When you use a skeleton model, you set the design and motion intent at the beginning of the design process for a part or subassembly. A skeleton model, placed in the assembly and propagated with it, can be developed independent of the assembly and inserted seamlessly at any time. A skeleton model can be used in more than one assembly.

A skeleton model can be created at any time in the design process. The system always lists and regenerates the newly created skeleton model before all the other components and assembly features.

There are two types of skeleton models: standard skeleton models and motion skeleton models. You create standard skeleton models in an open assembly as parts. Motion skeleton models are subassemblies that contain design skeletons (standard skeletons or internal sketches) and body skeletons. You create standard skeletons using curves, surfaces, and datum features. They can also include solid geometry.

Although skeletons models can only be created in an assembly, you can retrieve, manipulate, and save them as ordinary parts (standard skeleton models) or assemblies (motion skeleton models). Body skeletons are automatically saved as parts when you create them.

Before creating a skeleton model, consider the following points:

Skeleton models do not show up in the BOM unless you specifically include them. They do not contribute to mass or surface properties. They can be displayed in drawing views and can be included during the creation and manipulation of simplified representations and external shrinkwrap features.

Skeleton parts and motion skeletons are placed in the Model Tree before components with solid geometry. Because the functional characteristics of skeletons are different from other components, they are identified in the Model Tree and Mechanism Design Model Tree by the following icons: