To Export to Motion Envelope
1. In an open assembly, click > 
Save As > Save a Copy. The Save a Copy dialog box opens.
Save As > Save a Copy. The Save a Copy dialog box opens.2. Select Motion Envlp in the Type box.
3. Accept the default name in the New file name box or type a new model name for the export.
4. Click OK. The Create Motion Envelope dialog box and the Open dialog box open. In the Open dialog box, Frames File (*.fra) appears in the Type box.
5. Select the Frames file you want to open from the list of available files or browse to find the Frames file. The Open dialog box closes.
 | Frames files are created in the Mechanical Design application. |
6. Complete the Create Motion Envelope dialog box and click OK.