To Define a Rigid Body as Ground
1. Open an assembly.
2. Click Assemble. The File Open dialog box opens.
3. Select a component (part or subassembly).
4. Click Open. The Component Placement tab opens.
5. Select Default from the constraint list.
6. Click .
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Because of improved ground body functionality, Mechanism Design models created prior to Pro/ENGINEER 2001 can lose ground body associations for certain components. In this case, you must redefine the component placement.