WS6-1 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation WORKSHOP 6 NESTED COORDINATE SYSTEMS

WS6-2 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation

WS6-3 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Problem Description u Investigate the nested coordinate system capabilities in MSC.Patran using a satellite model. Rotate the position of the satellite payload relative to a spacecraft platform using nested coordinate systems.

WS6-4 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Suggested Exercise Steps 1. Start MSC.Patran and create a new database. 2. Import the Nastran input file antenna.bdf. 3. Note the existing coordinate systems. 4. Export a.bdf file from Patran. 5. Review the.bdf to see that the coordinate systems are not nested. 6. Change the translation parameters in Patran and export another.bdf file. 7. Review the second.bdf file to ensure that the coordinate systems are nested. 8. Modify the.bdf to rotate the antenna assembly 90 degrees so that the X axis of coord is aligned with the basic Y axis. 9. Save the.bdf file. 10. Open a new database in Patran. 11. Import the modified.bdf. 12. View the rotated model. 13. Explore additional transformations using coord

WS6-5 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Step 1. Create a Database Create a new database. a.File / New. b.Enter coordinates as the file name. c.Click OK. d.Choose Default Tolerance. e.Select MSC.Nastran as the Analysis Code. f.Select Structural as the Analysis Type. g.Click OK. a b e f d c g

WS6-6 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Step 2. Import a.bdf File a.File: Import b.Set the source to MSC.Nastran Input. c.Select the file antenna.bdf. d.Apply. b c a d

WS6-7 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Step 3. Review Existing Coordinate Systems Review the existing coordinate systems. a.Coord defines the position of the base and is defined relative to Coord 0. b.Coord defines the position of the dish and is defined relative to Coord b a

WS6-8 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Step 4. Export a.bdf File a.Analysis: Analyze / Entire Model / Analysis Deck. b.Enter default_translation as the Job Name. c.Click Apply. a b c

WS6-9 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Step 5. Review the.bdf File Review the CORD2R entries at the end of the file. Note that field three is blank, which defaults to the basic coordinate system

WS6-10 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Step 6. Change the Translation Parameters Change the translation parameters to allow nested coordinate systems. a.Analysis: Analyze / Entire Model / Analysis Deck b.Change the job name. c.Click Translation Parameters. d.For Coord Frame Coordinates, set the value to reference frame. e.Click OK. f.Click Apply. a b d e f c

WS6-11 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Step 7. Review the Second.bdf File Note the nested coordinate system. a.Coord now references Coord a

WS6-12 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Step 8. Modify the.bdf File Modify the.bdf file to rotate the antenna assembly 90 degrees. a.Since Coord is nested, we will only need to modify Coord b.The X Axis of Coord should be rotated to align with the basic Y Axis. c.One possible modified coordinate system is shown below. Modified.bdf: Original.bdf:

WS6-13 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Step 9. Save the.bdf File Save the changes that you made to rotate the coordinate systems.

WS6-14 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Step 10. Create a Database Create a new database. a.File / New. b.Enter rotated_antenna as the file name. c.Click OK. d.Choose Default Tolerance. e.Select MSC.Nastran as the Analysis Code. f.Select Structural as the Analysis Type. g.Click OK. a b e f d c g

WS6-15 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Step 11. Import a.bdf File a.File: Import b.Set the source to MSC.Nastran Input. c.Select the file rotated_antenna.bdf. d.Apply. b c a d

WS6-16 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Step 12. View the Rotated Model Note how the antenna dish and base have been rotated.

WS6-17 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation Step 13. Optional: Explore Transformations As an optional exercise, try making rotational and translational changes to the coordiaate systems and view the resulting displacements in Patran.

WS6-18 PAT328, Workshop 6, May 2005 Copyright 2005 MSC.Software Corporation