Sketch Mode

1
Sketch Mode

• Chapter 3

2
Sketch ModeContents

• DesignModeler Geometry
• Length Units
• DesignModeler Geometric Entities
• Sketch Mode
• New Plane Button
• New Sketch Button
• From Face Plane/Sketch
• The Sketch Mode GUI
• Planes and Sketches
• Plane Transforms
• Sketching Tools
• Sketching - Basic Shapes
• Sketch Details

• Sketch Constraints
• Sketch Dimensions
• Dimension Editing
• Workshop 3-1, Sketching
• Modifying Sketches
• Sketch Instance
• Geometry Interfaces
• Attaching to a CAD Session
• Importing CAD Files
• Positioning Imports
• Import Units
• Exporting a Model
• Body Attributes
• Workshop 3-2, 3D Geometry

3
Sketch ModeDesignModeler Geometry

• To study DesignModeler geometry well focus on
  four fundamental areas
• Sketch mode
• Contains tools to create 2D geometric shapes as a
  prerequisite to 3D geometry creation or concept
  modeling.
• 3D Geometry
• Geometry derived from sketch entities such as
  extrusions, revolves, surface models, etc.
• Geometry import
• Geometry originating from a commercial CAD
  system. Typically imported into DM to allow
  modification for FE meshing.
• Concept modeling
• These tools are used to create and modify line
  and surface bodies which can be used as the basis
  for FE beam and shell models.

4
Sketch ModeLength Units

• When a new DM session is started a dialog box
  allows selection of the desired length unit (can
  be set as default)

5
Sketch ModeDesignModeler Geometric Entities

• Points
• 2D Sketch Points
• 3D Vertices
• PF Points (Point Features)
• spot-welds
• point loads
• construction points
• Edges (Lines, Curves)
• 3D, and 2D Sketch
• Faces (Areas, Surfaces)
• Bodies (Volumes)
• Multiple bodies
• (not shown)

S
6
Sketch ModeSketch Mode

• DM sketches are created on planes. In a new DM
  session there are three default orthogonal planes
  in place at the global origin (XY, ZX, YZ).
• Users may create and position new planes as
  needed by defining origin and orientation or by
  using existing geometry as a reference.
• The process to begin sketching is twofold
• Identify the plane upon which you wish to sketch.
• Create or identify the sketch which lies on the
  desired plane.
• Users may create as many planes as needed.
• Each plane may have multiple sketches associated
  with them.
• In the next few pages well look at plane and
  sketch entity creation and tools to assist in
  sketching.

7
GUI - Graphical User InterfaceNew Plane Button

• gtNew Plane creates a new plane
• New plane object is placed in the Tree
• Six types of plane construction (Detail Pane)
• From Plane new plane is based on another
  existing plane
• From Face new plane is based on a face
• From Point and Edge new plane is defined by a
  point and a straight line edge
• From Point and Normal new plane is defined by a
  point while its normal is defined by an edge
  direction
• From Three Points new plane is defined by three
  points
• From Coordinates new plane is defined by typing
  in the coordinates of the origin and normal
• Sketches are then added to plane
• A sketch is utilized to create 3D geometry

8
GUI - Graphical User InterfaceNew Sketch Button

• New Sketch creates new sketch on the
  active plane.
• New sketches are placed in Tree beneath their
  associated Plane.
• Navigate sketches (make active) via the Tree or
  drop down list.
• Note drop down list references sketches on
  currently active plane (see example below).

Only XYPlane sketches displayed in drop down
XYPlane is active
9
GUI - Graphical User InterfaceFrom Face
Plane/Sketch Shortcut

• Shortcut to create a new From Face plane and
  sketch using existing geometry
• Highlight desired surface to place new plane.
• Switch to the Sketch tab and begin sketching.
• New plane and sketch are automatically created!

10
Sketch ModeThe Sketch Mode GUI

• In sketch mode the GUI presents sketching
  toolboxes to the left through a series of
  panels.

Plane and sketch creation and management
Draw Panel
At the beginning of a new session the XY plane is
displayed at the origin.
ToolBox Panels
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Sketch ModePlanes and Sketches

• The active plane is highlighted in the tree and
  shown in the drop down list.
• Active plane can be changed from either location.
• Clicking the New Plane button results in a
  plane being created.
• The same functionality and behavior applies to
  sketch creation and manipulation.
• Note that each sketch will be associated with a
  plane.

12
Sketch ModePlanes and Sketch Details
The plane origin can be turned on/off.
After setting plane details, the Generate
button creates the new plane. Note this step is
not necessary for sketch creation. Can Generate
with RMB
The Details for each plane and sketch controls
basic behavior.
Triad
Ruler
The triad and display ruler can be turned on/off.
13
Sketch ModePlane Transforms

• Up to 9 plane transformations are available.
  They can be applied quickly by choosing the
  desired transform through the RMB in the
  Transform field in the plane detail window.

14
Sketch ModePlane Transforms

• Once a transform is selected, additional
  properties may appear that will allow you to
  enter offset distances, rotation angles, rotation
  axes, etc.

This transform requires both an offset and a
rotation angle.
PLANE4
To add an additional transform, set Additional
Transform? to Yes.
15
Sketch ModeSketching Tools - Grid

• The Settings panel allows a sketch grid to be
  defined and displayed (default off).
• Snap feature applies to major and minor spacing.

Major spacing (solid)
Minor spacing (dashed)
16
Sketch ModeSketching Tools Grid

• Grid Snaps per Minor allows snapping to points in
  between minor grid lines.

This rectangle is snapped halfway between two
minor grid lines.
17
Sketch ModeSketching Tools Ruler

• The Ruler tool allows you to get a quick sense of
  scale.

18
Sketch ModeSketching Tools Auto Constraints

• By default DM is in auto-constraint mode.
• Auto constraints allow new sketch entities to
  automatically snap to a location or orientation.
• The cursor indicates the kind of constraint that
  will be applied.
• Examples
• (see documentation for complete list)

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Sketch ModeSketching Tools Tips

• When creating or changing planes and sketches the
  Look At tool will immediately orient the
  display so that the plane, sketch or selected
  entity is normal to your view.
• Many operations either require or are more
  efficient via a right mouse click context menu
  from the graphics screen.

Right mouse click RMB
20
Sketch ModeSketching Tools Tips

• The Undo/Redo buttons are available in sketch
  mode only.
• Removes the last completed sketching operation.
• Multiple undos allowed.
• IMPORTANT Each plane stores its own Undo
  stack.
• The Back operation (available via RMB) acts
  like a micro undo during sketching operations.
• Remember only one sketch is active at any time!

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Sketch ModeSketching Tools Tips

• The GUI status bar contains instructions on
  completing each operation.
• Example using the circle operation . . .

1. Choose Circle

1. Follow instructions in status bar choose
   location for center point

1. Follow instructions in status bar drag and
   release for radius

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Sketch ModeSketching Basic Shapes

• Once a plane and sketch have been specified you
  can begin creating new geometry from the Draw
  toolbox.
• Remember! Some operations will require a right
  click to complete!
• Example to end a spline operation use the RMB
  to choose the desired option.

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Sketch ModeSketch Details

• Reference numbers for the entities in each sketch
  (lines, circles, polygons, etc.) can be viewed.
• Useful for parametric modeling discussed later.

Can rename sketches from Detail pane.
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Sketch ModeSketch Details

• Highlighting lines in the graphics screen (sketch
  mode only), will display details for the line.

Can rename sketch entities from Detail pane.
Details for highlighted line
25
Sketch ModeSketch Constraints

• Sketch details can also display sketch constraint
  details.
• Constraints may result from auto-constraints or
  user defined.
• To delete constraints, highlight the definition
  and use the delete key.

Show constraints
Constraint definitions
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Sketch ModeSketch Constraints . . .

• Sketch entities are also color coded to indicate
  their current constraint status
• Teal Under-constrained
• Blue Well Defined
• Black Fixed
• Red Over-Constrained
• Gray Inconsistent or Unknown
• Example
• Initially sketched lines are displayed in teal
  color to indicate under-constraint. Note even
  when dimensioned, these lines are
  underconstrained since they are not fixed in
  space
• Adding 2 more dimensions resolves the sketch
  status and all lines are displayed in blue

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Sketch ModeSketch Constraints . . .

• By adding too many dimensions and/or constraints
  the sketch will become over constrained. Over
  constrained lines are displayed in red in sketch
  mode
• Applying Fixed constraints to 2 of the edges
  shown here results in the lines being displayed
  in black

Red
Blue
Red
Teal
Black
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Sketch ModeSketch Constraints . . .

• The picture below demonstrates an inconsistent
  situation (lines displayed in gray). Here the
  arc is dimensioned with a radius of 5 however the
  vertical dimension has been specified as 15.
  Obviously there is no way to maintain the
  connection between the 2 horizontal lines and the
  arc while maintaining these dimensions.

Gray
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Sketch ModeSketch Dimensions

• DesignModeler contains a complete dimensioning
  toolbox.
• In addition to individual dimension assignment,
  semi-automatic dimensioning is available.
• Semi-automatic cycles through dimension choices
  until model is fully constrained or user chooses
  to exit semi-automatic mode.
• Right mouse button controls skip or end
  functions.
• The General dimensioning tool allows quick access
  to all primary dimensions via a right click
  context menu.

Right Mouse Click
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Sketch ModeSketch Dimensions

• Move function allows placement of dimension to be
  modified.
• Animate to view dynamic changes applied to the
  selected dimension.
• Dimensions can be displayed as the dimension
  value or name.

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Sketch ModeSketch Dimensions

• To modify dimensions highlight then change value
  in details window.

Highlight dimension
Enter new value
32
Sketch ModeDimension Editing

• Once highlighted, dimension can also be quickly
  edited through a RMB menu option, gtEdit
  Name/Value.

Note a recent Generate might be necessary to
see Value as well as Name
33
Workshop 3-1, Sketching

• Using a simple example, lets see how we put to
  use what weve seen so far (note RMB Right
  Mouse Button).
• Goal
• Sketch a rectangle 50mm high and 75mm wide with
  the bottom left corner at the origin.
• Add a 10mm radius circle within the rectangle
  with the center 20mm from the left side and 30mm
  from the bottom.
• Place all dimensions where they can be easily
  viewed.

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Workshop 3-1, Sketching

• gtFilegtNew, or Start DesignModeler (Geometry)
  stand alone mode
• When prompted, set length unit to millimeters

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Workshop 3-1, Sketching
Icon

• When DM starts, switch to sketch mode using the
  sketch tab.
• Note use the Look At icon (or RMB options) to
  orient the sketch plane in the normal direction.
• Select the Rectangle tool and place the cursor
  at the origin.
• Once the P (point constraint) symbol shows,
  click, hold and drag, then release to create the
  rectangle.

RMB
Click
Drag
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Workshop 3-1, Sketching
Icon

• Before continuing, click the Fit icon (or RMB
  menu).
• Now choose the Circle tool and click, drag and
  release to create a circle in the approximate
  location within the rectangle.

RMB
37
Workshop 3-1, Sketching

• Well now formalize the sketch by adding
  dimensions.
• Select the Dimension toolbox and leave the
  default selection at General.
• Click on the top line of the rectangle to display
  the proposed dimension.
• Place the dimension above the rectangle by
  dragging and clicking.

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Workshop 3-1, Sketching

• Repeat the preceding steps to add the remaining
  dimensions.
• Next modify the details for each dimension to the
  desired values as shown.

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Workshop 3-1, Sketching

• To complete our sketch use the Move function in
  the Dimension toolbox to position (drag) the
  dimensions (like below for example).

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Workshop 3-1, Sketching

• Now try animating several dimensions
• Choose the Animate function then click on a
  dimension in the graphics window.
• Change the dimension display from Name to
  Value.

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Workshop 3-1, Sketching

• As a last check of our stated goals go to the
  details for sketch 1 and change Show
  Constraints? to gtYes.
• Scroll down to the details for Line7 and note the
  base point is coincident with the origin - - DM
  captured our design intent during sketching.
• Note leave DM session running as we will
  continue with this geometry later.

42
Sketch ModeModifying Sketches

• The Modify toolbox contains a number of functions
  for editing sketches.
• Some functions are self explanatory (e.g. fillet,
  chamfer). This section will focus on some of the
  less obvious functions.
• Remember! - check the status bar at the bottom of
  the GUI for real-time instructions for each
  function.

Status Bar - Example
43
Sketch ModeModifying Sketches

• Split
• RMB Options (choose before selecting edge)
• Split Edge at Selection (default) splits an edge
  into two pieces at the selection location (unless
  the edge is a full circle or ellipse). For a full
  circle or ellipse, both start and end endpoints
  are created at the selection location.
• Split Edges at Point Select a point, and all
  edges, which pass through the selected point, are
  split there.
• Split Edge at All Points Select an edge and it
  is split at all points that it passes through and
  that have a coincident constraint to it.
• Split Edge into n Equal Segments Set the value n
  in the edit box and then select the edge which
  you want to Split.
• Note up to 100 allowed for n.
• Split is useful for sketches to be used with
  Skin/Loft
• Split edges also offer greater control in
  subsequent meshing and/or boundary condition
  operations.

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Sketch ModeModifying Sketches

• Drag
• Can drag a point or edge using the cursor.
• How the model changes depends on what is
  selected, existing constraints and dimensions.
• Can pre-select multiple entities before issuing
  the Drag function.

Drag - Example
Select corner point of rectangle and drag.
Drag
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Sketch ModeModifying Sketches

• Cut/Copy
• Requires the selection of a paste handle (RMB)
  relative to which the Paste will be performed.
• The paste handle is the location to which the
  cursor is attached while you are moving the image
  into position to paste.
• RMB paste handle options
• End / Set Paste Handle, and specify the paste
  handle.
• End / Use Plane Origin as Handle, the 0.0, 0.0
  location of the plane will be used as the paste
  handle
• End / Use Default Paste Handle, the start of the
  first curve selected will be used as the handle
• This lets you select a set of items to copy to an
  internal clipboard, and leaves the originals in
  the sketch.
• If Cut or Copy is exited without selecting a
  paste handle, a default will be used.

Copy RMB options.
46
Sketch ModeModifying Sketches

• Paste
• RMB Context Menu
• Rotate by /- r Degrees
• Flip Horizontally / Vertically
• Scale by Factor f or 1/f
• Paste at Plane Origin
• Change Paste Handle
• End
• Paste lets you take items placed on the clipboard
  by Cut or Copy and place them into the current
  (or new) sketch, even if it is on a different
  plane.

47
Sketch ModeModifying Sketches

• A Copy/Paste example . . .
• After creating a rectangle we wish to copy it,
  rotate it by 45 degrees with respect to the
  origin and scale it by a factor of 0.5.

1. RMB

1. Copy

1. Select edges

48
Sketch ModeModifying Sketches

1. RMB Rotate

1. RMB Scale

1. Choose Paste and set options

1. RMB Paste

1. RMB End

• Notes on Copy/Cut/Paste
• After copying, paste can be done multiple times.
• Can copy from one sketch and paste to another.
• During Paste operation you can change the paste
  handle.

49
Sketch ModeModifying Sketches Quick
Cut/Copy/Paste

• Cut, Copy, and Paste commands are available as
  RMB options in sketching mode.

1) Select source edges 2) RMBgtCopy 3) Select
paste origin 4) Paste the edges
50
Sketch ModeModifying Sketches

• Replicate
• The Replicate command is equivalent to the Copy
  command, followed by a Paste.
• After one of the End / options is selected, the
  right mouse button changes to the Paste right
  mouse button.
• Move
• The Move command functions the same as the
  Replicate command with the exception that your
  original selection is moved to a new location
  instead of being copied.

51
Sketch ModeModifying Sketches

• Offset
• The Offset function allows you to create a set of
  lines and arcs that are offset by an equal
  distance from an existing set of lines and arcs.
• The original set of lines and arcs must be
  connected in an open or closed profile.
• Preselect or select the edges then choose the
  right mouse button option End selection / Place
  offset
• The cursor location is used to determine three
  things
• Offset distance
• Offset side
• Offset area
• Distance and Side are clear but the area is
  very important
• If portions of your selected curves would
  collapse out or cross over one another given the
  current offset side and distance, the cursor
  location determines which area of offset curves
  is kept.
• An example . . .

52
Sketch ModeModifying Sketches
First we choose all edges to be offset
The direction and distance the cursor is moved
determines the offset.
53
Sketch ModeModifying Sketches
Notice as the offset is dragged further, the arc
will eventually intersect the bottom line.
By alternating the cursor location (left and
right) we can determine which offset region will
be retained.
54
Sketch ModeSketch Instance

• Sketch Instancing allows copies of sketches to be
  added in other planes. The copies are
  persistent, meaning they will update when the
  source sketch is updated.
• Features
• Edges in a sketch instance are fixed (like a
  plane boundary) and cannot be moved, edited, or
  deleted by sketch operations
• When changes are made in the base sketch its
  instances will be updated when a Generate is done
• A sketch instance can be used just like normal
  sketches for creating other features except
• Cannot be used as base sketches for other
  Instances
• Sketch instances are not included in the
  pull-down list of sketches

Step 1 Choose the destination plane for the
instance. The source sketch must be in a plane
prior to the destination plane (higher in
Tree). Therefore, you can never place a sketch
instance onto the XYPlane.
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Sketch ModeSketch Instance
Step 2 Choose the source sketch via Apply/Cancel
buttons. Step 3 Modify the placement options.
The sketch instance may be offset, rotated, and
scaled. Step 4 Click Generate to complete the
sketch instance.
56
Sketch ModeSketch Instance

• Example Sketch2 is instanced onto Plane4 as
  Sketch5. Note how the instance appears as fixed
  edges, similar to plane boundary edges.

57
GeometryGeometry Interfaces

• DM gtFilegtImport gtFilegtAttach capability
• Can Import/Attach anytime, even multiple times
  per model
• Can add, subtract, etc. during Import/Attach
  process
• Base Plane Property for orientation
• The following CAD versions are supported

• ACIS - 13.0
• BladeGen 4.1 (DM-CFX Course)
• Parasolid - 16
• SolidWorks - 2003 SP4 / 2004
• Solid Edge - V15 / V16
• Mechanical Desktop 2004DX /2005
• Autodesk Inventor R8 / R9

• Unigraphics NX 2.0 / NX 1.0
• CATIA - V4
• CATIA - V5 (R2 - R13)
• Pro/ENGINEER 2001 / Wildfire 1 2
• IGES Reader - 4.0, 5.2, 5.3

58
GeometryAttaching to a CAD Session

• If a CAD session is currently open, this
  automatically imports the model into the
  DesignModeler session
• FilegtAttach to Active CAD File
• Maintains bi-directional associativity

59
GeometryImporting CAD Files

• FilegtImport External Geometry File
• The active plane controls placement for
  assembly modeling (multi-bodies).
• The details pane import type Add, Cut, Slice,
  etc
• Does not maintain associativity

Active Plane
Add
Cut
60
GeometryPositioning Imports

• Both Import and Attach have a Base Plane
  property.
• Specify the plane (orientation) in which the
  Import or Attach model is referenced
• When creating a new Import or Attach feature, the
  active plane is chosen as the Base Plane by
  default
• Users select planes from the tree view or Plane
  pull-down list prior to import
• Example
• XY chosen for first import
• YZ plane for second import
• Add material option chosen

61
GeometryImport Units

• Set the desired length unit when DM starts
• Some import types allow you to set the units via
  the import details (Prior to Generate)
• DM then converts the model length units into the
  current unit system

62
GeometryExporting a Model

• FilegtExport
• IGES exporting
• When exporting the model to an IGES file, you
  have the option to export solids or just trimmed
  surfaces.
• gtToolsgtOptions

63
GeometryBody Attributes

• DM supports two kinds of body attributes through
  Import and Attach features
• Surface body thickness
• Material properties
• Material properties are controlled by the Import
  Material Properties option in the property list
  for Import and Attach features. If set to gtYes,
  then any material properties will be processed
  with the bodies. Material properties are
  read-only in DM they are brought in through the
  Import and Attach features, but you cannot edit
  them.
• Properties are transferred with the model when
  sent to Sim.

64
GeometryBody Attributes

• Surface body thickness is transferred to DM from
  CAD systems that support it.
• Users can modify the thickness of any surface
  body in DM.
• The thickness will be attached to the surface
  bodies when the model is sent to Sim.

65
Workshop 3-2, 3D Geometry

• Goals
• Utilize the model created in Workshop 3-1 and
  generate 3D geometry from the sketch.
• Create a new sketch and extrude it to create a
  boss on the original model.
• Create another sketch and Imprint a face on the
  boss to allow for applying boundary conditions to
  an FE model.
• Save the model and Exit.
• Start Page (if workshop 3-1 was closed)
• Choose the option Open

66
Workshop 3-2, 3D Geometry

• Continue with the database created in Workshop
  3-1
• If this is not available open the file called
  Workshop 3-1.agdb and continue with workshop
  3-2.
• With the model open choose the Extrude icon
  from the toolbar.
• In the extrusion details change the depth to
  10mm.
• Generate the extrusion.

67
Workshop 3-2, 3D Geometry

• Insure that the XYPlane is active and click on
  the New Plane icon.
• In the Details of Plane4 set Transform 1 to be
  Offset Z and change the offset Value to 50mm.
• Generate the Plane.

68
Workshop 3-2, 3D Geometry

• Click the Look At icon to reorient the view.
• Switch to Sketching mode and choose Rectangle
  from the drawing toolbox (check Auto-Fillet box).
• Sketching gtDrawgtRectangle
• Draw a rectangle and utilize Auto-Fillet
  approximately as shown here.
• Click on the Dimensions toolbox.
• Sketching gtDimension

69
Workshop 3-2, 3D Geometry

1. Dimension the sketch as shown below. Note
   your dimension names may not match those shown.

70
Workshop 3-2, 3D Geometry

• From the toolbar choose Extrude (do not
  generate yet!).
• An isometric view shows the proposed (wireframe)
  extrude using a surface-normal direction (facing
  away from the original model).
• From the Detail window change the direction field
  from Normal to Reversed.
• Change the Type to To Next
• Generate the extrusion.

71
Workshop 3-2, 3D Geometry
The extrude operation creates the boss which is
merged with the original geometry.
Click on gtDisplay Plane button to turn off
plane dimensions if necessary
72
Workshop 3-2, 3D Geometry
In our FE simulation we wish to add a boundary
condition at an arbitrary location on the boss.
We will imprint a face on the boss for that
purpose.

1. Select (Highlight) the top surface of the boss.
2. Click the New Plane icon in the toolbar.
3. Generate the plane.

73
Workshop 3-2, 3D Geometry

• Click the Look At icon from the toolbar.
• Go to sketch mode and choose circle from the draw
  toolbox.
• Sketching gtDrawgtCircle
• Draw a circle approximately like the one shown
  here.

74
Workshop 3-2, 3D Geometry

• Add dimensions as shown at right. Note your
  dimension names may not match those shown here.
• Sketching gtDimensionsgtGeneral

75
Workshop 3-2, 3D Geometry

• Choose Extrude from the toolbar (do not
  Generate).
• In the details change the operation to Imprint
  Faces.
• Generate the extrusion

76
Workshop 3-2, 3D Geometry
Make sure the surface selection filter is active
and highlight (select) the circular surface on
the boss. (Rotate the Model as Desired) Notice
we now have a circular area that we can use for
localized boundary conditions in our simulation.
Exit without saving FilegtExit Workbench