Vehicle control method, device, apparatus, and storage medium

Abstract

The application discloses a vehicle control method, device, equipment and storage medium, relates to the steering control technical field, and discloses a vehicle control method, which comprises the following steps: acquiring an initial position, a running angle and a target position of a vehicle, and controlling the vehicle to run according to the initial position and the running angle; obtaining a wheel speed pulse change amount of the vehicle when the vehicle runs to the target position; calculating an Ackermann offset according to the wheel speed pulse change amount, and controlling the vehicle according to the Ackermann offset. The Ackermann offset can be determined by calculating the wheel speed pulse change amount according to the initial position, the running angle and the target position of the vehicle, so that the vehicle can be accurately controlled to run to the target position.

Description

Technical Field

[0001] This application relates to the field of steering control technology, and more particularly to vehicle control methods, devices, equipment and storage media. Background Technology

[0002] In current vehicle dynamics control and autonomous driving assistance systems, precise steering control is a key requirement for achieving smooth and safe vehicle operation. To achieve precise steering control, the vehicle needs to accurately calculate the steering angle of each wheel during steering to avoid understeer or oversteer, while reducing tire slippage and wear, ensuring the vehicle stays on a predetermined trajectory in low-speed autonomous driving and parking scenarios. The Ackermann offset is the offset between the ideal geometric center and the actual center of motion of the vehicle during steering; achieving precise steering control places high demands on the accuracy of the Ackermann offset calibration.

[0003] However, existing Ackerman offset calibration methods have certain limitations. Traditional calibration methods are cumbersome, difficult to guarantee accuracy, and in sharp turns or complex road conditions, vehicle dynamics, such as roll, tire lateral forces, and center of gravity shift, can affect the actual driving path, causing deviations between the ideal and actual paths. This results in insufficient steering control accuracy under complex conditions, making it difficult to meet the high-precision, automated steering control requirements of autonomous driving and advanced driver assistance systems.

[0004] The above content is only used to help understand the technical solution of this application and does not represent an admission that the above content is prior art. Summary of the Invention

[0005] The main purpose of this application is to provide a vehicle control method, device, equipment and storage medium, which aims to solve the technical problems of the cumbersome and low-accuracy calibration process of traditional Ackerman offset calibration.

[0006] To achieve the above objectives, this application proposes a vehicle control method, the method comprising:

[0007] The vehicle's initial position, driving angle, and target position are obtained, and the vehicle's movement is controlled based on the initial position and the driving angle.

[0008] When the vehicle reaches the target position, the change in the vehicle's wheel speed pulse is obtained;

[0009] The Ackerman offset is calculated based on the wheel speed pulse change, and the vehicle is controlled based on the Ackerman offset.

[0010] In one embodiment, the step of calculating the Ackerman offset based on the wheel speed pulse change includes:

[0011] Obtain the vehicle wheelbase;

[0012] Calculate the front wheel turning radius and the rear wheel turning radius based on the wheel speed pulse change;

[0013] The Ackerman offset is calculated based on the front wheel turning radius, the rear wheel turning radius, and the vehicle wheelbase.

[0014] In one embodiment, the step of calculating the front wheel turning radius and the rear wheel turning radius based on the wheel speed pulse change includes:

[0015] The changes in front wheel speed pulses, rear wheel speed pulses, and wheel travel distance are obtained based on the wheel speed pulse changes.

[0016] The front wheel turning radius is calculated based on the change in front wheel speed pulse and the distance traveled by the wheels.

[0017] The rear wheel turning radius is calculated based on the change in rear wheel speed pulses and the distance traveled by the wheels.

[0018] In one embodiment, the step of obtaining the initial position, driving angle, and target position of the vehicle, and controlling the vehicle's driving based on the initial position and the driving angle, includes:

[0019] Obtain the vehicle's initial position;

[0020] The vehicle is connected to the controller local area network (CLAN), and a driving command is sent to the CLAN so that the CLAN can determine the vehicle's driving angle based on the driving command.

[0021] The vehicle is controlled to travel based on the initial position and the travel angle.

[0022] In one embodiment, after the step of calculating the Ackerman offset based on the wheel speed pulse change, the method further includes:

[0023] The vehicle's speed, steering wheel angle, vehicle mass, center of gravity height, and suspension stiffness are obtained.

[0024] The center of gravity offset is calculated based on the driving speed, the steering wheel angle, the vehicle mass, the center of gravity height, and the suspension stiffness.

[0025] The Ackerman offset is corrected based on the stated center of gravity offset.

[0026] In one embodiment, the step of calculating the center of gravity offset based on the driving speed, the steering wheel angle, the vehicle mass, the center of gravity height, and the suspension stiffness includes:

[0027] The tire lateral stiffness of the vehicle is obtained, and the tire lateral angle is obtained based on the driving speed and the steering wheel angle.

[0028] Calculate the roll angle based on the tire lateral stiffness and the slip angle;

[0029] The center of gravity offset is calculated based on the tilt angle.

[0030] In one embodiment, the step of calculating the roll angle based on the tire lateral stiffness and the slip angle includes:

[0031] Calculate the tire lateral force based on the slip angle and the tire slip stiffness;

[0032] The roll angle is calculated based on the vehicle mass, the center of gravity height, the suspension stiffness, and the tire lateral force.

[0033] In addition, to achieve the above objectives, this application also proposes a vehicle control device, which includes: a driving module for acquiring the initial position, driving angle and target position of the vehicle, and controlling the vehicle to drive according to the initial position and the driving angle;

[0034] The module obtains the wheel speed pulse change of the vehicle when the vehicle travels to the target position;

[0035] The calculation module calculates the Ackerman offset based on the wheel speed pulse change.

[0036] In addition, to achieve the above objectives, this application also proposes a vehicle control device, the device comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the vehicle control method as described above.

[0037] In addition, to achieve the above objectives, this application also proposes a storage medium, which is a computer-readable storage medium, on which a computer program is stored, and which, when executed by a processor, implements the steps of the vehicle control method described above.

[0038] In addition, to achieve the above objectives, this application also provides a computer program product, which includes a computer program that, when executed by a processor, implements the steps of the vehicle control method described above.

[0039] One or more technical solutions proposed in this application have at least the following technical effects:

[0040] By employing techniques that acquire the vehicle's initial position, driving angle, and target position, and control the vehicle's movement based on the initial position and driving angle; obtaining the wheel speed pulse change when the vehicle reaches the target position; calculating the Ackerman offset based on the wheel speed pulse change; and controlling the vehicle based on the Ackerman offset, this approach solves the problems of complex operation, difficult alignment, and low measurement accuracy in traditional Ackerman offset calibration. Compared with existing perpendicularity measurement methods, it significantly reduces manual operation steps, improves calibration accuracy and efficiency, and achieves high automation and accuracy assurance in the calibration process. Attached Figure Description

[0041] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0042] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a flowchart illustrating an embodiment of the vehicle control method of this application.

[0044] Figure 2 This is a flowchart illustrating Embodiment 2 of the vehicle control method of this application;

[0045] Figure 3 This is a geometrical diagram of the vehicle turning path of the vehicle control method provided in Embodiment 2 of this application;

[0046] Figure 4 This is a flowchart illustrating Embodiment 3 of the vehicle control method of this application;

[0047] Figure 5 This is a schematic diagram of the module structure of the vehicle control device according to an embodiment of this application;

[0048] Figure 6 This is a schematic diagram of the equipment structure of the hardware operating environment involved in the vehicle control method in the embodiments of this application.

[0049] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0050] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.

[0051] To better understand the technical solution of this application, a detailed description will be provided below in conjunction with the accompanying drawings and specific implementation methods.

[0052] The main solution of this application embodiment is: to obtain the initial position, driving angle and target position of the vehicle, and to control the vehicle to drive according to the initial position and the driving angle;

[0053] When the vehicle reaches the target position, the change in the vehicle's wheel speed pulse is obtained;

[0054] The Ackerman offset is calculated based on the wheel speed pulse change, and the vehicle is controlled based on the Ackerman offset.

[0055] In this embodiment, for ease of description, the following description will focus on the vehicle control device as the executing entity.

[0056] Because existing traditional Ackerman offset calibration processes are cumbersome and lack high accuracy, this application provides a solution. This solution involves acquiring the vehicle's initial position, driving angle, and target position, and controlling the vehicle's movement based on the initial position and driving angle. When the vehicle reaches the target position, the wheel speed pulse change is obtained. The Ackerman offset is calculated based on the wheel speed pulse change, and the vehicle is controlled based on the Ackerman offset. This solution effectively solves the problems of complex operation, difficult alignment, and low measurement accuracy in traditional Ackerman offset calibration. Compared with existing perpendicularity measurement methods, it significantly reduces manual operation steps, improves calibration accuracy and efficiency, and achieves high automation and accuracy assurance in the calibration process.

[0057] It should be noted that the executing entity in this embodiment can be a computing service device with data processing, network communication, and program execution functions, such as a tablet computer, personal computer, or mobile phone, or an electronic device or vehicle control device capable of performing the above functions. The following description uses a vehicle control device as an example to illustrate this embodiment and the subsequent embodiments.

[0058] Based on this, embodiments of this application provide a vehicle control method, referring to... Figure 1 , Figure 1 This is a flowchart illustrating the first embodiment of the vehicle control method of this application.

[0059] In this embodiment, the vehicle control device method includes steps S10 to S30:

[0060] Step S10: Obtain the initial position, driving angle and target position of the vehicle, and control the vehicle to drive based on the initial position and driving angle.

[0061] It should be noted that the initial position mentioned above can be the specific position of the vehicle at the start of the calibration process, and this position will serve as the starting point for the vehicle's subsequent travel. The initial position can be determined by a positioning system, such as GPS or a positioning device installed on the vehicle, or by using manual marking methods to determine the vehicle's position through physical markers. The purpose of positioning is to record where the vehicle starts traveling for subsequent calibration and offset calculations; the specific method of obtaining this information is not limited in this embodiment. The driving angle mentioned above can refer to the vehicle's direction of travel relative to the initial position. The driving angle reflects the vehicle's steering state and trajectory. The target position mentioned above can be a predetermined position that the vehicle plans to reach, typically a target point pre-set to complete the calibration process.

[0062] Understandably, controlling a vehicle to move from its initial position to its target position requires maintaining a constant steering wheel angle while driving at a low, constant speed to ensure that the vehicle does not slip or be affected by other uncontrollable factors.

[0063] For example, Ackerman offset calibration is performed in an open test track. The vehicle's initial position is a specific marker point on the track, determined manually or via GPS. The steering wheel angle is fixed at a specific value via a CAN bus device, such as a 30-degree left turn. The target position is the vehicle returning to its initial position or a designated endpoint after traversing an arc. Throughout the journey, the steering wheel angle remains constant via the CAN bus as the vehicle travels at a constant speed from its initial position, traversing a circle of known radius. When the vehicle reaches the target position, it stops and marks the location for the next offset calculation. This process ensures precise control of each parameter during the vehicle's trajectory, thereby guaranteeing the reliability and accuracy of the calibration results.

[0064] Step S20: When the vehicle reaches the target position, the change in the vehicle's wheel speed pulse is obtained.

[0065] It should be noted that the aforementioned wheel speed pulse change refers to the total number of pulse signal changes collected by the vehicle's wheel speed sensors, typically located on the wheels, during vehicle operation. These pulse signals reflect the number of wheel rotations and the distance traveled. The wheel speed sensor determines the vehicle's travel distance by recording the pulse signals emitted when the wheel rotates a certain angle. Each pulse represents a specific distance the wheel has traveled, therefore the accumulated pulse count can be used to calculate the total distance traveled. Obtaining the wheel speed pulse change at the end point of the Ackerman offset calibration process is for subsequent calculation of the vehicle's actual travel distance and further calibration of the Ackerman offset.

[0066] Understandably, wheel speed pulse signals can be acquired by connecting a CAN bus device to the vehicle's control system to collect pulse signals emitted by the vehicle's wheel speed sensors. During vehicle operation, the wheel speed sensors send pulse signals to the CAN bus, and the CAN bus device transmits these signals to the host computer software, recording the pulse changes throughout the entire driving process. When the vehicle reaches the target position, the host computer software records the total number of pulse signals at this point and compares it with the number of pulses at the initial position, thus obtaining the change in wheel speed pulses throughout the entire driving process.

[0067] For example, the initial position is marked as point A, and the target position is the vehicle returning to point A after completing one lap of a circular trajectory with a fixed radius. During the vehicle's movement, wheel speed sensors on the wheels continuously generate pulse signals, which are transmitted to the host computer via the CAN bus. Assume each pulse represents a certain angle of wheel rotation, such as 5 degrees. When the vehicle reaches the target position, i.e., completes one full circle, the host computer software records 500 wheel speed pulse changes. This means the vehicle's wheels have rotated 500 times by 5 degrees, which can be used to calculate the total distance traveled.

[0068] Step S30: Calculate the Ackerman offset based on the wheel speed pulse change, and control the vehicle based on the Ackerman offset.

[0069] It's important to note that the Ackerman offset mentioned above reflects the vehicle's steering characteristics during cornering. A smaller offset means the vehicle is more likely to follow the ideal Ackerman geometry path, thus reducing tire slippage and understeer. After obtaining the Ackerman offset, it can be used as an input parameter to adjust the vehicle's steering control strategy. For example, a large Ackerman offset indicates that the vehicle's steering angle is not ideal, potentially causing understeer or oversteer. In this case, it's necessary to adjust the steering wheel angle or vehicle speed to ensure the vehicle follows the ideal path.

[0070] Understandably, the offset can be calculated by combining the travel distance of the front and rear wheels with the vehicle's geometry, such as wheelbase and the position of the front and rear wheels.

[0071] In one feasible implementation, step S10 may include steps S11 to S13:

[0072] Step S11: Obtain the initial position of the vehicle.

[0073] Step S12: Connect the vehicle to the controller local area network and send a driving command to the controller local area network so that the controller local area network can determine the driving angle of the vehicle based on the driving command.

[0074] Step S13: Control the vehicle's movement based on the initial position and driving angle.

[0075] It is understandable that steps S11 to S13 above represent the vehicle starting from its initial position, connecting to the CAN bus device, and using CAN signals to control the steering wheel to remain fixed at a certain angle. For example, starting from point A, the vehicle is controlled to move according to the pre-defined driving angle, such as a 30-degree left turn. The CAN bus connection allows the host computer to continuously receive data such as wheel speed pulse signals and steering wheel angle, and control the vehicle's throttle and steering wheel angle to ensure that the vehicle smoothly travels along the predetermined direction to the target position. Through low-speed, uniform speed control, the vehicle can accurately complete detours or turns, ensuring the accuracy of data acquisition.

[0076] It should be noted that the aforementioned Controller Area Network (CAN) is a network system used for in-vehicle communication. It connects multiple control units within the vehicle, enabling real-time data transmission and control signal delivery. In this step, the vehicle is physically connected to the CAN to allow the controller to communicate and transmit commands to the various control units within the vehicle. Once connected to the CAN, various sensor data from the vehicle, such as steering wheel angle, vehicle speed, and wheel speed pulses, can be collected and transmitted in real-time to the central control system for subsequent calculations and control.

[0077] This embodiment provides a vehicle control method that solves the technical problems of traditional Ackerman offset calibration methods, such as cumbersome operation, high difficulty, and difficulty in guaranteeing calibration accuracy, by using a vehicle positioning system to obtain the initial position and CAN bus equipment to control the steering wheel angle and throttle to maintain the vehicle's low-speed constant speed. This achieves the beneficial effects of simplifying operation steps, improving calibration accuracy, and realizing a higher degree of automation. By precisely controlling the vehicle to travel from the initial position to the target position and collecting wheel speed pulse changes during the journey, the Ackerman offset is calculated based on the vehicle's geometric characteristics. This optimizes the vehicle's steering control strategy, ensuring the vehicle travels along the ideal path, reducing tire slippage and understeer, and improving vehicle handling and safety. Simultaneously, the two steps of ensuring the vehicle is perpendicular to the baseline in the original process are eliminated. Calibration personnel only need to mark the vehicle's starting position, lightly press the accelerator, and control the vehicle to circle once before stopping at the starting position. This reduces the operation steps and time in the calibration process, simplifying the operation.

[0078] Based on the first embodiment of this application, in the second embodiment of this application, the content that is the same as or similar to that in the first embodiment described above can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 2 Step S30 of the vehicle control method includes steps S31 to S33:

[0079] Step S31: Obtain the vehicle wheelbase.

[0080] It should be noted that the vehicle wheelbase mentioned above refers to the horizontal distance between the front and rear axles, usually measured in meters or millimeters. It is one of the important parameters describing a vehicle's geometric characteristics and has a direct impact on its handling, stability, and steering performance.

[0081] Step S32: Calculate the turning radius of the front wheel and the turning radius of the rear wheel based on the wheel speed pulse change.

[0082] It should be noted that the front wheel turning radius and rear wheel turning radius mentioned above refer to the turning radii of the front and rear wheels, respectively. These two values ​​are used to describe the actual driving trajectory of the front and rear wheels during the vehicle's maneuvering. Generally, the turning radius of the front wheels is larger than that of the rear wheels because the front wheels guide the vehicle's steering, while the rear wheels follow the path of the front wheels.

[0083] Please refer to Figure 3 , Figure 3 This is a geometrical diagram of the vehicle turning path in the first embodiment of the vehicle control method of this application.

[0084] like Figure 3 As shown, R is the turning radius of the front wheel, r is the turning radius of the rear wheel, L is the wheelbase of the vehicle, i.e. the distance between the front and rear wheels, a is the Ackerman offset, O represents the turning center of the vehicle, and θ is the angle between the turning radius of the front wheel and the wheelbase of the vehicle.

[0085] Understandably, by Figure 3 The geometric relationship for angle θ can be expressed as Equation 1:

[0086]

[0087] In the formula, L is the vehicle wheelbase, a is the Ackerman offset, and R is the turning radius of the front wheels.

[0088] From geometric relations and the law of cosines, we can obtain the following equation 2:

[0089]

[0090] In the formula, L is the vehicle wheelbase, a is the Ackerman offset, R is the turning radius of the front wheels, and r is the turning radius of the rear wheels.

[0091] In one feasible implementation, step S32 may include steps S321 to S323:

[0092] From equations 1 and 2 above, we can obtain equation 3 below:

[0093]

[0094] In the formula, L is the vehicle wheelbase, a is the Ackerman offset, R is the turning radius of the front wheels, and r is the turning radius of the rear wheels.

[0095] Step S321: Obtain the front wheel speed pulse change, the rear wheel speed pulse change, and the wheel travel distance based on the wheel speed pulse change.

[0096] It should be noted that during the calibration process, the wheel speed pulse changes of the front and rear wheels are acquired independently because their travel trajectories and distances during vehicle cornering are typically different. By independently recording the wheel speed pulses, the front and rear wheel speed pulse changes can be obtained. These changes represent the number of rotations of the front and rear wheels during the entire driving process, i.e., the distance traveled by the front and rear wheels, respectively.

[0097] Additionally, it should be noted that the wheel travel distance mentioned above refers to the actual path length traversed by the wheels during vehicle operation. Since the front and rear wheels travel along the same predetermined trajectory during calibration, their travel distances are the same. This distance is determined based on the wheel speed pulse changes recorded by the wheel speed sensors and is used for subsequent Ackerman offset calculations.

[0098] Step S322: Calculate the front wheel turning radius based on the change in front wheel speed pulse and the distance traveled by the wheels.

[0099] Understandably, by using the change in wheel speed pulses of the front wheels and the known distance traveled by the wheels, the turning radius of the front wheels, i.e., the radius of the arc trajectory of the front wheels during vehicle turning, can be derived. The turning radius of the front wheels is calculated as follows: Equation 4:

[0100]

[0101] In the formula, n f denoted as the pulse change in front wheel speed, k as the distance traveled by the wheel, and R as the turning radius of the front wheel.

[0102] Step S323: Calculate the rear wheel turning radius based on the change in rear wheel speed pulse and the distance traveled by the wheel.

[0103] Understandably, the turning radius of the rear wheels can be calculated using the change in wheel speed pulses and the distance traveled by the wheels. This radius represents the radius of the arc path traveled by the rear wheels when turning. The calculation of the rear wheel turning radius is shown in Equation 5:

[0104]

[0105] In the formula, n r denoted as the change in rear wheel speed pulse, k is the distance traveled by the wheel, and r is the turning radius of the rear wheel.

[0106] Step S33: Calculate the Ackerman offset based on the front wheel turning radius, the rear wheel turning radius, and the vehicle wheelbase.

[0107] Understandably, the Ackermann offset is derived by combining the calculated front wheel turning radius, rear wheel turning radius, and vehicle wheelbase. Combining equations 3, 4, and 5 above, the calculation of the Ackermann offset is shown in equation 6 below:

[0108]

[0109] In the formula, L is the vehicle wheelbase, a is the Ackerman offset, R is the turning radius of the front wheels, r is the turning radius of the rear wheels, k is the wheel travel distance, and n f n represents the change in front wheel speed pulse. r This represents the pulse change in rear wheel speed.

[0110] This embodiment provides a vehicle control method that solves the technical problem of accurately measuring and calculating the Ackerman offset of a vehicle in traditional methods by acquiring the vehicle's wheelbase and calculating the turning radii of the front and rear wheels using wheel speed pulse changes. This achieves the beneficial effects of improving the calibration accuracy of the Ackerman offset, simplifying the measurement process, and reducing human error, thereby optimizing the vehicle's steering control performance and improving vehicle handling and driving safety. Calibration personnel do not need to perform any measurements throughout the process; the data emitted by the sensors is collected via the CAN bus and sent to the host computer software, where the calibration results can be directly calculated, achieving a higher degree of automation. Through precise geometric relationships and mathematical model calculations, this embodiment can more accurately reflect the steering characteristics of the vehicle in actual driving, providing important parameter support for the tuning and optimization of the vehicle steering system.

[0111] Based on the first embodiment of this application, in the third embodiment of this application, the content that is the same as or similar to that in the first embodiment described above can be referred to the above description, and will not be repeated hereafter. Based on this, please refer to... Figure 4 After step S30, the vehicle control method further includes steps S40 to S60:

[0112] Step S40: Obtain the vehicle's driving speed, steering wheel angle, vehicle mass, center of gravity height, and suspension stiffness.

[0113] It should be noted that the aforementioned driving speed can be the real-time speed of the vehicle during calibration, and this speed is an important parameter affecting the vehicle's turning radius and steering characteristics. The aforementioned steering wheel angle can describe the rotation angle of the steering wheel set by the driver's input or the automatic control system command. This angle directly affects the front wheel steering angle, thus affecting the vehicle's turning path. The aforementioned vehicle mass can be the overall mass of the vehicle, including unloaded mass and load. Vehicle mass has a significant impact on the vehicle's steering characteristics and roll characteristics. The aforementioned center of gravity height can refer to the vertical height of the vehicle's center of gravity relative to the ground. Center of gravity height affects the vehicle's roll characteristics, that is, the vehicle's stability and degree of roll during cornering. The aforementioned suspension stiffness describes the elastic characteristics of the vehicle's suspension system, that is, the suspension system's ability to resist compression. Suspension stiffness has a direct impact on the vehicle's roll angle and vehicle stability during cornering.

[0114] Step S50: Calculate the center of gravity offset based on driving speed, steering wheel angle, vehicle mass, center of gravity height, and suspension stiffness.

[0115] It should be noted that the aforementioned center of gravity offset can be the lateral displacement of the vehicle's center of gravity relative to its stationary position caused by lateral forces, roll, and other factors during cornering. This offset is an important parameter for analyzing the vehicle's steering stability and handling characteristics, and it affects the vehicle's dynamic performance during cornering.

[0116] Understandably, higher speeds result in greater lateral acceleration, directly increasing lateral forces and thus affecting the degree of center of gravity shift. The steering wheel angle determines the curvature and radius of the vehicle's turn, thus influencing the magnitude of lateral forces during cornering. A larger vehicle mass generates greater inertial forces during cornering, increasing center of gravity shift. A higher center of gravity height leads to more pronounced roll during cornering, exacerbating the shift. A high center of gravity makes the vehicle more prone to roll under lateral forces. Suspension stiffness describes the suspension system's ability to resist compression; a stiffer suspension results in less roll and center of gravity shift during cornering, while a softer suspension makes the vehicle more susceptible to significant center of gravity shift.

[0117] In one feasible implementation, step S50 may include steps S51 to S53:

[0118] Step S51: Obtain the tire lateral stiffness of the vehicle and obtain the tire lateral angle based on the driving speed and steering wheel angle.

[0119] It should be noted that the tire lateral stiffness mentioned above can be the magnitude of the lateral force generated per unit slip angle when the tire is subjected to lateral force. It describes the tire's ability to respond to lateral deformation and is an important parameter for evaluating the lateral force generated by the tire during steering.

[0120] As we can understand it, the slip angle is the angle between the actual direction of the tire's travel and its direction of travel relative to the vehicle's body. During vehicle cornering, the deformation of the tire causes the wheel to not travel entirely in the direction of steering, but rather to exhibit a certain degree of "slippage," thus creating the slip angle. The tire's slip angle can be derived from the vehicle's speed and steering wheel angle; the faster the speed and the larger the steering wheel angle, the greater the slip angle will be.

[0121] Step S52: Calculate the roll angle based on the tire lateral stiffness and roll angle.

[0122] It should be noted that the roll angle mentioned above refers to the angle of inclination of the vehicle body relative to the horizontal plane during cornering, due to the effects of lateral acceleration and tire lateral forces. The roll angle reflects the lateral dynamic performance of the vehicle during cornering and affects the vehicle's stability.

[0123] In one feasible implementation, step S52 may include steps S521 to S522:

[0124] Step S521: Calculate the tire lateral force based on the slip angle and tire lateral stiffness.

[0125] It should be noted that the aforementioned tire lateral force can be the force generated by the tire due to the slip angle, used to overcome lateral slippage during cornering, allowing the vehicle to travel along the intended cornering trajectory. The greater the tire lateral force, the more stable the vehicle is during cornering. The tire lateral force is calculated as follows: Equation 7:

[0126] F y =C α ×α (Equation 7)

[0127] In the formula, C α Let α be the tire's lateral stiffness, and α be the tire's slip angle, which can be derived from the vehicle speed and steering wheel angle.

[0128] Step S522: Calculate the roll angle based on the vehicle mass, center of gravity height, suspension stiffness, and tire lateral force.

[0129] Understandably, by combining vehicle mass, center of gravity height, and suspension stiffness, the roll angle during cornering can be calculated. The roll angle is calculated using the following formula: 8.

[0130]

[0131] In the formula, K roll F represents the roll stiffness of the vehicle suspension. y Let be the lateral force of the tire, and m and h be the mass and center of gravity of the vehicle, respectively.

[0132] Step S53: Calculate the center of gravity offset based on the roll angle.

[0133] It should be noted that the aforementioned center of gravity offset refers to the lateral movement of the vehicle's center of gravity when the vehicle rolls. The center of gravity offset is derived from the roll angle and represents the lateral displacement of the center of gravity caused by the vehicle's roll during cornering. The center of gravity offset is calculated as shown in Equation 9:

[0134]

[0135] In the formula, h is the height of the center of gravity, and the angle is... This is the roll angle.

[0136] Step S60: Correct the Ackerman offset based on the center of gravity offset.

[0137] Understandably, the Ackerman offset describes the degree of deviation between the ideal geometric trajectory and the actual trajectory of a vehicle during steering. Due to the influence of center of gravity shift, the vehicle's steering trajectory will change, therefore the original Ackerman offset needs to be corrected to reflect the changes caused by the center of gravity shift. The correction of the Ackerman offset is shown in Equation 10 below:

[0138] a′=a+k×Δy (Formula 10)

[0139] In the formula, a′ is the corrected Ackerman offset, a is the original Ackerman offset, Δy is the center of gravity offset caused by roll, and k is an adjustment coefficient used to adapt to the characteristics of different vehicles.

[0140] This embodiment provides a vehicle control method that uses real-time acquisition of vehicle speed, steering wheel angle, vehicle mass, center of gravity height, and suspension stiffness, combined with these parameters, to calculate the center of gravity offset. This solves the problem of inaccurate Ackerman offset calculation due to factors such as body roll during vehicle steering, which affects vehicle steering stability and handling. By introducing a correction for the center of gravity offset, this embodiment can more accurately reflect the vehicle's steering characteristics in actual driving, achieving the beneficial effects of improving the accuracy of Ackerman offset calibration, optimizing vehicle steering control strategies, and enhancing vehicle driving safety and stability. Furthermore, it considers tire lateral stiffness and suspension system characteristics, further refining the vehicle dynamics model and providing more comprehensive data support for the analysis and improvement of vehicle dynamic performance.

[0141] It should be noted that the above examples are only for understanding this application and do not constitute a limitation on the vehicle control method of this application. Any simple modifications based on this technical concept are within the protection scope of this application.

[0142] This application also provides a vehicle control device, please refer to... Figure 5The vehicle control device includes:

[0143] The driving module 10 is used to acquire the initial position, driving angle and target position of the vehicle, and control the vehicle to drive according to the initial position and the driving angle;

[0144] The module 20 obtains the wheel speed pulse change of the vehicle when the vehicle travels to the target position;

[0145] The calculation module 30 calculates the Ackerman offset based on the wheel speed pulse change.

[0146] The vehicle control device provided in this application, employing the vehicle control method described in the above embodiments, can solve the technical problems of cumbersome and low-accuracy calibration processes in traditional Ackerman offset calibration. Compared with the prior art, the beneficial effects of the vehicle control device provided in this application are the same as those of the vehicle control method provided in the above embodiments, and other technical features in the vehicle control device are the same as those disclosed in the methods of the above embodiments, and will not be repeated here.

[0147] In one embodiment, the calculation module 30 is further configured to obtain the vehicle wheelbase; calculate the front wheel turning radius and the rear wheel turning radius based on the wheel speed pulse change; and calculate the Ackerman offset based on the front wheel turning radius, the rear wheel turning radius, and the vehicle wheelbase.

[0148] In one embodiment, the calculation module 30 is further configured to obtain the front wheel speed pulse change, the rear wheel speed pulse change, and the wheel travel distance based on the wheel speed pulse change; calculate the front wheel turning radius based on the front wheel speed pulse change and the wheel travel distance; and calculate the rear wheel turning radius based on the rear wheel speed pulse change and the wheel travel distance.

[0149] In one embodiment, the driving module 10 is further configured to obtain the initial position of the vehicle; connect the vehicle to a controller local area network (CLAN) and send a driving command to the CLAN, so that the CLAN calibrates the driving angle of the vehicle based on the driving command; and control the vehicle to drive according to the initial position and the driving angle.

[0150] In one embodiment, the calculation module 30 is further configured to acquire the vehicle's driving speed, steering wheel angle, vehicle mass, center of gravity height, and suspension stiffness; calculate the center of gravity offset based on the driving speed, steering wheel angle, vehicle mass, center of gravity height, and suspension stiffness; and correct the Ackermann offset based on the center of gravity offset.

[0151] In one embodiment, the calculation module 30 is further configured to obtain the tire lateral stiffness of the vehicle, obtain the tire slip angle based on the driving speed and the steering wheel angle, calculate the roll angle based on the tire lateral stiffness and the slip angle, and calculate the center of gravity offset based on the roll angle.

[0152] In one embodiment, the calculation module 30 is further configured to calculate the tire lateral force based on the slip angle and the tire lateral stiffness; and to calculate the roll angle based on the vehicle mass, the center of gravity height, the suspension stiffness, and the tire lateral force.

[0153] This application provides a vehicle control device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, which are executed by the at least one processor to enable the at least one processor to perform the vehicle control method in Embodiment 1 above.

[0154] The following is for reference. Figure 6 The diagram illustrates a structural schematic suitable for implementing vehicle control devices according to embodiments of this application. Vehicle control devices in embodiments of this application may include, but are not limited to, mobile terminals such as mobile phones, laptops, digital radio receivers, PDAs (Personal Digital Assistants), PADs (Portable Application Description), PMPs (Portable Media Players), in-vehicle terminals (e.g., in-vehicle navigation terminals), and fixed terminals such as digital TVs and desktop computers. Figure 6 The vehicle control device shown is merely an example and should not be construed as limiting the functionality and scope of use of the embodiments of this application.

[0155] like Figure 6As shown, the vehicle control device may include a processing unit 1001 (e.g., a central processing unit, a graphics processing unit, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 1002 or a program loaded from a storage device 1003 into a random access memory (RAM) 1004. The RAM 1004 also stores various programs and data required for the operation of the vehicle control device. The processing unit 1001, ROM 1002, and RAM 1004 are interconnected via a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Typically, the following systems can be connected to the I / O interface 1006: input devices 1007 including, for example, a touchscreen, touchpad, keyboard, mouse, image sensor, microphone, accelerometer, gyroscope, etc.; output devices 1008 including, for example, a liquid crystal display (LCD), speaker, vibrator, etc.; storage devices 1003 including, for example, magnetic tape, hard disk, etc.; and communication devices 1009. The communication device 1009 allows the vehicle control equipment to communicate wirelessly or wiredly with other devices to exchange data. Although the figures show vehicle control equipment with various systems, it should be understood that it is not required to implement or have all of the systems shown. More or fewer systems may be implemented alternatively.

[0156] Specifically, according to the embodiments disclosed in this application, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments disclosed in this application include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device, or installed from storage device 1003, or installed from ROM 1002. When the computer program is executed by processing device 1001, it performs the functions defined in the methods of the embodiments disclosed in this application.

[0157] The vehicle control device provided in this application, employing the vehicle control method described in the above embodiments, can solve the technical problems of cumbersome and low-accuracy calibration processes in traditional Ackerman offset calibration. Compared with the prior art, the beneficial effects of the vehicle control device provided in this application are the same as those of the vehicle control method provided in the above embodiments, and other technical features of this vehicle control device are the same as those disclosed in the previous embodiment method, and will not be repeated here.

[0158] It should be understood that the various parts disclosed in this application can be implemented using hardware, software, firmware, or a combination thereof. In the description of the above embodiments, specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples.

[0159] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0160] This application provides a computer-readable storage medium having computer-readable program instructions (i.e., a computer program) stored thereon, the computer-readable program instructions being used to execute the vehicle control method in the above embodiments.

[0161] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, system, or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0162] The aforementioned computer-readable storage medium may be included in the vehicle control equipment; or it may exist independently and not be installed in the vehicle control equipment.

[0163] The aforementioned computer-readable storage medium carries one or more programs that, when executed by the vehicle control device, cause the vehicle control device to control the vehicle.

[0164] Computer program code for performing the operations of this application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a Local Area Network (LAN) or a Wide Area Network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0165] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0166] The modules described in the embodiments of this application can be implemented in software or hardware. The names of the modules do not necessarily limit the functionality of the unit itself.

[0167] The readable storage medium provided in this application is a computer-readable storage medium that stores computer-readable program instructions (i.e., a computer program) for executing the above-described vehicle control method. This solves the technical problems of cumbersome and inaccurate traditional Ackerman offset calibration processes. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in this application are the same as those of the vehicle control method provided in the above embodiments, and will not be elaborated upon here.

[0168] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the vehicle control method described above.

[0169] The computer program product provided in this application can solve the technical problems of cumbersome and low-accuracy calibration processes in traditional Ackerman offset calibration. Compared with the prior art, the beneficial effects of the computer program product provided in this application are the same as those of the vehicle control method provided in the above embodiments, and will not be repeated here.

[0170] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.

Claims

1. A vehicle control method, characterized in that, The method includes: The vehicle's initial position, driving angle, and target position are obtained, and the vehicle's movement is controlled based on the initial position and the driving angle. When the vehicle reaches the target position, the change in the vehicle's wheel speed pulse is obtained; The Ackerman offset is calculated based on the wheel speed pulse change, and the vehicle is controlled based on the Ackerman offset. The step of calculating the Ackerman offset based on the wheel speed pulse change includes: Obtain the vehicle wheelbase; The changes in front wheel speed pulses, rear wheel speed pulses, and wheel travel distance are obtained based on the wheel speed pulse changes. The front wheel turning radius is calculated based on the change in front wheel speed pulse and the distance traveled by the wheels. The rear wheel turning radius is calculated based on the rear wheel speed pulse change and the wheel travel distance. The Ackermann offset is calculated based on the front wheel turning radius, the rear wheel turning radius, and the vehicle wheelbase. After the step of calculating the Ackerman offset based on the wheel speed pulse change, the method further includes: The vehicle's speed, steering wheel angle, vehicle mass, center of gravity height, and suspension stiffness are obtained. The center of gravity offset is calculated based on the driving speed, the steering wheel angle, the vehicle mass, the center of gravity height, and the suspension stiffness. The Ackerman offset is corrected based on the stated center of gravity offset.

2. The method as described in claim 1, characterized in that, The step of obtaining the vehicle's initial position, driving angle, and target position, and controlling the vehicle's movement based on the initial position and the driving angle, includes: Obtain the vehicle's initial position; The vehicle is connected to the controller local area network (CLAN), and a driving command is sent to the CLAN so that the CLAN can determine the vehicle's driving angle based on the driving command. The vehicle is controlled to travel based on the initial position and the travel angle.

3. The method as described in claim 1, characterized in that, The step of calculating the center of gravity offset based on the driving speed, the steering wheel angle, the vehicle mass, the center of gravity height, and the suspension stiffness includes: The tire lateral stiffness of the vehicle is obtained, and the tire lateral angle is obtained based on the driving speed and the steering wheel angle. Calculate the roll angle based on the tire lateral stiffness and the slip angle; The center of gravity offset is calculated based on the tilt angle.

4. The method as described in claim 3, characterized in that, The step of calculating the roll angle based on the tire lateral stiffness and the lateral angle includes: Calculate the tire lateral force based on the slip angle and the tire slip stiffness; The roll angle is calculated based on the vehicle mass, the center of gravity height, the suspension stiffness, and the tire lateral force.

5. A vehicle control device, characterized in that, The device includes: The driving module is used to acquire the initial position, driving angle and target position of the vehicle, and control the vehicle to drive according to the initial position and the driving angle; The module obtains the wheel speed pulse change of the vehicle when the vehicle travels to the target position; The calculation module calculates the Ackerman offset based on the wheel speed pulse change. The calculation module is also used to obtain the vehicle wheelbase; obtain the front wheel speed pulse change, the rear wheel speed pulse change, and the wheel travel distance based on the wheel speed pulse change; calculate the front wheel turning radius based on the front wheel speed pulse change and the wheel travel distance; calculate the rear wheel turning radius based on the rear wheel speed pulse change and the wheel travel distance; and calculate the Ackerman offset based on the front wheel turning radius, the rear wheel turning radius, and the vehicle wheelbase. The calculation module is also used to obtain the vehicle's driving speed, steering wheel angle, vehicle mass, center of gravity height, and suspension stiffness; calculate the center of gravity offset based on the driving speed, steering wheel angle, vehicle mass, center of gravity height, and suspension stiffness; and correct the Ackermann offset based on the center of gravity offset.

6. A vehicle control device, characterized in that, The device includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, the computer program being configured to implement the steps of the vehicle control method as described in any one of claims 1 to 4.

7. A storage medium, characterized in that, The storage medium is a computer-readable storage medium, and a computer program is stored on the storage medium. When the computer program is executed by a processor, it implements the steps of the vehicle control method as described in any one of claims 1 to 4.

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