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Entry  Mon Jan 19 18:27:16 2015, ericq, Update, ASC, QPD ASC saga continues.  oplevPlant.pdfloopDesignComparison.pdfJan16_newLoops_offOn.png
    Reply  Tue Jan 20 02:39:49 2015, ericq, Update, ASC, QPD ASC saga continues.  
    Reply  Tue Feb 10 18:37:17 2015, ericq, Update, ASC, QPD ASC ready to go Feb10_loops_offOn.pngFeb10_newLoops_offOn.xml.zip
       Reply  Tue Feb 24 18:54:26 2015, ericq, Update, ASC, Single arm QPD ASC stability trend.png
Message ID: 10921     Entry time: Tue Jan 20 02:39:49 2015     In reply to: 10920
Author: ericq 
Type: Update 
Category: ASC 
Subject: QPD ASC saga continues.  

Although the QPD loops are less than ideal right now, I made changes to the ASC model to trigger the QPD loops on and off politely, depending on TRX and TRY. The settings are exposed on the ASC screen. However, I have not yet exposed the FM triggering that I also set up to make sure the integrator doesn't misbehave if the arm loses lock. We probably don't want to trigger them on at anything lower than arm powers of about 1.0. 

I've tested the triggering by randomly turning LSC mode on and off, and making sure that the optics don't recieve much of a kick as the QPD loops engage a few seconds after the LSC boosts do, or when lock is lost. This works as long as there isn't much of a DC offset befire the loops are engaged. (Under 20 counts or so is fine)

As a side note, I was going to use the TRIG_SIG signals sent via the LSC model via SHMEM blocks for the ASC triggering, but oddly, the data streams that made it over were actually the MICH and SRCL TRIG_SIGs, instead of XARM and YARM as labelled. I double checked the simulink diagrams; everything seemed fine to me. In any case, ASS was already recieving TRX and TRY directly via RFM, so I just piped those over to the ASC block. This way is probably better anyways, because it directly references the arm powers, instead of the less obvious LSC triggering matrix. 

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