Method for analyzing whole vehicle impact performance, electronic device, and storage medium

Abstract

The application provides a whole vehicle impact performance analysis method, an electronic device and a storage medium, and belongs to the technical field of vehicle dynamics simulation. The method comprises the following steps: establishing a whole vehicle dynamics model, the dynamics model at least representing the longitudinal motion of the vehicle, the vertical and pitching motion of the sprung mass, and the vertical motion of the front and rear wheels; obtaining basic state parameters and road excitation data in the no-load state of the whole vehicle; configuring the dynamics model based on the basic state parameters; determining each force acting on the dynamics model according to the vehicle driving condition and the road excitation data, the each force at least comprising a suspension spring force, a damping force, a friction force and an anti-pitching force; establishing a whole vehicle dynamics equation set based on the dynamics model and the each force; and solving the dynamics equation set by using a numerical calculation method to obtain a dynamic response representing the impact performance of the whole vehicle. The method can quantitatively predict and analyze the impact performance in the whole vehicle conceptual design stage, thereby shortening the development cycle and reducing the development cost.

Description

Technical Field

[0001] This application belongs to the field of vehicle dynamics simulation technology, specifically relating to an analysis method for the impact performance of a whole vehicle, electronic equipment, and storage medium. Background Technology

[0002] When a car traverses uneven or potholed road surfaces, it experiences significant impacts, leading to a poor passenger experience and affecting the overall ride quality. Currently, OEMs primarily address this issue during the post-production testing phase, where engineers optimize parameters such as spring stiffness and bumper hardness based on experience. This method has significant drawbacks: 1) The development time is long and does not meet the current development pace. Debugging engineers rely on experience to select matching stiffness, which is highly dependent on engineering experience and cannot quickly lock in a solution. They can only keep trying various matching solutions, resulting in long development time. 2) During the design phase, quantitative data cannot be used to evaluate the matching results; the evaluation relies entirely on subjective feelings during later debugging. 3) If the impact of the vehicle passing over bumps or potholes is not systematically considered in the early stages of the design, the problem of poor impact perception cannot be completely solved in the later debugging, which leads to extensive design changes and ultimately has a great impact on the development time, cost and quality of the vehicle.

[0003] Therefore, there is an urgent need for a method that can quantitatively predict and analyze impact performance during the whole vehicle concept design stage, in order to shorten the development cycle and reduce development costs. Summary of the Invention

[0004] The purpose of this application is to solve the problems existing in the prior art and provide a method, electronic device and storage medium for analyzing the impact performance of a vehicle, so as to enable quantitative prediction and analysis of impact performance in the vehicle concept design stage, shorten the development cycle and reduce development costs.

[0005] This application is achieved through the following technical solution: The first aspect of this application provides a method for analyzing the impact performance of a whole vehicle, the method comprising: Establish a dynamic model of the whole vehicle, which at least characterizes the longitudinal motion of the vehicle, the vertical and pitch motion of the sprung mass, and the vertical motion of the front and rear wheels. Acquire the basic state parameters and road excitation data of the vehicle under no-load conditions; Based on the aforementioned basic state parameters, the dynamic model is configured such that the inertial parameters and attitude of the dynamic model correspond to the target load state. Based on the vehicle driving conditions and the road excitation data, the forces acting on the dynamic model are determined. The forces include at least the suspension spring force, damping force, friction force, and anti-pitch force. Based on the aforementioned dynamic model and the aforementioned forces, a set of vehicle dynamic equations is established; The dynamic equations are solved using numerical calculation methods to obtain the dynamic response characterizing the impact performance of the vehicle.

[0006] Preferably, the dynamic model is a lumped mass model.

[0007] Preferably, the lumped mass model is a five-degree-of-freedom model, wherein the five degrees of freedom include: the overall longitudinal displacement of the vehicle, the vertical displacement of the sprung mass, the pitch angle displacement of the sprung mass, the vertical displacement of the unsprung mass of the front wheel, and the vertical displacement of the unsprung mass of the rear wheel.

[0008] Preferably, the dynamic model is configured based on the basic state parameters, including: Based on the basic state parameters, the vehicle inertial parameters and attitude parameters after adding the effective load are calculated, and the vehicle inertial parameters and attitude parameters are set as the initial physical conditions for the dynamic model to perform dynamic response calculation.

[0009] Preferably, the road surface excitation data is two-dimensional planar coordinate data, including the vehicle's longitudinal position and its corresponding road surface vertical height, and the sampling density in areas where the road surface curvature change is greater than a preset threshold is greater than the sampling density in areas where the road surface curvature change is less than or equal to the preset threshold.

[0010] Preferably, the forces in each direction are determined by corresponding force functions, which are constructed based on at least one of the K&C data of the vehicle suspension and tires and component test data.

[0011] Preferably, the anti-pitch force includes anti-nose force and anti-lift force generated by the suspension geometry.

[0012] Preferably, the dynamic response includes at least one of displacement, velocity, acceleration, and stress of the whole vehicle and key components.

[0013] A second aspect of this application provides an electronic device including a memory and a processor, wherein the memory stores a computer program executed by the processor, the computer program, when executed by the processor, causes a device equipped with the processor to perform the whole vehicle impact performance analysis method as described in any of the preceding claims. A third aspect of this application provides a storage medium storing a computer program that runs on a computer and, when running, causes the computer to perform the whole vehicle impact performance analysis method as described in any of the preceding claims.

[0014] Compared with the prior art, the beneficial effects of this application are: 1. Shorten development cycle and reduce development costs: By combining configurable dynamic models and dynamic equations, impact performance can be predicted and analyzed during the whole vehicle concept design stage, guiding the selection and design of elastic elements, reducing reliance on actual vehicle debugging and experience trial and error, and avoiding the need for engineers to select matching stiffness based on their experience during actual vehicle debugging.

[0015] 2. Achieve quantitative design: Provide quantitative data on dynamic response during the design phase as an evaluation basis to address the significant impact on vehicles when passing over characteristic road surfaces such as bumps or potholes, thereby achieving objective and precise optimization of ride quality and improving the smoothness and ride quality of the entire vehicle when passing over characteristic road surfaces. Attached Figure Description

[0016] The above and other objects, features, and advantages of this application will become more apparent from the more detailed description of the embodiments of this application in conjunction with the accompanying drawings. The accompanying drawings are used to provide a further understanding of the embodiments of this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof.

[0017] Figure 1 A flowchart illustrating a method for analyzing the impact performance of a vehicle, provided in an embodiment of this application; Figure 2 A flowchart illustrating another method for analyzing the impact performance of a vehicle as provided in this application embodiment; Figure 3 This is a schematic diagram of the mass distribution and geometric parameters of a vehicle under unloaded conditions in an embodiment of the present invention; Figure 4 This is a diagram showing the degree of freedom definition of the five-degree-of-freedom lumped mass model in an embodiment of the present invention; Figure 5 This is a schematic diagram of the mass distribution and geometric parameters of the target load state in an embodiment of the present invention; Figure 6 This is a schematic diagram of the external input and internal forces of the 5-DOF dynamics model of the vehicle under no-load conditions in an embodiment of the present invention; Figure 7 This is an analytical diagram of wheel load in an embodiment of the present invention; Figure 8 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this application more apparent, exemplary embodiments according to this application will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments of this application. It should be understood that this application is not limited to the exemplary embodiments described herein. Based on the embodiments of this application described herein, all other embodiments obtained by those skilled in the art without inventive effort should fall within the protection scope of this application.

[0019] To address the problem that existing methods cannot use quantitative data to evaluate matching results during the design phase, thus extending the development cycle and increasing development costs, this application proposes a method for analyzing the impact performance of a vehicle. This method enables quantitative prediction and analysis of impact performance during the vehicle concept design phase, shortening the development cycle and reducing development costs. The following is a further detailed description of this application with reference to the accompanying drawings.

[0020] To facilitate understanding of this application, a detailed description of a method for analyzing the impact performance of a vehicle, as disclosed in the embodiments of this application, will be provided first. The execution entity of this method is generally a computer device with certain computing capabilities. This computer device may include, for example, a terminal device, a server, or other processing devices. The terminal device may be a user equipment (UE), a mobile device, a user terminal, etc. In some possible implementations, this method for analyzing the impact performance of a vehicle can be implemented by a processor calling computer-readable instructions stored in memory.

[0021] Figure 1 A flowchart illustrating a method for analyzing the impact performance of a vehicle, as provided in this application embodiment, is shown below. Figure 1 This application describes a method for analyzing the impact performance of a vehicle, as provided in an embodiment.

[0022] like Figure 1 As shown, the method for analyzing the impact performance of a vehicle in this application includes at least the following steps S100 to S600.

[0023] Step S100: Establish a dynamic model of the whole vehicle. The dynamic model shall at least characterize the longitudinal motion of the vehicle, the vertical and pitch motion of the sprung mass, and the vertical motion of the front and rear wheels.

[0024] In this context, the dynamic model refers to a set of mathematical equations or computational framework used to describe the motion of a vehicle system. In this application, it refers to a mathematical model capable of simulating key motions of a vehicle under impact conditions, such as longitudinal, vertical, pitch, and wheel hop, and is the core tool for analysis.

[0025] Specifically, the dynamic model is a lumped mass model.

[0026] The lumped mass model is a simplified physical modeling method for vehicle dynamics analysis. Its core idea is to represent the distributed mass, inertia, and stiffness characteristics of a vehicle system as a finite number of key mass points (lumped masses) and massless elastic / damped elements connecting these mass points. Each "lumped mass" represents a component or group of components in the vehicle with significant inertial effects (such as sprung mass or unsprung mass), whose motion is described by Newton's second law. This model achieves a good balance between computational accuracy and model complexity, avoiding the drawbacks of complex models such as difficult parameter preparation and long computation times. By focusing on the core dynamic aspects of impact conditions and relying on high-fidelity K&C data for precise simplification, it successfully achieves efficient, reliable, and quantitative prediction of impact performance during the design phase.

[0027] In this application, the term K&C data is an abbreviation for suspension system kinematics and compliance test data. This data is acquired through a dedicated K&C test bench and can accurately describe the geometric motion and elastic deformation characteristics of the suspension system under controlled wheel motion and external forces. K&C data is the fundamental input for constructing key force functions such as suspension spring force, friction force, and anti-pitch force in this application.

[0028] Step S200: Obtain the basic state parameters and road excitation data of the vehicle under no-load conditions.

[0029] Among them, the basic state parameters refer to a series of inherent physical parameters of a vehicle under a known and determined reference state (usually an unloaded state), including but not limited to mass, geometric dimensions (such as wheelbase), inertial parameters (such as moment of inertia), etc.

[0030] The road surface excitation data is two-dimensional coordinate data describing the profile of the vehicle's centerline trajectory, including the vehicle's longitudinal position and its corresponding vertical height on the road surface. Preferably, a non-uniform sampling strategy can be used to generate this data: in areas where the road surface profile curvature is greater than a preset threshold (where the geometry changes drastically), such as the top of a protrusion or the edge of a pothole, a higher sampling density is used; in areas with a gentle profile, i.e., where the road surface curvature change is less than or equal to the preset threshold, a lower sampling density is used. This effectively controls the total amount of data while ensuring that key excitation features are accurately captured, thereby improving the simulation solution speed to meet different user scenarios.

[0031] Step S300: Based on the basic state parameters, configure the dynamic model so that the inertial parameters and attitude of the dynamic model correspond to the target load state.

[0032] In this context, "configuration" refers to the operation of setting or assigning values ​​to the intrinsic parameters of the dynamic model, such as mass and inertia, and initial states, such as vehicle pitch angle and height, according to target requirements and, in this application, the target load state. The target load state refers to the specific load condition (e.g., fully loaded with 5 people and luggage) that the vehicle is expected to experience during analysis. It is relative to the basic state and represents the target operating condition that the model needs to simulate.

[0033] Step S400: Based on the vehicle driving conditions and the road excitation data, determine the forces acting on the dynamic model. The forces include at least the suspension spring force, damping force, friction force, and anti-pitch force.

[0034] Here, anisotropic forces refer to the various internal and external forces acting on the dynamic model during vehicle motion. In this application, anisotropic forces include at least: suspension spring force (elastic restoring force), damping force (shock absorber dissipation force), friction force (internal friction of the suspension system), and anti-pitch force (geometric force resisting vehicle nodding or lifting). The nonlinear characteristics of these forces are crucial to impact accuracy.

[0035] Step S500: Based on the dynamic model and the forces in each direction, establish the vehicle dynamic equation set.

[0036] The vehicle dynamics equations refer to a set of coupled mathematical equations that fully describe the dynamic behavior of a vehicle system, established based on Newton's laws of motion (such as the relationship between force and motion), combined with the aforementioned dynamic model and anisotropic forces. Solving this set of equations yields the system's response.

[0037] Step S600: Solve the dynamic equations using numerical calculation methods to obtain the dynamic response characterizing the impact performance of the whole vehicle.

[0038] Numerical computation methods refer to the collective term for computer algorithms used to solve complex mathematical equations (such as nonlinear dynamic equations) that cannot be solved analytically, including various numerical integration and finite difference methods. Dynamic response refers to the output of physical quantities characterizing the dynamic behavior of a vehicle system, obtained by solving equations under road excitation and driving conditions. It typically includes data on the time-varying changes of displacement, velocity, acceleration, force / stress, etc., and is used to directly evaluate impact performance.

[0039] This application provides an analysis method for the impact performance of general-purpose vehicles. By combining a configurable dynamic model with precise force functions, the impact performance can be predicted and analyzed during the vehicle concept design stage, guiding the selection and design of elastic elements, reducing reliance on actual vehicle debugging and trial and error based on experience, and avoiding the need for engineers to select matching stiffness based on their experience during actual vehicle debugging. This achieves high-precision and quantitative simulation of the impact performance of the whole vehicle under various load conditions in the early stage of design, thereby effectively overcoming the drawbacks of traditional development models such as long cycle, high cost, and reliance on experience, and significantly improving the design quality and development efficiency of chassis systems.

[0040] Next, refer to Figures 2 to 7 This application describes another method for analyzing the impact performance of a vehicle, as provided in its embodiments. Figures 3 to 7 The gray or green outline in the front center compartment is a simplified diagram of the powertrain (engine and transmission), used to identify the powertrain's location within the vehicle and provide a positional reference for determining the initial center of gravity and moment of inertia parameters. The arrows in the diagram are categorized as follows: Coordinate system arrow: Defines the positive direction of the model's reference coordinate system; Displacement / motion arrows: Indicate the positive displacement and positive motion direction for each degree of freedom; Force and inertial force arrows: indicate the direction of action of spring force, damping force, friction force, anti-plunging / anti-lifting force, and inertial force; Circular arrow: Indicates the direction of rotation of the resultant torque, inertial torque, and wheel angular acceleration; External excitation arrows: indicate the input direction of vertical excitation from the road surface and longitudinal force from the tire.

[0041] All arrows are only used to visually indicate the direction of action of each physical quantity and do not change the core technical solution of the dynamic model of this application.

[0042] like Figure 2 As shown, the method for analyzing the impact performance of a vehicle provided in this embodiment includes the following steps: S1. Establish a five-degree-of-freedom dynamic model of the entire vehicle.

[0043] like Figure 3 As shown, the vehicle's suspension system includes front and rear suspension springs and front and rear shock absorbers, and the forces it experiences include suspension friction and suspension side anti-diving impact force; the tire system includes front and rear tire springs and front and rear tire dampers, and the forces it experiences include tire side anti-diving impact force. Points A and B are the connection and mounting points between the front and rear suspensions and the vehicle body. Figure 3 A planar coordinate system is established with the road surface as the reference. The x-axis represents the vehicle's direction of travel (same as the vehicle speed V), and the z-axis is perpendicular to the road surface and pointing upwards. The front wheel contact point P... F Rear wheel ground contact point P RThe tire-road action reference is used, with the vehicle's unloaded center of gravity as the reference for rotational inertia and force analysis. Hpoint (P, Q) refers to the H-points (human hip points) of the front and rear seats, used to define the occupant posture and load reference. Figure 3 The geometric and mass parameters are shown in Table 1.

[0044] Table 1

[0045] Z rF (t) For the road surface input in the vertical direction of the front wheels, with ( x, z Input the distance coordinates. Z rR (t) For the road surface input in the vertical direction of the rear wheels, with ( x, z Input the distance coordinates. F xpF ( t ), F xpR ( t These are the longitudinal resultant forces of the front and rear tires, respectively, which are input as acceleration. The front and rear distribution is determined based on the braking curve and the characteristics of vehicles such as front-wheel drive, rear-wheel drive, and 4WD.

[0046] In this step, a dynamic model is established to characterize the key motions of the vehicle under impact conditions. This model is a five-degree-of-freedom, left-right symmetrical pitch model. For example... Figure 4 As shown, the vehicle's native coordinate system (X) V Z V The origin (O) is defined as the point where a perpendicular line is drawn from the center of mass of the spring under the condition of analytical mass (empty load + passenger + carry-on baggage). The intersection of this line with the road surface is the origin. V The red arrows indicate the five degrees of freedom: longitudinal displacement of the vehicle as a whole in the direction of travel. X v Vertical displacement of the spring mass Z S Sprung mass pitch angle displacement ψ S Vertical displacement of the unsprung mass of the front wheel Z uF and the vertical displacement Z of the unsprung mass of the rear wheel. uR .

[0047] Spring-loaded center of mass C bs Compared with the sprung mass of the simulated vehicle containing the effective load M bs Pitch moment of inertia I bs_YYThe vehicle body inertial characteristics are jointly defined, providing basic parameters for the vertical and pitch dynamics analysis of the model.

[0048] ψ 0 represents the initial pitch angle of the vehicle in its unloaded static equilibrium state, characterizing the inherent attitude of the vehicle body relative to a horizontal reference, and is the dynamic pitch angle. ψ s The reference zero point; to establish the vehicle pitch motion equation, based on the initial pitch angle of the vehicle. ψ 0 and dynamic pitch angle ψ s The wheelbase of the front and rear suspension mounting points L v Longitudinal distance from the sprung center of gravity to the front and rear suspensions L bsF , L bsR Projecting the distance in the direction of vehicle travel yields the horizontal projection distance. L v cos(ψ s +ψ 0 ) , L bsF cos(ψs+ψ 0 ) , L bsR cos(ψ s +ψ 0 ) It is used to calculate the pitching moment of the suspension force and tire force on the vehicle's center of gravity.

[0049] The dynamic model in this embodiment comprehensively considers the internal friction of the suspension, which has a significant impact on ride comfort, as well as the anti-dive and anti-lift-off mechanical effects generated by the suspension geometry. This allows for precise analysis and optimization of the vehicle's dynamic performance under any driving conditions, including constant speed, acceleration, and deceleration, and when traversing complex coupled conditions such as road bumps or potholes. The model is simple in structure, computationally efficient, and effectively captures the main body and wheel movements under impact excitation.

[0050] S2. Obtain the basic state parameters and road excitation data of the vehicle under no-load conditions.

[0051] Basic state parameters refer to a series of inherent physical parameters of the vehicle under unloaded conditions (i.e., no occupants, no luggage, and fuel level at the specified value, as per factory baseline). The distances between parts are based on the front axle, and the initial pitch angle is zero under unloaded conditions. Specific parameters should include at least the information shown in Table 2, which is the input data table. Table 2

[0052] The road surface excitation data consists of two-dimensional planar coordinate data (X, Z) describing the road surface profile, where X represents the vehicle's longitudinal position and Z represents the vertical height at the corresponding position. To balance computational accuracy and efficiency, an adaptive sampling strategy can be adopted: denser sampling points are used in areas with high road surface curvature (drastic changes), while sparser sampling points are used in flat areas.

[0053] S3. Configure the dynamic model to the target load state.

[0054] To simulate different load conditions, the model needs to be configured from an unloaded baseline state to the actual target load state to be analyzed, such as a fully loaded state. Figure 5 As shown, the red dashed line represents the initial rotation trajectory caused by the payload in the prepared state, and the initial pitch angle change caused by the payload is... ψ s0 This is used to characterize the vehicle body attitude deviation caused by load. The effective load includes the front occupant load (front passenger mass). M pF , Z hpF (Front row passenger mass height), rear row passenger load (rear row passenger mass) M pR , Z hpR For rear passenger mass height) and luggage load (luggage weight) M T , Z T Let the height be the mass of the luggage compartment, and the positions of the seat H (P, Q) and the luggage T be the load application points. The longitudinal horizontal distance of the luggage T relative to the front suspension point A is... -X T The longitudinal horizontal distance between point P and the front suspension point A is -X pF The longitudinal horizontal distance between point Q and the front suspension point A is -X pR (The negative sign indicates that it is located behind point A).

[0055] The solid red dot represents the sprung center of mass C of the simulated vehicle. ss That is, under simulated conditions containing effective load, the vertical height of the center of gravity of the vehicle body (sprung load) is... H bs_CG The simulated vehicle's sprung mass is M bs The pitch moment of inertia is I bs_YY The blue hollow dot represents the center of mass C of the simulated vehicle. vs That is, under the simulated working condition including the effective load, the vertical height of the vehicle's center of gravity is...H vs_CG The simulated car has a mass of M vs The pitch moment of inertia is I vs_YY . Figure 5 Using the unloaded state as the initial reference for the vehicle's center of gravity and attitude, the influence of the effective load on the vehicle's center of gravity and initial pitch angle is presented by comparing the unloaded and loaded conditions. Figure 5 Gray vehicle unloaded front wheelbase L VCF Excluding unsprung mass, the front wheelbase L in the unloaded state of the vehicle body bCF A schematic diagram comparing the changes before and after the operation under empty and fully loaded conditions.

[0056] This embodiment uses a fully loaded state as an example for explanation.

[0057] Based on the unloaded parameters obtained from S2, the vehicle's inertial parameters (such as center of mass position and pitch inertia) and attitude parameters (such as vehicle body sag and initial pitch angle) under full load conditions are calculated through mass transformation. The specific process is explained below.

[0058] S31, Calculation of the Center of Mass in Analysis By passing the front wheel contact point P F Using the front axis of the point as a reference, calculate the analytical center of mass C of the vehicle under full load condition after adding effective load. vs and the vehicle's sprung center of gravity C ss : (1)

[0059] (2) (3)

[0060] (4) Among them, M vs For full load mass, L vs M is the wheelbase before the fully loaded axle mass. vc For unloaded load mass, L vcF M is the front wheelbase with unloaded axle mass. pF For the quality of front-seat passengers, X pF For the mass coordinates of the front-seat passengers, M pR For the quality of rear passengers, X pR M represents the mass coordinates of rear-seat passengers. T For the quality of the suitcase, X T H is the x-axis coordinate of the luggage mass. vs-CGH is the height of the vehicle's center of gravity when fully loaded. vc-CG Z is the height of the vehicle's center of gravity in its unloaded state. hpF For the sake of front-seat passenger quality, X hpR For the sake of rear passenger quality, Z T For the weight and height of the suitcase.

[0061] Based on the above four formulas, the location C of the center of mass can be analytically obtained. vs and the vehicle's sprung center of gravity C ss .

[0062] S32, Key Parameter Transformation Formula S321. Analyze the moment of inertia at the vehicle's center of mass: (5) Among them, I vc_YY This represents the rotational inertia of an unloaded vehicle.

[0063] S322. Changes in posture due to increased payload (passengers + cargo): (6-a) (6-b) Among them, M vsF For full load front axle mass, L vsR L is the wheelbase after the axle is fully loaded. v M is the wheelbase for the fully loaded axle mass. vsR For the fully loaded rear axle mass, L vsF The wheelbase before full load axle mass.

[0064] S323. Calculate the settlement of points A and B of the damping tower using formulas (6-a), (6-b), (7-a), and (7-b), which represents the difference in shaft mass between the unloaded and fully loaded states: (7-a) (7-b) Where, ΔM vF Let ΔM be the change in front axle mass. vR This represents the change in rear axle mass. For unloaded front axle mass, This refers to the unloaded rear axle mass.

[0065] S324, Multiply stiffness of front and rear suspensions: (8-a) (8-b) in, k rFTo ensure adequate stiffness of the front suspension between the shock absorber tower and the tire contact point. k rR To ensure adequate stiffness of the rear suspension between the shock absorber tower and the tire contact point. k wF The front suspension wheel center stiffness is between the shock absorber tower and the wheel center. k wR The rear suspension wheel center stiffness is between the shock absorber tower and the wheel center. k tF For the appropriate stiffness, k tR To ensure adequate stiffness.

[0066] S325. Using formulas (9-a) and (9-b) and L vsF L vsR Relational calculation of analytical quality center C vs The subsidence δ at the location vs : (9-a) (9-b) (10) S326. Initial pitch angle caused by sinking: (11) Subsequently, these calculated parameters are assigned or configured to the dynamic model established by S1 as the initial physical conditions for its dynamic response calculation. This allows the same model to accurately simulate various real-world usage scenarios, from no-load to full-load.

[0067] S4. Determine the forces acting on the dynamic model.

[0068] To accurately simulate impact dynamics, various key forces need to be systematically considered in the model. These forces are determined by corresponding force functions, which are constructed based on real vehicle characteristic data, primarily from the following sources: K&C data refers to the kinematics and compliance test data of the suspension system. This data is obtained through a dedicated test bench and can accurately describe the geometric motion of the suspension and its elastic deformation characteristics under force.

[0069] Test data of components (such as the characteristic curve of vibration damper).

[0070] At least the following forces need to be considered: external inputs (blue arrows) and internal forces expressed as functions (see [link]). Figure 6 As shown. Where Z rF (t) represents the difference between the previous point (P) and the previous point (t) caused by the unevenness of the road surface in the vertical direction.F The vertical displacement of the grounding point; Z rR (t) is the result of the subsequent (point P) R The vertical displacement of the grounding point. V x0 Let A be the longitudinal departure speed of the vehicle during the analysis. x This is the input for changes in longitudinal acceleration during analysis.

[0071] Figure 6 The specific description of the internal forces represented by functions is shown in Table 3. Table 3 is a function table of internal forces.

[0072] Table 3

[0073] Table 2 The unevenness of the road surface in the vertical direction caused the previous (point P) F The upward and downward speeds of the grounding point The unevenness of the road surface in the vertical direction caused the previous (point P) R The upward and downward velocity at the grounding point. F xpF (t), F xpR (t) represents traction or braking force. The sum of traction forces should be the input front-to-rear acceleration and the corresponding force. The driving force distribution between the front and rear wheels should be determined based on whether it is front-wheel drive or rear-wheel drive. Braking force is the input deceleration. The braking force distribution between the front and rear tires is based on the ratio of the vertical load at the contact point of the front and rear tires according to the braking curve.

[0074] S5. Establish the vehicle dynamics equations.

[0075] Based on the model in S1, the model parameters configured in S3, and all force functions defined in S4, a set of governing equations describing the dynamic behavior of the entire vehicle system is established according to Newton-Euler's laws of motion. The model in this embodiment can analyze the impact response under combined operating conditions, such as... Figure 7 The force analysis shown requires consideration not only of the vertical displacement excitation of the wheels caused by road surface potholes (Z) rF (t),Z rR (t) must also be considered in conjunction with the longitudinal force (F) generated at the tire contact point by driving or braking at the tire contact point. xpF (t),F xpR (t)). Figure 7 middle F xA 、F xB 、M A 、M B These symbols are used to illustrate the transmission relationships of suspension forces, tire forces, inertial forces, and torques. F xAThe longitudinal equivalent resultant force of the front unsprung mass is composed of the longitudinal force of the tire and the inertial force of the front unsprung mass, and is used to demonstrate the longitudinal force balance relationship of the front unsprung mass. F xB The longitudinal equivalent resultant force of the rear unsprung mass is composed of the longitudinal force of the tire and the inertial force of the rear unsprung mass, and is used to demonstrate the longitudinal force balance relationship of the rear unsprung mass. M A The resultant moment of the unsprung mass around the suspension mounting point is used to explain the principle of torque generation for resisting pitching impact on the suspension side. M B This is the resultant torque of the unsprung mass around the suspension mounting point, used to explain the principle of torque generation for the suspension side's anti-lift force. Figure 7 middle, These represent the longitudinal inertial forces of the front and rear unsprung masses, respectively. These represent the vertical inertial forces of the unsprung masses at the front and rear, respectively. Ω represents the angular acceleration and inertial torque of the front and rear wheels, respectively, and Ω is the wheel's angular velocity. The vertical displacement of the front suspension mounting point... z A Vertical displacement of the vehicle body z s With pitch angle ψ s A joint decision. for Figure 7 The auxiliary schematic expression in the diagram is used to visually represent the combined pitching moment of the longitudinal forces of the front and rear axles on the sprung center of mass. Figure 7 The geometric expression for the vertical position of the upper pivot point of the front suspension is as follows: Z s0 +Z A =Z s0 +Z s L bsF sin ( ψ s0 +ψ s The geometric relationship expression for the vertical position of the upper pivot point of the rear suspension is as follows: Z s0 +Z B =Z s0 +Z s L bsR sin ( ψ s0 +ψ s ).in, Z s0 The initial vertical height of the sprung center of mass. Z s This represents the vertical displacement of the spring-loaded center of mass. Z A Let be the vertical displacement of the upper pivot point A of the front suspension. Z B Let be the vertical displacement of the upper pivot point B of the front suspension. L bsF The horizontal distance from the sprung center of gravity to the front suspension pivot point. L bsR It is the longitudinal distance from the sprung center of mass to the rear suspension pivot point. ψ s0 The initial pitch angle, ψ s The dynamic pitch angle is given by this formula. This formula shows that the vertical position of the front suspension pivot is determined by the vertical translation of the sprung center of mass and the vehicle pitch motion. It is used to establish the geometric relationship between the vehicle's degrees of freedom and the suspension's working stroke, and is the basis for calculating suspension forces.

[0076] Figure 7 The auxiliary symbols, expressions, and arrows in the diagram are only used to clearly illustrate the transmission relationship between force and torque, and to help understand the mechanical mechanism of the model. They do not participate in solving the dynamic equations.

[0077] Longitudinal forces generate anti-pitch forces through the geometry of the suspension, altering the vertical loads on the front and rear suspensions. These changes in suspension load affect its ability to filter wheel vertical bounce. This model introduces an anti-pitch force function based on K&C data and couples all forces and degrees of freedom into a unified set of dynamic equations for solution, thus accurately reproducing the vehicle's impact dynamics under real and demanding user scenarios such as braking over bumps and accelerating over potholes. This is the key to this invention's high-precision prediction, distinguishing it from simple vibration models.

[0078] Considering the compatibility equations for damping towers A and B, the vehicle's forward and backward motion equations, the equations for the vertical direction of the sprung mass, the equations for the rotational direction of the sprung mass, and the equations for the vertical direction of the unsprung mass, the governing equation matrix of the 5-DOF analytical model is as follows: (12-a) (12-b) in,

[0079]

[0080] Among them, Z S0 To analyze the quality conditions from the road surface to point C bs The initial position of M; V =M bs +M uF +M uR , is the total mass of the vehicle; M bs For the vehicle body mass including passengers and luggage; M uF M is the unsprung mass of the front suspension; uR The mass under the rear suspension spring; F is the longitudinal acceleration; xpF F xpR f is the longitudinal contact force on the outer side of the contact points of the front and rear tires; saF (F xpF ), f saR (F xpR ) represents the load that the front and rear wheels resist when sinking or lifting; f ssF (Z A -Z uF ), f ssR (Z B -Z uR The load is the vertical load between the front and rear wheels acting on the top of the suspension tower and the unsprung mass. The vertical front-to-back vibration reduction load between the vibration reduction tower and the unsprung mass; f is the vertical forward and backward frictional force located between the vibration damping tower and the unsprung mass; tsF (Z uF -Z rF The force is the spring force on the front tire side. f is the front tire side damping force; saF (F xpF ), f taF (F xpF ) represents the pitch load on the front suspension side and the tire side.

[0081] S6. Solve the dynamic equations and obtain the dynamic response using the numerical integration algorithm.

[0082] Since the equations established in S5 are typically nonlinear ordinary differential equations, numerical methods are required to solve them. To solve the vehicle dynamics equations established in step S5 using a numerical integration algorithm, they must first be transformed into state-space equations, as shown in equation (13-a): (13-a) In formula (13-a): (13-b) (13-c) Where I is the identity matrix, K is the stiffness matrix, and X v For the vehicle's forward and backward displacement, Z s Let ψ be the vertical displacement of the mass on the spring. S Z is the rotational displacement of the sprung mass. uF Z represents the vertical displacement of the unsprung mass. uR Q represents the vertical displacement of the unsprung mass. nc is the governing equation matrix.

[0083] In a preferred embodiment, the state-space equations are solved using a fourth-order Runge-Kutta time integration algorithm.

[0084] The coefficients in the algorithm can be: α2=α3=β2=γ3=1 / 2, α4=δ4=1, μ1=μ4=1 / 6; μ2=μ3=1 / 3. The fourth-order Runge-Kutta time integration algorithm is shown in formula (14-a): (14-a) In formula (14-a): (14-b) (14-c) (14-d) (14-e) Among them, {K i} represents the stiffness matrix, and Δt represents the time variation.

[0085] This algorithm boasts high accuracy and stability, making it suitable for vehicle dynamics simulation. Its calculation process is as follows: Figure 7 As shown, the dynamic response of the system in the time domain can be obtained through iterative calculation.

[0086] The dynamic response includes, but is not limited to, the displacement, velocity, and acceleration time history curves of the entire vehicle and key components (such as the body and wheels), as well as the dynamic loads and stresses at each connection point. Based on these dynamic loads, the stress response of each component can be further calculated. This quantitative data can be directly used to objectively evaluate performance indicators such as impact strength and ride comfort.

[0087] This embodiment proposes a 5-DOF lumped mass model. By integrating key mechanical data such as tire force, suspension spring force, suspension damper characteristics, and suspension friction, it overcomes the limitations of analysis under single driving conditions. It can effectively adapt to any vehicle driving scenario, including constant speed, acceleration, and deceleration, and accurately analyzes the nonlinear response region of the suspension under different operating conditions, providing precise mechanical basis for suspension performance optimization. By employing the fourth-order Runge-Kutta time integration algorithm, it can efficiently and accurately obtain complete data on vehicle displacement, velocity, acceleration, and the stress response of each component. This provides comprehensive and accurate quantitative references for vehicle structural strength assessment, component reliability verification, and ride comfort optimization, significantly improving the scientific rigor and engineering application value of vehicle impact performance analysis.

[0088] For complex road surfaces such as potholes and bumps of various shapes that users may encounter in actual use, the analysis scheme proposed in this invention has good adaptability and can comprehensively cover the impact performance analysis needs of diverse driving scenarios, greatly improving the practicality and comprehensiveness of vehicle impact performance analysis, and can more realistically simulate the force state of the vehicle in actual driving.

[0089] This application also provides an electronic device, which includes a memory and a processor. The memory stores a computer program that is executed by the processor. When the computer program is executed by the processor, it causes the device equipped with the processor to perform the vehicle impact performance analysis method as described in any of the above embodiments. Next, refer to Figure 8 Example electronic device 100 is used to describe an analysis method for implementing the vehicle impact performance of embodiments of this application.

[0090] like Figure 8 As shown, the electronic device 100 includes a processor 110, a memory 120, and a communication interface 130. The processor 110, the memory 120, and the communication interface 130 can be interconnected and communicate via a communication bus 140 and / or other forms of connection mechanisms (not shown).

[0091] It should be noted that Figure 8 The components and structure of the electronic device 100 shown are merely exemplary and not limiting; the electronic device may also have other components and structures as needed.

[0092] Optionally, the communication interface 130 may also include a transmitter and / or a receiver.

[0093] The processor 110 may be a microcontroller unit (MCU), a central processing unit (CPU), a digital signal processor (DSP), a microcontroller and embedded device, or other processing units with data processing capabilities and / or instruction execution capabilities.

[0094] The memory 120 can be various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM), cache memory, synchronous dynamic random access memory (SDRAM), etc. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may also be stored on the computer-readable storage medium, and the memory 120 can execute the program instructions to implement the vehicle impact performance analysis method described in the embodiments of this application above.

[0095] This application also provides a storage medium storing a computer program that runs on a computer. When the computer program runs, it causes the computer to execute the vehicle impact performance analysis method as described in any of the above embodiments.

[0096] In this application, the electronic device and storage medium provided in the embodiments are used to execute the corresponding methods provided above. Therefore, the beneficial effects they can achieve can be referred to the beneficial effects in the corresponding methods provided above, and will not be repeated here.

[0097] Finally, it should be noted that the above technical solution is only one implementation method of this application. For those skilled in the art, based on the application methods and principles disclosed in this application, it is easy to make various types of improvements or modifications, and not limited to the methods described in the specific implementation methods above. Therefore, the methods described above are only preferred and have no limiting significance.

Claims

1. A method for analyzing the impact performance of a vehicle, characterized in that, The analytical method includes: Establish a dynamic model of the whole vehicle, which at least characterizes the longitudinal motion of the vehicle, the vertical and pitch motion of the sprung mass, and the vertical motion of the front and rear wheels. Acquire the basic state parameters and road excitation data of the vehicle under no-load conditions; Based on the aforementioned basic state parameters, the dynamic model is configured such that the inertial parameters and attitude of the dynamic model correspond to the target load state. Based on the vehicle driving conditions and the road excitation data, the forces acting on the dynamic model are determined. The forces include at least the suspension spring force, damping force, friction force, and anti-pitch force. Based on the aforementioned dynamic model and the aforementioned forces, a set of vehicle dynamic equations is established; The dynamic equations are solved using numerical calculation methods to obtain the dynamic response characterizing the impact performance of the vehicle.

2. The method for analyzing the impact performance of a vehicle according to claim 1, characterized in that, The dynamic model is a lumped mass model.

3. The method for analyzing the impact performance of a vehicle according to claim 2, characterized in that, The lumped mass model is a five-degree-of-freedom model, which includes: the overall longitudinal displacement of the vehicle, the vertical displacement of the sprung mass, the pitch angle displacement of the sprung mass, the vertical displacement of the unsprung mass of the front wheel, and the vertical displacement of the unsprung mass of the rear wheel.

4. The method for analyzing the impact performance of a vehicle according to claim 1, characterized in that, Based on the aforementioned fundamental state parameters, the dynamic model is configured, including: Based on the basic state parameters, the vehicle inertial parameters and attitude parameters after adding the effective load are calculated, and the vehicle inertial parameters and attitude parameters are set as the initial physical conditions for the dynamic model to perform dynamic response calculation.

5. The method for analyzing the impact performance of a vehicle according to claim 1, characterized in that, The road surface excitation data is two-dimensional planar coordinate data, including the vehicle's longitudinal position and its corresponding vertical height on the road surface. The sampling density in areas where the road surface curvature change is greater than a preset threshold is greater than the sampling density in areas where the road surface curvature change is less than or equal to the preset threshold.

6. The method for analyzing the impact performance of a vehicle according to claim 1, characterized in that, The forces in each direction are determined by corresponding force functions, which are constructed based on at least one of the K&C data of the vehicle suspension and tires and component test data.

7. The method for analyzing the impact performance of a vehicle according to claim 6, characterized in that, The anti-pitch force includes anti-nose force and anti-lift force generated by the suspension geometry.

8. The method for analyzing the impact performance of a vehicle according to claim 1, characterized in that, The dynamic response includes at least one of the following: displacement, velocity, acceleration, and stress of the whole vehicle and key components.

9. An electronic device, characterized in that, The electronic device includes a memory and a processor, the memory storing a computer program executed by the processor, the computer program, when executed by the processor, causing the device equipped with the processor to perform the method for analyzing the impact performance of a whole vehicle as described in any one of claims 1-8.

10. A storage medium, characterized in that, The storage medium stores a computer program that runs on a computer and, when running, causes the computer to perform the method for analyzing the impact performance of a vehicle as described in any one of claims 1-8.

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