Subsystem simulation method for simulating small offset collision of whole vehicle

Abstract

The invention belongs to the technical field of collision simulation, and particularly relates to a subsystem simulation method for simulating small-offset collision of a whole vehicle, which comprises the following steps of: arranging a collision three-way acceleration sensor at a preset position on the whole vehicle to be subjected to small-offset collision, and executing a small-offset collision experiment on the whole vehicle; acquiring acceleration-time curve data of the preset position in the X-axis direction, the Y-axis direction and the Z-axis direction of the sensor coordinate system; then, on the basis of the whole vehicle simulation model, a small offset collision subsystem model with a dummy is constructed, and rigid body processing is carried out on a corresponding sub-model at a preset position; and finally, applying the acceleration-time curve data in the three directions obtained in the step S1 to corresponding preset positions in the small offset collision subsystem model, and after the small offset collision subsystem model completes an experiment, outputting a collision test result of each part of the dummy. The problem that a subsystem simulation method in the prior art cannot meet simulation and analysis requirements of small offset collision can be solved.

Description

Technical Field

[0001] The invention belongs to the technical field of collision simulation, and in particular relates to a subsystem simulation method for simulating a small offset collision of a whole vehicle. Background Art

[0002] In the field of automotive engineering, the safety performance of automobile collision has always been a crucial research topic. As an effective means of quickly evaluating the safety performance of automobiles, automobile collision safety simulation plays an extremely critical role in the process of automobile research and development.

[0003] Although the traditional vehicle collision simulation method can comprehensively simulate the various mechanical responses and deformations of the vehicle during the collision, it has a significant drawback, that is, the calculation cycle is too long. At a time when the competition in automobile R&D is becoming increasingly fierce, the lengthy calculation cycle will undoubtedly greatly delay the development progress of the product and increase the R&D cost, which is an extremely unfavorable factor for the automobile industry that pursues high efficiency and speed.

[0004] In order to overcome the problem of long calculation cycle of whole vehicle collision simulation, some subsystem simulation schemes have emerged. For example, the slide subsystem models with unidirectional loading and the slide subsystem models with node information loading have indeed improved the simulation efficiency to a certain extent, and can better reproduce the conventional collision forms. However, with the continuous development of automobile technology, especially the rise of new intelligent driving technologies, the form of automobile accidents has changed significantly. In actual accident scenarios, the boundary conditions of collisions have become more complex and diverse. For example, in some special collision accidents, the vehicle body will have rotational motion during the collision process, and the existing subsystem simulation models are limited by their design principles, and it is difficult to accurately reproduce this collision process with rotational motion.

[0005] The emergence of new collision standards represented by small offset collisions has brought new challenges to automobile collision safety simulation. Due to the particularity of the collision position of small offset collisions, the force distribution, deformation mode and energy absorption method of the vehicle during the collision are quite different from those of traditional collision forms. When conducting simulation analysis, the number of working conditions that need to be expanded has increased significantly, and the existing subsystem simulation methods can no longer meet the needs of accurate simulation and analysis of small offset collisions. This urgently requires a new subsystem simulation method that can effectively improve the simulation efficiency while ensuring the simulation accuracy, and can accurately reproduce various complex collision situations including the rotation of the vehicle body, thereby promoting the overall improvement of the research and development efficiency of automobile collision safety performance, in order to adapt to the rapid development of the automotive industry and increasingly stringent safety standards. Summary of the invention

[0006] The technical problem solved by the present invention is to provide a subsystem simulation method for simulating a small offset collision of a whole vehicle, so as to solve the problem that the subsystem simulation method in the prior art cannot meet the simulation and analysis requirements of the small offset collision.

[0007] The basic solution provided by the present invention is a subsystem simulation method for simulating a small offset collision of a whole vehicle, comprising:

[0008] S1: Arrange a collision three-axis acceleration sensor at a preset position on the vehicle to be subjected to a small offset collision, and perform a small offset collision test on the vehicle to obtain acceleration-time curve data in the three directions of the sensor coordinate system, namely, the X-axis, the Y-axis, and the Z-axis, at the preset position;

[0009] S2: Based on the whole vehicle simulation model, a small offset collision subsystem model with a dummy is constructed, and the corresponding submodel at the preset position is rigidified;

[0010] S3: Apply the acceleration-time curve data in the three directions obtained in S1 to the corresponding preset positions in the small offset collision subsystem model. After the small offset collision subsystem model completes the experiment, output the collision test results of various parts of the dummy.

[0011] Further, the S1 includes:

[0012] S1-1: Select three positions on the vehicle that are horizontal and not deformed in the collision as preset positions, install collision three-axis acceleration sensors at the preset positions, and construct the sensor coordinate system;

[0013] S1-2: According to the requirements of the small offset collision test, the whole vehicle completes the small offset collision test and outputs the speed-time curve data of three positions in the sensor coordinate system;

[0014] S1-3: Filtering and performing a preset derivative calculation on the velocity-time curve data to obtain acceleration-time curve data at three positions in the X-axis, Y-axis and Z-axis directions of the sensor coordinate system.

[0015] Further, in S1-3, the speed-time curve data is filtered and the preset derivative calculation is performed as follows:

[0016] Set the absolute coordinate system to the XOY coordinate system, then the sensor coordinate system is X′OY′; where X′OY′ is the angle θ rotated around the Z axis;

[0017] Based on the displayed Euler formula, the translation of the vehicle along the X-axis, Y-axis and Z-axis and the rotation along the Z-axis are calculated as follows:

[0018] y n+1 =y n +hf(xn ,y n )

[0019] Among them, h represents the solution step size, f(x n ,y n ) represents a step-length rotation angle solving function; according to the above formula, we can deduce that y1=y0+hf(x0,y0), y2=y1+hf(x1,y1), …, y n+1 =y n +hf(x n ,y n ), calculate θ at time t n The value of is expressed as:

[0020] θ n+1 =θ n +hf(t n ,θ n )

[0021] Among them, f(t n ,θ n ) represents a step-size corner solving function:

[0022]

[0023] in, Respectively represent the X-axis, Y-axis and Z-axis t on the sensor coordinate system n The acceleration of the moment;

[0024] Decomposing the acceleration in three directions in the sensor coordinate system, we can get the acceleration in the absolute coordinate system. The expression is:

[0025]

[0026] in, Indicates the X-axis, Y-axis and Z-axis in the absolute coordinate system n The acceleration of the moment;

[0027] The acceleration-time curve data is obtained based on the acceleration and time of the X-axis, Y-axis and Z-axis in the absolute coordinate system.

[0028] Furthermore, in S1-1, the three positions on the vehicle that are horizontal and have not been deformed in the collision are the lower left B-pillar of the vehicle, the lower right B-pillar of the vehicle, and the right A-pillar.

[0029] Further, the S2 includes:

[0030] S2-1: Select the floor, B-pillar, seat, front windshield, instrument panel, center channel, dummy and restraint system models to build the subsystem model;

[0031] S2-2: In the subsystem model, the lower left part of the vehicle's B-pillar is rigidified together with the left side door sill, left side floor and left seat crossbeam; the lower right part of the vehicle's B-pillar, the right side door sill, right side floor and right seat crossbeam are rigidified; the right A-pillar is rigidified together with the right A-pillar, right front floor and passenger compartment instrument panel.

[0032] An electronic device includes a processor and a memory, wherein the memory stores programs or instructions, and the processor executes the above-mentioned subsystem simulation method for simulating a small offset collision of a whole vehicle by calling the program or instructions stored in the memory.

[0033] A computer-readable storage medium stores a program or instruction, wherein the program or instruction enables a computer to execute a subsystem simulation method for simulating a small offset collision of a whole vehicle as described above.

[0034] The principle and advantage of the present invention are: in order to achieve a more efficient small offset collision subsystem simulation, in this scheme, firstly, a position on the whole vehicle that is horizontal and does not produce deformation in the collision is selected to install a collision three-axis acceleration sensor, wherein the selected positions are three, namely, the lower left of the B-pillar, the lower right of the B-pillar and the right A-pillar, and the acceleration-time curve data is calculated and obtained from the three selected positions, and then according to the principle that the sensor coordinate system has a deflection angle relative to the absolute coordinate system, the coordinate system is calculated and transformed, so that the acceleration measured at each moment in the sensor coordinate system is converted into the acceleration of the absolute coordinate system, and then according to the acceleration-time curve data on the converted absolute coordinate system, the boundary conditions are applied to the subsystem model constructed by the whole vehicle simulation model. During the application process, the vehicle model structure involved in the above three positions is rigidified, so that when the converted acceleration is applied to the subsystem model, the output results of each part of the dummy under the acceleration-time curve are output, and a highly efficient small offset collision experiment is achieved.

[0035] Therefore, the advantages of the present invention are that the positions for arranging the three acceleration sensors are simple to select, the boundary application method is simple, the work efficiency is high, and the expenses and material losses of the collision experiment are reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a flowchart of an embodiment of the present invention;

[0037] Figure 2 A schematic diagram of a sensor coordinate system and an absolute coordinate system according to an embodiment of the present invention;

[0038] Figure 3 A schematic diagram of selecting a preset position in an embodiment of the present invention;

[0039] Figure 4 This is a schematic diagram of a small offset collision experiment in an embodiment of the present invention;

[0040] Figure 5 Schematic diagram of the structure of an electronic device in an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The following is further described in detail through specific implementation methods:

[0042] The symbols in the drawings of the specification include: electronic device 400 , processor 401 , memory 402 , input device 403 , and output device 404 .

[0043] In the traditional automobile collision subsystem simulation method, there are two common ways to perform boundary application. One is to apply the sliding table of the whole vehicle collision acceleration-time history in one direction, and the other is to apply the node displacement-time history information of the corresponding node of the whole vehicle to each node of the subsystem simulation model. In this scheme, based on the subsystem model, the acceleration-time curves in three absolute coordinate directions are applied at three position levels of the car and at specific positions where no deformation occurs in the collision. Specifically:

[0044] The embodiment is basically as shown in the attached Figure 1 As shown: A subsystem simulation method for simulating a small offset collision of a whole vehicle, comprising:

[0045] S1: Arrange a collision three-axis acceleration sensor at a preset position on the vehicle to be subjected to a small offset collision, and perform a small offset collision test on the vehicle to obtain acceleration-time curve data in the three directions of the sensor coordinate system X-axis, Y-axis and Z-axis at the preset position; wherein S1 includes:

[0046] S1-1: Select three positions on the vehicle that are horizontal and not deformed in the collision as preset positions, install collision three-axis acceleration sensors at the preset positions, and construct the sensor coordinate system;

[0047] S1-2: According to the requirements of the small offset collision test, the whole vehicle completes the small offset collision test and outputs the speed-time curve data of three positions in the sensor coordinate system;

[0048] S1-3: Filtering and performing a preset derivative calculation on the velocity-time curve data to obtain acceleration-time curve data at three positions in the X-axis, Y-axis and Z-axis directions of the sensor coordinate system.

[0049] In this embodiment, if Figure 3As shown, the three positions on the vehicle that are horizontal and have not been deformed in the collision are specifically the lower left of the vehicle's B-pillar, the lower right of the vehicle's B-pillar and the right A-pillar, and collision three-axis acceleration sensors are arranged at these three positions. Therefore, under the premise that the three positions of the vehicle's lower left B-pillar, the vehicle's lower right B-pillar and the right A-pillar have special collision performances of being horizontal and not being deformed in the collision, the acceleration information of these three positions can be obtained through the collision three-axis acceleration sensor.

[0050] After the collision three-axis acceleration sensor is installed, a small offset collision is performed according to the small offset collision experiment. In this embodiment, the small offset collision adopts a 25% small offset collision, such as Figure 4 As shown in the figure, after the collision experiment is completed, the velocity-time curve data at three positions are output. In this scheme, the coordinate system in three directions with the collision three-axis acceleration sensor as the origin is the sensor coordinate system. The sensor coordinate system is obtained by rotating on the basis of the absolute coordinate system, that is, the absolute coordinate system at t = 0. Therefore, Figure 2 As shown, the coordinate system XOY is an absolute coordinate system, and the coordinate system X′OY′ is a sensor coordinate system, wherein the coordinate system X′OY′ is obtained by rotating the Z axis of the coordinate system XOY by an angle of θ.

[0051] Therefore, after the above 25% small offset collision test is completed, the output speed-time curve data is filtered and derived. Specifically, the filtering process uses SAE60 filtering. The speed-time curve data after filtering needs to be derived and then converted into acceleration in the absolute coordinate system, specifically:

[0052] Based on the displayed Euler formula, the translation of the vehicle along the X-axis, Y-axis and Z-axis and the rotation along the Z-axis are calculated as follows:

[0053] y n+1 =y n +hf(x n ,y n )

[0054] Wherein, h represents the solution step length. Too large a step length will affect the stability of the Euler formula. Therefore, the solution step is h=0.001s in this embodiment. n ,y n ) represents a step-length rotation angle solving function. The initial value y0 is known, that is, the rotation angle θ is known. According to the above formula, we can deduce that y1=y0+hf(x0,y0), y2=y1+hf(x1,y1), …, y n+1 =y n +hf(x n ,y n ), calculate θ at time t n The value of is expressed as:

[0055] θ n+1 =θ n +hf(t n ,θ n )

[0056] Among them, f(t n ,θ n ) represents a step-size corner solving function:

[0057]

[0058] in, Respectively represent the X-axis, Y-axis and Z-axis t on the sensor coordinate system n The acceleration of the moment;

[0059] Since the acceleration on the vehicle body is the value measured by the sensor at a certain moment, it is the acceleration along the sensor coordinate system at that moment, rather than the acceleration of the absolute coordinate system. Therefore, the coordinate system needs to be converted, that is, the acceleration measured by the sensor coordinate system at each moment is converted into the acceleration of the absolute coordinate system.

[0060] Since the three collision triaxial acceleration sensors are all horizontally positioned during the collision and no deformation occurs during the collision, in order to avoid interference of degrees of freedom, the rotation angle θ of the sensor coordinate system at the lower right of the B-pillar relative to the absolute coordinate system is selected as the rotation angle of the three sensor coordinate systems relative to the absolute coordinate system in this scheme.

[0061] Therefore, the acceleration in the three directions of the sensor coordinate system is decomposed to obtain the acceleration in the absolute coordinate system, and the expression is:

[0062]

[0063] in, Indicates the X-axis, Y-axis and Z-axis in the absolute coordinate system n The acceleration at the moment; wherein, the coordinate system is set to undergo only rotational motion around the Z axis, so the acceleration on the Z axis remains unchanged.

[0064] The acceleration-time curve data is obtained based on the acceleration and time of the X-axis, Y-axis and Z-axis in the absolute coordinate system.

[0065] Therefore, the acceleration-time curve data in the absolute coordinate system can be obtained through the above step S1, and then the subsystem model is constructed, specifically:

[0066] S2: Based on the whole vehicle simulation model, a small offset collision subsystem model with a dummy is constructed, and the corresponding submodel at the preset position is rigidified; S2 includes:

[0067] S2-1: Select the floor, B-pillar, seat, front windshield, instrument panel, center channel, dummy and restraint system models to build the subsystem model;

[0068] S2-2: In the subsystem model, the lower left part of the vehicle's B-pillar is rigidified together with the left side door sill, left side floor and left seat crossbeam; the lower right part of the vehicle's B-pillar, the right side door sill, right side floor and right seat crossbeam are rigidified; the right A-pillar is rigidified together with the right A-pillar, right front floor and passenger compartment instrument panel.

[0069] S3: Apply the acceleration-time curve data in the three directions obtained in S1 to the corresponding preset positions in the small offset collision subsystem model. After the small offset collision subsystem model completes the experiment, output the collision test results of various parts of the dummy.

[0070] Therefore, in the present application, on the basis of the subsystem model, acceleration-time curve data in the three directions of X, Y, and Z of the absolute coordinate system taken from the corresponding position points of the whole vehicle collision test are added at three positions: the lower left of the B-pillar, the lower right of the vehicle B-pillar, and the right A-pillar. When collecting data, the three selected positions are horizontal and the vehicle body structure where the collision three-axis acceleration sensor is located will not be deformed, which greatly ensures the accuracy and completeness of the collected acceleration data. At the same time, when performing boundary loading, according to the acceleration-time curve data converted in this scheme, a general acceleration application method can be adopted, and then the output results of various parts of the dummy under the acceleration-time curve data are obtained, which greatly improves the efficiency of small offset collision experiments.

[0071] like Figure 5 As shown, in another embodiment of the present embodiment, an electronic device is also included, and the electronic device 400 includes one or more processors 401 and a memory 402.

[0072] The processor 401 may be a central processing unit (CPU) or other forms of processing units having data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device 400 to perform desired functions.

[0073] The memory 402 may include one or more computer program products, and the computer program product may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may include, for example, random access memory (RAM) and / or cache memory (cache), etc. The non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 401 may run the program instructions to implement a subsystem simulation method for simulating a small offset collision of a whole vehicle and / or other desired functions of any embodiment of the present invention described above. Various contents such as initial external parameters, thresholds, etc. may also be stored in the computer-readable storage medium.

[0074] In one example, the electronic device 400 may further include: an input device 403 and an output device 404, which are interconnected via a bus system and / or other forms of connection mechanisms (not shown). The input device 403 may include, for example, a keyboard, a mouse, etc. The output device 404 may output various information to the outside, including early warning information, braking force, etc. The output device 404 may include, for example, a display, a speaker, a printer, a communication network and a remote output device connected thereto, etc.

[0075] Of course, to simplify, Figure 5 Only some of the components related to the present invention in the electronic device 400 are shown, and components such as a bus, an input / output interface, etc. are omitted. In addition, according to specific application conditions, the electronic device 400 may also include any other appropriate components.

[0076] In addition to the above-mentioned methods and devices, an embodiment of the present invention may also be a computer program product, which includes computer program instructions, which, when executed by a processor, enable the processor to execute the steps of a subsystem simulation method for simulating a small offset collision of a whole vehicle provided in any embodiment of the present invention.

[0077] The computer program product may be written in any combination of one or more programming languages ​​to write program code for performing the operations of the embodiments of the present invention, including object-oriented programming languages ​​such as Java, C++, etc., and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user computing device, partially on the user device, as a separate software package, partially on the user computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0078] In addition, an embodiment of the present invention may also be a computer-readable storage medium on which computer program instructions are stored. When the computer program instructions are executed by a processor, the processor executes the steps of a subsystem simulation method for simulating a small offset collision of a whole vehicle provided in any embodiment of the present invention.

[0079] The computer readable storage medium can adopt any combination of one or more readable media. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium can include, for example, but is not limited to, a system, device or device of electricity, magnetism, light, electromagnetic, infrared, or semiconductor, or any combination of the above. More specific examples (non-exhaustive list) of readable storage media include: an electrical connection with one or more wires, a portable disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0080] The above are only embodiments of the present invention. Common knowledge such as the known specific structures and characteristics in the scheme is not described in detail here. Ordinary technicians in the relevant field know all the common technical knowledge in the technical field to which the invention belongs before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply conventional experimental means before that date. Ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A subsystem simulation method for simulating a small offset collision of a whole vehicle, characterized in that: include: S1: Arrange a collision three-axis acceleration sensor at a preset position on the vehicle to be subjected to a small offset collision, and perform a small offset collision test on the vehicle to obtain acceleration-time curve data in three directions of the sensor coordinate system, namely, the X-axis, the Y-axis, and the Z-axis, at the preset position; S2: Based on the whole vehicle simulation model, a small offset collision subsystem model with a dummy is constructed, and the corresponding submodel at the preset position is rigidified; S3: Apply the acceleration-time curve data in the three directions obtained in S1 to the corresponding preset positions in the small offset collision subsystem model. After the small offset collision subsystem model completes the experiment, output the collision test results of each part of the dummy.

2. The subsystem simulation method for simulating a small offset collision of a whole vehicle according to claim 1, characterized in that: The S1 includes: S1-1: Select three positions on the vehicle that are horizontal and not deformed in the collision as preset positions, install collision three-axis acceleration sensors at the preset positions, and construct the sensor coordinate system; S1-2: According to the requirements of the small offset collision test, the whole vehicle completes the small offset collision test and outputs the speed-time curve data of three positions in the sensor coordinate system; S1-3: Filtering and performing a preset derivative calculation on the velocity-time curve data to obtain acceleration-time curve data at three positions in the X-axis, Y-axis and Z-axis directions of the sensor coordinate system.

3. The subsystem simulation method for simulating a small offset collision of a whole vehicle according to claim 2, characterized in that: In S1-3, the filtering process and the preset derivative calculation process of the speed-time curve data are specifically as follows: Set the absolute coordinate system to the XOY coordinate system, then the sensor coordinate system is X′OY′; where X′OY′ is the angle θ rotated around the Z axis; Based on the displayed Euler formula, the translation of the vehicle along the X-axis, Y-axis and Z-axis and the rotation along the Z-axis are calculated as follows: and n+1 =and n +hf(x n ,and n ) Among them, h represents the solution step size, f(x n ,y n ) represents a step-length rotation angle solving function; according to the above formula, we can deduce that y1=y0+hf(x0,y0), y2=y1+hf(x1,y1), …, y n+1 =y n +hf(x n ,y n ), calculate θ at time t n The value of is expressed as: i n+1 =θ n +hf(t n ,i n ) Among them, f(t n ,θ n ) represents a step-size corner solving function: in, Respectively represent the X-axis, Y-axis and Z-axis t on the sensor coordinate system n The acceleration of the moment; Decomposing the acceleration in three directions in the sensor coordinate system, we can get the acceleration in the absolute coordinate system. The expression is: in, Represents the X-axis, Y-axis and Z-axis in the absolute coordinate system n The acceleration of the moment; The acceleration-time curve data is obtained based on the acceleration and time of the X-axis, Y-axis and Z-axis in the absolute coordinate system.

4. The subsystem simulation method for simulating a small offset collision of a whole vehicle according to claim 3, characterized in that: In the S1-1, the three positions on the vehicle that are horizontal and have not been deformed in the collision are the lower left B-pillar, the lower right B-pillar and the right A-pillar.

5. The subsystem simulation method for simulating a small offset collision of a whole vehicle according to claim 4, characterized in that: The S2 includes: S2-1: Select the floor, B-pillar, seat, front windshield, instrument panel, center channel, dummy and restraint system models to build the subsystem model; S2-2: In the subsystem model, the lower left part of the vehicle's B-pillar is rigidified together with the left side door sill, left side floor and left seat crossbeam; the lower right part of the vehicle's B-pillar, the right side door sill, right side floor and right seat crossbeam are rigidified; the right A-pillar is rigidified together with the right A-pillar, right front floor and passenger compartment instrument panel.

6. An electronic device, characterized in that: It comprises a processor and a memory, wherein the memory stores programs or instructions, and the processor executes a subsystem simulation method for simulating a small offset collision of a whole vehicle as described in any one of claims 1 to 5 by calling the programs or instructions stored in the memory.

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a program or instruction, and the program or instruction enables a computer to execute a subsystem simulation method for simulating a small offset collision of a whole vehicle as described in any one of claims 1 to 5 above.

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