Measuring principle: Link to actual

[[Ge...]]

Can someone provide a deeper explanation of this measuring principle as it pertains to the attached example.

 

 

 

Link to Actual.pdf

[[Ge...]]

Can admin move this to 3D Inspection & Mesh Editing please?

 

[[Aa...]]

Gerald,

I tried to make a similar construction.  But I'm not sure if I understand fully the issue.  I'm using GOM 2018.

 

Edited June 11, 2025

[[Aa...]]

Using the above, if I were to measure or create actual elements on a perfect sample scan, we would see something like what is shown below.  The measuring principle for the Cone 1 and Plane 1 was "Fitting Element".  The measuring principle for the Intersection Point was "Referenced Construction".  And finally, I used "Link to Actual" as the measuring principle for the Circle --linking the nominal Circle to the actual Intersection Point.  Notice how GOM re-auto labeled the actual intersection point as: "Circle, Intersection Point".

Edited June 11, 2025

[[Aa...]]

Now if I were to check deviation between the nominal location and measured actual location for the Circle, there is a deviation of 10mm, which was the thickness of the square slab.  So even though I'm measuring a perfect scanned sample that exactly matches CAD, I'm still getting a deviation.

On the other hand, if I were to check the deviation between the nominal and measured actual locations for the Intersection Point, I get 0mm of deviation.

[[Aa...]]

To answer your question, I think you probably want to modify your construction slightly before applying the "Link to Actual" measuring principle.  Or maybe use a different strategy depending on what the goal is.