Christian,
I find your images of the noisy and good data interesting: No noise appears when the diameter is less than about 2.8. Is there something about the laser scanner which could affect the noise levels at various diameters?
You said that the signal becomes more and more noisy. How long does this take(time or iterations)? Is the software and all the equipment running continuously during that time? Are you scanning the same part or different parts? Is the part growing hair? Do you see the increase in noise if no part is present to be scanned? Does it happen if the scanner is turned off?
Sequence structures and local variables often lead to poorly performing LabVIEW code because LV is a dataflow language and these elements violate dataflow. Search the Forum for numerous posts on those topics and alternatives. They may be causing some problems, but probably have nothing to do with your noise.
In Case 2 the Initiate Motion Change loop will always stop after one iteration, so why have a loop?
Lynn
