Method and device for determining steering rack force and vehicle

Abstract

The invention discloses a steering rack force determining method and device and a vehicle, and belongs to the field of vehicle control. The method comprises the steps of obtaining vehicle parameters of a vehicle; determining a first friction torque, a second friction torque, a first aligning torque and a second aligning torque of the vehicle by using the vehicle parameters; determining a rotation resistance torque based on the first friction torque, the second friction torque, the first aligning torque and the second aligning torque; first and second pull rod forces are determined using the rotational resistance torque and vehicle parameters, and a steering rack force of the vehicle is determined based on the first and second pull rod forces. According to the method, the two wheels are decoupled, the friction torque and the aligning torque of the two wheels are used for determining the rotation resistance torque, the asymmetry of stress of the two wheels in the vehicle steering process is considered, and the accuracy of determining the rotation resistance torque is improved. On the basis, the first pull rod force and the second pull rod force are calculated through the rotation resistance moment, the steering rack force is obtained, and the accuracy of determining the steering rack force is improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of vehicle control, and in particular to a method and device for determining steering rack force, and a vehicle. Background Art

[0002] In the automotive industry, the vehicle steering system affects vehicle control and driving safety. As a key parameter in the vehicle steering system, steering rack force directly influences the selection, design, and performance optimization of the vehicle steering system.

[0003] In the related art, the determination of steering rack force is mainly based on theoretical models and empirical formulas, and is generally applied to simple suspension structures (such as McPherson suspension structure and double A-arm suspension structure). However, with the continuous development of vehicles, suspension structures are becoming more and more complex. For example, there are double wishbone suspension structures with virtual kingpins and high-order double wishbone suspension structures. When the steering rack force of complex suspension structures is determined by theoretical models and empirical formulas, there is a large deviation between the determined steering rack force and the actual result, which reduces the accuracy of the determined steering rack force and leads to a decrease in the accuracy of the steering system selection based on the steering rack force, thereby reducing vehicle safety performance or increasing vehicle costs. Summary of the Invention

[0004] This application provides a method, device, and vehicle for determining steering rack force, which can improve the accuracy of the determined steering rack force. The technical solution is as follows:

[0005] In one aspect, an embodiment of the present application provides a method for determining a steering rack force, the method comprising:

[0006] Get vehicle parameters of the vehicle;

[0007] Determining a first friction torque, a second friction torque, a first aligning torque, and a second aligning torque of the vehicle using the vehicle parameters;

[0008] determining a rotational resistance torque based on the first friction torque, the second friction torque, the first aligning torque, and the second aligning torque;

[0009] A first tie rod force and a second tie rod force are determined using the rotational resistance torque and the vehicle parameters, and a steering rack force of the vehicle is determined based on the first tie rod force and the second tie rod force.

[0010] On the other hand, an embodiment of the present application provides a device for determining a steering rack force, the device comprising:

[0011] An acquisition module, used to obtain vehicle parameters of the vehicle;

[0012] a determination module, configured to determine a first friction torque, a second friction torque, a first aligning torque, and a second aligning torque of the vehicle using the vehicle parameters;

[0013] The determining module is further configured to determine a rotational resistance torque based on the first friction torque, the second friction torque, the first aligning torque, and the second aligning torque;

[0014] The determination module is further configured to determine a first tie rod force and a second tie rod force using the rotational resistance torque and the vehicle parameters, and determine a steering rack force of the vehicle based on the first tie rod force and the second tie rod force.

[0015] In one possible implementation, the vehicle parameters include a front axle full load, a tire-ground friction coefficient, a tire footprint length, a tire footprint width, and a first kingpin offset. The determination module is configured to determine a first tire kingpin-associated parameter using the tire footprint length, the tire footprint width, and the first kingpin offset; and to determine a first friction torque of the vehicle using the front axle full load, the tire-ground friction coefficient, and the first tire kingpin-associated parameter.

[0016] In one possible implementation, the vehicle parameters include a front axle full load, a tire-ground friction coefficient, a tire footprint length, a tire footprint width, and a second kingpin offset. The determination module is configured to determine a second tire kingpin-associated parameter using the tire footprint length, the tire footprint width, and the second kingpin offset; and to determine a second friction torque of the vehicle using the front axle full load, the tire-ground friction coefficient, and the second tire kingpin-associated parameter.

[0017] In one possible implementation, the vehicle parameters include a front axle full load, a first kingpin inclination angle, a first maximum turning angle, a second maximum turning angle, a first kingpin caster angle, a first kingpin offset, and a tire rolling radius, and the determination module is used to determine a turning angle parameter based on the first maximum turning angle and the second maximum turning angle; determine a first lever arm coefficient based on the first kingpin offset, the first kingpin inclination angle, and the tire rolling radius; and determine the first restoring torque using the front axle full load, the first kingpin inclination angle, the turning angle parameter, the first kingpin caster angle, and the first lever arm coefficient.

[0018] In one possible implementation, the vehicle parameters include a front axle full load, a second kingpin inclination angle, a first maximum turning angle, a second maximum turning angle, a second kingpin caster angle, a second kingpin offset, and a tire rolling radius, and the determination module is used to determine a turning angle parameter based on the first maximum turning angle and the second maximum turning angle; determine a second lever arm coefficient based on the second kingpin offset, the second kingpin inclination angle, and the tire rolling radius; and determine the second restoring torque using the front axle full load, the second kingpin inclination angle, the turning angle parameter, the second kingpin caster angle, and the second lever arm coefficient.

[0019] In one possible implementation, the vehicle parameters also include a first lever arm and a second lever arm, and the determination module is used to determine the first tie rod force using the rotational resistance torque and the first lever arm, and to determine the second tie rod force using the rotational resistance torque and the second lever arm, wherein the first lever arm is the lever arm from the first tie rod of the vehicle to the kingpin axis, and the second lever arm is the lever arm from the second tie rod of the vehicle to the kingpin axis.

[0020] In one possible implementation, the vehicle parameters also include a first angle and a second angle, and the determination module is used to determine a first steering rack force based on the first tie rod force and the first angle, where the first angle is the angle between the first tie rod and the rack of the vehicle; determine a second steering rack force based on the second tie rod force and the second angle, where the second angle is the angle between the second tie rod and the rack of the vehicle; and determine the steering rack force of the vehicle using the first steering rack force and the second steering rack force.

[0021] In a possible implementation, the vehicle parameters further include tire material data and tire pressure data, and the acquisition module is further configured to acquire environmental parameters of the vehicle, where the environmental parameters include at least one of ground roughness, temperature, or humidity;

[0022] The determination module is further used to determine a static friction coefficient or a dynamic friction coefficient using the tire material data, the tire pressure data and the environmental parameters, the static friction coefficient representing the friction coefficient between the tire and the ground when the vehicle is stationary, and the dynamic friction coefficient representing the friction coefficient between the tire and the ground when the vehicle is in a moving state; the friction coefficient between the tire and the ground is determined based on the static friction coefficient or the dynamic friction coefficient.

[0023] In one possible implementation, the vehicle parameters further include driving parameters of the vehicle in a driving state, and the determining module is further configured to determine a first correction factor using the driving parameters; and to correct the tire footprint length and the tire footprint width using the first correction factor to obtain a corrected tire footprint length and a corrected tire footprint width;

[0024] The determining module is configured to determine the first tire kingpin associated parameter using the corrected tire footprint length, the corrected tire footprint width, and the first kingpin offset.

[0025] In one possible implementation, the vehicle parameters further include driving parameters of the vehicle in a driving state, and the determining module is further configured to determine a first correction factor using the driving parameters; and to correct the tire footprint length and the tire footprint width using the first correction factor to obtain a corrected tire footprint length and a corrected tire footprint width;

[0026] The determining module is configured to determine the second tire kingpin associated parameter using the corrected tire footprint length, the corrected tire footprint width, and the second kingpin offset.

[0027] On the other hand, an embodiment of the present application provides a vehicle, comprising: a vehicle body and a vehicle control system, the vehicle control system being configured to execute any of the above-mentioned methods for determining the steering rack force on vehicle parameters corresponding to the vehicle body.

[0028] The technical solution provided by this application brings at least the following beneficial effects:

[0029] This application decouples the two wheels and uses their friction torque and aligning torque to determine the rotational resistance torque. This improves the accuracy of the rotational resistance torque determination by taking into account the asymmetry of the forces acting on the two wheels during vehicle steering. Furthermore, the rotational resistance torque is used to calculate the first and second tie rod forces, ultimately yielding the steering rack force, thus improving the accuracy of the steering rack force determination.

[0030] In addition, accurate steering rack force can improve the accuracy of matching with the vehicle steering system, so that the vehicle steering system can provide the vehicle with appropriate power assistance, improve vehicle handling stability and driving safety; it can also avoid component redundancy caused by improper selection and lead to cost waste by matching the accurate vehicle steering system. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0032] Figure 1 This is a schematic diagram of an implementation environment provided by an embodiment of the present application;

[0033] Figure 2 is a flow chart of a method for determining steering rack force provided in an embodiment of the present application;

[0034] Figure 3 This is a schematic diagram of the mechanical forces on the left wheel of a vehicle provided in an embodiment of the present application;

[0035] Figure 4 It is a structural schematic diagram of a steering rack force determination device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0036] In order to make the objectives, technical solutions and advantages of this application clearer, the implementation methods of this application will be further described in detail below with reference to the accompanying drawings.

[0037] It should be noted that the terms "first," "second," and the like in this application are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. Instead, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0038] With the development of the automotive industry, the suspension structures used in vehicles are becoming increasingly complex. During vehicle steering, the control arms, steering knuckles, and other components of the suspension structure transmit force to the steering rod, which is ultimately converted into steering rack force, which is used to control vehicle steering. Therefore, the accuracy of the steering rack force is crucial to the vehicle.

[0039] In addition, the steering rack force is also used to select the vehicle steering system. Among them, the vehicle steering system is mainly an electronic power steering system (EPS), which uses an electric motor to assist the driver in steering, replacing the traditional hydraulic power steering system. EPS detects the steering wheel rotation angle and speed through sensors, and then accurately controls the power assist of the electric motor according to the vehicle speed and steering requirements to provide appropriate steering assistance. Different vehicle parameters require different types of EPS, among which EPS includes but is not limited to column-assisted EPS (C-EPS), dual-pinion-assisted EPS (DP-EPS) and rack-assisted EPS (R-EPS).

[0040] A vehicle steering system with accurate steering rack force matching not only fully utilizes the performance advantages of EPS, improving vehicle handling and safety, but also avoids component redundancy and cost waste caused by improper selection. Therefore, this application provides a method for determining steering rack force to improve the accuracy of the determined rack force.

[0041] Figure 1 This is a schematic diagram of an implementation environment provided by an embodiment of the present application. Figure 1 As shown, the implementation environment may include a vehicle 101 and a vehicle control system 102, where the vehicle control system 102 is used to control the vehicle 101 to perform corresponding operations. The vehicle control system 102 may be located in the vehicle 101, for example, the vehicle control system 102 is an onboard terminal; the vehicle control system 102 may also be located outside the vehicle 101, for example, the vehicle control system 102 is a cloud control system.

[0042] The vehicle control system 102 may be an independent server, or the vehicle control system 102 may be a server cluster composed of multiple servers that implement different functions, or the vehicle control system 102 may be a cloud computing center.

[0043] Vehicle 101 includes, but is not limited to, gasoline-powered vehicles, electric vehicles, hybrid vehicles, and gas-powered vehicles. Vehicle 101 is equipped with a power steering system (EPS). Vehicle 101 may also have wireless communication capabilities. Vehicle 101 may be equipped with a communication module supporting wireless or wired communication technology. Vehicle 101 exchanges data with vehicle control system 102 via the communication module.

[0044] Based on the above Figure 1 In the implementation environment shown, an embodiment of the present application provides a method for determining steering rack force. Figure 2 This is a flow chart of a method for determining steering rack force provided by an embodiment of the present application. Figure 2 As shown, this method can be Figure 1 The method may include steps 201 to 204.

[0045] In step 201 , vehicle parameters of the vehicle are obtained.

[0046] In an exemplary embodiment of the present application, vehicle parameters include but are not limited to the full load of the front axle, the friction coefficient between the tire and the ground, the tire footprint length, the tire footprint width, the first kingpin offset, the second kingpin offset, the first kingpin inclination angle, the second kingpin inclination angle, the first maximum turning angle, the second maximum turning angle, the first kingpin castor angle, the second kingpin castor angle, the tire rolling radius, the first lever arm (the lever arm from the left side tie rod of the vehicle to the kingpin axis), the second lever arm (the lever arm from the right side tie rod of the vehicle to the kingpin axis), the first angle (the angle between the left side tie rod of the vehicle and the rack), the second angle (the angle between the right side tie rod of the vehicle and the rack), tire material data, tire pressure data and driving parameters.

[0047] The fully loaded front axle load refers to the total weight borne by the front axle when the vehicle is fully loaded. It is measured directly using a weighing device and is typically expressed in Newtons (N) or kilograms (kg). The fully loaded front axle load is an important indicator of the front axle's load-bearing capacity, affecting multiple aspects of the vehicle, including the suspension system, tire stress, and braking performance.

[0048] The friction coefficient between the tire and the ground refers to the ratio of the friction between the tire and the ground to the vertical force applied by the tire on the ground, reflecting the adhesion between the tire and the ground. When the vehicle is stationary, the friction coefficient between the tire and the ground is the static friction coefficient. When the vehicle is in motion, the friction coefficient between the tire and the ground is the dynamic friction coefficient. The contact state between the tire and the ground is constantly changing. The friction coefficient is affected by various factors such as vehicle speed, tire wear, and road conditions (such as accumulated water, oil stains, etc.). The dynamic friction coefficient can change as the vehicle travels. The method for obtaining the static friction coefficient and the dynamic friction coefficient is described in detail in step 202 and will not be repeated here.

[0049] Tire footprint length refers to the length of the tire's contact area in the direction of travel, typically measured in millimeters (mm) or centimeters (cm). Tire footprint width refers to the width of the tire's contact area perpendicular to the direction of travel, measured in the same units as the tire footprint length. For example, a camera can be used to capture images of the tire's contact area, analyze and process the captured images, and then use image processing software to measure the footprint length and width.

[0050] The first kingpin offset refers to the offset distance between the left wheel kingpin axis (suspension kingpin axis) and the tire's contact patch center in the lateral direction of the vehicle, also known as the left wheel kingpin offset. The second kingpin offset refers to the offset distance between the right wheel kingpin axis and the tire's contact patch center in the lateral direction of the vehicle, also known as the right wheel kingpin offset. For example, using a three-dimensional coordinate measuring machine or laser measuring equipment, the position of the kingpin axis and the contact patch centers of the left and right tires are measured. The difference in the distance between the contact patch centers of the left and right tires and the kingpin axis in the lateral direction of the vehicle is then calculated to obtain the first and second kingpin offsets.

[0051] The first kingpin inclination angle refers to the angle at which the left wheel's kingpin axis tilts inward within the vehicle's transverse plane, also known as the left wheel kingpin inclination angle. The second kingpin inclination angle refers to the angle at which the right wheel's kingpin axis tilts inward within the vehicle's transverse plane, also known as the right wheel kingpin inclination angle. The first and second kingpin inclination angles are determined by directly reading the angle values from an angle measuring instrument (such as an electronic level or a dedicated angle measuring tool) mounted on the kingpin axis.

[0052] The primary castor angle is the angle at which the left wheel's kingpin axis tilts rearward in the vehicle's longitudinal plane, also known as the left wheel castor angle. The secondary castor angle is the angle at which the right wheel's kingpin axis tilts rearward in the vehicle's longitudinal plane, also known as the right wheel castor angle. The method for obtaining these angles is similar to that for the kingpin inclination angle: using an angle measuring instrument mounted on the kingpin axis, measure the inclination angle of the kingpin axis in the vehicle's longitudinal plane to obtain the primary and secondary castor angles.

[0053] The first maximum turning angle refers to the maximum angle the left wheel can reach during steering, also known as the left wheel maximum turning angle. The second maximum turning angle refers to the maximum angle the right wheel can reach during steering, also known as the right wheel maximum turning angle. To determine the maximum turning angles, place the vehicle on a horizontal turntable, slowly rotate the steering wheel to its limit, and record the maximum deflection angles of the left and right wheels using the turntable scale or angle encoder. Alternatively, use real-time data from the on-board steering angle sensor to extract the limit turning angle values and determine the corresponding maximum turning angles for both tires.

[0054] The rolling radius of a tire is the distance from the center of the tire to the road surface when the tire is rolling under load. This is determined by measuring the tire's free radius (the radius of the tire when it is unloaded) and the amount of deformation it undergoes under load. Alternatively, specialized measuring equipment can be used to directly measure the distance from the tire center to the road surface while the vehicle is stationary and the tire is under load.

[0055] The first moment arm is the vertical distance from the vehicle's left tie rod to the kingpin axis; the second moment arm is the vertical distance from the vehicle's right tie rod to the kingpin axis. Use a 3D coordinate measuring machine or laser measuring equipment to accurately measure the positions of the left and right tie rods and the kingpin axis. Then, calculate the vertical distances from the left and right tie rods to the kingpin axis to determine the first and second moment arms.

[0056] The first angle is the angle between the left tie rod and the rack; the second angle is the angle between the right tie rod and the rack. Install an angle meter at the connection between the left tie rod and the rack, and at the connection between the right tie rod and the rack. Directly measure the two angles to obtain the first and second angles.

[0057] Tire material data includes information such as the type of rubber used and tire hardness. This data is inherent to the tire and is typically provided by the tire manufacturer. It can be obtained by consulting the tire's product specifications, technical manuals, and other methods.

[0058] Tire pressure data refers to the pressure of the air inside the tire. The tire is equipped with a built-in tire pressure sensor, and tire pressure data is obtained by acquiring sensor data from the pressure sensor.

[0059] Driving parameters refer to various data involved in the vehicle's driving process, such as vehicle speed, acceleration, engine speed, gear position, etc. Vehicle speed can be measured by measuring the wheel speed through the vehicle's wheel speed sensor and combining it with the tire's rolling radius. The vehicle's speed can also be directly measured using the Global Positioning System (GPS). Acceleration can be measured in real time in all directions by installing an accelerometer on the vehicle. Engine speed can be measured by measuring the engine crankshaft speed through the engine speed sensor. Gear position information can be obtained through real-time monitoring of the vehicle's transmission control system.

[0060] Figure 3 This is a schematic diagram of the mechanical force on the left wheel of a vehicle provided in an embodiment of the present application. Figure 3As shown, the vehicle includes a steering wheel 301, a universal joint 302, a steering gear 303, a first (left) tie rod 304, a steering hitch 305, a first (left) wheel 306, and a rack 307. The steering wheel 301 is a driver-controlled input source, generating a steering demand by rotating it. The universal joint 302 is a transmission component connecting the steering wheel 301 and the steering gear 303, responsible for transmitting the rotational motion of the steering wheel 301. The steering gear 303 is used to convert the rotational motion input by the steering wheel 301 into linear motion of the rack 307. The first (left) tie rod 304 is used to convert the linear driving force of the rack 307 into a force that pushes the first (left) wheel 306 to deflect. The steering hitch 305 is used to connect the first (left) wheel 306 to the suspension and can rotate about a kingpin (not shown in the figure) to drive the first (left) wheel 306 to steer. The first (left) wheel 306 is used to perform the steering action.

[0061] Figure 3 The first angle (α1), the first pull rod force (F1), the vehicle steering rack force (F r ), steering resistance torque (M) and first lever arm (L1). Among them, the first angle (α1) is the angle between the first (left) tie rod 304 and the rack 307 of the vehicle; the first tie rod force (F1) is the force exerted by the first (left) tie rod 304 on the universal joint 302; the steering resistance torque (M) is the steering resistance torque corresponding to the first (left) wheel 306; the vehicle's steering rack force (F r ) is the force exerted by the rack 307 on the first (left) tie rod 304; the first lever arm (L1) is the lever arm from the first (left) tie rod 304 of the vehicle to the kingpin axis.

[0062] It should be noted that the content of vehicle parameters and the method of obtaining vehicle parameters in this application are for illustrative purposes only. They can be adjusted based on actual calculation requirements during the calculation of rack force, and this application does not impose any restrictions on this.

[0063] In step 202 , a first friction torque, a second friction torque, a first aligning torque, and a second aligning torque of the vehicle are determined using vehicle parameters.

[0064] In an exemplary embodiment of the present application, the process of determining the first friction torque of the vehicle using vehicle parameters includes: determining the first tire kingpin associated parameter using the tire footprint length, tire footprint width and first kingpin offset; and determining the first friction torque of the vehicle using the full load of the front axle, the friction coefficient between the tire and the ground and the first tire kingpin associated parameter.

[0065] For example, the square of the tire footprint length (a1), the ratio of the square of the tire footprint width (b) to 16, and the square sum of the first kingpin offset (K1) are calculated, and the square root of the square sum is taken to obtain the first tire kingpin association parameter: Calculate the product of the first tire kingpin associated parameter, the front axle full load (G), and the friction coefficient between the tire and the ground (μ) and 1 / 2 to obtain the first friction torque (M f1 ). That is, the first friction torque (M f1 ) satisfies Formula 1:

[0066]

[0067] The various parameters of formula (1) have been explained above and will not be repeated here.

[0068] In an exemplary embodiment of the present application, the vehicle parameters include the full load of the front axle, the friction coefficient between the tire and the ground, the tire footprint length, the tire footprint width, and the second kingpin offset. The process of determining the second friction torque of the vehicle using the vehicle parameters includes: determining the second tire kingpin associated parameter using the tire footprint length, the tire footprint width, and the second kingpin offset; determining the second friction torque of the vehicle using the full load of the front axle, the friction coefficient between the tire and the ground, and the second tire kingpin associated parameter.

[0069] For example, the square of the tire footprint length (a1), the ratio of the square of the tire footprint width (b) to 16, and the sum of the squares of the second kingpin offset (K2) are calculated, and the square root of the sum of the squares is taken to obtain the second tire kingpin association parameter: Calculate the second tire kingpin related parameters, the front axle full load (G) and the product of the tire and ground friction coefficient (μ) and 1 / 2 to obtain the second friction torque (M f2 ). That is, the second friction torque (M f2 ) satisfies formula (2):

[0070]

[0071] The various parameters of formula (2) have been explained above and will not be repeated here.

[0072] The present embodiment calculates the friction torque of the vehicle's left and right wheels by combining tire footprint length, tire footprint width, kingpin offset, vehicle load, and friction coefficient. The tire contact patch shape (tire footprint length, tire footprint width) and the kingpin's spatial position (kingpin offset) are converted into comprehensive tire kingpin-related parameters (a first tire kingpin-related parameter and a second tire kingpin-related parameter). This fully considers the synergy between the tire and suspension system, significantly improving the accuracy of torque calculation compared to traditional calculation methods that rely solely on a single parameter. Furthermore, by combining the full front axle load and the friction coefficient, it can dynamically reflect changes in friction under different load conditions and road conditions, providing a reliable theoretical basis for vehicle steering system design, suspension tuning, and active safety control (such as torque distribution in ESP systems), effectively optimizing vehicle handling stability and safety.

[0073] In an exemplary embodiment of the present application, before calculating the first friction torque and the second friction torque, the friction coefficient between the vehicle's tires and the ground may also be determined. The process of determining the friction coefficient between the vehicle's tires and the ground includes obtaining environmental parameters of the vehicle, the environmental parameters including at least one of ground roughness, temperature, or humidity; determining a static friction coefficient or a dynamic friction coefficient using tire material data, tire pressure data, and the environmental parameters, wherein the static friction coefficient represents the friction coefficient between the tires and the ground when the vehicle is stationary, and the dynamic friction coefficient represents the friction coefficient between the tires and the ground when the vehicle is moving; and determining the friction coefficient between the tires and the ground based on the static friction coefficient or the dynamic friction coefficient.

[0074] Exemplarily, multiple types of sensors are installed on the outside of the vehicle for real-time collection of environmental parameters. For example, the sensor includes a surface roughness meter (such as a laser profilometer) for measuring surface roughness; the sensor includes a temperature sensor (such as a thermocouple, thermistor, etc.) for measuring ambient temperature; the sensor includes a humidity sensor (such as a capacitive humidity sensor, a resistive humidity sensor, etc.) for measuring ambient humidity. It should be noted that the environmental parameters used in this application are only failure descriptions, and other environmental parameters can also be obtained based on actual conditions, and this application does not impose any restrictions on this.

[0075] When the vehicle is stationary, obtain the tire material data, tire pressure data, and influencing factors corresponding to the environmental parameters. For example, the data correction library includes correction conditions and the influencing factors corresponding to the correction conditions. Compare the tire material data, tire pressure data, and environmental parameters with each correction condition to obtain the influencing factors that meet the correction conditions. After obtaining the influencing factors, calculate the static friction coefficient based on formula (3) and formula (4):

[0076] F f =μN Formula (3)

[0077] μ=M1μ1 Formula (4)

[0078] In the above formulas (3) and (4), F f is the friction force, μ1 is the initial static friction coefficient, N is the vertical positive pressure (determined based on the vehicle weight), M1 is the influencing factor, and μ is the static friction coefficient.

[0079] When the vehicle is in motion, in addition to tire material data, tire pressure data, and environmental parameters, the dynamic friction coefficient is determined by combining vehicle driving parameters (such as tire slip). The dynamic friction coefficient is calculated using formula (5):

[0080] μ=D·sin{C·arctan[B·λ-E·(B·λ-arctan(B·λ))]} Formula (5)

[0081] In the above formula (5), μ is the dynamic friction coefficient, λ is the tire slip rate, B is the stiffness factor, C is the shape factor, D is the peak friction coefficient, and E is the curvature factor. v is the vehicle's nominal velocity, w is the tire's angular velocity, and r is the tire's rolling radius. The stiffness factor, B, reflects the stiffness of the tire's friction characteristic curve—that is, how quickly the tire's friction coefficient changes at different slip rates. The shape factor, C, reflects the shape of the tire's friction characteristic curve, influencing how the friction coefficient changes with slip rate. The maximum friction coefficient, D, reflects the maximum friction coefficient achievable under specific conditions and is the limit of friction between the tire and the road. The curvature factor, E, adjusts the curvature of the tire's friction characteristic curve to better reflect actual conditions. These parameters typically require experimental determination. During the experiment, the tire's friction coefficient is measured at different slip rates under different road conditions, tire types, and vehicle loads. Data fitting is then used to determine the B, C, D, and E values that best fit the experimental data.

[0082] According to the actual state of the vehicle (stationary or moving), the corresponding static friction coefficient or dynamic friction coefficient is selected as the friction coefficient between the tire and the ground.

[0083] The embodiment of the present application comprehensively considers the influence of multiple factors such as tire material data, tire pressure data and environmental parameters on the friction coefficient. Compared with traditional estimation methods based only on experience or simple parameters, it can more accurately reflect the actual friction conditions between the tire and the ground, and improve the accuracy of calculating the friction coefficient between the tire and the ground, thereby improving the first friction torque and second friction torque of the vehicle determined based on the friction coefficient between the tire and the ground, laying the foundation for the subsequent calculation of the steering rack force.

[0084] Optionally, in the process of determining the first tire kingpin associated parameters and the second tire kingpin associated parameters, the driving parameters may also be used to determine a first correction factor; the tire footprint length and the tire footprint width may be corrected using the first correction factor to obtain a corrected tire footprint length and a corrected tire footprint width; the first tire kingpin associated parameters may be determined using the corrected tire footprint length, the corrected tire footprint width, and the first kingpin offset; and the second tire kingpin associated parameters may be determined using the corrected tire footprint length, the corrected tire footprint width, and the second kingpin offset.

[0085] For example, driving parameters are obtained through various sensors installed on the vehicle. For example, wheel speed sensors are used to obtain wheel rotation information, acceleration sensors are used to obtain the vehicle's longitudinal and lateral acceleration, and steering wheel angle sensors are used to obtain the steering wheel's rotation angle. Driving parameters can reflect the dynamic characteristics of the vehicle under different driving conditions, such as acceleration, deceleration, and cornering.

[0086] Obtain a mapping model between driving parameters and correction factors. For example, under different combinations of vehicle speed, acceleration, and steering angle, measure the actual changes in the impact of tire footprint length and width on tire kingpin-related parameters. Then, use data analysis methods (such as regression analysis and neural networks) to establish a mapping model between driving parameters and correction factors.

[0087] Substitute the acquired driving parameters into the mapping model to calculate the first correction factor. The first correction factor is a coefficient that reflects the impact of driving conditions on the tire footprint length and width. The calculated first correction factor is used to correct the tire footprint length (a1) and tire footprint width (b) to obtain the corrected tire footprint length and tire footprint width. The corrected tire footprint length is the product of the tire footprint length (a1) and the first correction factor, and the corrected tire footprint width is the product of the tire footprint width (b) and the first correction factor.

[0088] Then, the first tire kingpin associated parameter and the second tire kingpin associated parameter are calculated using the corrected tire footprint length and the corrected tire footprint width, thereby obtaining the first friction torque and the second friction torque. The calculation of the first tire kingpin associated parameter, the second tire kingpin associated parameter, the first friction torque and the second friction torque has been described in the above formulas (1) and (2), and will not be repeated here.

[0089] In the embodiments of the present application, during vehicle driving, the contact characteristics of the tires with the ground change due to acceleration, deceleration, cornering, and other maneuvers, resulting in differences in the tire footprint length and width compared to when the vehicle is stationary. By using driving parameters to determine a correction factor and then correcting the tire footprint length and width, the system can more accurately reflect the actual tire-ground contact conditions during driving, thereby improving the calculation accuracy of the first and second tire kingpin-related parameters, and thus improving the accuracy of the vehicle's steering rack force calculation.

[0090] In an exemplary embodiment of the present application, the vehicle parameters include a front axle full load, a first kingpin inclination angle, a first maximum turning angle, a second maximum turning angle, a first kingpin caster angle, a first kingpin offset, and a tire rolling radius. The process of determining the first return torque using the vehicle parameters includes: determining a turning angle parameter based on the first maximum turning angle and the second maximum turning angle; determining a first lever arm coefficient based on the first kingpin offset, the first kingpin inclination angle, and the tire rolling radius; and determining the first return torque using the front axle full load, the first kingpin inclination angle, the turning angle parameter, the first kingpin caster angle, and the first lever arm coefficient.

[0091] Exemplarily, the angle parameter is the sine value of the average angle of the first maximum angle (β1) and the second maximum angle (β2), that is, The steering angle parameter reflects the impact of the maximum left and right wheel steering angles on the vehicle during steering. The first moment arm coefficient is the sum of the first parameter (K1) and the second parameter (cosδ1), where the first parameter is the product of the first kingpin offset (K1) and the cosine of the first kingpin inclination angle (δ1), and the second parameter is the product of the tire rolling radius (r) and the sine of the first kingpin inclination angle (δ1). In other words, the first moment arm coefficient is K1cosδ1 + rsinδ1.

[0092] Then, the first aligning moment (M) is determined based on the full load of the front axle, the first kingpin inclination angle, the angle parameter, the first kingpin caster angle, and the first lever arm coefficient. b1 ), where the first aligning moment (M b1 ) satisfies formula (6):

[0093]

[0094] In formula (6), G is the full load of the front axle, γ1 is the first kingpin caster angle, and the other parameters have been explained above and will not be repeated here.

[0095] In an exemplary embodiment of the present application, the vehicle parameters include the full load of the front axle, the second kingpin inclination angle, the first maximum turning angle, the second maximum turning angle, the second kingpin caster angle, the second kingpin offset and the tire rolling radius. The process of determining the second righting torque using the vehicle parameters includes: determining the angle parameter based on the first maximum turning angle and the second maximum turning angle; determining the second lever arm coefficient based on the second kingpin offset, the second kingpin inclination angle and the tire rolling radius; determining the second righting torque using the full load of the front axle, the second kingpin inclination angle, the angle parameter, the second kingpin caster angle and the second lever arm coefficient.

[0096] Exemplarily, the angle parameter is the sine value of the average angle of the first maximum angle (β1) and the second maximum angle (β2), that is, The steering angle parameter reflects the impact of the maximum left and right wheel steering angles on the vehicle during steering. The second moment arm coefficient is the sum of the third and fourth parameters. The third parameter is the product of the second kingpin offset (K2) and the cosine (cosδ2) of the second kingpin inclination angle (δ2), and the fourth parameter is the product of the tire rolling radius (r) and the sine (sinδ2) of the second kingpin inclination angle (δ2). In other words, the second moment arm coefficient is K2cosδ2 + rsinδ2.

[0097] Then, the second aligning moment (M) is determined based on the full load of the front axle, the second kingpin inclination angle, the angle parameter, the second kingpin caster angle, and the second lever arm coefficient. b2 ), where the second aligning moment (M b2 ) satisfies formula (7):

[0098]

[0099] In formula (7), G is the full load of the front axle, γ2 is the second kingpin caster angle, and the other parameters have been explained above and will not be repeated here.

[0100] When determining the first return torque and the second return torque, the embodiment of the present application determines the angle parameters based on the first maximum turning angle and the second maximum turning angle, which can cover the extreme steering conditions of the wheels on both sides when the vehicle is turning, and accurately reflect the actual steering angle changes of the vehicle; the lever arm coefficient is determined based on the kingpin offset, the kingpin inclination angle and the tire rolling radius, and fully considers the influence of the kingpin geometric position and the tire rolling characteristics on the lever arm; finally, the return torque is determined using the full load of the front axle, the kingpin inclination angle, the angle parameters, the kingpin caster angle and the lever arm coefficient, and the effects of multiple key factors of the vehicle in the steering process are comprehensively considered, so that the calculated first return torque and the second return torque are more in line with the actual steering characteristics of the vehicle, and the accuracy of determining the first return torque and the second return torque is improved, thereby improving the accuracy of calculating the steering rack force using the first return torque and the second return torque.

[0101] In step 203 , a rotational resistance torque is determined based on the first friction torque, the second friction torque, the first aligning torque, and the second aligning torque.

[0102] In the exemplary embodiment of the present application, the rotational resistance torque (M) is the sum of the first friction torque, the second friction torque, the first aligning torque, and the second aligning torque. The rotational resistance torque is calculated based on formula (8):

[0103] M=M f1 +M f2 +M b1 +M b2 Formula (8)

[0104] In the above formula (8), M f1 is the first friction torque of the vehicle, M f2 is the second friction torque of the vehicle, M b1 is the first positive torque, M b2 is the second positive torque.

[0105] In step 204 , a first tie rod force and a second tie rod force are determined using the rotational resistance torque and vehicle parameters, and a steering rack force of the vehicle is determined based on the first tie rod force and the second tie rod force.

[0106] In an exemplary embodiment of the present application, the vehicle parameters also include a first lever arm and a second lever arm. The process of determining the first tie rod force and the second tie rod force using the rotational resistance torque and the vehicle parameters includes: determining the first tie rod force using the rotational resistance torque and the first lever arm, and determining the second tie rod force using the rotational resistance torque and the second lever arm. The first lever arm is the lever arm from the first tie rod of the vehicle to the kingpin axis, and the second lever arm is the lever arm from the second tie rod of the vehicle to the kingpin axis.

[0107] The first tie rod is the tie rod on the left side of the vehicle, and the second tie rod is the tie rod on the right side of the vehicle. The first tie rod force (F1) is half the ratio of the rotational resistance torque (M) to the first lever arm (L1), and the second tie rod force (F2) is half the ratio of the rotational resistance torque (M) to the second lever arm (L2). The first tie rod force (F1) is calculated based on formula (9), and the second tie rod force (F2) is calculated based on formula (10):

[0108]

[0109] The embodiment of the present application determines the first tie rod force and the second tie rod force through the relationship between the rotational resistance torque, the first lever arm and the second lever arm, which can more accurately quantify the mechanical action distance of the tie rod on the kingpin axis during the rotation process, so that the first tie rod force and the second tie rod force are more in line with the actual situation of the vehicle, and provide accurate data support for the design and optimization of key components such as the vehicle steering system and suspension system.

[0110] In an exemplary embodiment of the present application, after determining the first and second tie rod forces, the vehicle's steering rack force can also be determined based on the first and second tie rod forces. The vehicle parameters also include a first angle and a second angle. The process of determining the vehicle's steering rack force based on the first and second tie rod forces includes: determining the first steering rack force based on the first tie rod force and the first angle, where the first angle is the angle between the vehicle's first tie rod and the rack; determining the second steering rack force based on the second tie rod force and the second angle, where the second angle is the angle between the vehicle's second tie rod and the rack; and determining the vehicle's steering rack force using the first and second steering rack forces.

[0111] For example, the first steering rack force is the ratio of the first tie rod force (F1) to the cosine value (cosα1) of the first angle (α1), that is, the first steering rack force is The second steering rack force is the ratio of the second tie rod force (F2) to the cosine value (cosα2) of the second angle (α2), that is, the second steering rack force is The vehicle's steering rack force (F r ) is the sum of the first steering rack force and the second steering rack force. The vehicle's steering rack force is calculated based on formula (11):

[0112]

[0113] By considering the angle between the first tie rod and the rack (first angle) and the angle between the second tie rod and the rack (second angle), the embodiment of the present application can more accurately analyze the mechanical conversion relationship of the tie rod force in the process of being transmitted to the steering rack. The size of the angle will affect the direction and magnitude of force transmission, so that the calculation of the vehicle's steering rack force is more in line with the mechanical characteristics of the vehicle's actual steering system, thereby improving the accuracy of calculating the vehicle's steering rack force.

[0114] This application decouples the two wheels and uses their friction torque and aligning torque to determine the rotational resistance torque. This improves the accuracy of the rotational resistance torque determination by taking into account the asymmetry of the forces acting on the two wheels during vehicle steering. Furthermore, the rotational resistance torque is used to calculate the first and second tie rod forces, ultimately yielding the steering rack force, thus improving the accuracy of the steering rack force determination.

[0115] In addition, accurate steering rack force can improve the accuracy of matching with the vehicle steering system, so that the vehicle steering system can provide the vehicle with appropriate power assistance, improve vehicle handling stability and driving safety; it can also avoid component redundancy caused by improper selection and lead to cost waste by matching the accurate vehicle steering system.

[0116] The present application also provides a device for determining steering rack force. Figure 4: is a schematic structural diagram of a device for determining steering rack force provided in an embodiment of the present application, such as Figure 4 As shown, the device includes:

[0117] An acquisition module 401 is used to acquire vehicle parameters of a vehicle;

[0118] A determination module 402 is configured to determine a first friction torque, a second friction torque, a first aligning torque, and a second aligning torque of the vehicle using vehicle parameters;

[0119] The determining module 402 is further configured to determine a rotational resistance torque based on the first friction torque, the second friction torque, the first aligning torque, and the second aligning torque;

[0120] The determination module 402 is further configured to determine a first tie rod force and a second tie rod force using the rotational resistance torque and vehicle parameters, and determine a steering rack force of the vehicle based on the first tie rod force and the second tie rod force.

[0121] In one possible implementation, the vehicle parameters include a fully loaded front axle, a coefficient of friction between the tire and the ground, a tire footprint length, a tire footprint width, and a first kingpin offset. Determination module 402 is configured to determine a first tire kingpin-associated parameter using the tire footprint length, the tire footprint width, and the first kingpin offset; and to determine a first friction torque of the vehicle using the fully loaded front axle, the coefficient of friction between the tire and the ground, and the first tire kingpin-associated parameter.

[0122] In one possible implementation, the vehicle parameters include a fully loaded front axle, a coefficient of friction between the tire and the ground, a tire footprint length, a tire footprint width, and a second kingpin offset. Determination module 402 is configured to determine a second tire kingpin associated parameter using the tire footprint length, the tire footprint width, and the second kingpin offset; and to determine a second friction torque of the vehicle using the fully loaded front axle, the coefficient of friction between the tire and the ground, and the second tire kingpin associated parameter.

[0123] In one possible implementation, the vehicle parameters include a front axle full load, a first kingpin inclination angle, a first maximum turning angle, a second maximum turning angle, a first kingpin caster angle, a first kingpin offset, and a tire rolling radius. The determination module 402 is configured to determine a turning angle parameter based on the first maximum turning angle and the second maximum turning angle; determine a first lever arm coefficient based on the first kingpin offset, the first kingpin inclination angle, and the tire rolling radius; and determine a first self-aligning torque using the front axle full load, the first kingpin inclination angle, the turning angle parameter, the first kingpin caster angle, and the first lever arm coefficient.

[0124] In one possible implementation, the vehicle parameters include a fully loaded front axle, a second kingpin inclination angle, a first maximum turning angle, a second maximum turning angle, a second kingpin caster angle, a second kingpin offset, and a tire rolling radius. The determination module 402 is configured to determine a turning angle parameter based on the first maximum turning angle and the second maximum turning angle; determine a second lever arm coefficient based on the second kingpin offset, the second kingpin inclination angle, and the tire rolling radius; and determine a second self-aligning torque using the fully loaded front axle, the second kingpin inclination angle, the turning angle parameter, the second kingpin caster angle, and the second lever arm coefficient.

[0125] In one possible implementation, the vehicle parameters also include a first lever arm and a second lever arm, and a determination module 402 is used to determine the first tie rod force using the rotational resistance torque and the first lever arm, and to determine the second tie rod force using the rotational resistance torque and the second lever arm, wherein the first lever arm is the lever arm from the first tie rod of the vehicle to the kingpin axis, and the second lever arm is the lever arm from the second tie rod of the vehicle to the kingpin axis.

[0126] In one possible implementation, the vehicle parameters also include a first angle and a second angle, and a determination module 402 is used to determine a first steering rack force based on a first tie rod force and a first angle, where the first angle is the angle between the first tie rod and the rack of the vehicle; determine a second steering rack force based on a second tie rod force and a second angle, where the second angle is the angle between the second tie rod and the rack of the vehicle; and determine the steering rack force of the vehicle using the first steering rack force and the second steering rack force.

[0127] In a possible implementation, the vehicle parameters further include tire material data and tire pressure data. The acquisition module 401 is further configured to acquire environmental parameters of the vehicle, including at least one of ground roughness, temperature, or humidity.

[0128] Determination module 402 is further configured to determine a static friction coefficient or a dynamic friction coefficient using tire material data, tire pressure data, and environmental parameters. The static friction coefficient represents the friction coefficient between the tire and the ground when the vehicle is stationary, and the dynamic friction coefficient represents the friction coefficient between the tire and the ground when the vehicle is moving. The friction coefficient between the tire and the ground is determined based on the static friction coefficient or the dynamic friction coefficient.

[0129] In one possible implementation, the vehicle parameters further include driving parameters of the vehicle in a driving state, and the determining module 402 is further configured to determine a first correction factor using the driving parameters; and to correct the tire footprint length and the tire footprint width using the first correction factor to obtain a corrected tire footprint length and a corrected tire footprint width.

[0130] The determination module 402 is configured to determine a first tire kingpin associated parameter using the corrected tire footprint length, the corrected tire footprint width, and the first kingpin offset.

[0131] In one possible implementation, the vehicle parameters further include driving parameters of the vehicle in a driving state, and the determining module 402 is further configured to determine a first correction factor using the driving parameters; and to correct the tire footprint length and the tire footprint width using the first correction factor to obtain a corrected tire footprint length and a corrected tire footprint width.

[0132] The determination module 402 is configured to determine a second tire kingpin associated parameter using the corrected tire footprint length, the corrected tire footprint width, and the second kingpin offset.

[0133] This application decouples the two wheels and uses their friction torque and aligning torque to determine the rotational resistance torque. This improves the accuracy of the rotational resistance torque determination by taking into account the asymmetry of the forces acting on the two wheels during vehicle steering. Furthermore, the rotational resistance torque is used to calculate the first and second tie rod forces, ultimately yielding the steering rack force, thus improving the accuracy of the steering rack force determination.

[0134] In addition, accurate steering rack force can improve the accuracy of matching with the vehicle steering system, so that the vehicle steering system can provide the vehicle with appropriate power assistance, improve vehicle handling stability and driving safety; it can also avoid component redundancy caused by improper selection and lead to cost waste by matching the accurate vehicle steering system.

[0135] It should be understood that the above-described apparatus, when implementing its functions, is merely illustrated by the division of the aforementioned functional modules. In actual applications, the aforementioned functions can be distributed among different functional modules as needed, i.e., the internal structure of the vehicle can be divided into different functional modules to complete all or part of the functions described above. Furthermore, the apparatus and method embodiments provided in the above-described embodiments are based on the same concept. The specific implementation process is detailed in the method embodiments and will not be further described here.

[0136] The present application may also provide a vehicle comprising: a vehicle body and a vehicle control system, the vehicle control system being configured to execute any of the aforementioned methods for determining the steering rack force on the vehicle body. The details of how the vehicle control system acquires vehicle parameters and determines the steering rack force based on the vehicle parameters have been described in detail above and will not be repeated here.

[0137] It should be understood that the term "plurality" used herein refers to two or more. "And / or" describes a relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone. The character " / " generally indicates an "or" relationship between the associated objects.

[0138] The above description is merely an exemplary embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A method for determining steering rack force, characterized in that: The method comprises: Get vehicle parameters of the vehicle; Determining a first friction torque, a second friction torque, a first aligning torque, and a second aligning torque of the vehicle using the vehicle parameters; determining a rotational resistance torque based on the first friction torque, the second friction torque, the first aligning torque, and the second aligning torque; A first tie rod force and a second tie rod force are determined using the rotational resistance torque and the vehicle parameters, and a steering rack force of the vehicle is determined based on the first tie rod force and the second tie rod force.

2. The method according to claim 1, characterized in that The vehicle parameters include a fully loaded front axle load, a friction coefficient between a tire and a ground surface, a tire footprint length, a tire footprint width, and a first kingpin offset. Determining a first friction torque of the vehicle using the vehicle parameters includes: Determining a first tire kingpin associated parameter using the tire footprint length, the tire footprint width, and the first kingpin offset; A first friction torque of the vehicle is determined using the full front axle load, the friction coefficient between the tire and the ground, and the first tire kingpin association parameter.

3. The method according to claim 1, characterized in that The vehicle parameters include a fully loaded front axle load, a friction coefficient between a tire and a ground surface, a tire footprint length, a tire footprint width, and a second kingpin offset. Determining the second friction torque of the vehicle using the vehicle parameters includes: determining a second tire kingpin associated parameter using the tire footprint length, the tire footprint width, and the second kingpin offset; A second friction torque of the vehicle is determined using the full front axle load, the friction coefficient between the tire and the ground, and the second tire kingpin association parameter.

4. The method according to claim 1, wherein The vehicle parameters include a front axle full load, a first kingpin inclination angle, a first maximum turning angle, a second maximum turning angle, a first kingpin caster angle, a first kingpin offset, and a tire rolling radius. Determining a first aligning torque using the vehicle parameters includes: determining a rotation angle parameter based on the first maximum rotation angle and the second maximum rotation angle; determining a first moment arm coefficient based on the first kingpin offset, the first kingpin inclination angle, and the tire rolling radius; The first aligning torque is determined using the front axle full load, the first kingpin inclination angle, the rotation angle parameter, the first kingpin castor angle, and the first lever arm coefficient.

5. The method according to claim 1, wherein The vehicle parameters include a front axle full load, a second kingpin inclination angle, a first maximum turning angle, a second maximum turning angle, a second kingpin caster angle, a second kingpin offset, and a tire rolling radius. Determining the second aligning torque using the vehicle parameters includes: determining a rotation angle parameter based on the first maximum rotation angle and the second maximum rotation angle; determining a second moment arm coefficient based on the second kingpin offset, the second kingpin inclination angle, and the tire rolling radius; The second aligning torque is determined using the front axle full load, the second kingpin inclination angle, the rotation angle parameter, the second kingpin caster angle, and the second lever arm coefficient.

6. The method according to any one of claims 1 to 5, characterized in that: The vehicle parameters further include a first lever arm and a second lever arm, and determining the first and second pull rod forces by using the rotational resistance torque and the vehicle parameters includes: The first tie rod force is determined using the rotational resistance torque and the first lever arm, and the second tie rod force is determined using the rotational resistance torque and the second lever arm. The first lever arm is the lever arm from the first tie rod of the vehicle to the kingpin axis, and the second lever arm is the lever arm from the second tie rod of the vehicle to the kingpin axis.

7. The method according to any one of claims 1 to 5, characterized in that: The vehicle parameters further include a first included angle and a second included angle, and determining the steering rack force of the vehicle based on the first tie rod force and the second tie rod force includes: determining a first steering rack force based on the first tie rod force and the first angle, wherein the first angle is an angle between the first tie rod of the vehicle and the rack; determining a second steering rack force based on the second tie rod force and the second included angle, wherein the second included angle is an included angle between the second tie rod of the vehicle and the rack; A steering rack force of the vehicle is determined using the first steering rack force and the second steering rack force.

8. The method according to claim 2 or 3, characterized in that The vehicle parameters also include tire material data and tire pressure data, and the method further includes: Acquiring environmental parameters of the vehicle, the environmental parameters including at least one of ground roughness, temperature, or humidity; Determining a static friction coefficient or a dynamic friction coefficient using the tire material data, the tire pressure data, and the environmental parameters, wherein the static friction coefficient represents a friction coefficient between the tire and the ground when the vehicle is stationary, and the dynamic friction coefficient represents a friction coefficient between the tire and the ground when the vehicle is moving; The friction coefficient between the tire and the ground is determined based on the static friction coefficient or the dynamic friction coefficient.

9. The method according to claim 2, characterized in that The vehicle parameters also include driving parameters of the vehicle in a driving state, and the method further includes: determining a first correction factor using the driving parameter; Correcting the tire footprint length and the tire footprint width using the first correction factor to obtain a corrected tire footprint length and a corrected tire footprint width; Determining a first tire kingpin associated parameter using the tire footprint length, the tire footprint width, and the first kingpin offset includes: The first tire kingpin associated parameter is determined using the corrected tire footprint length, the corrected tire footprint width, and the first kingpin offset.

10. The method according to claim 3, characterized in that The vehicle parameters also include driving parameters of the vehicle in a driving state, and the method further includes: determining a first correction factor using the driving parameter; Correcting the tire footprint length and the tire footprint width using the first correction factor to obtain a corrected tire footprint length and a corrected tire footprint width; Determining a second tire kingpin associated parameter using the tire footprint length, the tire footprint width, and the second kingpin offset includes: The second tire kingpin associated parameter is determined using the corrected tire footprint length, the corrected tire footprint width, and the second kingpin offset.

11. A device for determining steering rack force, characterized in that: The device comprises: An acquisition module, used to obtain vehicle parameters of the vehicle; a determination module, configured to determine a first friction torque, a second friction torque, a first aligning torque, and a second aligning torque of the vehicle using the vehicle parameters; The determining module is further configured to determine a rotational resistance torque based on the first friction torque, the second friction torque, the first aligning torque, and the second aligning torque; The determination module is further configured to determine a first tie rod force and a second tie rod force using the rotational resistance torque and the vehicle parameters, and determine a steering rack force of the vehicle based on the first tie rod force and the second tie rod force.

12. A vehicle, characterized in that: The vehicle comprises: Vehicle body; A vehicle control system is used to execute the steering rack force determination method described in any one of claims 1 to 10 above on vehicle parameters corresponding to the vehicle body.

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