Review - PR 258974 FCF Parallelism returns value 0

huangyhg

<< Frank Herr  --  01/08/09  17:14:31>>
If we construct a plane in the sample hits of an AutoFeature circle and calculate the parallelism against a second measured plane we get a value with legacy dimension parallelism. With feature control frame the value is 0.

Steps to reproduce:
See attached part program.
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<< Don Turcotte  --  01/14/09  10:04:45>>
If you construct a plane from a scan, you can do a parallelism of this constructed plane since PC-DMIS has the points from the scan.   This would also work with a plane constructed from individual point features (for example, autovector points or autosurface points).  This just does not work with the sample points from an autocircle.  This would be an enhancement to PC-DMIS.
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<< Changes made by Don Turcotte -- 01/14/09  10:05:30>>
Action:  Don Turcotte to David Petrizze, Status:  OPEN to REVIEW
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<< Changes made by Don Turcotte -- 01/14/09  08:12:57>>
Action:  Frank Herr to Don Turcotte
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<< Frank Herr  --  01/14/09  11:48:47>>
Don, thanks for your description. It's not nice that the sample hits are not longer available if I construct a feature. How it is handled if I construct a plane in a scan? Is it possible to use this constructed plane for a parallelism calculation? If yes, why it is different against the construction in my case?
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<< Changes made by Frank Herr -- 01/14/09  11:48:52>>
Status:  RESOLVED to OPEN
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<< Don Turcotte  --  01/13/09  14:33:24>>
PC-DMIS calculates parallelism of a plane using the probe hit points of the considered plane compared to a datum plane.  Since a constructed plane has no hit points, you must use the constructed plane as the datum to get a non-zero value.
Your legacy dimension defines the parallelism of EBENE1 to EBENE2.  In legacy dimensions, the second feature acts as the datum, so in this case the constructed plane EBENE2 is the datum and you get a non-zero value.  If you defined a legacy parallelism of EBENE2 to EBENE1, you would get zero.
Your FCF parallelism has defined EBENE1 as the datum.  Since EBENE2 is the constructed plane and has no hit points, the reported parallelism is zero.  If you define EBENE2 as the datum and create an FCF parallelism of EBENE1 to the datum, then you will get the same non-zero value that is reported by your legacy dimension.
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<< Changes made by Don Turcotte -- 01/13/09  14:33:50>>
Action:  Don Turcotte to Frank Herr, Status:  OPEN to RESOLVED
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<< Changes made by Tim Wernicke -- 01/08/09  11:24:19>>
Priority:  to Critical
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