Crash model analysis method

Abstract

The present invention relates to a method for analyzing a vehicle collision using a simplified model for vehicle collision model analysis based on finite element analysis using software to analyze a vehicle collision, the method including: a first region setting step in which a first region where deformation occurs due to a collision is defined in a first input unit, and modeling for the first region is input and stored in a storage unit; a second region setting step in which a second region where deformation is relatively small due to a collision is defined in a second input unit, and the second region is designated as a steel element, and simplified information on the steel element is input and stored in the storage unit; a correction step in which a boundary between the first region and the second region is designated as a first beam element in a correction unit, and one end of the first beam element is connected to the modeling and the other end is connected to the steel element and stored; and an analysis step in which a calculation unit automatically calculates the collision through a finite element analysis algorithm using the values ​​stored in the storage unit and the correction unit.

Description

Technical Field

[0001] The present invention relates to a method for analyzing a vehicle collision using a simplified model in vehicle collision model analysis based on finite element analysis using software for analyzing a vehicle collision.

Background Art

[0002] Collision tests are being conducted using a vehicle frontal collision evaluation method for the reliability of components and vehicles against vehicle collisions.

[0003] The full frontal collision test (Full Rigid Barrier, FRB) is a test regulation for colliding a vehicle with a completely fixed wall, and is conducted in a manner of colliding with a wall fixed at a speed of 48 km / h or 56 km / h.

[0004] The offset deformable barrier test is a test in which a part (40%) of the front part of the vehicle is collided with a fixed wall at a speed of 64 km / h. When the full frontal collision test is handled by two front side members, this test is handled by a part.

[0005] The small overlap front collision test is a test in which a very small part (about 25%) of the front part of the vehicle is collided with a fixed wall at 64 km / h. This is a method of confirming the reliability of a vehicle against a collision by almost detaching the front side member and usually inserting a structure connected to the front side member or detaching it during a collision to transmit a minimum impact to the occupant.

[0006] The above collision tests are applied as main evaluation criteria during vehicle development. In the vehicle development stage of an automobile company, in order to develop a vehicle that meets this evaluation criteria, it is judged whether the corresponding criteria are satisfied through collision analysis based on the finite element method for all vehicles.

[0007] Through this type of crash analysis, in addition to the overall performance of the vehicle, the crash performance of the vehicle's components is evaluated to determine the direction of improvement and the degree of impact of those improvements.

[0008] While some are developing design techniques using simplified analysis models rather than full-vehicle crash analysis models, the results are inferior to those of full-vehicle crash analysis, limiting their applicability to actual parts development. Furthermore, in electric vehicles, crash testing has become a crucial element for battery safety. Therefore, there is a need for crash analysis methods that allow parts manufacturers to perform accurate crash tests quickly. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] Korean Published Patent No. 10-2018-0009904 (Published January 30, 2018) [Overview of the Initiative] [Problems that the invention aims to solve]

[0010] The present invention aims to solve the above-mentioned problems and to provide a crash model analysis method that can simulate crash tests using a simplified model rather than a model of all vehicles. [Means for solving the problem]

[0011] To achieve the above objective, the present invention provides a method for analyzing a collision model formed as follows.

[0012] A collision model analysis method according to one embodiment of the present invention is a vehicle collision model analysis method based on finite element analysis using software, comprising: a first region setting step in which a first region, which is a region where deformation occurs due to collision, is defined in the first input section, and a model for the first region is input and saved in the storage section; and a second region, which is a region where deformation is relatively small due to collision, is defined in the second input section, and the second region is Rigid body It is specified as an element, and the above Rigid body A second region setting step in which simplified information for the element is input and saved in the storage unit, and a first beam element is designated in the correction unit at the boundary between the first region and the second region, one end of the first beam element is connected to the modeling, and the other end is connected to the above Rigid body The system includes a correction step, which is linked to and stored in the element, and an analysis step, in which the calculation unit automatically calculates the collision using the values ​​stored in the storage unit and the correction unit via a finite element analysis algorithm.

[0013] The above correction step may include a correction input step in which a first cross section, which is a cross section in the width direction of the vehicle, is input to a vehicle part designated as the first beam element and located at the boundary; a correction calculation step in which a first moment of inertia, which is the moment of inertia of the first cross section, is automatically calculated; and a correction storage step in which one end of the first beam element is connected to the first cross section of the model and the first moment of inertia is stored as information of the first beam element.

[0014] The first cross-section described above may be the cross-section of the front pillar (A-pillar), the rocker, and the longitudinal floor.

[0015] Located between the correction step and the analysis step, the correction unit is set as a second beam element with respect to the battery frame surrounding the battery area of ​​the vehicle, one end of the second beam element is connected to the modeling, and the other end is connected to the Rigid bodyThe process further includes a battery frame setting step which is linked to and saved as an element, the battery frame setting step which includes a side frame forming the side of the battery frame and a second cross section which is the cross section in the width direction of a battery longitudinal frame positioned in the longitudinal direction of the vehicle below the battery area as input, a battery frame calculation step which calculates a second moment of inertia which is the moment of inertia of the second cross section, and a battery frame saving step which is set and saved such that one end of the second beam element is linked to the second cross section.

[0016] The above battery frame setting step may further include a front frame setting step in which a battery front frame, positioned in the width direction of the vehicle and located in the first region, is input as a beam element and stored as a third beam element, the third beam element is set at the position of the front frame, and a third moment of inertia is calculated and stored at an arbitrary cross section of the front frame in the vehicle length direction.

[0017] The simplified information above can include the center of gravity and mass of the second region described above.

[0018] The collision in the above collision model analysis is a frontal collision, and the first region may include a portion of the battery frame.

[0019] The first region described above may include the front bumper, front subframe, and front side members of the vehicle. [Effects of the Invention]

[0020] With the configuration described above, the present invention enables simulations targeting all vehicles and analysis of collision models with high accuracy.

[0021] Furthermore, it allows for the analysis of simulations in a short amount of time.

[0022] Furthermore, it is possible to make the development of front collision analysis components for protecting electric vehicle batteries more efficient, and an effect is provided such that collision analysis can be independently performed not only by automobile companies but also by component companies.

Brief Description of Drawings

[0023] [Figure 1] It is a flowchart of an analysis method of a collision model according to an embodiment of the present invention. [Figure 2] It is a configuration diagram of an apparatus for performing an analysis method of a collision model according to an embodiment of the present invention. [Figure 3] A first region and a second region according to an embodiment of the present invention are shown. [Figure 4] A state stored in a storage unit before an analysis stage of an analysis method of a collision model according to an embodiment of the present invention is shown. [Figure 5] The position and shape of a first cross-section according to an embodiment of the present invention are shown, and cross-sections of (a) a front pillar (A-pillar), (b) a rocker, and (c) a longitudinal floor are shown. [Figure 6] The cross-section and its shape set at the battery frame setting stage according to an embodiment of the present invention are shown. (a) and (b) show cross-sections of (a) a battery side frame and (b) a battery lower longitudinal frame as a second cross-section, and (c) shows a cross-section of a battery front frame as a third cross-section.

Modes for Carrying Out the Invention

[0024] Hereinafter, specific embodiments of the present invention will be described with reference to the accompanying drawings. However, the idea of the present invention is not limited to the presented embodiments, and those skilled in the art who understand the idea of the present invention can easily propose other inventions that are regressive or other embodiments included within the scope of the idea of the present invention by adding, changing, or deleting other components within the same idea range, and this is also included within the scope of the idea of the present invention.

[0025] Furthermore, in describing the present invention, "~part" or "unit" can be implemented in various ways, such as a processor, program instructions executed by the processor, software modules, microcode, computer program products, logic circuits, application-specific integrated circuits, firmware, and the like.

[0026] The methods disclosed in the embodiments of this application can be implemented directly in a hardware processor, or in a processor through a combination of hardware and software modules. The software modules can be stored in conventional storage media such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, or registers. The storage media are located in memory, and the processor reads the information stored in memory and combines it with its hardware to complete the methods described above. To avoid redundancy, a detailed explanation is omitted here.

[0027] In the implementation process, each of the above-described steps can be completed by hardware logic integrated circuits or software-based instructions within the processor. The steps disclosed in the embodiments of this application can be implemented directly in a hardware processor, or by a combination of hardware and software modules within the processor. The software modules can be stored in conventional storage media such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, or registers. The storage media are located in memory, and the processor reads the information stored in memory and combines it with its hardware to complete the steps described above.

[0028] In other words, a person with ordinary skill in the art will see that each exemplary unit and algorithmic step described in the embodiments disclosed herein can be implemented by combining electronic hardware or a combination of computer software and electronic hardware. Whether such functions are implemented in hardware or software will depend on the specific application of the technical solution and the design constraints. A person with ordinary skill may implement the functions described using different methods for each of the specified applications, but such implementations should not be considered outside the scope of this application.

[0029] In some embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the embodiments of the apparatus described above are merely illustrative, and the division of the units described above is merely a kind of logical functional division. In actual implementation, other divisional methods may exist, for example, multiple units or assemblies may be combined or integrated into another system, or some features may be ignored or not performed. Also, the coupling or direct coupling or communication connection between elements shown or discussed may be an indirect coupling or communication connection via some interface, apparatus or unit, and may be electrical, mechanical, or otherwise.

[0030] The units described above as separated components may be physically separated, and the components shown as units may not be physical units; they may be located in one place or distributed across multiple network units. Depending on the actual needs, some or all of these units can be selected to achieve the objectives of this embodiment.

[0031] In other words, each functional unit in each embodiment of this application may be integrated into a single processing unit, each unit may exist independently, or two or more units may be integrated into a single unit.

[0032] If the above functions are implemented in the form of a software function unit and sold or used as an independent product, they can be stored on a single computer-readable storage medium. Based on this understanding, any part of the technical solution of this application that is essentially or contributes to the prior art, or any part of the above technical solution, can be implemented in the form of a software product, which is stored on a single storage medium and includes some instructions so that all or some steps of the method described in each embodiment of this application can be performed by a single computer device (which may be a personal computer, server, or network device, etc.). The storage mediums mentioned above include various media capable of storing program code, such as USB memory, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or CDROMs.

[0033] Computer-aided engineering (CAE) has been used to assist engineers in many tasks. For example, in structural or product design procedures, CAE analysis, particularly finite element analysis (FEA), has often been used to evaluate responses (e.g., stress, displacement, etc.) under various loading conditions (e.g., static or dynamic).

[0034] This invention relates to a vehicle crash analysis technique primarily applied when designing collision core components in the front of a vehicle, based on changes in vehicle component design characteristics for protecting high-capacity batteries, which are used for long-distance operation of existing internal combustion engine vehicles and eco-cars, particularly electric vehicles.

[0035] The aim is to improve design efficiency by simplifying peripheral components that effectively reflect vehicle behavior characteristics, rather than relying on the high cost and low efficiency of existing full-vehicle modeling. This is achieved through detailed modeling of core components involved in front-end collisions and the simplification of surrounding components. Furthermore, it provides an analysis method that allows for diverse approaches in the early stages of design without requiring full vehicle information.

[0036] This invention relates to a method for analyzing a vehicle collision model based on finite element analysis using software via electronic devices such as computers, and the following describes how it is operated by a mechanical device.

[0037] Figure 1 shows a simplified method according to one embodiment of the present invention, and Figure 2 shows the configuration formed according to one embodiment of the present invention. Figure 3 shows the first and second regions, Figure 4 shows the second region simplified according to one embodiment of the present invention, Figure 5 shows the shape of the first cross section S1 specified in the correction stage, and Figure 6 shows the shapes of the second cross section S2 and the third cross section in the battery frame setting stage.

[0038] A collision model analysis method according to one embodiment of the present invention includes a first region setting step S10, a second region setting step S20, a correction step S30, and an analysis step S50.

[0039] Basic information is input into input unit 1, and based on the overall shape of the vehicle, areas can be specified depending on whether the deformation due to the collision is significant or not. Then, detailed modeling is used as is for areas with large deformations, while areas where the deformation is relatively small or almost negligible are simplified and saved in storage unit 3.

[0040] In the first region setting stage S10, a first region D1, which is the region where deformation occurs due to collision, is defined in the first input unit 11, and a model for the first region D1 can be input and saved in the storage unit 3. The first region D1 can be input as is, with a model showing all configurations in detail. Information input externally can also be retrieved by the first input unit 11. The first region D1 is defined as the shape and information of the input model. Rigid bodyIt may be saved as an element.

[0041] In the second region setting step S20, a second region D2 is defined in the second input unit 12, which is a region where deformation due to collision is relatively small, and the second region D2 is Rigid body It is specified as an element, as above Rigid body Simplified information for the elements can be input and stored in the storage unit 3.

[0042] As an example, the simplified information above may include the center of gravity G and mass of the second region D2.

[0043] The second region D2 is a region that undergoes relatively little deformation in the event of a collision. Rigid body It may be input as an element or automatically set by the second input unit 12. Then, simplified information can be transmitted. The center of gravity G and mass for the second region D2 can be defined, and the second region D2 is not a model, but the center of gravity G corresponds to the mass. Rigid body It can be stored as an element in storage unit 3.

[0044] The first domain D1 and the second domain D2 combine to form the overall vehicle model domain, and the criteria for the first domain D1 and the second domain D2 may be automatically set by basic data already established through conventional experience or experimentation, or they may be directly input by the experimenter.

[0045] For example, if the modeling of all vehicles is input, the calculation unit 4 may automatically calculate the mass moment of inertia to reflect the behavioral characteristics of all vehicles, and the mass moment of inertia of the second region D2 may be automatically corrected considering the mass moment of inertia of all vehicles.

[0046] The above is divided into the first region D1 and the second region D2, and the second region D2 is Rigid body By simplifying the analysis to its constituent elements, the analytical model can be simplified and the analysis can be performed more efficiently.

[0047] When performing analysis with the simplified model described above, errors occur compared to performing analysis with the actual model that comprises the entire model. To correct for these errors, beam element B is set in a certain region, and the moment of inertia of the mass of the cross-section S to which beam element B is set is considered.

[0048] Correction step S30 is performed at the boundary between the first region D1 and the second region D2, where the first beam element B1 is designated, one end of the first beam element B1 is connected to the modeling, and the other end is connected to the Rigid body It can be saved by being concatenated to an element.

[0049] Correction step S30 is the step in which corrections are made to account for the small deformation amounts due to elasticity and partial plasticity in the simplified collision analysis of the second region D2 described above. In other words, the small deformation amounts are considered by taking into account the actual center of gravity R relative to the overall modeling.

[0050] In the correction unit 2, in order to take into account minute deformation amounts, the first beam element B1 is automatically specified or set, one end of the first beam element B1 is connected to the above modeling, and the other end is connected to the above Rigid body It may be configured to be linked to an element. The execution of the correction unit 2 as described above may be saved to the correction unit 2 at the same time as the execution. Alternatively, the contents of the execution of correction step S30 may be saved to the storage unit 3.

[0051] According to one embodiment of the present invention, the correction step S30 may include a correction input step S31, a correction calculation step S32, and a correction storage step S33.

[0052] The correction input step S31 may be specified as the first beam element B1, and the first cross section S1, which is a cross section in the width direction of the vehicle, may be input to the vehicle component located at the boundary.

[0053] The correction calculation step S32 can automatically calculate the first moment of inertia, which is the moment of inertia of the first cross-section S1.

[0054] In the correction and saving stage S33, one end of the first beam element B1 is connected to the first cross section S1 of the model, and the first moment of inertia can be saved as information of the first beam element B1.

[0055] As an example, the first section S1 described above may be a section of the front pillar, rocker, and longitudinal floor.

[0056] The first section S1 can be defined as the section of a part located at the boundary between the first region D1 and the second region D2, formed from the front part of the vehicle and connected from the rear part. Therefore, as described above, it can be a section of the front pillar, rocker, and longitudinal floor cut in the width direction of the vehicle. The section itself may be specified, or if the position is specified, the correction unit 2 may automatically specify the above section.

[0057] However, the scope is not limited to the above-mentioned components; all components located at the boundary between the first region D1 and the second region D2 can be included.

[0058] The application of beam elements allows for the representation of minute deformations in the simplified region across all degrees of freedom, thereby improving the accuracy of the representation of the entire vehicle collision behavior in the analysis model.

[0059] In the analysis stage S50, the calculation unit 4 can automatically calculate the collision using the values ​​stored in the storage unit 3 and the correction unit 2 via a finite element analysis algorithm.

[0060] For example, the collision in the above collision model analysis could be a frontal collision.

[0061] According to one embodiment of the present invention, all collisions can be simplified and analyzed. While not limited to this, the case of a frontal collision will be described below.

[0062] In the case of a frontal collision, the first region D1 may include the vehicle's front bumper, front subframe, and front side members. By including the front bumper, front subframe, and front side members, which are the components that absorb the most impact in a frontal collision, the roles of these components in a frontal collision can be fully confirmed.

[0063] As an example, the system may further include a display unit 5, which allows the result value calculated by the calculation unit 4 to be displayed through a device such as a display.

[0064] For example, the first region D1 described above may include a part of the battery frame.

[0065] In this case as well, the battery frame can be reinforced with beam elements to reflect its minute deformation characteristics in order to protect the battery.

[0066] If a portion of the battery frame is included, a battery frame setting step S40 may be further included to individually simplify and correct the battery frame.

[0067] As an example, the battery frame setting step S40 is located between the correction step S30 and the analysis step S50, and the correction unit 2 sets a second beam element B2 for the battery frame surrounding the battery area of ​​the vehicle, one end of the second beam element B2 is connected to the modeling, and the other end is connected to the Rigid body It can be saved by being concatenated to an element.

[0068] As an example, the battery frame setting step S40 may include a battery frame input step S41 into which a side frame forming the side of the battery frame and a second cross section S2 which is the cross section in the width direction of a battery longitudinal frame arranged in the longitudinal direction of the vehicle below the battery area are input; a battery frame calculation step S42 which calculates the second moment of inertia, which is the moment of inertia of the second cross section S2; and a battery frame saving step S43 which sets and saves the second cross section S2, the calculated value of the second moment of inertia, and the second beam element B2 so that one end of the second cross section S2 is connected to the second cross section S2.

[0069] The second beam element B2, like the first beam element B1, has one face connected to the detailed modeling region formed by the boundary between the first region D1 and the second region D2, and the other end is connected to the second region D2. Rigid body It may be concatenated with elements.

[0070] Furthermore, the battery frame setting step S40 may further include a front frame setting step in which a battery front frame, arranged in the width direction of the vehicle and located in the first region D1, is input as a beam element and stored in the third beam element B3, the third beam element is set at the position of the front frame, and the third moment of inertia is calculated and stored at an arbitrary cross section of the front frame in the vehicle length direction.

[0071] The front frame of the battery region does not necessarily have to be located at the boundary between the first region D1 and the second region D2. However, it can be further simplified by converting it to a beam element.

[0072] When the front frame is converted to the third beam element B3, it is not connected to a specific configuration in the second region D2, and the original fixed configuration at that position can be applied as is.

[0073] According to the present invention, the first region D1, which is the design target region, can derive accurate collision deformation behavior and collision energy values ​​through detailed modeling, similar to the analysis model of the entire vehicle. The second region D2, which is the simplified region, is simplified to the maximum extent, but is reinforced with beam element B, which has the effect of deriving collision behavior similar to that obtained when the entire vehicle is modeled and analyzed.

[0074] Furthermore, it offers the benefit of further improving the efficiency of developing forward crash analysis components for electric vehicle battery protection.

[0075] The following table compares the analysis of the entire vehicle model with the analysis method of the collision model according to the present invention. Table 1 shows the component-specific results for the full frontal collision test, Table 2 for the partial frontal collision test, and Table 3 for the small overlap collision test.

[0076] [Table 1]

[0077] [Table 2]

[0078] [Table 3]

[0079] The table above shows the results of tests conducted using the overall modeling method in each test, focusing mainly on energy-absorbing components, and the results obtained using one embodiment of the present invention. The results of the overall modeling method are labeled as "Overall Modeling," the results obtained using one embodiment of the present invention are labeled as "Simplified Modeling," and the comparison between the two values ​​is labeled as "Simple / Full." As shown above, it can be seen that in all tests, the energy absorption values ​​of the components that mainly absorb impact are within 10%, which is a reliable result.

[0080] Furthermore, according to one embodiment of the present invention, it can be seen that the required time is significantly reduced by approximately 35% in the case of a full frontal collision test in which the collision is analyzed using overall modeling, from 21h36m (100.0%) to 7h22m (34.1%), in the case of a partial frontal collision test, from 20h49m (100.0%) to 7h29m (35.9%), and in the case of a small overlap collision test, from 21h14m (100.0%) to 7h17m (34.3%).

[0081] Although the present invention has been described above, primarily in terms of examples, the present invention is not limited to the examples described above and can be modified and implemented by a person of ordinary skill without changing the technical idea of ​​the present invention as claimed in the claims. [Explanation of Symbols]

[0082] S10 First area setting stage S20 Second area setting stage S30 Correction stage S40 Battery frame setting stage S50 Analysis stage 1. Input section 2. Correction section 3 Storage section 4 Arithmetic section 5 Display section

Claims

1. In a method for analyzing vehicle collision models based on finite element analysis using software, The first input unit receives the definition of a first region, which is a region where deformation occurs due to collision, and receives modeling input for the first region, saving it to the storage unit in the first region setting step; The second input unit receives a definition of a second region, which is a region where deformation due to collision is relatively small; the second region is designated as a rigid body element; and the second region setting step receives simplified information for the rigid body element and stores it in the storage unit; Correction step in which the correction unit specifies a first beam element at the boundary between the first region and the second region, connects one end of the first beam element to the model, connects the other end to the rigid body element and saves it, and corrects the error caused by the simplification of the second region; and A collision model analysis method comprising: an analysis step in which a calculation unit automatically calculates the collision via a finite element analysis algorithm using the values ​​stored in the storage unit and the correction unit;

2. In the aforementioned correction step, A collision model analysis method according to claim 1, comprising: a correction input step in which a first cross section, which is a cross section in the width direction of the vehicle, is input to a vehicle part designated as the first beam element and located at the boundary; a correction calculation step in which a first moment of inertia, which is the moment of inertia of the first cross section, is automatically calculated; and a correction storage step in which one end of the first beam element is connected to the first cross section of the model and the first moment of inertia is stored as information of the first beam element.

3. The first cross-section is, A method for analyzing a collision model according to claim 2, wherein the cross-sections are those of the front pillar, rocker, and longitudinal floor.

4. Located between the second domain setting step and the calculation step, The collision model analysis method according to claim 3, further comprising a battery frame setting step in which the correction unit sets a second beam element for a battery frame surrounding the battery area of ​​the vehicle, connects one end of the second beam element to the model, and connects the other end to the rigid element and saves the model.

5. The aforementioned battery frame setting step is A battery frame input step involves inputting a second cross-section, which is the cross-section in the width direction of the side frame forming the side of the battery frame and the battery longitudinal frame arranged in the longitudinal direction of the vehicle below the battery area. A battery frame calculation step in which the second moment of inertia, which is the moment of inertia of the second cross-section, The collision model analysis method according to claim 4, comprising a battery frame saving step of saving the second cross section, the calculated value of the second moment of inertia, and the setting in which one end of the second beam element is connected to the second cross section.

6. The aforementioned battery frame setting stage includes: The battery front frame, which is arranged in the width direction of the vehicle and located in the first region, is input as a beam element and stored as a third beam element. The collision model analysis method according to claim 5, further comprising a front frame setting step of setting the third beam element at the position of the front frame and calculating and storing the third moment of inertia at an arbitrary cross section of the front frame in the vehicle length direction.

7. The simplified information is, A method for analyzing a collision model according to claim 1, including the center of gravity and mass of the second region.

8. The collision in the aforementioned collision model analysis is a frontal collision. The collision model analysis method according to claim 1, wherein the first region includes a part of the battery frame.

9. The first region is, The method for analyzing a collision model according to claim 8, comprising the front bumper, front subframe, and front side members of the vehicle.

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