A steering wheel control method, system, and vehicle

Abstract

This application provides a steering wheel control method, system, and vehicle, relating to the field of vehicle control technology. The method includes: firstly, acquiring vehicle path information and vehicle condition information, and calculating the vehicle's path heading angle and rear axle center lateral deviation value based on the path information and vehicle condition information; then, determining the vehicle's heading angle compensation value based on the path heading angle; determining the vehicle's lateral deviation compensation value based on the rear axle center lateral deviation value; compensating the vehicle's steering wheel angle based on the heading angle compensation value and / or lateral deviation compensation value to obtain a compensated steering wheel angle, and filtering the compensated steering wheel angle; finally, controlling the vehicle's steering wheel based on the filtered compensated steering wheel angle. This application reduces steering wheel vibration and improves steering wheel smoothness by first compensating the vehicle's steering wheel angle and then filtering the compensated steering wheel angle.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, and in particular to a steering wheel control method, system, and vehicle. Background Technology

[0002] When a vehicle is in motion, the steering wheel will vibrate significantly when the driving path has a large curvature or changes greatly. This vibration is especially noticeable in complex scenarios such as parking lots where low-speed driving is required.

[0003] Patent CN202111491970.2 employs a fuzzy control algorithm, adjusting the aiming distance based on the vehicle's driving deviation and its rate of change, and then compensating for the baseline aiming distance. This method solves the tracking accuracy problem, but it doesn't adequately address steering wheel vibration. Furthermore, the rate of change of driving deviation often fluctuates significantly during parking maneuvers, easily leading to steering wheel angle vibration.

[0004] Therefore, a new steering wheel control method is urgently needed. Summary of the Invention

[0005] In view of the above problems, embodiments of this application provide a steering wheel control method, system, and vehicle to overcome or at least partially solve the above problems.

[0006] A first aspect of this application provides a steering wheel control method, the method comprising:

[0007] The vehicle's path information and vehicle condition information are obtained, and based on the path information and vehicle condition information, the vehicle's path heading angle and rear axle center lateral deviation value are calculated in the vehicle coordinate system.

[0008] Based on the path heading angle, determine the heading angle compensation value of the vehicle;

[0009] Based on the lateral deviation value of the rear axle center, determine the lateral deviation compensation value of the vehicle;

[0010] The steering wheel angle of the vehicle is compensated according to the heading angle compensation value and / or the lateral deviation compensation value to obtain the compensated steering wheel angle, and the compensated steering wheel angle is filtered by a pre-set filter.

[0011] The steering wheel of the vehicle is controlled based on the compensated steering wheel angle after filtering.

[0012] Optionally, the filter includes a first-order filter and a Butterworth filter, and the filtering process of the compensated steering wheel angle through the pre-set filter includes:

[0013] Based on the vehicle's path information, determine the path curvature of the vehicle's current driving path;

[0014] Determine whether the path curvature is greater than or equal to the first path curvature threshold;

[0015] When the path curvature is greater than or equal to the first path curvature threshold, the compensation steering wheel angle is filtered by the first-order filter.

[0016] If the path curvature is less than the first path curvature threshold, the compensated steering wheel angle is filtered by the Butterworth filter.

[0017] Optionally, compensating the steering wheel angle of the vehicle based on the heading angle compensation value and / or the lateral deviation compensation value includes:

[0018] Based on the vehicle's path information, determine the path curvature of the vehicle's current driving path;

[0019] If the path curvature is greater than a first path curvature threshold and the path heading angle is less than a first preset angle, the steering wheel angle of the vehicle is compensated using the lateral deviation compensation value; or,

[0020] If the path curvature is less than or equal to the first path curvature threshold, and the path heading angle is greater than or equal to the first preset angle, the steering wheel angle of the vehicle is compensated using the heading angle compensation value; or,

[0021] When the path curvature is greater than the first path curvature threshold and the path heading angle is greater than or equal to the first preset angle, the steering wheel angle of the vehicle is compensated by the sum of the lateral deviation compensation value and the heading angle compensation value.

[0022] Optionally, the Butterworth filter is calculated through the following steps:

[0023] Using the mtalab tool, set the passband frequency, cutoff frequency, and filter order of the filter respectively;

[0024] The Butterworth filter is obtained by calculating its transfer function based on the passband frequency, cutoff frequency, and filter order. The Butterworth filter is defined by the following formula:

[0025] [b,a]=butter(buttord(w p ,w s ,r p ,r s ));

[0026] Among them, buttord(w p ,w s ,r p ,r s ) represents the filter order; wp represents the passband frequency; ws represents the cutoff frequency; rp and rs are coefficients.

[0027] Optionally, the first-order filter is shown in the following formula:

[0028] u(n+1)=k filter *u(n)+(1-k filter )*u(n-1)

[0029] Where u is the filter output; n is the period; k filter These are the filter coefficients.

[0030] Optionally, in the vehicle coordinate system, the lateral deviation value of the rear axle center is calculated, including:

[0031] Obtain multiple coordinate points corresponding to the path information in the vehicle coordinate system;

[0032] From the multiple coordinate points corresponding to the path information in the vehicle coordinate system, the coordinate points with a ordinate less than 0 are removed, and the first coordinate point is selected from the remaining coordinate points as the lateral deviation value of the rear axle center of the vehicle. The first coordinate point is the coordinate point closest to the origin of the vehicle coordinate system.

[0033] Optionally, the method further includes:

[0034] Based on the path information and the vehicle condition information, determine the path prediction distance of the vehicle;

[0035] Based on the path prediction distance, a path prediction point matching the path prediction distance is determined in the vehicle coordinate system;

[0036] Based on the path preview point, determine the lateral deviation value of the path preview point;

[0037] The steering wheel angle of the vehicle is determined based on the lateral deviation value of the path preview point.

[0038] Optionally, determining the vehicle's heading angle compensation value based on the path heading angle includes:

[0039] Obtain the target path heading angle of the path preview point in the vehicle coordinate system;

[0040] The heading angle compensation value is calculated using the following formula based on the path heading angle and the target path heading angle:

[0041] HeadingAngle=Kheading*heading match

[0042] Where K is a coefficient, and heading is the path heading angle; heading match The target path heading angle for the path preview point.

[0043] A second aspect of this application provides a steering wheel control system, the system comprising:

[0044] The acquisition module is used to acquire the vehicle's path information and vehicle condition information, and based on the path information and vehicle condition information, calculate the vehicle's path heading angle and rear axle center lateral deviation value in the vehicle coordinate system.

[0045] The first determining module is used to determine the heading angle compensation value of the vehicle based on the path heading angle;

[0046] The second determining module is used to determine the lateral deviation compensation value of the vehicle based on the lateral deviation value of the rear axle center.

[0047] The compensation processing module is used to compensate the steering wheel angle of the vehicle according to the heading angle compensation value and / or the lateral deviation compensation value, to obtain the compensated steering wheel angle, and to filter the compensated steering wheel angle through a pre-set filter.

[0048] The control module is used to control the steering wheel of the vehicle based on the compensated steering wheel angle after filtering.

[0049] Optionally, the filter includes a first-order filter and a Butterworth filter. The filtering process for the compensated steering wheel angle is performed using a pre-set filter. The compensation processing module includes:

[0050] The first determining submodule is used to determine the path curvature of the current driving path of the vehicle based on the vehicle's path information;

[0051] The judgment submodule is used to determine whether the path curvature is greater than or equal to the first path curvature threshold.

[0052] The first filtering submodule is used to filter the compensated steering wheel angle using the first-order filter when the path curvature is greater than or equal to the first path curvature threshold.

[0053] The second filtering submodule is used to filter the compensated steering wheel angle using the Butterworth filter when the path curvature is less than the first path curvature threshold.

[0054] Optionally, the compensation processing module, which compensates the steering wheel angle of the vehicle based on the heading angle compensation value and / or the lateral deviation compensation value, includes:

[0055] The second determining submodule is used to determine the path curvature of the current driving path of the vehicle based on the path information of the vehicle.

[0056] The first compensation submodule is used to compensate the vehicle's steering wheel angle using the lateral deviation compensation value when the path curvature is greater than a first path curvature threshold and the path heading angle is less than a first preset angle; or,

[0057] The second compensation submodule is used to compensate the vehicle's steering wheel angle using the heading angle compensation value when the path curvature is less than or equal to the first path curvature threshold and the path heading angle is greater than or equal to the first preset angle; or,

[0058] The third compensation submodule is used to compensate the steering wheel angle of the vehicle by the sum of the lateral deviation compensation value and the heading angle compensation value when the path curvature is greater than the first path curvature threshold and the path heading angle is greater than or equal to the first preset angle.

[0059] Optionally, the Butterworth filter is calculated through the following steps:

[0060] Using the mtalab tool, set the passband frequency, cutoff frequency, and filter order of the filter respectively;

[0061] The Butterworth filter is obtained by calculating its transfer function based on the passband frequency, cutoff frequency, and filter order. The Butterworth filter is defined by the following formula:

[0062] [b,a]=butter(buttord(w p ,w s ,r p ,r s ));

[0063] Among them, buttord(w p ,w s ,r p ,r s ) represents the filter order; wp represents the passband frequency; ws represents the cutoff frequency; rp and rs are coefficients.

[0064] Optionally, the first-order filter is shown in the following formula:

[0065] u(n+1)=k filter *u(n)+(1-k filter )*u(n-1)

[0066] Where u is the filter output; n is the period; k filter These are the filter coefficients.

[0067] Optionally, in the vehicle coordinate system, the lateral deviation value of the rear axle center of the vehicle is calculated, and the acquisition module includes:

[0068] The first acquisition submodule is used to acquire multiple coordinate points corresponding to the path information in the vehicle coordinate system;

[0069] The selection submodule is used to remove coordinate points with a ordinate less than 0 from multiple coordinate points corresponding to the path information in the vehicle coordinate system, and select the first coordinate point from the remaining coordinate points as the lateral deviation value of the rear axle center of the vehicle. The first coordinate point is the coordinate point closest to the origin of the vehicle coordinate system.

[0070] Optionally, the system further includes:

[0071] The third determining submodule is used to determine the path pre-aiming distance of the vehicle based on the path information and the vehicle condition information;

[0072] The fourth determining submodule is used to determine a path pre-aiming point that matches the path pre-aiming distance in the vehicle coordinate system based on the path pre-aiming distance.

[0073] The fifth determining submodule is used to determine the lateral deviation value of the path pre-aiming point based on the path pre-aiming point;

[0074] The sixth determining submodule is used to determine the steering wheel angle of the vehicle based on the lateral deviation value of the path pre-aiming point.

[0075] Optionally, the first determining module, which determines the heading angle compensation value of the vehicle based on the path heading angle, includes:

[0076] The second acquisition submodule is used to acquire the target path heading angle of the path pre-aiming point in the vehicle coordinate system;

[0077] The calculation submodule is used to calculate the heading angle compensation value based on the path heading angle and the target path heading angle using the following formula:

[0078] HeadingAngle=Kheading*heading match

[0079] Where K is a coefficient, and heading is the path heading angle; heading match The target path heading angle for the path preview point.

[0080] A third aspect of this application provides a vehicle, including:

[0081] One or more processors; and

[0082] One or more machine-readable media storing instructions thereon, when executed by the one or more processors, cause the vehicle to perform the steering wheel control method as described in the first aspect of this application.

[0083] The beneficial effects of this application are:

[0084] This application provides a steering wheel control method, the method comprising: firstly acquiring vehicle path information and vehicle condition information, and based on the path information and vehicle condition information, calculating the vehicle's path heading angle and rear axle center lateral deviation value in the vehicle coordinate system; then determining the vehicle's heading angle compensation value based on the path heading angle; determining the vehicle's lateral deviation compensation value based on the rear axle center lateral deviation value; compensating the vehicle's steering wheel angle based on the heading angle compensation value and / or the lateral deviation compensation value to obtain a compensated steering wheel angle, and filtering the compensated steering wheel angle through a pre-set filter; finally, controlling the vehicle's steering wheel based on the filtered compensated steering wheel angle. This application, during vehicle operation, first compensates the steering wheel angle and then filters the compensated steering wheel angle, thereby reducing steering wheel vibration and improving the smoothness of steering wheel rotation. Attached Figure Description

[0085] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0086] Figure 1 This is a flowchart illustrating the steps of a steering wheel control method provided in an embodiment of this application;

[0087] Figure 2 This is a flowchart of a filtering process for compensating steering wheel angle provided in an embodiment of this application;

[0088] Figure 3 This is a schematic diagram of a pre-aiming control provided in an embodiment of this application;

[0089] Figure 4 This is a schematic diagram of a steering wheel control system provided in an embodiment of this application. Detailed Implementation

[0090] Exemplary embodiments of this application will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of this application are shown in the drawings, it should be understood that this application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of this application and to fully convey the scope of this application to those skilled in the art.

[0091] A first aspect of this application provides a steering wheel control method, the method being as follows: Figure 1 As shown, it includes:

[0092] Step S101: Obtain the vehicle's path information and vehicle condition information, and based on the path information and vehicle condition information, calculate the vehicle's path heading angle and rear axle center lateral deviation value in the vehicle coordinate system.

[0093] Specifically, during vehicle operation, the system obtains the vehicle's path information through cameras and radar (such as lidar, ultrasonic radar, or millimeter-wave radar) installed on the vehicle, and acquires vehicle status information through various types of sensors installed on the vehicle.

[0094] Furthermore, based on the obtained path information and vehicle condition information, the path heading angle and rear axle center lateral deviation value of the vehicle are calculated in the vehicle coordinate system.

[0095] In one optional embodiment, the vehicle coordinate system is a coordinate system established with the rear axle center of the vehicle as the origin. In this embodiment, the path information may include the path coordinates of the vehicle's travel path and the positioning coordinates of the vehicle while traveling on the path. The path is converted into a path in the vehicle coordinate system based on the path coordinates and the positioning coordinates. The conversion formula is as follows:

[0096] Δx=x g -x (1)

[0097] Δy=y g -y (2)

[0098] x v =Δ x cos(heading)-Δ y sin(heading) (3)

[0099] y v =-Δ xsin(heading)+Δy cos(heading) (4)

[0100] Where, x g y g The path coordinates are x and y; the positioning coordinates are x and y; the heading is the positioning heading angle; x v y v These are the vehicle body coordinates.

[0101] Furthermore, based on the vehicle coordinates at two adjacent moments, the path heading angle is calculated using the following formula:

[0102]

[0103] Where heading(i) is the path heading angle.

[0104] In a preferred embodiment, the lateral deviation value of the rear axle center of the vehicle is calculated in the vehicle coordinate system, including:

[0105] Obtain multiple coordinate points corresponding to the path information in the vehicle coordinate system;

[0106] From the multiple coordinate points corresponding to the path information in the vehicle coordinate system, the coordinate points with a ordinate less than 0 are removed, and the first coordinate point is selected from the remaining coordinate points as the lateral deviation value of the rear axle center of the vehicle. The first coordinate point is the coordinate point closest to the origin of the vehicle coordinate system.

[0107] In this embodiment, based on multiple coordinates of the vehicle's driving path in the vehicle coordinate system determined in the above embodiments, coordinate points with a ordinate less than 0 are discarded, and coordinate points with a ordinate greater than or equal to 0 are retained. The first coordinate point closest to the origin of the vehicle coordinate system is determined as the lateral deviation value of the vehicle's rear axle center, denoted as err = -y. v .

[0108] Step S102: Determine the heading angle compensation value of the vehicle based on the path heading angle;

[0109] Specifically, in this step, the heading angle compensation value of the vehicle can be further determined based on the path heading angle obtained in the previous step.

[0110] In a preferred embodiment, a method for determining a heading angle compensation value is provided, specifically including:

[0111] Obtain the target path heading angle of the path preview point in the vehicle coordinate system;

[0112] The heading angle compensation value is calculated based on the path heading angle and the target path heading angle using the following formula (6):

[0113] HeadingAngel=Kheading*heading match (6)

[0114] Where HeadingAngel is the heading angle compensation value; K is the coefficient; heading is the path heading angle; heading match The target path heading angle for the path preview point.

[0115] Step S103: Determine the lateral deviation compensation value of the vehicle based on the lateral deviation value of the rear axle center.

[0116] Specifically, in this step, after determining the lateral deviation value of the rear axle center, the lateral deviation compensation value of the vehicle can be calculated using a PID algorithm.

[0117] First, the lateral deviation value of the rear axle center needs to be integrated according to formula (7), and the specific formula is as follows:

[0118] integrateErr=err*T+integrateErr (7)

[0119] Where, integrateErr is the integral of the rear axle center lateral deviation value; err is the rear axle center lateral deviation value; and T is the coefficient.

[0120] Furthermore, after obtaining the integral of the lateral deviation value of the rear axle center, the lateral deviation compensation value of the vehicle is calculated using the following formula (8):

[0121] pidAngle=Kp*err+Ki*integrateErr (8)

[0122] Where pidAngle is the lateral deviation compensation value, K p K i All are coefficients, and integralErr is the integral of the lateral deviation value of the rear axle center.

[0123] Step S104: Based on the heading angle compensation value and / or the lateral deviation compensation value, the steering wheel angle of the vehicle is compensated to obtain the compensated steering wheel angle, and the compensated steering wheel angle is filtered by a pre-set filter.

[0124] Specifically, in this step, the vehicle's steering wheel angle is compensated based on the heading angle compensation value and / or lateral deviation compensation value. In practical applications, the heading angle compensation value can be used to compensate for the difference between the vehicle's current heading and the target heading, while the lateral deviation compensation value can be used to compensate for the deviation from the center line of the vehicle's current lane. Using these compensation values, a compensated steering wheel angle is calculated, enabling the vehicle to travel better along the predetermined path, thereby significantly reducing steering wheel vibration.

[0125] Furthermore, the calculated compensated steering wheel angle is filtered. The filter smooths changes in steering wheel angle, reduces vibration and instability, and improves vehicle stability. In practical applications, the preset filter parameters can be adjusted according to actual testing and requirements to achieve the best filtering effect.

[0126] In summary, the purpose of step S104 is to ensure that the vehicle can travel stably and accurately along the predetermined path by compensating and filtering the steering wheel angle, reducing steering wheel vibration and smoothing changes in steering wheel angle, thereby enhancing the reliability and comfort of vehicle control.

[0127] Step S105: Based on the compensated steering wheel angle after filtering, control the steering wheel of the vehicle.

[0128] Specifically, in this step, the vehicle's control system can control the vehicle's steering wheel based on the filtered and compensated steering wheel angle, enabling the vehicle to pass through the current driving path more smoothly.

[0129] This application first compensates for the steering wheel angle during vehicle operation, and then filters the compensated steering wheel angle to reduce steering wheel vibration and improve the smoothness of steering wheel rotation.

[0130] In a preferred embodiment, the filter includes a first-order filter and a Butterworth filter, and the filtering process of the compensated steering wheel angle through the pre-set filter includes:

[0131] Based on the vehicle's path information, determine the path curvature of the vehicle's current driving path;

[0132] Determine whether the path curvature is greater than or equal to the first path curvature threshold;

[0133] When the path curvature is greater than or equal to the first path curvature threshold, the compensation steering wheel angle is filtered by the first-order filter.

[0134] If the path curvature is less than the first path curvature threshold, the compensated steering wheel angle is filtered by the Butterworth filter.

[0135] Specifically, such as Figure 2 As shown, in this embodiment, the filter includes a first-order filter and a Butterworth filter. The filtering process of the compensated steering wheel angle through the pre-set filter includes the following steps:

[0136] First, based on the vehicle's path information, determine the path curvature of the vehicle's current driving route. Path curvature refers to the degree of curvature of the vehicle's current driving route, which reflects the complexity and changing trend of the vehicle's driving path. Based on the magnitude of the path curvature, it can be determined whether the vehicle is in a relatively complex or sharp turning driving environment.

[0137] Next, it is determined whether the path curvature is greater than or equal to the first path curvature threshold. The first path curvature threshold is a pre-set standard used to distinguish the magnitude of path curvature, thereby determining which filter to use for filtering.

[0138] When the path curvature is greater than or equal to the first path curvature threshold, a first-order filter is used to filter the compensated steering wheel angle. A first-order filter is a relatively simple filter suitable for handling rapidly changing signals. When the path curvature is large, the vehicle may need to quickly adjust the steering wheel angle; the first-order filter provides a faster response to meet the needs of sharp turns.

[0139] When the path curvature is less than the first path curvature threshold, a Butterworth filter is used to filter the compensated steering wheel angle. The Butterworth filter has a smooth frequency response, effectively filtering out high-frequency noise and providing a relatively stable filtering effect. When the path curvature is small, the vehicle's driving path is relatively flat; using a Butterworth filter can make the steering wheel angle change smoother, reducing steering wheel vibration and thus improving vehicle comfort and stability.

[0140] This filtering method allows for the selection of appropriate filters to compensate for steering wheel angles based on the vehicle's current driving path, ensuring smooth and precise vehicle operation on both complex and smooth roads. This approach not only improves the response speed and accuracy of the vehicle control system but also enhances the overall driving experience.

[0141] In a preferred embodiment, the Butterworth filter is calculated through the following steps:

[0142] Using the mtalab tool, set the passband frequency, cutoff frequency, and filter order of the filter respectively;

[0143] The Butterworth filter is obtained by calculating the transfer function based on the passband frequency, cutoff frequency, and filter order. The Butterworth filter is defined by the following formula (9):

[0144] [b,a]=butter(buttord(w p ,w s ,r p ,r s (9)

[0145] Among them, buttord(w p ,w s ,r p ,r s ) represents the filter order; wp represents the passband frequency; ws represents the cutoff frequency; rp and rs are coefficients.

[0146] Among them, passband frequency

[0147] Cutoff frequency

[0148] Among them, F s =1500; the peak of the passband frequency does not exceed r p dB:r p =0.6; the attenuation of the cutoff frequency is not less than r s dB:r s =1.8.

[0149] In a preferred embodiment, the first-order filter is shown in the following formula (10):

[0150] u(n+1)=k filter *u(n)+(1-k filter )*u(n-1) (10)

[0151] Where u is the filter output; n is the period; k filter This is the filter coefficient, which is usually set to 0.2.

[0152] In a preferred embodiment, compensating the steering wheel angle of the vehicle based on the heading angle compensation value and / or the lateral deviation compensation value includes:

[0153] Based on the vehicle's path information, determine the path curvature of the vehicle's current driving path;

[0154] If the path curvature is greater than a first path curvature threshold and the path heading angle is less than a first preset angle, the steering wheel angle of the vehicle is compensated using the lateral deviation compensation value; or,

[0155] If the path curvature is less than or equal to the first path curvature threshold, and the path heading angle is greater than or equal to the first preset angle, the steering wheel angle of the vehicle is compensated using the heading angle compensation value; or,

[0156] When the path curvature is greater than the first path curvature threshold and the path heading angle is greater than or equal to the first preset angle, the steering wheel angle of the vehicle is compensated by the sum of the lateral deviation compensation value and the heading angle compensation value.

[0157] Specifically, in this embodiment, compensating the steering wheel angle of the vehicle based on the heading angle compensation value and / or the lateral deviation compensation value includes the following steps:

[0158] First, based on the vehicle's path information, the path curvature of the vehicle's current driving path is determined. Path curvature refers to the degree of curvature of the vehicle's current driving route, reflecting the complexity of the path. Path information can be obtained through sensors or a navigation system, and this data is crucial for subsequent steering wheel angle compensation.

[0159] When the path curvature is greater than a first path curvature threshold and the path heading angle is less than a first preset angle, the vehicle's steering wheel angle is compensated using the lateral deviation compensation value. This typically occurs in scenarios where the path curvature is significant and the vehicle needs to quickly adjust its direction. The lateral deviation compensation value is based on the vehicle's offset relative to the lane center, enabling rapid correction of the vehicle's position and ensuring safe driving within the lane.

[0160] When the path curvature is less than or equal to the first path curvature threshold and the path heading angle is greater than or equal to the first preset angle, the steering wheel angle of the vehicle is compensated using the heading angle compensation value. When the path is relatively straight and the vehicle's driving direction is relatively consistent with the target direction, the heading angle compensation value can effectively adjust the vehicle's direction, keeping it on the correct driving trajectory and reducing unnecessary deviations.

[0161] When the path curvature is greater than the first path curvature threshold and the path heading angle is greater than or equal to the first preset angle, the vehicle's steering wheel angle is compensated using the sum of the lateral deviation compensation value and the heading angle compensation value. This situation typically occurs when the vehicle is driving on complex curves, requiring consideration of both the path curvature and the vehicle's heading. By simultaneously using the lateral deviation compensation value and the heading angle compensation value, the steering wheel angle can be adjusted more precisely, ensuring the vehicle can smoothly navigate complex road sections.

[0162] Through the above steps, lateral deviation compensation and heading angle compensation values ​​can be flexibly applied according to different driving path conditions to accurately compensate for the steering wheel angle, thereby improving the vehicle's driving stability and safety under various road conditions. This comprehensive compensation method can adapt to changing driving environments, providing more intelligent and reliable vehicle control and enhancing the user's driving experience.

[0163] In a preferred embodiment, a method for calculating the steering wheel angle is provided, specifically including:

[0164] Based on the path information and the vehicle condition information, determine the path prediction distance of the vehicle;

[0165] Based on the path prediction distance, a path prediction point matching the path prediction distance is determined in the vehicle coordinate system;

[0166] Based on the path preview point, determine the lateral deviation value of the path preview point;

[0167] The steering wheel angle of the vehicle is determined based on the lateral deviation value of the path preview point.

[0168] Specifically, in this embodiment, reference is made to... Figure 3 The diagram illustrates a pre-aiming control method. First, based on the path information and vehicle condition information, the pre-aiming distance for the vehicle is determined. The path information includes the geometry and curvature of the vehicle's current driving path, while the vehicle condition information includes dynamic parameters such as speed and acceleration. The pre-aiming distance is a key parameter, representing the length of the path ahead that the driving system needs to consider in advance for accurate directional control. Generally, the faster the vehicle speed, the longer the pre-aiming distance, ensuring that the vehicle can travel smoothly and safely along the path.

[0169] For example, this embodiment provides a formula (11) for calculating the path preview distance:

[0170] LoodAhed=2.5+2v x -30curve (11)

[0171] Where LoodAhed is the aiming distance; v x is the vehicle speed; curve is the path curvature.

[0172] Furthermore, based on the predicted path distance, a path prediction point matching this distance is determined in the vehicle coordinate system. The vehicle coordinate system is a coordinate system centered on the vehicle, used to describe the relationship between the vehicle's surrounding environment and the driving path. The path prediction point is the specific location the vehicle is expected to traverse at the predicted distance. When determining the path prediction point, the curvature of the current path and the vehicle's dynamic parameters need to be considered to ensure the accuracy of the prediction point. In this embodiment, the path prediction point is denoted as x. match y match ,heading match .

[0173] Further, based on the path preview point, the lateral deviation value of the preview point is determined and denoted as Lat_err = 0 - y. match Lateral deviation refers to the lateral offset of the path preview point relative to the lane center or ideal driving path. This value reflects the degree to which the vehicle deviates from the ideal path and is an important basis for subsequent steering wheel angle adjustments. The larger the lateral deviation value, the more severe the vehicle's deviation from the path, requiring greater steering adjustments.

[0174] Furthermore, the steering wheel angle of the vehicle is determined based on the lateral deviation value of the path pre-aiming point. In practical applications, the determination of the steering wheel angle is usually based on a certain control algorithm, such as a proportional-integral-derivative (PID) control algorithm, which can calculate the required steering wheel angle based on the lateral deviation value to correct the vehicle's driving direction and make it travel along the predetermined path. By continuously adjusting the steering wheel angle, it is ensured that the vehicle can smoothly and safely follow the ideal driving path.

[0175] For example, in this embodiment, the steering wheel angle of the vehicle is calculated using the following formulas (12) and (13):

[0176]

[0177] steerAngle=15.4*tireAngle*180 / π (13)

[0178] Where tireAngle is the wheel angle; steerAngle is the steering wheel angle; WheelBase is the wheelbase; and 15.4 is the steering gear ratio.

[0179] In this embodiment, the vehicle's steering wheel angle can be precisely controlled based on path and vehicle condition information, thereby improving the vehicle's driving stability and safety under various road conditions. This method not only adapts to complex and ever-changing driving environments but also provides a more intelligent and reliable vehicle control system.

[0180] This application provides a steering wheel control method, the method comprising: firstly acquiring vehicle path information and vehicle condition information, and based on the path information and vehicle condition information, calculating the vehicle's path heading angle and rear axle center lateral deviation value in the vehicle coordinate system; then determining the vehicle's heading angle compensation value based on the path heading angle; determining the vehicle's lateral deviation compensation value based on the rear axle center lateral deviation value; compensating the vehicle's steering wheel angle based on the heading angle compensation value and / or the lateral deviation compensation value to obtain a compensated steering wheel angle, and filtering the compensated steering wheel angle through a pre-set filter; finally, controlling the vehicle's steering wheel based on the filtered compensated steering wheel angle. This application, during vehicle operation, first compensates the steering wheel angle and then filters the compensated steering wheel angle, thereby reducing steering wheel vibration and improving the smoothness of steering wheel rotation.

[0181] Based on the same inventive concept, a second aspect of the embodiments of this application provides a steering wheel control system, such as... Figure 4 As shown, the system includes:

[0182] The acquisition module 201 is used to acquire the vehicle's path information and vehicle condition information, and based on the path information and vehicle condition information, calculate the vehicle's path heading angle and rear axle center lateral deviation value in the vehicle coordinate system.

[0183] The first determining module 202 is used to determine the heading angle compensation value of the vehicle based on the path heading angle;

[0184] The second determining module 203 is used to determine the lateral deviation compensation value of the vehicle based on the lateral deviation value of the rear axle center.

[0185] The compensation processing module 204 is used to compensate the steering wheel angle of the vehicle according to the heading angle compensation value and / or the lateral deviation compensation value, to obtain the compensated steering wheel angle, and to filter the compensated steering wheel angle through a preset filter.

[0186] The control module 205 is used to control the steering wheel of the vehicle based on the compensated steering wheel angle after filtering.

[0187] Optionally, the filter includes a first-order filter and a Butterworth filter. The compensation processing module 204, which filters the steering wheel angle using a pre-set filter, includes:

[0188] The first determining submodule is used to determine the path curvature of the current driving path of the vehicle based on the vehicle's path information;

[0189] The judgment submodule is used to determine whether the path curvature is greater than or equal to the first path curvature threshold.

[0190] The first filtering submodule is used to filter the compensated steering wheel angle using the first-order filter when the path curvature is greater than or equal to the first path curvature threshold.

[0191] The second filtering submodule is used to filter the compensated steering wheel angle using the Butterworth filter when the path curvature is less than the first path curvature threshold.

[0192] Optionally, the compensation processing module 204, which compensates the steering wheel angle of the vehicle based on the heading angle compensation value and / or the lateral deviation compensation value, includes:

[0193] The second determining submodule is used to determine the path curvature of the current driving path of the vehicle based on the path information of the vehicle.

[0194] The first compensation submodule is used to compensate the vehicle's steering wheel angle using the lateral deviation compensation value when the path curvature is greater than a first path curvature threshold and the path heading angle is less than a first preset angle; or,

[0195] The second compensation submodule is used to compensate the vehicle's steering wheel angle using the heading angle compensation value when the path curvature is less than or equal to the first path curvature threshold and the path heading angle is greater than or equal to the first preset angle; or,

[0196] The third compensation submodule is used to compensate the steering wheel angle of the vehicle by the sum of the lateral deviation compensation value and the heading angle compensation value when the path curvature is greater than the first path curvature threshold and the path heading angle is greater than or equal to the first preset angle.

[0197] Optionally, the Butterworth filter is calculated through the following steps:

[0198] Using the mtalab tool, set the passband frequency, cutoff frequency, and filter order of the filter respectively;

[0199] The Butterworth filter is obtained by calculating its transfer function based on the passband frequency, cutoff frequency, and filter order. The Butterworth filter is defined by the following formula:

[0200] [b,a]=butter(buttord(w p ,w s rp ,r s ));

[0201] Among them, buttord(w p ,w s ,r p ,r s ) represents the filter order; wp represents the passband frequency; ws represents the cutoff frequency; rp and rs are coefficients.

[0202] Optionally, the first-order filter is shown in the following formula:

[0203] u(n+1)=k filter *u(n)+(1-k filter )*u(n-1)

[0204] Where u is the filter output; n is the period; k filter These are the filter coefficients.

[0205] Optionally, in the vehicle coordinate system, the lateral deviation value of the rear axle center of the vehicle is calculated. The acquisition module 201 includes:

[0206] The first acquisition submodule is used to acquire multiple coordinate points corresponding to the path information in the vehicle coordinate system;

[0207] The selection submodule is used to remove coordinate points with a ordinate less than 0 from multiple coordinate points corresponding to the path information in the vehicle coordinate system, and select the first coordinate point from the remaining coordinate points as the lateral deviation value of the rear axle center of the vehicle. The first coordinate point is the coordinate point closest to the origin of the vehicle coordinate system.

[0208] Optionally, the system further includes:

[0209] The third determining submodule is used to determine the path pre-aiming distance of the vehicle based on the path information and the vehicle condition information;

[0210] The fourth determining submodule is used to determine a path pre-aiming point that matches the path pre-aiming distance in the vehicle coordinate system based on the path pre-aiming distance.

[0211] The fifth determining submodule is used to determine the lateral deviation value of the path pre-aiming point based on the path pre-aiming point;

[0212] The sixth determining submodule is used to determine the steering wheel angle of the vehicle based on the lateral deviation value of the path pre-aiming point.

[0213] Optionally, the first determining module, which determines the heading angle compensation value of the vehicle based on the path heading angle, includes:

[0214] The second acquisition submodule is used to acquire the target path heading angle of the path pre-aiming point in the vehicle coordinate system;

[0215] The calculation submodule is used to calculate the heading angle compensation value based on the path heading angle and the target path heading angle using the following formula:

[0216] HeadingAngle=Kheading*heading match

[0217] Where K is a coefficient, and heading is the path heading angle; heading match The target path heading angle for the path preview point.

[0218] Based on the same inventive concept, a third aspect of the embodiments of this application provides a vehicle, including:

[0219] One or more processors; and

[0220] One or more machine-readable media storing instructions thereon, when executed by the one or more processors, cause the vehicle to perform the steering wheel control method as described in the first aspect of this application.

[0221] Each embodiment in this specification focuses on the differences from other embodiments. For the same or similar parts between the embodiments, please refer to each other.

[0222] Those skilled in the art will understand that embodiments of this application can be provided as methods, apparatus, or computer program products. Therefore, embodiments of this application can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, embodiments of this application can take the form of computer program products implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0223] This application describes embodiments with reference to flowchart illustrations and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1A device that provides the functions specified in one or more boxes.

[0224] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0225] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, causing a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0226] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

[0227] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0228] The above provides a detailed description of the steering wheel control method, system, and vehicle. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A steering wheel control method, characterized in that, The method includes: The vehicle's path information and vehicle condition information are obtained, and based on the path information and vehicle condition information, the vehicle's path heading angle and rear axle center lateral deviation value are calculated in the vehicle coordinate system. Based on the path heading angle, determine the heading angle compensation value of the vehicle; Based on the lateral deviation value of the rear axle center, determine the lateral deviation compensation value of the vehicle; The steering wheel angle of the vehicle is compensated according to the heading angle compensation value and / or the lateral deviation compensation value to obtain the compensated steering wheel angle, and the compensated steering wheel angle is filtered by a pre-set filter. The steering wheel of the vehicle is controlled based on the compensated steering wheel angle after filtering. The filter includes a first-order filter and a Butterworth filter. The filtering process of the compensated steering wheel angle using a pre-set filter includes: Based on the vehicle's path information, determine the path curvature of the vehicle's current driving path; Determine whether the path curvature is greater than or equal to the first path curvature threshold; When the path curvature is greater than or equal to the first path curvature threshold, the compensation steering wheel angle is filtered by the first-order filter. If the path curvature is less than the first path curvature threshold, the compensated steering wheel angle is filtered by the Butterworth filter.

2. The steering wheel control method according to claim 1, characterized in that, The step of compensating the steering wheel angle of the vehicle based on the heading angle compensation value and / or the lateral deviation compensation value includes: Based on the vehicle's path information, determine the path curvature of the vehicle's current driving path; If the path curvature is greater than a first path curvature threshold and the path heading angle is less than a first preset angle, the steering wheel angle of the vehicle is compensated using the lateral deviation compensation value; or, If the path curvature is less than or equal to the first path curvature threshold, and the path heading angle is greater than or equal to the first preset angle, the steering wheel angle of the vehicle is compensated using the heading angle compensation value; or, When the path curvature is greater than the first path curvature threshold and the path heading angle is greater than or equal to the first preset angle, the steering wheel angle of the vehicle is compensated by the sum of the lateral deviation compensation value and the heading angle compensation value.

3. The steering wheel control method according to claim 1, characterized in that, The Butterworth filter is calculated through the following steps: Using the mtalab tool, set the passband frequency, cutoff frequency, and filter order of the filter respectively; The Butterworth filter is obtained by calculating its transfer function based on the passband frequency, cutoff frequency, and filter order. The Butterworth filter is defined by the following formula: ； in, is the filter order; wp is the passband frequency; ws is the cutoff frequency; rp and rs are coefficients.

4. The steering wheel control method according to claim 1, characterized in that, The first-order filter is shown in the following formula: Where u is the filter output; n is the period; These are the filter coefficients.

5. A steering wheel control method according to claim 1, characterized in that, In the vehicle coordinate system, the lateral deviation value of the rear axle center of the vehicle is calculated, including: Obtain multiple coordinate points corresponding to the path information in the vehicle coordinate system; From the multiple coordinate points corresponding to the path information in the vehicle coordinate system, the coordinate points with a ordinate less than 0 are removed, and the first coordinate point is selected from the remaining coordinate points as the lateral deviation value of the rear axle center of the vehicle. The first coordinate point is the coordinate point closest to the origin of the vehicle coordinate system.

6. The steering wheel control method according to claim 1, characterized in that, The method further includes: Based on the path information and the vehicle condition information, determine the path prediction distance of the vehicle; Based on the path prediction distance, a path prediction point matching the path prediction distance is determined in the vehicle coordinate system; Based on the path preview point, determine the lateral deviation value of the path preview point; The steering wheel angle of the vehicle is determined based on the lateral deviation value of the path preview point.

7. A steering wheel control method according to claim 6, characterized in that, Determining the heading angle compensation value of the vehicle based on the path heading angle includes: Obtain the target path heading angle of the path preview point in the vehicle coordinate system; The heading angle compensation value is calculated using the following formula based on the path heading angle and the target path heading angle: Where K is a coefficient, The path heading angle; The target path heading angle for the path preview point.

8. A steering wheel control system, characterized in that, The system includes: The acquisition module is used to acquire the vehicle's path information and vehicle condition information, and based on the path information and vehicle condition information, calculate the vehicle's path heading angle and rear axle center lateral deviation value in the vehicle coordinate system. The first determining module is used to determine the heading angle compensation value of the vehicle based on the path heading angle; The second determining module is used to determine the lateral deviation compensation value of the vehicle based on the lateral deviation value of the rear axle center. The compensation processing module is used to compensate the steering wheel angle of the vehicle according to the heading angle compensation value and / or the lateral deviation compensation value, to obtain the compensated steering wheel angle, and to filter the compensated steering wheel angle through a pre-set filter. The control module is used to control the steering wheel of the vehicle based on the compensated steering wheel angle after filtering. The filter includes a first-order filter and a Butterworth filter. The filter is used to filter the compensated steering wheel angle using a pre-set filter. The compensation processing module includes: The first determining submodule is used to determine the path curvature of the current driving path of the vehicle based on the vehicle's path information; The judgment submodule is used to determine whether the path curvature is greater than or equal to the first path curvature threshold. The first filtering submodule is used to filter the compensated steering wheel angle using the first-order filter when the path curvature is greater than or equal to the first path curvature threshold. The second filtering submodule is used to filter the compensated steering wheel angle using the Butterworth filter when the path curvature is less than the first path curvature threshold.

9. A vehicle, characterized in that, include: One or more processors; and One or more machine-readable media having instructions stored thereon, which, when executed by the one or more processors, cause the vehicle to perform the steering wheel control method as described in any one of claims 1-7.

Images