A parametric test design platform and method for air suspension system based on modeFRONTIER co-simulation

Abstract

The invention discloses a block diagram of a parametric test design platform and method embodiment of an air suspension system based on modeFRONTIER joint simulation, comprising: a whole vehicle multi-body dynamics simulation module based on ADAMS / Car, a MATLAB parameter definition and data processing module, and a modeFRONTIER joint simulation platform. The MATLAB module is connected to modeFRONTIER through an interface, and the whole vehicle multi-body dynamics simulation module based on ADAMS / Car is called by using a simulation command file inside modeFRONTIER. The parameterization and modification of the air spring suspension system parameters are completed in the modeFRONTIER platform. Once the joint simulation starts, no human intervention is required in the entire joint simulation process, and the test design can be automatically performed, and the result of the test design can be output, which greatly saves development time and development cost; at the same time, by parameterizing the characteristic curve of the air spring, the ideal air spring characteristic curve of the vehicle equipped with the air spring suspension under the condition of good smoothness can be obtained, which provides a reference for the later air spring design of our company.

Description

Technical field:

[0001] The invention belongs to the technical field of automobile system dynamics simulation, and in particular relates to a parametric test design platform and method for an air suspension system based on modeFRONTIER joint simulation. Background technology:

[0002] In the fields of vehicle ride comfort analysis, handling stability analysis, fatigue analysis and NVH analysis, vehicle system dynamics simulation technology, as an indispensable technology in vehicle design, can not only reduce the cost of product development and shorten the product development cycle, but also provide a reference for the improvement and optimization of vehicle structure design.

[0003] When studying the factors affecting vehicle ride smoothness, the suspension system is an important factor, and the determination of its related parameters is particularly important. Through a large number of experimental design and analysis, we can find out the influence of suspension system parameters on vehicle ride smoothness, and use this as a basis to optimize the design of suspension system parameters.

[0004] At present, most of the parametric test design methods for air spring suspensions are to parameterize other parameters except air springs, or to use coil springs instead of air springs for parameterization. These methods often cannot obtain the ideal air spring characteristic curve required by ADAMS / Car simulation to improve vehicle driving smoothness. Through modeFRONTIER-based joint simulation, the attribute file of the air spring in the ADAMS / Car simulation model can be directly modified to obtain a more ideal air spring characteristic curve, which provides a basis for the selection and design of the air suspension in the later stage and the improvement of vehicle driving smoothness.

[0005] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention:

[0006] The purpose of the present invention is to provide a joint simulation platform and method for parametric test design of air suspension system based on modeFRONTIER, which can automatically parameterize some parameters of the suspension system, complete parameter modification and input, and control ADAMS / Car to perform smoothness simulation to obtain simulation test design results when analyzing the influence of air suspension system parameters on vehicle driving smoothness. It can greatly save R&D time and cost, and provide a basis for the optimization of air suspension system parameters in the later stage, thereby overcoming the defects in the above-mentioned prior art.

[0007] To achieve the above objectives, the present invention provides a parametric test design platform for air suspension system based on modeFRONTIER joint simulation, which includes the following parts:

[0008] Vehicle / component system dynamics simulation module based on ADAMS / Car: Establish a vehicle / component rigid body system model in ADAMS / Car, respectively establish the front and rear suspension subsystems, steering subsystem, body subsystem, drive transmission subsystem, brake subsystem and tire subsystem, set up and match the corresponding communicators to complete the information interaction between the subsystems, and finally assemble the subsystems together to form a dynamics simulation model of the whole vehicle;

[0009] The air suspension system parameter definition module and simulation output result data processing module based on MATLAB: including the parameter definition module of the rear suspension shock absorber parameters, rear suspension buffer block parameters, air spring parameters, guide arm parameters and air spring installation hard point parameters, as well as the pulse input working condition simulation output result data processing module at different speeds;

[0010] A co-simulation platform for parametric test design of suspension system based on modeFRONTIER: Use modeFRONTIER to define input and output variables, set corresponding constraints and experimental design methods, and perform co-simulation with ADAMS / Car through written command files and batch files;

[0011] Among them, the MATLAB module is connected to modeFRONTIER through an interface, while the whole vehicle multi-body dynamics simulation module based on ADAMS / Car is called by using the simulation command file inside modeFRONTIER, and the parameterization and modification of the air spring suspension system parameters are completed within the modeFRONTIER platform.

[0012] An experimental design method for implementing parameterization of an air suspension system using a parameterized experimental design platform for an air suspension system based on modeFRONTIER co-simulation includes the following steps:

[0013] Step (1): Multi-body dynamics modeling and simulation analysis of vehicle / component system;

[0014] Step (2): Write command files and batch files: control ADAMS / Car to perform simulation and extract simulation result files;

[0015] Step (3): Air suspension system parameterization and ride comfort simulation result data processing: MATLAB is used to perform parameterization of the air suspension system parameters as input variables, and data processing of the extracted vehicle ride comfort simulation results is performed;

[0016] Step (4): Parametric joint simulation modeling of the air suspension system: define the input variables and output variables separately in modeFRONTIER, and set the corresponding constraints; import the attribute files, simulation command files and batch files of the parameters related to the input variables in ADAMS / Car respectively; select the appropriate experimental design method, connect the corresponding interface with MATLAB and the corresponding nodes between each parameter.

[0017] Preferably, in the above technical solution, step (1) is specifically as follows: measuring the hard point coordinates of the rear air spring suspension in CATIA, establishing key hard points in ADAMS / Car according to the measured hard point coordinates, and establishing related components, determining the motion relationship between the components and setting appropriate constraints; the air spring can be first established using the modeling method of the coil spring, and then the coil spring is replaced by the air spring during assembly, and the guide arm and the anti-roll bar are established using the modeling method of a multi-section beam; finally, the various subsystems are assembled to form a multi-body dynamics simulation model of the entire vehicle.

[0018] Preferably, in the above technical solution, step (2) is specifically as follows: using Notepad to write a simulation command file and a batch file in the format of *.cmd; opening the simulation model through the simulation command file, simulating the corresponding working conditions and generating the corresponding simulation result file; starting the simulation command file multiple times through the batch file and overwriting the modified property file with the file before modification, and deleting other unnecessary files in the result file to release memory.

[0019] Preferably, in the above technical solution, the writing of simulation command files can refer to the commands automatically generated in the background when ADAMS / Car performs simulation and exports simulation results, wherein the background commands can be called up by the shortcut key F3 in ADAMS / Car; the writing of batch files can refer to the writing method of batch files, which mainly includes three parts: file overwriting, opening simulation command files, and deleting non-essential result files.

[0020] Preferably, in the above technical solution, step (3) is specifically: writing a *.m file in MATLAB, parameterizing the installation hard points of the rear suspension shock absorber, the rear suspension buffer block air spring, the guide arm and the air spring; extracting the simulation output result file into MATLAB, performing data processing to generate a corresponding result curve, and obtaining the target result according to the smoothness evaluation standard.

[0021] Preferably, in the above technical solution, the parameterization process defines the stiffness coefficient of the rear suspension shock absorber, the stiffness coefficient of the buffer block, the length coefficient of the buffer block, the stiffness difference coefficient of the air spring, the cross-sectional height of the guide arm and the installation hard point parameters of the air spring respectively through the parameter definition module, and completes the parameter modification by modifying and overwriting the corresponding attribute file through modeFRONTIER. MATLAB data processing mainly includes running ADAMS / Car program commands, reading data file commands, importing data commands and corresponding working condition data processing commands.

[0022] Preferably, in the above technical solution, step (4) specifically comprises: based on the modeFRONTIER platform, a joint simulation model is built in combination with ADAMS / Car and MATLAB, experimental design is performed, and sensitivity analysis is performed on the experimental results.

[0023] Preferably, in the above technical scheme, the input variables and output variables of the joint simulation model are defined in modeFRONTIER using input nodes and output nodes while setting relevant constraints, and the modification of the property file and the selection of the test method are also completed in modeFRONTIER; the parameterization of the specific parameters of the rear suspension system and the processing of the simulation results are implemented in MATLAB, and the dynamic simulation process is carried out in the background of ADAMS / Car; the MATLAB module is connected to the modeFRONTIER platform through the corresponding nodes.

[0024] Preferably, in the above technical solution, the experimental design completes the start and end of the experiment by accessing the logical node and selecting the appropriate experimental design method.

[0025] Preferably, in the above technical solution, the sensitivity analysis is performed by analyzing the post-processing module in the modeFRONTIER platform to find out the suspension system parameters that have a greater impact on ride comfort.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] As described above, the parametric test design platform and method of the air suspension system based on modeFRONTIER joint simulation of the present invention have the following beneficial effects: in the present invention, a multi-body dynamics simulation model of the whole vehicle is established through ADAMS / Car multi-body dynamics software for simulation and exporting simulation result files, and input variables, output variables and suspension system parameter modifications are defined through modeFRONTIER, and parameterization and result file data processing are completed using MATLAB, and *.bat batch files are started to call ADAMS / Car to run simulations. Once the joint simulation starts, no human intervention is required during the entire joint simulation process, and the test design can be automatically performed and the results of the test design can be output, which greatly saves development time and development costs; at the same time, by parameterizing the characteristic curve of the air spring, an ideal air spring characteristic curve of a vehicle equipped with an air spring suspension under good smoothness conditions can be obtained, providing a reference for the design of later air springs. Description of the drawings:

[0028] Figure 1 is a flow chart of the method of the present invention;

[0029] Figure 2 A parametric test design platform for an air suspension system based on ride comfort simulation built for an embodiment of the present invention;

[0030] Figure 3 The sensitivity analysis diagram of the suspension system parameters is completed according to the experimental design results of the embodiment of the present invention. Specific implementation method:

[0031] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific operation process are given. However, the protection scope of the present invention is not limited to the following embodiments, and the rest of the experimental designs realized by using this method are within the protection scope of the present invention.

[0032] The present invention discloses a block diagram of an embodiment of a parametric test design platform and method for an air suspension system based on modeFRONTIER joint simulation, such as Figure 1 As shown in the figure, it includes: vehicle multi-body dynamics simulation module based on ADAMS / Car, MATLAB parameter definition and data processing module, and modeFRONTIER joint simulation platform. Among them, the MATLAB module is connected to modeFRONTIER through an interface, while the vehicle multi-body dynamics simulation module based on ADAMS / Car is called by using simulation command files inside modeFRONTIER, and the parameterization and modification of air spring suspension system parameters are completed in the modeFRONTIER platform.

[0033] The parametric test design platform and method of the air suspension system based on modeFRONTIER co-simulation in this embodiment are carried out in the following steps:

[0034] a) Multi-body dynamics modeling and simulation analysis of the whole vehicle / parts system, specifically: using the digital model of the rear air suspension in CATIA to measure its key hard point coordinates; using the hard point coordinates measured in ADAMS / Car to establish relevant hard points, and using the hard points to establish key components such as guide arms, lateral stabilizer bars, thrust rods and air springs; the guide arms and lateral stabilizer bars can be modeled in the form of multi-segment beams, and the air springs can be modeled using the modeling method of coil springs, and then only the coil springs need to be replaced with air springs during assembly. The components are connected through constraints to form subsystems, and finally the subsystems (front and rear suspension subsystems, steering subsystems, drive transmission subsystems, brake subsystems, and tire subsystems) are assembled together to form a dynamics simulation model of the whole vehicle; the drive simulation control file and the road surface file are further used to simulate the smoothness of the whole vehicle, and the vertical acceleration change value at the rear axle of the simulation model at different speeds is derived.

[0035] b) Write simulation command files and batch files. The specific method is: use Notepad to write simulation command files and batch files. The simulation command file includes three parts: open simulation model command, simulate pulse input conditions at different speeds, and export required simulation result data command. After writing, save it in the format of *.cmd file; the batch file includes three parts: attribute file overwrite command, open simulation command file command, and delete unnecessary simulation result file command. After writing, save it in the format of *.cmd file.

[0036] c) parameterization of the air suspension system, specifically by: determining the input variables of the rear suspension parameterization and the output variables of the joint simulation as shown in Tables 1 and 2;

[0037] Variable Name Initial value scope Step Length RS_Damper / Rear suspension shock absorber 1 (0.5，1.5) 0.1 RS_Bumpstop_Stiff / Rear suspension bumpstop stiffness 1 (0.5，1.5) 0.1 RS_Bumpstop_Length / rear suspension buffer block length 1 (0.7，1.4) 0.1 Airspring_C / Air spring stiffness difference coefficient 1 (0.5，1.5) 0.1 LeadingArm_Height / Guide arm cross section height 20mm (15mm, 25mm) 0.1mm Airspring_Hardpoint / Air spring installation hard point position 127.5mm (-15mm, 270mm) 3mm

[0038] Output variables Variable Name V10_RA_Acc Maximum vertical acceleration of rear axle (V=10km / h) V20_RA_Acc Maximum vertical acceleration of rear axle (V = 20km / h) V30_RA_Acc Maximum vertical acceleration of rear axle (V=30km / h) V40_RA_Acc Maximum vertical acceleration of rear axle (V=40km / h) V50_RA_Acc Maximum vertical acceleration of rear axle (V=50km / h) V60_RA_Acc Maximum vertical acceleration of rear axle (V=60km / h)

[0039] The parameterization method of the rear shock absorber is as follows: multiply several key values ​​used for fitting the characteristic curve in the shock absorber's attribute file by a coefficient, indirectly change the damping characteristics of the shock absorber to form a new characteristic curve, and then use the new attribute file to replace the original attribute file to complete the parameter modification; the parameterization method of the buffer block, air spring, guide arm and the hard point installation position of the air spring is similar to the parameterization method of the shock absorber, and the parameter modification is completed by replacing the original attribute file after modifying the attribute file; the characteristic curve of the air spring is relatively special. In order to obtain an ideal characteristic curve, a parameter needs to be defined here: the air spring stiffness difference coefficient C; in the air spring characteristic curve of Adams / car, all y values ​​in the corresponding curve (except the y value when x=0) are subtracted from the corresponding z value and then multiplied by a coefficient, and this coefficient is defined as C;

[0040] d) Data processing of ride comfort simulation results, specifically: importing the result file of ride comfort simulation into the MATLAB data processing module, then performing data processing on the result file to obtain the maximum vertical acceleration values ​​of the rear axle at different vehicle speeds, and finally returning these values ​​to modeFRONTIER to output the target values ​​of the simulation test design;

[0041] e) Build a joint simulation model based on the modeFRONTIER platform in conjunction with ADAMS / Car and MATLAB. The specific method is as follows: set input and output variable nodes in modeFRONTIER, add MATLAB interface to import MATLAB parameter definition and data processing modules, import simulation command files and batch files into modeFRONTIER through relevant nodes, import relevant attribute files and modify the suspension parameters that need to be parameterized, add logical start and end nodes and select the test design method, and connect each node to complete the parametric test design platform of the air suspension system based on ride comfort simulation. Figure 2 As shown;

[0042] f) Suspension system parameter sensitivity analysis based on the results of the joint simulation test design for ride comfort. The specific method is as follows: after the simulation test design is completed, the correlation coefficient matrix diagram of the input variables and the output variables is made using the post-processing module of modeFRONTIER; when the absolute value of the correlation coefficient is less than 0.3, it is considered that there is no correlation between the two variables; when the absolute value is between 0.3-0.8, it is considered that there is a correlation between the two variables; when the absolute value is greater than 0.8, it is considered that there is a strong correlation between the two variables. A positive value indicates a positive correlation, and a negative value indicates a negative correlation; Figure 3This is a sensitivity analysis diagram of suspension system parameters based on smoothness. According to the sensitivity analysis results, it can be seen that the stiffness of the air spring has a great influence on the pulse smoothness at different vehicle speeds. Reducing the stiffness of the air spring can reduce the maximum vertical acceleration of the rear axle and improve the smoothness of the target vehicle. In addition, there is a strong correlation between the output variables, and the output variables can be reduced for experimental design in the later stage.

[0043] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. An experimental design method for parameterizing an air suspension system using a parametric experimental design platform for an air suspension system based on modeFRONTIER co-simulation, comprising the following steps: Step (1): Multi-body dynamics modeling and simulation analysis of vehicle / component systems; Step (2): Write command files and batch files to control ADAMS / Car to perform simulation and extract simulation result files; Step (3): Air suspension system parameterization and ride comfort simulation result data processing: MATLAB is used to perform parameterization of the air suspension system input variables and to perform data processing on the extracted vehicle ride comfort simulation results; Step (4): Parametric co-simulation modeling of the air suspension system: define the input variables and output variables in modeFRONTIER and set the corresponding constraints; import the attribute files, simulation command files and batch files of the parameters related to the input variables in ADAMS / Car; select the appropriate experimental design method, connect the corresponding interface with MATLAB and the corresponding nodes between each parameter; The step (1) specifically comprises: measuring the hard point coordinates of the rear air spring suspension in CATIA, establishing key hard points in ADAMS / Car according to the measured hard point coordinates, establishing related components, determining the motion relationship between the components and setting appropriate constraints; wherein the air spring can be first established by using the modeling method of the coil spring, and then the coil spring is replaced by the air spring during assembly, and the guide arm and the lateral stabilizer bar are established by using the modeling method of a multi-segment beam; finally, the various subsystems are assembled to form a multi-body dynamics simulation model of the whole vehicle.

2. The method for implementing the parametric experimental design of air suspension system based on the modeFRONTIER co-simulation air suspension system parametric experimental design platform according to claim 1 is characterized in that: The step (2) specifically comprises: using Notepad to write a simulation command file in the format of *.cmd and a batch file in the format of *.bat; opening the simulation model through the simulation command file, simulating the corresponding working condition and generating the corresponding simulation result file; starting the simulation command file multiple times through the batch file and overwriting the modified property file with the file before modification, and deleting other unnecessary files in the result file to release memory.

3. The method for implementing the parametric experimental design of air suspension system based on the modeFRONTIER co-simulation air suspension system parametric experimental design platform according to claim 1 is characterized in that: The writing of simulation command files can refer to the commands automatically generated by the background when ADAMS / Car is simulating and exporting simulation results. In ADAMS / Car, the background commands can be called up by the shortcut key F3. The writing of batch files can refer to the writing method of batch files, which mainly includes three parts: file overwriting, opening simulation command files and deleting unnecessary result files.

4. The method for implementing the parametric experimental design of air suspension system based on the modeFRONTIER co-simulation air suspension system parametric experimental design platform according to claim 1 is characterized in that: The step (3) is specifically as follows: writing a *.m file in MATLAB, parameterizing the installation hard points of the rear suspension shock absorber, the rear suspension buffer block air spring, the guide arm and the air spring; extracting the simulation output result file into MATLAB, performing data processing to generate a corresponding result curve, and obtaining the target result according to the smoothness evaluation standard.

5. The method for implementing the parametric experimental design of air suspension system based on the modeFRONTIER co-simulation air suspension system parametric experimental design platform according to claim 1 is characterized in that: The parametric processing defines the stiffness coefficient of the rear suspension shock absorber, the stiffness coefficient of the buffer block, the length coefficient of the buffer block, the stiffness difference coefficient of the air spring, the cross-sectional height of the guide arm and the installation hard point parameters of the air spring through the parameter definition module, and completes the parameter modification by modifying and overwriting the corresponding property files through modeFRONTIER. MATLAB data processing mainly includes running ADAMS / Car program commands, reading data file commands, importing data commands and corresponding working condition data processing commands.

6. The method for implementing the parametric experimental design of air suspension system based on the modeFRONTIER co-simulation air suspension system parametric experimental design platform according to claim 1 is characterized in that: The step (4) specifically includes: building a joint simulation model based on the modeFRONTIER platform, combining ADAMS / Car and MATLAB, conducting experimental design, and performing sensitivity analysis on the experimental results.

7. The method for implementing the parametric experimental design of air suspension system based on the modeFRONTIER co-simulation air suspension system parametric experimental design platform according to claim 1 is characterized in that: The input variables and output variables of the joint simulation model are defined in modeFRONTIER using input nodes and output nodes while setting relevant constraints, and the modification of attribute files and the selection of test methods are also completed in modeFRONTIER; the parameterization of specific parameters of the rear suspension system and the processing of simulation results are implemented in MATLAB, and the dynamic simulation process is carried out in the background of ADAMS / Car; the MATLAB module is connected to the modeFRONTIER platform through corresponding nodes.

8. The method for implementing the parametric experimental design of air suspension system based on the modeFRONTIER co-simulation air suspension system parametric experimental design platform according to claim 1 is characterized in that: The experimental design starts and ends the experiment by connecting to logical nodes and selecting appropriate experimental design methods; the sensitivity analysis finds out the suspension system parameters that have a greater impact on smoothness through the post-processing module in the modeFRONTIER platform.

9. An air suspension system parameterized experimental design platform based on modeFRONTIER co-simulation for implementing the air suspension system parameterized experimental design method of claim 1, characterized in that: It includes the following parts: Vehicle / component system dynamics simulation module based on ADAMS / Car: Establish a vehicle / component rigid body system model in ADAMS / Car, respectively establish the front and rear suspension subsystems, steering subsystem, body subsystem, drive transmission subsystem, brake subsystem and tire subsystem, set up and match the corresponding communicators to complete the information interaction between the subsystems, and finally assemble the subsystems together to form a dynamics simulation model of the whole vehicle; The air suspension system parameter definition module and simulation output result data processing module based on MATLAB: including the parameter definition module of the rear suspension shock absorber parameters, rear suspension buffer block parameters, air spring parameters, guide arm parameters and air spring installation hard point parameters, as well as the pulse input working condition simulation output result data processing module at different speeds; A co-simulation platform for parametric test design of suspension system based on modeFRONTIER: Use modeFRONTIER to define input and output variables, set corresponding constraints and experimental design methods, and perform co-simulation with ADAMS / Car through written command files and batch files; Among them, the MATLAB module is connected to modeFRONTIER through an interface, while the whole vehicle multi-body dynamics simulation module based on ADAMS / Car is called by using the simulation command file inside modeFRONTIER, and the parameterization and modification of the air spring suspension system parameters are completed within the modeFRONTIER platform.

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