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Freeform RPS alignement recalculation help


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Hello,

Recently I´ve been struggling with the inspection of a checking fixture specially with the RPS alignment. For this device we have 6 spheres which we use for the RPS alignement as follows: all 6 spheres on X axis to create the plane, 4 alligned spheres on Y axis to create a line for the 2nd plane and 2 spheres (alligned between them but not with the previos 4) for the Z axis and of course since Im not following the 321 rule of RPS alignemnt I have to use the Freeform RPS to match all spheres 2334_cb3727f858f8c8cc4048dc0898429e03.jpg
The result is that all 6 spheres are out of tolerance which invalidates any measure of the device since the RPS alignment is wrong. Because I dont know if the alignment is wrong or the spheres are out of position, I go to "change current base alignment" and replace the nominal coordinates with the actual coordinates obtained from the previous alignment with the expectation of getting 0 deviation and compare the colorimetry of both results to see which one matches better the scanned point cloud to the CAD data. 2334_7fabe0e74e73fdefd2d661f7629a8c25.jpg
2334_185b1aac89193937c87db8769bd6aa4a.jpg
The problem is that after doing this, the deviations are not recalculated so I get the same deviations from previous alignemnt (in the pictures shared I only slightly modified Y and Z coordinates); does this means I cannot update a RPS alignement and I need to start a new measurement plan if I want to change the coordinates to evaluate a different alignment? As a side question, is my original alignment rightor should I stick to 321 RPS and choose only the spheres that are closest to their nominals?

Thanks in advance for any help anyone can provide
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I´ve tried, I get similar results but the problem is that I get too much variance between each alignment test, sometimes as big as >1 mm (with a tolerance of +/- 0.33 mm), so I cannot define a coordinate without getting an out of tolerance flag again in the next run of the program.

I tried the RPS freeform alignment of the spheres with a loop 2334_b2481447f4ad7f413248931ce476dbe9.jpg
I tried RPS freeform alignment of the spheres and then a bestfit (even eliminating everything from the CAD except the spheres and the aluminum plate base to avoid any influence from the other bodies on the bestfit) 2334_ea3614c9a4c982a1008d350351cddbc2.jpg
I tried bestfit alignment with the alumimun plate base elements and then obtaining the position of the spheres 2334_b20164dfffbcb78d1f6d183bcdd3e7e4.jpg
And finally a bestfit alignment with the main body and then obtaining the position of the spheres 2334_fff221808536f215c76a93135f51f987.jpg
This demonstrates that spheres are not within tolerance of their nominal position so I guess my true question is: if I use the coordinates obtained from all my tests (and not the nominal coordinates from the CAD) to get the spheres within tolerance, is it a valid alignment?
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