Introduction

Geometry and mesh object creation is accessed within the Input dialog’s Geometry and Mesh tabs, respectively. To create a new geometry or mesh object, the A/O/M Action must first be set to Create, and then the desired Object type (e.g. Box, Mesh) and creation Method (e.g. Local, Auto) may be specified. To import existing CAD geometry or meshes, consult the Importing Model Inputs section.

General Methodology

Object creation requires (1) the specification of data in one or more Input dialog fields, and/or (2) left-clicking on one or more objects/locations in the Model View, and/or (3) clicking of the Accept button or pressing the Enter key.

It is also important to remember that, when input from the Model View is not required (e.g. Locate method), StressCheck will invoke the C/A/O/M object creation sequence when you click the left mouse button while the Create cursor  is in the Model View. For example, setting the C/A/O/M to Geometry class > Create > Point > Locate, and clicking the left mouse button in the Model View display area will result in the creation of a new point.

Object creation use cases involving the combinations of (1), (2) and (3) above will be explored in the following. In the special case of the Point or Intersection methods, clicking the Accept button without interacting with the Model View will result in a dialog prompting the user if they want to create an object at every point or intersection, respectively.

For more information on object creation refer to the Model Inputs sections, specifically the Geometry Overview and Meshing Overview. For details on the object creation method requirements, refer to Primitive Geometry Creation Methods and Node Creation Methods.

Screen/Input Toggle

By default, the Screen: option is enabled for Input dialog fields. Screen: means the fields will be disabled for manual input and will continuously obtain data from the location/movement of the mouse cursor in the Model View. For example, the dialog shown in Figure 1 will be observed when using Create > Point > Locate:

In this way, it is not required to enable and specify the X, Y, Z input fields if the user desires to let StressCheck determine the X, Y, Z coordinates of the point based on the mouse cursor click location. Any Input dialog field may be enabled for manual input by checking the box to the left of the field.

All Input dialog fields may be enabled for manual input (Input:) by checking the checkbox next to the Screen/Input toggle. For Create > Point > Locate, the dialog shown in Figure 2 is observed:

In this way, the user has control of the values/parameters/formulae entered in each Input dialog field, and these values will not be updated when the mouse cursor is in the Model View.

Note: the Screen: option, while not typically used to Create, is beneficial when Editing existing objects (Action: Edit), as a selected object’s properties will be extracted and returned for all disabled Input dialog fields; any enabled Input dialog fields will retain their current inputs, facilitating object modification as well as retention of input data for new object creation. Consult the Object Query/Modification Overview section for details.

Use Case #1: Creating a Solid Box at a Global Location

In some object creation cases, the user is required to specify data in the Input dialog fields and then click the Accept button. For example, to create a solid Box at a Global location (i.e. Create > Box > Locate), the user simply inputs the Global location of the base of the box (X, Y, Z), along with the box dimensions (Width, Height and Depth) and orientation with respect to the Global system (Rot-X, Rot-Y and Rot-Z), and clicks the Accept button (Figure 3):

As no additional input is required, clicking the Accept button (or pressing Enter or left clicking on the screen) will result in the creation of the Box and its display in the Model View (Figure 4):

Note: to create a box comprised of trimmed surfaces, you may toggle the Solid button to Surface (Figure 5):

Use Case #2: Creating a Surface Cylinder at a Local System

In some object creation cases, the user is required to specify data in the Input dialog fields and then left click in the Model View to select an object. For example, to create a surface Cylinder attached to a Local system (i.e. Create > Cylinder > Local), the user simply switches from Solid to Surface, inputs the cylinder dimensions (Radius and Height) and then left clicks in the Model View on an existing Local System (Figure 6):

Using the settings shown above, left clicking on the System object will result in the creation of the surface cylinder shown in Figure 7 in the same location/orientation of the selected system:

If multiple local systems are available, the creation option can be repeated using the same inputs by continuing left clicking on each local system.

Note: for primitive surface objects, the P1 and P2 fields control the parameter limits of the surface. For example, for a surface cylinder the range for P1 is [0,360] and the range for P2 is [0,1].

Use Case #3: Creating a Blended Edge using the Rolling Ball Method

In some object creation cases, the user is required to specify data in the Input dialog fields, select one or more objects from the screen and click the Accept button. For example, to create a blended edge at several surface intersections using the Rolling Ball method (i.e. Create > Blend Edge > Rolling Ball) as shown in Figure 8, the user simply inputs the rolling ball radius (Radius), left clicks in the Model View on one or more curves representing the surface intersections to be blended, and clicks the Accept button (Figure 9):

Note that holding the Shift key is not required during the selection of the curves and that the Ctrl key can be used to deselect a single object.

Use Case #4: Creating a New Body using Boolean-Subtract

In some object creation cases, the user is required to select one or more objects from the screen and click the Accept button. For example, to create a new body by subtracting a solid cylinder from a solid box (i.e. Create > Body > Bool-Subtract), the user simply left clicks in the Model View on the target body (box, green wireframe) and then the tool body (cylinder, red wireframe), and clicks the Accept button (Figure 10):

Clicking Accept will result in the creation of the new body as shown in Figure 11:

Note: when the Action combo-box is set to Create, using the Shift key is not necessary to select multiple objects during object creation. After the target body is selected to select multiple tool bodies, simply continue left clicking. To de-select one or more tool bodies, hold down the Ctrl key while left-clicking. For more details on 3D Boolean operations, as well as target/tool selection, consult 3D Solid Body Operations.

Use Case #5: Creating a New Body using a Clipping Plane

In some object creation cases, the user is required to select one or more objects from the Model View and the new object will be created automatically on the final left click selection. For example, as shown in Figure 12, to create a new body by clipping solid material in the positive normal to a plane (i.e. Create > Body > Clip-Front), the user simply left clicks in the Model View on the target body (box, green wireframe) and then the clipping object (plane, not yet selected):

Left clicking on the plane will result in the creation of the new body as shown in Figure 13:

Note: The small green system shown in Figure 12 and Figure 13 is used for determining the plane’s positive normal direction.