Method and system for optimizing force transmission path of lightweight engine hood and electronic equipment

Abstract

The invention relates to the technical field of vehicle engineering, and discloses a force transmission path optimization method and system of a lightweight engine hood and electronic equipment. According to the method, a lightweight engine hood model is constructed, and a working condition model representing linear statics of the engine hood model under different working conditions is established; establishing a collision simulation model reflecting nonlinear collision of the engine hood model, forming a design area model according to the working condition model and the collision simulation model, determining a displacement matrix of the collision simulation model, enabling the collision simulation model to be equivalent to a new working condition model representing a static load based on the displacement matrix, and carrying out topological optimization on the new working condition model, obtaining a new design area model, and generating an optimal force transmission path in the engine hood model according to the new design area model; by means of the method, precise simulation and optimization design of the force transmission path of the design area of the engine hood are achieved, and through the optimal force transmission path, the material utilization rate is increased, the vehicle mass is reduced, and the cost is reduced.

Description

Technical Field

[0001] The present application relates to the field of vehicle engineering technology, and in particular to a method, system and electronic equipment for optimizing the force transmission path of a lightweight engine hood. Background Art

[0002] The global trend toward lightweighting vehicles continues to accelerate, driven by the "carbon peak" target. As a key subsystem for vehicle mass distribution, the hood system's reinforcement plate structure faces severe design challenges, driven by the dual constraints of pedestrian protection regulations and lightweighting targets.

[0003] Traditional hood reinforcement panel design uses an empirically based method of arranging uniform cross-section beams, which often leads to the following problems: 1. Inadequate material utilization: Analysis reveals that a significant amount of material in traditional solutions is not effectively involved in force transmission, resulting in significant redundant mass; 2. Uncontrolled dynamic response: In HIC (Head Injury Criterion) testing, the efficiency of traditional reinforcement panels in transmitting collision energy is significantly lower than the theoretical optimal value, and there is a risk of local buckling caused by stress wave reflection; 3. Multi-objective imbalance: Related design methods are unable to quickly balance multiple objectives. Clearly, a new method for optimizing the force transmission path of lightweight hoods is urgently needed to address at least one of these issues.

[0004] It should be noted that the above content only provides background technical information related to this application and does not necessarily constitute prior art. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the present application provides a method, system and electronic equipment for optimizing the force transmission path of a lightweight engine hood, so as to achieve accurate simulation and optimized design of the force transmission path in the design area of the engine hood.

[0006] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by practice of the present application.

[0007] According to one aspect of an embodiment of the present application, a method for optimizing the force transmission path of a lightweight engine hood is provided, comprising: constructing a lightweight engine hood model; establishing a linear static working condition model that characterizes the engine hood model under different working conditions, and establishing a collision simulation model that reflects the nonlinear collision of the engine hood model, so as to form a design area model based on the working condition model and the collision simulation model; determining the displacement matrix of the collision simulation model, and based on the displacement matrix, equating the collision simulation model to a new working condition model that characterizes the static load; performing topological optimization on the new working condition model to obtain a new design area model, and generating an optimal force transmission path in the engine hood model based on the new design area model.

[0008] In one embodiment of the present application, based on the aforementioned scheme, a lightweight engine hood model is constructed, including: obtaining a finite element mesh model including the engine hood, the front cabin structure and the firewall, and obtaining material property parameters of the engine hood, the material property parameters including elastic modulus, Poisson's ratio and density; determining the constraint boundary conditions of the finite element mesh model based on the hinge mounting point, the lock mounting point and the contact area with the front cabin structure of the engine hood; filling the preset reinforcement plate area in the finite element mesh model according to the material property parameters of the engine hood to construct the engine hood model.

[0009] In one embodiment of the present application, based on the aforementioned scheme, a linear static working condition model is established to characterize the engine hood model under different working conditions, including: establishing a collision equivalent working condition model by applying an equivalent static load at a first preset evaluation point of the engine hood; establishing a bending stiffness working condition model by fixing the hinge mounting point of the engine hood and applying a first moment to the lock mounting point of the engine hood; establishing a torsional stiffness working condition model by fixing the hinge mounting point on the first side of the engine hood and applying a second moment to the second side of the engine hood, wherein the first side of the engine hood is the opposite side of the second side of the engine hood; establishing an anti-dent working condition model by applying a normal force at a second preset evaluation point in a preset reinforcement plate area; and establishing a bending modal model and a torsional modal model by performing modal analysis on the engine hood.

[0010] In one embodiment of the present application, based on the above-mentioned scheme, the displacement matrix of the collision simulation model is determined, and based on the displacement matrix, the collision simulation model is equivalent to a new working condition model that characterizes the static load, including: performing dynamic nonlinear analysis on the collision simulation model to obtain the displacement matrix; calculating the linear stiffness matrix based on the unit density of each unit in the design area; calculating the equivalent static load based on the displacement matrix and the linear stiffness matrix; and applying the equivalent static load to the collision equivalent working condition model to equate the collision simulation model to a new collision equivalent working condition model.

[0011] In one embodiment of the present application, based on the aforementioned scheme, the collision simulation model is equivalent to a new working condition model that characterizes the static load based on the displacement matrix, and further includes: extracting the displacement matrix once at a preset interval, and calculating the corresponding equivalent static load based on the extracted displacement matrix, so as to equate the collision simulation model to a new working condition model that characterizes the static load through the moving time window technology and the equivalent static load method.

[0012] In one embodiment of the present application, based on the above-mentioned scheme, the new working condition model is topologically optimized, including: determining the unit density of each unit in the design area as the design variable, determining the weighted flexibility of the first preset evaluation point in the new collision equivalent working condition model as the optimization target, and determining the constraint conditions based on the bending stiffness obtained from the bending stiffness working condition model, the torsional stiffness obtained from the torsional stiffness working condition model, the displacement of the second preset evaluation point in the anti-dent working condition model, the bending mode obtained from the bending mode working condition model, the bending mode obtained from the torsional mode working condition model, and the number of units with the current density being the preset density and the total number of units; using a solid isotropic material penalty model for iterative solution, using the adjoint variable method for sensitivity analysis, determining the density filtering radius, and determining the convergence criterion to complete the topology optimization.

[0013] In one embodiment of the present application, based on the aforementioned scheme, topology optimization is performed on the new working condition model to obtain a new design area model, which also includes: topology optimization is performed on the new working condition model to obtain a topology optimization result, updating the design variables according to the topology optimization result, and updating the design area model according to the updated design variables until the topology optimization result meets the convergence criterion or reaches a preset step threshold, stopping updating the design area model to obtain the new design area model.

[0014] In one embodiment of the present application, based on the aforementioned scheme, an optimal force transmission path is generated in the engine hood model according to the new design area model, including: determining the unit density of each unit in the design area according to the design area model, and generating a density cloud map based on the unit density of each unit in the design area to generate the optimal force transmission path in the engine hood model.

[0015] According to one aspect of an embodiment of the present application, a force transmission path optimization system for a lightweight engine hood is provided, including: a first construction module for constructing a lightweight engine hood model; a second construction module for establishing a working condition model that characterizes the linear statics of the engine hood model under different working conditions, and establishing a collision simulation model that reflects the nonlinear collision of the engine hood model, so as to form a design area model based on the working condition model and the collision simulation model; an equivalent module for determining the displacement matrix of the collision simulation model, and equating the collision simulation model to a new working condition model that characterizes the static load based on the displacement matrix; an optimization module for performing topological optimization on the new working condition model to obtain a new design area model, and generating an optimal force transmission path in the engine hood model according to the new design area model.

[0016] According to one aspect of an embodiment of the present application, an electronic device is provided, comprising: one or more processors; a storage device for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the electronic device implements the force transmission path optimization method for a lightweight engine hood as described in any one of the above embodiments.

[0017] The beneficial effects of the present application are as follows: The present application constructs a lightweight hood model, establishes a working condition model that characterizes the linear statics of the hood model under different working conditions, and establishes a collision simulation model that reflects the nonlinear collision of the hood model, so as to form a design area model according to the working condition model and the collision simulation model, determine the displacement matrix of the collision simulation model, and based on the displacement matrix, the collision simulation model is equivalent to a new working condition model that characterizes the static load. The new working condition model is topologically optimized to obtain a new design area model, and an optimal force transmission path is generated in the hood model according to the new design area model. The above method realizes accurate simulation and optimal design of the force transmission path of the design area of the hood, and through the optimal force transmission path, while ensuring the strength and safety performance of the vehicle, the material utilization rate is improved, the vehicle weight is reduced, and the cost is reduced.

[0018] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are incorporated into and constitute a part of the specification, illustrating embodiments consistent with the present application and, together with the specification, serving to explain the principles of the present application. It is obvious that the drawings described below are merely some embodiments of the present application, and a person of ordinary skill in the art can derive other drawings based on these drawings without inventive effort. In the drawings:

[0020] Figure 1 is a flow chart of a method for optimizing a force transmission path of a lightweight engine hood according to an exemplary embodiment of the present application;

[0021] Figure 2 is a flow chart of a method for optimizing a force transmission path of a lightweight engine hood according to another exemplary embodiment of the present application;

[0022] Figure 3 1 is a schematic diagram of a design area after solid filling, illustrating a method for optimizing a force transmission path of a lightweight engine hood according to an exemplary embodiment of the present application;

[0023] Figure 4 is a schematic diagram of a force transmission path analysis result of a force transmission path optimization method for a lightweight engine hood according to an exemplary embodiment of the present application;

[0024] Figure 5 is a block diagram of a force transmission path optimization system for a lightweight engine hood shown in an exemplary embodiment of the present application;

[0025] Figure 6 A schematic diagram of the structure of a computer system suitable for implementing an electronic device according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0026] The following will describe the embodiments of the present application with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand the other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be understood that the preferred embodiments are only for the purpose of illustrating the present application and are not intended to limit the scope of protection of the present application.

[0027] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. Therefore, the illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0028] In the following description, a large number of details are discussed to provide a more thorough explanation of the embodiments of the present application. However, it is obvious to those skilled in the art that the embodiments of the present application can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present application difficult to understand.

[0029] First of all, it should be noted that normal force refers to the force perpendicular to the contact surface of the object.

[0030] The penalty function method, also known as the multiplier method, transforms a constrained optimization problem into an unconstrained optimization problem: where M is a sufficiently large positive number that acts as a penalty, called the penalty factor, and F(x,M) is called the penalty function. The internal penalty function method, also known as the barrier penalty method, searches within the feasible region, with the constraint boundary acting like a fence. When the current solution is far from the constraint boundary, the penalty function value is very small; otherwise, the penalty function value approaches infinity. In evolutionary computation, researchers prefer the external penalty function method primarily because it does not require an initial feasible solution.

[0031] The Solid Isotropic Material with Penalization Model (SIMP) method is a widely used optimization design strategy, especially in the field of structural topology optimization. The core idea of the SIMP method is to discretize the design space into a finite number of elements (usually finite elements) and describe each element using a set of density variables. These density variables represent the material presence of each element, and their values are usually between 0 and 1. Specifically: when the density variable is 0, it means that the element has no material, that is, it is in a state of no material filling. When the density variable is 1, it means that the element is filled with material with the maximum density allowed in the design space, that is, it is in a state of full material filling. The SIMP method approaches the ideal material distribution in a continuous manner by introducing a penalty factor. During the optimization process, as the penalty factor increases, the intermediate density values will be gradually eliminated, and the final result is a "0-1" distribution, that is, the material is either completely present or completely absent, which is consistent with the actual physical situation.

[0032] Topology optimization takes material distribution as the optimization object. Through topology optimization, the best distribution scheme can be found in the design space of uniformly distributed materials.

[0033] Figure 1 The present invention is a flowchart of a method for optimizing the force transmission path of a lightweight engine hood according to an exemplary embodiment of the present invention. The method for optimizing the force transmission path of a lightweight engine hood can be executed by a computing and processing device. The computing and processing device can be Figure 1 The computer device 102 shown in FIG. Figure 1 As shown, the method for optimizing the force transmission path of a lightweight engine hood includes at least steps S110 to S140, which are described in detail as follows:

[0034] In step S110 , a lightweight engine hood model is constructed.

[0035] In one embodiment of the present application, the process of constructing a lightweight engine hood model includes the following steps: obtaining a finite element mesh model including the engine hood, the front cabin structure and the firewall, and obtaining the material property parameters of the engine hood, the material property parameters including the elastic modulus, Poisson's ratio and density; determining the constraint boundary conditions of the finite element mesh model based on the hinge mounting point, the lock mounting point and the contact area with the front cabin structure of the engine hood; filling the preset reinforcement plate area in the finite element mesh model according to the material property parameters of the engine hood to construct a lightweight engine hood model.

[0036] In this embodiment, it should be noted that the hood in the following content refers to the engine hood. First, the initial data is input. The input includes a finite element mesh model of the complete hood assembly, the front cabin structure and the firewall (wherein the unit size of the finite element mesh model can be defined as ≤5mm, and the mesh consists of at least one unit), and the material property parameters of the engine hood must include elastic modulus, Poisson's ratio and density. Secondly, the design space is defined. The design space definition includes boundary condition definition and filling processing. Among them, the boundary condition definition is achieved by retaining the hinge mounting point of the inner panel of the hood, the lock mounting point and the contact area with the front cabin structure as fixed constraint boundaries, i.e., constraint boundary conditions; the filling processing can be achieved by using hexahedral solid units to fill the original reinforcement plate area, i.e., the preset reinforcement plate area with full density (i.e., unit density ρ = 1), and the filled material property parameters are consistent with the material property parameters of the hood.

[0037] In step S120, a working condition model representing the linear statics of the engine hood model under different working conditions is established, and a collision simulation model reflecting the nonlinear collision of the engine hood model is established, so as to form a design region model according to the working condition model and the collision simulation model.

[0038] In one embodiment of the present application, the process of establishing a linear static working condition model that characterizes the engine hood model under different working conditions includes the following steps: establishing a collision equivalent working condition model by applying an equivalent static load at a first preset evaluation point of the engine hood; establishing a bending stiffness working condition model by fixing the hinge mounting point of the engine hood and applying a first moment to the lock mounting point of the engine hood; establishing a torsional stiffness working condition model by fixing the hinge mounting point on the first side of the engine hood and applying a second moment to the second side of the engine hood, where the first side of the engine hood is the opposite side of the second side of the engine hood; establishing an anti-dent working condition model by applying a normal force at a second preset evaluation point in a preset reinforcement plate area; establishing a bending modal model and a torsional modal model by performing modal analysis on the engine hood.

[0039] In this embodiment, a multi-condition linear model is constructed to characterize the engine hood model. The linear model includes, but is not limited to, a collision equivalent condition model, a bending stiffness condition model, a torsional stiffness condition model, an anti-dent condition model, a bending modal model, and a torsional modal model. Based on the engine hood model, a linear statics model including the following working conditions is established: a linear simulation model, in which the working conditions are provided with an equivalent linear working condition of a head-on collision, namely a collision equivalent working condition (whose load input is a static linear equivalent load), an anti-dent condition, a bending stiffness condition, a torsional stiffness condition, a bending modal condition, and a torsional modal condition. Among them, the loading methods and evaluation indicators corresponding to each working condition type refer to Table 1:

[0040] Table 1

[0041] Working condition type Loading method Evaluation Metrics Collision equivalent conditions Static linear equivalent load / Bending stiffness condition The hinge point is fixed and the locking point applies Z-direction torque Bending stiffness ≤ first preset target value Torsional stiffness condition The hinge point on one side is fixed, and the X-direction moment is applied to the opposite side Torsional stiffness ≤ second preset target value Anti-dent working conditions Apply normal force at key points in the stiffener area Displacement ≤ the third preset target value Bending mode conditions Calculate the first n modes in the free state Bending mode ≤ the fourth preset target value Torsional mode conditions Calculate the first n modes in the free state Torsional mode ≤ fifth preset target value

[0042] As can be seen from Table 1, the working condition types include collision equivalent working condition, anti-dent working condition, bending stiffness working condition, torsional stiffness working condition, bending modal working condition and torsional modal working condition. The corresponding loading methods and evaluation indicators are referred to the above Table 1 and will not be repeated here. It should be noted that this embodiment is only an example. The working condition type and the corresponding loading method and evaluation index can be increased, reduced or changed according to actual needs, and their values can also be modified according to actual needs. This application does not limit this. Through the multi-condition coordination mechanism, the collision equivalent condition is used as the active optimization target, and the performance of the other conditions is guaranteed by constraints, and the multi-constraint coupling is handled by the Lagrange multiplier method.

[0043] In one embodiment of the present application, a nonlinear collision model, namely a collision simulation model, is constructed. A head impact simulation model is established based on a hood model in accordance with regulatory standards. The operating conditions include collision velocity, collision angle, and head mass for adults and children. The contact algorithm is a penalty function method (wherein the friction coefficient can be set to 0.3).

[0044] In step S130 , a displacement matrix of the collision simulation model is determined, and based on the displacement matrix, the collision simulation model is equivalent to a new working condition model representing a static load.

[0045] In one embodiment of the present application, the displacement matrix of the collision simulation model is determined, and the process of equating the collision simulation model to a new working condition model that characterizes the static load based on the displacement matrix includes the following steps: performing dynamic nonlinear analysis on the collision simulation model to obtain a displacement matrix; calculating a linear stiffness matrix based on the unit density of each unit in the design area; calculating an equivalent static load based on the displacement matrix and the linear stiffness matrix; and applying the equivalent static load to the collision equivalent working condition model to equate the collision simulation model to a new collision equivalent working condition model.

[0046] In this embodiment, since the nonlinear collision simulation model cannot directly use the topology optimization method to find its force transmission path, it needs to be equivalent to a linear working condition model, namely the collision equivalent working condition model. It should be noted that in the topology optimization process based on the variable density method (SIMP), the linear stiffness matrix K of the linear working condition model is L (ρ) is related to the relative density of each unit. The specific calculation method is shown in formula (1):

[0047]

[0048] Among them, K L (ρ) is the linear stiffness matrix, i is the element number, n is the total number of elements, ρ i is the cell density of the i-th cell, p is the penalty factor in the variable density method topology optimization, is the density contribution after penalty, K i is the base stiffness matrix of the i-th unit (corresponding to the stiffness of the solid material). Applying the static linear equivalent load at each moment, i.e., the equivalent static load, to the linear model can generate a collision equivalent working condition model equivalent to the nonlinear analysis.

[0049] The collision simulation model is equivalent to the collision equivalent working condition model through the equivalent static load method. Specifically, at any time t of the collision, the static linear equivalent load F eq The calculation method of (t) refers to formula (2):

[0050] F eq (t) = K L (ρ)·u(t) Formula (2)

[0051] Among them, F eq (t) is the static linear equivalent load corresponding to time t, K L (ρ) is the linear stiffness matrix of the linear working condition model, and u(t) is the displacement matrix of the crash simulation model at time t. The displacement matrix extracted from the crash simulation results is multiplied by the linear stiffness matrix to obtain the equivalent static load. The equivalent static load is the load for the equivalent linear working condition of a head-on collision. The displacement matrix can also be understood as a displacement vector.

[0052] In some embodiments, the material interpolation strategy is to use the SIMP-RAMP hybrid interpolation method, and use the RAMP function to avoid numerical singularity when the density is less than a preset density threshold (e.g., ρ<0.3). The SIMP-RAMP hybrid interpolation method optimizes the material distribution by combining two strategies: using RAMP interpolation to avoid numerical singularity in low-density areas (e.g., ρ<0.3), and using SIMP interpolation to penalize intermediate densities in high-density areas. Specifically, by setting the preset density threshold ρ th , switch the interpolation formula according to the density value. It can not only avoid the vanishing gradient in the low-density area and improve the optimization stability, but also balance the penalty effect and numerical robustness to improve the convergence efficiency. Among them, RAMP (Rational Approximation of Material Properties) is a method of smoothly interpolating material properties through rational functions, which is mainly used to avoid numerical singularity problems in low-density areas. The topological density field is mapped to the collision model density parameters (nonlinear interpolation function) in real time through the material interpolation module to achieve synchronous update.

[0053] In one embodiment of the present application, the displacement matrix is extracted once at a preset interval, and the corresponding equivalent static load is calculated based on the extracted displacement matrix, so that the collision simulation model is equivalent to a new working condition model that characterizes the static load through the moving time window technology and the equivalent static load method.

[0054] In this embodiment, the equivalent static load is calculated using a moving time window technique. The displacement field, i.e., the displacement matrix u(t), is extracted at regular time intervals, and the equivalent static load is calculated using the above formula (2).

[0055] In step S140 , topology optimization is performed on the new working condition model to obtain a new design region model, and an optimal force transmission path is generated in the engine hood model according to the new design region model.

[0056] In one embodiment of the present application, the process of topological optimization of a new working condition model includes the following steps: determining the unit density of each unit in the design area as a design variable, determining the weighted flexibility of the first preset evaluation point in the new collision equivalent working condition model as the optimization target, and determining the constraint conditions based on the bending stiffness obtained from the bending stiffness working condition model, the torsional stiffness obtained from the torsional stiffness working condition model, the displacement of the second preset evaluation point in the anti-dent working condition model, the bending mode obtained from the bending mode working condition model, the bending mode obtained from the torsional mode working condition model, and the number of units with a current density of the preset density and the total number of units; using a solid isotropic material penalty model for iterative solution, using the adjoint variable method for sensitivity analysis, determining the density filtering radius, and determining the convergence criterion to complete the topology optimization.

[0057] In this embodiment, the optimization target adopts multi-objective optimization, that is, multi-objective topology optimization. The design variable is the unit density of each unit in the design area, and the optimization target is the weighted flexibility sum of the static linear equivalent load condition, that is, the new collision equivalent condition model. The constraint conditions are that the bending stiffness is greater than the first preset target value, the torsional stiffness is greater than the second preset target value, the displacement of each preset evaluation point of the anti-dent condition is less than the third preset target value, the bending mode is greater than the fourth preset target value, the torsional mode is greater than the fifth preset target value, and the number ratio calculated based on the number of units with the current density being the preset density and the total number of units is less than the preset threshold (for example, 0.3). The mathematical model refers to formula (3):

[0058]

[0059] In formula (3), ρ i Represents the relative density of the i-th unit, where 0<ρ i <=1; C(ρ) represents the weighted flexibility sum, s represents the sequence number of the first preset evaluation point, m is the total number of the first preset evaluation points, ω s represents the flexibility weight of the sth first preset evaluation point, represents the flexibility of the sth first preset evaluation point, U s represents the displacement of the sth first preset evaluation point, F eq(s) represents the equivalent effect of the sth first preset evaluation point; K tor represents torsional stiffness, K tor_obj Indicates the torsional stiffness target value, i.e., the first preset target value, K bend represents the bending stiffness, K bend_obj represents the bending stiffness target value, i.e., the second preset target value; Z i represents the normal displacement of the i-th head impact point, i.e., the second preset evaluation point, Z i_obj M represents the normal displacement target value of the i-th head impact point, i.e., the third preset target value; tor represents the torsional mode, M tor_obj represents the torsional modal target value, i.e., the fourth preset target value, M bend represents the bending mode, M bend_obj represents the bending modal target value, i.e., the fifth preset target value; V represents the number of units with the current preset density; and V0 represents the total number of units. The first preset evaluation point and the second preset evaluation point may be the same or different, and this application does not limit this.

[0060] In some embodiments, the SIMP algorithm is used for iterative solution; the sensitivity analysis adopts the adjoint variable method; the density filtering radius is determined to be a preset number of times the cell size (for example, the density filtering radius is determined to be 3 times the cell size, that is, r = 3 times the cell size); the convergence criterion can be determined as the change in the objective function for a consecutive preset number of iterations is less than a preset change rate (for example, the objective function change rate is <1% for 5 iterations).

[0061] In some embodiments, constraints are handled through an anti-interference optimization strategy. Specifically, a node displacement amplification factor method is used to enhance local sensitivity for the local response of the anti-concave working condition. This application also includes solving the problem of multi-condition competition and conflict, specifically using a joint objective function weighting strategy to address the performance imbalance caused by traditional sub-objective optimization.

[0062] In one embodiment of the present application, the process of performing topology optimization on the new working condition model to obtain a new design area model also includes the following steps: performing topology optimization on the new working condition model to obtain a topology optimization result, updating the design variables according to the topology optimization result, and updating the design area model according to the updated design variables until the topology optimization result meets the convergence criterion or reaches a preset step threshold, stopping updating the design area model to obtain a new design area model.

[0063] In this embodiment, the convergence criterion can be that the change in the objective function for a preset number of consecutive iterations is less than a preset rate of change (for example, the rate of change of the objective function is <1% for 5 iterations). The preset step threshold can also be a preset number of iterations, which can be set according to actual needs, and this application is not limited to this. It is understandable that the above-mentioned preset number of times and preset rate of change are only for illustration, and this application does not limit this, nor should it bring any limitation to the functions and scope of use of the embodiments of this application.

[0064] In one embodiment of the present application, the process of generating an optimal force transmission path in an engine hood model based on a new design area model includes the following steps: determining the cell density of each unit in the design area based on the design area model, and generating a density cloud map based on the cell density of each unit in the design area to generate an optimal force transmission path in the engine hood model.

[0065] In this embodiment, the unit density of each unit in the design area is determined according to the design area model, the density distribution in the design area is determined based on the unit density of each unit in the design area, a density cloud map is generated based on the density distribution, and the optimal force transmission path is generated according to the density cloud map.

[0066] In one embodiment of the present application, the present application also includes a collaborative update mechanism, including the following modules: a model synchronization module, which is used to map the density distribution, that is, the unit density of each unit in the design area, to the linear model and the collision simulation model at the same time after each iteration; a load update module, which is used to re-extract the equivalent static load based on the collision simulation model obtained according to the updated design variables; and a termination judgment module, which is used to determine convergence and stop collaborative updating when the equivalent load fluctuation rate is less than a preset fluctuation rate (for example, 2%).

[0067] In one embodiment of the present application, topology optimization can also be replaced by parametric morphology optimization: first, feature-driven design is performed, and a library of rib orientations is preset (including but not limited to radial, grid, fractal structures, etc.), and the rib height ratio (for example, the rib height ratio H to thickness t is set to H / t=35) and the inclination angle (for example, θ=45°-60°) are controlled by parameterization. The NURBS curve is used to describe the geometric characteristics of the force transmission path. Secondly, a hybrid optimization strategy is set. In the first stage, the rib type combination is screened based on the genetic algorithm; in the second stage, the sequential quadratic programming (SQP) is used to optimize the rib cross-sectional parameters. Finally, an equivalent criterion is established. An equivalent replacement relationship between the rib structure and the material distribution is established (such as a topological structure with a single H-shaped rib ≈ 15% volume density). It not only conforms to the requirements of traditional manufacturing processes, but also reduces the difficulty of processing.

[0068] In this embodiment, parametric topology optimization is used instead of topology optimization. Specifically, during the feature-driven design phase, a library of rib orientations is first pre-defined. Typical rib patterns are defined, including but not limited to radial (ribs radiating outward from a center), grid (a network of evenly distributed vertical and horizontal ribs), and fractal (multi-level nested ribs designed based on self-similarity). Parametric templates (e.g., rib spacing, intersection type, etc.) are then defined for each pattern.

[0069] Then, the geometric characteristics of the ribs are parametrically controlled, including but not limited to height ratio control by setting the ratio of rib height H to thickness t to H / t=35 to ensure a balance between structural rigidity and lightweight; and inclination angle optimization by parametrically adjusting the inclination angle distribution by setting the angle θ∈[45°, 60°] between the ribs and the force transmission direction.

[0070] Finally, the load transfer path is described using NURBS curves. Specifically, NURBS (Non-Uniform Rational B-Splines) curves are used to fit the load transfer path, generating smooth geometric features. By adjusting the control point weights, the path curvature is optimized to adapt to different load conditions.

[0071] The hybrid optimization strategy phase includes the first stage, which uses a genetic algorithm to select reinforcement type combinations. Using reinforcement pattern, inclination angle, and NURBS control point coordinates as genes, a chromosome code is constructed to complete the code design. A multi-objective fitness function is constructed by integrating metrics such as stiffness, volume, and dent resistance. Selection, crossover, and mutation operations are used to select the Pareto-optimal reinforcement type combination, completing iterative optimization.

[0072] The second stage of cross-sectional parameter optimization using sequential quadratic programming (SQP) is also included. Parameter definition is performed using rib cross-sectional dimensions (e.g., width and thickness) and NURBS curve parameters as optimization variables. Process constraints such as volume fraction and minimum thickness are set to complete the constraint setting. Minimizing structural flexibility (maximizing stiffness) or the displacement response under specified operating conditions is defined as the objective function. The SQP algorithm is used to further optimize cross-sectional parameters based on the rib profile selected by the genetic algorithm.

[0073] During the equivalence criterion implementation phase, finite element analysis or experimental testing is used to establish an equivalent relationship between the reinforcement structure and uniform material distribution. For example, a topological structure with an equivalent volume density of 15% for a single H-shaped reinforcement (calibration for specific working conditions is required). Regression analysis or machine learning is used to fit a mapping function between reinforcement parameters (such as height and inclination) and equivalent material distribution.

[0074] Process suitability verification is performed through the following methods: Manufacturing constraint checks, specifically ensuring that the equivalent structure meets traditional processing requirements such as minimum wall thickness and draft angle. Processing difficulty assessment, specifically simplifying the design through equivalent criteria to avoid increased processing costs due to complex topologies.

[0075] Based on the feedback of the equivalent criterion, the rib parameters or equivalent material distribution are adjusted, and iterative optimization is performed to meet the dual requirements of performance and process.

[0076] Feature-driven design reduces manual trial and error, and hybrid optimization strategies balance global exploration and local refinement, thereby improving design efficiency. The equivalent criterion converts topology optimization results into traditional rib-type structures, reducing processing difficulty and cost. Through multi-stage optimization, a high coverage rate of Pareto optimal solutions for dent resistance, modality, and stiffness is achieved, ensuring performance.

[0077] Figure 2 This is a flow chart of a method for optimizing the force transmission path of a lightweight engine hood according to another exemplary embodiment of the present invention. Figure 2 As shown, the design data envelope is first collected, including but not limited to the finite element mesh model of the complete engine hood, front cabin structure and firewall, including the material properties of elastic modulus, Poisson's ratio and density. Based on the design data envelope, the solid filled hood design area, namely the engine hood model, is obtained. Figure 3 , Figure 3 It is a schematic diagram of the design area after solid filling of the force transmission path optimization method of the lightweight engine hood shown in an exemplary embodiment of the present application. Based on the solid filled hood design area, a collision model of the pedestrian protection head collision test (hereinafter referred to as pedestrian protection head collision) is established, that is, a collision simulation model, and based on the solid filled hood design area, a linear model is established. The linear model includes the following multiple working conditions: pedestrian protection head collision equivalent working conditions, that is, collision equivalent working conditions, anti-dent working conditions, bending and torsional stiffness working conditions, bending and torsional modal working conditions, wherein the bending and torsional stiffness working conditions include bending stiffness working conditions and torsional stiffness working conditions, and the bending and torsional modal working conditions include bending modal working conditions and torsional modal working conditions; a design area model is generated based on the collision model and the linear model, wherein the design area material density of the collision model and the linear model is kept consistent. Based on the collision model, the displacement matrix is calculated, and the static linear equivalent load, that is, the equivalent static load, is calculated according to the displacement matrix. According to the static linear equivalent load, the collision model is equivalent to the head-on collision equivalent working condition, and the topology optimization result is obtained through topology optimization. If the topology optimization result reaches convergence or reaches the preset maximum number of steps, a density cloud map is generated, and then the optimal force transmission path is obtained. Figure 4 , Figure 4This is a schematic diagram of the force transmission path analysis results of a lightweight engine hood force transmission path optimization method, illustrating an exemplary embodiment of this application. If the topology optimization result does not converge or does not reach the preset maximum number of steps, the design region model is updated until the topology optimization result converges or reaches the preset maximum number of steps. The specific method has been described in detail in the previous embodiment and will not be repeated here.

[0078] This application adopts a density mapping method to ensure that the geometric topology between the linear model and the nonlinear model, i.e., the collision simulation model, is updated synchronously, and the final optimization result meets the performance requirements of the nonlinear model of the dynamic system to improve accuracy and reliability. This application improves the coverage of the Pareto optimal solution of dent resistance, modality, and stiffness through the combined objective function of weighted flexibility and quantity ratio, breaking through the local optimal trap of traditional single-objective optimization. This application also finds the optimal force transmission path under the premise of meeting the stiffness and head-impact HIC value goals, improves material utilization, and improves lightweight benefits. Among them, when there are multiple conflicting optimization goals (such as dent resistance, modality, stiffness), the Pareto optimal solution refers to the solution that can no longer improve any one goal without sacrificing the performance of other goals.

[0079] Figure 5 This is a block diagram of a force transmission path optimization system for a lightweight engine hood shown in an exemplary embodiment of the present application. Figure 1 The device can also be applied to other exemplary implementation environments and be specifically configured in other devices. This embodiment does not limit the implementation environment to which the device is applied.

[0080] like Figure 5 As shown, the exemplary force transmission path optimization system for a lightweight engine hood includes: a first building module 510 , a second building module 520 , an equivalent module 530 and an optimization module 540 .

[0081] Among them, the first construction module 510 is used to construct a lightweight engine hood model; the second construction module 520 is used to establish a working condition model that characterizes the linear statics of the engine hood model under different working conditions, and to establish a collision simulation model that reflects the nonlinear collision of the engine hood model, so as to form a design area model based on the working condition model and the collision simulation model; the equivalent module 530 is used to determine the displacement matrix of the collision simulation model, and based on the displacement matrix, the collision simulation model is equivalent to a new working condition model that characterizes the static load; the optimization module 540 is used to perform topological optimization on the new working condition model, obtain a new design area model, and generate the optimal force transmission path in the engine hood model according to the new design area model.

[0082] It should be noted that the force transmission path optimization system for a lightweight engine hood provided in the above embodiment and the force transmission path optimization method for a lightweight engine hood provided in the above embodiment are based on the same concept, wherein the specific manner in which each module and unit performs operations has been described in detail in the method embodiment and will not be repeated here. In actual applications, the force transmission path optimization system for a lightweight engine hood provided in the above embodiment can allocate the above functions to different functional modules as needed, that is, divide the internal structure of the device into different functional modules to complete all or part of the functions described above, and this is not limited here.

[0083] An embodiment of the present application also provides an electronic device, comprising: one or more processors; a storage device for storing one or more programs, which, when executed by one or more processors, enables the electronic device to implement the force transmission path optimization method of the lightweight engine hood provided in the above-mentioned embodiments.

[0084] Figure 6 The following is a schematic diagram showing the structure of a computer system suitable for implementing an electronic device according to an embodiment of the present application. Figure 6 The computer system 600 of the electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0085] like Figure 6 As shown, the computer system 600 includes a central processing unit (CPU) 601, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 602 or the program loaded from the storage part 608 into the random access memory (RAM) 603, such as executing the methods provided in the above-mentioned various embodiments. Various programs and data required for system operation are also stored in the RAM 603. The CPU 601, ROM 602 and RAM 603 are connected to each other via a bus 604. An input / output (I / O) interface 605 is also connected to the bus 604.

[0086] The following components are connected to the I / O interface 605: an input section 606 including a keyboard, a mouse, and the like; an output section 607 including devices such as a cathode ray tube (CRT), a liquid crystal display (LCD), and a speaker; a storage section 608 including a hard disk and the like; and a communication section 609 including a network interface card such as a LAN (Local Area Network) card or a modem. The communication section 609 performs communication processing via a network such as the Internet. A drive 610 is also connected to the I / O interface 605 as needed. Removable media 611, such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, is installed in the drive 610 as needed, so that computer programs read therefrom can be installed into the storage section 608 as needed.

[0087] In particular, according to an embodiment of the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network via the communication section 609, and / or installed from a removable medium 611. When the computer program is executed by the central processing unit (CPU) 601, the various functions defined in the system of the present application are executed.

[0088] It should be noted that the computer-readable medium shown in the embodiments of the present application may be a computer-readable signal medium or a computer-readable storage medium or any combination of the two. The computer-readable storage medium may be, for example, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or component, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to, an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, which carries a computer-readable computer program. This propagated data signal may take a variety of forms, including but not limited to an electromagnetic signal, an optical signal, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium that can transmit, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. A computer program embodied on a computer-readable medium may be transmitted using any suitable medium, including but not limited to wireless, wired, or any suitable combination thereof.

[0089] The flowcharts and block diagrams in the accompanying drawings illustrate the possible implementation architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present application. Among them, each box in the flowchart or block diagram can represent a module, program segment, or part of the code, and the above-mentioned module, program segment, or part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart, can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0090] The units involved in the embodiments described in this application may be implemented by software or hardware, and the units described may also be set in a processor. In some cases, the names of these units do not constitute limitations on the units themselves.

[0091] Those skilled in the art will readily conceive of other embodiments of the present application after considering the specification and practicing the embodiments disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present application that follow the general principles of this application and include common knowledge or customary techniques in the art that are not disclosed herein.

[0092] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, any equivalent modifications or alterations accomplished by a person of ordinary skill in the art without departing from the spirit and technical concepts disclosed in this application shall be covered by the claims of this application.

Claims

1. A method for optimizing the force transmission path of a lightweight engine hood, characterized in that: include: Build a lightweight engine hood model; Establishing a working condition model that characterizes the linear statics of the engine hood model under different working conditions, and establishing a collision simulation model that reflects the nonlinear collision of the engine hood model, so as to form a design region model based on the working condition model and the collision simulation model; determining a displacement matrix of the collision simulation model, and converting the collision simulation model into a new working condition model representing a static load based on the displacement matrix; Topology optimization is performed on the new working condition model to obtain a new design region model, and an optimal force transmission path is generated in the engine hood model according to the new design region model.

2. The method for optimizing the force transmission path of a lightweight engine hood according to claim 1, characterized in that: Build a lightweight engine hood model, including: Obtaining a finite element mesh model including an engine hood, a front cabin structure, and a firewall, and obtaining material property parameters of the engine hood, wherein the material property parameters include elastic modulus, Poisson's ratio, and density; determining constraint boundary conditions of the finite element mesh model based on the hinge mounting points, the latch mounting points, and the contact area between the hood and the front cabin structure; The preset reinforcement plate area in the finite element mesh model is filled according to the material property parameters of the engine hood to construct the engine hood model.

3. The method for optimizing the force transmission path of a lightweight engine hood according to claim 2, characterized in that: A linear static working condition model is established to characterize the engine hood model under different working conditions, including: Establishing a collision equivalent working condition model by applying an equivalent static load at a first preset evaluation point on the engine hood; Establishing a bending stiffness working condition model by fixing the hinge mounting point of the engine hood and applying a first moment to the latch mounting point of the engine hood; Establishing a torsional stiffness operating condition model by fixing a hinge mounting point on a first side of the hood and applying a second moment to a second side of the hood, the first side of the hood being an opposite side of the second side of the hood; Establishing an anti-dent condition model by applying a normal force at a second preset evaluation point in a preset reinforcement plate area; By performing modal analysis on the engine hood, a bending modal model and a torsional modal model are established.

4. The method for optimizing the force transmission path of a lightweight engine hood according to claim 3, characterized in that: Determining a displacement matrix of the collision simulation model, and converting the collision simulation model into a new working condition model representing a static load based on the displacement matrix, including: Performing dynamic nonlinear analysis on the collision simulation model to obtain the displacement matrix; The linear stiffness matrix is calculated based on the element density of each element in the design area; Calculating an equivalent static load according to the displacement matrix and the linear stiffness matrix; The equivalent static load is applied to the collision equivalent working condition model to convert the collision simulation model into a new collision equivalent working condition model.

5. The method for optimizing the force transmission path of a lightweight engine hood according to any one of claims 1 to 4, characterized in that: The collision simulation model is equivalent to a new working condition model representing a static load based on the displacement matrix, further comprising: The displacement matrix is extracted once at a preset interval, and the corresponding equivalent static load is calculated based on the extracted displacement matrix, so as to equate the collision simulation model to a new working condition model that characterizes the static load through the moving time window technology and the equivalent static load method.

6. The method for optimizing the force transmission path of a lightweight engine hood according to any one of claims 1 to 4, characterized in that: Topology optimization of new working case models, including: The cell density of each cell in the design area is determined as a design variable, the weighted compliance sum of the first preset evaluation point in the new collision equivalent working condition model is determined as an optimization target, and the constraint condition is determined based on the bending stiffness obtained from the bending stiffness working condition model, the torsional stiffness obtained from the torsional stiffness working condition model, the displacement of the second preset evaluation point in the anti-dent working condition model, the bending mode obtained from the bending mode working condition model, the bending mode obtained from the torsional mode working condition model, and the number of cells with a current density equal to the preset density and the total number of cells. The solid isotropic material penalty model is used for iterative solution, and the adjoint variable method is used for sensitivity analysis to determine the density filtering radius and the convergence criterion to complete the topology optimization.

7. The method for optimizing the force transmission path of a lightweight engine hood according to claim 6, characterized in that: Topology optimization is performed on the new working condition model to obtain a new design area model, which also includes: Topology optimization is performed on the new working condition model to obtain a topology optimization result. Design variables are updated according to the topology optimization result. The design area model is updated according to the updated design variables until the topology optimization result satisfies the convergence criterion or reaches a preset step number threshold. Then, updating of the design area model is stopped to obtain the new design area model.

8. The method for optimizing the force transmission path of a lightweight engine hood according to any one of claims 1 to 4, characterized in that: Generating an optimal force transmission path in the engine hood model according to the new design area model includes: The cell density of each cell in the design area is determined according to the design area model, and a density cloud map is generated based on the cell density of each cell in the design area to generate an optimal force transmission path in the engine hood model.

9. A force transmission path optimization system for a lightweight engine hood, characterized in that: include: A first building block is used to construct a lightweight engine hood model; a second construction module, configured to establish a working condition model representing the linear statics of the engine hood model under different working conditions, and to establish a collision simulation model reflecting the nonlinear collision of the engine hood model, so as to form a design region model based on the working condition model and the collision simulation model; an equivalent module, configured to determine a displacement matrix of the collision simulation model, and to convert the collision simulation model into a new working condition model representing a static load based on the displacement matrix; The optimization module is used to perform topology optimization on the new working condition model to obtain a new design area model, and generate an optimal force transmission path in the engine hood model according to the new design area model.

10. An electronic device, characterized in that: The electronic device comprises: one or more processors; A storage device for storing one or more programs, which, when executed by the one or more processors, enables the electronic device to implement the force transmission path optimization method for a lightweight engine hood as described in any one of claims 1 to 8.

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