Concave Pocket with Points From CMM

[mach-4]

I have some points from the CMM I want to put a surface on. I started adding curves as shown in the pic. but I will end up with a singularity in the center(there is one point at the center). What's the best way to do this? I can get it to work visually, but not good enough for me to analyze it.

 

[zpaolo]

It depends on what kind of analysis you're going to do, I've done analysis on data points for some years but not using Creo, using instead MathCAD. My suggestion is to ditch the center point completely and do the analyses only on the rings that have more points and no singularity

 

[mach-4]

Basically I need the profile of the surface as best as these few points will give me. The points only deviate by a .0001 or two. I was asked by our PhD if it was possible to give a color representation of the surface to see the high and low spots. Leaving the center point out gave decent results, but note exactly what he was looking for. These would possibly correlate with the heat transfer from a m.o.c.v.d. wafer carrier to the silicon wafer itself due to wafer carrier pocket surface measured locations being closer or farther away from the silicon wafer. Our laser scan has not yielded consistent or accurate results. I do not interact with the laser scanner and do not know what the issue is.

 

[mgnt8]

Build the surface without the center first, then trim back the center gap so it's four sided.
Then build the four sided center surface, which will no longer have the singularity, and merge it with the first surface.
This is the "toupee" method.