workshop 17 introduction to parameters and features · ws17-6 pat302, workshop 17, december 2004...

WS17-1PAT302, Workshop 17, December 2004Copyright2004 MSC.Software Corporation

WORKSHOP 17

INTRODUCTION TO PARAMETERSAND FEATURES


Problem Description This exercise involves in editing Unigraphics features and

parameter values. This requires importing a Unigraphics part file. Itwill not work with a Parasolid xmt model.

Certain features are to be suppressed. A feature, previouslysuppressed, is to be unsuppressed. The value of some parametersare to be changed.


Suggested Exercise Steps1. Create a new database.2. Import a Unigraphics part file.3. Observe certain features of the model.4. Suppress certain features of the model.5. Unsuppress one of the features previously suppressed.6. Edit a parameter value for the base of the model.7. Create a TetMesh for the solid.8. Edit the display features to get a better visual representation for the model.9. Change the diameter of the hole in the part.10. Verify that the copy of the part(model) has been updated.


Step 1. Create a Database

Create a new database.a. File/New.b. Enter test1 as the file name.c. Click OK.d. Choose Default for the

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


Step 2. Import the Unigraphics Part File

Import a Unigraphics part file.a. File/Import.b. Object/Source:

Model/Unigraphics.c. Select key.prt.d. Click on Apply.e. Click OK when the import

summary appears..

a

b

c

d

A warning message similar to the following should appear in the history window: “Importing Unigraphics Features will requirethat the Unigraphics part file be modified to reflect the changes made in PATRAN. Therefore, a copy of the part is made in/tmp/test1_ug_copy/key.prt_msc_test1 prior to import. Please do not remove or modify this copy in any way as subsequentmodel updates are dependent on the undisturbed copy. This copy will not work with any other PATRAN databases.” In otherwords MSC.Patran will make a copy of the part file and place it in a subdirectory titled [database_name]_ug_copy.MSC.Patran must be able to access this part file to modify features. If the part file is not in the same location the user will beprompted for the new location.


Step 3. Observe the Part Features

Before making any changes observethe model and take note of thedifferent characteristics of the part.

a. Change to Iso 1 View.

e

Blends

NOTE: notice that there is a base to thiskey, blends on some of the edges, and ahole in the middle of the protrusion. Theseare the features which will be changedthroughout this exercise.


Step 4. Suppress Some of the Part Features

Remove certain features using thesuppress method.

a. Geometry: Edit/Feature/Suppress.

b. Under Feature List selectCYLINDER(4).

c. Click on Apply.d. Repeat the previous step to

suppress BLENDS (8), (9), and(10) (the blends indicatedearlier).

c

a

b

d

NOTE: the hole disappearsfrom the viewport. Thismethod is known inUnigraphics as suppressing afeature. Also when the featureis selected from the list it ishighlighted in the viewport.This is one means of selectingfeatures. The features canalso be selected from theviewport.


Step 4. Suppress Some of the Part Features (Cont.)

Illustrated here is the Unigraphics model withthe suppressed features.


Step 5. Unsuppress the Hole in the Key

Because the hole plays asignificant role as a feature in thekey it will be necessary tounsuppress the feature.

a. Geometry: Edit/Feature/Unsuppress.

b. Under Feature List selectCYLINDER(4).

c. Click on Apply.

a

b

c


Step 6. Change the Base of the Model

When the Unigraphics model hasbeen created parametricallyMSC.Patran has the capability tomodify the value of the parameters.

a. Geometry: Edit/Feature/Parameters.

b. Click on BLOCK(0) inFeature List.

c. Click in the cellcorresponding to Size X andDefinition.

d. Under Input ParameterDefinition enter 1.5, andpress Enter.

e. Click on OK.f. Click on Apply.

a

b

c

d

e

f


Step 6. Change the Base of the Model (Cont.)

Illustrated above is a before and after representation of the model. Note that the base of the model is thickernow.


Step 7. Mesh the Model

Mesh the solid.a. Elements: Create/Mesh/Solid.b. Set the Elem Shape, Mesher,

and Topology to Tet,TetMesh, and Tet10,respectively.

c. Under Input List selectSolid 1.

d. Uncheck AutomaticCalculation and enter 0.1under Global Edge Length.

e. Click on Apply.

a

b

c

d


Step 8. Edit the Display Features

Erase the Geometry and changeview options.

a. Click on the Plot/Eraseicon.

b. Under Geometryselect Erase.

c. Click on OK.d. Display/Finite Elements…e. Under Show Only Free select

Faces (in Wireframe).f. Click on Apply, then Cancel.g. Viewing/Angles.h. Change the angle by inputting the

following: 49.81 -35.05 -1.93.i. Click Apply, then Cancel.j. Change the render style to

Smooth Shaded.

b

c

e

ad j


Step 8. Edit the Display Features (Cont.)

Illustrated below is the smooth shaded representation of the model.


Step 9. Change the Diameter of the Hole

Change the diameter of the hole.a. Geometry: Edit/Feature/

Parameters.b. Under Feature List select

CYLINDER(4).c. Click in the cell

corresponding to Diameterand Definition.

d. Input 0.8 for Input ParameterDefinition, and press Enter.

e. Click on OK.f. Click on Apply.g. A warning from message

from MSC.Patran shouldappear stating the following:“A change has been…Doyou want to continue?”Select Yes.

a

b

c

d

f

e


Edit the display features for themodel.

a. Click on Reset graphics.

Step 9. Change the Diameter of the Hole (Cont.)

The model should look like the following:


Step 10. Verify the Copy of the Part has been Updated

Quit Patran.a. File / Quit.

a

Next, in a DOS window or a UNIX shell look in the current working directory (where the MSC.Patrandatabase was created). There should be a subdirectory called test1_ug_copy. Located in thissubdirectory is the copy of the UG file which was being worked on. Copy this file to the working directory.


Step 10. Verify the Copy of the Part has been Updated (Cont.)

Create a new database.a. File/New.b. Enter test1b 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 c

d

f

e

g


Step 10. Verify the Copy of the Part has been Updated (Cont.)

Import the copy of theUnigraphics part file.

a. File/Import.b. Object/Source:

Model/Unigraphics.c. Select copy.prt.d. Click on Apply.e. Click on OK.

copy.prt

b

a

d

c

A warning message should appear. Click OK to clear the warning. The Unigraphics Import summary will appear next.Similarly, clear this summary by selecting OK. Note that the part file imported has the same feature and parameter states asthe model that was previously worked on. If this database is imported into another database the current solid geometry of thepart will also be imported, but the features will be inaccessible.

Quit MSC.Patran when the exercise has been completed.

workshop 17 introduction to parameters and features · ws17-6 pat302, workshop 17, december 2004...

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