Vehicle steering control method, device, equipment, vehicle, medium and product
Patent Information
- Application Number
- CN202611286320.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-24
- Publication Date
- 2026-10-16
AI Technical Summary
[0003]然而，在车辆实际行驶的过程中，受路面干扰、车辆动态参数变化、执行机构误差等因素影响，车辆极易出现过度转向与不足转向的现象，影响行驶安全
[0041] Sixthly, this application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the method described in any of the above aspects.
Smart Images
Figure CN122915243A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of vehicle steering control technology, and in particular to a vehicle steering control method, device, equipment, vehicle, medium, and product. Background Technology
[0002] With the development of vehicle steering control technology, steer-by-wire systems have emerged. Steer-by-wire systems eliminate the mechanical connection between the steering wheel and the front wheels of the vehicle, transmitting the driver's steering intentions through electronic signals. They have the advantages of fast steering response and flexible adjustment of steering characteristics.
[0003] However, during actual driving, due to factors such as road surface interference, changes in vehicle dynamic parameters, and actuator errors, vehicles are prone to oversteering and understeering, affecting driving safety.
[0004] Therefore, how to provide a vehicle steering control method to accurately compensate for vehicle steering deviation has become an urgent technical problem to be solved in the field of vehicle steering control technology. Summary of the Invention
[0005] Based on this, this application addresses the aforementioned technical problems by providing a vehicle steering control method, device, equipment, vehicle, medium, and product that can accurately compensate for vehicle steering deviations.
[0006] In a first aspect, this application provides a vehicle steering control method, including:
[0007] The vehicle's actual yaw rate, actual lateral acceleration, and actual sideslip angle are obtained, and the vehicle's steering state is determined based on the actual yaw rate, actual lateral acceleration, and actual sideslip angle.
[0008] When the vehicle is in an understeer or oversteer state, the actual average wheel angle of the vehicle is corrected according to the vehicle's ideal steering motion parameters, vehicle speed, and rack displacement; the ideal steering motion parameters include ideal yaw rate and / or ideal lateral acceleration.
[0009] Based on the corrected actual average wheel turning angle, the wheels are controlled to steer, and the vehicle's steering state is re-determined based on the re-acquired actual yaw rate, actual lateral acceleration, and actual center of gravity sideslip angle, until the vehicle's steering state is the ideal steering state.
[0010] In the aforementioned vehicle steering control method, the vehicle-side control device can determine the vehicle's steering state based on the actual yaw rate, actual lateral acceleration, and actual sideslip angle. If the vehicle's steering state is understeering or oversteering, the device corrects the vehicle's actual wheel average turning angle. Based on the corrected actual wheel average turning angle, the wheels are controlled to steer, and the actual yaw rate, actual lateral acceleration, and actual sideslip angle are updated in real time. Furthermore, based on the re-acquired actual yaw rate, actual lateral acceleration, and actual sideslip angle, the vehicle's steering state can be re-determined, and the vehicle's actual wheel average turning angle can be corrected again until the vehicle's steering state is ideal. Therefore, this embodiment of the application can dynamically and in a closed loop correct the vehicle's actual wheel average turning angle through the aforementioned iterative control method, thus enabling precise compensation for steering deviations when the vehicle is in an understeering or oversteering state.
[0011] In an optional embodiment of the first aspect, correcting the actual wheel average steering angle of the vehicle based on the vehicle's ideal steering motion parameters, vehicle speed, and rack displacement includes:
[0012] The target wheel average turning angle is determined based on the ideal steering motion parameters and the vehicle speed.
[0013] The difference between the target wheel average turning angle and the actual wheel average turning angle is calculated to obtain the target turning angle difference.
[0014] The rack displacement is adjusted based on the target rotation angle difference, and the actual wheel average rotation angle is corrected based on the adjusted rack displacement.
[0015] In this embodiment, the difference between the target wheel average steering angle and the actual wheel average steering angle can be calculated to obtain the target steering angle difference. Therefore, the actual wheel average steering angle can be corrected based on the target steering angle difference, thus controlling the actual wheel average steering angle to increasingly approach the target wheel average steering angle, thereby achieving... The goal is to achieve the ideal steering state for the vehicle.
[0016] In an optional embodiment of the first aspect, determining the target wheel average steering angle based on the ideal steering motion parameters and the vehicle speed includes:
[0017] Determine whether the vehicle speed is less than a preset vehicle speed threshold;
[0018] If the vehicle speed is less than the preset vehicle speed threshold, the target wheel average turning angle is determined based on the ideal lateral acceleration and the vehicle speed.
[0019] If the vehicle speed is not less than the preset vehicle speed threshold, then the target wheel average turning angle is determined based on the ideal yaw rate and the vehicle speed.
[0020] In this way, the ideal lateral acceleration or ideal yaw rate can be adaptively selected according to whether the vehicle is in a low-speed condition, so as to accurately determine the target wheel's average steering angle.
[0021] In an optional embodiment of the first aspect, determining the steering state of the vehicle based on the actual yaw rate, the actual lateral acceleration, and the actual sideslip angle includes:
[0022] If the actual yaw rate is less than the ideal yaw rate, the actual lateral acceleration is less than the ideal lateral acceleration, and the actual center of mass sideslip angle is greater than the first value, then the steering state is determined to be an understeering state.
[0023] If the actual yaw rate is greater than the ideal yaw rate, the actual lateral acceleration is greater than the ideal lateral acceleration, and the actual center of mass sideslip angle is less than the first value, then the steering state is determined to be an oversteering state.
[0024] If the difference between the actual yaw rate and the ideal yaw rate is less than a first deviation threshold, and the difference between the actual lateral acceleration and the ideal lateral acceleration is less than a second deviation threshold, and the difference between the actual centroid sideslip angle and the first value is less than a third deviation threshold, then the steering state is determined to be an ideal steering state.
[0025] In this embodiment, by comparing the actual yaw rate with the ideal yaw rate, comparing the ideal lateral acceleration with the actual lateral acceleration, and comparing the actual sideslip angle with the first value, the vehicle's steering state can be accurately determined by comprehensively considering the actual yaw rate, the actual lateral acceleration, and the actual sideslip angle.
[0026] In an optional embodiment of the first aspect, the method further includes:
[0027] Get the current gear ratio and steering wheel angle;
[0028] The current linear angle transmission ratio is adjusted based on the rack displacement and the steering wheel angle under the ideal steering state.
[0029] Thus, when the vehicle is in an ideal steering state, the current angular ratio can be accurately determined based on the current vehicle speed, current steering sensitivity, and current yaw rate gain. Consequently, based on the current angular ratio, the actual average wheel angle under ideal steering conditions, and rack displacement, the current linear ratio adapted to different vehicle speeds and steering characteristics can be accurately determined.
[0030] In an optional embodiment of the first aspect, obtaining the current line angle transmission ratio includes:
[0031] The current angular transmission ratio is determined based on the current vehicle speed, current steering sensitivity, and current yaw rate gain.
[0032] The current linear angle transmission ratio is determined based on the current angle-to-angle transmission ratio, the actual average wheel turning angle under the ideal steering state, and the rack displacement.
[0033] In this embodiment, the current line angle transmission ratio is adjusted according to the rack displacement and steering wheel angle under ideal steering conditions. This can align the actual position signal of the steering column and the position of the steering rack, so as to avoid deviation between the steering wheel angle and the actual average wheel angle as much as possible, thereby improving the safety of vehicle driving.
[0034] Secondly, this application also provides a vehicle steering control device, comprising:
[0035] The determination module is used to acquire the vehicle's actual yaw rate, actual lateral acceleration, and actual sideslip angle, and to determine the vehicle's steering state based on the actual yaw rate, actual lateral acceleration, and actual sideslip angle.
[0036] The correction module is used to correct the actual wheel average turning angle of the vehicle based on the vehicle's ideal steering motion parameters, vehicle speed, and rack displacement when the vehicle's steering state is understeer or oversteer; the ideal steering motion parameters include ideal yaw rate and / or ideal lateral acceleration.
[0037] The control module is used to control the wheels to steer based on the corrected actual average wheel turning angle, and to redetermine the vehicle's steering state based on the reacquired actual yaw rate, actual lateral acceleration, and actual center of gravity sideslip angle, until the vehicle's steering state is the ideal steering state.
[0038] Thirdly, this application also provides a vehicle-side control device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of any of the methods described above.
[0039] Fourthly, this application also provides a vehicle including a vehicle-side control device for performing the steps of the method described in any of the above aspects.
[0040] Fifthly, this application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in any of the above aspects.
[0041] Sixthly, this application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the method described in any of the above aspects.
[0042] Regarding the beneficial effects of any of the technical solutions in the second to sixth aspects mentioned above, refer to the beneficial effects of the corresponding technical solutions in the first aspect; repeated examples will not be listed here. Attached Figure Description
[0043] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0044] Figure 1 This is a schematic diagram of an optional application environment for a vehicle steering control method in one embodiment;
[0045] Figure 2 This is a schematic diagram of an optional process for a vehicle steering control method in one embodiment;
[0046] Figure 3 This is a schematic diagram of an optional process for correcting the actual average wheel angle in one embodiment;
[0047] Figure 4 This is an optional flowchart illustrating the step of adjusting the current line angle transmission ratio in another embodiment;
[0048] Figure 5 This is a schematic diagram illustrating the relationship between the angular transmission ratio and vehicle speed in one exemplary embodiment.
[0049] Figure 6 This is a schematic diagram illustrating the relationship between steering sensitivity and vehicle speed in one exemplary embodiment;
[0050] Figure 7 This is a schematic diagram illustrating the relationship between yaw rate gain and vehicle speed in one exemplary embodiment.
[0051] Figure 8 This is a schematic diagram illustrating the relationship between the outer wheel rotation angle, the inner wheel rotation angle, and the rack displacement in an exemplary embodiment.
[0052] Figure 9This is an optional flowchart of a vehicle steering control method in one exemplary embodiment;
[0053] Figure 10 This is a schematic diagram of an optional structure of a vehicle steering control device in one embodiment;
[0054] Figure 11 This is a schematic diagram of an optional internal structure of the vehicle-side control device in one embodiment. Detailed Implementation
[0055] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this application.
[0056] The terms "first," "second," etc., used in this application may be used to describe various elements, but these elements are not limited by these terms. These terms are used only to distinguish the first element from the second element. The terms "comprising" and "having," and any variations thereof, used in this application, are intended to cover non-exclusive inclusion. The term "multiple" used in this application refers to two or more. The term "and / or" used in this application refers to one of the embodiments, or any combination of multiple embodiments.
[0057] With the development of vehicle steering control technology, steer-by-wire systems have emerged. Steer-by-wire systems eliminate the mechanical connection between the steering wheel and the front wheels of the vehicle, transmitting the driver's steering intentions through electronic signals. They have the advantages of fast steering response and flexible adjustment of steering characteristics.
[0058] However, during actual driving, vehicles are prone to oversteering and understeering due to factors such as road surface interference, changes in vehicle dynamic parameters, and actuator errors. Understeering occurs when the vehicle's steering trajectory deviates from the driver's expectations, which can easily lead to skidding; oversteering occurs when the vehicle oversteers, which can easily cause fishtailing. Both of these can affect driving safety.
[0059] Therefore, how to provide a vehicle steering control method to accurately compensate for vehicle steering deviation has become an urgent technical problem to be solved in the field of vehicle steering control technology.
[0060] In one embodiment, such as Figure 1 As shown, a vehicle steering control method is provided. This embodiment illustrates the application of this method to a vehicle-side control device. In this embodiment, the method includes the following steps:
[0061] S101: Obtain the vehicle's actual yaw rate, actual lateral acceleration, and actual sideslip angle, and determine the vehicle's steering state based on these parameters.
[0062] The vehicle can be any vehicle that includes a steer-by-wire system, and the vehicle's steering state includes any one of understeer, oversteer, or ideal steering.
[0063] In this embodiment, the vehicle-side control device can use a yaw rate sensor to collect the actual yaw rate of the vehicle. The actual lateral acceleration of the vehicle is collected using a lateral acceleration sensor. The system also employs a sideslip angle detection module to acquire the vehicle's actual sideslip angle β. Therefore, the vehicle-side control equipment can determine the vehicle's steering state by comparing the actual yaw rate, actual lateral acceleration, and actual sideslip angle with preset parameter thresholds. Optionally, the actual yaw rate, actual lateral acceleration, and actual sideslip angle can each correspond to different preset parameter thresholds, or they can correspond to the same preset parameter threshold.
[0064] S102, when the vehicle is in an understeer or oversteer state, corrects the actual wheel average turning angle of the vehicle based on the vehicle's ideal steering motion parameters, vehicle speed, and rack displacement.
[0065] Among them, vehicle speed refers to the longitudinal speed v of the vehicle. x The ideal steering motion parameters of a vehicle include ideal yaw rate and / or ideal lateral acceleration.
[0066] In this embodiment, the vehicle-side control device can use a vehicle speed sensor to collect the vehicle speed at a certain sampling frequency, and use a TAS sensor (Torque and Angle Sensor) from the up-and-down steering module to determine the rack displacement l of the front wheel steering gear according to the sampling frequency. For example, the sampling frequency can be greater than or equal to 100Hz. Furthermore, the vehicle-side control device can also acquire the actual average wheel steering angle of the vehicle in real time.
[0067] Therefore, when the vehicle-side control equipment determines that the vehicle's steering state is understeer or oversteer, it can correct the actual average wheel angle based on the vehicle's ideal steering motion parameters, vehicle speed, and rack displacement. Optionally, the vehicle-side control equipment can directly correct the real-time acquired actual average wheel angle based on the vehicle's ideal steering motion parameters, vehicle speed, and rack displacement; or, the vehicle-side control equipment can determine the target average wheel angle based on the vehicle's ideal steering motion parameters and vehicle speed, and then correct the real-time acquired actual average wheel angle based on the target average wheel angle and rack displacement.
[0068] Optionally, the vehicle-side control equipment can also monitor the operating status of various sensors and actuators (such as motors, steering gears, etc.) in real time, and design fault-tolerant strategies to ensure the effectiveness of the aforementioned correction process in the event of a failure of any sensor and / or actuator. For example, if at least one of the sensors such as the TAS sensor, vehicle speed sensor, yaw rate sensor, and lateral acceleration sensor fails or displays distorted information, the data acquisition function of the failed sensor can be shut down. If any actuator fails, its execution function can be shut down. In this way, safety hazards can be minimized as much as possible when sensors and / or actuators fail.
[0069] S103 controls the wheels to steer based on the corrected actual average wheel angle, and redetermines the vehicle's steering state based on the reacquired actual yaw rate, actual lateral acceleration, and actual center of gravity sideslip angle, until the vehicle's steering state is the ideal steering state.
[0070] In this embodiment, as the vehicle is actually driven, its actual yaw rate, actual lateral acceleration, and actual center of gravity sideslip angle are constantly changing due to changes in weight distribution, tire wear, and road surface adhesion. Therefore, in order to keep the vehicle in an ideal steering state, it is necessary to update the actual yaw rate, actual lateral acceleration, and actual center of gravity sideslip angle.
[0071] Based on this, the vehicle-side control equipment can control the wheels to steer according to the corrected actual average wheel steering angle. After controlling the wheels to steer, it reacquires the actual yaw rate, actual lateral acceleration, and actual sideslip angle. Therefore, based on the reacquired actual yaw rate, actual lateral acceleration, and actual sideslip angle, the vehicle-side control equipment can redetermine the vehicle's steering state, i.e., return to execute S101, and then re-correct the vehicle's actual average wheel steering angle. This process is iterated until the vehicle's steering state is determined to be the ideal steering state, at which point the correction of the vehicle's actual average wheel steering angle stops.
[0072] In the aforementioned vehicle steering control method, the vehicle-side control device can determine the vehicle's steering state based on the actual yaw rate, actual lateral acceleration, and actual sideslip angle. If the vehicle's steering state is understeer or oversteer, the device corrects the vehicle's actual wheel average turning angle. Based on the corrected actual wheel average turning angle, the wheels are controlled to steer, and the actual yaw rate, actual lateral acceleration, and actual sideslip angle are updated in real time. Furthermore, based on the re-acquired actual yaw rate, actual lateral acceleration, and actual sideslip angle, the vehicle's steering state can be re-determined, and the vehicle's actual wheel average turning angle can be corrected again until the vehicle's steering state is ideal. Therefore, this embodiment of the application can dynamically and in a closed loop correct the vehicle's actual wheel average turning angle through the aforementioned iterative control method, thus enabling precise compensation for steering deviations when the vehicle is in an understeer or oversteer state.
[0073] In one embodiment, such as Figure 2 As shown, a method for determining the steering state of a vehicle is provided, namely, "determining the steering state of the vehicle based on the actual yaw rate, actual lateral acceleration, and actual sideslip angle" in S101 above, including:
[0074] S201, compare the actual yaw rate with the ideal yaw rate, compare the ideal lateral acceleration with the actual lateral acceleration, and compare the actual center of mass sideslip angle with the first value.
[0075] S202, if the actual yaw rate is less than the ideal yaw rate, the actual lateral acceleration is less than the ideal lateral acceleration, and the actual center of gravity sideslip angle is greater than the first value, then the steering state is determined to be understeering.
[0076] S203, if the actual yaw rate is greater than the ideal yaw rate, the actual lateral acceleration is greater than the ideal lateral acceleration, and the actual center of gravity sideslip angle is less than the first value, then the steering state is determined to be an oversteering state.
[0077] S204, if the difference between the actual yaw rate and the ideal yaw rate is less than the first deviation threshold, and the difference between the actual lateral acceleration and the ideal lateral acceleration is less than the second deviation threshold, and the difference between the actual center of gravity sideslip angle and the first value is less than the third deviation threshold, then the steering state is determined to be the ideal steering state.
[0078] In this embodiment, the vehicle-side control device can pre-acquire relevant vehicle parameters. For example, the relevant vehicle parameters may include, but are not limited to, the vehicle's wheelbase L, the vehicle's mass m, and the front wheel's lateral stiffness C. f lateral stiffness of the rear wheel The distances from the vehicle's center of gravity to the front axle (a) and from the center of gravity to the rear axle (b) are calculated. Furthermore, the vehicle-side control equipment can simulate and calculate the ideal vehicle speed (v), and use the TAS sensors in the up and down steering modules to determine the steering wheel angle. And obtain the actual average wheel angle of the front wheels. Therefore, the vehicle-side control equipment can be based on a two-degree-of-freedom vehicle dynamics model, relevant vehicle parameters, ideal vehicle speed v, and steering wheel angle. and the actual average steering angle of the front wheels The ideal yaw rate is determined using the following formula (1). And the ideal lateral acceleration is determined by the following formula (2). .
[0079] (1)
[0080] (2)
[0081] in, Indicates the yaw rate gain. Indicates steering sensitivity.
[0082] Furthermore, the ideal steering motion parameters can be adaptively adjusted for different vehicles. For example, in sports models, the ideal steering motion parameters can be set smaller during the understeer determination process to ensure sporty characteristics; while in the vehicle's sport mode or drift mode, the ideal steering motion parameters can be set larger during the oversteer determination process to increase oversteer characteristics.
[0083] Therefore, when the vehicle is in a stable circular operating condition rather than a transient transitional operating condition, the vehicle-side control equipment can compare the actual yaw rate with the ideal yaw rate, compare the ideal lateral acceleration with the actual lateral acceleration, and compare the actual sideslip angle with the first value. If the actual yaw rate is less than the ideal yaw rate (i.e., ... < ), and the actual lateral acceleration is less than the ideal lateral acceleration (i.e. < If the actual center of gravity sideslip angle β is greater than the first value, the vehicle-side control equipment can determine that the steering state is understeering. At this time, the vehicle is at risk of understeer and the turning radius continues to increase.
[0084] If the actual yaw rate is greater than the ideal yaw rate (i.e.) > ), and the actual lateral acceleration is greater than the ideal lateral acceleration (i.e. > If the actual sideslip angle β is less than the first value, then the steering state is determined to be oversteer, at which point the vehicle is at risk of fishtailing. If the sideslip angle change rate is also determined... If the rate of change continues to exceed the preset threshold, it indicates that the vehicle has a greater risk of fishtailing and instability.
[0085] If the actual yaw rate With ideal yaw rate The difference between them is less than the first deviation threshold, and the actual lateral acceleration Compared with ideal lateral acceleration If the difference between the values is less than the second deviation threshold, and the difference between the actual centroid sideslip angle β and the first value is less than the third deviation threshold, then the steering state is determined to be the ideal steering state. At this time, there is no need to compensate for the actual average wheel angle of the vehicle; only the dynamic transmission ratio needs to be maintained.
[0086] For example, the first value can be 0, β > 0 indicates that the center of gravity is biased towards the inside of the steering wheel, and β < 0 indicates that the center of gravity is biased towards the outside of the steering wheel. The preset rate of change threshold, the first deviation threshold, the second deviation threshold, and the third deviation threshold can all be calibrated according to relevant vehicle parameters. For example, the first deviation threshold can be ±0.05° / s, the second deviation threshold can be 0.05g, and the third deviation threshold can be 0 ± 0.05° / s.
[0087] In this embodiment, by comparing the actual yaw rate with the ideal yaw rate, comparing the ideal lateral acceleration with the actual lateral acceleration, and comparing the actual sideslip angle with the first value, the vehicle's steering state can be accurately determined by comprehensively considering the actual yaw rate, the actual lateral acceleration, and the actual sideslip angle.
[0088] In one embodiment, such as Figure 3 As shown, a method for correcting the actual average wheel steering angle is provided, namely, "correcting the actual average wheel steering angle of the vehicle based on the vehicle's ideal steering motion parameters, vehicle speed, and rack displacement" in S102 above, including:
[0089] S301 determines the target wheel average turning angle based on the ideal steering motion parameters and vehicle speed.
[0090] In this embodiment of the application, optionally, the vehicle-end control device can determine the average steering angle of the target wheel based on the ideal yaw rate and the vehicle speed; or, the vehicle-end control device can also determine the average steering angle of the target wheel based on the ideal lateral acceleration and the vehicle speed; or, the vehicle-end control device can also determine the first weight corresponding to the ideal yaw rate and the second weight corresponding to the ideal lateral acceleration based on the vehicle speed and the correspondence between the vehicle speed and the weight, thereby determining the average steering angle of the target wheel based on the ideal yaw rate, the first weight, the ideal lateral acceleration, the second weight, and the vehicle speed.
[0091] In one alternative embodiment, S301 includes:
[0092] Determine if the vehicle speed is less than the preset speed threshold.
[0093] If the vehicle speed is less than the preset vehicle speed threshold, the average turning angle of the target wheel is determined based on the ideal lateral acceleration and vehicle speed.
[0094] If the vehicle speed is not less than the preset vehicle speed threshold, the average turning angle of the target wheel is determined based on the ideal yaw rate and the vehicle speed.
[0095] In this embodiment, the vehicle-side control device can determine whether the vehicle speed is less than a preset vehicle speed threshold. For example, the preset vehicle speed threshold could be 40 km / h. If the vehicle speed is less than the preset vehicle speed threshold, it indicates that the vehicle is in a low-speed operating condition. The vehicle-side control device can then use the following formula (3) based on the ideal lateral acceleration... Vehicle-related parameters and speed v x Determine the average steering angle of the target wheel. If the vehicle speed is not less than the preset vehicle speed threshold, it means that the vehicle is not in a low-speed condition. In this case, the vehicle-side control device can use the following formula (4) based on the ideal yaw rate. Vehicle-related parameters and speed v x Determine the average steering angle of the target wheel. .
[0096] (3)
[0097] (4)
[0098] In this way, the ideal lateral acceleration or ideal yaw rate can be adaptively selected according to whether the vehicle is in a low-speed condition, so as to accurately determine the target wheel's average steering angle.
[0099] S302, calculate the difference between the target wheel average turning angle and the actual wheel average turning angle to obtain the target turning angle difference.
[0100] In this embodiment of the application, the vehicle-end control device can use the following formula (5) to calculate the average turning angle of the target wheel. Compared with the actual average wheel angle Perform the difference calculation to obtain the target turning angle difference. .
[0101] - (5)
[0102] In the formula, if A value less than 0 indicates that the vehicle is understeering. This indicates that the vehicle is in an ideal steering state. Therefore, the embodiments of this application are based on... Steering control is applied to the target. Among other things, This is just an example; actual calibration should be performed based on the vehicle's relevant parameters. This indicates that the vehicle is in an oversteering state.
[0103] S303 adjusts the rack displacement based on the target angle difference and corrects the actual wheel average angle based on the adjusted rack displacement.
[0104] In this embodiment, the vehicle-side control device can control the steering gear to move the rack based on the target steering angle difference and in conjunction with the PID control algorithm (Proportional-Integral-Derivative Control). This allows for adjustment of the rack displacement, thereby correcting the actual average wheel steering angle based on the adjusted rack displacement.
[0105] Optionally, the P (proportional), I (integral), and D (derivative) values in the PID control algorithm can be adjusted based on the actual yaw rate, actual lateral acceleration, actual sideslip angle, and vehicle speed. For example, if The larger the value, the larger the P-value can be set.
[0106] Furthermore, to ensure the vehicle's driving state remains stable and to guarantee driving safety, angle compensation limits can be applied based on vehicle speed conditions (low / medium / high speed). For example, when the vehicle is operating at low speed, such as v... x For speeds ≤40km / h, the compensation angle range can be set to -3° to 3°, and the response speed can be set to 40° / s. When the vehicle is operating at medium speeds, such as 40km / h < v... x For speeds <80km / h, the compensation angle range can be set to -2° to 2°, and the response speed can be set to 30° / s. When the vehicle is in high-speed operating conditions, such as v xFor speeds ≥80km / h, the compensation angle range can be set to -1° to 1°, and the response speed can be set to 10° / s. The values in this embodiment are merely examples and can be calibrated according to the vehicle's relevant parameters.
[0107] In this embodiment, the difference between the target wheel average steering angle and the actual wheel average steering angle can be calculated to obtain the target steering angle difference. Therefore, the actual wheel average steering angle can be corrected based on the target steering angle difference, thus controlling the actual wheel average steering angle to increasingly approach the target wheel average steering angle, thereby achieving... The goal is to achieve the ideal steering state for the vehicle.
[0108] In one embodiment, such as Figure 4 As shown, a method for adjusting the current linear angle transmission ratio after S103 is provided, that is, the method further includes:
[0109] S401, obtain the current linear gear ratio and steering wheel angle.
[0110] In this embodiment, the vehicle-side control device can use the TAS sensor of the up and down steering module to determine the steering wheel angle. Furthermore, the vehicle-side control equipment can acquire relevant vehicle parameters and the actual average steering angle of the front wheels. Based on the vehicle's relevant parameters and the actual average steering angle of the front wheels, Determine the current linear angle transmission ratio.
[0111] In one optional embodiment, "obtaining the current line angle transmission ratio" in S401 includes:
[0112] The current angular transmission ratio is determined based on the current vehicle speed, current steering sensitivity, and current yaw rate gain.
[0113] The current linear gear ratio is determined based on the current angle-to-angle transmission ratio, the actual average wheel turning angle under ideal steering conditions, and the rack displacement.
[0114] In the design of online steering systems, a variable gear ratio is generally used, meaning the gear ratio changes with vehicle speed. For example, a small gear ratio is used at low speeds and a large gear ratio is used at high speeds, thereby improving the vehicle's responsiveness at low speeds and its stability at high speeds. For example, ... Figure 5 As shown, Figure 5 This is a schematic diagram illustrating the relationship between the yaw rate and vehicle speed in an exemplary embodiment. In a steer-by-wire system, changes in the gear ratio primarily affect the vehicle's yaw rate gain and steering sensitivity. For example,... Figure 6 As shown, Figure 6 This is a schematic diagram illustrating the relationship between steering sensitivity and vehicle speed in an exemplary embodiment; as shown below. Figure 7 As shown, Figure 7 This is a schematic diagram illustrating the relationship between yaw rate gain and vehicle speed in one exemplary embodiment.
[0115] In this embodiment, when the vehicle is in an ideal steering state, the vehicle-side control device can acquire the current vehicle speed V in real time and determine whether the current vehicle speed V is less than a preset vehicle speed threshold. For example, the preset vehicle speed threshold can be 40 km / h. If the current vehicle speed V is less than the preset vehicle speed threshold, it indicates that the vehicle is in a low-speed condition. The vehicle-side control device can then use the following formula (6) based on the current steering sensitivity... Based on the relevant parameters of the vehicle and the current vehicle speed V, determine the current yaw rate i. If the current vehicle speed V is not less than the preset vehicle speed threshold, it indicates that the vehicle is not in a low-speed condition. In this case, the vehicle-side control device can use the following formula (7) to determine the yaw rate i based on the current yaw rate gain. Based on the vehicle's relevant parameters and current speed V, determine the current angular transmission ratio i.
[0116] (6)
[0117] (7)
[0118] The angle-to-angle transmission ratio represents the steering wheel angle. Compared with the actual average wheel angle of the front wheels The ratio, i.e. .
[0119] Therefore, the vehicle-side control equipment can use the TAS sensor of the up and down steering module to determine the rack displacement l of the front wheel steering gear according to the acquisition frequency. Also, the following formula (8) can be used, based on the actual inner wheel rotation angle of the vehicle. and the actual outer wheel angle of the vehicle Determine the actual average wheel angle under ideal steering conditions. .
[0120] (8)
[0121] Based on this, the vehicle-end control device can adopt the following formulas (9)-(10), according to the current angular transmission ratio i and the actual average wheel turning angle under the ideal steering state. Determine the current linear angle transmission ratio based on the rack displacement l. .
[0122] (9)
[0123] (10)
[0124] Where K represents the transmission ratio of the trapezoidal mechanism of the front suspension, and K is a characteristic determined by the hard point of the suspension system, representing the current line angle transmission ratio under ideal steering conditions. The line angle transmission ratio expressed is the theoretically calculated line angle transmission ratio (hereinafter referred to as the theoretical line angle transmission ratio).
[0125] For example, such as Figure 8 As shown, Figure 8 This is a schematic diagram illustrating the relationship between the outer wheel rotation angle, the inner wheel rotation angle, and the rack displacement in an exemplary embodiment. Based on this, the rack displacement l can be determined by K, which is determined by the suspension hardpoint. Therefore, the rack displacement l and... Figure 8 The relationship between the inner wheel rotation angle and the outer wheel rotation angle is obtained. Furthermore, the actual inner wheel rotation angle of the vehicle in equation (8) can be verified through the relationship between the inner wheel rotation angle and the outer wheel rotation angle. and the actual outer wheel angle of the vehicle The accuracy.
[0126] Thus, when the vehicle is in an ideal steering state, the current angular ratio can be accurately determined based on the current vehicle speed, current steering sensitivity, and current yaw rate gain. Consequently, based on the current angular ratio, the actual average wheel angle under ideal steering conditions, and rack displacement, the current linear ratio adapted to different vehicle speeds and steering characteristics can be accurately determined.
[0127] S402 adjusts the current linear angle transmission ratio based on the rack displacement and steering wheel angle under ideal steering conditions.
[0128] In this embodiment of the application, due to the wheel... The change in the actual average wheel angle A change has occurred; the rack position has changed, meaning the rack displacement has increased. But the steering wheel angle Since nothing has changed, both the angular ratio and the linear ratio have changed. Based on this, to ensure that the actual position signal of the steering column's steering wheel is aligned with the position of the steering gear's rack, the vehicle-side control device can use the following formula (11), based on the rack displacement under ideal steering conditions. and steering wheel angle Adjust the current linear angle transmission ratio The adjusted real-time linear angle transmission ratio is obtained. .
[0129] (11)
[0130] At this point, the current linear angle transmission ratio can be... Adjusted to Once the steering wheel has been turned to the center position (i.e., aligned with the steering wheel), the adjusted real-time linear gear ratio can be adjusted. Reset to the theoretical linear angle transmission ratio.
[0131] In this embodiment, the current line angle transmission ratio is dynamically adjusted based on the rack displacement and steering wheel angle under ideal steering conditions. This aligns the actual position signal of the steering column and the position of the steering rack, minimizing deviations between the steering wheel angle and the actual average wheel angle, thereby improving vehicle safety. This allows for coordinated operation of the line angle transmission ratio adjustment and the compensation for the actual average wheel angle, minimizing compensation failure caused by a disconnect between the line angle transmission ratio and the actual average wheel angle, thus enhancing steering handling and stability.
[0132] In summary, all the above embodiments, such as Figure 9 As shown, this application also provides a vehicle steering control method, applied to a vehicle-side control device, the method comprising:
[0133] S501, obtain the vehicle's actual yaw rate, actual lateral acceleration, and actual sideslip angle;
[0134] S502, compare the actual yaw rate with the ideal yaw rate, compare the ideal lateral acceleration with the actual lateral acceleration, and compare the actual center of mass sideslip angle with the first value;
[0135] S503, if the actual yaw rate is less than the ideal yaw rate, the actual lateral acceleration is less than the ideal lateral acceleration, and the actual center of gravity sideslip angle is greater than the first value, then the steering state is determined to be understeering state.
[0136] S504, if the actual yaw rate is greater than the ideal yaw rate, the actual lateral acceleration is greater than the ideal lateral acceleration, and the actual center of gravity sideslip angle is less than the first value, then the steering state is determined to be an oversteering state.
[0137] S505, if the difference between the actual yaw rate and the ideal yaw rate is less than the first deviation threshold, and the difference between the actual lateral acceleration and the ideal lateral acceleration is less than the second deviation threshold, and the difference between the actual center of gravity sideslip angle and the first value is less than the third deviation threshold, then the steering state is determined to be the ideal steering state.
[0138] S506, when the vehicle's steering state is understeering or oversteering, determine whether the vehicle speed is less than a preset speed threshold.
[0139] S507, if the vehicle speed is less than the preset vehicle speed threshold, the target wheel average turning angle is determined based on the ideal lateral acceleration and vehicle speed.
[0140] S508, if the vehicle speed is not less than the preset vehicle speed threshold, the target wheel average turning angle is determined based on the ideal yaw rate and vehicle speed.
[0141] S509, calculate the difference between the target wheel average turning angle and the actual wheel average turning angle to obtain the target turning angle difference;
[0142] S510 adjusts the rack displacement based on the target angle difference and corrects the actual wheel average angle based on the adjusted rack displacement.
[0143] S511, based on the corrected actual wheel average turning angle, control the wheels to turn, and return to execute S501, and, based on the reacquired actual yaw rate, actual lateral acceleration and actual center of gravity sideslip angle, redetermine the vehicle's steering state until the vehicle's steering state is the ideal steering state.
[0144] S512 determines the current angular transmission ratio based on the current vehicle speed, current steering sensitivity, and current yaw rate gain;
[0145] S513, determine the current linear gear ratio based on the current angle-to-angle gear ratio, the actual average wheel rotation angle under ideal steering conditions, and the rack displacement;
[0146] S514 adjusts the current linear angle transmission ratio based on the rack displacement and steering wheel angle under ideal steering conditions.
[0147] It should be noted that the descriptions in S501-S514 above can be found in the relevant descriptions in the above embodiments, and their effects are similar, so they will not be repeated here.
[0148] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages in other steps. It is understood that the steps in different embodiments can be freely combined as needed, and all non-contradictory solutions formed by such combinations are within the scope of protection of this application.
[0149] Based on the same inventive concept, this application also provides a vehicle steering control device for implementing the vehicle steering control method described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations of one or more vehicle steering control device embodiments provided below can be found in the limitations of the vehicle steering control method described above, and will not be repeated here.
[0150] In one exemplary embodiment, such as Figure 10 As shown, a vehicle steering control device is provided, including: a determining module 601, a correcting module 602, and a control module 603, wherein:
[0151] The determination module 601 is used to obtain the actual yaw rate, actual lateral acceleration and actual sideslip angle of the vehicle, and determine the steering state of the vehicle based on the actual yaw rate, actual lateral acceleration and actual sideslip angle.
[0152] The correction module 602 is used to correct the actual wheel average turning angle of the vehicle when the vehicle is in an understeer or oversteer state, based on the vehicle's ideal steering motion parameters, vehicle speed, and rack displacement; the ideal steering motion parameters include ideal yaw rate and / or ideal lateral acceleration.
[0153] The control module 603 is used to control the wheels to steer based on the corrected actual average wheel angle, and to redetermine the vehicle's steering state based on the reacquired actual yaw rate, actual lateral acceleration and actual center of gravity sideslip angle, until the vehicle's steering state is the ideal steering state.
[0154] In one embodiment, the correction module 602 includes:
[0155] The target wheel average steering angle determination unit is used to determine the target wheel average steering angle based on the ideal steering motion parameters and vehicle speed.
[0156] The target steering angle difference determination unit is used to calculate the difference between the target wheel average steering angle and the actual wheel average steering angle to obtain the target steering angle difference.
[0157] The correction unit is used to adjust the rack displacement based on the target angle difference and correct the actual wheel average angle based on the adjusted rack displacement.
[0158] In one embodiment, the target wheel average steering angle determination unit is specifically used for:
[0159] Determine if the vehicle speed is less than the preset vehicle speed threshold;
[0160] If the vehicle speed is less than the preset vehicle speed threshold, the target wheel average turning angle is determined based on the ideal lateral acceleration and vehicle speed.
[0161] If the vehicle speed is not less than the preset vehicle speed threshold, the average turning angle of the target wheel is determined based on the ideal yaw rate and the vehicle speed.
[0162] In one embodiment, the determining module 601 is specifically used for:
[0163] If the actual yaw rate is less than the ideal yaw rate, the actual lateral acceleration is less than the ideal lateral acceleration, and the actual sideslip angle of the center of mass is greater than the first value, then the steering state is determined to be understeering.
[0164] If the actual yaw rate is greater than the ideal yaw rate, the actual lateral acceleration is greater than the ideal lateral acceleration, and the actual sideslip angle is less than the first value, then the steering state is determined to be an oversteering state.
[0165] If the difference between the actual yaw rate and the ideal yaw rate is less than the first deviation threshold, and the difference between the actual lateral acceleration and the ideal lateral acceleration is less than the second deviation threshold, and the difference between the actual center of gravity sideslip angle and the first value is less than the third deviation threshold, then the steering state is determined to be the ideal steering state.
[0166] In one embodiment, the vehicle steering control device further includes:
[0167] The acquisition module is used to obtain the current linear angle transmission ratio and steering wheel angle;
[0168] The adjustment module is used to adjust the current linear angle transmission ratio based on the rack displacement and steering wheel angle under ideal steering conditions.
[0169] In one embodiment, the acquisition module includes:
[0170] The current angle transmission ratio determination unit is used to determine the current angle transmission ratio based on the current vehicle speed, current steering sensitivity, and current yaw rate gain.
[0171] The current line angle transmission ratio determination unit is used to determine the current line angle transmission ratio based on the current line angle transmission ratio, the actual average wheel turning angle under ideal steering conditions, and the rack displacement.
[0172] The various modules in the aforementioned vehicle steering control device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of a computer device as software, so that the processor can call and execute the corresponding operations of each module.
[0173] In one exemplary embodiment, a vehicle-side control device is provided, the internal structure of which can be shown in the following diagram. Figure 11 As shown, the vehicle-mounted control device includes a processor and a memory. The processor provides computational and control capabilities. The memory includes a non-volatile storage medium storing a computer program. When executed by the processor, the computer program implements a vehicle steering control method.
[0174] Those skilled in the art will understand that Figure 11 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer equipment (or vehicle control equipment) to which the present application is applied. The specific computer equipment may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.
[0175] In one exemplary embodiment, a vehicle-mounted control device is provided, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps in the above-described method embodiments.
[0176] In one exemplary embodiment, a vehicle is provided, the vehicle including a vehicle-side control device for performing at least one step in the above method embodiments.
[0177] In one exemplary embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements at least one step in the above method embodiments.
[0178] In one exemplary embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements at least one step in the above method embodiments.
[0179] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program mentioned can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.
[0180] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.
[0181] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.
Claims
1. A vehicle steering control method, characterized in that, The method includes: The vehicle's actual yaw rate, actual lateral acceleration, and actual sideslip angle are obtained, and the vehicle's steering state is determined based on the actual yaw rate, actual lateral acceleration, and actual sideslip angle. When the vehicle is in an understeer or oversteer state, the actual average wheel angle of the vehicle is corrected based on the vehicle's ideal steering motion parameters, vehicle speed, and rack displacement; the ideal steering motion parameters include ideal yaw rate and / or ideal lateral acceleration. Based on the corrected actual average wheel turning angle, the wheels are controlled to steer, and the vehicle's steering state is re-determined based on the re-acquired actual yaw rate, actual lateral acceleration, and actual center of gravity sideslip angle, until the vehicle's steering state is the ideal steering state.
2. The method according to claim 1, characterized in that, The step of correcting the actual average wheel angle of the vehicle based on the vehicle's ideal steering motion parameters, vehicle speed, and rack displacement includes: The target wheel average turning angle is determined based on the ideal steering motion parameters and the vehicle speed. The difference between the target wheel average turning angle and the actual wheel average turning angle is calculated to obtain the target turning angle difference. The rack displacement is adjusted based on the target rotation angle difference, and the actual wheel average rotation angle is corrected based on the adjusted rack displacement.
3. The method according to claim 2, characterized in that, Determining the target wheel's average steering angle based on the ideal steering motion parameters and the vehicle speed includes: Determine whether the vehicle speed is less than a preset vehicle speed threshold; If the vehicle speed is less than the preset vehicle speed threshold, the target wheel average turning angle is determined based on the ideal lateral acceleration and the vehicle speed. If the vehicle speed is not less than the preset vehicle speed threshold, then the target wheel average turning angle is determined based on the ideal yaw rate and the vehicle speed.
4. The method according to any one of claims 1-3, characterized in that, Determining the vehicle's steering state based on the actual yaw rate, the actual lateral acceleration, and the actual sideslip angle includes: If the actual yaw rate is less than the ideal yaw rate, the actual lateral acceleration is less than the ideal lateral acceleration, and the actual center of mass sideslip angle is greater than the first value, then the steering state is determined to be an understeering state. If the actual yaw rate is greater than the ideal yaw rate, the actual lateral acceleration is greater than the ideal lateral acceleration, and the actual center of mass sideslip angle is less than the first value, then the steering state is determined to be an oversteering state. If the difference between the actual yaw rate and the ideal yaw rate is less than a first deviation threshold, and the difference between the actual lateral acceleration and the ideal lateral acceleration is less than a second deviation threshold, and the difference between the actual centroid sideslip angle and the first value is less than a third deviation threshold, then the steering state is determined to be an ideal steering state.
5. The method according to any one of claims 1-3, characterized in that, The method further includes: Get the current gear ratio and steering wheel angle; The current linear angle transmission ratio is adjusted based on the rack displacement and the steering wheel angle under the ideal steering state.
6. The method according to claim 5, characterized in that, The step of obtaining the current linear angle transmission ratio includes: The current angular transmission ratio is determined based on the current vehicle speed, current steering sensitivity, and current yaw rate gain. The current linear angle transmission ratio is determined based on the current angle-to-angle transmission ratio, the actual average wheel turning angle under the ideal steering state, and the rack displacement.
7. A vehicle steering control device, characterized in that, The device includes: The determination module is used to acquire the vehicle's actual yaw rate, actual lateral acceleration, and actual sideslip angle, and to determine the vehicle's steering state based on the actual yaw rate, actual lateral acceleration, and actual sideslip angle. The correction module is used to correct the actual wheel average turning angle of the vehicle based on the vehicle's ideal steering motion parameters, vehicle speed, and rack displacement when the vehicle's steering state is understeer or oversteer; the ideal steering motion parameters include ideal yaw rate and / or ideal lateral acceleration. The control module is used to control the wheels to steer based on the corrected actual average wheel turning angle, and to redetermine the vehicle's steering state based on the reacquired actual yaw rate, actual lateral acceleration, and actual center of gravity sideslip angle, until the vehicle's steering state is the ideal steering state.
8. A vehicle-end control device, comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 6.
9. A vehicle, comprising vehicle-side control equipment, characterized in that, The vehicle-mounted control device is used to perform the steps of the method according to any one of claims 1 to 6.
10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.
11. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 6.