About the Ground relationship

(Home tab→Assemble group→Ground)

The Ground command applies a ground relationship to the selected part in an assembly.

Grounding a part ensures that it remains fixed in the specified position and orientation (relative to the assembly). A grounded part acts as an anchor from which other parts can be positioned. A ground relationship is automatically applied to the first part placed in an assembly.

Parts that have been positioned using assembly relationships relative to a grounded part move relative to the grounded part.

Although an assembly can contain many grounded parts, a set of related parts should be paired with only one grounded part. Depending on the geometry, it may be possible to position a set of related parts to more than one grounded part, but subsequent design changes may cause one or more of the relationships to fail.

When placing a part (dragging it in from the Parts Library) with the Maintain Relationships option cleared, assembly relationships are applied to position and orient a part, but since these relationships are not maintained by the software, a ground relationship is applied (for more information, see Maintain Relationships command (Parts Library Tab)). To access the Maintain Relationship option, right click in the open area of the Parts Library to open the associated options.

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