Dear good people,
I have a 9848-KT (retro-reflector), that has been mounted on a 433 (stage) with two gold mirrors, and is controlled by a CONEX-LTA-HS (motion controller) in an attempt to construct a delay line for a SHG-FROG.
I have downloaded the CONEX-CC drivers and have integrated them into a labview script (attached). I designed a for-loop that steps the stage forward in small increments and saves the position at each step to a text file (to benchmark the motion). Things seem to move reasonably consistently when stepping forward in small increments (~0.005 mm or 5 um). However, when the stage moves forward in increments that we need to move in SHG FROG measurements (~0.0001 - 0.0003 mm) we get a very strange behavior.
Instead of moving forward at each increment of the for-loop the specified length, the stage instead stays at the same position for increasingly larger number of steps before moving again depending on how small the step size was set to. At 0.0001 mm (0.10 um) increments, the stage gets stuck for 5-6 increments of the for-loop, and 0.0003 mm (0.30 um) the stage gets stuck for 3-4 increments, and even at 0.001 mm (1 um) the stage appears to only move every 2 increments of the for loop. Since repeatable unidirectional motion is "guaranteed" at 0.00025 mm (0.25 um) according to the CONEX-LTA-HS specifications, I am starting to wonder if this meets spec, or if it's programming issue on my end. It almost looks like there's rounding going on or something?
I have plots of the motion attached as well.
Has anyone run into this before? Any ideas for troubleshooting?
Thanks for your assistance and patience,
-Deano
