Creating a New Geometry
After selecting Geometry Tools in the drop down list of the Geometry workspace window, click Create to prompt a drop-down menu to appear. This menu includes the following modeling operations:
- Extrude from Face
- Revolve from Face
- Sheet Body
- Sheet Body From Faces
- Wire Body
- Equation based
The Create New menu items are displayed in the following figure:
Additionally, these tools are accessible from the Project Tree by right-clicking the Part branch, as seen in the following figure:
Selecting any of these operations will prompt a similar series of editing tools.
Specify Orientation Tab
The Specify Orientation tab provides tools for orienting geometric parts in the simulation space. For a detailed discussion of this tab, refer to Orienting Objects in the Simulation Space.
Edit Cross Section
In the Edit Cross Section tab, four toggle buttons including Shapes, Constraints, Tools, and Snapping. Each have a corresponding series of buttons in its own toolbar below. Clicking these labeled buttons will toggle the corresponding toolbars on and off. All of these buttons, in addition to the View Tools detailed earlier, are also available in the drop-down menus in the upper-left part of the screen. Additionally, a button labeled Construction Grid is available to edit the spacing of the visible grid lines in the 2-D sketcher. (This has no impact on the FDTD grid definition).
The current object is named in the box labeled Name in the upper right section of the Edit Cross Section tab. If a name is not defined in this box, the object is assigned a default name in the Project Tree when it is added to the project. The object can be renamed at any time in the Project Tree by right-clicking the object and selecting Rename.
To the right of the Name dialog box are two buttons, Undo and Redo. Clicking the Undo button will undo all actions carried out in the Edit Cross Section tab. Similarly, the Redo button will repeat any actions mistakenly erased during an undo operation.
The Edit Cross Section tab contains a number of Shapes sketching tools that are useful for creating simple 2-D geometries for wire bodies and sheet bodies. They also serve as a common starting point to define 2-D cross sections for 3-D bodies such as extrusions, revolutions, and more complicated solid modeling operations. The Shapes tools are selected by clicking their respective icon.
- Pressing Esc or Backspace will back-up one step when using a multi-step creation tool.
- Pressing Esc a second time will deactivate the edge creation tool and activate the default Select tool.
- Pressing Tab will bring up a dialog to specify the position.
The following is a list of the 2-D shapes available in EMPro:
- Straight Edge
- Polyline Edge
- Perpendicular Edge
- Tangent Line
- N-Sided Polygon
- 3-Point Arc
- Arc Center, 2 Points
- 2-Point Arc
- Circle Center, Radius
- 3-Point Circle
- 2-Point Circle
For a detailed description of each shape tool, refer to Shapes.
The Tools buttons provide useful functionality to users while sketching in the 2-D sketcher.
- Trim Curves
- Insert Vertex
- Fillet Vertex
For a detailed description of each 2-D sketcher tool, refer to Tools.
Constraints are restrictions placed on geometric parts that must be satisfied in order to consider the model valid. They ensure that the user's intent is sustained throughout a calculation when parameters may change. Some objects are created with constraints already embedded. For instance, a rectangle is composed of four straight edges that are constrained perpendicularly as seen in preceding illustration. Other constraints are user-defined by means of Constraint tools.
Applying a constraint to an object will often affect other characteristics of the object. For instance, applying a horizontal constraint to one side of an irregular quadrilateral will most likely change the length of one or more sides and the angles that form with those connecting sides. Thus, it is important to lock any points that are intended to stay static. There are two main ways to do this:
- By selecting the Lock Constraint tool and clicking the the appropriate vertex or side.
- By selecting the Select/Manipulate tool, right-clicking the appropriate vertex or side, and selecting Lock Position, as shown below.
Locking or editing a vertex's position with the Select/Manipulate tool
For more about the Select/Manipulate tool's functionality, refer to Select/Manipulate.
Each type of the following types of Constraint tools has its own green symbol or letter that is visible when the mouse is held over the constrained segment.
- Equal Length
- Equal Distance
- Equal Radius
For a detailed description of each constraint, refer to Constraints.
Snapping tools are available to facilitate the exact placement of vertices on the sketching plane. When snapping is enabled, the mouse will be snapped to the closest of one or more snapping landmarks if one comes within range. For example, if Snap To Grid Lines is selected, the mouse is moved or snapped to points on the closest grid line as it is moved around in the sketching plane. This makes it much easier to place a vertex in the desired position without having to zoom in to a discrete position. Blue dots and blue lines represent the snapped location of the mouse when snapping is enabled.
In the case that the mouse is not within sufficient range of a selected landmark listed below, a vertex will be placed at its exact location on the sketching plane as if snapping were not turned on. (For example, if the mouse is dragged to the middle of a cell and the Snap To Grid Lines option is selected, the vertex will be placed in the center of the cell because it is not close enough to a surrounding grid line.)
Several snapping options can be selected at a time, in which case, the vertex will be snapped to the closest landmark that is within range of the mouse.
- Snap To Grid Lines
- Snap To Grid/Edge Intersections
- Snap To Vertices
- Snap To Edges
- Snap To Edge/Edge Intersections
For a detailed description and image of each, refer to Snapping.
Customizing the Construction Grid
The Construction Grid drop-down controls the appearance of the grid without impacting its actual cell size.
- Automatically Adjust Line Spacing causes the construction grid to adjust its line spacing with the current zoom level. As you zoom in, the lines are moved to be closer to each other. As you zoom out, they decimate and become further apart.
- Line Spacing is available when automatic isn't checked. This is the spacing between adjacent lines of the construction grid.
- Highlight Interval controls the interval which lines are highlighted. Every "Nth" line will be made bold.
- Mouse Spacing controls the minimum resolvable distance by the mouse. As you move the mouse, you will be unable to move between two points closer than this specified distance.
Editing the Construction Grid
3-D Operation Tabs
If subsequent tabs are available to the right of the Edit Cross Section tab, continue on to complete a 3-D operation. (These tabs are not available for 2-D objects.)
The figure below shows the Advanced drop-down menu inside of the Extrude tab, available when an Extrude operation is selected. This menu contains operations that can be applied to the 3-D object. For more information on these operations, refer to Advanced 3-D Solid Modeling Operations in the "Appendix of Geometric Modeling".
Primitive Building Blocks
EMPro has a built-in library of parameterized 3D objects that includes the following types of shapes: Bondwire, Box, Sphere, Torus, Prism, Pyramid, Frustum, Helix, Solder Ball, and Equation Based. A shape can be inserted by selecting the appropriate item from the Create New menu. With each of these shapes corresponds an editing tool, that lets you specify the shape's parameters, see folowing figure. By double clicking on the building block in the Part node of the Project Tree, one can (re)edit the parameters after insertion. The editing boxes are all parameterizable, i.e., use of EMPro parameters, see for example parameter P1 in the figure below. The object can be positioned after insertion by using the Specify Orientation menu.
Equation Based Sheet Objects
Select Equation Based ... from the Create New menu to insert an equation. There are a number of presets available in EMPro, which can be loaded using the << button. Users can add presets to EMPro which will also be available for other projects, i.e., presets are application (EMPro) specific and not project specific. Hereto the user must specify the X-, Y-, and Z- parameters and save the preset using the >> button. Note: these parameters may contain refrences to U and V, and/or mathematical functions/operators such as: +, -, *, /, mod, abs, ceil, floor, pi, e, exp, log, ln, sqrt, arccos, arccosh, arcsin, arcsinh, arctan, arctanh, arccot, arccoth, arcsec, arcsech, arccsc, arccsch, cos, cosh, sin, sinh, tan, tanh, cot, coth, sec, sech, csc, csch. User defined presets can be removed from the list, EMPro defined presets cannot be deleted.
Modifying Existing Geometry
The Modify button in the Geometry workspace window may be selected to modify the geometry of existing objects in the project.
- Specify Orientation
- Chamfer Edges
- Blend Edges
- Shell Faces
- Loft Faces
- Remove Faces
- Offset Faces
For images of each of these operations, refer to Modifying Existing Geometry.
The following boolean operations are available in EMPro:
- Two Parts
The Two Parts tool provides several boolean operations to subtract, intersect, or unite two objects. For these operations, one object must be selected to be the Blank, and the other the Tool which acts on the blank.
Holes may also be extruded or revolved through any part with its respective tool in this menu. An object is selected in the Pick Blank tab and the cross section of the hole is sketched and oriented in the Edit Profile and Feature Orientation tabs, as described in the Edit_Cross_Section_Tab and Specify_Orientation_Tab, sections respectively. Then the shape of the removed section is specified in the Extrude Boolean tab, or Revolve tab depending on which operation is selected. The Preview tab shows a preview of the object before the changes are formally applied to the project. For more information on defining extrusions or revolutions, refer to 3-D Solid Modeling Options in the Appendix of Geometric Modeling. An image of each boolean operation is available in Boolean Operations in the "Appendix of Geometric Modeling".
Patterns are created in EMPro by replicating a single selected object multiple times in one of the organized arrangements listed below.
For the definitions and images associated with these patterns, refer to 3-D Patterns.