Tip: Creating Ground Bodies
Keep the following principles in mind if you are creating a new assembly or adding new components (parts or rigid bodies) to ground:
When creating a new assembly, use the templates so that a default coordinate system and datum planes are automatically defined. The assembly and its features (coordinate system and datum planes) are ground.
Fully constraining a component to the assembly with a default constraint places that component in ground.
A component is considered ground only when it is fully constrained to a component or feature that is already in ground.
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A component can become part of ground when it is only partially constrained if the enable_implied_joints configuration option is set to no.