Simulation processing method and device of vehicle ground clearance line, equipment and medium

Abstract

The application relates to the technical field of vehicle simulation, in particular to a simulation processing method and device for a vehicle ground clearance line, equipment and a medium, wherein the method comprises the following steps: acquiring response parameters of a vehicle under different simulation conditions; inversely deducing target positions and target widths of interference between a vehicle chassis and a road surface under different simulation conditions according to the response parameters; determining an initial vehicle ground clearance line according to the target positions and the target widths; inputting the initial vehicle ground clearance line into a target vehicle model; the target vehicle model outputs corresponding interference positions and interference amounts; and correcting the vehicle ground clearance line according to the interference positions and the interference amounts to generate a minimum ground clearance line of the vehicle. Thus, the problems that the estimation result is greatly deviated and the chassis bumping risk cannot be effectively evaluated due to the estimation of the ground clearance line according to the vehicle parameters in the related art are solved.

Description

Technical Field

[0001] This application relates to the field of vehicle simulation technology, and in particular to a method, apparatus, equipment and medium for simulating vehicle ground clearance lines. Background Technology

[0002] Vehicle passability is a key indicator of a vehicle's ability to navigate various complex road conditions and harsh terrains. In the early stages of vehicle layout design, to effectively mitigate the risk of collisions to chassis components (such as the subframe, fuel tank, and exhaust pipe), the minimum ground clearance line is used as a design reference boundary.

[0003] In related technologies, the minimum ground clearance line is mainly calculated based on static theoretical parameters such as the approach angle and departure angle of the vehicle. However, the minimum ground clearance line obtained by relying solely on theoretical parameters is often not accurate enough and cannot truly reflect the actual envelope space of the vehicle under harsh working conditions (such as going up or down steps or crossing obstacles). This can easily cause chassis components to be bumped or even damaged during actual road tests or use, thereby increasing the R&D costs and time cycle for subsequent rectification. Summary of the Invention

[0004] This application provides a simulation processing method, device, equipment, and medium for vehicle ground clearance lines, in order to solve the problems in related technologies where ground clearance lines are estimated based on vehicle parameters, resulting in large deviations in the estimation results and making it difficult to effectively assess the risk of chassis collisions.

[0005] The first aspect of this application provides a simulation processing method for vehicle ground clearance lines, comprising the following steps: obtaining response parameters of the vehicle under different simulation conditions; inferring the target position and target width of the vehicle chassis interfering with the road surface under different simulation conditions based on the response parameters; determining an initial vehicle ground clearance line based on the target position and target width; inputting the initial vehicle ground clearance line into a target vehicle model; the target vehicle model outputting the corresponding interference position and interference amount; and correcting the vehicle ground clearance line based on the interference position and interference amount to generate the minimum ground clearance line of the vehicle.

[0006] Optionally, the step of deducing the target position where the vehicle chassis interferes with the road surface under the target simulation condition based on the response parameters includes: identifying the duration corresponding to the time when the wheel center of the front and rear wheels of the vehicle is located directly above the step to the time when the tire fully contacts the ground under different simulation conditions; calculating the longitudinal displacement of the front and rear wheels of the vehicle during the landing process based on the duration and the preset speed; and deducing the target position where the vehicle chassis interferes with the road surface under the target simulation condition based on the longitudinal displacement.

[0007] Optionally, the step of back-calculating the target width of the vehicle chassis interfering with the road surface under different simulation conditions based on the response parameters includes: executing the target simulation conditions at a first preset speed and a second preset speed respectively, and obtaining the corresponding first longitudinal displacement and second longitudinal displacement; determining the target width of the vehicle chassis interfering with the road surface under different simulation conditions based on the difference between the first longitudinal displacement and the second longitudinal displacement.

[0008] Optionally, determining the vehicle ground clearance line based on the target position and target width includes: determining multiple ground clearance control points distributed longitudinally along the vehicle based on the target position, wherein the ground clearance control points correspond to risk locations where the vehicle may interfere with the road surface under different simulation conditions; determining the continuous coverage range of the target position along the vehicle's longitudinal direction based on the target width, and determining risk areas based on the continuous coverage range; constructing ground clearance line segments for different longitudinal regions of the vehicle based on the ground clearance control points, the risk areas, and preset ground clearance height constraints; and fusing the ground clearance line segments for different longitudinal regions of the vehicle to generate an initial ground clearance line covering the entire longitudinal range of the vehicle.

[0009] Optionally, the step of fusing the ground clearance segments of different longitudinal regions of the vehicle to generate an initial ground clearance line covering the entire longitudinal range of the vehicle includes: extracting a first type of control point located on the front side of the wheel and a second type of control point located on the rear side of the wheel from the ground clearance control points, as well as a preset ground clearance height constraint, and constructing ground clearance segments for the front and rear regions of the vehicle respectively; calculating the radius of the arc based on the vehicle wheelbase and a preset angle, and generating a ground clearance line for the middle region of the vehicle based on the radius of the arc; and fusing the ground clearance segments of the front and rear regions of the vehicle and the ground clearance line for the middle region of the vehicle to generate an initial ground clearance line covering the entire longitudinal range of the vehicle.

[0010] Optionally, before obtaining the response parameters of the vehicle at the target speed under different simulation conditions, the process includes: establishing a multi-body dynamics model of the whole vehicle including the suspension system, wheels and chassis structure; and establishing at least one simulation condition for evaluating the vehicle's passability, wherein the simulation condition includes at least one of an up-step condition, a down-step condition or a step condition with a slope.

[0011] A second aspect of this application provides a simulation processing device for vehicle ground clearance lines, comprising: an acquisition module for acquiring response parameters of a vehicle at a target speed under different simulation conditions; a reverse calculation module for reverse-calculating the target position and target width of the vehicle chassis interfering with the road surface under different simulation conditions based on the response parameters; and a correction module for determining an initial vehicle ground clearance line based on the target position and target width, inputting the initial vehicle ground clearance line into a target vehicle model, the target vehicle model outputting the corresponding interference position and interference amount, and correcting the vehicle ground clearance line based on the interference position and interference amount to generate the minimum ground clearance line of the vehicle.

[0012] A third aspect of this application provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to perform the simulation processing method for vehicle ground clearance lines as described in the above embodiments.

[0013] A fourth aspect of this application provides a computer-readable storage medium having a computer program stored thereon, which is executed by a processor to perform the simulation processing method for vehicle ground clearance lines as described in the above embodiments.

[0014] The fifth aspect of this application provides a computer program product, including a computer program or instructions, which, when executed, implement the simulation processing method for vehicle ground clearance lines as described in the above embodiments.

[0015] Therefore, this application has at least the following beneficial effects:

[0016] This application embodiment can obtain the dynamic response parameters of the vehicle under different simulation conditions, reverse the interference position and width between the chassis and the road surface to construct an initial ground clearance line, and further use the interference data output by the target vehicle model to iteratively correct the initial line, thereby obtaining an accurate minimum ground clearance line. This effectively overcomes the limitations of existing technologies that rely solely on static theoretical parameters, and fully integrates multi-dimensional dynamic factors such as suspension motion, vehicle speed, tire stiffness, and road surface morphology, significantly improving the accuracy of ground clearance line prediction. It can provide reliable anti-collision boundary guidance for chassis component layout in the early stages of vehicle development, and greatly reduce the rectification costs and R&D cycle caused by design deviations in the later stages.

[0017] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a flowchart of a simulation processing method for vehicle ground clearance lines according to an embodiment of this application; Figure 2 This is an example diagram of a vehicle multibody dynamics model provided according to an embodiment of this application; Figure 3 This is a schematic diagram of the geometric model provided according to an embodiment of this application; Figure 4 This is a schematic diagram of the step-down time according to an embodiment of this application; Figure 5 This is a schematic diagram of the initial ground clearance line provided according to an embodiment of this application; Figure 6 This is a schematic diagram of the improved ground clearance line provided according to an embodiment of this application; Figure 7 This is a block diagram of a simulation processing device for vehicle ground clearance lines provided according to an embodiment of this application; Figure 8 This is a schematic diagram of the structure of an electronic device provided according to an embodiment of this application. Detailed Implementation

[0019] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0020] The following description, with reference to the accompanying drawings, describes a method, apparatus, device, medium, and program for simulating vehicle ground clearance lines according to embodiments of this application.

[0021] Specifically, Figure 1 This is a flowchart illustrating a simulation processing method for vehicle ground clearance lines provided in an embodiment of this application.

[0022] like Figure 1 As shown, the simulation processing method for the vehicle's ground clearance line includes the following steps: In step S101, the response parameters of the vehicle under different simulation conditions are obtained.

[0023] It is understood that the embodiments of this application can simulate the driving state of a vehicle under different typical working conditions and obtain the corresponding dynamic response parameters, which can realistically restore the actual motion posture and force situation of the vehicle when crossing obstacles or complex road surfaces. This allows key dynamic factors such as suspension bounce, vehicle pitch and tire deformation to be included in the analysis scope, providing a high-fidelity data foundation for subsequent accurate reverse calculation of chassis interference position, and effectively solving the problem of large deviation in ground clearance prediction caused by neglecting driving dynamics characteristics in traditional static calculation methods.

[0024] It should be noted that different simulation conditions refer to various typical virtual test scenarios set up to comprehensively assess vehicle passability. In this solution, it specifically refers to simulating the specific form and movement process of a vehicle crossing obstacles, mainly including the step-up condition (the vehicle drives from a lower level to a higher level step), the step-down condition (the vehicle drives from a higher level to a lower level step), and the step condition with a ramp (the step edge has a transition slope). These conditions aim to reproduce the extreme state of the vehicle under real complex road conditions, where the suspension system experiences violent bouncing and the vehicle body posture undergoes significant pitch changes, in order to capture the dynamic interference that may occur between the chassis and the road surface.

[0025] The preset speed refers to the constant driving speed set in the simulation model when the vehicle passes through the above-mentioned specific simulation conditions. This speed is a key input variable for calculating the vehicle's dynamic response (such as the duration of wheel center displacement). In specific steps of this scheme, two different values, the first preset speed and the second preset speed, are usually involved. By comparing the difference in longitudinal displacement generated by the vehicle passing through the same condition at these two different speeds, the influence of vehicle speed on the interference range between the chassis and the road surface (i.e., the target width) is quantified, thereby more accurately defining the dynamic safety boundary.

[0026] Response parameters typically refer to the dynamic output data generated by the vehicle model in response to road surface excitation under simulation conditions and preset speeds. Specifically, they include: vehicle attitude parameters, suspension system parameters, and geometric interference-derived parameters. Among them, vehicle attitude parameters include vertical displacement, pitch angle, and roll angle; suspension system parameters include wheel center vertical displacement, suspension dynamic deflection, and wheel bounce speed / acceleration; geometric interference-derived parameters include dynamic ground clearance value, interference depth, interference longitudinal coordinates, and swept envelope boundary, without specific limitations.

[0027] In this embodiment of the application, before obtaining the response parameters of the vehicle at the target speed under different simulation conditions, the process includes: establishing a multi-body dynamics model of the whole vehicle including the suspension system, wheels and chassis structure; establishing at least one simulation condition for evaluating the vehicle's passability, the simulation condition including at least one of the following: step-up condition, step-down condition or step condition with slope.

[0028] It is understood that the embodiments of this application can construct a multi-body dynamics model of the whole vehicle covering the suspension system, wheels and chassis structure, and set simulation conditions including typical scenarios such as going up steps, going down steps or steps with slopes. This can realistically reproduce the dynamic response characteristics of the vehicle under complex road conditions from the perspective of physical mechanism, and ensure that the response parameters obtained later fully integrate multi-dimensional factors such as structural elasticity, kinematic relationship and road surface geometry. This lays a high-fidelity simulation foundation for accurately predicting vehicle passability, thereby avoiding the distortion of analysis results caused by model simplification or single working conditions.

[0029] It should be noted that, as Figure 2 As shown, this application uses software to establish a multibody dynamics model of the whole vehicle, including the front and rear suspensions, based on information such as hard points, bushing stiffness, spring stiffness, part center of mass, part mass and moment of inertia in the parameter table.

[0030] This application establishes a multibody dynamics model of the entire vehicle, including the suspension system, wheels, and chassis structure. Based on the vehicle design digital model, the coordinates of the suspension hard points are extracted, and front and rear suspension subsystem models are established separately. In this application, special attention must be paid to the geometric connection relationships of the control arms, steering knuckles, and shock absorbers to ensure that the model can accurately reproduce the motion trajectory of the wheels during vertical bounce. This is because the positions of the ground clearance control points (first and second type control points) at the front and rear of the wheels are directly affected by the suspension kinematic characteristics; accurate topology is the basis for subsequently extracting the dynamic positions of the front / rear control points of the wheels.

[0031] The chassis frame is defined as a flexible body or a rigid body with precise mass inertia parameters. In a key step of this application, a series of virtual detection points need to be discretized and arranged in the lowest risk areas of the chassis (such as the bottom of the battery pack, oil pan, exhaust pipe, and lower edges of the front and rear bumpers). The spatial coordinates of these detection points will serve as real-time monitoring objects, and their vertical displacement data during the simulation process will be directly used to calculate the dynamic ground clearance value. This data source is used to generate the initial ground clearance line covering the longitudinal range of the entire vehicle and to make dynamic corrections.

[0032] The nonlinear stiffness and damping curves of the spring, shock absorber, and buffer block are input, and a high-precision flexible ring tire model is selected. In this application, the selection of the tire model is crucial because the dynamic passability at the "preset speed" depends not only on the vehicle body posture, but also on the tire's envelope deformation capability when crossing a step. A high-precision tire model can simulate the process of the tire tread adhering to the surface of the obstacle, thereby accurately calculating the critical state where the wheel does not interfere but the vehicle chassis interferes, ensuring that the generated ground clearance line conforms to the real physical limits.

[0033] A parameterized virtual test track was established, including steps, slopes, and combined road surfaces of varying heights, to match the different simulation conditions described in this application. Simultaneously, speed or torque constraints were applied to the wheels or drive shafts to achieve constant driving simulation at preset speeds (first preset speed, second preset speed). The aim was to reproduce the transient pitch angle and vertical acceleration generated when a vehicle passes an obstacle at a specific speed; these dynamic responses are the root cause of the failure of the static ground clearance line and the need to generate a dynamic correction line.

[0034] The suspension characteristics are verified through simulation to ensure that the wheel center trajectory is consistent with the design. Dynamic simulation is then performed to solve the problem, outputting the vehicle attitude angles, vertical coordinates of the chassis detection points, and vertical displacement of the wheels in the time domain. In this application, these outputs serve as response parameters. The system uses these parameters to compare the chassis lowest point trajectory at different speeds, identify the location and amount of maximum interference, and then, based on the arc radius algorithm and the front and rear area line segment fusion strategy, correct the static initial ground clearance line to a minimum ground clearance line that reflects the dynamic safety boundary.

[0035] In step S102, the target position and target width where the vehicle chassis interferes with the road surface under different simulation conditions are deduced based on the response parameters.

[0036] It is understood that the embodiments of this application can use the obtained dynamic response parameters to reverse deduce the specific location and width of the interference between the chassis and the road surface, and can transform the transient motion trajectory of the vehicle during driving into a quantified spatial interference boundary, thereby accurately identifying the dynamic collision risk area that is difficult to capture by traditional static analysis, and effectively improving the pertinence and reliability of chassis layout design.

[0037] It should be noted that the target location and target width where the vehicle chassis interferes with the road surface are determined in this application by importing the tire profile and ground line into the modeling software, and establishing four flat plates at the wheel center height on the front and rear sides of the tire, such as... Figure 3 As shown, they are FF, FR, RF, and RR, respectively.

[0038] In this embodiment of the application, the target position where the vehicle chassis interferes with the road surface under the target simulation condition is deduced based on the response parameters, including: identifying the duration corresponding to the wheel center of the front and rear wheels of the vehicle in different simulation conditions from the moment the wheel center is directly above the step to the moment the tire fully contacts the ground; calculating the longitudinal displacement of the front and rear wheels of the vehicle during the landing process based on the duration and a preset speed; and deducing the target position where the vehicle chassis interferes with the road surface under the target simulation condition based on the longitudinal displacement.

[0039] It is understood that the embodiments of this application can accurately identify the duration of the key dynamic interval from the wheel center directly above the step to complete contact with the ground, and calculate the specific longitudinal displacement in combination with the preset speed. This transforms the dynamic response in the time dimension into precise interference coordinates in the spatial dimension, effectively quantifying the actual sweep range of the chassis caused by the suspension movement and body posture changes during the vehicle's crossing of obstacles. This solves the problem that traditional methods cannot determine the specific location of dynamic interference.

[0040] It should be noted that this application simulates reversing down a step at speeds of 3 or 5 km / h, and the simulation results show the time taken for the front and rear tires to descend the step. t f , t r (The time from when the wheel center is directly above the step until the tire fully touches the ground, i.e., the time from when the vertical force on the wheel center begins to decrease and then reaches its maximum after contact with the ground, is used to calculate the longitudinal displacement L of the front and rear wheel centers by multiplying the time of descending the step by the velocity.) f L r ,like Figure 4 As shown.

[0041] In this embodiment of the application, the target width of the vehicle chassis interfering with the road surface under different simulation conditions is deduced based on the response parameters, including: executing the target simulation conditions at a first preset speed and a second preset speed respectively, and obtaining the corresponding first longitudinal displacement and second longitudinal displacement; determining the target width of the vehicle chassis interfering with the road surface under different simulation conditions based on the difference between the first longitudinal displacement and the second longitudinal displacement.

[0042] The first and second preset speeds can be set according to actual needs without specific limitations.

[0043] It is understood that the embodiments of this application can cleverly transform the dynamic response differences caused by speed variables into quantified interference width data by comparing the longitudinal displacement differences generated by the vehicle performing the same simulation condition at different preset speeds. This allows for the accurate capture of the impact of vehicle speed changes on the contact area between the chassis and the road surface, effectively overcoming the deficiency of not being able to fully characterize the dynamic interference space envelope under a single speed condition.

[0044] Specifically, this application calculates the hard point positions of the flat plate at speeds of 3 and 5 km / h, and the difference between the two hard point positions is the width of the flat plate, thereby determining the position and width of the flat plate FF and RF.

[0045] P FF = P 前轮心 -L f (1) P RF = P 后轮心-L r (2) Among them, P 前轮心 P represents the absolute coordinate of the front wheel center in the vehicle's longitudinal coordinate system (X-axis) at the critical moment when the wheel just contacts the edge of the step or completely touches the ground. 后轮心 L represents the absolute coordinates of the rear wheel center in the vehicle's longitudinal coordinate system (X-axis) at the same simulation moment. f L represents the longitudinal dynamic displacement or safety compensation distance in the front wheel area. r P represents the longitudinal dynamic displacement or safety compensation distance in the rear wheel area. FF P represents the coordinates of the rear boundary of the front interference risk region. RF The coordinates are the rear boundary coordinates of the rear interference risk region.

[0046] Simulate driving down the step in the forward direction at 3 or 5 km / h, and determine the position and width of the flat plate FR and RR according to formulas (3) and (4): P FF = P 前轮心+ L f (3) P RF = P 后轮心+ L r (4) Among them, P 前轮心 P represents the absolute coordinate of the front wheel center in the vehicle's longitudinal coordinate system (X-axis) at the critical moment when the wheel just contacts the edge of the step or completely touches the ground. 后轮心 L represents the absolute coordinates of the rear wheel center in the vehicle's longitudinal coordinate system (X-axis) at the same simulation moment. f L represents the longitudinal dynamic displacement or safety compensation distance in the front wheel area. r P represents the longitudinal dynamic displacement or safety compensation distance in the rear wheel area. FF P represents the coordinates of the rear boundary of the front interference risk region. RF The coordinates are the rear boundary coordinates of the rear interference risk region.

[0047] Since the front crossbeam of the front subframe is a key component for evaluation, the FF flat plate is copied and shifted backward (by the width of the flat plate) to obtain flat plate FF1 (considering the risk of collision at the location of the front crossbeam of the subframe).

[0048] Import the aforementioned flatbeds into the established vehicle model, and simulate reversing down a step and driving down a step forward at speeds of 3 and 5 km / h respectively. In the post-processing, calculate the minimum ground clearance of each flatbed during vehicle movement. Subtract the minimum ground clearance from the initial ground clearance of the flatbed to obtain the lowest position of each flatbed (the flatbeds are adjusted both forward and backward, and the flatbeds may not be level after adjustment).

[0049] In step S103, the initial vehicle ground clearance line is determined based on the target position and target width. The initial vehicle ground clearance line is input into the target vehicle model, and the target vehicle model outputs the corresponding interference position and interference amount. The vehicle ground clearance line is corrected based on the interference position and interference amount to generate the minimum ground clearance line of the vehicle.

[0050] It is understood that the embodiments of this application can construct an initial ground clearance line and introduce a target vehicle model for closed-loop verification and iterative correction. The initial line can be finely adjusted by using the specific interference position and interference amount output by the model, thereby effectively eliminating the deviation between theoretical derivation and actual complex working conditions. This ensures that the final generated minimum ground clearance line can truly reflect the vehicle's limit boundary during dynamic driving, significantly improving the accuracy and reliability of chassis anti-collision design.

[0051] In this embodiment, determining the vehicle ground clearance line based on the target location and target width includes: determining multiple ground clearance control points distributed longitudinally along the vehicle based on the target location, wherein the ground clearance control points correspond to the risk locations where the vehicle interferes with the road surface under different simulation conditions; determining the continuous coverage range of the target location in the longitudinal direction of the vehicle based on the target width, and determining the risk area based on the continuous coverage range; constructing ground clearance line segments for different longitudinal regions of the vehicle based on the ground clearance control points, risk areas, and preset ground clearance height constraints; and fusing the ground clearance line segments for different longitudinal regions of the vehicle to generate an initial ground clearance line covering the entire longitudinal range of the vehicle.

[0052] It is understood that the embodiments of this application can combine discrete risk control points with continuous risk coverage ranges and incorporate ground clearance constraints to construct and merge ground clearance line segments in segments, thereby generating a complete initial ground clearance line that includes both key interference extreme points and dynamic sweep continuous areas. This effectively solves the problems of isolated risk points and discontinuous boundaries in traditional methods, and ensures the continuity and integrity of the anti-collision boundary within the longitudinal range of the entire vehicle.

[0053] Specifically, after adjusting the height of the tablet, such as Figure 5 As shown, taking into account the parking condition of a 160mm high step, the front end of the flatbed FF is connected to the hard point at 160mm from the tire, and extended to the expected minimum ground clearance of the whole vehicle at 120mm; the front end of the flatbed FR is connected to the intersection of the minimum ground clearance of 120mm and the wheel, and the front end of the flatbed FR and the rear end of the flatbed FR are connected to the minimum ground clearance of 120mm; the front end of the flatbed RR and the rear end of the flatbed RF are connected in the same way.

[0054] At the center of the vehicle, calculate the radius according to formula (5) so that the circle is tangent to the front and rear wheels and intersects the minimum ground clearance line of 120mm. The resulting arc is the minimum ground clearance of the middle raised part.

[0055] R=L 轴距 / (2×sin(11°))(5) Where R is the minimum ground clearance and L is the wheelbase, which is the horizontal distance between the center of the front wheel and the center of the rear wheel.

[0056] The initial ground clearance line provides poor prediction for the vehicle's center section. Considering the stringent requirements for center section clearance testing on steep inclines and declines, the minimum ground clearance line is improved as follows: Figure 6 As shown. Import the ground clearance line into the vehicle model, perform up and down step ramp conditions, record the interference position and amount with the road surface, and improve the position of the minimum ground clearance line at that point.

[0057] In this embodiment, the method of generating an initial ground clearance line covering the entire longitudinal range of the vehicle by fusing ground clearance line segments from different longitudinal regions of the vehicle includes: extracting a first type of control point located in front of the wheel and a second type of control point located in rear of the wheel from the ground clearance control points, as well as a preset ground clearance height constraint, and constructing ground clearance line segments for the front and rear regions of the vehicle respectively; calculating the radius of the arc based on the vehicle wheelbase and a preset angle, and generating the ground clearance line for the middle region of the vehicle based on the radius of the arc; and fusing the ground clearance line segments from the front and rear regions of the vehicle and the ground clearance line for the middle region of the vehicle to generate an initial ground clearance line covering the entire longitudinal range of the vehicle.

[0058] The preset ground clearance constraint can be set according to actual needs without specific limitations.

[0059] It is understood that the embodiments of this application can construct front and rear area line segments by extracting key control points on the front and rear sides of the wheel, and calculate the arc radius by combining the wheelbase and preset angle to generate the central area curve. Finally, the three geometric features are smoothly integrated to form a continuous initial ground clearance line of the whole vehicle that conforms to the actual structural layout of the vehicle and meets the requirements of dynamic passability. This effectively solves the problems of unsmooth segment data splicing and fuzzy geometric definition of the central transition area, and ensures the integrity and engineering applicability of the longitudinal boundary data of the whole vehicle.

[0060] It should be noted that the first type of control point is located in front of the wheel center (i.e., on the front side of the vehicle's direction of travel). During the dynamic process of the vehicle traversing an obstacle (especially a step or raised surface), it is the specific longitudinal coordinate point where the chassis components achieve maximum vertical approach (or minimum ground clearance) relative to the road surface. When the vehicle drives up a step at a certain speed, the body will pitch up the instant the front wheels contact the step. However, due to inertia and suspension compression, the front of the vehicle will then experience a brief dip or forward movement. At this time, the chassis components located in front of the wheel center will sweep across the edge of the step along an arc. The first type of control point is the point on this scanning trajectory closest to the edge of the step.

[0061] The second type of control point is located behind the wheel center (i.e., behind the vehicle's direction of travel). During the dynamic process of a vehicle traversing an obstacle (especially descending a step or uneven surface), it is a specific longitudinal coordinate point where the chassis components experience the maximum vertical approach relative to the road surface. When the vehicle descends a step at a certain speed, the body will experience a violent nose-dive at the moment the rear wheels reach the edge of the step, and the rear suspension may undergo a transient process from extension to compression. At this time, the chassis components located behind the wheel center will dig downwards, making them highly susceptible to interference with the edge of the step. The second type of control point is the location with the highest risk during this dynamic process.

[0062] The simulation processing method for vehicle ground clearance line proposed in this application obtains the dynamic response parameters of the vehicle under different simulation conditions, reversely calculates the interference position and width between the chassis and the road surface to construct the initial ground clearance line, and further uses the interference data output by the target vehicle model to iteratively correct the initial line, thereby obtaining the accurate minimum ground clearance line. This effectively overcomes the limitation of existing technologies that rely solely on static theoretical parameters, fully integrates multi-dimensional dynamic factors such as suspension motion, vehicle speed, tire stiffness, and road surface morphology, significantly improves the accuracy of ground clearance line prediction, and can provide reliable anti-collision boundary guidance for chassis component layout in the early stages of vehicle development, greatly reducing the rectification costs and R&D cycle caused by design deviations in the later stages.

[0063] The following will combine Figures 2-6 The simulation processing method for the vehicle ground clearance line in this application is described in detail below: Step 1: Based on the information in the parameter table, such as hard points, bushing stiffness, spring stiffness, part center of mass, part mass, and moment of inertia, use modeling software to establish a multibody dynamics model of the entire vehicle, including the front and rear suspensions. Figure 2 As shown.

[0064] Step 2: Based on simulation and testing experience, it can be determined that the most stringent conditions for assessing vehicle passability are ascending and descending steps, with the key testing areas being the front and rear sides of the wheels. Therefore, in the modeling software, import the tire contour lines and ground lines, and at the wheel center height, create four flat surfaces on the front and rear sides of the tire, as shown below. Figure 3 As shown, they are FF, FR, RF, and RR, respectively.

[0065] The length of each plate is determined as follows: (1) Establish a model of the stepped pavement. The step height is generally 120~140mm. (2) Simulate reversing down a step at 3 or 5 km / h, and read the time taken for the front and rear tires to go down the step in the simulation results. t f , t r(The time from when the wheel center is directly above the step until the tire fully touches the ground, i.e., the time from when the vertical force on the wheel center begins to decrease, then reaches its maximum after contact with the ground, such as...) Figure 4 (As shown).

[0066] (3) Calculate the longitudinal displacement L of the front and rear wheels by multiplying the time of going down the step by the speed. f L r The positions of the hard points on the plate are given in formulas (1) and (2). The positions of the hard points on the plate at speeds of 3 and 5 km / h are calculated respectively. The difference between the two hard point positions is the width of the plate. Thus, the positions and widths of the plates FF and RF can be determined.

[0067] P FF = P 前轮心 -L f (1) P RF = P 后轮心 -L r (2) Among them, P 前轮心 P represents the absolute coordinate of the front wheel center in the vehicle's longitudinal coordinate system (X-axis) at the critical moment when the wheel just contacts the edge of the step or completely touches the ground. 后轮心 L represents the absolute coordinates of the rear wheel center in the vehicle's longitudinal coordinate system (X-axis) at the same simulation moment. f L represents the longitudinal dynamic displacement or safety compensation distance in the front wheel area. r P represents the longitudinal dynamic displacement or safety compensation distance in the rear wheel area. FF P represents the coordinates of the rear boundary of the front interference risk region. RF The coordinates are the rear boundary coordinates of the rear interference risk region.

[0068] (4) Simulate driving down the step in the forward direction at 3 or 5 km / h, and determine the position and width of the flat plate FR and RR according to formulas (3) and (4): P FF = P 前轮心+ L f (3) P RF = P 后轮心+ L r (4) Among them, P 前轮心 P represents the absolute coordinate of the front wheel center in the vehicle's longitudinal coordinate system (X-axis) at the critical moment when the wheel just contacts the edge of the step or completely touches the ground. 后轮心 L represents the absolute coordinates of the rear wheel center in the vehicle's longitudinal coordinate system (X-axis) at the same simulation moment. f L represents the longitudinal dynamic displacement or safety compensation distance in the front wheel area. r P represents the longitudinal dynamic displacement or safety compensation distance in the rear wheel area.FF P represents the coordinates of the rear boundary of the front interference risk region. RF The coordinates are the rear boundary coordinates of the rear interference risk region.

[0069] (5) The front crossbeam of the front subframe is a key part to be tested. Therefore, the FF flat plate is copied and moved backward (by the width of the flat plate) to obtain the flat plate FF1 (considering the risk of collision at the position of the front crossbeam of the subframe).

[0070] Step 3: Vertical position adjustment of the flatbed: Import the above flatbed into the vehicle model established in Step 1, and perform reversing down the step and driving down the step forward at 3 and 5 km / h respectively. Calculate the minimum ground clearance of each flatbed during vehicle movement in the post-processing. Subtract the minimum ground clearance from the initial ground clearance of the flatbed to obtain the lowest position of each flatbed (adjust both the front and back of the flatbed. The flatbed may not be level after adjustment).

[0071] Step 4: Initial ground clearance line: After adjusting the plate height, as shown... Figure 5 As shown, taking into account the parking condition of a 160mm high step, the front end of the flatbed FF is connected to the hard point at 160mm from the tire, and extended to the expected minimum ground clearance of the whole vehicle at 120mm; the front end of the flatbed FR is connected to the intersection of the minimum ground clearance of 120mm and the wheel, and the front end of the flatbed FR and the rear end of the flatbed FR are connected to the minimum ground clearance of 120mm; the front end of the flatbed RR and the rear end of the flatbed RF are connected in the same way.

[0072] At the center of the vehicle, calculate the radius according to formula (5) so that the circle is tangent to the front and rear wheels and intersects the minimum ground clearance line of 120mm. The resulting arc is the minimum ground clearance of the middle raised part.

[0073] R=L 轴距 / (2×sin(11°))(5) Where R is the minimum ground clearance, and L 轴距 This refers to the vehicle's wheelbase, which is the horizontal distance between the centers of the front and rear wheels.

[0074] Step 5: The initial ground clearance line provides poor prediction for the vehicle's center. Considering the stringent uphill and downhill ramp conditions required for vehicle center clearance testing, the minimum ground clearance line is improved as follows: Figure 6 As shown. Import the ground clearance line obtained in step 4 into the vehicle model, perform up and down step ramp conditions, record the interference position and amount with the road surface, and improve the position of the minimum ground clearance line at that point.

[0075] Step 6: Minimum Ground Clearance Line Verification: The conditions for ascending and descending steps, including steps with inclines, place stringent demands on the vehicle's passability. The given minimum ground clearance line is conservative, and in actual vehicle layout, it's difficult to ensure that chassis components are completely free from impacts. The improved ground clearance line basically meets the vehicle's passability requirements. Importing it into the vehicle model, we completed simulations of all passability conditions, observing whether any individual road surfaces still interfered. If so, we adjusted the ground clearance line height at the interference locations.

[0076] In summary, this application constructs ground clearance lines for the front and rear regions by extracting dynamic risk control points on the front and rear sides of the wheels, and combines these with a central arc transition line calculated based on the wheelbase and preset approach angle to generate an initial ground clearance line covering the longitudinal range of the entire vehicle. This initial line is then input into the vehicle model for dynamic simulation, and the initial line is iteratively corrected based on the output interference position and amount. Finally, a minimum ground clearance line is generated that accurately covers the dynamic sweep risk caused by attitude changes (such as pitch and suspension compression) under complex conditions such as driving up / down steps. This effectively solves the problem that traditional static design cannot identify dynamic bottoming hazards, significantly improving the accuracy, safety, and development efficiency of vehicle chassis passability design.

[0077] Next, the simulation processing device for vehicle ground clearance lines proposed according to the embodiments of this application is described with reference to the accompanying drawings.

[0078] Figure 7 This is a block diagram of a simulation processing device for vehicle ground clearance lines according to an embodiment of this application.

[0079] like Figure 7 As shown, the simulation processing device 10 for the vehicle ground clearance line includes: an acquisition module 100, a reverse calculation module 200, and a correction module 300.

[0080] The acquisition module 100 is used to acquire the response parameters of the vehicle under different simulation conditions; the reverse calculation module 200 is used to reverse calculate the target position and target width of the vehicle chassis interfering with the road surface under different simulation conditions based on the response parameters; the correction module 300 is used to determine the initial vehicle ground clearance line based on the target position and target width, input the initial vehicle ground clearance line into the target vehicle model, the target vehicle model outputs the corresponding interference position and interference amount, and correct the vehicle ground clearance line based on the interference position and interference amount to generate the minimum ground clearance line of the vehicle.

[0081] The simulation processing device for vehicle ground clearance line proposed in this application obtains the dynamic response parameters of the vehicle under different simulation conditions, reverse-engineers the interference position and width between the chassis and the road surface to construct an initial ground clearance line, and further uses the interference data output by the target vehicle model to iteratively correct the initial line, thereby obtaining an accurate minimum ground clearance line. This effectively overcomes the limitations of existing technologies that rely solely on static theoretical parameters, fully integrates multi-dimensional dynamic factors such as suspension motion, vehicle speed, tire stiffness, and road surface morphology, significantly improves the accuracy of ground clearance line prediction, and can provide reliable anti-collision boundary guidance for chassis component layout in the early stages of vehicle development, greatly reducing the rectification costs and R&D cycle caused by design deviations in the later stages.

[0082] Figure 8 A schematic diagram of the structure of an electronic device provided in an embodiment of this application. The electronic device may include: The memory 801, the processor 802, and the computer program stored on the memory 801 and capable of running on the processor 802.

[0083] When the processor 802 executes the program, it implements the simulation processing method for the vehicle ground clearance line provided in the above embodiments.

[0084] Furthermore, electronic devices also include: Communication interface 803 is used for communication between memory 801 and processor 802.

[0085] The memory 801 is used to store computer programs that can run on the processor 802.

[0086] The memory 801 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0087] If the memory 801, processor 802, and communication interface 803 are implemented independently, then the communication interface 803, memory 801, and processor 802 can be interconnected via a bus to complete communication between them. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized into address buses, data buses, control buses, etc. For ease of representation, Figure 8 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0088] Optionally, in a specific implementation, if the memory 801, processor 802, and communication interface 803 are integrated on a single chip, then the memory 801, processor 802, and communication interface 803 can communicate with each other through an internal interface.

[0089] The processor 802 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application.

[0090] This application also provides a computer-readable storage medium storing a computer program or instructions thereon, which, when executed by a processor, implements the above-described simulation processing method for vehicle ground clearance lines.

[0091] This application also provides a computer program product, including a computer program or instructions, which, when executed, implement the above-described simulation processing method for vehicle ground clearance lines.

[0092] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0093] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0094] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or N executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0095] It should be understood that the various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or more of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0096] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

Claims

1. A simulation processing method for vehicle ground clearance lines, characterized in that, Includes the following steps: Obtain the vehicle's response parameters under different simulation conditions; Based on the response parameters, the target position and target width where the vehicle chassis interferes with the road surface under different simulation conditions are deduced. The initial vehicle ground clearance line is determined based on the target position and target width. The initial vehicle ground clearance line is input into the target vehicle model. The target vehicle model outputs the corresponding interference position and interference amount. The vehicle ground clearance line is corrected based on the interference position and interference amount to generate the minimum ground clearance line of the vehicle.

2. The simulation processing method for vehicle ground clearance lines according to claim 1, characterized in that, The step of reversing the target position where the vehicle chassis interferes with the road surface under the target simulation condition based on the response parameters includes: Identify the time intervals in the response parameters of the front and rear wheel centers of the vehicle from the moment the wheel center is directly above the step to the moment the tires fully contact the ground under different simulation conditions. Calculate the longitudinal displacement of the vehicle's front and rear wheels during the landing process based on the duration and preset speed; Based on the longitudinal displacement, the target position where the vehicle chassis interferes with the road surface under the target simulation condition is deduced.

3. The simulation processing method for vehicle ground clearance lines according to claim 2, characterized in that, The step of back-calculating the target width of the vehicle chassis interfering with the road surface under different simulation conditions based on the response parameters includes: The target simulation condition is executed at a first preset speed and a second preset speed respectively, and the corresponding first longitudinal displacement and second longitudinal displacement are obtained. The target width at which the vehicle chassis interferes with the road surface under different simulation conditions is determined based on the difference between the first longitudinal displacement and the second longitudinal displacement.

4. The simulation processing method for vehicle ground clearance lines according to claim 3, characterized in that, Determining the vehicle ground clearance line based on the target position and target width includes: Based on the target location, multiple ground clearance control points are determined along the longitudinal direction of the vehicle, wherein the ground clearance control points correspond to the risk locations where the vehicle may interfere with the road surface under different simulation conditions; The continuous coverage area of ​​the target location along the longitudinal direction of the vehicle is determined based on the target width, and the risk area is determined based on the continuous coverage area. Based on the ground clearance control point, the risk area, and the preset ground clearance height constraint, ground clearance line segments are constructed for different longitudinal regions of the vehicle. The ground clearance lines of different longitudinal regions of the vehicle are merged to generate an initial ground clearance line covering the entire longitudinal range of the vehicle.

5. The simulation processing method for vehicle ground clearance lines according to claim 4, characterized in that, The process of merging ground clearance segments from different longitudinal regions of the vehicle to generate an initial ground clearance line covering the entire longitudinal range of the vehicle includes: Extract the first type of control points located in front of the wheel and the second type of control points located behind the wheel from the ground clearance control points, as well as the preset ground clearance height constraint, and construct the ground clearance line segments for the front and rear areas of the vehicle respectively; The radius of the arc is calculated based on the vehicle wheelbase and a preset angle, and the ground clearance line of the central area of ​​the vehicle is generated based on the radius of the arc. The ground clearance lines of the front and rear areas of the vehicle and the ground clearance line of the middle area of ​​the vehicle are merged to generate an initial ground clearance line covering the longitudinal range of the entire vehicle.

6. The simulation processing method for vehicle ground clearance lines according to claim 1, characterized in that, Before obtaining the vehicle's response parameters under different simulation conditions, the process includes: Establish a multibody dynamics model of the entire vehicle, including the suspension system, wheels, and chassis structure; Establish at least one simulation condition for assessing vehicle passability, the simulation condition including at least one of an up-step condition, a down-step condition, or a step condition with a ramp.

7. A simulation processing device for vehicle ground clearance lines, characterized in that, include: The acquisition module is used to acquire the response parameters of the vehicle under different simulation conditions; The reverse-engineering module is used to reverse-engineer the target position and target width of the vehicle chassis interfering with the road surface under different simulation conditions based on the response parameters; The correction module is used to determine the initial vehicle ground clearance line based on the target position and target width, input the initial vehicle ground clearance line into the target vehicle model, the target vehicle model outputs the corresponding interference position and interference amount, and correct the vehicle ground clearance line based on the interference position and interference amount to generate the minimum ground clearance line of the vehicle.

8. An electronic device, characterized in that, include: A memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the program to implement the simulation processing method for vehicle ground clearance lines as described in any one of claims 1-6.

9. A computer-readable storage medium having a computer program or instructions stored thereon, characterized in that, When the computer program or instructions are executed by the processor, they are used to implement the simulation processing method for vehicle ground clearance lines as described in any one of claims 1-6.

10. A computer program product, comprising a computer program or instructions, characterized in that, When the computer program or instructions are executed, they implement the simulation processing method for vehicle ground clearance lines as described in any one of claims 1-6.

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