Home

eta/VPG TRAINING MANUAL

image

Contents

1. attachment points of the suspension Again the user can edit this table to define their particular body attachment points We shall use the default so select OK from the table 13 eta VPG Training Manual EXTRA NODE COORDINATES a eta VPG will prompt ACCEPT EXTRA NODE COORDINATES Y N b answer Yes 8 The suspension model will be displayed based on our defined geometry ESR hy a then eta VPG will prompt USE DEFAULT MASS CG amp INERTIA MOMENT Y N b answer Yes 14 eta VPG Training Manual 3 Auto Generating Tire Models 1 From the Main menu select the TIRE MODEL menu 2 Select GENERATE A tire property menu will be displayed from which the user can change the desired properties TIRE PARAMETERS We shall edit the parameters except for the pressure value and the of tires Edit the following a PRESSURE UNIT 2 MPA b TIRE PRESSURE 0 2 c TIRE NUMBER 4 3 The tire profile will be shown 15 eta VPG Training Manual a eta VPG will prompt DO YOU ACCEPT THIS TIRE PROFILE Y N ABORT b answer Yes c eta VPG will then prompt for tire location DEFINE WHEEL CENTER LOCATION FOR TIRE 1 1 select the NODE option from the Control Keys menu 2 pick the node at the end of one of the 4 spindles for tire 1 Spindle node es 3 repeat step to define location for the remaining 3 tires define in a clock wise or counter clock wise dire
2. ES a Select CREATE and edit the following 1 CARD DESCRIPTION body constraint 2 PIDM PID for part containing the body structure 3 PIDS PID for part containing the chassis suspension body attachment beams body attach e Defining Gravity 1 Select PRE PROCESSOR BOUNDARY CONDITIONS LOAD CURVES BODY CREATE Z ACCELERATION 2 VPG prompts question USE PARTS OPTION TO DEFINE CARD a select NO this will apply gravity to the entire model 3 The BODY LOAD DEFINITION CARD will appear edit the following a CARD DESCRIPTION type in gravity b LCID LOAD CURVE ID 1 DEFINE CURVE OPTION CREATE 2 CURVE DEFINITION CARD a no editing select OK 3 VPG prompts ENTER DATA TIME amp VALUE FOR POINT 1 OR END a enter 0 9810 4 VPG prompts ENTER DATA TIME amp VALUE FOR POINT 2 OR END 30 eta VPG Training Manual a enter 10 9810 5 VPG prompts ENTER DATA TIME amp VALUE FOR POINT 3 OR END a type end 6 The load curve is displayed along with the curves menu 7 EXIT the curves menu e Pre Loading the Suspension 1 Keep ONLY the springs of the suspension On using PART PART ON OFF 2 parts named SPRING 2 Select PRE PROCESSOR ELEMENT MODIFY 3 Pick an individual spring element 4 VPG prompts to modify the nodes of the springs SPRING DIRECTION AT EACH END IS IN D O F 0 0 PICK NODES POINTS FOR ELEMENT a select DONE 5 The ELEMENT DEFIN
3. ITION card appears edit the following on CARD 1 a INITIAL OFFSET user defined pre load amount 24mm Note this pre load amount should be calculated using the body s weight pre spring the spring rate The relative weighting of the front and rear suspensions should also be taken into account based on the position of the body s C G from the front and rear spring attachment points 31 eta VPG Training Manual Engineering Technology Associates Virtual Proving Ground Version 1 0 train vpg 6 Repeat steps 3 thru 5 for the remaining 3 springs 32 eta VPG Training Manual 6 Defining VPG Analysis Control Parameters We have completed the model and defined most of the analysis parameters We will now define the control parameters for the VPG analysis 1 Return to the Main menu and select ANALYSIS 2 Select CONTROL CARDS 33 eta VPG Training Manual a select ENERGY then edit the CONTROL ENERGY cards fields to be the following b select TERM then edit the CONTROL_TERMINATION card to set the analysis termination time 34 eta VPG Training Manual 3 EXIT back to the ANALYSIS menu then select DATABASE ASCI These cards control the output interval for the ascii database files which contain specific analysis result data that can be graphed in the eta VPG GRAPH PLOT menu a select DEFORC and edit the output interval time to be b select GLSTAT a
4. MAIN menu and branches out into sub menus The user selects a sub menu by mouse pick or keyboard entry Descriptions for these menu options are located in their respective sections FILE Importing and exporting data files i e LS DYNA NASTRAN input files PRE PROCESSOR This menu includes the following submenus LINE generation and manipulation of geometry lines points SURFACE generation and manipulation of surfaces ELEMENT generation and manipulation of finite elements NODE generation and manipulation of nodes eta VPG Training Manual ROAD SUSPENSION TIRE MODEL ANALYSIS MODEL CHECKER commands to check a models integrity SET MENU commands to assign nodes and elements to sets BOUNDARY CONDITION commands to define loads initial velocities spc s etc CONSTRAINT commands to define LS DYNA contraint cards MATERIAL commands to define LS DYNA material property cards ELEMENT PROPERTY commands to define LS DYNA element property cards CONTACT INTERFACE commands to define LS DYNA Contact Interface cards DYNA MISC commands to define LS DYNA control cards This menu contains a library of road surface data from which the user can select or define their own This menu contains a library of front and rear suspensions from which the user can select or define their own This menu allows the user to Auto Generate tire models based on user defined tire geome
5. S VOLUME Edit the following a CARD 1 1 title 2 SID part set ID eta VPG Training Manual 3 SIDTYPE ID type 1 PART SET b CARD 2 1 CN Constant Pressure Value MPA or define LCID for time dependent pressure 4 Repeat step 3 for the remaining 3 part sets e Defining Initial Rotational Velocity 1 Turn ONLY all 4 tires ON 2 Create 2 PART_SETs 1st for the 2 front tires 2nd for the 2 rear tires a select PRE PROCESSOR SET MENU PART b VPG prompts ENTER PART SET NUMBER DEFAULT OR E TO EXIT PICK AN ELEMENT OR PART NAME OF A PART c use a MULTI POINT REGION to select all of the parts of the 2 front tires d select EXIT 3 Repeat step 2 and define a PART_SET for the 2 rear tires Note currently LS DYNA will not run if PART_SETs are used to define Velocity cards therefore we must define a Velocity card for each part of each tire 4 Create Local Coordinate Systems for front and rear rotational axes a select UTILITIES IDENTIFY NODE POINT to identify the right front tire spindle attachment node and the right rear tire spindle attachment node b note these 2 node numbers and their X Y Z coords eta VPG Training Manual 5 Create 2 Velocity cards 1st for the front tires PSID 2nd for the rear tires Select PRE PROCESSOR BOUNDARY CONDITIONS INITIAL CONDITION CARDS VELOCITY CREATE GENERATION a edit the following on CARD 1 1 CARD DESCRIPTION user defined 2 STYP SETTYPE 1 PART
6. SET 3 ID ID select PART SET ID corresponding to the set number defined in STEP 2 4 OMEGA ANGULAR VELOCITY road velocity tire diameter b edit the following on CARD 2 1 Xc tire center coord for front tire Local Coord System measured in step 4b 2 Yc tire center coord for front tire Local Coord System measured in step 4b 3 Zc tire center coord for front tire Local Coord System measured in step 4b 4 Nx 0 0 5 Ny 1 0 negative or positive depending on velocity sign and Right Hand Rule of LCS 6 Nz 0 0 6 Repeat step 5 for the rear tire PSID 20 eta VPG Training Manual 4 Auto Generating a Road Surface 1 Select ROAD from the Main menu 2 Choose SELECT FROM LIBRARY a select USER DEFINED b VPG prompts ENTER USER DEFINED ROAD FILE OR STOP TO EXIT l type in road lib 2 select 1 COBBLESTONE 22 eta VPG Training Manual 3 As you will notice after the road model is read in the road is located underneath our suspension model If the road model were not located in the correct position the MOVE ROAD SURFACE would be used to position the road correctly Erapenecee lethecbary Asuxinss Vinal Pasta siase varias Li Hen ope NOT E put the model into a SIDE view Small adjustments may have to be made to the road location by using the PRE PROCESSOR NO DE TRANSFOR M comm and to transform the nodes of the road up or down in the global Z direction Th
7. an submit the analysis 1 From the ANALYSIS menu select DYNA INPUT FILE OPTIONS and edit the following DYNA INPUT FILE OPTIONS _CUARENT SYSTEM _ Eee r E Cancel a Input File Name train dyn b Analysis Title VPG Training c Engineers Name your name here 2 The user can now select whether to submit the analysis directly from the window or write out the input file without submission LS DYNA should be installed and setup on the workstation to submit analysis directly from the eta VPG window We will write out the input file and take a look at how it is setup and because of time requirements we will not run the analysis We will post process results that have been already run a click on WRITE INPUT FILE then click OK The LS DYNA input file will be written out with the name train dyn The user should vi this file to see how it has been setup x lt 38 eta VPG Training Manual Note The user should reference the eta VPG User Processor Manual for information on how to submit the analysis from outside eta VPG and how to use the control Sense switches when LS DYNA is running The user should also reference how to Restart files d3dump and runrsf and reference the terminology of other various LS DYNA files 39 eta VPG Training Manual 8 Displaying Results We will now post process the results from our analysis RESTART the eta VPG session and CREATE A NEW FILE call
8. ction from tire 1 eta VPG Training Manual e Attaching Tires to the Suspension 1 When generating the tires they will be moved to the ends of each spindle by the user pick 2 Turn all parts OFF except the parts containing the wheel hubs rim and spindles for each tire 3 ZOOM into the 1st tire 4 COPY the 2 coincident nodes that define the middle of each hub and end of each spindle 10 mm outboard either or Y direction depending on which side of the vehicle 5 TRANSFORM 1 of the copied coincident nodes 10 mm to the left or right of the other so you can see both of them 6 Go to the ELEMENT options menu and select CREATE JOINT REVOLUTE 7 Use a RELATIVE PENALTY STIFFNESS 1 0 eta VPG Training Manual 8 Define the joints nodes as follows 1 3 4 2 where node 1 end of spindle node 2 free node node 3 center of hub node 4 free node NOTE node 2 and 4 it doesn t matter which free node is which 9 Reverse step 5 to move the free nodes back together coincident 10 Repeat the above steps for the 3 remaining tires e Defining Airbags for Tire Pressure l Create a PART SET for each tire including ALL parts of the tire the hub rim under PRE PROCESSOR SET MENU PART CREATE 2 Repeat step 1 for each tire so you will end up with a total of 4 part sets 3 Define an airbag for each part set created under PRE PROCESSOR DYNA MISC AIRBAGS CREATE SIMPLE PRES
9. e goal is to have 1 to 2 mm gap between the tires and road surface no penetration This distance can be checked by using the DISTANCE NODE PT command in the UTILITIES menu e Defining Contact between Road and Tires 1 Turn ONLY the outer tread part of each tire and the road surfaces ON 2 Select PRE PROCESSOR CONTACT INTERFACE CREATE 3 DIMENSIONAL 23 eta VPG Training Manual 3 Select 5 NODES_TO_SURFACE interface type 4 Edit the following a CARD 1 1 CARD DESCRIPTION eg tire 1 b CARD 2 1 SSID SLAVE ID tire 1 PID 2 MSID MASTER ID road PID 3 SSTYP SLAVE TYPE ID type 3 PART 4 MSTYP MASTER TYPE ID type 3 PART c CARD 3 1 FS STATIC FRICTION COEFF 0 7 2 FD DYNAMIC FRICTION COEFF 0 7 5 Use the COPY command to copy the 1st interface card to generate cards for the remaining 3 tires Edit the CARD DESCRIPTION CID contact interface ID and SSID for each respective tire e Constraining the Road 1 Turn ONLY the Road Surface ON 2 Select PRE PROCESSOR MATERIAL 3 Select DEFINE PROPERTIES and pick the material assigned to the road 4 The material card appears edit the following on CARD 2 a CON1 5 b CON2 7 24 eta VPG Training Manual Note this will constrain the road in the Y Z and all rotational directions e Assigning Velocity to the Road 1 Select PRE PROCESSOR BOUNDARY CONDITIONS BOUNDARY CARDS PRESCRIBED MOTION CREATE RIGID BODY 2 Edit the following
10. ed pp vpg pp for post processing 1 From the Main Menu select POST PROCESSING a select D3PLOT LS DYNA result file b select the file d3plot from the File Menu c select LS DYNA version 940 d select ALL AVAILABLE STEPS 40 eta VPG Training Manual e select ALL COMPONENTS The results from each of the 10 steps will then be read into eta VPG A binary result file will be created at this time named d3plot pp Since the results are not saved to the eta VPG database this binary file should be re read into the post processing menu when the user wishes to view the results again This file is read much faster than the d3plot files 2 The Post Processing menu is now displayed 41 eta VPG Training Manual 3 Put the model into an ISO metric view and select ANIMATE DEFORMATION 4 Select EVEN steps from the menu and then ANIMATE 6 EXIT out of the animation menu then select ANIMATE CONTOUR 42 eta VPG Training Manual 7 Select EVEN steps and MAX_VONMISES contour variable Then pick ANIMATE a ZOOM into the front tires to see the stress distribution in the wheel we will not see any stress contours in the body model again this is because the body is rigid in this analysis 43 eta VPG Training Manual During the animation the user can select INDIVIDUAL FRAME to scroll thru each result frame increase decrease the animation
11. el 7 2 Auto Generating a Rear Suspension Model 11 3 Auto Generating Tire Models 15 e Attaching Tires to Suspension 18 e Defining Airbags for Tire Pressure 19 e Defining Initial Rotational Velocity 20 4 Auto Generating a Road Surface 22 e Defining Contact between Road and Tires 25 e Constraining the Road 26 e Assigning Velocity to the Road 26 5 Attaching a Body Model to Chassis Suspension model 28 e Defining Gravity 30 e Pre loading the Suspension 31 Table of Contents eta VPG Training Manual Dynamic Analysis 6 Defining VPG Analysis Control Parameters 7 Analysis Submission Post Processing 33 38 8 Displaying Results 9 Graph Plotting Conclusion 40 46 49 Table of Contents eta VPG Training Manual Introduction This training manual was created to familiarize new users with the eta Virtual Proving Ground VPG software The exercise will show the user how to Auto Generate suspension front rear tire and road models using the VPG libraries A Simplified Body will be added the full system model will be analyzed and the results post processed eta VPG Menu System The menu system is an open system Most operations are accessible at any time during the eta VPG session The user interface consists of four parts the Drawing window Menu window Dialogue window View Options window and Display Parameter Options window The menu system is set up as a tree structure The program starts in the
12. eta VPG TRAINING MANUAL A LS DYNA based Full Vehicle Simulation Solution Package Version 1 0 Release Date August 19 1998 FORWARD The concepts methods and examples presented in this text are for illustrative and educational purposes only and are not intended to be exhaustive or to apply to any particular engineering problem or design This material is a compilation of data and figures from many sources Engineering Technology Associates Inc assumes no liability or responsibility to any person or company for direct or indirect damages resulting from the use of any information contained herein Engineering Technology Associates Inc Creation Date January 15 1997 Revision Level 1 Revision Date April 7 1997 Approved by Bob Ondrus eta VPG Training Manual Version 1 0 Engineering Technology Associates Inc 1100 East Mandoline Suite B Madison Heights MI 48071 Phone 248 588 9010 Support 800 ETA FEMB Fax 248 588 9014 Engineering Technology Associates Inc ETA the ETA logo and eta VPG are the registered trademarks of Engineering Technology Associates Inc All other trademarks or names are the property of the respective owners Copyright 1998 1999 Engineering Technology Associates Inc All rights reserved eta VPG Training Manual TABLE OF CONTENTS Introduction 1 eta VPG Menu System 1 Opening Creating an eta VPG Database File 5 Pre Processing 1 Auto Generating a Front Suspension Mod
13. fine their particular bushing rates We shall use the default so select OK from the table DAMPING COEFFICIENT 7 An Extra Node Coordinate menu will then be displayed in which the user can specify the coordinates of the body attachment points of the suspension Again the user can edit this table to define their particular body attachment points We shall use the default so select OK from the table eta VPG Training Manual EXTRA NODE COORDINATES a eta VPG will prompt ACCEPT EXTRA NODE COORDINATES Y N b answer Yes 8 The suspension model will be displayed based on our defined geometry B a the eta VPG will prompt USE DEFAULT MASS CG amp INERTIA MOMENT Y N b answer Yes 10 eta VPG Training Manual 2 Auto Generating a Rear Suspension Model 1 From the Main menu select the SUSPENSION menu 2 Select CREATE A suspension menu will be displayed from which the user can select different types of front and rear suspension models 3 For the REAR SUSPENSION select type 2 H ARM 11 eta VPG Training Manual STABILIZER ATTACHMENT W LOWER ARM _ SPINDLE Cancel Abort The user can select the Stabilizer attachment point location 4 The suspension geometry will be displayed along with a table listing the coordinates of nodes that define the geometry The user can edit this table to define their particular suspension geometry We shall use the defau
14. formable Body In this case the specific coordinates for the body attachments points would have be entered when the user defined the Extra Node Coordinates for the front rear suspension models procedures 1 amp 2 step 7 This would ensure that the generated suspension would fit the specific body model The user would create weld spiders between the mounts on the vehicle and the rigid body beams on the suspension 28 eta VPG Training Manual Engineering Technology Associates Virtual Proving Ground Version 1 0 train vpg C DY AY 3 We will assign a rigid material to the body model for this example Select PRE PROCESSOR MATERIAL a Select CREATE STRUCTURAL and choose type 20 1 MAT_RIGID 1 Edit the CARD DESCRIPTION field on CARD to be body mat b ASSIGN MATERIAL to the body model the model should turn the color of the property We will define a new part to contain all of the body attachments on the chassis suspension CREATE NEW PART under the PART menu called body attach a Use the ADD ELEMS TO PART command and move all the beam elements in suspension parts with the name BODY to this new part body attach 6 We will now re assign a rigid material to this new part Nn 7 29 eta VPG Training Manual Select any existing RIGID material property card and ASSIGN it to the part body attach 7 We will constrain the 2 rigid bodies together Select PRE PROCESSOR CONSTRAINT RIGID BODI
15. is table to define their particular spring rates We shall use the default so select OK from the table ITEMS SPRING DIRECTION STIFFNESS OF SPST_U STIFFNESS OF SPLA_F STIFFNESS OF SPLA_R STIFFNESS OF SPSZ_B STIFFNESS OF SPRING DATA AXIAL CONICAL ORSAIONAL 1 000000E 03 1 000000E 03 1 OOO000E 03 1 000000E 03 4 000000E 03 4 000000E 03 4 000000E 03 14 000000E 03 11 000000E 03 1 000000E 03 14 000000E 03 4 000000E 03 1 000000E 03 1 000000E 03 2 500000E 01 4 000000E 03 4 000000E 03 oK 6 A Damping Coefficient menu will then be displayed in which the user can specify the bushing rates of the suspension Again the user can edit this table to define their particular bushing rates We shall use the default so select OK from the table TEENS SPRING DIRECTION STIFFNESS OF SPST_U STIFFNESS OF SPLA_F OF SPLA_R OF SPSZ_B SPRING STIFFNESS STIFFNESS STIFFNESS DATA AXIAL RADIAL CONICAL TORSAIONAL 1 000000E 03 1 000000E 03 11 000000E 03 1 000000E 03 4 000000E 03 4 000000E 03 4 000000E 03 4 000000E 03 1 000000E 03 1 OO0000E 03 4 Q000000E 03 4 000000E 03 1 000000E 03 1 000000E 03 2 500000E 01 4 000000E 03 14 000000E 03 Cancel An Extra Node Coordinate menu will then be displayed in which the user can specify the coordinates of the body
16. lt so select OK from the table rl TEMS rDATA NODE 01 Coord mm 2 580000E 03 6 500000E 02 2 500000E 02 NODE 02 Coord mm 2 300000E 03 2 000000E 02 2 500000E 02 NODE 03 Coord mm 2 700000E 03 2 000000E 02 2 500000E 02 NODE 04 Coord mm 2 550000E 03 6 500000E 02 2 500000E 02 NODE 05 Coord mm 450000E 03 6 500000E 02 2 500000E 02 NODE 06 Coord mm 2 500000E 03 5 900000E 02 2 500000E 02 NODE 07 Coord mm 2 500000E 03 5 900000E 02 3 000000E 02 NODE 08 Coord mm 2 512000E 03 5 450000E 02 5 120000E 02 NODE 09 Coord mm 2 539000E 03 4 970000E 02 8 330000E 02 NODE 10 Coord mm 2 270000E 03 3 000000E 02 2 750000E 02 NODE 11 Coord mm 2 270000E 03 4 500000E 02 2 600000E 02 NODE 12 Coord mm 2 450000E 03 5 000000E 02 2 800000E 02 NODE 13 Coord mm 2 420000E 03 6 500000E 02 2 500000E 02 NODE 14 Coord mm 2 500000E 03 6 500000E 02 3 500000E 02 NODE 15 Coord mm 2 500000E 03 7 500000E 02 3 500000E 02 NODE 16 Coord mm 2 539000E 03 4 500000E 02 8 330000E 02 NODE 17 Coord mm 2 539000E 03 5 500000E 02 8 330000E 02 Ok Cancel a eta VPG will prompt ACCEPT THESE GEOMETRY DATA Y N b answer Yes 12 eta VPG Training Manual 5 A Spring Stiffness menu will be displayed in which the user can specify the spring rates of the suspension Again the user can edit th
17. menu the user will be prompted to save the graphs QUIT TIME HISTORY a if the user selects to save the graphs they will be prompted PLEASE INPUT BINARY FILE NAME lt fembth gr gt b the graph info will be saved to this file and like the d3plot pp file the graph file can be re read at a later time without having to re read the database file s 48 eta VPG Training Manual Conclusion This concludes the eta VPG training manual The user should now have a basic understanding of how to create an eta VPG model setup the analysis and post process the results Reference the Applications Manual for specific information about analyses and the User s Manual for more detailed description of commands 49
18. nd edit the output interval time to be 5 0e 3 sec 35 eta VPG Training Manual c select JNTFORC and edit the output interval time to be 5 0e 3 sec d select NODOUT and edit the output interval time to be 5 0e 3 sec e select RBDOUT and edit the output interval time to be 8 0e 3 sec f select RCFORC and edit the output interval time to be 5 0e 3 sec 4 EXIT back to the ANALYSIS menu then select DATABASE BINARY These cards control the output interval of the binary database files for results d3plot and restarts d3dump and runrsf DATABASE BINARY CARD ACTIVE a select D3PLOT and edit the output interval time to be b select D3DUMP and edit the output frequency to be 9 99E 08 36 eta VPG Training Manual Users should be aware that these files can be fairly large and since consecutive files are written based on the frequency i e d3dump d3dump01 d3dump02 users have to be careful not to fill up their hard disk c select RUNRSF and edit the output frequency to be 5 0E 03 Unlike the d3dump file which is written consecutively the runrsf file is overwritten based on the frequency only 1 runrsf will exist although it will increase in size each time Therefore using this file is safer then using the d3dump file is hard disk space is a consideration 37 eta VPG Training Manual 7 Analysis Submission Now that we have completed defining our analysis control cards we c
19. rawing Window geometry models and graphs are displayed in this window 2 Menu Window menus are listed Menus can be selected with a left mouse click 3 Dialogue Window messages are displayed here and commands can be typed at the prompt 4 View Options window the PART SETUP and UTILITIES menus are selectable here along with view manipulation commands 5 Display Parameters Options window display parameters such as shading fill color hide along with REDRAW and RESET are selectable ame Menu window s Drawing window e View Options r Display Parameters window y zer Options window eta VPG Training Manual Opening Creating an eta VPG Database File Type vpg in a Unix window to start the program Once the windows are activated the VPG FILE MENU window is displayed for the user to OPEN or CREATE a new VPG database 1 YPG File Menu 2 The user would either select the name of a previously saved file or enter the name of a new file in the Dialogue window The recommended practice is to add the extension vpg to a newly created file 3 Ifcreatinga NEW file the user would be prompted to do so eta VPG Training Manual pa 4 The user will be prompted to select the analysis program desired The analysis program selected will set defaults for the eta VPG session to generate either LS DYNA or NASTRAN cards 5 The user will also be prompted to select the Unit System desi
20. red The user will now be in the MAIN MENU of eta VPG and ready to start the session eta VPG Training Manual eta VPG Training Manual 1 Auto Generating a Front Suspension Model 1 From the Main menu select the SUSPENSION menu 2 Select CREATE A suspension menu will be displayed from which the user can select different types of front and rear suspension models eta VPG Training Manual 3 For the FRONT SUSPENSION select type 2 McPherson A ARM MACPHERSON SUSPENSION OPTION The user can select the Steering System Stabilizer types and whether or not there is a Strut Bar in the above table 4 The suspension geometry will be displayed along with a table listing the coordinates of nodes that define the geometry The user can edit this table to define their particular suspension geometry We shall use the default so select OK from the table SUSPENSION GROMETRY DATA eta VPG Training Manual a eta VPG will prompt ACCEPT THESE GEOMETRY DATA Y N b answer Yes 5 A Spring Stiffness menu will be displayed in which the user can specify the spring rates of the suspension Again the user can edit this table to define their particular spring rates We shall use the default so select OK from the table _ SPRING STIFFNESS 6 A Damping Coefficient menu will then be displayed in which the user can specify the bushing rates of the suspension Again the user can edit this table to de
21. speed TURN PARTS ON OFF and SAVE MPEG files which can be played on most PC s and workstations without having the eta VPG program 8 Select DISPLAY OPTION Turn the ELEMENT OUTLINE off change the CONTOUR BAR ORIENTATION to HORIZONTAL change the CONTOUR LEVEL to 25 and change the UPPER RANGE to 400 MPA then ree ANIMATE 44 eta VPG Training Manual ee ew ee Poe Ore Gave MER OO DOERETPE eH ee eunea vee 45 eta VPG Training Manual 9 Graph Plotting 1 We will not plot some LS DYNA ASCII database results graphically EXIT out of the Post Processing menu 2 Select GRAPH from the Main Menu then select CREATE NEW FILE from the FILE MENU 3 Select GLOBAL DATA and choose the filename glstat from the FILE MENU 46 eta VPG Training Manual 4 Select KINETIC and TOTAL ENERGY from the variable list SELECT VARIABLES TIME STEP KINETIC ENERGY INTERNAL ENERGY SPRING AND DAMPER HOURGLASS ENERGY SYSTEM DAMPING EN SLIDING INTERFACE EXTERNAL WORK TOTAL ENERGY TOTAL ENERGY IN GLOBAL X VELOCITY GLOBAL Y VELOCITY GLOBAL Z VELOCITY ad E UNDO ABORT DONE 5 The graph of the energies will be displayed The TIME HISTORY PLOTS menu can then be used to manipulate the graph s and also read more graphs into the database a total of 16 graphs can be read into an individual database 47 eta VPG Training Manual 6 Upon EXITING the TIME HISTORY PLOTS
22. to the BOUNDARY_PRESCRIBED_MOTION card a CARD DESCRIPTION e g road vel b PID PART ID road PID c VAD VELOCITY ACCEL DISPL O velocity d LCID LOAD CURVE ID 1 DEFINE CURVE OPTION CREATE 2 CURVE DEFINITION CARD a no editing select OK 3 VPG prompts ENTER DATA TIME amp VALUE FOR POINT 1 OR END a enter 0 16000 mm s 4 VPG prompts ENTER DATA TIME amp VALUE FOR POINT 2 OR END a enter 10 16000 mm s Note the time value of 10 secs is arbitrary we will not be running the job for that long 5 VPG prompts ENTER DATA TIME amp VALUE FOR POINT 3 OR END a type end 6 The load curve is displayed along with the curves menu 7 EXIT the curves menu 25 eta VPG Training Manual 26 eta VPG Training Manual 5 Reading the Simplified Body Model The body to chassis suspension attachment process depends upon what type of body model the user wishes to use for analysis deformable or rigid For this training example we will use a simple rigid body model to represent the car structure but instructions will also be given on how to use a deformable body 1 From the Main Menu select FILE 2 Read in the NASTRAN file called body nas Again this is a simplified body model that will be made rigid Rigid Body In this case we will constrain the rigid body model to the rigid beams that define the body attachment points on the suspension De
23. try parameters The user can define LS DYNA analysis control parameters then submit the job to run in the background interactively or write an input file directly eta VPG Training Manual FATIGUE FFT POST PROCESSING GRAPH RESTART SESSION FILE VIEW EXIT PROGRAM Menu that contains commands for viewing analysis results deformed shape contour plotting amp animation LS DYNA ASCII result files which contain the dynamic characteristics of the analyzed model vs time can be read and plotted Once read the data can be manipulated using an array of commands Allows the user to restart without saving the current database from the current a new or an existing database Allows the user to regain lost work i e system crash thru reading a short executable that is saved ina file called VPG ses Commands for manipulating a model s display position and perspective in eta VPG Exits eta VPG Function keys 1 thru 8 are also available to jump to the most frequently used menus The F1 function key 1 is reserved for the MAIN menu F1 Main Menu F5 Model Checker F2 Element Options F6 Node Options F3 File Manager F7 Surface Options F4 Geometry Builder F8 Free Rotation eta VPG Training Manual eta VPG is composed of 5 motif widows The 5 windows are described and illustrated below the Drawing window Menu window Dialogue window View Options window and Display Parameter Options window 1 D

Download Pdf Manuals

image

Related Search

Related Contents

MN220 Series  Fisher-Price 74120 Instruction Sheet  取扱説明書  Utility light User Guide.indd - Solar Technology International  Manual Balboa SZ  Vapor ozono frances  Configuring the SIMATIC Field PG - Internet    Sunbeam SR8600 Iron User Manual  HDC-SD707 HDC-TM700 HDC  

Copyright © All rights reserved.
Failed to retrieve file