What is Subdivision Modelling?
Subdivision modelling is often likened to clay modelling in the real world, where you push and pull or ‘sculpt’ a block of material with a simple set of tools.
It’s also referred to as ‘Sub-D’ modelling, but where does ‘subdivision’ or ‘Sub-D’ come from?
Well, ‘subdividing’ is the act of dividing a polygonal mesh into smaller, more detailed regions.
Subdivision surfaces are further broken into faces by intersecting ‘edge loops’ which follow the surface form.
Changes can be made to these faces, edges, and vertices by pushing, pulling, scaling, rotating, and shaping with features.
Compared to a parametric design tool such as SOLIDWORKS, subdivision modelling is a more fluid design method and enables you to closely replicate organic shapes and ergonomic designs in less time than other modelling methods.
Why Use Subdivision Modelling?
Subdivision modelling allows users to create organic and freeform shapes and offers precision control and flexibility when working with rapidly changing or user-centric designs.
Commonly, ergonomic aspects of products such as handles would be guided by a user-centric design approach, allowing studies and feedback to influence design changes.
Subdivision modelling gives the flexibility required to adapt more quickly to these design changes and make necessary adjustments. The creation of smooth, organic shapes becomes easy with 3D Sculptor where the same shapes may be time consuming and difficult to create with parametric techniques.
Getting Started with 3D Sculptor
As you grow more experienced, you’ll develop your own workflow and processes. To get started with subdivision modelling, the following basic workflow applies:
- Start a new component
- Add primitives
- Select geometry
- Manipulate geometry
After logging into your 3DEXPERIENCE platform, access the Compass in the top left corner and locate the 3D Sculptor role.
Clicking the role reveals the subdivision modelling tools.
Click on the xShape application to open the app and start subdivision modelling.
HOW TO CREATE A NEW MODEL IN XSHAPE
New components can be created from the xShape welcome screen.
As with any design application in the 3DEXPERIENCE platform, the model file is referred to as a physical product.
Components can be created at any stage via the New Component button in the toolbar when a model is open.
After creating a new model, primitives can be added and sculpting can begin.
WHAT ARE PRIMITIVES?
Primitives are the foundation for any new component or body in xShape.
They are basic 3D or 2D shapes from which a component can be sculpted. Choose a primitive which looks like the final geometry you will be creating to ensure that you have the best starting point.
The following are 3D primitives that can be inserted into components within xShape.
- Box
- Quadball
- Cylinder
- Globe
- Taurus
- Cone
- Pyramid
2D primitives that can be inserted are planes in the shape of rings, rectangles, and discs.
HOW TO ADD A PRIMITIVE
After creating a new xShape component, select the subdivision tab in the toolbar to begin.
Use the 2D or 3D primitive buttons and select a primitive from the dropdown. Clicking on a primitive will start a new primitive and snap it to your cursor for you to position.
When adding a primitive, consider its placement. To place the primitive at the origin, look for the ‘X’ and click the left mouse button to place the primitive.
Once placed, use the on-screen flags to control the number of edge loops for each major face and the scaling for the primitive.
It’s usually best to start with fewer edge loops to begin with, as you can always add more as you go.
Use the ‘Scale by Bounding Box’ option to control the size of your component using dimensions, rather than just percentages.
HOW TO SELECT GEOMETRY
Once you’ve added a primitive into xShape, the faces, edges, and vertices can all be selected and manipulated.
Use the selection filter button on the heads-up toolbar at the top of the screen to change which entities can be selected. This is a useful tool that you will use a lot!
By default, if a box select is used, non-visible entities through the model will also be selected.
If necessary, this can be toggle off by selecting the button above.
The best way to select geometry in xShape is using a box select.
It is recommended to orientate the model normal to your screen, so that you can clearly see which entities have been selected. Use the view selector in the top right corner to orientate the screen.
HOW TO MANIPULATE GEOMETRY
Once selected, edges, faces and vertices can all be manipulated using a tool called the robot.
The robot will allow you to push, pull, scale, or rotate the selected geometry.
The robot has 5 types of handles:
- Axis handles – Used to push or pull in axial directions.
- Plane handles (areas located between axis handles) – Used to move geometry in planar directions.
- Arc handles – Used to rotate.
- Scale handles (marked as a dot at the end of each axis handle) – Used to scale the selected geometry in one, two or three directions.
- Centre handle – used to control the orientation and position of the robot.
NOTE: The orientation of the robot is important, depending on selections, the orientation may change.
To modify the orientation of the robot, right click on the centre of the robot.
Once a selection has been made, left click and drag on a robot handle to begin manipulating geometry.
Note that in the example above, the robot appears differently since the view is normal to the screen.
Looking for More Tips?
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Don’t forget, with a SOLIDWORKS subscription, you can contact our expert Technical Support team to help you out with new commands and modelling tips.
Call us on 01926 333 777 or drop an email to support@solidsolutions.ie and one of our certified SOLIDWORKS Engineers will be in contact.