Adaptive geometry

Adaptive parts and geometry have underconstrained features, and adjust to design changes.

When you designate underconstrained geometry as adaptive, you specify the geometric elements allowed to change. You control the elements that you want to remain a fixed size or position.

Note: A component cannot be both adaptive and flexible at the same time. You can switch to flexible status to see the same subassembly with its components in multiple positions in an assembly.

Note: Parts created in external CAD systems cannot be made adaptive because imported parts are considered to be fully dimensioned.

Uses for adaptive parts

A part can be useful in multiple assemblies, as long as it can resize as needed. When you create features in a part file, leave some sketch or feature geometry under constrained, and define the features as adaptive . For example, you can drag an extrusion, but leave its depth unspecified.

After you insert a part with underconstrained features into an assembly, designate it as adaptive. When you constrain the part to fixed geometry, its adaptive features resize and change shape.

In an assembly, you can designate a subassembly as adaptive. When parts (and features) in the subassembly are designated as adaptive, features adapt when constrained to geometry outside the subassembly. You can drag under constrained components from within the context of its parent assembly.

You can use an existing part or subassembly to satisfy assembly requirements. Underconstrained features resize when you constrain them to a fixed assembly component. In an assembly file, start by selecting a part or subassembly whose features are set to be adaptive.

Uses for adaptive assembly models

In general, use an adaptive model:

When an assembly design that is not fully defined requires a part or subassembly in a particular position, but you do not know its final size.
When the position or size of a feature depends upon the position or size of a feature on another part in the assembly.

Only one occurrence of a part defines its adaptive features. If you use multiple placements of the same part in an assembly, only one occurrence can be adaptive. However, all occurrences reflect changes to it, including placements in other assemblies.

Geometry that can be adaptive

Undimensioned sketch geometry
Features created from undimensioned sketch geometry
Features with undefined angles or extents
Work features that reference geometry on other parts
Sketches that contain projected origins
Parts that contain adaptive sketches or features
Subassemblies that contain parts with adaptive sketches or features

Models designated as adaptive

For a part or subassembly to adapt when placed in an assembly, it must have one or more adaptive features. To specify adaptive status, use one or more of the following ways:

Specify the adaptive parameters of a part. In the part file or when a part is activated in an assembly file, select the feature in the browser, right-click, and select Properties. In the Feature Properties dialog box, select the sketch, parameters, and From/To termination planes as adaptive.
Make all parameters of the feature adaptive at one time. After you create a feature in a part file, right-click the feature in the browser and select Adaptive.
In the assembly file, select the part or subassembly in the graphics window or the browser, right-click, and select Adaptive. If you do not make a part or subassembly adaptive in an assembly, it is a rigid body. Its size does not change when constrained to other parts, even if you define its features as adaptive in the part file.

Note: When you make a feature adaptive, all occurrences of the feature are also adaptive. If you use the feature in other parts as an iFeature or a pattern, for example, it can resize. To keep a nonadaptive version of a feature, save it with a different file name.

Limitations of adaptive geometry

To ensure that adaptive features and parts update predictably:

Use only one tangency per revolved feature.
Avoid offsets when applying constraints between two points, two lines, or a point and a line.
Avoid a mate constraint between two points, a point and a plane, a point and a line, and a line and a plane.
Avoid tangency between a sphere and a plane, a sphere and a cone, and two spheres.

In assemblies with more than one occurrence of an adaptive part, constraints to nonadaptive occurrences sometimes require two updates to solve correctly.

In a nonadaptive assembly, you can constrain geometry to the origin work features (planes, axes, and origin point). In an adaptive assembly, the same constraints do not affect the position of components.