the vehicle based on the steering wheel input angle input by the driver. However, conventional brake control strategies do not provide efficient braking after a tire blowout and may also introduce additional vehicle yaw torque, exacerbating vehicle yaw. Therefore, if a high-speed tire blowout occurs, the longitudinal control strategy according to the present invention (e.g., steering longitudinal control strategy, straight-ahead longitudinal control strategy) is immediately activated.
[0053] Optionally, method 10 further includes step S150: when the vehicle speed is less than or equal to the safe speed, exiting takeover control. Taking into account actual road conditions and to prevent the vehicle with a tire blowout from impacting road resources, the driver is allowed to promptly resume control of the vehicle after the speed has dropped to a safe speed, facilitating the driver's ability to move the vehicle with the tire blowout to the side of the road. Since the vehicle speed is very low at this point, the risk of a collision is significantly reduced.
[0054] According to one or more embodiments, method 10 takes over vehicle control when driver error is detected, thereby avoiding potential risks caused by excessive driver control when responding to a tire blowout. Furthermore, according to one or more embodiments, method 10 utilizes a longitudinal control strategy to quickly brake and decelerate the vehicle to a safe speed and a lateral control strategy to maintain the lateral stability of the vehicle. This ensures the vehicle's direction of motion is stable and stops quickly, preventing the vehicle from losing control and suddenly changing lanes to collide with other vehicles or obstacles, significantly reducing the threat to life and property posed by accidental tire blowouts.
[0055] Continue to refer Figure 2 , Figure 2 FIG. 2 is a schematic flow chart of a method 20 for controlling a vehicle with a tire burst according to an embodiment of the present invention. Figure 2 As shown, the method 20 includes the following steps.
[0056] In step S201, a determination is made based on tire pressure information as to whether the vehicle has experienced a tire blowout. For example, if the decrease in tire pressure during a first period is greater than or equal to a first threshold, then a tire blowout is determined for the corresponding vehicle. If a tire blowout is determined, the process proceeds to step S203; otherwise, tire pressure monitoring continues.
[0057] In step S203, a determination is made based on the vehicle speed information to determine whether the vehicle is traveling at a high speed. For example, a determination is made as to whether the vehicle speed, as measured by the speed sensor, is greater than or equal to a second threshold. If the vehicle is traveling at a high speed, the process proceeds to step S205; otherwise, the process returns to step S201.
[0058] In step S205, a determination is made as to whether a driver error has occurred and whether the vehicle is in a straight-ahead or turning state. The process for determining driver error can be found in the description of step S120 above and will not be repeated here. The process for determining the vehicle's driving state can be found in the description of step S130 above and will not be repeated here.
[0059] If it is determined in step S205 that a driver error has occurred and the vehicle is traveling straight, the process proceeds to step S207. In step S207, a first command is generated based on the straight longitudinal control strategy for braking and decelerating the vehicle to a safe speed for output to the longitudinal actuator, and a second command is generated based on the straight lateral control strategy for maintaining lateral stability for output to the lateral actuator, thereby replacing the driver's control of the vehicle.
[0060] If it is determined in step S205 that a driver error has occurred and the vehicle is in a turning state, the process proceeds to step S209. In step S209, a first command is generated based on the longitudinal steering control strategy for braking and decelerating the vehicle to a safe speed, and a second command is generated based on the lateral steering control strategy for maintaining lateral stability, and output to the lateral actuator, thereby replacing the driver in taking over control of the vehicle.
[0061] If it is determined in step S205 that no driver error occurs and the vehicle is in a straight-moving state, the process proceeds to step S211 . In step S211 , a first instruction is generated based on a straight-moving longitudinal control strategy for braking and decelerating the vehicle to a safe speed, and is output to the longitudinal actuator.
[0062] If it is determined in step S205 that no driver error occurs and the vehicle is in a turning state, the process proceeds to step S213 . In step S213 , a first instruction is generated based on a steering longitudinal control strategy for braking and decelerating the vehicle to a safe speed, and is output to the longitudinal actuator.
[0063] The specific implementations of the straight longitudinal control strategy, the straight lateral control strategy, the steering longitudinal control strategy, and the steering lateral control strategy can be referred to the above description of step S130 and will not be repeated here.
[0064] Figure 3-5 The figure shows the simulation results of the right front tire blowout condition when the vehicle is traveling in a straight line. Figure 3-5 The simulation results show the vehicle control effects under the following conditions: applying Method 10 or Method 20 after a tire blowout; not having a tire blowout; no action after the tire blowout; and blind driver control after the tire blowout. Blind driver control means not applying the braking strategy proposed by the present invention, using only the maximum emergency braking pressure of conventional brakes as input, with zero brake pressure on the tire blowout wheel, and immediately returning the steering wheel to the center position after the tire blowout occurs.
[0065] from Figure 3 It can be seen that after a tire blowout, the vehicle using the control method 10 or 20 proposed in the present invention can control the maximum lateral distance of the center of mass from the original trajectory to within 0.015m, which can prevent the vehicle from seriously deviating from the original straight trajectory after a tire blowout and colliding with a guardrail or other vehicles. Figure 4 It can be seen that the control method 10 or 20 of the present invention significantly reduces the fluctuation amplitude of the yaw rate after a tire blowout, thereby improving the comfort of the passengers. Figure 5 It can be seen that the longitudinal control method 10 or 20 of the present invention can effectively brake and decelerate a vehicle with a tire blowout to a safe speed.
[0066] According to a second aspect of the present invention, there is provided a vehicle control device comprising: a memory; a processor; and a computer program stored in the memory and executable on the processor, wherein the execution of the computer program enables Figure 1 Method 10 or Figure 2 The illustrated method 20 is executed.
[0067] According to a third aspect of the present invention, a vehicle is provided, comprising: an on-board sensor for collecting vehicle status information; and a vehicle control device according to any embodiment of the second aspect of the present invention.
[0068] According to a fourth aspect of the present invention, there is also provided a computer readable storage medium storing a computer program, which, when executed by a processor, implements the following Figure 1 Method 10 or Figure 2The computer-readable storage medium may include random access memory (RAM) such as synchronous dynamic random access memory (SDRAM), read-only memory (ROM), non-volatile random access memory (NVRAM), electrically erasable programmable read-only memory (EEPROM), flash memory, other known storage media, etc.
[0069] It should be understood that some of the block diagrams shown in the accompanying drawings of the present invention are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities may be implemented in software, in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.
[0070] It should also be understood that, in some alternative embodiments, the functions / steps included in the aforementioned method may not occur in the order shown in the flowchart. For example, two functions / steps shown in sequence may be performed substantially simultaneously or even in reverse order. This depends on the functions / steps involved.
[0071] Furthermore, those skilled in the art will readily appreciate that the methods for providing driver assistance information provided in one or more of the above-described embodiments of the present invention may be implemented via computer programs. For example, when a computer storage medium (e.g., a USB flash drive) storing the computer program is connected to a computer, running the computer program can execute the methods of one or more of the embodiments of the present invention.
[0072] Although only some embodiments of the present invention have been described above, it will be understood by those skilled in the art that the present invention may be implemented in many other forms without departing from its spirit and scope. Therefore, the examples and embodiments shown are to be considered illustrative rather than restrictive, and the present invention may encompass various modifications and substitutions without departing from the spirit and scope of the present invention as defined in the appended claims.
Claims
1. A method for controlling a vehicle with a tire blowout, characterized in that: The following steps are involved: A. Receive vehicle status information, including real-time tire pressure and vehicle speed; B. determining whether a driver misoperation occurs based on trajectory planning information generated by an onboard intelligent driving module and a steering wheel input angle input by the driver, when the tire pressure and the vehicle speed meet specific conditions; as well as C. if it is determined that a driver error has occurred, generating a first instruction based on a longitudinal control strategy for braking and decelerating the vehicle to a safe speed for output to a longitudinal actuator, and generating a second instruction based on a lateral control strategy for maintaining lateral stability of the vehicle for output to the lateral actuator, so as to take over control of the vehicle in place of the driver; Wherein, step C includes performing the following operations when it is determined that the driver has made an erroneous operation: C1. If during the second time period, the average value of the vehicle lateral acceleration is greater than a fourth threshold value and the average value of the yaw angular velocity is greater than a fifth threshold value, determining that the vehicle is in a turning state and taking over control of the vehicle according to the steering lateral control strategy and the steering longitudinal control strategy; Wherein, in step C1, taking over control of the vehicle according to the steering longitudinal control strategy includes: determining the position information of the flat tire based on the tire pressure collected by the tire pressure sensor; If the outer front wheel in the turning direction of the vehicle has a tire puncture, a first proportion of the critical braking pressure is applied to the inner front wheel, and a first proportion of the critical braking pressure is applied to the outer rear wheel, and the braking pressure of the inner rear wheel is determined according to the vertical wheel load ratio between the outer rear wheel and the inner rear wheel; If the inner front wheel in the direction of vehicle turning has a tire puncture, applying a second proportion of the critical braking pressure of the outer front wheel to the outer front wheel, and applying the minimum value of the critical braking pressure of the outer rear wheel and the critical braking pressure of the inner rear wheel to the outer rear wheel and the inner rear wheel; If the outer rear wheel in the direction of vehicle steering has a tire puncture, a third proportion of the critical braking pressure is applied to the inner front wheel, the braking pressure of the outer front wheel is determined according to the vertical wheel load ratio between the inner front wheel and the outer front wheel, and the critical braking pressure is applied to the inner rear wheel; If the inner rear wheel in the direction of vehicle steering has a tire puncture, the critical braking pressure of the outer rear wheel is applied to the outer rear wheel, and the minimum value of the critical braking pressure of the outer front wheel and the critical braking pressure of the inner front wheel is applied to the outer front wheel and the inner front wheel; If the braking pressure applied to the corresponding wheel exceeds its critical braking pressure, the corresponding wheel enters a locked state.
2. The method according to claim 1, wherein The longitudinal actuator is a brake of a vehicle chassis braking system, and the lateral actuator is an electronic power steering motor or a wire-controlled steering motor.
3. The method according to claim 1, wherein In step B, the tire pressure and the vehicle speed satisfying specific conditions include: The tire pressure decreases by an amount greater than or equal to a first threshold during a first period; and The vehicle speed is greater than or equal to a second threshold.
4. The method according to claim 1, wherein Step B includes performing the following operations when the tire pressure and the vehicle speed meet specific conditions: B1. determining an ideal steering wheel angle for the vehicle to travel along the planned trajectory based on the trajectory planning information; B2. determining a difference between the ideal steering wheel angle and the steering wheel input angle; as well as B3. If the absolute value of the difference is greater than a third threshold, it is determined that a driver erroneous operation has occurred.
5. The method according to claim 1, wherein Step C includes performing the following operations if it is determined that a driver's erroneous operation has occurred: C2. If, during the second time period, the average value of the lateral acceleration is less than or equal to the fourth threshold, and the average value of the yaw angular velocity is less than or equal to the fifth threshold, it is determined that the vehicle is in a straight-ahead state and control of the vehicle is taken over according to the straight-ahead lateral control strategy and the straight-ahead longitudinal control strategy.
6. The method according to claim 1, wherein In step C1, taking over control of the vehicle according to the steering lateral control strategy includes: Determining a time-domain function of an ideal yaw rate for causing the vehicle to perform a uniform deceleration curved motion; Determine a mathematical expression for the centerline of the lane in which the vehicle is located; Substituting the time domain function and the mathematical expression into a single-point preview driver model to obtain a preview deviation between the preview point and the lane centerline; and The preview deviation is input as a feedback quantity into a closed-loop controller to make the preview deviation zero, and a target steering wheel angle under the preview deviation is output as the second instruction to the lateral actuator.
7. The method according to claim 5, wherein: In step C2, taking over control of the vehicle according to the straight-ahead lateral control strategy includes: Calculating a first steering wheel angle to maintain the vehicle in the lane centerline using a single-point preview driver model based on the vehicle speed, the lateral displacement of the vehicle's center of mass from the lane centerline, the sideslip angle, and the yaw angle; performing closed-loop control on a deviation between the yaw angular velocity and a preset yaw angular velocity to obtain a second steering wheel angle; calculating a sum of the first steering wheel angle and the second steering wheel angle as a target steering wheel angle; and The target steering wheel angle is output to the lateral actuator as the second command.
8. The method according to claim 5, wherein In step C2, taking over control of the vehicle according to the straight longitudinal control strategy includes: determining the position information of the flat tire based on the tire pressure collected by the tire pressure sensor; If one of the two rear wheels has a puncture, the critical braking pressure is applied to the rear wheel that has not had a puncture, and the critical braking pressure is applied to the front wheel on the same side as the rear wheel with the puncture, and the braking pressure of the front wheel on the same side as the rear wheel with the puncture is determined according to the vertical wheel load ratio of the two front wheels; If one of the two front wheels has a tire blowout, the critical braking pressure is applied to the front wheel that has not had a tire blowout, and the critical braking pressure is applied to the rear wheel on the same side as the front wheel that has had a tire blowout, and the braking pressure of the rear wheel on the same side as the front wheel that has not had a tire blowout is determined based on the vertical wheel load ratio of the two rear wheels; If the braking pressure applied to the corresponding wheel exceeds its critical braking pressure, the corresponding wheel enters a locked state.
9. The method according to claim 1, wherein The method further comprises: D. When the vehicle speed is less than or equal to the safe speed, exit the takeover control.
10. A vehicle control device, characterized in that: The method comprises: a memory; a processor; and a computer program stored in the memory and executable on the processor, wherein the execution of the computer program causes the method according to any one of claims 1 to 9 to be executed.
11. A vehicle, characterized in that: The vehicle comprises: On-board sensors for collecting vehicle status information; and The vehicle control device according to claim 10.
12. A computer-readable storage medium storing instructions, characterized in that: When the instructions are executed by a processor, the processor is caused to perform the method according to any one of claims 1 to 9.
Citation Information
Patent Citations
Atire burst active braking and adjusting method and system
CN109720336A
Vehicle with braking force distributed by discriminating tire burst from temporary tire
JP2009067359A