CN114462145B - Frame structure crashworthiness and lightweight design method for formula car - Google Patents
Frame structure crashworthiness and lightweight design method for formula car Download PDFInfo
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Abstract
The invention belongs to the technical field of structural optimization design, and particularly relates to a method for designing crashworthiness and light weight of a frame structure of an equation motorcycle race. The core of the technical scheme of the invention is that by selecting a proper main node, the structural nonlinear collision dynamics model related to the structural design of the formula car frame is converted into a linear statics model by applying the reduced-order equivalent static load calculation method provided by the invention, and the crashworthiness and the light-weight collaborative design of the car frame structure are realized by applying the topology optimization theory, so that the development period of the car frame structure design is shortened, and the design precision and the comprehensive performance of the car frame structure are improved.
Description
Technical Field
The invention belongs to the technical field of structural optimization design, and particularly relates to a method for designing crashworthiness and light weight of a frame structure of an equation motorcycle race.
Background
The Chinese equation automobile racing is initiated by the Chinese automobile engineering society in 2010 at the earliest time, and aims to cultivate the automobile design, manufacturing and testing capability of college students, and the large racing rule requires that a racing team independently design and manufacture a small single-seat racing car within one year, and examine the performance of accelerating, braking, turning and the like of the racing car. The event requires that the frame structure has enough crashworthiness, prevents the cabin from being extruded, further causes damage to a rider, and simultaneously reduces the damage degree to the frame structure when the front collision occurs. By analyzing the rules of the racing car, the probability of collision of the racing car on a high-speed obstacle avoidance project is greatest, and the probability of rear-end collision and side turning during the racing is smaller, so that structural crashworthiness of 100% frontal collision is the most concerned. Along with the continuous rising of the attention of energy conservation and emission reduction in the automobile industry, the automobile light weight performance is also used as an important investigation index in the equation of university of China. Therefore, the optimization design research of the crashworthiness of the frame structure is carried out under the condition of ensuring the light weight requirement of the structure, which not only meets the original purpose of the equation of university of China, but also plays an important role in improving the ecological environment, relieving the energy crisis and improving the safety performance of the vehicle. Research shows that certain contradiction and competition exist between structural crashworthiness and light weight, and crashworthiness optimization can be realized on the premise that the structural meets the light weight requirement only by considering the crashworthiness and the light weight requirement of the structure in the structural optimization design process. Structural collision topology optimization is a conceptual design method which can meet the requirements of structural crashworthiness and light weight in the field of structural optimization design. However, structural collision topological optimization belongs to a typical structural nonlinear dynamic response optimization problem, relates to high nonlinearity such as materials, geometry, contact and other complex dynamic processes such as collision impact and the like, and is one of the most complex research problems in the field of structural optimization design at present. Therefore, in the process of structural optimization design, structural crashworthiness is only used as a verification index to evaluate the safety of the structure, and the structural design requirement of the current formula car cannot be met.
The space truss type frame structure is widely adopted in the formula racing car, the successful cases of the previous frame and subjective experience of a designer are mainly evaluated aiming at the design of the structure, the crashworthiness of the structure is generally considered through redundant design, materials cannot be fully applied, and the economical efficiency and the dynamic property of the racing car are seriously affected. Therefore, the existing design method for the frame structure of the formula car mainly has the following disadvantages:
(1) The existing design method is mostly based on experience of a designer, and a novel frame structure is developed on the basis of the original structure, so that the performance of the novel structure is limited to be improved, and meanwhile, the material waste and the weight of the whole vehicle are caused;
(2) The existing design method is rarely developed based on the modern optimal design theory, and the improvement of the racing car frame in the design process is completed through trial-and-test analysis, so that the cost and period of the structural design and development of the frame are further increased;
(3) The existing design method mainly provides theoretical basis for improved design of the structure through a finite element analysis method, and conceptual optimization design considering structural crashworthiness is not developed on the basis of a finite element model. For example, the Chinese patent application number is: 201810022680.5, publication date is: the invention patent of 2018, 06 and 15 discloses a frame structure finite element analysis method of an equation motorcycle race, which provides a theoretical basis for the improved design of the structure, can solve the problem which cannot be solved by the traditional trial-and-test method, improves the design efficiency and reduces the design cost. However, the method does not extend the structure optimization design technology to the development process of the frame considering the structural crashworthiness, so as to form an efficient structure optimization design method.
(4) When the structural optimization design of the formula car is carried out, only the static performance (static strength, maximum deformation and the like) and the dynamic parameters (such as modal parameters and the like) of the structure are considered, and structural crashworthiness optimization design work involving nonlinear and dynamic response is not carried out, so that the crashworthiness of the structure is only passively checked as a checking index of the structure, the structural optimization design process is not integrated, and the structural optimization efficiency is low or the crashworthiness of the structure cannot be guaranteed.
(5) The prior method for designing the frame structure of the formula car takes the light weight performance of the structure into consideration by using a topology optimization method in the structural concept stage, but structural crashworthiness is not involved in structural topology optimization. For example, the Chinese patent application number is: 201910117880.3, publication date is: the invention patent of 2019, 07 and 05 discloses a lightweight design method of an equation motorcycle race frame, which utilizes man-machine parameters and whole motorcycle parameters to combine with a large-race rule to build a frame main body model, performs topology optimization and size optimization on the frame main body model, and realizes lightweight design on the premise of meeting the structural comprehensive torsional rigidity and the large-race rule. The invention solves the problem that the lightweight design of the prior formula car frame does not have clear evaluation indexes, but does not consider the crashworthiness, rigidity and lightweight performance of the car frame structure from the viewpoint of structural optimization, so that the crashworthiness of the structure cannot be directly ensured or improved.
Disclosure of Invention
The invention aims to provide an crashworthiness and lightweight design method for a space truss type frame structure of an equation motorcycle race, which can effectively improve the crashworthiness of the structure on the premise of considering the lightweight level of the structure, and further improve the safety of the structure on the premise of considering the economical efficiency and the dynamic property of the motorcycle race.
The technical scheme of the invention is as follows:
the method for designing the crashworthiness and the light weight of the frame structure of the formula car comprises the following steps:
s1, preparing a model: establishing a nonlinear dynamics collision finite element model, selecting a main node degree of freedom and setting control parameters (unit control and energy control) and output parameters (energy output and displacement output); meanwhile, establishing a linear statics model with the same main node degree of freedom, setting a model reduced-order working condition, and setting an output reduced-order stiffness matrix;
the control equation of the nonlinear dynamical collision model is as follows:
in the method, in the process of the invention,and x N (t) represents acceleration, velocity and displacement vectors, M (b), C (b) and K, respectively N (b,x N (b) Respectively representing a mass matrix, a damping matrix and a stiffness matrix of the structure, which are all functions of the relative density b of the units, f (t) representing an external force vector, and subscript N representing nonlinearity;
the specific theory of the model reduced order analysis is as follows:
the following displacement vectors are defined:
wherein X is a linear displacement vector, wherein X m The displacement vector is a main node degree of freedom, which refers to the degree of freedom that needs to be reserved when model reduction is performed, and the common node degree of freedom defined between a design area and a non-design area is the main node degree of freedom (hereinafter usedThe symbol m); x is X s The displacement vector is a slave node degree of freedom, wherein the slave node degree of freedom is a degree of freedom which needs to be reduced when model reduction is carried out, namely, other degrees of freedom (denoted by subscript s) except the master node degree of freedom;
at this time, the statics balance equation k·x=f can be expressed as a block matrix form as follows:
wherein K is a linear stiffness matrix, F is a node static displacement vector, F m And F s Static displacement vectors acting on the degrees of freedom of the master node and the degrees of freedom of the slave node respectively; according to the matrix algorithm, the stiffness matrix K can be expressed as a segmented matrix form as described above, then K mm And K ss The rigidity matrix blocks respectively correspond to the degrees of freedom of the master node and the degrees of freedom of the slave node; k (K) ms And K sm The mixed matrix corresponding to the degrees of freedom of the master node and the degrees of freedom of the slave node are divided into blocks, and the mixed matrix is a symmetrical matrix according to the elastic mechanics theory K, so that the mixed matrix has
Based on the model order reduction theory, the equilibrium equation of the order reduction model is expressed as:
K red ·X m ＝F red
wherein F is red To act only on the equivalent load of the primary node degree of freedom, K red For the reduced stiffness matrix, it can be expressed specifically as:
s2, model analysis: the nonlinear dynamics (collision) model established in the S1 is used for carrying out structural collision analysis and obtaining structural collision energy response E (t) and displacement response vector x (t); meanwhile, on the basis of the linear statics model established in the step S1, the model is carried outObtaining a rigidity matrix K by reduced order analysis R 。
S3, model equivalence: on the basis of S2, defining the moment of maximum energy in the structural collision energy response E (t) as a key time point t c And outputs displacement vector x of the degree of freedom of the main node of the structure at the moment Nm (t c ) Further equivalent complex collision dynamics process to correspond to the key time point t c And only acts on the reduced-order equivalent static load F of the degree of freedom of the main node red (L c )
F red (L c )＝K R ·x Nm (t c )
Wherein x is Nm (t c ) Corresponding to the critical point in time t in the displacement response in S2 c A displacement vector of the degree of freedom of the master node;
s4, topology optimization: based on the equivalent static model established in the step S3, taking the unit relative density b as a design variable, the flexibility g (b) minimum as an objective function and the volume V as a constraint, establishing a topological optimization model considering both structural crashworthiness and light weight as follows:
find:b∈R n
to min:g(b)
subject to:K(b)X(L c )＝F red (L c ),c＝1,...,q
v T b≤V
0.0＜b min ≤b i ≤1.0,i＝1,...,n
where g (b) is the structural compliance corresponding to the equivalent static model in S3, K (b) is the structural stiffness matrix corresponding to the linear model in S3, X (L c ) To correspond to the key time point t c Is equivalent to static load F red (L c ) A displacement vector under action; b min Is the minimum value of the relative density (design variable) of the unit, and is used for preventing the unit stiffness matrix from generating singular;
s5, variable updating and model reconstruction: judging the convergence of the optimization process according to the objective function value and the relative variable quantity of the design variables in the two adjacent optimization processes, calling out the optimization process if the convergence is carried out, and updating the model to the step S1 if the convergence is not carried out, wherein the model updating is carried out by coupling the corresponding design area in the collision model into the collision model in a superunit mode for collision analysis again, so that the model reconstruction analysis is realized.
The beneficial effects of the invention are as follows:
(1) The method comprehensively considers the crashworthiness and the light weight performance of the frame structure of the formula car in the conceptual design stage, and effectively improves the performance and the design efficiency of the structure;
(2) According to the method, the degree of freedom of the main node is reasonably selected, and the model reconstruction collision model after variable updating is subjected to reduced-order processing, so that the collision analysis cost can be effectively reduced, and the phenomenon of unstable numerical value caused by the problems of grid distortion and the like is avoided;
(3) The method disclosed by the invention has the advantages that the equivalent static load acting on all node degrees of freedom in the design domain is equivalently transferred to the degree of freedom of the main node, so that the problem of difficulty in optimizing and converging caused by the node characteristics of the equivalent static load is well solved;
(4) When the structure is optimized under the action of the reduced equivalent static load, the method can reduce the order of the structure outside the optimized design area and couple the structure to the structure optimization model in the form of superunit, thereby further reducing the optimization cost and improving the optimization efficiency;
(5) The method has the advantages that any low-density unit is not deleted when the model is updated, the internal degree of freedom of a design area where the low-density unit is located is reduced, and the output rigidity matrix is coupled into the collision model in a superunit mode, so that the problem of unstable numerical value caused by the low-density unit in the collision analysis process is avoided, the consistency of a topology optimization result and the collision analysis model is ensured to the greatest extent, and the convergence of the topology optimization result is improved;
(6) The method can fully utilize the advantages of the existing mature commercial software platform, realize the collaborative optimization design of the formula car structure, and is easy to realize programming and popularization and application;
(7) The method balances the competition and conflict between the structural crashworthiness and the lightweight performance, expands the application range of the structural optimization method, shortens the design period of the frame structure of the formula car and improves the accuracy of the optimization design.
Drawings
FIG. 1 is a flow chart of a structural crashworthiness and lightweight design method of the present invention.
FIG. 2 is a finite element model of an original frame structure collision of the formula car.
FIG. 3 is a diagram of an initialization design model for the front end structure of the racing car.
Fig. 4 shows the topology optimization result of the front end structure of the racing car.
FIG. 5 is a schematic diagram of an optimal frame construction of a formula car.
FIG. 6 is a comparison of the intrusion of a front collision between a new frame structure and an original frame structure.
Fig. 7 is a comparison of crashworthiness and lightweight performance of the novel frame structure versus the original structure.
FIG. 8 is a schematic diagram of an optimized formula car.
Detailed Description
The present invention will be described in detail with reference to the accompanying drawings.
In a collision accident of formula car, the front collision is most likely to cause excessive intrusion of the front end structure of the car frame and damage to the legs of the rider, so that the front end structure needs to be particularly focused on crashworthiness when designing the formula car frame. However, because of the competition and conflict between crashworthiness and weight reduction of the formula car frame structure, cooperative consideration in the structural optimization design is necessary.
The method is characterized in that a structural nonlinear collision dynamics model related to the structural design of the formula car frame is converted into a linear statics model by selecting proper degree of freedom of a main node and applying the reduced equivalent static load calculation method provided by the invention, and the crashworthiness and light-weight collaborative design of the car frame structure are realized by applying a topology optimization theory, so that the development period of the car frame structure design is shortened, and the design precision and the comprehensive performance of the car frame structure are improved. The method provided by the invention comprises the steps of model preparation, model analysis, model equivalence, topology optimization, variable updating, model reconstruction and convergence judgment, and is specifically described as follows:
1. model preparation
As shown in fig. 1, a flow chart of an crashworthiness and lightweight design method of a frame structure of an equation motorcycle race provided by the invention is shown, firstly, a nonlinear collision finite element model of a frame structure of an original equation motorcycle race shown in fig. 2 is established, a common node between a design area and a non-design area is defined as a main node, all degrees of freedom of the common node are selected as main node degrees of freedom, and control parameters (unit control and energy control) and output parameters (energy output and displacement output) are set; meanwhile, by initializing the designed area, a linear statics model shown in fig. 3 is built, model order-reduction working conditions are set, and an output order-reduction stiffness matrix is set.
2. Model analysis
On the one hand, on the basis of a nonlinear collision finite element model, a structural collision simulation is carried out in a model analysis module, structural collision energy response E (t) and displacement response vector x (t) are output, and the crashworthiness and load transmission path of the original structure are analyzed; meanwhile, the structure is subjected to model order reduction, and an order-reduced rigidity matrix K of the corresponding structure is output R 。
3. Model equivalent
In the invention, the moment of maximum internal energy in the structural collision energy response E (t) is defined as a key time point t c And outputs a displacement vector x of the degree of freedom of the structural main node at the moment Nm (t c ) Then the complex collision dynamics process is equivalent to be corresponding to the key time point t c And only acts on the reduced-order equivalent static load F of the degree of freedom of the main node red (L c )：
F red (L c )＝K R ·x Nm (t c )
On the basis of the structural linear statics model established in the step 1, the invention provides the reduced equivalent static load F red (L c ) Establishment ofAnd the equivalent static load working condition is equivalent, and the equivalent linear static conversion of the collision model is realized. Finally, on the basis of the equivalent static model, defining a minimum value b of the relative density with the unit relative density b as a design variable, the compliance g (b) minimum as an objective function, the volume V as a constraint min Is described.
4. Topology optimization
The specific mathematical model of the structural topology optimization model established in the step 3 is as follows:
find:b∈R n
to min:g(b)
subjectto:K(b)X(L c )＝F red (L c ),c＝1,...,q
v T b≤V
0.0＜b min ≤b i ≤1.0,i＝1,...,n
wherein g (b) corresponds to the structural compliance of the equivalent static model in the third step, K (b) is a structural stiffness matrix corresponding to the linear model, X (L) c ) To correspond to the key time point t c Is equivalent to static load F red (L c ) Displacement vector under action.
5. Variable update and model reconstruction
Judging the convergence of the optimization process according to the objective function value and the relative variable change quantity of the design variables in the two adjacent optimization processes, calling out the optimization process if the convergence is carried out, and updating the model to the step S1 if the convergence is not carried out, wherein the model updating is carried out by carrying out model order reduction processing on the corresponding design area in the collision model, and coupling the obtained order reduction stiffness matrix into the collision model in a superunit mode for carrying out collision analysis again so as to realize model reconstruction.
Examples
Taking the frame structure of formula car shown in fig. 2 as an example, a collision finite element model was built to simulate a 200kg formula car striking a rigid wall in the axial direction at a speed of 2 m/s. During modeling, two node units with the front end size of 10mm and the rear end size of 50mm are selected for grid division, wherein the materials are respectively 210000Mpa, 0.33 and 7.9x10 in Young modulus, poisson's ratio and density -9 T/mm 3 The steel product has a tangential modulus of 107GPa and a yield stress of 340MPa.
Based on the above collision finite element model, the crashworthiness of the structure and the load transmission path are analyzed by collision simulation. As a result, it has been found that the topological layout of the space truss structure is not reasonable, which results in unsmooth load transfer during a frontal collision of the formula car, and the front end structure has a large intrusion amount, which is liable to cause damage to the legs of the rider. In order to improve the crashworthiness of the structure and simultaneously consider the lightweight performance of the structure, the front end structure of the formula car shown in fig. 2 is taken as a design area, and the structural optimization design method provided by the invention is utilized for carrying out topology reconstruction.
As shown in fig. 3, the design model is initialized by the front end structure of the equation racing car, the area of the design area with the constraint upper limit of 0.2 times is set, the minimum relative density of units is 0.001, all degrees of freedom of common nodes of the design area and the non-design area in the model are selected as main node degrees of freedom, model reduction is performed on the non-design area, and a rigidity matrix is output. The reduced-order equivalent static load calculation method provided by the invention is utilized, and an equivalent static topological optimization model is formed by combining an established linear static model.
The optimal topological density distribution diagram shown in fig. 4 is obtained by carrying out topological optimization analysis on the model, and the graph shows that the high-density region is mainly distributed near the longitudinal direction and the four edges, so that the load transmission capacity of the structure is improved, the load transmission path is reasonable and reliable, and the efficient and steady transmission of collision load is facilitated. In addition, in order to meet the light weight requirement (volume constraint), the structure is symmetrically distributed, 5 triangular low-density areas are formed on two sides of the structure, and the topological layout is beneficial to reducing stress concentration and improving the robustness of the structure on the premise of ensuring the bearing capacity of the structure. After engineering interpretation and process correction, the topology of the optimized model obtained by geometric modeling is shown in fig. 5.
In order to verify the effectiveness of the method, the structure obtained by topological optimization is remodelled, and collision analysis as shown in fig. 2 is carried out again under the same condition, and the crashworthiness of the optimized model is evaluated by comparing with the original structure. Fig. 6 shows the comparison of the intrusion amount of the front collision of the novel frame structure and the original frame structure, and by comparing the intrusion amount-time curves of the two models, the intrusion amount of the front end of the novel model can be found to be reduced to different degrees in the whole collision process, so that the living space of a rider is effectively ensured. In order to further comprehensively evaluate the crashworthiness and the lightweight performance of the novel frame structure, the crashworthiness and the lightweight performance of the novel frame structure are compared with those of the original structure as shown in fig. 7, and the maximum intrusion of the front end structure is reduced by 24.1% under the condition that the structural quality of the novel structure is reduced by 0.07%. In summary, the method for designing the crashworthiness and the light weight of the frame structure of the formula car provided by the invention can obviously improve the crashworthiness of the structure on the premise of considering the light weight requirement of the structure, effectively reduce the development period of the frame of the formula car and improve the structural optimization design efficiency. FIG. 8 shows the improved design of the formula racing car by the method of the invention.
Claims (3)
1. The method for designing the crashworthiness and the light weight of the frame structure of the formula car is characterized by comprising the following steps of:
s1, preparing a model: establishing a nonlinear dynamics collision finite element model, selecting the degree of freedom of a main node, and setting control parameters and output parameters; meanwhile, establishing a linear statics model with the same main node degree of freedom, setting a model reduced-order working condition, and setting an output reduced-order stiffness matrix;
the control equation for the nonlinear dynamical collision model is as follows:
in the method, in the process of the invention,and x N (t) represents acceleration, velocity and displacement vectors, M (b), C (b) and K, respectively N (b,x N (b) Respectively representing the structure qualityThe damping matrix and the stiffness matrix are functions of the relative density b of the units, f (t) represents an external force vector, and subscript N represents nonlinearity;
the specific theory of model order reduction analysis is as follows:
the following displacement vectors are defined:
wherein X is a linear displacement vector, wherein X m The displacement vector is a displacement vector of a main node degree of freedom, wherein the main node degree of freedom refers to the degree of freedom which needs to be reserved when model reduction is carried out; x is X s The displacement vector is a slave node degree of freedom, wherein the slave node degree of freedom is the degree of freedom which needs to be reduced when model reduction is carried out;
at this time, the statics balance equation k·x=f is expressed as a block matrix form as follows:
wherein K is a linear stiffness matrix, F is a node static displacement vector, F m And F s Static displacement vectors acting on the degrees of freedom of the master node and the degrees of freedom of the slave node respectively; according to the matrix algorithm, the stiffness matrix K is expressed as a segmented matrix form as described above, then K mm And K ss The rigidity matrix blocks respectively correspond to the degrees of freedom of the master node and the degrees of freedom of the slave node; k (K) ms And K sm The mixed matrix corresponding to the degrees of freedom of the master node and the degrees of freedom of the slave node are divided into blocks, and the block is a symmetrical matrix according to the elastic mechanics theory K, and has
Based on the model order reduction theory, the equilibrium equation of the order reduction model is expressed as:
K red ·X m ＝F red
wherein F is red To act only on the equivalent load of the primary node degree of freedom, K red For the reduced stiffness matrix, it can be expressed specifically as:
s2, model analysis: the nonlinear dynamics collision model established in the S1 is used for carrying out structural collision analysis and obtaining structural collision energy response E (t) and displacement response vector x (t); meanwhile, on the basis of the linear statics model established in the step S1, model reduced-order analysis is carried out to obtain a rigidity matrix K R ；
S3, model equivalence: on the basis of S2, defining the moment of maximum energy in the structural collision energy response E (t) as a key time point t c And outputs displacement vector x of the degree of freedom of the main node of the structure at the moment Nm (t c ) Further equivalent complex collision dynamics process to correspond to the key time point t c And only acts on the reduced-order equivalent static load F of the degree of freedom of the main node red (L c )
F red (L c )＝K R ·x Nm (t c )
Wherein x is Nm (t c ) Corresponding to the critical point in time t in the displacement response in S2 c A displacement vector of the degree of freedom of the master node;
s4, topology optimization: based on the equivalent static model established in the step S3, taking the unit relative density b as a design variable, the flexibility g (b) minimum as an objective function and the volume V as a constraint, establishing a topological optimization model considering both structural crashworthiness and light weight as follows:
find:b∈R n
to min:g(b)
subject to:K(b)X(L c )＝F red (L c ),c＝1,...,q
v T b≤V
0.0＜b min ≤b i ≤1.0,i＝1,...,n
wherein g (b) is the correspondingStructural compliance of the equivalent static model in S3, K (b) is a structural stiffness matrix corresponding to the linear model in S3, X (L c ) To correspond to the key time point t c Is equivalent to static load F red (L c ) A displacement vector under action; b min Is the minimum value of the relative density of the unit and is used for preventing the unit stiffness matrix from generating singular;
s5, variable updating and model reconstruction: judging the convergence of the optimization process according to the objective function value and the relative variable quantity of the design variables in the two adjacent optimization processes, calling out the optimization process if the convergence is carried out, and updating the model to the step S1 if the convergence is not carried out, wherein the model updating is carried out by coupling the corresponding design area in the collision model into the collision model in a superunit mode for collision analysis again, so that the model reconstruction analysis is realized.
2. The formula car frame structure crashworthiness and lightweight design method of claim 1, wherein the master node degrees of freedom are defined as common node degrees of freedom between design and non-design areas.
3. The method of claim 2, wherein the slave node degrees of freedom are defined as degrees of freedom other than the master node degrees of freedom.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210100513.4A CN114462145B (en) | 2022-01-27 | 2022-01-27 | Frame structure crashworthiness and lightweight design method for formula car |
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| KR20110023096A (en) * | 2009-08-28 | 2011-03-08 | 주식회사 프릭사 | Light weight brake disk for sports and racing car |
| CN103612688A (en) * | 2013-11-28 | 2014-03-05 | 宁波跃进汽车前桥有限公司 | Automobile chassis part weight reduction method based on multi-body dynamics and topological optimization technology |
| CN106126849A (en) * | 2016-07-04 | 2016-11-16 | 上海迅仿工程技术有限公司 | The non-linear Topology Optimization Method that a kind of vehicle body solder joint is arranged |
| CN109977461A (en) * | 2019-02-15 | 2019-07-05 | 江苏大学 | A kind of equation motorcycle race vehicle frame light-weight design method |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20110023096A (en) * | 2009-08-28 | 2011-03-08 | 주식회사 프릭사 | Light weight brake disk for sports and racing car |
| CN103612688A (en) * | 2013-11-28 | 2014-03-05 | 宁波跃进汽车前桥有限公司 | Automobile chassis part weight reduction method based on multi-body dynamics and topological optimization technology |
| CN106126849A (en) * | 2016-07-04 | 2016-11-16 | 上海迅仿工程技术有限公司 | The non-linear Topology Optimization Method that a kind of vehicle body solder joint is arranged |
| CN109977461A (en) * | 2019-02-15 | 2019-07-05 | 江苏大学 | A kind of equation motorcycle race vehicle frame light-weight design method |
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