Curves GordonSurface
|
Menu location |
---|
Surfaces → Gordon surface |
Workbenches |
Curves |
Default shortcut |
None |
Introduced in version |
- |
See also |
None |
Description
The Curves GordonSurface creates a surface that skins a network of curves. This tool is part of the external workbench called Curves.
Usage
- A Gordon surface requires a network of lines or curves that create a support network for the surface.
- The surface will be "tented" between and over these lines.
- In the example above the blue lines (or ribs) represent the shape of the surface at different points along surface.
- These can be thought of as cross sections along the surface. Or, like supports that the surface will "tent" over.
- The yellow lines represent the extent and shape of the surface between the cross sections ("ribs") defined by the blue lines.
- These lines (blue & yellow) can be created in sketches.
- The sketches containing the blue ribs would typically have a placement offset.
- Each "rib" is in a separate sketch.
- The sketches containing the extent/shape (yellow) lines will typically reference external geometry from the "rib" sketches for accurate positioning.
- The sketches containing the blue ribs would typically have a placement offset.
- These need to be created before the next step.
- Switch to the
Curves workbench (install from
Addon Manager is necessary, if not previously installed)
- Now select all the lines of that will define the surface.
- The order of selection defines the stitching or tenting order.
- Use multi-select to select all lines defining the surface. (Left click while holding the Ctrl key.)
- Select the ribs first, in order. (In the example above, select the blue lines from left to right. or right to left.)
- Continue to hold the Ctrl key and select the extent lines. (Yellow lines in the example above.)
- To invoke the command, do one of the following:
Properties
- DataPlacement: Can be used to adjust the placement of the resulting Gordon surface. See: Placement
- Note: The Placement properties do not adjust the placement of the curves/lines used to create the surface, only the surface.
- DataLabel: User specified label (name) for the surface. (Default: Gordon)
- DataOutput: Defines the output type. (Default: Surface, Options: Surface, Wireframe)
- DataGordon>Max Ctrl Pts: (Default: 80)
- DataGordon>Sources: User selected lines that are used to create the Gordon surface.
- DataGordon>Tol3D: 3D tolerance (Default: 0.01)
- DataWireframe>Samples U: Number of samples in the U direction. (Default: 16)
- This value is used to determine density of the mesh when the Output property is set to Wireframe.
- DataWireframe>Samples V: Number of samples in the V direction. (Default: 16)
- This value is used to determine density of the mesh when the Output property is set to Wireframe.
- Gordon surface in wire frame mode, U=16, V=16
Notes
- The curves of each group (ribs and rails) should touch all curves of the other group.
- In other words, they must form a grid or net pattern as shown here:
- In general, the surface normal of the resulting Gordon surface will be determined by the direction of the ribs.
In this example, the surface on the left, the rails were drawn from +Y to -Y and the resulting surface normal is +Z
On the right, the ribs are drawn from -Y to +Y, resulting in the surface normal oriented -Z.
- Part Extrude can be used to create a solid from the surface.
- PartDesign Pad can also create a solid from the surface. Dragging the surface into a Body creates a Base Feature that can then be padded.
Limitations
TODO
Scripting
- Curves IsoCurve, Curves JoinCurve, Curves ParametricComb, Curves ParametricSolid, .................
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