You can use this method when you have a fixture, but the fiducials are not found in the CAD drawing. In this case, although you have the CAD drawing for the part, you will not be able to establish a proper alignment from the CAD file. You will need to establish the alignment in the Vision tab. Once you do this, you can then use the CAD tab to measure additional features.
To establish an alignment that matches the CAD coordinate system, follow these steps:
Use the method described in the "Live View Alignments" topic to create the alignment features from the Vision tab. Establish an alignment as follows:
You should generally use three surface point features to construct a plane to level to, a line feature to rotate to, and then a point feature for the origin.
For simple 2D parts, however, you should generally use two circle features for leveling, rotating, and setting the origin.
Translate, rotate, and level this alignment to match the CAD coordinates.
Snap the two coordinate systems together in PC-DMIS.
Use the method described in the "CAD View Alignments" topic to create the alignment features (same features as above) from the CAD tab.
Transform the alignment so that it matches the CAD coordinate system. To do this, click the CAD=Part button on the Alignment Utilities dialog box to tell PC-DMIS that the alignment you just created should match up with the CAD coordinate system.