Creating Surfaces

Wireframe and Surface allows you to model both simple and complex surfaces using techniques such as extruding, lofting and sweeping. Two creation modes are available: either you create geometry with its history or not. Geometry with no history is called a datum. For creating datum feature use create datum icon in tool menu icon.

4.13.1 Creating Extruded Surfaces

This task shows how to create a surface by extruding a profile along a given direction. Click the Extrude icon . The Extruded Surface Definition dialog box appears. Select the profile to be extruded and specify the desired extrusion direction. Enter numerical values or use the graphic manipulators to define the start and end limits of the extrusion. You can click the Reverse Direction button to display the extrusion on the other side of the selected profile. Click OK to create the surface.

4.13.2 Creating Revolution Surfaces

This task shows how to create a surface by revolving a planar profile about an axis. Click the Revolve icon . The Revolution Surface Definition dialog box appears. Select the Profile and a line indicating the desired Revolution axis. Enter angle values or use the graphic manipulators to define the angular limits of the revolution surface. Click OK to create the surface. There must be no intersection between the axis and the profile. If the profile is a sketch containing an axis, the latter is selected by default as the revolution axis. You can select another revolution axis simply by selecting a new line.

4.13.3 Creating Spherical Surfaces

This task shows how to create surfaces in the shape of a sphere. The spherical surface is based on a center point, an axis-system defining the meridian & parallel curves orientation, and angular limits.

Click the Sphere icon from the Extrude-Revolution toolbar. The Sphere Surface Definition

dialog box is displayed. Select the center point of the sphere. Click Apply to preview the surface.

Modify the Sphere radius and the Angular Limits as required. Click OK to create the surface.

4.13.4 Creating Offset Surfaces

This task shows how to create a surface by offsetting an existing surface. Click the Offset icon . The Offset Surface Definition dialog box appears. Select the surface to be offset. Specify the offset by entering a value or using the graphic manipulator. An arrow indicates the proposed direction for the offset. The offset surface is displayed normal to the reference surface. Click Apply to previews the offset surface. Check the Both sides button to generate two offset surfaces, one on each side of the reference surface. Click OK to create the surfaces.

4.13.5 Creating Swept Surfaces

a) Using an Explicit Profile

This task shows how to create a swept surface that uses an explicit profile. You can create a swept surface by sweeping out a profile in planes normal to a spine curve while taking other user-defined parameters (such as guide curves and reference elements) into account. You can sweep an explicit profile: along one or two guide curves (in this case the first guide curve is used as the spine), along

one or two guide curves while respecting a spine. The profile is swept out in planes normal to the spine.

This task shows how to create swept surfaces that use an explicit profile. Click the Sweep icon . The Swept Surface Definition dialog box appears. Click the Explicit profile icon. Select the planar Profile to be swept out. Select a Guide curve. If needed, select a Spine. If no spine is selected, the guide curve is implicitly used as the spine. You can define relimiters (points or planes) in order to longitudinally reduce the domain of the sweep, if the swept surface is longer than necessary for example. If needed, select a Second Guide. If you want to control the position of the profile during the sweep, you can select a reference Surface.

In the Smooth sweeping section, you can check: the Angular correction option to smooth the sweeping motion along the reference surface. Click OK to create the swept surface.

b) Using a Linear Profile

This command is only available with the Generative Shape Design product. This task shows how to create swept surfaces that use an implicit linear profile. Click the Sweep icon . The Swept Surface Definition dialog box appears. Click the Line profile icon. The five possible cases are Two limits, Limit and middle, With reference surface, With reference curve, With tangency surface, With draft direction. Click the Law button if you want a specific law to be applied rather that the absolute value. Click OK to create the swept surface. The surface (identified as Sweep.xxx) is added to the specification tree.

c) Using a Circular Profile

This command is only available with the Generative Shape Design product. This task shows how to create swept surfaces that use an implicit circular profile. Click the Sweep icon . The Swept Surface Definition dialog box appears. Click the Circle icon, then use the combo to choose the subtype.

The two following cases are possible using guide curves: Select three guide curves, Select two guide curves and enter a Radius value. You can then choose between four possible solutions by clicking the Other Solution button.

The two following cases are possible using a center curve: Select a Center Curve and a Reference angle curve, Select a Center Curve and enter a Radius value.

The two following cases are possible using a reference surface to which the swept surface is to be tangent: Select two guide curves, and a reference surface to which the sweep is to be tangent.

Select guide curves, a reference surface to which the sweep is to be tangent, and enter a radius value.

Click OK to create the swept surface. The surface (identified as Sweep.xxx) is added to the specification tree.

d) Using a Conical Profile

This command is only available with the Generative Shape Design product. This task shows how to create swept surfaces that use an implicit conical profile, such as parabolas, hyperbolas or ellipses. Click the Sweep icon . The Swept Surface Definition dialog box appears. Click the Conic icon, and then use the combo to choose the subtype. Two guides, Three guides, Four guides, Five guides. Click OK to create the swept surface. The surface (identified as Sweep.xxx) is added to the specification tree.

4.13.6 Creating Filling Surfaces

This task shows how to create fill surfaces between a number of boundary segments. Click the Fill icon . The Fill Surface Definition dialog box appears. Select curves or surface edges to form a closed boundary. You can edit the boundary by first selecting an element in the dialog box list then choosing a button to either. Add a new element after or before the selected one, Remove the selected element, Replace the selected element by another curve. Select a passing point. This point should lie within the area delimited by the selected curves. If not, the results may be inconsistent.

Click OK to create the fill surface.

4.13.7 Creating Lofted Surfaces

You can generate a lofted surface by sweeping one or two planar section curves along a computed or user-defined spine. The surface can be made to respect one or more guide curves. Click the Loft icon . The Lofted Surface Definition dialog box appears. Select one or two section curves. If

needed, select one or more guide curves. In the Spine tab page, select the Spine check box to use an automatically computed spine or select a curve to impose that curve as the spine. The Relimitation tab lets you specify the loft relimitation type. You can choose to limit the loft only on the Start section, only on the End section, on both, or on none. Use the Planar surface detection check button to automatically convert planar surfaces into planes. Several coupling types are available, depending on the section configuration: Ratio, Tangency,

Tangency then curvature, Vertices. Click OK to create the lofted surface.

4.13.8 Creating Blended Surfaces

This task shows how to create a blended surface, that is a surface between two wireframe elements, taking a number of constraints into account, such as tension, continuity, and so forth.

Click the Blend icon . The Blend Definition dialog box appears. Successively select the first curve and its support, then the second curve and its support. Set the continuity type using the Basic tab. Activate the Trim first/second support option to trim them by the curve and assemble them to the blend surface. You can also specify whether and where the blend boundaries must be tangent to the supports boundaries: Both extremities, None, Start extremity, End extremity. Set the tension type using the Tension tab. It defines the tension of the blend at its limits. Click OK. The surface (identified as Blend.xxx) is added to the specification tree.