TUTORIAL 4 CREATING LS-DYNA ENTITIES

Table Of Contents Section Page Step1. Open MSC.SOFY Database. 3 Step2. Set Seat Belt Options. 4 Step3. Create Shoulder Belt. . 5 Step4. Create Lap Belt. 7 Step5. Create Retractor. 8 Step6 . Create Shoulder Extension 9 Note: As in the other tutorials, all menu items that need to be selected will be preceded by a maroon right arrow: >User action. Mouse buttons are indicated as follows: -- 1B = First (left) button -- used for selecting items -- 2B = Second (middle) button -- used for "OK" -- 3B = Third (right) button -- used for View Manipulation & pop-up menus Normally 1B is used, unless otherwise.

Step1. Open MSC.SOFY Database. Launch MSC.SOFY according to your local configuration. Select >LS-DYNA mode from entry screen. Select >File menu >Open>SOFY DB. In the dialog box navigate to the file you created in Tutorial D-3 Click >Open. OR -- if you prefer to use a small model to demonstrate some of the LS-Dyna entity creation, you can use the small decklid model shown in this tutorial. For the decklid: First set the units: Select >Options menu >Units Mgr. In the Units Manager dialog box,: Select the >Standard Units button>choose >NASTRAN (with WTMASS card). Click >OK. When finished >Exit the dialog box. Browse to the file ..../SOFY3.0/SOFY_MASTER2/DEMOS/Tutorials_DYNA/ Tut_D-1_decklid.sof . e

Step2.Define Contact. e c h Let's go to Collection block to look at some LS-Dyna entity types. Click >Type > select >Contacts. Click >Create to bring up a list of available Contact types. Select >AutoSingle Surface. Note in Pick block the various Slave entity types available: Part, Shells for Set, Nodes for Set, Box, etc. Select >Parts (default) > pick >All. Confirm with >2B. Then the card image dialog comes up. Edit the card image by either typing in the fields or double-click to access more options c h

Step3. Create Box. Now in Collection block > change >Type >Box. Then select >Create Choose >Box from list. Now pick two diagonally opposite corner points of the box. A "Modify Box" dialog pops up, allowing you to modify the chosen box dimensions. Make any adjustments needed. Click >Modify and >Exit. d a e

Step4. Create Rigid Wall Flat. In Collection block> change >Type to >RigidWall. Select >Create >Geometric Flat from list. In Pick block, you have several choices of defining the Rigid Wall. You can pick 1, 2, or 3 nodes. If only 1 node is picked, you will have a choice of planes to orient the wall. Try picking one node at the decklid rear (or front of cab model) Confirm with >2B. A pop-up asks you to select the plane -- Choose >YZ Plane. You are then prompted to pick Slave nodes for Rigid Wall. Select >Box in Pick block. Click on the >box you just created. A dialog pops up with the rigid wall data. Modify the dimensions until the wall is sized properly. Click >Modify and >Exit. h b j k m

Step5. Create Sections. a h c i In Collection block> change >Type >Sections. Click >Create. Choose >Section Plane type. You are prompted to pick 1, 2, or 3 nodes. If only 1 node is picked, you will have a choice of planes to orient the section. Let's try that first. Pick a point on the top surface of decklid Confirm with >2B. Then choose >YZ plane. A dialog pops up, showing the preliminary dimensions which you can modify. Now >Create another section, this time using pick entity type of >xyz. Enter in the three points to define the plane: 4500 0 0 4600 0 0 4500 0 500 This section is perpendicular to the other section. Try creating different sections, using one, two, or three points until you get a feel for it. h c i

Step6.Dyna Specific Checks. Modify Rigid Wall to add prescribed motion: In Collection Block >change >Type >RigidWall. Click with >3B over the name of the wall you previously created. Select >Modify to bring up the dialog. Check the box for >Motion. Add the appropriate data in the new fields that become active. Click >Modify and >Exit. Add Global Boundary Conditions: In Collection Block> change >Type to Global BC. Click >Create Choose from menu to create Boundary, Constraint, Initial, or Load cards. Renumber entities in the model : Select >Utilities>ID Mgmt >Model ID Manager. Enter the starting and offset ID numbers, as applicable, for Parts, Grids, Elements, etc. Any entity types that are disabled can be turned to active by checking the box on right side of menu. When ready> click >OK and all selected entities will be renumbered. i If you wish to exclude certain nodes or elements from being renumbered, use the command : Utilities >ID Mgmt >Lock Entitiy ID's. Also found on >Node menu.

Step7.Clean Up Model. a e g Now, to do some model clean up: Select >Utilities >Model Cleanup >Delete Unref. Click >Reverse button to place checks in all boxes. Click >Apply. Watch message area for confirmation of which empty and unreferenced entities have been deleted. Now to merge duplicate materials, properties, and tables: Select >Utilities >Model Cleanup>Merge Duplicate. Check all the the boxes for >Materials, >Properties, >Load Curves, and >Contacts. Click >Apply and watch Message area for confirmation messages. This command will merge duplicates only if the data in all fields are identical. Add Control Cards by changing >Type in Collection block to >Control. Click >Create to access dozens of different CONTROL cards. Likewise, change Type to >Database to create DATABASE related and INCLUDE cards. Perform Miscellaneous model checks: From >Element Menu>Select >Quick Quality>Misc. Checks. These checks diagnose many Dyna-specific problems with the model. e g

Step8.Export Deck / Scene. Let's try exporting a LS-Dyna deck. Let's check the export options: Options >I/O Options >Dyna Opts >Output Options. (Also accessible from >File menu) Similar to the input options panel, you can select / suppress certain cards and entities from being exported. Check the applicable boxes, and >Exit. To write a LS-Dyna deck : Select >File menu>Export >Dyna Model. In the dialog box, give a file name, perhaps "Tut_D4.dyn" . Click >Save. You may wish to export only a portion of the model: Use >Organize command >Keep the only a couple of parts. Click>Done & then >Exit. Go to >File menu >Export >Dyna Scene. Enter a file name, such as "scene_export.dyn“. Open each of the files created in step8-a and Step8-d in Notepad, or similar text editing software to check the contents and units. Exit MSC.SOFY: File >Quit. (Don't save.) a Congratulations!!! You have just completed LS-Dyna Tutorial 4.