Simulation analysis method for vibration performance of rear-row entertainment display screen

Abstract

The invention belongs to the technical field of automobile part vibration performance analysis, and particularly relates to a rear-row entertainment display screen vibration performance simulation analysis method. Establishing a vehicle body model, a seat model and a rear-row entertainment display screen model through a finite element method, establishing a finite element model based on the models, and carrying out modal and vibration transfer function performance analysis from a vehicle body key attachment point to a rear-row entertainment display screen; whether the vibration performance reaches the standard or not is judged by comparing the modal and vibration transfer function key result value with a target value; the risk is judged according to the simulation result, the rear-row entertainment display screen and other connection structures related to the rear-row entertainment display screen are optimized in the data stage, and the cost for solving later problems of a project and the cycle cost are reduced; and meanwhile, the simulation analysis period is shortened, and the iterative optimization efficiency of the scheme is greatly improved.

Description

Technical Field

[0001] The invention belongs to the technical field of vibration performance analysis of automobile accessories, and in particular relates to a vibration performance simulation analysis method for a rear entertainment display screen. Background Art

[0002] As users' demand for smart cockpits continues to increase, many models on the market are currently equipped with rear entertainment screens. Usually, the rear entertainment screen is installed on the backrest of the front seat, which is prone to vibration under the stimulation of excitation sources such as the road surface and the engine. If the rear entertainment screen produces obvious vibrations during the driving process of the vehicle, it will affect the user experience of the rear passengers, and in severe cases, it may cause dizziness to the passengers. If you want to improve the user experience of the rear passengers on the rear entertainment screen, you need to control the vibration performance of the rear entertainment screen during the development stage. At present, the industry's research on the vibration performance of the display is mainly concentrated on the front center control display, and more emphasis is placed on the research of the display connection device, rather than the research on its vibration performance mechanism and simulation analysis methods.

[0003] During vehicle development, if the vibration performance of the rear entertainment display screen is not fully considered in the early structural design, there is a high possibility that vehicle verification problems will occur due to poor vibration performance of the rear entertainment display screen in the middle and late stages of project development, that is, from the confirmation of prototype tooling samples to the trial production stage. If the problem is analyzed and solved at this stage, it will affect the normal development progress of the project, or incur design change costs. If this problem is not solved, users will complain after the project is mass-produced, affecting the quality and reputation of the vehicle model.

[0004] In summary, it is of great significance to use simulation methods to analyze the vibration performance of the rear entertainment display screen in the early stage of project development to avoid risks in advance. Summary of the invention

[0005] In order to overcome the above problems, the present invention provides a method for simulating and analyzing the vibration performance of a rear entertainment display screen; judge the risks based on the simulation results, optimize the rear entertainment display screen and other related connection structures in the data stage, and reduce the cost and cycle cost of solving problems in the later stage of the project; at the same time, the simulation analysis cycle is shortened and the efficiency of iterative optimization of the solution is greatly improved.

[0006] A vibration performance simulation analysis method for a rear entertainment display screen includes the following contents:

[0007] Step 1: Model preparation

[0008] Step 1.1, import the finite element solid models of the vehicle body, seats, and rear entertainment display screen into the pre-processing software, and complete the establishment of the finite element models of the vehicle body, seats, and rear entertainment display screen through the finite element meshing function integrated in the pre-processing software;

[0009] Step 1.2, establishing the connection relationship between the seat, rear entertainment display screen and the vehicle body in the pre-processing software;

[0010] Step 1.3, output all component files of the finite element model in bdf format through the pre-processing software, import the output file into the virtual simulation navigation system, assign thickness, elastic modulus, density, and Poisson's ratio attributes to the body shell unit, assign elastic modulus, density, and Poisson's ratio attributes to the seat and rear entertainment display tetrahedron unit, and finally select the system integrated 0-100Hz solution card to create a solution load step to form a solution model;

[0011] Step 2: Calculate and solve

[0012] Click on the modal and vibration transfer function in the simulation generator to calculate the modal and vibration transfer function of the solution model in step 1.3. If the solution is successful, the result files in op2 and pch formats will be generated.

[0013] Step 3: Modal result extraction

[0014] Use the Python automated modal op2 result post-processing script integrated in the virtual simulation navigation system to extract the modal key result values, modal key result images and modal key result gif animations in the result files;

[0015] Step 4, using the Python automated vibration transfer function pch result post-processing script integrated in the virtual simulation navigation system to extract the vibration transfer function key result curve, vibration transfer function key result value and vibration transfer function key picture in the result file;

[0016] Step 5: Result judgment

[0017] By comprehensively comparing the modal and vibration transfer function key result values ​​with the target values, it is determined whether the vibration performance of the rear entertainment display meets the requirements. If the modal key result value is greater than or equal to the modal target value, and the vibration transfer function key result value is less than or equal to the vibration transfer function target value, the vibration performance meets the standard; otherwise, the vibration performance does not meet the standard, and the structure of the rear entertainment display needs to be optimized and the analysis process should be restarted until the vibration performance meets the standard.

[0018] The pre-processing software in step 1.1 and step 1.2 is HyperMesh software.

[0019] The connection relationship between the seats, rear entertainment screens and the vehicle body in step 1.2 refers to the positions of the connection points between the seats, rear entertainment screens and the vehicle body and the sizes of the bolts used for fixing the connection at the connection points.

[0020] The process of outputting all component files of the finite element model in bdf format through the pre-processing software in step 1.3 is as follows: click the model output function key in the HyperMesh software, select the file type Nastran, then click to output all components of the finite element model, select the format as bdf format, and obtain all component files of the finite element model.

[0021] In the step five, the structure of the rear entertainment screen is optimized, that is, the connection relationship between the body and the seat, and the seat and the rear entertainment screen in the finite element model described in step 1.2 is modified, that is, the position of the connection points between the seat, the rear entertainment screen and the body and the size of the bolts used for fixing the connection at the connection points are modified.

[0022] In the step 5, restarting the analysis process means repeating steps 1.3 to step 5 after optimizing the structure of the rear entertainment display screen.

[0023] The modal target value and vibration transfer function target value in step five are obtained based on the vibration performance database of the benchmark vehicle's rear entertainment display or the design task book requirements, and a Python script file of the rear entertainment display modal and vibration transfer function target value is created before performing step two. The script files are uploaded to the modal target value module and vibration transfer function target value module of the virtual simulation navigation system, respectively, for result judgment in step five.

[0024] Beneficial effects of the present invention:

[0025] The present invention has the advantages of fast speed and high quality through the establishment of finite element models, combined with material properties and automatic assembly of load step files, which can greatly improve the efficiency of iterative analysis of solutions, promote the realization of efficient project development, and meet the current demand for faster project development cycles.

[0026] The present invention is more efficient and accurate than manual identification in extracting key results through modal and vibration transfer function, and the display of modal vibration shape and vibration transfer function key result curves is more intuitive. Generating reports can reduce the process of manually intercepting key result images, manually entering key result values, and manually entering basic information such as project number and report writing date. The entire analysis process has a high degree of automation and fast iteration speed, which helps to avoid actual vehicle verification problems caused by poor vibration performance of the rear entertainment display screen in the early stage of development, thereby further avoiding project development delays, design change costs, and user complaints caused by problems.

[0027] The present invention adopts simulation to analyze the vibration performance of the rear entertainment display screen, and uses simulation means to realize risk prediction in the early stage of project development, so as to identify the risks in the data stage in advance; it realizes the model material property assignment, load step creation and post-processing automation, which can greatly improve the efficiency of solution iteration and shorten the solution optimization cycle. DETAILED DESCRIPTION

[0028] The present invention will be further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention.

[0029] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0031] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are only for the convenience of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0032] Example 1

[0033] A vibration performance simulation analysis method for a rear entertainment display screen includes the following contents:

[0034] Step 1: Model preparation

[0035] Step 1.1, import the finite element solid model of the vehicle body, seats, and rear entertainment display screen into the pre-processing software HyperMesh, and complete the establishment of the finite element model of the vehicle body, seats, and rear entertainment display screen through the finite element meshing function integrated in the pre-processing software HyperMesh;

[0036] Step 1.2, establish the connection between the seat, rear entertainment display screen and the vehicle body in the pre-processing software HyperMesh;

[0037] Step 1.3, output all component files of the finite element model in bdf format through the pre-processing software, import the output file into the virtual simulation navigation system, use the system integrated Python automatic attribute script to assign the body shell unit thickness, elastic modulus, density, Poisson's ratio attributes, assign the seat and rear entertainment display tetrahedron unit elastic modulus, density, Poisson's ratio attributes, and finally select the system integrated 0-100Hz solution card to create a solution load step to form a solution model;

[0038] Step 2: Calculate and solve

[0039] According to the vibration performance database of the rear entertainment display screen of the benchmark vehicle or the requirements of the design task book, create a Python script file of the modal and vibration transfer function target value of the rear entertainment display screen, upload the script file to the modal and vibration transfer function target value module of the virtual simulation navigation system, click the modal and vibration transfer function solution in the simulation generator, and start the modal and vibration transfer function calculation of the solution model in step 1.3. If the solution is successful, the result files in op2 and pch formats will be automatically generated;

[0040] Step 3: Modal result extraction

[0041] According to the result file, the program uses the Python automated modal op2 result post-processing script integrated in the virtual simulation navigation system to automatically extract the modal key result values, modal key result images and modal key result gif animations in the result file;

[0042] Step 4, vibration transfer function result extraction: the program uses the Python automated vibration transfer function pch result post-processing script integrated in the virtual simulation navigation system according to the result file to automatically extract the vibration transfer function key result curve, vibration transfer function key result value and vibration transfer function key picture in the result file;

[0043] Step 5: Result judgment and report generation

[0044] By comprehensively comparing the key result values ​​of the modal and vibration transfer function with the target values, it is determined whether the vibration performance of the rear entertainment display meets the requirements. If the key result value of the modal is greater than or equal to the modal target value, and the key result value of the vibration transfer function is less than or equal to the target value of the vibration transfer function, the vibration performance meets the standard and a simulation analysis report is automatically generated; otherwise, the vibration performance does not meet the standard, and the structure of the rear entertainment display needs to be optimized and the analysis process should be restarted until the vibration performance meets the standard.

[0045] The pre-processing software in step 1.1 and step 1.2 is HyperMesh software.

[0046] The connection relationship between the seats, rear entertainment screens and the vehicle body in step 1.2 refers to the positions of the connection points between the seats, rear entertainment screens and the vehicle body and the sizes of the bolts used for fixing the connection at the connection points.

[0047] The process of step 1.3, outputting all component files of the finite element model in bdf format through the pre-processing software is as follows: click the model output function key in the HyperMesh software, select the file type Nastran, then click to output all components of the finite element model, select the format as bdf format, and obtain all component files of the finite element model.

[0048] In the step five, the structure of the rear entertainment display screen is optimized, that is, the connection relationship between the vehicle body and the seat, and the seat and the rear entertainment display screen in the finite element model in step 1.2 is modified.

[0049] In the step 5, restarting the analysis process means repeating steps 1.3 to step 5 after optimizing the structure of the rear entertainment display screen.

[0050] The modal target value and vibration transfer function target value in step five are obtained based on the vibration performance database of the benchmark vehicle's rear entertainment display or the design task book requirements, and a Python script file of the rear entertainment display modal and vibration transfer function target value is created before performing step two. The script files are uploaded to the modal target value module and vibration transfer function target value module of the virtual simulation navigation system, respectively, for result judgment in step five.

[0051] The present invention adopts a simulation analysis method to solve the vibration performance problem in three aspects: first, in the early stage of the project, the vehicle body model, seat model, rear entertainment display screen and other accessory models are established by the finite element method, and the seat-rear entertainment display screen assembly vehicle body assembly modal performance analysis is carried out; second, based on the above assembly model, the vibration transfer function performance analysis of the key attachment points of the vehicle body to the rear entertainment display screen is carried out; third, this method also provides an efficient automated analysis method, and the maximum degree of automation is reflected in four steps. First, automation is realized at the model loading level, and automated scripts are used for the vehicle body, seats, rear entertainment display screen, other accessories and load step loading files for solving. This implementation, secondly, for the post-processing of modal results, including the extraction of key result values ​​of modal frequencies, the identification of key result images, and the display of key result gif animations, greatly improves the efficiency of simulation calculation and analysis work; thirdly, for the post-processing of vibration transfer functions, including the extraction of key result curves, the extraction of key result values, the identification of key images, and the centralized comparison of the above-mentioned results, greatly improves the efficiency and visualization of vibration transfer function analysis work; fourthly, for the generation of simulation analysis reports, by extracting key result values ​​and images of modal and vibration transfer functions, a simulation analysis report based on a standardized template is automatically generated.

[0052] Example 2

[0053] Model preparation: The finite element solid models of the vehicle body, seats, rear entertainment display screen and other accessories need to be imported into the pre-processing software. The finite element model is established through the finite element mesh automatic division function integrated in the pre-processing software, and then the connection relationship between the seat-rear entertainment display screen assembly and the vehicle body is established. Next, the finite element model is exported to a bdf format file and imported into the automated model assembly program to automatically assign material properties to the components and create a solution load step.

[0054] Calculation and solution: According to the vibration performance database of the benchmark vehicle's rear entertainment display or the requirements of the design task book, set the target value file, and start calculating and solving the modal and vibration transfer function of the finite element model. After solving, generate op2 and pch format files.

[0055] Modal result extraction: The program automatically extracts modal key result values, key result images and key result gif animations based on the result files.

[0056] Vibration transfer function result extraction: The program automatically extracts key result curves, key result values ​​and key images based on the result files.

[0057] Result judgment and report generation: By comprehensively comparing the key result values ​​of the modal and vibration transfer function with the target values, it is judged whether the vibration performance of the rear entertainment display meets the requirements. If the modal calculation result is greater than or equal to the target value and the vibration transfer function curve meets expectations, the vibration performance meets the standard and a simulation analysis report is automatically generated; otherwise, the vibration performance does not meet the standard, and the structure needs to be optimized, the finite element model needs to be modified, and the analysis process needs to be restarted until the vibration performance meets the standard.

[0058] The preferred embodiments of the present invention are described in detail above. However, the protection scope of the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention. These simple variations all belong to the protection scope of the present invention.

[0059] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0060] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A vibration performance simulation analysis method for a rear entertainment display screen, characterized in that: It includes the following: Step 1: Model preparation Step 1.1, import the finite element solid models of the vehicle body, seats, and rear entertainment display screen into the pre-processing software, and complete the establishment of the finite element models of the vehicle body, seats, and rear entertainment display screen through the finite element meshing function integrated in the pre-processing software; Step 1.2, establishing the connection relationship between the seat, rear entertainment display screen and the vehicle body in the pre-processing software; Step 1.3, output all component files of the finite element model in bdf format through the pre-processing software, import the output file into the virtual simulation navigation system, assign thickness, elastic modulus, density, and Poisson's ratio attributes to the body shell unit, assign elastic modulus, density, and Poisson's ratio attributes to the seat and rear entertainment display tetrahedron unit, and finally select the system integrated 0-100Hz solution card to create a solution load step to form a solution model; Step 2: Calculate and solve Click on the modal and vibration transfer function in the simulation generator to calculate the modal and vibration transfer function of the solution model in step 1.

3. If the solution is successful, the result files in op2 and pch formats will be generated. Step 3: Modal result extraction Use the Python automated modal op2 result post-processing script integrated in the virtual simulation navigation system to extract the modal key result values, modal key result images and modal key result gif animations in the result files; Step 4, using the Python automated vibration transfer function pch result post-processing script integrated in the virtual simulation navigation system to extract the vibration transfer function key result curve, vibration transfer function key result value and vibration transfer function key picture in the result file; Step 5: Result judgment By comprehensively comparing the modal and vibration transfer function key result values ​​with the target values, it is determined whether the vibration performance of the rear entertainment display meets the requirements. If the modal key result value is greater than or equal to the modal target value, and the vibration transfer function key result value is less than or equal to the vibration transfer function target value, the vibration performance meets the standard; otherwise, the vibration performance does not meet the standard, and the structure of the rear entertainment display needs to be optimized and the analysis process should be restarted until the vibration performance meets the standard.

2. The vibration performance simulation analysis method of a rear entertainment display screen according to claim 1 is characterized in that: The pre-processing software in step 1.1 and step 1.2 is HyperMesh software.

3. The vibration performance simulation analysis method of a rear entertainment display screen according to claim 1 is characterized in that: The connection relationship between the seats, rear entertainment screens and the vehicle body in step 1.2 refers to the positions of the connection points between the seats, rear entertainment screens and the vehicle body and the sizes of the bolts used for fixing the connection at the connection points.

4. The vibration performance simulation analysis method of a rear entertainment display screen according to claim 2 is characterized in that: The process of outputting all component files of the finite element model in bdf format through the pre-processing software in step 1.3 is as follows: click the model output function key in the HyperMesh software, select the file type Nastran, then click to output all components of the finite element model, select the format as bdf format, and obtain all component files of the finite element model.

5. The vibration performance simulation analysis method of a rear entertainment display screen according to claim 1, characterized in that: In the step five, the structure of the rear entertainment screen is optimized, that is, the connection relationship between the body and the seat, and the seat and the rear entertainment screen in the finite element model described in step 1.2 is modified, that is, the position of the connection points between the seat, the rear entertainment screen and the body and the size of the bolts used for fixing the connection at the connection points are modified.

6. The vibration performance simulation analysis method of a rear entertainment display screen according to claim 1, characterized in that: In the step 5, restarting the analysis process means repeating steps 1.3 to step 5 after optimizing the structure of the rear entertainment display screen.

7. The vibration performance simulation analysis method of a rear entertainment display screen according to claim 1, characterized in that: The modal target value and vibration transfer function target value in step five are obtained based on the vibration performance database of the benchmark vehicle's rear entertainment display or the design task book requirements, and a Python script file of the rear entertainment display modal and vibration transfer function target value is created before performing step two. The script files are uploaded to the modal target value module and vibration transfer function target value module of the virtual simulation navigation system, respectively, for result judgment in step five.